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Neurons in the nucleus raphe interpositus have tonic activity that suppresses saccadic burst neurons (BNs) during eye fixations, and that is inhibited before and during saccades in all directions (omnipause neurons, OPNs). We have previously demonstrated via intracellular recording and anatomical staining in anesthetized cats of both sexes that OPNs are inhibited by BNs in the medullary reticular formation (horizontal inhibitory BNs, IBNs). These horizontal IBNs receive monosynaptic input from the caudal horizontal saccade area of the superior colliculus (SC), and then produce monosynaptic inhibition in OPNs, providing a mechanism to trigger saccades. However, it is well known that the neural circuits driving horizontal components of saccades are independent from the circuits driving vertical components. Thus, our previous results are unable to explain how purely vertical saccades are triggered. Here, we again apply intracellular recording to show that a disynaptic vertical IBN circuit exists, analogous to the horizontal circuit. Specifically, we show that stimulation of the SC rostral vertical saccade area produces disynaptic inhibition in OPNs, which is not abolished by midline section between the horizontal IBNs. This excludes the possibility that horizontal IBNs could be responsible for the OPN inhibition during vertical saccades. We then show that vertical IBNs in the interstitial nucleus of Cajal, which receive monosynaptic input from rostral SC, are responsible for the disynaptic inhibition of OPNs. These results indicate that a similarly functioning SC-IBN-OPN circuit exists for both the horizontal and vertical oculomotor pathways. These two IBN-mediated circuits are capable of triggering saccades in any direction. [ABSTRACT FROM AUTHOR]

Summary There is a histopathological similarity between cutaneous apocrine carcinoma (CAC) and breast carcinoma. Cutaneous histiocytoid or signet-ring cell (SRC) carcinoma is a rare neoplasm, which usually occurs on the eyelid, and less commonly on the axilla. The precise histogenesis of this carcinoma remains controversial. We report the case of a man with a cutaneous histiocytoid SRC carcinoma of the axilla having histopathological and immunohistochemical features that were quite similar to histiocytoid lobular carcinoma (histiocytoid LC) of the breast, which is a subtype of classic invasive lobular carcinoma of the breast with apocrine differentiation. We consider this case to be a type of CAC equivalent to histiocytoid LC of the breast, based on the features and the occurrence on the axilla. The patient was treated with adjuvant chemotherapy according to the general guidelines for the treatment of breast carcinoma. [ABSTRACT FROM AUTHOR]

Abstract: The effect of chemical composition of Y2O3–Al2O3–SiO2-based intergranular glass on superplastic deformation of β-Si3N4 was studied by compression tests at 1873K. All hot isostatically pressed Si3N4 materials had essentially the same microstructure and the same amount of glass phase, which was different in composition only. The relation between flow stress and glass composition qualitatively corresponded to the effect of chemical composition on viscosity of Y2O3–Al2O3–SiO2 glass. However, the flow stress was not proportional to the viscosity of Y2O3–Al2O3–SiO2 glass, probably because the composition of intergranular glass phase had changed by dissolving Si3N4. The strain hardening (increase of flow stress with deformation) was dependent on the chemical composition of intergranular glass. Actually, the apparent strain hardening was not proportional to the strain but was proportional to time. The crystallization of Si2N2O was also proportional to time, and was dependent on the chemical composition of the intergranular glass in a similar way to the strain hardening. Thus, it was suggested that the crystallization of Si2N2O reduced the amount of the intergranular glass, thereby increasing flow stress. [Copyright &y& Elsevier]

Abstract: The sintering stress is originally defined for equilibrium states, where the mechanical stress just balances the internal surface tension forces so that the porous material does not shrink. The sintering stress for a given porous structure in equilibrium was calculated by three methods theoretically; the energy difference method, the curvature method, and the force balance method. The sintering stresses by three different methods were exactly the same for idealized porous materials in equilibrium, in which the pore surface had a constant curvature at any point. The grain boundary energy contributed to the sintering stress, and it affected the thermal stability of the porous structure. [Copyright &y& Elsevier]

