Earthquake experience interference effects in a modified Stroop task: An ERP study

The effects of the modified Stroop task on ERP were investigated in 20 subjects who had experienced the Sichuan earthquake and a matched control group. ERP data showed that Incongruent stimuli elicited a more negative ERP deflection (N300–450) than did Congruent stimuli between 300 and 450 ms post-stimulus in the earthquake group but not found in the control group, and the N300–450 might reflect conflict monitor (the information of color and meaning do not match) in the early phase of perception identification due to their sensitivity to the external stimulus. Then, Incongruent stimuli elicited a more negative ERP deflection than did Congruent stimuli between 450 and 650 ms post-stimulus in both the groups. Dipole source analysis showed that the N450–650 was mainly generated in the ACC contributed to this effect in the control group, which might be related to monitor and conflict resolution. However, in the earthquake group, the N450–650 was generated in the thalamus, which might be involved in inhibiting and compensating of the ACC which may be related to conflict resolution process.     

An fMRI study of neuronal specificity of an acupoint: Electroacupuncture stimulation of Yanglingquan (GB34) and its sham point

The neuronal specificity of acupoints has not been entirely supported by the results of fMRI studies. The objective of this study was to investigate the neuronal specificity of an acupoint with electroacupuncture stimulation (EAS) using functional magnetic resonance imaging (fMRI). Functional MR imaging of the entire brain was performed in 12 normal healthy subjects during EAS of GB34 (Yanglingquan) and its sham point over the left leg in counter-balanced order. Anatomically, both GB34 and its sham point belong to the L5 spinal segment. EAS at the left GB34 specifically activated the right putamen, caudate body, claustrum, thalamus, cerebellum, as well as the left caudate body, ventral lateral thalamus, and cerebellum, all related to motor function. EAS at the sham point of the left GB34 specifically activated the right BA6, BA8, BA40, BA44, thalamus, as well as the left thalamus and cerebellum. Taken together, these findings suggest that EAS at an acupoint and its sham point, in the same spinal segment, induced specific cerebral response patterns. These findings support neuronal specificity of the acupoint studied. EAS at GB34 appears to be more related to motor function than EAS at its sham point, suggesting specificity of the GB34 acupoint. The results of this study provide neurobiological evidence for the existence of acupoint specificity, although further studies are necessary to better understand this phenomenon.     

Inter-individual differences in the habitual use of cognitive reappraisal and expressive suppression are associated with variations in prefrontal cognitive control for emotional information: An event related fMRI study

Two different emotion regulation strategies, cognitive reappraisal and expressive suppression, are strongly associated with increased neural activity in the prefrontal cognitive control network. In this event-related fMRI study, we investigated whether individual differences in habitual reappraisal and suppression tendencies are related to differences in prefrontal cognitive control processes for emotional information. In order to measure cognitive control over inhibiting a dominant response to happy or sad stimuli (in favor of the opposite valence), thirty-one healthy female participants performed the Cued Emotional Conflict Task (CECT). The Emotion Regulation Questionnaire was used to measure individual differences in everyday use of emotion regulation. Results demonstrate that high reappraisers are behaviorally faster and exert more fronto-cingulate activity when inhibiting a response to sad faces (compared to happy faces, FDR corrected). On the other hand, suppression scores are not correlated with performance to CECT trials. Interestingly, suppression scores are associated with higher amygdala activation during the inhibition of a response to sad faces (compared to happy faces). These data suggest that habitual reappraisal is associated with underlying functional cognitive control processes to inhibit a dominant response to negative material. In contrast, the effort to control negative material has negative consequences in individuals who have a tendency to suppress emotions.     

An immunohistochemical study of bizarre neoplastic cells in pleomorphic adenoma: its cytological nature and proliferative activity

The cytological nature and proliferative activity of bizarre neoplastic cells, widely scattered in pleomorphic adenomas of salivary gland origin were studied. Pleomorphic adenomas containing numerous bizarre neoplastic cells were found in four cases, and were equal to 2.9% of all pleomorphic adenomas examined. All four cases presented as well-circumscribed, firm masses measuring less than 1.5 cm in size, located in the palate, and were of 7 months to 4 years duration. Histopathologically, these pleomorphic adenomas were cell rich type, and were well demarcated from surrounding tissues, although their fibrous capsules were partially defective. In addition to characteristic histopathological findings of pleomorphic adenoma, numerous neoplastic cells with bizarre appearance were scattered throughout the lesion, excepting for tubuloductal structures. These bizarre neoplastic cells had irregular-shaped and large nuclei with or without hyperchromatism, although their nucleoli were small and mitotic figures were few. Furthermore, there were many multinucleated giant cells, some of which showed multilobulated nuclei. Neither necrosis nor infarct was seen in the tumors. Immunohistochemically, bizarre neoplastic cells scattered in solid-proliferating areas and myxoid areas were neoplastic myoepithelial cells in nature. There was no statistical significance of MIB-1 labeling indices between pleomorphic adenomas with bizarre neoplastic cells and usual pleomorphic adenomas. The p53 labeling indices were quite low. Although the benign nature of pleomorphic adenomas with numerous bizarre neoplastic cells and hypercellularity, distinguishing such pleomorphic adenomas from various stages of malignant transformation in pleomorphic adenomas and other carcinomas should be made by histological section of submitted biopsy specimen or aspirated content for cytological diagnosis. The present paper suggests that the term 'bizarre cell pleomorphic adenoma' is an appropriate name for this neoplasm, in that it is distinguished from the usual benign pleomorphic adenoma which is easily diagnosed by routinely prepared histological or cytological stainings.     

