Modeling the association between functional connectivity and lateralization with the activity flow framework

The human brain is localized and distributed. On the one hand, each cognitive function tends to involve one hemisphere more than the other, also known as the principle of lateralization. On the other hand, interactions among brain regions in the form of functional connectivity (FC) are indispensable for intact function. Recent years have seen growing interest in the association between lateralization and FC. However, FC metrics vary from spurious correlation to causal associations. If lateralization manifests local processing and causal network interactions, more causally valid FC metrics should predict lateralization index (LI) better than FC based on simple correlations. The present study directly investigates this hypothesis within the activity flow framework to compare the association between lateralization and four brain connectivity metrics: correlation-based FC, multiple-regression FC, partial-correlation FC, and combinedFC. We propose two modeling approaches: the one-step approach, which models the relationship between LI and FC directly, and the two-step approach, which predicts the brain activation and calculates the LI. Our results indicated that multiple-regression FC, partial-correlation FC, and combinedFC could significantly improve the model prediction compared to correlation-based FC, which was consistent in a spatial working memory task (typically right-lateralized) and a language task (typically left-lateralized). The one-step and two-step approach yielded similar conclusions. In addition, the finding was replicated in a clinical sample of schizophrenia (SZ), bipolar disorder (BP), and attention deficit hyperactivity disorder (ADHD). The present study suggests that the causal interactions among brain regions help shape the lateralization pattern.

Split-half reliability estimates of an online card sorting task in a community sample of young and elderly adults

Executive function is vital for normal social, cognitive, and motor functions. Executive function decline due to aging increases the risk of disability and falls in older adults, which has become an urgent public health issue. Fast and convenient neuropsychological tools are thus needed to identify high-risk groups as early as possible to conduct a timely intervention. Card sorting tasks, such as Wisconsin Card Sorting Task (WCST) and its variants, are popular tools for measuring executive function. This study investigated the reliability of an open-source, self-administered, online, short-version card sorting task with a sample of young (n = 107, 65 females, age: M = 30.1 years, SD = 5.5 years) and elderly Chinese (n = 113, 53 females, age: M = 64.0 years, SD = 6.7 years). We developed an automated scoring and visualization procedure following the recent recommendations on scoring perseverative responses to make the results comparable to the standardized WCST. Reliability estimates of commonly used measures were calculated using the split-half method. All task indices' reliabilities were reasonably good in both old and young groups except for "failure-to-maintain-set." Elderly Chinese adults showed compromised task performance on all measures compared with the young Chinese adults at the group level. The R script of automated scoring and estimation of reliability is publicly available.

TSP-GNN: a novel neuropsychiatric disorder classification framework based on task-specific prior knowledge and graph neural network

Neuropsychiatric disorder (ND) is often accompanied by abnormal functional connectivity (FC) patterns in specific task contexts. The distinctive task-specific FC patterns can provide valuable features for ND classification models using deep learning. However, most previous studies rely solely on the whole-brain FC matrix without considering the prior knowledge of task-specific FC patterns. Insight by the decoding studies on brain-behavior relationship, we develop TSP-GNN, which extracts task-specific prior (TSP) connectome patterns and employs graph neural network (GNN) for disease classification. TSP-GNN was validated using publicly available datasets. Our results demonstrate that different ND types show distinct task-specific connectivity patterns. Compared with the whole-brain node characteristics, utilizing task-specific nodes enhances the accuracy of ND classification. TSP-GNN comprises the first attempt to incorporate prior task-specific connectome patterns and the power of deep learning. This study elucidates the association between brain dysfunction and specific cognitive processes, offering valuable insights into the cognitive mechanism of neuropsychiatric disease.

Explainable Alzheimer's Disease Detection Using Linguistic Features from Automatic Speech Recognition

INTRODUCTION

Alzheimer's disease (AD) is the most prevalent type of dementia and can cause abnormal cognitive function and progressive loss of essential life skills. Early screening is thus necessary for the prevention and intervention of AD. Speech dysfunction is an early onset symptom of AD patients. Recent studies have demonstrated the promise of automated acoustic assessment using acoustic or linguistic features extracted from speech. However, most previous studies have relied on manual transcription of text to extract linguistic features, which weakens the efficiency of automated assessment. The present study thus investigates the effectiveness of automatic speech recognition (ASR) in building an end-to-end automated speech analysis model for AD detection.

METHODS

We implemented three publicly available ASR engines and compared the classification performance using the ADReSS-IS2020 dataset. Besides, the SHapley Additive exPlanations algorithm was then used to identify critical features that contributed most to model performance.

RESULTS

Three automatic transcription tools obtained mean word error rate texts of 32%, 43%, and 40%, respectively. These automated texts achieved similar or even better results than manual texts in model performance for detecting dementia, achieving classification accuracies of 89.58%, 83.33%, and 81.25%, respectively.

