Ensemble dynamics and information flow deduction from whole-brain imaging data

The recent advancements in large-scale activity imaging of neuronal ensembles offer valuable opportunities to comprehend the process involved in generating brain activity patterns and understanding how information is transmitted between neurons or neuronal ensembles. However, existing methodologies for extracting the underlying properties that generate overall dynamics are still limited. In this study, we applied previously unexplored methodologies to analyze time-lapse 3D imaging (4D imaging) data of head neurons of the nematode Caenorhabditis elegans. By combining time-delay embedding with the independent component analysis, we successfully decomposed whole-brain activities into a small number of component dynamics. Through the integration of results from multiple samples, we extracted common dynamics from neuronal activities that exhibit apparent divergence across different animals. Notably, while several components show common cooperativity across samples, some component pairs exhibited distinct relationships between individual samples. We further developed time series prediction models of synaptic communications. By combining dimension reduction using the general framework, gradient kernel dimension reduction, and probabilistic modeling, the overall relationships of neural activities were incorporated. By this approach, the stochastic but coordinated dynamics were reproduced in the simulated whole-brain neural network. We found that noise in the nervous system is crucial for generating realistic whole-brain dynamics. Furthermore, by evaluating synaptic interaction properties in the models, strong interactions within the core neural circuit, variable sensory transmission and importance of gap junctions were inferred. Virtual optogenetics can be also performed using the model. These analyses provide a solid foundation for understanding information flow in real neural networks.

Neuron ID dataset facilitates neuronal annotation for whole-brain activity imaging of C. elegans

BACKGROUND

Annotation of cell identity is an essential process in neuroscience that allows comparison of cells, including that of neural activities across different animals. In Caenorhabditis elegans, although unique identities have been assigned to all neurons, the number of annotatable neurons in an intact animal has been limited due to the lack of quantitative information on the location and identity of neurons.

RESULTS

Here, we present a dataset that facilitates the annotation of neuronal identities, and demonstrate its application in a comprehensive analysis of whole-brain imaging. We systematically identified neurons in the head region of 311 adult worms using 35 cell-specific promoters and created a dataset of the expression patterns and the positions of the neurons. We found large positional variations that illustrated the difficulty of the annotation task. We investigated multiple combinations of cell-specific promoters driving distinct fluorescence and generated optimal strains for the annotation of most head neurons in an animal. We also developed an automatic annotation method with human interaction functionality that facilitates annotations needed for whole-brain imaging.

CONCLUSION

Our neuron ID dataset and optimal fluorescent strains enable the annotation of most neurons in the head region of adult C. elegans, both in full-automated fashion and a semi-automated version that includes human interaction functionalities. Our method can potentially be applied to model species used in research other than C. elegans, where the number of available cell-type-specific promoters and their variety will be an important consideration.

Female pseudohermaphroditism associated with maternal steroid cell tumor, not otherwise specified of the ovary: a case report and literature review

Maternal virilization in pregnancy with or without fetal female pseudohermaphroditism has several etiologies. Of these, pregnancy luteoma is the most common cause of maternal virilization during pregnancy, and approximately 20 cases have been reported in recent years. Moreover, four cases of pregnancy luteomas with female pseudohermaphroditism have been reported. However, the extremely rare steroid cell tumor, not otherwise specified (NOS), has been reported only once as a cause for maternal virilization. Herein, the authors report the first case of maternal virilization with female pseudohermaphroditism associated with steroid cell tumor-NOS along with the clinical course, pathological features, and a review of the literature.

Predicting nedaplatin sensitivity of cervical cancer using the histoculture drug response assay

PURPOSE

There are currently no clinically available chemosensitivity assays for cervical cancer. In this study we evaluated whether the histoculture drug response assay (HDRA) could be used to predict chemosensitivity to nedaplatin (NDP) in cervical cancer.

METHODS

Fifty-four surgical specimens and biopsies from patients with squamous cell carcinoma of the cervix were tested with the HDRA. The results were used to calculate the concentration resulting in 50% inhibition of tumor growth (IC50). We then determined the cut-off concentration for NDP, and investigated the chemosensitivity of NDP for each patient. Moreover, the correlations between chemosensitivity and the clinical response of NDP-containing chemotherapy, and the clinical outcomes of the patients with Stage I and II disease were also investigated.

RESULTS

Fifty-one of 54 specimens (94.0%) were evaluable with this assay. The optimal cutoff concentration of NDP was determined to be 48 microg/ml. In 18 patients with measurable lesions, all nine patients in the high sensitive group by HDRA were judged as partial response (PR) to NDP containing chemotherapy. In contrast five of nine patients in the low sensitive group were classified as stable disease, and four were PR. The true positive rate was 100%, the true negative rate was 55.6%, and the accurate prediction rate was 77.8%. Furthermore, the disease-free survival of the high sensitive group tended to be better than that of the low sensitive group in the patients who received postoperative adjuvant chemotherapy with NDP.

CONCLUSIONS

In the current study, the sensitivity of cervical tumors to nedaplatin was predicted by the HDRA.

