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The cortex processes information through intricate circuitry and outputs to multiple brain areas by different sets of pyramidal cells (PCs). PCs form intra- and inter-laminar subnetworks, depending on PC projection subtypes. However, it remains unknown how individual PC subtypes are involved in cortical network activity and, thereby, in distinct brain functions. Here, we examined the effects of optogenetic manipulations of specific PC subtypes on network activity in the motor cortex. In layer V, the beta/gamma frequency band of oscillation was evoked by photostimulation, depending on PC subtypes. Our experimental and simulation results suggest that oscillatory activity is generated in reciprocal connections between pyramidal tract (PT) and fast-spiking cells. A similar frequency band was also observed in local field potentials during a pattern learning task. Manipulation of PT cell activity affected beta/gamma band power and learning. Our results suggest that PT cell-dependent oscillations play important roles in motor learning., Otsuka and Kawaguchi investigate how manipulation of pyramidal cell subtypes in the motor cortex affects cortical network activity. Their findings suggest that pyramidal cell type cell-dependent oscillatory activity play an important role in motor learning.

Summary Precise regulation of neuronal migration termination is crucial for the establishment of brain cytoarchitectures. However, little is known about how neurons terminate migration. Here we focused on interactions between migrating cortical neurons and their substrates, radial glial (RG) cells, and analyzed the role of Plexin A2 and A4 (PlxnA2/A4) receptors and their repulsive ligand, Semaphorin 6A (Sema6A), for this process. In both PlxnA2/A4 double-knockout and Sema6A mutant mice, the outermost cortical plate neurons ectopically invade layer 1 at a stage when they should reach their destinations. PlxnA2/A4 proteins are abundantly expressed on their leading processes, whereas Sema6A mRNA is enriched in RG cell somata. Cell-targeted gene expression and conditional knockouts indicate critical roles for these molecules. We hypothesize that the timely appearance of repulsive signaling mediated by Sema6A–PlxnA2/A4 weakens migrating neuron–RG cell interactions, leading to migration termination., Graphical Abstract, Highlights • Loss of PlxnA2/A4 results in superficial layer neurons invading layer 1 • PlxnA2/A4 works cell autonomously to settle these neurons properly • Lack of Sema6A in radial glial cells causes similar mispositioning of these neurons • Sema6A–PlxnA2/A4 signaling determines settling position of superficial layer neurons, Biological Sciences; Molecular Biology; Neuroscience; Molecular Neuroscience; Cellular Neuroscience

The cortex contains multiple neuron types with specific connectivity and functions. Recent progress has provided a better understanding of the interactions of these neuron types as well as their output organization particularly for the frontal cortex, with implications for the circuit mechanisms underlying cortical oscillations that have cognitive functions. Layer 5 pyramidal cells (PCs) in the frontal cortex comprise two major subtypes: crossed-corticostriatal (CCS) and corticopontine (CPn) cells. Functionally, CCS and CPn cells exhibit similar phase-dependent firing during gamma waves but participate in two distinct subnetworks that are linked unidirectionally from CCS to CPn cells. GABAergic parvalbumin-expressing fast-spiking (PV-FS) cells, necessary for gamma oscillation, innervate PCs, with stronger and global inhibition to somata and weaker and localized inhibitions to dendritic shafts/spines. While PV-FS cells form reciprocal connections with both CCS and CPn cells, the excitation from CPn to PV-FS cells exhibits short-term synaptic dynamics conducive for oscillation induction. The electrical coupling between PV-FS cells facilitates spike synchronization among PV-FS cells receiving common excitatory inputs from local PCs and inhibits other PV-FS cells via electrically communicated spike afterhyperpolarizations. These connectivity characteristics can promote synchronous firing in the local networks of CPn cells and firing of some CCS cells by anode-break excitation. Thus subsets of L5 CCS and CPn cells within different levels of connection hierarchy exhibit coordinated activity via their common connections with PV-FS cells, and the resulting PC output drives diverse neuronal targets in cortical layer 1 and the striatum with specific temporal precision, expanding the computational power of the cortical network.

There exist two major types of striatum-targeting neocortical neurons, specifically, intratelencephalic (IT) neurons and pyramidal-tract (PT) neurons. Regarding their striatal projections, it was once suggested that IT axons are extended whereas PT axons are primarily focal. However, subsequent study with an increased number of well-stained extended axons concluded that such an apparent distinction was spurious due to limited sample size. Recent work using genetically labeled neurons reintroduced the differential spatial extent of the striatal projections of IT and PT neurons through population-level analyses, complemented by observations of single axons. However, quantitative analysis of a large number of axons remained to be conducted. We analyzed the data of axonal end-points of 161 IT neurons and 33 PT neurons in the MouseLight database (http://ml-neuronbrowser.janelia.org/). The number of axonal end-points in the ipsilateral striatum exhibits roughly monotonically decreasing distributions in both neuron types. However, the proportion of neurons having >50 ipsilateral end-points is larger in IT neurons than in PT neurons. Moreover, distinguishing IT subpopulations in the secondary motor area (MOs), layer 5 neurons and bilateral striatum-targeting layer 2/3 neurons, but not contralateral striatum-non-targeting layer 2/3 neurons, have a larger number of ipsilateral end-points than MOs PT neurons. We also found that IT ipsilateral striatal axonal end-points are on average more widely distributed than PT end-points, especially in the medial-lateral direction. These results indicate that IT and PT striatal axons differ in the frequency of having numerous end-points and the spatial extent of end-points while there are wide varieties within each neuron type.

Highlights • An enterolith occurring in the duodenal afferent loop after distal gastrectomy, leading to obstructive jaundice and ileus is rare. • Although afferent loop enterolith formation is uncommon, it should be considered when a patient with a history of B-II gastrectomy or Roux-en-Y reconstruction presents with fever, abdominal pain, or other symptoms suggesting acute cholangitis. • Surgical treatment should be considered for afferent loop obstruction or intestinal obstruction that is refractory to conservative treatment., Introduction Afferent loop obstruction is an uncommon complication associated with Billroth II reconstruction or Roux-en-Y reconstruction after gastrectomy. Moreover, cases where the obstruction is caused by enterolith are rare. Here, we report a rare case of afferent loop obstruction caused by an enterolith after Roux-en-Y reconstruction of gastrectomy; subsequently, leading to ileus in the ileum. Presentation of case An 84-year-old man who received a Roux-en-Y distal gastrectomy for gastric cancer presented with symptoms of fever and jaundice 14 months later. Computed tomography (CT) scan revealed an enterolith in the duodenal afferent loop and a dilated intrahepatic bile duct. Although the obstructive jaundice and fever disappeared with conservative therapy, ileus occurred due to the movement of the enterolith into the ileum, which was refractory to conservative therapy. Therefore, enterotomy was performed to remove the enterolith, and the patient had an uneventful recovery. Histologically, the enterolith derived from food residue. No postsurgical sign of recurrence has been noted for 6 months. Conclusion We report a rare case where an enterolith in a duodenal afferent loop after distal gastrectomy led to obstructive jaundice, and subsequently, caused ileus by its movement into the ileum.

Highlights • Appendicitis with liver abscess and sessile serrated adenoma/polyp is rare. • Ileocecal resection was performed for an inflammatory mass in the ileocecum. • The patient was successfully treated with a combination of surgery and antibiotics., Introduction Although appendicitis is a common disease, appendicitis concurrent with liver abscesses and sessile serrated adenoma/polyp (SSA/P) is rare. Presentation of case A 69-year-old man presented with symptoms of abdominal pain and fever. Computed tomography (CT) revealed multiple liver abscesses and an enlarged appendix with a pseudotumoral appearance, which suggested acute appendicitis. In the emergency operation, ileocecal resection was performed for the perforated appendicitis with an inflammatory mass in the ileocecum. On macroscopic examination, the torose lesion was localized at next to the appendiceal orifice. The tumor was diagnosed as SSA/P based on the microscopic finding. The postoperative course was uneventful, and the liver abscesses were cured by antibiotic therapy. The patient was discharged 17 days after the surgery. Discussion In this case, SSA/P localization at next to the appendiceal orifice was suggested as the cause of the perforated appendicitis with multiple liver abscesses. The patient was successfully treated with a combination of surgery and antibiotic therapy. Conclusion This is the first reported case of a patient with SSA/P that led to acute appendicitis with multiple pyogenic liver abscesses.