Morphological and physiological properties of neostriatal neurons: An intracellular horseradish peroxidase study in the rat

The physiological and morphological (light and electron microscopic) properties of four categories of neostriatal neurons (two types of medium spiny cells and two types of aspiny cells) were analyzed using the technique of intracellular recording and intracellular labeling with horseradish peroxidase. All of the neurons in this study had excitatory responses following stimulation of the cortex and substantia nigra except for the large aspiny neuron for which only substantia nigra inputs were tested. Morphologically, these neurons differed with respect to the size and shape of their somata, density and distribution of dendritic spines and distribution of their axons and axon collaterals. Ultrastructurally, observed somatic differences included the quantity and distribution of organelles and conformation of the nuclear envelope.The axons of one type of medium spiny neuron and the large aspiny neuron were myelinated. Unmyelinated axon collaterals arose from the axons of both types of medium spiny neurons and formed synapses on the dendritic shafts and possibly with the necks of spines of other neostriatal neurons. The parent axons of the most common type of medium spiny neurons were followed to the globus pallidus and, in some cases, to the internal capsule.     

Interactions between Fab and Fc regions in liganded immunoglobulin G: A study employing the antigenic polymorphism and multivalency of the human red-cell membrane

Previous studies indicated that the inter-y chain disulphide bonds restrict segmental flexibility within the Fc region of human IgG; the present study suggests that there are also non-covalent hinge-region restrictions of flexibility in the liganded molecule. Staphylococcus aureas protein A-Sepharose-passed F(ab′)₂ fragments from IgG fractions of blood-group antisera were tested in parallel with the parent antibodies in haemagglutination tests. At molar-equivalence in protein, the titre of F(ab′)₂ from incomplete antibodies was 2- to 3-fold greater than the titre of the intact antibody (p < 0.001). Increased activity occurred whether enzyme or albumin techniques were used to convert the incomplete antibodies to agglutinins, and was particularly striking with Kell blood-group antibodies where F(ab′)₂ fragments were weak saline agglutinins. Antiglobulin tests, using anti-κ, revealed small differences in intrinsic antigenbinding activity between IgG and F(ab′)₂ fractions, but these differences were either of inverse relationship or insufficient to account for the increased agglutinating activity of F(ab′)₂ compared with the whole molecule. By contrast, with IgG saline agglutinins [anti-κ (anti-glycophorin A^M) and anti-B], the apparent freedom introduced by peptic removal of Fc, or by reduction of interchain disulphide bonds, was inimical to agglutination, as would be predicted from other studies (Hornick & Karush, 1972; Crothers & Metzger, 1972). These results show that the Fe region imposes limitations on full segmental flexibility of Fab regions in liganded IgG.A comparison of the intrinsic and functional antigen-binding activities of IgG anti-M and anti-B confirmed that both antibodies engage in substantial monogamous bivalency. That the relative monogamous bivalency of F(ab′)₂ and IgG anti-M was unaffected by an increased mean separation of M sites on the cell surface suggests that it is predominantly dimers of glycophorin a^M, in situ, which generate the monogamous bivalency and that, on M/N red cells, some glycophorin-A^M molecules are associated as homologous dimers. For IgG anti-A and anti-B, the known decreased affinity with A₂ and A₁B red cells can be explained by the fewer opportunities for monogamous bivalency. Using the increased flexibility in F(ab′)₂ and reduced-alkylated IgG anti-D as molecular probes for spatial relationships between D antigens, (i) a marked deviation from an average separation of antigens was found on normal red cells under conditions of agglutination, and (ii) an early effect of trypsin-treatment (< 2 min) which permits limited redistribution of D sites was detected.Mildly reduced IgG3 exhibited significantly greater flexibility than reduced IgG1, presumably reflecting the extended γ3 hinge region. Unreduced IgG3, however, did not show the increased Fab-region flexibility shown by F(ab′)₂ fragments on the IgG1 sub-class. In reduced IgG molecules, Cγ2 and Cγ3 domains retained much of their native surface topography.     

Identification of germ cells at risk for neoplastic transformation in gonadoblastoma: an immunohistochemical study for OCT3/4 and TSPY

Carcinoma in situ (CIS) is the precursor of malignant testicular germ cell tumors (GCTs) of adolescents and young adults, being the neoplastic counterpart of primordial germ cells/gonocytes. Carcinoma in situ cells will develop into invasive seminoma/nonseminoma. Gonadoblastoma (GB) is the precursor of invasive GCTs in dysgenetic gonads, predominantly dysgerminoma (DG). In this process, part of the Y chromosome (GBY region) is involved, for which TSPY is a candidate gene. A detailed immunohistochemical survey was performed for the known diagnostic markers, germ cell/placental alkaline phosphatase (PLAP), c-KIT, and OCT3/4, as well as testis-specific protein on the Y chromosome (TSPY) on a series of GBs, and adjacent invasive DGs. All 5 patients were XY individuals (4 females and 1 male). In contrast to c-KIT, PLAP was positive in all cases. The immature germ cells of GBs were positive for OCT3/4, whereas the mature germ cells were negative for this marker, but positive for TSPY. In every GB, a minor population of germ cells positive for both markers could be identified, similar to most CIS cells and early invasive DG. On progression to an invasive tumor, TSPY can be lost, a process that is also detectable in invasive testicular GCTs compared to CIS. These results indicate that GB is a heterogeneous mix of germ cells, in which the OCT3/4-positive cells have the potential to undergo progression to an invasive tumor. These early invasive stages are initially also positive for TSPY (like CIS), supporting a positive selection mechanism. Therefore, OCT3/4 in combination with TSPY is valuable to identify malignant germ cells in dysgenetic gonads. This could allow better prediction of the risk of progression to a GCT. In addition, the data support the model that GB represents the earliest accessible developmental stage of malignant GCTs.