Continuous intravenous infusion of deleted form of hepatocyte growth factor attenuates hepatic ischemia-reperfusion injury in rats

BACKGROUND/AIMS

Although beneficial roles of hepatocyte growth factor (HGF) and its variants on several hepatic disorders have been reported, their effects on hepatic ischemia-reperfusion (IR) injury remain undetermined. We investigated the action of a deleted form of HGF (dHGF) on hepatic IR injury in rats.

METHODS

dHGF or phosphate-buffered saline was continuously infused intravenously for 20 h prior to a 20-min occlusion of hepatic vessels. Samples were taken before and after IR, for measurement of serum dHGF and released enzymes, liver gamma-glutamylcysteinyl glycine (GSH) level, as well as histological and immunohistochemical examinations.

RESULTS

After reperfusion, histological injury, as well as increase in the serum activities of aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, and creatine kinase-BB were significantly attenuated in the dHGF-treated rats. dHGF maintained a high GSH level and suppressed oxidative stress and intercellular adhesion molecule-1 (ICAM-1) expression on sinusoidal endothelial cells (SECs), on which c-Met was not detected. IR caused activation of c-Met expression, which was milder in the dHGF-treated group, in hepatocytes at the pericentral region.

CONCLUSIONS

dHGF attenuated liver injury after IR. It also maintained a higher GSH level, depressed oxidative stress and inhibited ICAM-1 expression on c-Met negative SECs, suggesting a paracrine effect of dHGF.

Microwave Spectrum, Structure, and Nuclear Quadrupole Coupling Constants of 1-Bromo-1-fluoroethane

The microwave spectrum of 1-bromo-1-fluoroethane, CHBrF-CH(3) and CHBrF-CH(2)D ((79/81)Br), has been studied for the first time from 8 to 41 GHz. A least-squares analysis of the observed a- and b-type transition frequencies gave rotational and centrifugal distortion constants and components of the bromine nuclear quadrupole coupling constant tensor in the principal axes system as follows: A = 8979.428(5) MHz, B = 2883.898(3) MHz, C = 2310.535(3) MHz, Delta(J) = 0.74(2) kHz, Delta(JK) = 2.49(3) kHz, Delta(K) = 5.3(5) kHz, delta(J) = 0.146(1) kHz, delta(K) = 2.75(4) kHz, chi(aa) = 493.49(29) MHz, chi(bb) - chi(cc) = -38.89(11) MHz, and ||chi(ab) || = 161.8(28) MHz for the CH(79)BrF-CH(3) species; A = 8979.257(5) MHz, B = 2859.072(3) MHz, C = 2294.572(3), Delta(J) = 0.76(2) kHz, Delta(JK) = 2.51(3) kHz, Delta(K) = 4.5(4) kHz, delta(J) = 0.145(1) kHz, delta(K) = 2.70(4) kHz, chi(aa) = 412.42(27) MHz, chi(bb) - chi(cc) = -32.56 (11) MHz, and ||chi(ab) || = 133.3(3) MHz for the CH(81)BrF-CH(3) species. The structural parameters are calculated from the 24 observed rotational constants, and electronic properties of the carbon-bromine bond in 1-bromo-1-fluoroethane are evaluated from the observed nuclear quadrupole coupling constants. These molecular properties are compared with those of other related molecules. The molecular structure of 1-bromo-1-fluoroethane is found to be very close to that of 1,1-difluoroethane except for the C-Br bond. Copyright 1999 Academic Press.

Microwave Spectrum, Nuclear Quadrupole Coupling Constants, and Structure of Bromodifluoromethane

The microwave spectrum of bromodifluoromethane, CHBrF2 (Halon 1201) has been studied for the first time from 7 to 40 GHz. A least-squares analysis of the observed c-type transition frequencies gave rotational and centrifugal distortion constants and components of the bromine nuclear quadrupole coupling constant tensor in the principal axes system as follows: A = 10199.7186(62) MHz, B = 2903.4150(26) MHz, C = 2360.1521(23) MHz, DeltaJ = 0.660(14) kHz, DeltaJK = 2.87(11) kHz, DeltaK = 8.95 kHz, deltaJ = 0.1344(24) kHz, deltaK = 3.22(15) kHz, chiaa = 521.281(92) MHz, chibb - chicc = -38.32(9) MHz, and |chiac| = 187.1(26) MHz for the 79Br species; A = 10199.5567(54) MHz, B = 2876.5588(20) MHz, C = 2342.3796(18) MHz, DeltaJ = 0.652(12) kHz, DeltaJK = 2.77(9) kHz, DeltaK = 8.21(61) kHz, deltaJ = 0.1300(19) kHz, deltaK = 2.97(13) kHz, chiaa = 435.61(10) MHz, chibb - chicc = -32.08(8) MHz, and |chiac| = 148.5(29) MHz for the 81Br species. The structural parameters are calculated from all these rotational constants and the electronic properties of the carbon-bromine bond in bromodifluoromethane are evaluated from the observed nuclear quadrupole coupling constants. These molecular properties are compared with those of other related molecules. Copyright 1997 Academic Press. Copyright 1997Academic Press

Incidental 67Ga uptake into an appendiceal mucocele in a patient with sigmoid colon cancer

We report a case of sigmoid colon cancer in which visualization of an appendiceal mucocele was unexpectedly found during 67Ga scintigraphy, and discuss a proposed mechanism of uptake.