The maintenance of the equiaxed shape of grains after a large deformation is a common feature of superplasticity in polycrystalline solids. This feature is similar to that seen in the deformation of soap froth. The topological transformation of the grains was analyzed by using the Surface Evolver which simulated the three-dimensional simple shearing flow of soap froth. In this model the equiaxed shape of the grains could be maintained in a disordered system of N grains when both face-creation switching and face-elimination switching occurred αγN times in shear strain γ. The simulation gave α-values from 4.9 to 4.5 in the monodispersed structure and α=4.7 in the polydispersed structure. The strain, which is associated with grain switching, is represented by γ″=ΔF/αN, where ΔF is the mean cumulative number of grain switchings. The intragranular strain, which is related to the aspect ratio of the grains, is represented by γ′=γ−γ″. The back stress by boundary tension was proportional to γ′. It can act to restore the equiaxed shape, and is one of the origins of anelasticity. [Copyright &y& Elsevier]

Three-dimensional grain growth was analysed using the Surface Evolver program that simulates grain-boundary motion by curvature. When the grainboundary network reached a statistically self-similar steady state structure in the norm al grain growth period, the mean life span until the disappearance of grains could be predicted from the distribution function of the norm alized grain size and the distribution function of the num ber of faces in normal grain growth period. [ABSTRACT FROM AUTHOR]

A nonspherical glass particle relaxes to its equilibrium shape by viscous flow driven by capillarity at elevated temperatures. The virial method is applied to Stokes equation for studying the viscous sintering of an ellipsoidal particle. The spheroidization, or the retraction of the particle, is a result of anisotropic deformation driven by the deviatoric components of the sintering stress, which arises from the surface energy tensor. The present simulation of spheroidization is in good agreement with the prediction by the three-dimensional finite element method. Jackson and Tucker's model on deformation of a liquid droplet can be also understood as a response to the sintering stress. [ABSTRACT FROM AUTHOR]

Introduction/Background It is important to assess the fracture risk associated with metastasis in the proximal femur. The study aimed to assess the effect of tumor location on the risk of pathological fracture of the proximal femur and investigate the fracture risk not only in the stance-loading configuration (SC), but also in the fall-loading configuration (FC) using a computed tomography (CT)-based finite element (FE) method based on a simulated metastatic model. Material and method The axial CT scans of the proximal femora of healthy men ( n = 4; age range, 42–48 years) and post-menopausal women ( n = 4; age range, 69–78 years) were obtained with a calibration phantom, from which the three-dimensional FE models were constructed. A single 15-mm-diameter spherical void simulating a tumor was created at various locations from the neck to subtrochanter level. Nonlinear FE analyses were performed. Results The mean predicted fracture loads without spherical voids in the SC were 7700 N in men and 4370 N in women. With the void at the medial femoral neck and in the region anteromedial to lesser trochanter, the mean predicted load significantly reduced to 51.3% and 59.4% in men and 34.1% and 64.5% in women, respectively. The mean predicted fracture loads without a spherical void in the FC were 2500 N in men and 1862 N in women. With the void at the medial and posterior femoral neck, the predicted fracture load was significantly reduced to 65.7% and 79.7% in men and 48.3% and 65.4% in women, respectively. Conclusion These results showed that the risk of pathologic fracture was quite high in both the SC and FC when the lytic lesion existed along the principal compressive trabecular trajectory or posterior neck. Prophylactic intervention should be considered for metastases at these locations. [ABSTRACT FROM AUTHOR]