A prominent feature of neocortical pyramidal cells (PCs) is their numerous projections to diverse brain areas. In layer 5 (L5) of the rat frontal cortex, there are 2 major subtypes of PCs that differ in their long-range axonal projections, corticopontine (CPn) cells and crossed corticostriatal (CCS) cells. The outputs of these L5 PCs can be regulated by feedback inhibition from neighboring cortical GABAergic cells. Two major subtypes of GABAergic cells are parvalbumin (PV)-positive and somatostatin (SOM)-positive cells. PV cells have a fast-spiking (FS) firing pattern, while SOM cells have a low threshold spike (LTS) and regular spiking. In this study, we found that the 2 PC subtypes in L5 selectively make recurrent connections with LTS cells. The connection patterns correlated with the morphological and physiological diversity of LTS cells. LTS cells with high input resistance (Ri) exhibited more compact dendrites and more rebound spikes than LTS cells with low Ri, which had vertically elongated dendrites. LTS subgroups differently inhibited the PC subtypes, although FS cells made nonselective connections with both projection subtypes. These results demonstrate a novel recurrent network of inhibitory and projection-specific excitatory neurons within the neocortex.

The frontal cortical areas make a coordinated response that generates appropriate behavior commands, using individual local circuits with corticostriatal and corticocortical connections in longer time scales than sensory areas. In secondary motor cortex (M2), situated between the prefrontal and primary motor areas, major subtypes of layer 5 corticostriatal cells are crossed-corticostriatal (CCS) cells innervating both sides of striatum, and corticopontine (CPn) cells projecting to the ipsilateral striatum and pontine nuclei. CCS cells innervate CPn cells unidirectionally: the former are therefore hierarchically higher than the latter among L5 corticostriatal cells. CCS cells project directly to both frontal and nonfrontal areas. On the other hand, CPn cells innervate the thalamus and layer 1a of frontal areas, where thalamic fibers relaying basal ganglia outputs are distributed. Thus, CCS cells can make activities of frontal areas in concert with those of nonfrontal area using corticocortical loops, whereas CPn cells are more involved in closed corticostriatal loops than CCS cells. Since reciprocal connections between CPn cells with facilitatory synapses may be related to persistent activity, CPn cells play a key role of longer time constant processes in corticostriatal as well as in corticocortical loops between the frontal areas.

Highlights • De Garengeot hernia with a groin subcutaneous abscess is rare. • Appendectomy and herniorrhaphy via the same incision may be more effective. • Clinicians should consider de Garengeot hernia in patients with a groin hernia., Introduction De Garengeot hernia is rare. Although previous reports have suggested various surgical options according to patient condition, comorbidities, surgeon preference, and clinical findings during surgery, a treatment strategy has not been established. Presentation of case An 81-year-old woman presented with an irreducible tender mass that was subsequently diagnosed as an incarcerated femoral hernia with a subcutaneous abscess in the right groin. Intraoperative findings revealed a necrotic and perforated appendix strangulated by the femoral ring for which an appendectomy and herniorrhaphy was performed concurrently through the hernia sac. The subcutaneous abscess cavity was washed thoroughly and a drainage tube was placed within it. The patient recovered uneventfully. Discussion We suggest that the approach through the inguinal incision in both appendectomy and herniorrhaphy with drainage may be useful in avoiding intra-abdominal contamination in cases of de Garengeot hernia with subcutaneous abscess. Conclusion Here, we described a case of de Garengeot hernia with a subcutaneous abscess in the groin. Clinicians should consider de Garengeot hernia in patients with a groin hernia, make an early diagnosis, and promptly provide surgical treatment to reduce the risk of complications.

In the neocortex, both layer 2/3 and layer 5 contain corticocortical pyramidal cells projecting to other cortices. We previously found that among L5 pyramidal cells of the secondary motor cortex (M2), not only intratelencephalic projection cells but also pyramidal tract cells innervate ipsilateral cortices and that the two subtypes are different in corticocortical projection diversity and axonal laminar distributions. Layer 2/3 houses intratelencephalically projecting pyramidal cells that also innervate multiple ipsilateral and contralateral cortices. However, it remained unclear whether layer 2/3 pyramidal cells can be divided into projection subtypes each with distinct innervation to specific targets. In the present study we show that layer 2 pyramidal cells are organized into subcircuits on the basis of corticocortical projection targets. Layer 2 corticocortical cells of the same projection subtype were monosynaptically connected. Between the contralaterally and ipsilaterally projecting corticocortical cells, the monosynaptic connection was more common from the former to the latter. We also found that ipsilaterally and contralaterally projecting corticocortical cell subtypes differed in their morphological and physiological characteristics. Our results suggest that layer 2 transfers separate outputs from M2 to individual cortices and that its subcircuits are hierarchically organized to form the discrete corticocortical outputs. NEW & NOTEWORTHY Pyramidal cell subtypes and their dependent subcircuits are well characterized in cortical layer 5, but much less is understood for layer 2/3. We demonstrate that in layer 2 of the rat secondary motor cortex, ipsilaterally and contralaterally projecting corticocortical cells are largely segregated. These layer 2 cell subtypes differ in dendrite morphological and intrinsic electrophysiological properties, and form subtype-dependent connections. Our results suggest that layer 2 pyramidal cells form distinct subcircuits to provide discrete corticocortical outputs.

The hypothesis that the basal-ganglia direct and indirect pathways represent goodness (or benefit) and badness (or cost) of options, respectively, explains a wide range of phenomena. However, this hypothesis, named the Opponent Actor Learning (OpAL), still has limitations. Structurally, the OpAL model does not incorporate differentiation of the two types of cortical inputs to the basal-ganglia pathways received from intratelencephalic (IT) and pyramidal-tract (PT) neurons. Functionally, the OpAL model does not describe the temporal-difference (TD)-type reward-prediction-error (RPE), nor explains how RPE is calculated in the circuitry connecting to the DA neurons. In fact, there is a different hypothesis on the basal-ganglia pathways and DA, named the Cortico-Striatal-Temporal-Difference (CS-TD) model. The CS-TD model differentiates the IT and PT inputs, describes the TD-type RPE, and explains how TD-RPE is calculated. However, a critical difficulty in this model lies in its assumption that DA induces the same direction of plasticity in both direct and indirect pathways, which apparently contradicts the experimentally observed opposite effects of DA on these pathways. Here, we propose a new hypothesis that integrates the OpAL and CS-TD models. Specifically, we propose that the IT-basal-ganglia pathways represent goodness/badness of current options while the PT-indirect pathway represents the overall value of the previously chosen option, and both of these have influence on the DA neurons, through the basal-ganglia output, so that a variant of TD-RPE is calculated. A key assumption is that opposite directions of plasticity are induced upon phasic activation of DA neurons in the IT-indirect pathway and PT-indirect pathway because of different profiles of IT and PT inputs. Specifically, at PT→indirect-pathway-medium-spiny-neuron (iMSN) synapses, sustained glutamatergic inputs generate rich adenosine, which allosterically prevents DA-D2 receptor signaling and instead favors adenosine-A2A receptor signaling. Then, phasic DA-induced phasic adenosine, which reflects TD-RPE, causes long-term synaptic potentiation. In contrast, at IT→iMSN synapses where adenosine is scarce, phasic DA causes long-term synaptic depression via D2 receptor signaling. This new Opponency & Temporal-Difference (OTD) model provides unique predictions, part of which is potentially in line with recently reported activity patterns of neurons in the globus pallidus externus on the indirect pathway.

Serum carbohydrate antigen 19-9 (CA 19-9), a marker of malignant tumors, is generally slightly elevated in benign conditions. We report a case of acute cholecystitis with a significantly elevated level of serum CA 19-9 based on positron emission tomography (PET)-computed tomography (CT) findings. A 65-year-old woman presented with abdominal pain and fever. A CT image revealed an enlarged gallbladder without tumor shadows. The C-reactive protein (CRP) level was elevated to 7.66 mg/dl. Moreover, the serum CA 19-9 level was significantly elevated to 19,392 U/ml. We started antibiotic treatment, because we suspected acute cholecystitis, but still, we could not ignore the possible presence of malignant tumors. After 11 days of antibiotic treatment, serum CRP and CA 19-9 levels decreased to 0.11 mg/dl and 1,049 U/ml, respectively. There was an accumulation of fluorine 18-labeled fluorodeoxyglucose (maximum standardized uptake value, 9.3) without tumor shadows in the liver, near the gallbladder, on the PET-CT examination. We considered the possibility that the inflammation had spread from the gallbladder to the liver, made a diagnosis of acute cholecystitis, and performed a cholecystectomy 33 days after treatment initiation. The serum CA 19-9 level decreased to 45 U/ml after the surgery. One year after the surgery, the patient was alive, and the serum CA 19-9 level was 34 U/ml. Acute cholecystitis with a significantly high elevation of the serum CA 19-9 level is rare. In such cases, it is important to confirm the change in the serum CA 19-9 level over time after antibiotic treatment and perform imaging studies to distinguish between inflammation and malignancy.