CONCLUSION

Our best model, using ensemble learning, is comparable to the state-of-the-art manual transcription-based methods, suggesting the possibility of an end-to-end medical assistance system for AD detection with ASR engines. Moreover, the critical linguistic features might provide insight into further studies on the mechanism of AD.

The Split-Half Reliability and Construct Validity of the Virtual Reality-Based Path Integration Task in the Healthy Population

OBJECTIVE

The virtual reality (VR)-based path integration task shows substantial promise in predicting dementia risk. However, the reliability and validity in healthy populations need further exploration. The present study investigates the relationship between task indicators and brain structures in a healthy population using a VR-based navigation task, particularly the entorhinal cortex (EC) and hippocampus.

METHODS

Sixty healthy adults were randomly recruited to perform a VR-based path integration task, the digit span task (DST), and an MRI scan. The indicators of the VR-based path integration task were calculated, including the absolute distance error (ADE), degree of angle deviation (DAD), degree of path deviation (DPD), and return time (Time). The reliability of the above indicators was then estimated using the split-half method and Cronbach's alpha. Correlation and regression analyses were then performed to examine the associations between these indicators and age, general cognitive ability (DST), and brain structural measures.

RESULTS

ADE, DAD, and DPD showed reasonable split-half reliability estimates (0.84, 0.81, and 0.72) and nice Cronbach's alpha estimates (0.90, 0.86, and 0.96). All indicators correlated with age and DST. ADE and DAD were sensitive predictors of hippocampal volume, and return time was a predictor of EC thickness.

CONCLUSION

Our findings demonstrate that the VR-based path integration task exhibits good reliability and validity in the healthy population. The task indicators are age-sensitive, can capture working memory capacity, and are closely related to the integrity of individual EC and hippocampal structures.

The Cycling Brain in the Workplace: Does Workload Modulate the Menstrual Cycle Effect on Cognition?

Recent decades have witnessed increased research efforts to clarify how the menstrual cycle influence females’ cognitive and emotional functions. Despite noticeable progress, the research field faces the challenges of inconsistency and low generalizability of research findings. Females of reproductive ages are a heterogeneous population. Generalizing the results of female undergraduates to women in the workplace might be problematic. Furthermore, the critical cognitive processes for daily life and work deserve additional research efforts for improved ecological validity. Thus, this study investigates cognitive performance across the menstrual cycle using a sample of young nurses with similar duties. We developed a mini-computerized cognitive battery to assess four mental skills critical for nursing work: cognitive flexibility, divided attention, response inhibition, and working memory. Participants completed the cognitive battery at menses, late-follicular, and mid-luteal phases. In addition, they were classified into low- and high workload groups according to their subjective workload ratings. Our results demonstrate a general mid-luteal cognitive advantage. Besides, this study reveals preliminary evidence that workload modulates the menstrual cycle effect on cognition. Only females of low workload manifest the mid-luteal cognitive advantage on divided attention and response inhibition, implying that a suitable workload threshold might be necessary for regular neuro-steroid interactions. Thus, this study advocates the significance of research focusing on the cycling brain under workloads.

Early-Onset Micromorphological Changes of Neuronal Fiber Bundles During Radiotherapy

BACKGROUND

Patients receiving cranial radiation face the risk of delayed brain dysfunction. However, an early medical imaging marker is not available until irreversible morphological changes emerge.

PURPOSE

To explore the micromorphological white matter changes during the radiotherapy session by utilizing an along-tract analysis framework.

STUDY TYPE

Prospective.

POPULATION

Eighteen nasopharyngeal carcinoma (two female) patients receiving cranial radiation.

FIELD STRENGTH/SEQUENCE

3.0 T; Diffusion tensor imaging (DTI) and T1- and T2-weighted images (T1W, T2W); computed tomography (CT).

ASSESSMENT

Patients received three DTI imaging scans during the radiotherapy (RT), namely the baseline scan (1-2 days before RT began), the middle scan (the middle of the RT session), and the end scan (1-2 days after RT ended). Twelve fibers were segmented after whole-brain tractography. Then, the fractional anisotropy (FA) values and the cumulative radiation dose received for each fiber streamline were resampled and projected into their center fiber.

STATISTICAL TESTS

The contrast among the three scans (P1: middle scan-baseline scan; P2: end scan-middle scan; P3: end scan-baseline scan) were compared using the linear mixed model for each of the 12 center fibers. Then, a dose-responsiveness relationship was performed using Pearson correlation. P < 0.05 was considered statistically significant.

RESULTS

Six of the 12 center fibers showed significant changes of FA values during the RT but with heterogeneous patterns. The significant changes along a specific center fiber were associated with their cumulative dose received (Genu: P1 r = -0.6182, P2 r = -0.5907; Splenium: P1 r = 0.4055, P = 0.1063, P2 r = 0.6742; right uncinate fasciculus: P1 r = -0.3865, P2 r = -0.4912, P = 0.0533; right corticospinal tract: P1 r = 0.4273, P = 0.1122, P2 r = -0.6885).