Introduction/Background Congenital insensitivity to pain with anhidrosis (CIPA), also called hereditary sensory and autonomic neuropathy type IV, is an autosomal recessive disorder manifesting in a generalized loss of pain and thermal sensation, a lack of sweating, and is associated with variable degrees of intellectual disability and/or learning deficits. In patients with CIPA, musculoskeletal complications are frequent including repeated fractures and joint dislocations, avascular bone necrosis, and Charcot arthropathy, mainly in the lower extremities. Though complications in hip and knee joints may eventually lead to difficulty in ambulation, prevention and management of hip/knee pathologies are difficult and scarcely reported so far. Material and method We retrospectively reviewed the medical records of 19 patients (ten males and nine females) who visited our department since 2006. The age at final visit ranged from four to 64 years (mean 20). Results Hip pathologies were identified in 14 joints in eight patients, excluding mild acetabular dysplasia. Six joints in three patients had already been destroyed at initial visit. Two joints in a patient developed fixed dislocations without any treatment. Orthoses were prescribed in four patients (six joints), three hip-action braces and one HKAFO, and three patients obtained relatively good results. Knee pathologies existed in seven joints in seven patients, excluding mild joint instability or genu varum. Two joints had already been destroyed at initial visit. One joint developed a severe Charcot joint without any treatment. KAFO was prescribed for four joints, but they all led to Charcot joints and three of them underwent surgery. Conclusion Hip and knee pathologies are frequent in CIPA and difficult to manage. Orthotic treatment for hip pathologies may be beneficial for maintaining reduction. On the contrary, KAFO can hardly prevent developing Charcot knee joints. [ABSTRACT FROM AUTHOR]

We report a 64-year-old Japanese woman with a history of progressive loss of motor function and painful swelling of large joints. At the age of 54, profound calcification appeared around the shoulder and hip joints, which did not heal after repeated surgical resections. Iliac bone biopsy revealed osteomalacic changes. Laboratory data showed low serum alkaline phosphatase (ALP) activity and a high urine phosphoethanolamine (PEA) concentration with normal serum calcium, phosphate, and fibroblast growth factor 23 (FGF23) levels. Subsequent genetic analysis of the ALPL gene confirmed the diagnosis of hypophosphatasia (HPP) with the identification of a heterozygous single nucleotide deletion, c.1559delT (p.Leu520ArgfsX86). We started a mineral-targeted enzyme replacement therapy, asfotase alfa (AA), to treat the patient's musculoskeletal symptoms. A follow-up bone biopsy after 12 months of AA treatment showed improvement of osteomalacia. Calcified deposits around the large joints were unchanged radiographically. To our knowledge, this is the first report of a patient with an adult-onset HPP who presented with profound calcification around multiple joints. Nonspecific clinical signs and symptoms in patients with adult-onset HPP often result in delayed diagnosis or misdiagnosis. We propose that bone biopsy and genetic analysis should be considered along with laboratory analysis for all patients with ectopic calcification around joints of unknown etiology for accurate diagnosis and better treatment. [ABSTRACT FROM AUTHOR]

Neurons in the interstitial nucleus of Cajal (INC) that are known to be involved in eye and head movements are excitatory. We investigated the input-output organization of inhibitory INC neurons involved in controlling vertical saccades. Intracellular recordings were made in INC neurons activated antidromically by stimulation of the contralateral trochlear or oculomotor nucleus, and their synaptic input properties from the superior colliculi (SCs) and the contralateral INC were analyzed in anesthetized cats. Many INC neurons projected to the contralateral trochlear nucleus, Forel's field H, INC, and oculomotor nucleus, and mainly received monosynaptic excitation followed by disynaptic inhibition from the ipsi- and contralateral SCs. After sectioning the commissural connections between the SCs, these neurons received monosynaptic excitation from the ipsilateral medial SC and disynaptic inhibition via the INC from the contralateral lateral SC. Another group of INC neurons were antidromically activated from the contralateral oculomotor nucleus, INC and Forel's field H, but not from the trochlear nucleus, and received monosynaptic excitation from the ipsilateral lateral SC and disynaptic inhibition from the contralateral medial SC. The former group was considered to inhibit contralateral trochlear and inferior rectus motoneurons in upward saccades, whereas the latter was considered to inhibit contralateral superior rectus and inferior oblique motoneurons in downward saccades. The mutual inhibition existed between these two groups of INC neurons for upward saccades on one side and downward saccades on the other. This pattern of input-output organization of inhibitory INC neurons suggests that the basic neural circuits for horizontal and vertical saccades are similar. [ABSTRACT FROM AUTHOR]