Summary The thalamus is the hub through which neural signals are transmitted from the basal ganglia and cerebellum to the neocortex. However, thalamocortical axonal activity during motor learning remains largely undescribed. We conducted two-photon calcium imaging of thalamocortical axonal activity in the motor cortex of mice learning a self-initiated lever-pull task. Layer 1 (L1) axons came to exhibit activity at lever-pull initiation and termination, while layer 3 (L3) axons did so at lever-pull initiation. L1 population activity had a sequence structure related to both lever-pull duration and reproducibility. Stimulation of the substantia nigra pars reticulata activated more L1 than L3 axons, whereas deep cerebellar nuclei (DCN) stimulation did the opposite. Lesions to either the dorsal striatum or the DCN impaired motor learning and disrupted temporal dynamics in both layers. Thus, layer-specific thalamocortical signals evolve with the progression of learning, which requires both the basal ganglia and cerebellar activities.

Precise regulation of migration termination is crucial for the establishment of cortical laminar structure. However, little is known about how neurons terminate migration. Here we analyzed the role of Plexin A2 and A4 (PlxnA2/A4) receptors and Semaphorin 6A (Sema6A) ligand on this process, focusing on an interaction between migrating neurons and their substrates. In PlxnA2/A4 double-knockout as well as Sema6A mutant mice, a superficial layer neurons subset ectopically invades layer I. This abnormality manifests at a time when these neurons arrive at their destinations. PlxnA2/A4 proteins are abundant on their leading processes, while Sema6A mRNA is enriched in somata of radial glial cells. Cell-targeted gene expression and conditional knockouts confirm that these molecules are required in their respective cells. Collectively, these results suggest that the well-timed appearance of the repulsive signaling mediated by Sema6A-PlxnA2/A4 weakens the interaction between migrating neurons and radial glial cells, which leads to migration termination.

KRAS gene mutations are found in 40–50 % of colorectal cancer cases, but their functional contribution is not fully understood. To address this issue, we generated genetically engineered mice with colon tumors expressing an oncogenic Kras G12D allele in the context of the Adenomatous polyposis coli (Apc) deficiency to compare them to tumors harboring Apc deficiency alone. CDX2P9.5-G22Cre (referred to as G22Cre) mice showing inducible Cre recombinase transgene expression in the proximal colon controlled under the CDX2 gene promoter were intercrossed with Apc flox/flox mice and LSL-Kras G12D mice carrying loxP-flanked Apc and Lox–Stop–Lox oncogenic Kras G12D alleles, respectively, to generate G22Cre;Apc flox/flox ;Kras G12D and G22Cre;Apc flox/flox ;KrasWT mice. Gene expression profiles of the tumors were analyzed using high-density oligonucleotide arrays. Morphologically, minimal difference in proximal colon tumor was observed between the two mouse models. Consistent with previous findings in vitro, Glut1 transcript and protein expression was up-regulated in the tumors of G22Cre;Apc flox/flox ;Kras G12D mice. Immunohistochemical staining analysis revealed that GLUT1 protein expression correlated with KRAS mutations in human colorectal cancer. Microarray analysis identified 11 candidate genes upregulated more than fivefold and quantitative PCR analysis confirmed that Aqp8, Ttr, Qpct, and Slc26a3 genes were upregulated 3.7- to 30.2-fold in tumors with mutant Kras. These results demonstrated the validity of the G22Cre;Apc flox/flox ;Kras G12D mice as a new mouse model with oncogenic Kras activation. We believe that this model can facilitate efforts to define novel factors that contribute to the pathogenesis of human colorectal cancer with KRAS mutations.

The purpose of this study is to evaluate a spiral groove geometry for a thrust bearing to improve the hemolysis level in a hydrodynamically levitated centrifugal blood pump. We compared three geometric models: (i) the groove width is the same as the ridge width at any given polar coordinate (conventional model); (ii) the groove width contracts inward from 9.7 to 0.5 mm (contraction model); and (iii) the groove width expands inward from 0.5 to 4.2 mm (expansion model). To evaluate the hemolysis level, an impeller levitation performance test and in vitro hemolysis test were conducted using a mock circulation loop. In these tests, the driving conditions were set at a pressure head of 200 mm Hg and a flow rate of 4.0 L/min. As a result of the impeller levitation performance test, the bottom bearing gaps of the contraction and conventional models were 88 and 25 μm, respectively. The impeller of the expansion model touched the bottom housing. In the hemolysis test, the relative normalized index of hemolysis (NIH) ratios of the contraction model in comparison with BPX-80 and HPM-15 were 0.6 and 0.9, respectively. In contrast, the relative NIH ratios of the conventional model in comparison with BPX-80 and HPM-15 were 9.6 and 13.7, respectively. We confirmed that the contraction model achieved a large bearing gap and improved the hemolysis level in a hydrodynamically levitated centrifugal blood pump.

There are two prevailing notions regarding the involvement of the corticobasal ganglia system in value‐based learning: (i) the direct and indirect pathways of the basal ganglia are crucial for appetitive and aversive learning, respectively, and (ii) the activity of midbrain dopamine neurons represents reward‐prediction error. Although (ii) constitutes a critical assumption of (i), it remains elusive how (ii) holds given (i), with the basal‐ganglia influence on the dopamine neurons. Here we present a computational neural‐circuit model that potentially resolves this issue. Based on the latest analyses of the heterogeneous corticostriatal neurons and connections, our model posits that the direct and indirect pathways, respectively, represent the values of upcoming and previous actions, and up‐regulate and down‐regulate the dopamine neurons via the basal‐ganglia output nuclei. This explains how the difference between the upcoming and previous values, which constitutes the core of reward‐prediction error, is calculated. Simultaneously, it predicts that blockade of the direct/indirect pathway causes a negative/positive shift of reward‐prediction error and thereby impairs learning from positive/negative error, i.e. appetitive/aversive learning. Through simulation of reward‐reversal learning and punishment‐avoidance learning, we show that our model could indeed account for the experimentally observed features that are suggested to support notion (i) and could also provide predictions on neural activity. We also present a behavioral prediction of our model, through simulation of inter‐temporal choice, on how the balance between the two pathways relates to the subject's time preference. These results indicate that our model, incorporating the heterogeneity of the cortical influence on the basal ganglia, is expected to provide a closed‐circuit mechanistic understanding of appetitive/aversive learning.

Most glutamatergic inputs in the neocortex originate from the thalamus or neocortical pyramidal cells. To test whether thalamocortical afferents selectively innervate specific cortical cell subtypes and surface domains, we investigated the distribution patterns of thalamocortical and corticocortical excitatory synaptic inputs in identified postsynaptic cortical cell subtypes using intracellular and immunohistochemical staining combined with confocal laser scanning and electron microscopic observations in 2 thalamorecipient sublayers, lower layer 2/3 (L2/3b) and lower layer 5 (L5b) of rat frontal cortex. The dendrites of GABAergic parvalbumin (PV) cells preferentially received corticocortical inputs in both sublayers. The somata of L2/3b PV cells received thalamic inputs in similar proportions to the basal dendritic spines of L2/3b pyramidal cells, whereas L5b PV somata were mostly innervated by cortical inputs. The basal dendrites of L2/3b pyramidal and L5b corticopontine pyramidal cells received cortical and thalamic glutamatergic inputs in proportion to their local abundance, whereas crossed-corticostriatal pyramidal cells in L5b exhibited a preference for thalamic inputs, particularly in their distal dendrites. Our data demonstrate an exquisite selectivity among thalamocortical afferents in which synaptic connectivity is dependent on the postsynaptic neuron subtype, cortical sublayer, and cell surface domain.