DATA CONCLUSION

The along-tract analysis might provide sensitive measures on the early-onset micromorphological changes.

LEVEL OF EVIDENCE

2 TECHNICAL EFFICACY: Stage 3.

A role of the lateral prefrontal cortex in the congruency sequence effect revealed by transcranial direct current stimulation

Congruency effect is the increase in response time when relevant and irrelevant cues indicate incongruent rather than congruent responses. The congruency effect is smaller in the trial after an incongruent trial than after a congruent trial: this difference is known as the congruency sequence effect (CSE). Psychophysical and neural studies have suggested that the lateral prefrontal cortex (LPFC) and the medial prefrontal cortex are associated with the CSE. In the present study, we applied anodal and cathodal transcranial direct current stimulation, which is thought to result in excitation and inhibition, respectively, on the LPFC, while human participants were performing a flanker task. We found that the CSE was increased under cathodal stimulation (inhibition) of the LPFC. Moreover, the LPFC stimulation modulated the congruency effect after a congruent trial. Further analyses suggested that the results cannot be explained by any of the currently prevailing hypotheses of the CSE, including the conflict monitoring hypothesis, feature integration hypothesis, and temporal learning account. Based on our findings, we propose that a new distinct mechanism might be involved in the CSE. Specifically, the LPFC might contribute to the CSE by maintaining the attention to the task-relevant information, which is an endogenous goal-oriented function and reduces the carry-over of the task-irrelevant information after a congruent trial.

Electrical stimulation reduces smokers' craving by modulating the coupling between dorsal lateral prefrontal cortex and parahippocampal gyrus

Applying electrical stimulation over the prefrontal cortex can help nicotine dependents reduce cigarette craving. However, the underlying mechanism remains ambiguous. This study investigates this issue with functional magnetic resonance imaging. Thirty-two male chronic smokers received real and sham stimulation over dorsal lateral prefrontal cortex (DLPFC) separated by 1 week. The neuroimaging data of the resting state, the smoking cue-reactivity task and the emotion task after stimulation were collected. The craving across the cue-reactivity task was diminished during real stimulation as compared with sham stimulation. The whole-brain analysis on the cue-reactivity task revealed a significant interaction between the stimulation condition (real vs sham) and the cue type (smoking vs neutral) in the left superior frontal gyrus and the left middle frontal gyrus. The functional connectivity between the left DLPFC and the right parahippocampal gyrus, as revealed by both psychophysical interaction analysis and the resting state functional connectivity, is altered by electrical stimulation. Moreover, the craving change across the real and sham condition is predicted by alteration of functional connectivity revealed by psychophysical interaction analysis. The local and long-distance coupling, altered by the electrical stimulation, might be the underlying neural mechanism of craving regulation.

HEMOGLOBIN A1c LEVEL HIGHER THAN 9.05% CAUSES A SIGNIFICANT IMPAIRMENT OF ERYTHROCYTE DEFORMABILITY IN DIABETES MELLITUS

Context

Clinical studies demonstrated erythrocyte deformability (ED) is impaired in diabetic patients and described the correlations between HbA1c and ED. Few studies further investigated what an exact elevated HbA1c level linked to the impairment of ED in diabetes.

Objective

This study was to determine a cut-off point of HbA1c level leading to the impairment of ED in patients with diabetes.

Design

This was a retrospective observational study. ROC curve analysis was used to determine an optimal cut-off value of HbA1c for the increasing HSRV.

Subjects and Methods

In this study, 300 type 2 diabetic patients were enrolled. The whole blood viscosity was measured. High shear reductive viscosity (HSRV) was used to indirectly estimate ED. Based on the obtained cut-off value and glycemic control criteria for HbA1c, we divided all the cases into different groups to further confirm the accuracy of the cut-off value.

Results

In 300 patients, ROC curve illustrated that 9.05% was the optimal cut-off value as a predictor of the increasing HSRV. And higher odds ratio (OR) for significant decrease in ED was seen in the patients with HbA1c >9.05% compared to those with HbA1c≤9.05% (OR: 3.78, 95% CI: 2.08-6.87). HSRV increased significantly in patients with HbA1c level >9.05% in comparison to patients with HbA1c levels <6.5% between 6.5 and 8.0% and between 8.0 and 9.05%.

Conclusion

ED decreased significantly in diabetic patients as soon as HbA1c level was higher than 9.05%.

Non-invasive Brain Stimulation for the Treatment of Nicotine Addiction: Potential and Challenges

Tobacco consumption is one of the leading causes of preventable death worldwide. However, it is difficult to give up smoking by relying on the help of traditional treatments only. Recent years have witnessed emerging positive evidence that non-invasive brain stimulation (NIBS), such as transcranial magnetic stimulation and transcranial direct-current stimulation, can reduce smoking-related behaviors. Although their potential has been implied by advances in research, several methodological issues restrict the clinical application of NIBS to treating nicotine dependence. In this review, we critically evaluate related studies and give suggestions for future research and applications to meet these challenges.