Abstract: A thermal barrier coating (TBC) made of porous ZrO2 ceramic was formed on a nickel-based single crystal superalloy (NSA) by plasma electrolytic oxidation (PEO). An oxidation barrier coating (OBC) made of Al2O3 based ceramics was created between the TBC and NSA substrate by coating the NSA with aluminum before the PEO treatment that oxidized it into Al2O3. The key finding of this study is that ZrO2-based TBC can be formed by PEO of an OBC-coated NSA in a K2[Zr(CO3)2(OH)2] solution. The TBC contained monoclinic-, tetragonal- and cubic-ZrO2 crystals and had a unique gradient porous texture. Relatively large pores existed near the interface between OBC and TBC, and the number and size of pores in the TBC decreased with increasing distance from the interface. The TBC had ZrO2 grains with a diameter of about 300nm. The TBC shows a low thermal conductivity equivalent to that of conventional TBCs owing to this porous texture with fine grains. The bond strength between the PEO coating and substrate was 26.8±6.6MPa, which is close to that of conventional TBCs. [Copyright &y& Elsevier]

A letter to the editor is presented which discusses the matrix-producing apocrine carcinoma of the skin in an 84-year-old woman who presented with an erythematous, firm nodule on upper left arm with an irregular surface.

Abstract: The shrinkage of a closed pore in the sintering of a particle cluster was analyzed. The shrinkage rate was proportional to the sintering stress, and inversely proportional to the macroscopic viscosity. The sintering stress was determined as a function of the pore volume, the dihedral angle, and the pore coordination number. The macroscopic viscosity was expressed as a function of pore volume in sintering by viscous flow, lattice diffusion, interface-controlled lattice diffusion, or grain boundary diffusion. The pore shrinkage was simulated using the Surface Evolver program in three dimensions. As the large pore shrank, the pore coordination number decreased gradually. This topological transformation of the pore increased the sintering stress and promoted densification. [Copyright &y& Elsevier]

Abstract: Coarsening during sintering results from surface motion, while grain growth results from grain boundary motion. The sintering of two spherical particles of different sizes, and subsequent coarsening and grain growth, were studied until the smaller particle disappeared. When the grain boundary mobility Mgb was comparable to the surface mobility Ms, the curved grain boundary migrated out of the smaller particle in a shorter time with increasing ratio of grain boundary energy γgb to surface energy γs. As long as the grain boundary was anchored to the surface triple junction, the grain boundary was approximated to be flat at the limit of Mgb≫Ms. The motion of flat grain boundary was affected by γgb/γs in a different way to that of the curved grain boundary. [Copyright &y& Elsevier]

Cell surface glycoconjugates are thought to mediate cell–cell recognition and to play roles in neuronal development and functions. We demonstrated here that exposure of neuronal cells to nanomolar levels of glyco-chains with an N-acetylgalactosamine (GalNAc) residue at the non-reducing termini (GalNAc-S) such as GalNAcβ4(Neu5Acα3)Galβ4GlcCer (GM2) ganglioside, its oligosaccharide portion, GalNAcβ4Galβ4GlcCer (Gg3) Cer, GalNAcα3GalNAcβ3Galα4Galβ4GlcCer (Gb5) Cer (Forssman hapten) and α1–4 linked oligomers of GalNAc, induced a rapid and transient activation of cAMP-dependent protein kinase (PKA) in subplasmalemma. The treatment was accompanied by peripheral actin polymerization and filopodia formation in NG108–15 cells and primary cultured hippocampal neurons, but not in glial cells. A cAMP-dependent protein kinase (PKA) selective inhibitor and an adenylate cyclase inhibitor blocked both PKA activation and the subsequent filopodia formation. A small GTPase cdc42 was a potential downstream target of GalNAc-S-activated PKA. These results suggest that extracellular GalNAc-S serve as potential regulators of the filopodia formation in neuronal cells by triggering the activation of PKA followed by cdc42 up-regulation via a cell surface receptor-like component. Filopodia formation induced by GalNAc-S may have a physiological relevance because long-term exposure to GalNAc-S enhanced F-actin-rich dendrite generation of primary cultured hippocampal neurons, and PKA-dependent dendritic outgrowth and branch formation of primary cultured cerebellar Purkinje neurons, in which actin isoforms were localized to motile structures in dendrites. These findings provide evidence for a novel GalNAc/PKA-signaling cascade in regulating some neuronal maturation. [Copyright &y& Elsevier]