Excitatory cortical neurons project to various subcortical and intracortical regions, and exhibit diversity in their axonal connections. Although this diversity may develop from primary axons, how many types of axons initially occur remains unknown. Using a sparse-labeling in utero electroporation method, we investigated the axonal outgrowth of these neurons in mice and correlated the data with axonal projections in adults. Examination of lateral cortex neurons labeled during the main period of cortical neurogenesis (E11.5-E15.5) indicated that axonal outgrowth commonly occurs in the intermediate zone. Conversely, the axonal direction varied; neurons labeled before E12.5 and the earliest cortical plate neurons labeled at E12.5 projected laterally, whereas neurons labeled thereafter projected medially. The expression of Ctip2 and Satb2 and the layer destinations of these neurons support the view that lateral and medial projection neurons are groups of prospective subcortical and callosal projection neurons, respectively. Consistently, birthdating experiments demonstrated that presumptive lateral projection neurons were generated earlier than medial projection neurons, even within the same layer. These results suggest that the divergent axonal connections of excitatory cortical neurons begin from two types of primary axons, which originate from two sequentially generated distinct subpopulations: early-born lateral (subcortical) and later-born medial (callosal) projection neuron groups.

We have developed a hydrodynamically levitated centrifugal pump as a bridge-to-decision device. The purpose of the present study is to determine the optimal bearing gap of a multiarc radial bearing in the developed blood pump for the reduction of hemolysis. We prepared eight pump models having bearing gaps of 20, 30, 40, 80, 90, 100, 180, and 250 μm. The driving conditions were set to a pressure head of 200 mm Hg and a flow rate of 4 L/min. First, the orbital radius of the impeller was measured for the evaluation of the impeller stability. Second, the hemolytic property was evaluated in an in vitro hemolysis test. As a result, the orbital radius was not greater than 15 μm when the bearing gap was between 20 and 100 μm. The relative normalized index of hemolysis (NIH) ratios in comparison with BPX-80 were 37.67 (gap: 20 μm), 0.95 (gap: 30 μm), 0.96 (gap: 40 μm), 0.82 (gap: 80 μm), 0.77 (gap: 90 μm), 0.92 (gap: 100 μm), 2.76 (gap: 180 μm), and 2.78 (gap: 250 μm). The hemolysis tended to increase at bearing gaps of greater than 100 μm due to impeller instability. When the bearing gap decreased from 30 to 20 μm, the relative NIH ratios increased significantly from 0.95 to 37.67 times (P

Cortical fast-spiking (FS) interneurons are electrically interconnected through gap junctions and form dendritic net structures extending over different functional columns. Here we investigated how pyramidal cells regulate FS cell network activity. Using paired recordings and glutamate puff stimulations, we found that FS cell pairs connected by electrical synapses shared common inputs from surrounding pyramidal cells more frequently than those unconnected or connected only by chemical synapses. Experimental and simulation results suggest that activity spread evoked by common inputs to electrically connected FS cells depends on network state. When cells were in the depolarized state, common inputs to electrically connected cells enhanced spike induction and induced inhibitory effects in surrounding FS cells. By contrast, in the hyperpolarized state, either sub- or suprathreshold inputs produced depolarizing potentials in nearby cells. Our results suggest that globally connected FS cell networks are locally regulated by pyramidal cells in an electrical connection- and network state-dependent manner.

Higher-order motor cortices, such as the secondary motor area (M2) in rodents, select future action patterns and transmit them to the primary motor cortex (M1). To better understand motor processing, we characterized "top-down" and "bottom-up" connectivities between M1 and M2 in the rat cortex. Somata of pyramidal cells (PCs) in M2 projecting to M1 were distributed in lower layer 2/3 (L2/3) and upper layer 5 (L5), whereas PCs projecting from M1 to M2 had somata distributed throughout L2/3 and L5. M2 afferents terminated preferentially in upper layer 1 of M1, which also receives indirect basal ganglia output through afferents from the ventral anterior and ventromedial thalamic nuclei. On the other hand, M1 afferents terminated preferentially in L2/3 of M2, a zone receiving indirect cerebellar output through thalamic afferents from the ventrolateral nucleus. While L5 corticopontine (CPn) cells with collaterals to the spinal cord did not participate in corticocortical projections, CPn cells with collaterals to the thalamus contributed preferentially to connections from M2 to M1. L5 callosal projection (commissural) cells participated in connectivity between M1 and M2 bidirectionally. We conclude that the connectivity between M1 and M2 is directionally specialized, involving specific PC subtypes that selectively target lamina receiving distinct thalamocortical inputs.

Thrombus formation in blood pumps is a major problem. It has been reported that the shear rate is closely related to thrombus formation in blood pumps; however, the mechanism of blood coagulation in a shear flow field is not yet fully understood. The purpose of this study is to evaluate the effect of shear loading on the reaction of blood coagulation factors quantitatively. Human blood and porcine blood were used as test blood and sheared at 2,880 s-1 for 3 h using a rheometer. After shear loading to the test blood, the activated partial thromboplastin time (APTT) and prothrombin time (PT) of sample plasma were measured using an automated coagulation analyzer. The APTT and PT of mixed plasma containing human blood coagulation factor-deficient plasma and sample plasma were also measured. The APTT and PT of mixed plasma reflected the reaction of the particular blood coagulation factor. Results show that shear loading prolonged the APTT and PT of human sample plasma. Accordingly, the APTT and PT of mixed plasma containing human blood coagulation factor V-deficient plasma and human sample plasma were prolonged after shear loading. Thus, the reaction of human blood coagulation factors was inhibited by specific inhibition of the reaction of human blood coagulation factor V in the shear flow field. The reaction time of porcine blood coagulation factors after shear loading differed from that of human blood coagulation factors. The result suggest the evaluation difficulty of animal blood coagulation reaction, that is, porcine blood coagulation reaction did not fully proceed with clinical reagents due to species specificity.

Jiang et al . (Research Article, 27 November 2015, aac9462) describe detailed experiments that substantially add to the knowledge of cortical microcircuitry and are unique in the number of connections reported and the quality of interneuron reconstruction. The work appeals to experts and laypersons because of the notion that it unveils new principles and provides a complete description of cortical circuits. We provide a counterbalance to the authors’ claims to give those less familiar with the minutiae of cortical circuits a better sense of the contributions and the limitations of this study.

Background Laparoscopic surgery has spread quickly during the past twenty years, and has become one of the important treatments in the field of colorectal surgery. Recently, natural orifice transluminal endoscopic surgery (NOTES) has been studied as the next generation of minimally-invasive surgery, but the feasibility and safety of the NOTES method have not been evaluated. In such a situation, single-incision laparoscopic surgery has attracted interest from surgeons worldwide. However, single-incision laparoscopic colorectal surgery has not yet been standardized. Methods From February 2010, single-incision laparoscopic colectomy was performed for 7 patients presenting with early colon cancer. All procedures were performed by two experts with the License of Endoscopic Surgical Skill Qualification System (ESSQS) of Japan Society for Endoscopic Surgery (JSES) in the field of colorectal Surgery. Results We used the Gelport system (Applied Medical, Rancho Santa Margarita, CA, USA) as the access port and 3 trocars of different sizes (Ethicon, Inc., Cincinnati, OH, USA). Using this technique, we did not experience any difficulties or use any articulated instruments. All of the present 7 patients underwent the single-incision laparoscopic colectomy successfully and had no complications. Conclusion: Single-incision laparoscopic surgery using the Gelport was performed safely in the present cases. The use of the Gelport as an access port can address the technical difficulty associated with this new technique.

An 18-year-old girl presented with abdominal pain and a tumor was subsequently detected in the jejunum. We therefore carried out a wedge resection of the jejunum. The diagnosis of GIST was confirmed histologically, and a mutation in exon 9 of the c-kit gene was observed. GISTs are rare in pediatric populations and pediatric GISTs occur predominantly in females and are characterized by a multifocal gastric location and a wild-type phenotype for the c-kit genes. The features of pediatric GISTs of the small intestine have not yet been categorized, and to date, only 11 cases in patients younger than 18 years have been reported. These cases did not occur primarily in females and tended to present as single tumors with mutations in the c-kit gene. This suggests that these cases do not have the same features as pediatric gastric GISTs, but instead are similar to adult GISTs. In pediatric populations, GISTs of the small intestine were expected to show a better response to imatinib treatment than gastric GISTs because of the alterations in the c-kit gene.