Ultrastructural and Cytochemical Properties of Peripheral Blood Cells of Piebald Naked Carp (Gymnocypris eckloni)

The ultrastructural and cytochemical properties of peripheral blood cells of Gymnocypris eckloni were investigated by transmission electron microscopy and a range of cytochemical techniques to provide clear insight into the structure and function of blood cells from this fish. Ultrastructurally, erythrocytes, leucocytes (neutrophils, eosinophils, lymphocytes, monocytes), thrombocytes and plasma cells were identified in the peripheral blood of G. eckloni. The most special ultrastructural characteristics of blood cells in this fish were that neutrophils exhibited only one type of cytoplasmic granules containing an eccentric, spherical or oval electron-dense core, and eosinophils presented two types of granules with non-uniform electronic density and without crystalloids in their cytoplasm. Neutrophils, eosinophils, lymphocytes, monocytes and thrombocytes were positive for periodic acid-Schiff and α-naphthyl acetate esterase staining. Intense peroxidase positive staining was observed in neutrophils and monocytes, but not in eosinophils, lymphocytes and thrombocytes. Neutrophils, eosinophils and monocytes were stained positively for acid phosphatase, whereas lymphocytes and thrombocytes did not stain. Leucocytes and thrombocytes were negative for alkaline phosphatase and Sudan black B staining. Erythrocytes were negative for all cytochemical staining. The cytochemical and ultrastructural features of peripheral blood cells of G. eckloni were similar to those of other fish species. However, some important differences were identified in G. eckloni.

Electrical stimulation over bilateral occipito-temporal regions reduces N170 in the right hemisphere and the composite face effect

Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique that can modulate cortical excitability. Although the clinical value of tDCS has been advocated, the potential of tDCS in cognitive rehabilitation of face processing deficits is less understood. Face processing has been associated with the occipito-temporal cortex (OT). The present study investigated whether face processing in healthy adults can be modulated by applying tDCS over the OT. Experiment 1 investigated whether tDCS can affect N170, a face-sensitive ERP component, with a face orientation judgment task. The N170 in the right hemisphere was reduced in active stimulation conditions compared with the sham stimulation condition for both upright faces and inverted faces. Experiment 2 further demonstrated that tDCS can modulate the composite face effect, a type of holistic processing that reflects the obligatory attention to all parts of a face. The composite face effect was reduced in active stimulation conditions compared with the sham stimulation condition. Additionally, the current polarity did not modulate the effect of tDCS in the two experiments. The present study demonstrates that N170 can be causally manipulated by stimulating the OT with weak currents. Furthermore, our study provides evidence that obligatory attention to all parts of a face can be affected by the commonly used tDCS parameter setting.

[Effects and clinical significance of virus load on red blood cell parameters in different stage of hepatitis B]

OBJECTIVE

To evaluate the effect of the viral load on the red blood cell parameters in chronic hepatitis B patients and its clinical significance.

METHODS

In the study, 373 chronic hepatitis B patients were recruited, including 123 alanine transaminase (ALT) normal patients (ALT<40 U/L),128 ALT greater than or equal to the upper limit of normal, and less than 2 times higher than the upper limit of normal patients(40 U/L ≤ALT<80 U/L), and 122 ALT greater than or equal to 2 times higher than the upper limit of normal patients (ALT≥80 U/L). The blood routine parameters were measured by automatic blood cell counter. The liver function parameters were measured by automatic biochemical analyzer, the hepatitis B virus loads were measured by quantitative PCR analyzer and the results were analyzed by covariance analysis.

RESULTS

In the ALT normal chronic hepatitis B patients group, the viral load had minor effects on the red blood cell parameters.But in the ALT abnormal chronic hepatitis B patients group, the viral load had a significant effect on the red blood cell parameters, and the effect was most manifest in the ALT≥ double upper limit of normal group. The specific performance was that with the viral load increasing, the red blood cell [low copies group (4.10±0.67)×10(12)/L,medium copies group (3.92±0.69)×10(12)/L,high copies group (3.54±0.90) ×10(12)/L], the hemoglobin[low copies group (129.66±21.12 ) g/L, medium copies group (126.23±23.38) g/L, high copies group (112.98±27.77) g/L], the hematocrit (low copies group 37.66±5.68, medium copies group 37.03±6.03, high copies group 33.34±8.15) decreased(P=0.006,0.007,0.010),the mean corpuscular volume [low copies group (92.17±6.53) fL, medium copies group (94.85±7.95) fL, high copies group (101.63±11.33) fL], the mean corpuscular hemoglobin [low copies group (31.70±2.22) pg, medium copies group (33.11±3.62) pg, high copies group (34.65±3.13) pg], the mean corpuscular hemoglobin concentration [low copies group (344.28±17.17) g/L, medium copies group (351.33±16.90) g/L, high copies group (358.12±15.67) g/L], and the red blood cell distribution width-standard deviation [low copies group (52.49±9.04) fL, medium copies group (56.96±7.19) fL, high copies group (61.23 ±7.23) fL] increased(P=0.000,0.000,0.002,0.000).

