Abnormal amplitude of low-frequency fluctuations associated with sleep efficiency in major depressive disorder

BACKGROUND

Sleep disturbance is one of the most frequent somatic symptoms in major depressive disorder (MDD), but the neural mechanisms behind it are not well understood. Sleep efficiency (SE) is a good indicator of early awakening and difficulty falling asleep in MDD patients. Our study aimed to investigate the relationship between sleep efficiency and brain function in MDD patients.

METHODS

We recruited 131 MDD patients from the Fourth People's Hospital in Hefei, and 71 well-matched healthy controls who were enrolled from the community. All subjects underwent resting-state functional MRI. Brain function was measured using the fractional amplitude of low-frequency fluctuation (fALFF), sleep efficiency was objectively measured by polysomnography (PSG), and clinical scales were used to evaluate depressive symptoms and sleep status. Multivariate regression analysis was performed to assess the relationship between the amplitude of the low frequency fluctuation fraction and sleep efficiency.

RESULT

Three brain regions with relevance to sleep efficiency in MDD patients were found: inferior occipital gyrus (Number of voxels = 25, peak MNI coordinate x/y/z = -42/-81/-6, Peak intensity = 4.3148), middle occipital gyrus (Number of voxels = 55, peak MNI coordinate x/y/z = -30/-78/18, Peak intensity = 5.111), and postcentral gyrus (Number of voxels = 26, peak MNI coordinate x/y/z = -27/-33/60, Peak intensity = 4.1263). But there was no significant relationship between fALFF and SE in the healthy controls.

CONCLUSION

The reduced sleep efficiency in MDD may be related to their lower neural activity in the inferior occipital gyrus, middle occipital gyrus, and postcentral gyrus. The findings may provide a potential neuroimaging basis for the clinical intervention in patients with major depressive disorder with sleep disturbances.

Association between exposure to outdoor artificial light at night during pregnancy and glucose homeostasis: A prospective cohort study

BACKGROUND

Outdoor artificial light at night (ALAN) has been linked to an elevated risk of diabetes, but the available literature on the relationships between ALAN and glucose homeostasis in pregnancy is limited.

METHODS

A prospective cohort study of 6730 pregnant women was conducted in Hefei, China. Outdoor ALAN exposure was estimated using satellite data with individual addresses at a spatial resolution of approximately 1 km, and the average ALAN intensity was calculated. Gestational diabetes mellitus (GDM) was diagnosed based on a standard 75-g oral glucose tolerance test. Multivariable linear regression and logistic regression were used to estimate the relationships between ALAN and glucose homeostasis.

RESULTS

Outdoor ALAN was associated with elevated glucose homeostasis markers in the first trimester, but not GDM risk. An increase in the interquartile range of outdoor ALAN values was related to a 0.02 (95% confidence interval [CI]: 0.00, 0.03) mmol/L higher fasting plasma glucose, a 0.42 (95% CI: 0.30, 0.54) μU/mL increase in insulin and a 0.09 (95% CI: 0.07, 0.12) increase in homeostatic model assessment of insulin resistance (HOMA-IR) during the first trimester. Subgroup analyses showed that the associations between outdoor ALAN exposure and fasting plasma glucose, insulin, and HOMA-IR were more pronounced among pregnant women who conceived in summer and autumn.

CONCLUSIONS

The results provided evidence that brighter outdoor ALAN in the first trimester was related to elevated glucose intolerance in pregnancy, especially in pregnant women conceived in summer and autumn, and effective strategies are needed to prevent and manage light pollution.

[Preliminary clinical application of novel magnetic navigation and ultrasound-guided percutaneous transhepatic cholangiography drainage through the right liver duct for malignant obstructive jaundice]