目的:下部直腸腫瘍に対する部分的内肛門括約筋切除術（partial intersphinteric resection;p-ISR）の術後排便機能，quality of life（QOL）を従来の肛門括約筋全温存術（ultra low anterior resection;ULAR）と比較検討した．対象と方法:下部直腸腫瘍に対してp-ISR及びULARを施行した計27症例の術後排便機能およびQOLをアンケートで評価した．結果:p-ISR群12例，ULAR群15例であった．肛門縁から腫瘍下端までの距離は36.9mmと61.0mmでp-ISR群が有意に低い位置にあった．術後Wexner scoreはp-ISR群で高い傾向にあったが，術後3カ月のみ有意差を認めた．排便回数は両群間に差は認めなかった．術後QOLはSF-36の各項目に両群間で有意差を認めなかった．結語:p-ISR後の排便機能はULARと比較して便失禁が多い傾向にあるもののQOLに差を認めなった．今後さらに症例を蓄積した検討が必要である．

遺伝性非ポリポーシス大腸癌（HNPCC）は若年·多発癌発症などの特長があり発症者や保因者の同定は重要である．しかし，一般臨床において十分に拾い上げが行われているとはいえない．我々は独自に，認知しやすい拾い上げ基準（広島大学基準）を設定し拾い上げを試みた．広島大学基準は（1）50歳以下（2）多発癌（3）多臓器重複癌のいずれかを満たすものとし，2003年1月から2007年5月に当科で手術を施行した原発性結腸·直腸癌症例372例を対象に検討を行った．拾い上げ基準に合致した95例のうち希望した25例に遺伝子カウンセリングを行い，その中の18例に遺伝子検査を行った．その結果18例中7例にHNPCC関連遺伝子の異常を認め，18例中広島大学基準のみを満たした7例のうち2例にhMLH1の異常を認めた．一般臨床での認知と適切な拾い上げにより保因者を特定し，治療およびサポートを行う臨床的意義は大きいと考えられた．

Although neocortical GABAergic (gamma-aminobutyric acidergic) interneurons have been the focus of intense study, especially in the rat, a consensus view of the functional diversity and organization of inhibitory cortical neurons has not yet been achieved. To better analyze GABAergic neurons in the rat, we used a bacterial artificial chromosome (BAC) construct and established 2 lines of transgenic rats that coexpress Venus, a yellow fluorescent protein, with the vesicular GABA transporter. The brain GABA content from both transgenic lines was similar to the level found in wild-type rats. In the frontal cortex, Venus was expressed in >95% of GABAergic neurons, most of which also expressed at least one of 6 biochemical markers, including alpha-actitin-2, which preferentially labeled late-spiking neurogliaform cells. Taking advantage of the fact that Venus expression allows for targeted recording from all classes of nonpyramidal cells, irrespective of their somatic morphologies, we demonstrated that fast-spiking neurons, which were heterogeneous in somatic size as well as vertical dendritic projection, had relatively uniform horizontal dimensions, suggesting a cell type-specific columnar input territory. Our data demonstrate the benefits of VGAT-Venus rats for investigating GABAergic circuits, as well as the feasibility of using BAC technology in rats to label subsets of specific, genetically defined neurons.

Acetylcholine (ACh) is a neurotransmitter critical for normal cognition. Here we demonstrate heterogeneity of cholinergic signaling in neocortical neurons in the rat prefrontal, somatosensory, and visual cortex. Focal ACh application (100 μM) inhibited layer 5 pyramidal neurons in all cortical areas via activation of an apamin-sensitive SK-type calcium-activated potassium conductance. Cholinergic inhibition was most robust in prefrontal layer 5 neurons, where it relies on the same signal transduction mechanism (M1-like receptors, IP3-dependent calcium release, and SK-channels) as exists in somatosensory pyramidal neurons. Pyramidal neurons in layer 2/3 were less responsive to ACh, but substantial apamin-sensitive inhibitory responses occurred in deep layer 3 neurons of the visual cortex. ACh was only inhibitory when presented near the somata of layer 5 pyramidal neurons, where repetitive ACh applications generated discrete inhibitory events at frequencies of up to ∼0.5 Hz. Fast-spiking (FS) nonpyramidal neurons in all cortical areas were unresponsive to ACh. When applied to non-FS interneurons in layers 2/3 and 5, ACh generated mecamylamine-sensitive nicotinic responses (38% of cells), apamin-insensitive hyperpolarizing responses, with or without initial nicotinic depolarization (7% of neurons), or no response at all (55% of cells). Responses in interneurons were similar across cortical layers and regions but were correlated with cellular physiology and the expression of biochemical markers associated with different classes of nonpyramidal neurons. Finally, ACh generated nicotinic responses in all layer 1 neurons tested. These data demonstrate that phasic cholinergic input can directly inhibit projection neurons throughout the cortex while sculpting intracortical processing, especially in superficial layers.

Inhibitory interneurons target precise membrane regions on pyramidal cells, but differences in their functional effects on somata, dendrites and spines remain unclear. We analyzed inhibitory synaptic events induced by cortical, fast-spiking (FS) basket cells which innervate dendritic shafts and spines as well as pyramidal cell somata. Serial electron micrograph (EMg) reconstructions showed that somatic synapses were larger than dendritic contacts. Simulations with precise anatomical and physiological data reveal functional differences between different innervation styles. FS cell soma-targeting synapses initiate a strong, global inhibition, those on shafts inhibit more restricted dendritic zones, while synapses on spines may mediate a strictly local veto. Thus, FS cell synapses of different sizes and sites provide functionally diverse forms of pyramidal cell inhibition. DOI: http://dx.doi.org/10.7554/eLife.07919.001, eLife digest The brain contains millions of cells called neurons that communicate with one another as part of complex circuits. To send information around these circuits, neurons ‘fire’ electrical signals along their length. These trigger the release of chemicals across a structure—known as the synapse—that forms a connection with a neighboring cell. Different types of neurons affect their neighbors in different ways. For example, signals from a pyramidal cell make it more likely that the next cell in the circuit will fire, whereas a signal sent by an inhibitory interneuron has the opposite effect. Pyramidal cells and interneurons make up the circuits in the brain's outer layer—the cortex. Despite their opposing roles, these cells share the same basic structure. Each consists of a cable-like axon that can efficiently transmit electrical signals, and a cell body that contains the nucleus. The cell body bears numerous short branches called dendrites, which are in turn covered in bump-like protrusions called spines. Synapses typically form between the end of one cell's axon and a dendrite on another cell. However, synapses can also form between the end of an axon and an individual dendritic spine, or the end of an axon and a cell body. Models of inhibitory synapses—connections from interneurons that inhibit pyramidal cells—tend to assume that these three types of connection are equivalent. However, Kubota et al. have now combined electron microscopy with electrode recordings of the activity of pairs of connected cells to show that the size and ability of inhibitory synapses to inhibit signaling varies depending on their location. Specifically, inhibitory synapses that form with the cell bodies of pyramidal cells are larger and inhibit signaling more strongly than those that form with dendrites, which are in turn larger and more inhibitory than those on dendritic spines. Thus, depending on the point at which an interneuron contacts a pyramidal cell, it can inhibit signaling throughout the entire cell body, or only across a dendrite, or even just within a single dendritic spine. Incorporating this information into computer models of the brain will improve how accurately they simulate how the brain works. It will also help when modeling disorders in which inhibitory networks are disrupted, such as schizophrenia and depression. DOI: http://dx.doi.org/10.7554/eLife.07919.002

It remains controversial whether open or laparoscopic surgery should be indicated for elderly patients with colorectal cancer and a poor performance status. In those patients aged 80 years or older with Eastern Cooperative Oncology Group performance status score of 2 or greater who received elective surgery for stage 0 to stage III colorectal adenocarcinoma and had no concomitant malignancies and who were enrolled in a multicenter case–control study entitled “Retrospective study of laparoscopic colorectal surgery for elderly patients” that was conducted in Japan between 2003 and 2007, background characteristics and short-term and long-term outcomes for open surgery and laparoscopic surgery were compared. Of the 398 patients included, 295 underwent open surgery and 103 underwent laparoscopic surgery. There were no significant differences in the baseline characteristics between open surgery and laparoscopic surgery patients, except for previous abdominal surgery and TNM stage. The median operation duration was shorter with open surgery (open surgery, 153 min; laparoscopic surgery, 202 min; P