Abstract: Plasma electrolytic oxidation (PEO) was used to make a multifunctional porous titanium oxide (TiO2) coating on a titanium substrate. The key finding of this study is that a highly crystalline TiO2 coating can be made by performing the PEO in an ammonium acetate (CH3COONH4) solution; the PEO coating was formed by alternating between rapid heating by spark discharges and quenching in the solution. The high crystallinity of the TiO2 led to the surface having multiple functions, including apatite forming ability and photocatalytic activity. Hydroxyapatite formed on the PEO coating when it was soaked in simulated body fluid. The good apatite forming ability can be attributed to the high density of hydroxyl groups on the anatase and rutile phases in the coating. The degradation of methylene blue under ultraviolet radiation indicated that the coating had high photocatalytic activity. [Copyright &y& Elsevier]

Abstract: A method to analyze the mechanics of sintering of a single grain boundary was developed by using specimens fabricated by focused ion beam micro-machining. The translational motion and rotation of particles in sintering are influenced by the grain boundary diffusion coefficient and grain boundary energy; both are dependent on crystallographic orientation. Three-dimensional computer simulation was used to analyze the shrinkage and rotation as a response to sintering force and torque, respectively. The model experiments on gold were compared with the simulation results to determine the depth of the cusps on the plot of grain boundary energy vs. misorientation angle, the grain boundary diffusion coefficients, and the surface diffusion coefficient. [Copyright &y& Elsevier]

In the hydrate crystal of 1:1 salt with 1,3-diazine and chloranilic acid (Hca), (1,3-diazineH)·HO·Hca, an unique hydrogen-bonded molecular aggregate is formed. There exists proton disorder in the N-H...O hydrogen bond between 1,3-diazinium ion and water (HO) of crystallization. In order to reveal dynamic aspect of this disorder, Cl NQR measurements were conducted. Two resonance lines observed at 35.973 and 35.449 MHz at 321 K split into four lines below T = 198 K clearly showing occurrence of a solid-solid phase transition; 36.565, 36.357, 36.011, 35.974 MHz at 77 K. Temperature dependence of spin-lattice relaxation time T in high-temperature phase was observed to obey an Arrhenius-type relation with the activation energy of 8.5 kJ mol. This result leads to the conclusion that proton exchange in the N-H...O hydrogen bond takes place in the high-temperature phase. Specific heat measurements by DSC resulted in the transition entropy ΔS = 1.3 J K per 1 mole [(1,3-diazineH)·HO·Hca] which is far less than 2 R ln2 = 11.5 J K mol. It is expected that proton exchange in the two hydrogen bonds within the aggregate does not occur independently but concertedly with strong correlation in the high-temperature phase. [ABSTRACT FROM AUTHOR]