Objective: To analyze the clinical application value of a novel magnetic navigation ultrasound (MNU) combined with digital subtraction angiography (DSA) dual-guided percutaneous transhepatic biliary drainage (PTCD) through the right hepatic duct for the treatment of malignant obstructive jaundice. Methods: Randomized controlled trial. The clinical data of 64 patients with malignant obstructive jaundice requiring PTCD through the right hepatic duct at the Hepatobiliary Center of the First Affiliated Hospital of Nanjing Medical University (Jiangsu Province People's Hospital) from December 2018 to December 2021 were retrospectively analyzed. The MNU group (n=32) underwent puncture guided by a novel domestic MNU combined with DSA, and the control group (n=32) underwent puncture guided by traditional DSA. The operation time, number of punctures, X-ray dose after biliary stenting as shown by DSA, patients' tolerance of the operation, success rate of the operation, pre- and post-operative total bilirubin, and incidence of postoperative complications were compared between the two groups. Results: The operation time of the MNU group was significantly shorter than that of the control group [(17.8±7.3) vs. (31.6±9.9) min, t=-6.35,P=0.001]; the number of punctures in the MNU group was significantly lower [(1.7±0.6) vs. (6.3±3.9) times, t=-6.59, P=0.001]; and the X-ray dose after biliary stenting as shown by DSA in the MNU group was lower than that in the control group [(132±88) vs. (746±187) mGy, t=-16.81,P<0.001]; Five patients in the control group were unable to tolerate the operation, and two stopped the operation, however all patients in the MNU group could tolerate the operation, and all completed the operation, with a success rate of 100% (32/32) in the MNU group compared to 93.8%(30/32) in the control group; the common complications of PTCD were biliary bleeding and infection, and the incidence of biliary bleeding (25.0%, 8/32) and infection (18.8%, 6/32) in the MNU group was significantly lower than that in the control group, 53.1% (17/32) and 28.1% (9/32), respectively. Conclusion: Magnetic navigation ultrasound combined with DSA dual-guided PTCD through the right biliary system for the treatment of malignant obstructive jaundice is safe and feasible.

Neural substrates underlying REM sleep duration in patients with major depressive disorder: A longitudinal study combining multimodal MRI data

INTRODUCTION

Prior studies have discussed rapid eye movement (REM) sleep disturbance as a potential endophenotype of major depressive disorder (MDD). However, the neural substrates underlying the percentage of REM sleep duration (REM%) and its association with disease progression in MDD remain unclear.

METHODS

One hundred and fourteen MDD patients and 74 healthy controls (HCs) underwent resting-state functional and perfusion magnetic resonance imaging (MRI) scans as well as overnight polysomnography examination to assess brain function and REM%, with 48 patients completing follow-up visits. Correlation and mediation analyses were conducted to investigate the associations among baseline REM%, multimodal brain imaging measures, and the improvement of depressive symptoms at follow-up in MDD.

RESULTS

We found voxel-wise correlations between baseline REM% and multimodal brain imaging metrics in many brain regions involved in sensorimotor, visual processing, emotion, and cognition in patients with MDD. Moreover, the baseline REM% was correlated with the improvement of depressive symptoms from acute to remitted status in patients through regulating brain activity in the left inferior temporal gyrus and cerebral blood flow in the bilateral paracentral lobule.

CONCLUSION

Our findings help to identify the neural underpinnings of REM% in depression and highlight REM% as a potential prognostic biomarker to predict disease progression. These may inform future novel interventions of MDD from the perspective of regulating REM sleep.

Association between ambient particulate matters and anhedonia among patients with depression

Recent studies have linked ambient air pollution to depression. Anhedonia is a core symptom of depression which severely impacts on prognosis. The present study aims to investigate the association of PM2.5 and PM10 exposure with anhedonia in depressed patients. A total of 538 patients with depression who were hospitalized at the Fourth People's Hospital of Hefei between June 2017 and December 2021 were included. We estimated ambient particulate matters exposure, including PM2.5 and PM10, using a satellite-based spatiotemporal model at a resolution of 1 km2. The revised Physical Anhedonia Scale (RPAS) and the revised Social Anhedonia Scale (RSAS) were evaluated. The association of ambient particulate matters and anhedonia was examined using multiple linear regression models, adjusted for potential confounders. We observed that exposure to PM2.5 were significantly associated with increased RSAS score and RPAS score, with the major effect in the 12-month exposure window (β = 1.238; 95%CI, 0.353, 2.123) and 18-month exposure window (β = 1.888; 95%CI, 0.699, 3.078), respectively. Meanwhile, PM10 levels were also significantly associated with increased RSAS score and RPAS score, with the major effect in the 18-month exposure window (β = 1.220; 95%CI, 0.439, 2) and 3-month exposure window (β = 1.602; 95%CI, 0.062, 3.143), respectively. Subgroup analysis showed that both PM2.5 and PM10 were significantly associated with anhedonia in females, patients < 40 years old, low family income group, and those who had a higher educational level. Our study suggests that long-term PM2.5 and PM10 exposure are associated with more severe anhedonia in patients with depression. These associations were different in subgroup by age, gender, family income, and educational level.