The gastrointestinal tract is continuously exposed to a variety of chemicals and commensal bacteria. Recent studies have shown that changes in gut microbial populations caused by chlorine or other chemicals in the drinking water influence the development of human colorectal cancer, although the mechanism of tumorigenesis in the gut epithelium is obfuscated by the diversity of microflora and complexity of the tumor microenvironment. In this regard, mouse models that recapitulate human colorectal cancer are an invaluable tool. In this study, we used two conditional adenomatous polyposis coli (Apc) knockout mouse models to investigate the effect of chlorinated water on tumorigenesis in the digestive tract. Mice with colon-specific carcinoma--caused by either chromosomal (CDX2P 9.5-NLS Cre;Apc(+/flox), abbreviated to CPC;Apc) or microsatellite (CDX2P9.5-G19Cre;Apc(flox/flox) and CDX2P9.5-G22Cre;Apc(flox/flox)) instability, respectively--were administered chlorinated (10.0 mg/L chlorine) or tap (0.7 mg/L chlorine) water and evaluated for colon polyp formation. In CPC;Apc mice given chlorinated drinking water, tumors tended to develop in the colon, whereas in those that drank tap water, tumors were mostly observed in the small intestine. There was no difference in the rate of tumor formation of CDX2P9.5-G19Cre;Apc(flox/flox) and CDX2P9.5-G22Cre;Apc(flox/flox) mice consuming chlorinated as compared to tap water, suggesting that microsatellite instability in the Apc gene does not significantly affect tumorigenesis. Chlorinated water altered the enteric environment by reducing the fecal populations of the obligatory anaerobes Clostridium perfringens and C. difficile, as well as species belonging to the Atopobium cluster, including Enterobacteriaceae and Staphylococcus sp., which was associated with colon tumorigenesis in CPC;Apc mice. These results suggest that differences in tumorigenesis among CPC;Apc mice consuming chlorinated versus tap water may be due to differences in gastrointestinal commensal populations.

This Frontiers Research Topic on “Neural Circuits: Japan” explores the diversity of innovative neural circuit research occurring across Japan. This issue brings together papers revealing the development, structure, and physiology of neuronal circuits involved in sensory perception, sleep and wakefulness, behavioral selection, and motor command generation in a range of species, from nematode to primate. One area of interest includes cerebellar local and efferent circuits, as well as mechanisms underlying synaptic plasticity in Purkinje cells, which have been a focus of intensive investigation by many Japanese researchers. Long-term depression at connections between parallel fibers and Purkinje cells is thought to play a critical role in motor learning. In mice without Cbln1, delay eye blink conditioning, as well as LTD at the parallel fiber to Purkinje cell synapse, were impaired, even as previously formed conditioning responses were retained, suggesting a necessity for LTD selectively in conditioning formation (Emi et al., 2013). The cerebellar cortex is composed of functionally different microzones. Investigation of microzonal organization in glutamate receptor δ2 knockout mice revealed that proper innervation by individual climbing fibers is necessary for functional microzone formation (Hashizume et al., 2013). In dystonia, the cerebellum as well as the basal ganglia may be involved in its pathogenesis. Deletion of type 1 inositol 1,4,5-trisphosphate receptors in the cerebellum induced dystonic movements and abnormal movement-coupled firing in Purkinje cells, while inactivation of the inferior olive suppressed abnormal movements. These results suggest the involvement of the olivo-cerebellar pathway in dystonia (Hisatsune et al., 2013). For analysis of synaptic plasticity in the cerebral cortex, diverse imaging techniques and optical probes have been used. Among them, Forster resonance energy transfer (FRET), combined with newly developed probes, will greatly contribute to our understanding of synaptic plasticity mechanisms at the molecular level (Ueda et al., 2013). During normal formation of cortical circuits, axons and dendrites need to generate boutons and spines at proper locations, respectively. In the cerebral cortex, collateralization of thalamocortical fibers depends on concentrations of brain-derived neurotrophic factor (BDNF), and this BDNF-dependent collateralization was absent after suppression of synaptic vesicle recycling (Granseth et al., 2013). In hippocampal CA3 neurons, application of corticosterone increased the density of dendritic thorny excrescences in pyramidal cells for short time. Similarly, acute stress increases the connectional strength of dentate gyrus to CA3 synapses (Yoshiya et al., 2013). Neocortical pyramidal cells are composed of multiple subtypes that differ in their subcortical projection targets. The subtype composition of layer 5 pyramidal cells connecting cortical areas is also variable, and depends on the target area (Ueta et al., 2013). These observations suggest that cortical neurons are selectively connected according to their individual identities. Further, the temporal pattern of spike discharges may reflect the connectional selectivity of cortical neurons. Large scale activity recordings in the CA3 region of the hippocampus have revealed that temporal firing sequences among a given group of pyramidal cells are repeated among spontaneous spikes of hippocampal neurons ex vivo (Matsumoto et al., 2013). Compared to projections from the retina to primary visual cortex (V1), connections between higher visual centers are less understood. In mice, axons from V1 respond differently to visual input depending on their projection to higher visual areas (Matsui and Ohki, 2013). These results suggest that different V1 cells with distinct visual responses project to different higher visual areas. In Drosophila, analysis of visual stimuli-dependent behaviors revealed visual response differences among higher visual centers (Otsuna et al., 2014). On the other hand, in the olfactory system, newly generated neurons are continually integrated into neuronal circuits, and the survival of new neurons is dependent on sleep following food consumption. The olfactory bulb and cortex are suitable for the analysis of sleep-dependent plastic mechanisms in the brain (Yamaguchi et al., 2013). To understand the switching mechanism between sleep and wakefulness, it is necessary to understand the synaptic interactions between hypothalamic nuclei participating this process. Optogenetic analysis has revealed inhibitory connections from GABAergic cells in the preoptic area to Orexin cells in the lateral hypothalamic area (Saito et al., 2013). The planning and execution of behavior require computation in the basal ganglia and frontal cortex, as well as cortical output to the spinal cord. Conventional electrophysiological and anatomical methods have proven insufficient to clarify these complex circuits. On the other hand, the combined use of local transfection and retrograde transport of viruses were able to block synaptic outputs in the crossed tecto-reticular pathway to suppress motor function (Sooksawate et al., 2013). The combination of retrogradely-transported virus and immunotoxins have also successfully blocked synaptic transmission from motor-related cortical areas to the subthalamic nucleus (Takada et al., 2013). Pathway-selective inhibition using retrogradely-transported viruses will continue to be a critical tool for elucidating the functions of individual projection systems. The connection loops formed by the basal ganglia and frontal cortex participate in selection of proper movements depending on sensory information. The globus pallidus and frontal areas, such as the dorsal premotor cortex, the dorsolateral prefrontal cortex, and the ventrolateral prefrontal cortex, participate in setting behavioral goals according to cues in the external environment (Hoshi, 2013). On the other hand, C. elegans is an excellent model organism for circuit function analysis because its neuronal organization has been well-characterized, and diverse genetic manipulations are easily achievable. Using C. elegans, Japanese researchers have made significant contributions to the understanding of neural circuit that generate behaviors in response to sensory information such as odor and temperature (Sasakura et al., 2013). Thus, as in the USA and Europe, researchers in Japan are now focusing efforts to elucidate the function of neural circuits in diverse organisms by taking advantage of optogenetics, genetic manipulations, and traditional physiological and anatomical approaches, as well as neural pathway-selective inactivation techniques that have recently been developed in Japan.

To understand the dendritic differentiation in various types of cortical nonpyramidal cells, we analyzed quantitatively their dendritic branching and spine expression. The dendritic internode and interspine interval obeyed exponential distributions with type-specific decay constants. The initial branching pattern, internode interval and spine density at the light microscopic level divided nonpyramidal cells into three dendritic types, correlated with axonal, neurochemical and firing types. The initial branching pattern determined the overall vertical spread of dendrites. Basket cell subtypes with different firing and chemical expression patterns were distinct in the vertical and horizontal spatial spread, providing diverse input territories. Internode densities of dendritic spines, as well as those of axonal synaptic boutons, did not correlate with the tortuosities and intervals, suggesting a tendency to distribute synapses homogeneously over the arbor. Dendritic spines identified at the electron microscopic level were different in length and shape among subtypes. Although the density was lower than that of pyramidal cells, spines themselves were also composed of several morphological types such as mushroom and multihead ones, which were expressed differentially among subtypes. Correlation of dendritic branching characteristics with differences in spine structure suggests distinct ways to receive specific inputs among the subtypes.