CONCLUSION

Observing the effect of the viral load on the red blood cell parameters in chronic hepatitis B patients can reflect the effect of hepatitis B virus on the immune response and liver function in the different pathological stages, providing theoretical support for the clinical antiviral treatment.

Changes of pituitary and penile structure in male adult rats following castration and high-fat diet

AIM

To investigate the influence of low androgen levels and high-fat diet on the structure of pituitary and penis in male rats.

METHODS

Ten-week-old adult male Sprague-Dawley rats were randomly divided into 2 groups, one fed a high-fat diet the other fed a normal diet; each group consisted of 3 subgroups: controls, castrated rats (with low androgen), and castrated rats given undecanoate replenishment. After 11 weeks, the structure of pituitary and penis were observed under light microscopy. Immunohistochemistry was used to assess the expression of FSH in pituitary and cyclooxygenase-2 (COX-2) in corpora cavernosa penis.

RESULTS

The structures of pituitary and penis in castrated rats were injured, and were more damaged in castration together with high-fat diet. Immunohistochemistry showed FSH expression in castrated rats pituitary while castrated rats on a high-fat diet had less positive staining than those on a normal diet. Vascular structure of corpora cavernosa penis, showed a strongly positive COX-2 expression in high-fat diet rats.

CONCLUSIONS

Castration and high-fat diet could induce structural damages of pituitary and penis in male rats. Replacement with testosterone could partially restore the impaired structure. The positive expression of COX-2 implied inflammatory pathway existence on vascular structure of penis in high-fat diet and low-androgen male rats.

Gamma Knife irradiation–induced histopathological changes in the trigeminal nerves of rhesus monkeys

Object

The authors' goal was to observe histopathological changes in the trigeminal nerve after Gamma Knife surgery (GKS) in rhesus monkeys, and to investigate the radiobiological mechanism of GKS for primary trigeminal neuralgia. The nerve length–dosage effect of irradiation is also discussed.

Methods

One of 5 rhesus monkeys randomly served as a control, and the other 4 monkeys were randomly administered a target radiation dose of 60, 70, 80, or 100 Gy (a different dose in each animal). The size of the collimator was 4 mm, and the target point was the trigeminal nerve root. In each experimental monkey, one side was exposed to single-target-point irradiation, and the contralateral side was exposed to double-target-point irradiation. After 6 months, the trigeminal nerve root was examined using light microscopy, transmission electron microscopy, and immunohistochemistry.

Results

At each radiation dose, the damage to the nerve tissue by single-target-point irradiation was identical to that caused by double-target-point irradiation. In the trigeminal nerve tissues of the monkeys irradiated with 60 and 70 Gy, there was limited nerve demyelination and degeneration, fragmentation, or loss of axons. In the trigeminal nerve tissue of the monkey irradiated with 80 Gy, the nerve tissue showed a disordered structure. In the trigeminal nerve tissue of the monkey irradiated with 100 Gy, there was severe derangement in the structure of the nerve tissue, and extensive demyelination, fragmentation, and loss of axons.

Conclusions

The target doses of 60 and 70 Gy have very little impact on the structure of the trigeminal nerve. Irradiation at 80 Gy can cause partial degeneration and loss of axons and demyelination. A 100-Gy dose can cause some necrosis of neurons. Comparing the single-target-point with the double-target-point irradiation, the extent of damage to the nerve tissue is identical, and no difference in the nerve length–dosage effect was found.

Effect of Inhibition of the Central Nucleus of the Amygdala and Drug Experience on the Regions Underlying Footshock-Induced Reinstatement of Morphine Seeking

This study assessed the effect of inhibition of the central nucleus of the amygdala (CeA) and drug experience on brain regions underlying footshock-induced reinstatement of morphine-seeking behaviour in rats. The difference in time spent in two chambers of a place-preference apparatus was used to measure morphine-conditioned place preference. Fos was measured as a marker of neuronal activation in the ventral bed nucleus of the stria terminalis (BNSTv) and ventral tegmental area (VTA). Footshock was found to enhance Fos expression in the BNSTv regardless of drug experience. In the VTA, morphine and footshock had an interactive effect on the increase in Fos expression. Inhibition of the CeA decreased Fos expression in the BNSTv regardless of drug experience, whereas in the VTA this effect only occurred in morphine-treated rats. These results suggest that drug experience has no differential effect on the BNSTv however morphine produces footshock sensitization in the VTA. CeA inhibition modulates the footshock-induced activity of these regions of the brain and attenuates reinstatement of drug seeking behaviour.