Safety and effectiveness of lurasidone in the treatment of Chinese schizophrenia patients: An interim analysis of post-marketing surveillance

BACKGROUND

Schizophrenia is a psychiatric disorder characterized by chronic or recurrent symptoms. Lurasidone was licensed in China in 2019 for the treatment of adult schizophrenia in adults with a maximum dose of 80 mg/d. However, post-market surveillance (PMS) with an adequate sample size is required for further validation of the drug’s safety profile and effectiveness.

AIM

To conduct PMS in real-world clinical settings and evaluate the safety and effectiveness of lurasidone in the Chinese population.

METHODS

A prospective, multicenter, open-label, 12-wk surveillance was conducted in mainland China. All patients with schizophrenia from 10 sites who had begun medication with lurasidone between September 2019 and August 2022 were eligible for enrollment. Safety assessments included adverse events (AEs), adverse drug reactions (ADRs), extrapyramidal symptoms (EPS), akathisia, use of EPS drugs, weight gain, and laboratory values as metabolic parameters and the QTc interval. The effectiveness was assessed using the brief psychiatric rating scale (BPRS) from baseline to the end of treatment.

RESULTS

A total of 965 patients were enrolled in the full analysis set and 894 in the safety set in this interim analysis. The average daily dose was 61.7 ± 19.08 mg (mean ± SD) during the treatment. AEs and ADRs were experienced by 101 patients (11.3%) and 78 patients (8.7%), respectively, which were mostly mild. EPS occurred in 25 individuals with a 2.8% incidence, including akathisia in 20 individuals (2.2%). Moreover, 59 patients received drugs for treating EPS during the treatment, with an incidence of 6.6% which dropped to 5.4% at the end of the treatment. The average weight change was 0.20 ± 2.36 kg (P = 0.01687) with 0.8% of patients showing a weight gain of ≥ 7% at week 12 compared with that at the baseline. The mean values of metabolic parameters and the QTc interval at baseline and week 12 were within normal ranges. The mean changes in total BPRS scores were -8.9 ± 9.76 (n = 959), -13.5 ± 12.29 (n = 959), and -16.8 ± 13.97 (n = 959) after 2/4, 6/8, and 12 wk, respectively (P < 0.001 for each visit compared with the baseline) using the last-observation-carried-forward method.

CONCLUSION

The interim analysis of the PMS of adult patients with schizophrenia demonstrate the safety and effectiveness of lurasidone in the Chinese population. No new safety or efficacy concerns were identified.

Brain function mediates the association between low vitamin D and neurocognitive status in female patients with major depressive disorder

BACKGROUND

Vitamin D is engaged in various neural processes, with low vitamin D linked to depression and cognitive dysfunction. There are gender differences in depression and vitamin D level. However, the relationship between depression, gender, vitamin D, cognition, and brain function has yet to be determined.

METHODS

One hundred and twenty-two patients with major depressive disorder (MDD) and 119 healthy controls underwent resting-state functional MRI and fractional amplitude of low-frequency fluctuations (fALFF) was calculated to assess brain function. Serum concentration of vitamin D (SCVD) and cognition (i.e. prospective memory and sustained attention) were also measured.

RESULTS

We found a significant group-by-gender interaction effect on SCVD whereby MDD patients showed a reduction in SCVD relative to controls in females but not males. Concurrently, there was a female-specific association of SCVD with cognition and MDD-related fALFF alterations in widespread brain regions. Remarkably, MDD- and SCVD-related fALFF changes mediated the relation between SCVD and cognition in females.

CONCLUSION

Apart from providing insights into the neural mechanisms by which low vitamin D contributes to cognitive impairment in MDD in a gender-dependent manner, these findings might have clinical implications for assignment of female patients with MDD and cognitive dysfunction to adjuvant vitamin D supplementation therapy, which may ultimately advance a precision approach to personalized antidepressant choice.