GABAergic nonpyramidal cells, cortical interneurons, consist of heterogeneous subtypes differing in their axonal field and target selectivity. It remains to be investigated how the diverse innervation patterns are generated and how these spatially complicated, but synaptically specific wirings are achieved. Here, we asked whether a particular cell type obeys a specific branching and bouton arrangement principle or differs from others only in average morphometric values of the morphological template common to nonpyramidal cells. For this purpose, we subclassified nonpyramidal cells within each physiological class by quantitative parameters of somata, dendrites, and axons and characterized axon branching and bouton distribution patterns quantitatively. Each subtype showed a characteristic set of vertical and horizontal bouton spreads around the somata. Each parameter, such as branching angles, internode or interbouton intervals, followed its own characteristic distribution pattern irrespective of subtypes, suggesting that nonpyramidal cells have the common mechanism for formation of the axon branching pattern and bouton arrangement. Fitting of internode and interbouton interval distributions to the exponential indicated their apparent random occurrence. Decay constants of the fitted exponentials varied among nonpyramidal cells, but each subtype expressed a particular set of interbouton and internode interval averages. The distinctive combination of innervation field shape and local axon phenotypes suggests a marked functional difference in the laminar and columnar integration properties of different GABAergic subtypes, as well as the subtype-specific density of inhibited targets.

It remains to be clarified how many classes of GABAergic nonpyramidal cells exist in the cortical circuit. We have divided GABA cells in the rat frontal cortex into 3 groups, based on their firing characteristics: fast-spiking (FS) cells, late-spiking (LS) cells, and non-FS cells. Expression of calcium-binding proteins and peptides could be shown in separate groups of GABA cells in layers II/III and V of the frontal cortex: (1) parvalbumin cells, (2) somatostatin cells, (3) calretinin and/or vasoactive intestinal polypeptide (VIP) cells [partially positive for cholecystokinin (CCK)] and (4) large CCK cells (almost negative for VIP/calretinin). Combining the physiological and chemical properties of morphologically diverse nonpyramidal cells allows division into several groups, including FS basket cells containing parvalbumin, non-FS somatostatin Martinotti cells with ascending axonal arbors, and non-FS large basket cells positive for CCK. These subtypes show characteristic spatial distributions of axon collaterals and the innervation tendency of postsynaptic elements. With synchronized activity induced by cortical excitatory or inhibitory circuits, firing patterns were also found to differ. Subtype-selective occurrence of electrical coupling, finding for potassium channel Kv3.1 proteins, and cholinergic and serotonergic modulation supports our tentative classification. To clarify the functional architecture in the frontal cortex, it is important to reveal the connectional characteristics of GABA cell subtypes and determine whether they are similar to those in other cortical regions.

Cholinergic inputs from the basal forebrain to cortex exert profound effects on cortical activities, such as a rhythmic synchronization. For these modulatory effects inhibitory interneurons could play crucial roles within the cortical circuitry. To study cholinergic modulation of GABA-mediated inhibition, we recorded inhibitory postsynaptic current (IPSC) during application of cholinergic agonists in the rat frontal cortex in vitro. Both carbachol and muscarine caused two temporally different patterns of IPSC modulation in both pyramidal cells and inhibitory interneurons: tonic or periodic increase of GABA-A receptor-mediated inhibition. The tonic pattern showed a continuous increase of IPSC frequency, while the periodic increase manifested itself as rhythmic (0.1-0.3 Hz, mean 0.2 Hz) bursts of IPSC (frequency: 6-69 Hz, mean 24 Hz; burst duration: 1.2-4.3 s, mean 2.2 s). Both types of increase were suppressed by atropine or pirenzepine, muscarinic-receptor antagonists. The periodical IPSC bursts were not affected by antagonists for ionotropic glutamate receptors. Following cholinergic stimulation, periodic IPSC bursts in nearby cells were synchronized as a whole, but individual inhibitory events within the bursts were not always temporally correlated, suggesting synchronized depolarizations of several presynaptic interneurons. It has been revealed that slow rhythmic depolarizations accompanying spike firing can be generated within the cortex. In addition to this periodic excitation of cortical circuits, these results indicate that cortical inhibitory interneurons have their own acetylcholine-dependent mechanism generating the slow rhythm independent of the excitatory circuits.

The safety of laparoscopic surgery (LAP) in elderly patients with colorectal cancer has not been demonstrated. The aim of this study was to compare the outcomes of LAP and open surgery (OP) and estimate the feasibility of LAP in colorectal cancer patients aged ≥80 years. We conducted a propensity scoring matched case–control study of colon and rectal cancer patients aged ≥80 years using data from 41 hospitals between 2003 and 2007. A total of 1,526 colon cancer patients and 282 rectal cancer patients underwent surgery and were included in the analysis. The primary end point was 3-year overall survival (OS). Secondary end points included disease-free survival (DFS), cancer-specific survival (CSS), and postoperative complications. LAP and OP were compared in 804 colon cancer patients (402 pairs) and 114 rectal cancer patients (57 pairs) after all covariates were balanced, and no significant differences were observed, except for tumor size in colon cancer. OS, DFS, and CSS did not differ between the groups for either colon cancer (P = 0.916, 0.968, and 0.799, respectively) or rectal cancer (P = 0.765, 0.519, and 0.950, respectively). In colon cancer cases, LAP was associated with fewer morbidities than was OP (24.9 vs. 36.3 %, P

The frontal cortex plays an important role in the initiation and execution of movements via widespread projections to various cortical and subcortical areas. Layer 2/3 (L2/3) pyramidal cells in the frontal cortex send axons mainly to other ipsilateral/contralateral cortical areas. Subpopulations of layer 5 (L5) pyramidal cells that selectively project to the pontine nuclei or to the contralateral cortex [commissural (COM) cells] also target diverse and sometimes overlapping ipsilateral cortical areas. However, little is known about target area-dependent participation in ipsilateral corticocortical (iCC) connections by subclasses of L2/3 and L5 projection neurons. To better understand the functional hierarchy between cortical areas, we compared iCC connectivity between the secondary motor cortex (M2) and adjacent areas, such as the orbitofrontal and primary motor cortices, and distant non-frontal areas, such as the perirhinal and posterior parietal cortices. We particularly assessed the laminar distribution of iCC cells and fibers, and identified the subtypes of pyramidal cells participating in those projections. For connections between M2 and frontal areas, L2/3 and L5 cells in both areas contributed to reciprocal projections, which can be viewed as “bottom-up” or “top-down” on the basis of their differential targeting of cortical lamina. In connections between M2 and non-frontal areas, neurons participating in bottom-up and top-down projections were segregated into the different layers: bottom-up projections arose primarily from L2/3 cells, while top-down projections were dominated by L5 COM cells. These findings suggest that selective participation in iCC connections by pyramidal cell subtypes lead to directional connectivity between M2 and other cortical areas. Based on these findings, we propose a provisional unified framework of interareal hierarchy within the frontal cortex, and discuss the interaction of local circuits with long-range interareal connections.

In the neostriatum, several types of interneuron with distinct firing patterns and expression of neuroactive substances are known to exist. We found two types of neostriatal interneurons, parvalbumin-containing fast-spiking (FS) cells and somatostatin-containing low-threshold spike (LTS) cells to both be immunoreactive for GABA at their axon terminals in immersion-fixed brain slices from rat. To reveal the differences in synaptic connections between these two types of GABAergic interneurons, the postsynaptic target and their synaptic structure were compared by three-dimensional reconstructions from electron microscopic images of intracellularly stained axon terminals. FS cells made a greater proportion of synaptic contacts onto somata than LTS cells. Although terminal boutons of FS and LTS cells were similar in volume, their synaptic junctional areas differed in size distribution and relation to the dimensions of postsynaptic dendritic shafts or spines. Whereas the synaptic junctional areas of FS cells (0.024–0.435 μm2;n= 28) sharply and linearly increased with the circumference of the postsynaptic dendrites or spines (0.939–5.146 μm), the slope for the junctional area of LTS cells (0.02–0.103 μm2;n= 29) against circumference (0.844–4.252 μm) was less steep, and a much weaker correlation was seen. In addition to the differences in firing patterns, expressed molecules, axonal arborizations, and postsynaptic targets, this variation in dependency of the synaptic area on the target size suggests functional differentiation of GABAergic interneurons.