Modeling fire-induced smoke spread and carbon monoxide transportation in a long channel: Fire Dynamics Simulator comparisons with measured data

Smoke and toxic gases, such as carbon monoxide, are the most fatal factors in fires. This paper models fire-induced smoke spread and carbon monoxide transportation in an 88m long channel by Fire Dynamics Simulator (FDS) with large eddy simulation (LES). FDS is now a well-founded fire dynamics computational fluid dynamic (CFD) program, which was developed by National Institute of Standards and Technology (NIST). Two full scale experiments with fire sizes of 0.75 and 1.6MW were conducted in this channel to validate the program. The spread of the fire-induced smoke flow together with the smoke temperature distribution along the channel, and the carbon monoxide concentration at an assigned position were measured. The FDS simulation results were compared with experimental data with fairly good agreement demonstrated. The validation work is then extended to numerically study the carbon monoxide concentration distribution, both vertically and longitudinally, in this long channel. Results showed that carbon monoxide concentration increase linearly with the height above the floor and decreases exponentially with the distance away from the fire source.

Ancient paddy soils from the Neolithic age in China’s Yangtze River Delta

Identifying prehistoric irrigated rice fields and characterizing the beginning of paddy soil development are important for a better understanding of human development and agricultural history. In 2003, paddy soils and irrigated rice fields buried at a depth of 100-130 cm were excavated at Chuo-dun-shan in the Yangtze River Delta, close to Suzhou, China. The fields of sizes between 1.4 and 16 m(2) were surrounded with ridges that were connected to ditches/ponds via outlets to control the water level within the fields. Many carbonized and partly carbonized rice grains with an age of 3,903 B.C. (measured (14)C age 5,129+/-45 a BP) were recovered. The surface layers of these buried paddy fields showed a high content of soil organic matter and a considerable high density of rice opals. The latter were identified to derive from Oryza spp. Solid-state (13)C nuclear magnetic resonance spectroscopy revealed aromatic carbon (C) as the predominant organic C form in the fossil surface layer. This is expected, if the major source represents burnt rice and straw. In summary, our data are in agreement with new evidences indicating that in China, paddy soils and irrigated rice cultivation were initiated and developed more than 6,000 years ago.

Nitrogen and phosphorus cycling in shrimp ponds and the measures for sustainable management

Six ponds of age 3 were selected 45 km north from Suzhou in the Tailake region, and research conducted on nitrogen and phosphorus cycling in P. vannanmei (Penaeus vannanme) ponds and M. nipponense (Macrobrachium nipponense) hatchery ponds under normal management. Two treatments each had three replications. The results confirmed that feed was the major path of nitrogen and phosphorus input, each accounted for 61.24% (193.81 kg ha(-1)) and 81.08% (45.20 kg ha(-1)) of the total nitrogen and phosphorus input for P. vannanme ponds; the values for M. nipponense ponds were 43.93% (86.31 kg ha(-1)) and 57.67% (14.61 kg ha(-1)), respectively. Water pumped into ponds contributed on average 83.57 kg ha(-1) nitrogen and 8.48 kg ha(-1) phosphorus for P. vannanmei ponds, and 87.48 kg ha(-1) nitrogen and 7.00 kg ha(-1) phosphorus for M. nipponense hatchery ponds. Shrimp harvest recovered 102.81 kg ha(-1) nitrogen (32.94% of the total nitrogen input) and 7.94 kg ha(-1) phosphorus (14.23% of the total phosphorus input) for P. vannanme ponds; and 43.94 kg ha(-1) nitrogen and 4.46 kg ha(-1) phosphorus for M. nipponense hatchery ponds. The sum of nitrogen losses through volatilization, denitrification and sedimentation was 173.62 and 122.39 kg ha(-1), 54.86% and 62.29% of the total nitrogen input for P. vannanme ponds and M. nipponense hatchery ponds, respectively. Sediment accumulated 41.46 and 14.63 kg ha(-1) phosphorus, 74.37% and 64.85% of the total phosphorus input for P. vannanm ponds and M. nipponense hatchery ponds. Draining and seeping caused 40.06 kg ha(-1) nitrogen (12.66% of total nitrogen input) and 6.36 kg ha(-1) phosphorus (11.40% of total phosphorus input) loss to the surrounding water from P. vannanme ponds in 114 days; 30.14 kg ha(-1) nitrogen (15.34% of the total input) and 4.45 kg ha(-1) phosphorus (17.57% of the total input) to channel water from M. nipponense hatchery ponds in 87 days, respectively. Countermeasures for sustainable pond management include improving feeds and feeding, sediment treatments, machine aerating, chemicals with no pollution, and integrated fish-shrimp cultivation. Management of water resources for pond and methods to reduce nitrogen and phosphorus loading into surrounding water from drainage are elucidated.