Previous electrophysiological studies have shown that the commissural connections between the two superior colliculi are mainly inhibitory with fewer excitatory connections. However, the functional roles of the commissural connections are not well understood, so we sought to clarify the physiology of tectal commissural excitation and inhibition of tectoreticular neurons (TRNs) in the “fixation ” and “saccade ” zones of the superior colliculus (SC). By recording intracellular potentials, we identified TRNs by their antidromic responses to stimulation of the omnipause neuron (OPN) and inhibitory burst neuron (IBN) regions and analyzed the effects of stimulation of the contralateral SC on these TRNs in anesthetized cats. TRNs in the caudal SC (saccade neurons) projected to the IBN region, and received mono- or disynaptic inhibition from the entire rostrocaudal extent of the contralateral SC. In contrast, TRNs in the rostral SC projected to the OPN or IBN region and received monosynaptic excitation from the most rostral level of the contralateral SC, and mono- or disynaptic inhibition from its entire rostrocaudal extent. Among the rostral TRNs with commissural excitation, IBN-projecting TRNs also projected to Forel's field H (vertical gaze center), suggesting that they were most likely saccade neurons related to vertical saccades. In contrast, TRNs projecting only to the OPN region were most likely fixation neurons. Most putative inhibitory neurons in the rostral SC had multiple axon branches throughout the rostrocaudal extent of the contralateral SC, whereas excitatory commissural neurons, most of which were rostral TRNs, distributed terminals to a discrete region in the rostral SC. [ABSTRACT FROM AUTHOR]

The caudal superior colliculus (SC) contains movement neurons that fire during saccades and the rostral SC contains fixation neurons that fire during visual fixation, suggesting potentially different functions for these 2 regions. To study whether these areas might have different projections, we characterized synaptic inputs from the rostral and caudal SC to inhibitory burst neurons (IBNs) in anesthetized cats. We recorded intracellular potentials from neurons in the IBN region and identified them as IBNs based on their antidromic activation from the contralateral abducens nucleus and short-latency excitation from the contralateral caudal SC and/or single-cell morphology. IBNs received disynaptic inhibition from the ipsilateral caudal SC and disynaptic inhibition from the rostral SC on both sides. Stimulation of the contralateral IBN region evoked monosynaptic inhibition in IBNs, which was enhanced by preconditioning stimulation of the ipsilateral caudal SC. A midline section between the IBN regions eliminated inhibition from the ipsilateral caudal SC, but inhibition from the rostral SC remained unaffected, indicating that the latter inhibition was mediated by inhibitory interneurons other than IBNs. A transverse section of the brain stem rostral to the pause neuron (PN) region eliminated inhibition from the rostral SC, suggesting that this inhibition is mediated by PNs. These results indicate that the most rostral SC inhibits bilateral IBNs, most likely via PNs, and the more caudal SC exerts monosynaptic excitation on contralateral IBNs and antagonistic inhibition on ipsilateral IBNs via contralateral IBNs. The most rostral SC may play roles in maintaining fixation by inhibition of burst neurons and facilitating saccadic initiation by releasing their inhibition. [ABSTRACT FROM AUTHOR]

Vestibular inputs to the cerebral cortex are important for spatial orientation, body equilibrium, and head and eye movements. We examined vestibular input to the periarcuate cortex in the Japanese monkey by analyzing laminar field potentials evoked by electrical stimulation of the vestibular nerve. Laminar field potential analysis in the depths of the cerebral cortex showed that vestibular-evoked potentials consisted of early-positive and late-negative potentials and early-negative and late-positive potentials in the superficial and deep layers of the periarcuate cortex, respectively, with latencies of 4.8–6.3 ms, suggesting that these potentials were directly conveyed to the cortex through the thalamus. These potentials were distributed continuously in the fundus, dorsal and ventral banks of the spur and the bottom of the junctional part of the arcuate sulcus and spur. This vestibular-projecting area overlapped the cortical distribution of corticovestibular neurons that were retrogradely labeled by tracer injection into the vestibular nuclei (previously reported area 6pa), and also the distribution of smooth pursuit-related neurons recorded in the periarcuate cortex including area 8 in a trained monkey. These results are discussed in relation to the function of vestibular information in control of smooth pursuit and efferents of the smooth pursuit-related frontal eye field. [Copyright &y& Elsevier]