BACKGROUND Transabdominal ultrasonography (US) has been widely accepted as a diagnostic method with which to examine multiple organs simultaneously. This study was designed to evaluate the efficacy of trans-abdominal US to screen for urogenital malignancies. METHODS From 1993 through 1997 109,077 men and 28,023 women underwent abdominal US to screen for abdominal and pelvic diseases as part of a regular health check-up program at the Tokyu Medical Health Center. RESULTS Twelve renal cell cancers (RCCs), 7 bladder tumors (BTs), 4 prostatic cancers (PCs), and 1 testicular tumor (TT) were detected. All cancers were diagnosed pathologically and treated surgically except for one PC. Surgical pathological examination and conventional imaging revealed that all 12 RCCa and 6 of the 7 BTs were of less advanced stage than pT1N0M0. However, all 3 PCs and the TT were pT3N0-1M0 and pT1N3M0, respectively. The stage and grade of these 12 RCCs were significantly lower than those of 29 symptomatic RCCs. All 12 patients with RCC patients and 6 of the 7 patients with BT had no urological symptom, whereas 3 of the 4 patients with PC and the patient with TT had urogenital symptoms. Microscopic examination of the urine revealed both red blood cells and tumors cells in two of the seven patients with BT. All four patients with PC had serum levels of prostatic-specific antigen greater than 4 ng/ml. CONCLUSION These results indicate that screening by transabdominal US as part of regular health check-ups can detect many types of urogenital malignancy. In particular, US is useful for detecting low-grade and low-stage RCCs and superficial BTs but is less sensitive for early-stage PCs and TTs.

The aim of this study was to elucidate electrophysiologically the actions of dopamine and SKF38393, a D1-like dopamine receptor agonist, on the membrane excitability of striatal large aspiny neurons (cholinergic interneurons). Whole-cell and perforated patch-clamp recordings were made of striatal cholinergic neurons in rat brain slice preparations. Bath application of dopamine (1–100 μm) evoked a depolarization/inward current with an increase, a decrease, or no change in membrane conductance in a dose-dependent manner. This effect was antagonized by SCH23390, a D1-like dopamine receptor antagonist. The current–voltage relationships of the dopamine-induced current determined in 23 cells suggested two conductances. In 10 cells the current reversed at −94 mV, approximately equal to the K+equilibrium potential (EK); in three cells theI–Vcurves remained parallel, whereas in 10 cells the current reversed at −42 mV, which suggested an involvement of a cation permeable channel. Change in external K+concentration shifted the reversal potential as expected forEkin low Na+solution. The current observed in 2 mmBa2+-containing solution reversed at −28 mV. These actions of dopamine were mimicked by application of SKF38393 (1–50 μm) or forskolin (10 μm), an adenylyl cyclase activator, and were blocked by SCH23390 (10 μm) or SQ22536 (300 μm), an inhibitor of adenylyl cyclase. These data indicate, first, that dopamine depolarizes the striatal large aspiny neurons by a D1-mediated suppression of resting K+conductance and an opening of a nonselective cation channel and, second, that both mechanisms are mediated by an adenylyl cyclase-dependent pathway.

Physiological and morphological properties of large non-pyramidal cells immunoreactive for cholecystokinin, parvalbumin or somatostatin were investigated in vitro in the frontal cortex of 18-22-day-old rats. These three peptides were expressed in separate populations including large cells. Cholecystokinin cells and parvalbumin cells made boutons apposed to other cell bodies, but differed in their firing patterns in response to depolarizing current pulses. Parvalbumin cells belonged to fast-spiking cells. Parvalbumin fast-spiking cells also included chandelier cells. In contrast, cholecystokinin cells were found to be regular-spiking non-pyramidal cells or burst-spiking non-pyramidal cells with bursting activity from hyperpolarized potentials (two or more spikes on slow depolarizing humps). Large somatostatin cells belonged to the regular-spiking non-pyramidal category and featured wide or ascending axonal arbors (wide arbor cells and Martinotti cells) which did not seem to be apposed to the somata so frequently as large cholecystokinin and parvalbumin cells. For electron microscopic observations, another population of eight immunohistochemically-uncharacterized non-pyramidal cells were selected: (i) five fast spiking cells including one chandelier cell which are supposed to contain parvalbumin, and (ii) three large regular-spiking non-pyramidal cells with terminals apposed to somata, which are not considered to include somatostatin cells, but some of which may belong to cholecystokinin cells. The fast-spiking cells other than a chandelier cell and the large regular-spiking non-pyramidal cells made GABA-positive synapses on somata (4% and 12% of the synapses in two small to medium fast-spiking cells, 22% and 35% of the synapses in two large fast-spiking cells, and 10%, 18% and 37% of the synapses in three large regular-spiking non-pyramidal cells). A few terminals of the fast-spiking and regular-spiking non-pyramidal cells innervated GABAergic cells. About 30% of the fast-spiking cell terminals innervated spines, but few of the regular-spiking non-pyramidal cell terminals did. A fast-spiking chandelier cell made GABA-positive synapses on GABA-negative axon initial segments. These results suggest that large GABAergic cells are heterogeneous in neuroactive substances, firing patterns and synaptic connections, and that cortical cells receive heterogeneous GABAergic somatic inputs.

Physiological, morphological and immunohistochemical characteristics of non-pyramidal cells in frontal cortex of young rats were studied in vitro by whole-cell recording and biocytin injection. Several groups of GABAergic non-pyramidal cells were identified: (i) parvalbumin fast-spiking (FS) cells with low input resistances and spikes of short duration, including extended plexus (basket) cells and chandelier cells. These cells showed abrupt episodes of non-adapting repetitive discharges; (ii) late-spiking (LS) cells exhibiting slowly developing ramp depolarizations, including neurogliaform cells; (iii) the remaining groups contained both burst-spiking (BS) or regular-spiking (RS) non-pyramidal (NP) cells. BSNP cells exhibited bursting activity (two or more spikes on slow depolarizing humps) from hyperpolarized potentials. Both these physiological types corresponded to a range of morphologies: (i) somatostatin-containing Martinotti cells with ascending axonal arbors to layer I (some were also positive for calbindin D28k); (ii) VIP-containing double bouquet cells with descending axonal arbors as well as arcade cells (these included small cells immunoreactive for CCK or calretinin). Each subtype of cells made GABAergic synapses onto relatively specific portions of cortical cells, but similar domains were innervated by multiple classes of GABA cells.

The neostriatum is considered to be involved in the induction of purposeful movements or in the suppression of other movements through the internal segment of the globus pallidus (GP; the entopeduncular nucleus in the rodents) and the substantia nigra (SN) to which the striatal spiny neurons project. To understand how the striatum fulfills these functions, it is necessary to know the physiological and morphological characteristics of its constituent neurons. Aspiny interneurons in the striatum are considered to receive various excitatory inputs and to contribute importantly to determining whether spiny projection neurons fire or not. Both spiny and aspiny striatal cells have been shown to be heterogeneous in their physiological, chemical and connection characteristics. In this article, how these cell subtypes are organized in the local circuitry of the striatum and their physiological roles in the basal ganglia are discussed.

The purpose of the present study is to establish an optimal design of the multi-arc hydrodynamic bearing in a centrifugal blood pump for the improvement of bearing stiffness and hemolysis level. The multi-arc bearing was designed to fulfill the required specifications: (i) ensuring the uniform bearing stiffness for various bearing angles; (ii) ensuring a higher bearing stiffness than the centrifugal force to prevent impeller whirl; and (iii) adjusting the bearing clearance as much as possible to reduce hemolysis. First, a numerical analysis was performed to optimize three design parameters of the multi-arc bearing: number of arcs N, bearing clearance C, and groove depth H. To validate the accuracy of the numerical analysis, the impeller trajectories for six pump models were measured. Finally, an in vitro hemolysis test was conducted to evaluate the hemolytic property of the multi-arc bearing. As a result of the numerical analysis, the optimal parameter combination was determined as follows: N=4, C=100 μm, and H ≥ 100 μm. In the measurements of the impeller trajectory, the optimal parameter combination was found to be as follows: N=4, C=90 μm, and H=100 μm. This result demonstrated the high reliability of the numerical analysis. In the hemolysis test, the parameter combination that achieved the smallest hemolysis was obtained as follows: N=4, C=90 μm, and H=100 μm. In conclusion, the multi-arc bearing could be optimized for the improvement of bearing stiffness and hemolysis level.