The adsorption of lead and copper from aqueous solution on modified peat-resin particles

Raw peat was modified with sulfuric acid, then mixed modified with resin to prepare the modified peat-resin particles. Using the batch experimental systems, the removal of heavy metals (copper and lead) on the modified peat-resin particles was investigated. The data of the adsorption isotherm could be fitted by the Langmuir equation well. The adsorption rate of heavy metals on modified peat-resin particles was very swift. The removal processes of heavy metals on modified peat-resin particles could be well described by pseudo-second order model. The adsorption rate of lead was affected by the initial heavy metal concentration, initial pH, particle size, agitation speed and particle mass. In the adsorption of heavy metals (lead and copper) on the modified peat-resin particles, ion exchange was the major reaction mechanism. Desorption data showed that the lead adsorbed by modified peat-resin particle could be desorbed by 0.5 N or 1.0 N HNO3. The desorption rate was swift. The experiments indicated that the modified peat-resin particles have great potential for the removal of heavy metals from wastewater.

Levels of urinary inter-alpha-trypsin inhibitor trimer as a function of age and sex-hormone status in males and females not forming stones

OBJECTIVES

To determine if levels of inter-alpha-trypsin inhibitor (I alpha TI)-trimer differ in normal individuals based on age, gender or hormonal status, as the regulation of calcium oxalate (CaOx) crystallization inhibitors, e.g. by sex steroids, could be a mechanism contributing to the differences in CaOx urolithiasis between the sexes.

SUBJECTS AND METHODS

Voided urine samples were collected from normal males and females. In Experiment 1 samples were grouped by gender and age, i.e. paediatric (PED) < or = 10 years, male (M) 21, female (F) 14; young adult (YGAD) 20-30 years, M 23, F 18; adults (AD), 35-50 year, M 25, F 13; adults aged > or = 60 years (> 60), M 24, F 16 (totals, M 93, F 61). In Experiment 2 samples were grouped by gender, age and hormonal status, i.e. PED, M 24, F 17; AD, M 24, F 22; > 60 and not on hormonal therapy, M 23, F 30; M > 60 and on androgen deprivation therapy (ANDEP) 18; and F > 60 on oestrogen supplementation, F+EST, 18 (total M 89, F 85). Levels of urinary I alpha TI-trimer were determined by immunoblotting and enhanced chemiluminescence, and relative densities of the bands determined.

RESULTS

In both experiments the relative levels of I alpha TI-trimer were 2-7 times higher in M-PED than in all other groups of males (P < or = 0.007). Among adult males, I alpha TI-trimer levels were similar in all groups, including ANDEP (P > or = 0.9). There were no differences in the relative levels of I alpha TI-trimer among any of the groups of females, regardless of age or hormonal status (P > or = 0.7).

CONCLUSIONS

In males a decrease in I alpha TI-trimer was associated with the onset of adulthood and entry into the 'stone-forming years'. Females did not show this decrease, and neither sex showed an increase in I alpha TI-trimer in the > 60 group, when the incidence of CaOx urolithiasis is supposedly declining. While changes in urinary I alpha TI-trimer levels in males may reflect maturational changes in the kidney, overall these data do not support the hypothesis that the age-related changes in the incidence of urolithiasis are paralleled by changes in the expression I alpha TI-trimer. Additionally, the sex steroids do not appear to acutely regulate the expression of I alpha TI-trimer in adults, making differences in I alpha TI-trimer levels unlikely to be the reason for the disparity in the incidence of CaOx urolithiasis between the sexes.

Serum cytokine levels are altered in patients with West syndrome

The objective of this study is to explore the neuroimmunomodulator effect of interleukin (IL)-2, tumor necrosis factor (TNF)-alpha and interferon (IFN)-alpha in West syndrome (WS). Twenty-three cases of WS (13 males and 10 females, aged 4-14 months old) who first visited and consisted from 10 cryptogenic and 13 symptomatic, were enrolled in this study. Double-antibody sandwich enzyme-linked immunosorbent assay was used to measure serum IL-2, TNF-alpha and IFN-alpha levels in 23 patients with WS and the data were compared to those of 15 healthy infants who were matched with regard to age and sex. Levels of all three cytokines were significantly higher in both cryptogenic and symptomatic WS groups than the control group. Serum IL-2 levels in symptomatic WS were significantly higher than that in cryptogenic WS. There was a positive correlation between IL-2 and TNF-alpha in both cryptogenic and symptomatic WS groups. The immune systems of patients with WS are in an activated state. An imbalance in cytokine levels may be involved in the immunopathology of WS.

Devazepide reversed effect of sincalide against morphine on rat jejunal activities

AIM

To study the antagonism of sincalide to the effect of morphine and its mechanism.

METHODS

The electrophysiologic and mechanic activities of rat jejunum in vitro were recorded.

RESULTS

Acetylcholine (ACh, 150 nmol.L-1) increased the spike potential amplitude (SPA) and the number (SPN) of rat jejunum in vitro, followed by an increase of jejunal contraction amplitudes (CA), showing a positive correlation. Morphine 330 nmol.L-1 inhibited the potentiation of ACh, showing a negative correlation. Sincalide 0.7 nmol.L-1 antagonized the effects of morphine, i.e., the SPA and SPN were increased again, followed by an increase of CA. CCK-A receptor antagonist devazepide (10 nmol.L-1) reversed the antagonism of sincalide to the effect of morphine.

CONCLUSION

Sincalide antagonized the effect of morphine which inhibited the potentiation of ACh on jejunal activities in vitro. The antagonistic effect of sincalide on morphine was mainly mediated by CCK-A receptor.

Effect of devazepide reversed antagonism of CCK-8 against morphine on electrical and mechanical activities of rat duodenum in vitro

AIM: To study the antagonism of cholecystokinin octapeptide (CCK-8) against the effect of morphine and its mechanism.

METHODS: The method and mechanical activities of rat duodenum in vitro were recorded simultaneously.

RESULTS: Acetylcholine (ACh) could increase the amplitude and the number of the spike potential (SPA and SPN) of rat duodenum in vitro, followed by the increase of the duodenal contraction amplitudes (CA), showing a positive correlation. Morphine, on the contrary, inhibited the potentiation of ACh, showing a negative correlation. CCK-8 could antagonize the effects of morphine, i.e. the SPA and SPN were increased again, followed by the increase of CA. CCK-A receptor antagonist Devazepide could reverse the antagonism of CCK-8 to the effect of morphine.

CONCLUSION: CCK-8 could antagonize the effect of morphine which inhibited the potentiation of ACh on the duodenal activities in vitro. The antagonistic effect of CCK-8 on morphine was mainly mediated by CCK-A receptor.

[The effect of RU486 on contractility of rabbit oviduct smooth muscle]

An investigation on the effect of RU486 on isolated ovicluct smooth muscle contraction of pseudopregant rabbits was carried out by using the mechanical-electrical transducer of Galson recorder. The results showed that: (1) RU486 acted directly on the oviduct smooth muscle by increasing contractile frequency, without changing tension and amplitude. This effect is similar to that found in the in vivo experiment. (2) RU486 partially inhibited Ca(2+)-induced smooth muscle contraction and also showed significant synergistic effect of Verapamil and antagonistic effect of NE on muscle contractility. However, RU486 is unable to exert any effect on Forskolin-stimulated contraction. Thus it appears that the RU486 effect on oviduct smooth muscle contraction is a result of affecting intracellular free calium, due possibly to interference of Ca2+ influx and/or endoplasmic reticulum Ca2+ release and Ca(2+)-Ip3 transducing mechanism.

[Anti-arrhythmia and anti-lipid peroxidation effects of methylflavonolamine]

Effects of methylflavonolamine (MFA) on arrhythmias induced by myocardial reperfusion were studied with rat hearts in situ and in vitro. In pentobarbital-anesthetized rats, MFA (20 mg.kg-1, i.v.) pretreatment reduced the incidence of reperfusion-induced ventricular fibrillation after left descending coronary artery ligation (15 min) and reperfusion (3 min) (28.6% vs 85.7% in control, P less than 0.05). Malondialdehyde (MDA) production (85 +/- 9 nmol/g wet wt) was inhibited in myocardium from the reperfused area in comparison with control (133 +/- 15 nmol/g wet wt). In isolated rat hearts with local ischemia (15 min) and reperfusion (1 min), MFA 5 mumol.L-1 (perfused 10 min prior to coronary artery ligation) prevented reperfusion-induced arrhythmias (0% vs 85.7% in control, P less than 0.01). In myocardium from the reperfused area, superoxide dismutase (SOD) and catalase (Cat) activity was increased and xanthine oxidase (XOD) activity, MDA production and nonesterified fatty acids (NEFA) contents were decreased. The results show that MFA prevents reperfusion-induced arrhythmia by inhibiting lipid peroxidation and regulating the metabolism of NEFA.

Simultaneous electric activities of pain-excitation and pain-inhibition neurons in nucleus parafascicularis of thalamus in rats during acute morphine tolerance

When acute morphine-tolerated rat was administered by ip morphine (10 mg/kg) which was effective before the acute tolerance to morphine, both the inhibitory effect of morphine on the electric discharges of pain-excitation neurons (PEN) in nucleus parafascicularis (PF) and the excitatory effect of morphine on the electric activities of pain-inhibition neurons (PIN) were simultaneously weakened, or even vanished. If a large dose of morphine (20 mg) was given ip, the modulating action of morphine on simultaneous electric discharges of PEN and PIN reappeared. It is obvious that the phenomenon of acute morphine tolerance and the antagonism to morphine tolerance can be explicitly expressed on the level of central neurons.