The reduction of vitamin D in females with major depressive disorder is associated with worse cognition mediated by abnormal brain functional connectivity

Low vitamin D is linked to major depressive disorder (MDD) through affecting the brain. Gender difference is apparent in MDD and vitamin D level. We aimed to examine the association between gender, vitamin D, clinical presentations, and brain functional connectivity in a large cohort of MDD patients and comparison subjects. Resting-state functional MRI data from 122 patients and 119 controls were collected to perform a combined analysis of functional connectivity density (FCD) and seed-based functional connectivity (FC). Peripheral venous blood samples were obtained to measure serum concentration of vitamin D (SCVD). Clinical presentations (symptoms profiles and cognition) were also assessed. We found an interaction of group and gender on SCVD in which MDD patients demonstrated lower SCVD than controls in females rather than males. Concurrently, lower SCVD was associated with worse cognitive performance (prospective memory and sustained attention). Compared with controls, female MDD patients showed reduced FCD and FC of the left middle frontal gyrus, which were related to lower SCVD. Importantly, these FCD and FC changes mediated the relationship between lower SCVD and cognitive dysfunction. Our findings suggest that functional connectivity abnormalities may serve as neural substrates underlying the associations between low vitamin D and cognitive impairments in female MDD patients, providing unique insight into treatment and prevention of MDD and its related cognitive dysfunction from the perspective of regulating circulating vitamin D.

Neural mechanism of the relationship between sleep efficiency and clinical improvement in major depressive disorder: A longitudinal functional magnetic resonance imaging study

BACKGROUND

Antidepressants represent the most common treatment of choice for major depressive disorder (MDD). In this study, we aimed to explore the status-related changes (acute vs. remitted status) in brain function in patients with MDD.

METHODS

Regular antidepressant medications (an average of 7 months after the initial visit, remitted status) were received by 48 patients with MDD. All the patients underwent MRI and polysomnography examinations as well as clinical assessment at each visit.

RESULTS

We found that baseline fractional amplitude of low-frequency fluctuations (fALFF) of right superior parietal gyrus (SPG) and middle frontal gyrus could predict depression and anxiety symptoms improvement from acute to remitted status in patients with MDD, respectively. Moreover, we found a significant positive correlation between the fALFF of right SPG and baseline sleep efficiency (SE) in patients with MDD. Further mediation analysis revealed that the fALFF of right SPG mediated the relationship between baseline SE and depressive symptom improvement.

CONCLUSION

Apart from highlighting the fALFF as a potential prognostic indicator to predict and track disease progression in patients with MDD, these findings might provide a neural mechanism basis for improving sleep quality of patients with MDD and thus promoting the recovery of clinical symptoms, as well as provide a practical basis for clinical interventions in patients with MDD with sleep disorders.

Functional stability predicts depressive and cognitive improvement in major depressive disorder: A longitudinal functional MRI study

Functional stability is a newly developed dynamic functional connectivity approach. The objective of this study was to adopt functional stability to investigate diagnosis-associated abnormalities (patients vs. controls) and status-related changes (acute vs. remitted status) in brain function in major depressive disorder (MDD). 132 MDD patients and 102 healthy controls underwent resting-state functional MRI as well as clinical and cognitive assessment at baseline, with 48 patients completing follow-up examinations at an average of 7 months. Results showed no group differences in baseline functional stability and no longitudinal functional stability changes from acute to remitted status in patients. However, we found that baseline functional stability in the dorsal and ventral anterior cingulate cortex, calcarine sulcus, and middle occipital gyrus could predict improvement in depressive symptoms from acute to remitted status in MDD patients, with longitudinal functional stability changes in these regions related to the degree of symptom improvement. In addition, lower baseline functional stability in the inferior temporal gyrus could predict a greater improvement in sustained attention, which was associated with a greater functional stability increase in this region. Our findings highlight functional stability as a potential prognostic biomarker to predict and track disease progression or stratify MDD patients for optimizing disease management and treatment strategies.

The role of neonatal vitamin D in the association of prenatal depression with toddlers ADHD symptoms: A birth cohort study

BACKGROUND

Vitamin D has been demonstrated a "neuroprotective" effect, but it is unclear whether early-life adequate vitamin D protect adverse neurodevelopment. We aimed to examine the role of neonatal vitamin D in the association of maternal depression (MD) symptoms with toddlers ADHD.

METHODS

Participants included 1 125 mother-infant pairs from the China-Anhui Birth Cohort study. MD was assessed by the Center for Epidemiological Studies Depression Scale (CES-D) at 30-34 gestational weeks. Toddlers ADHD was reported by the Conners' Hyperactivity Index (CHI) at 48-54 months postpartum. Multiple logistic regression models were performed to evaluate the association of maternal depressive score and toddlers ADHD while cord blood 25(OH)D levels were stratified.

RESULTS

Toddlers of mothers with higher depression score were at higher risk of ADHD (20.1% vs 11.1%, P = 0.003; adjusted RR=1.75, 95% CI: 1.10-2.81). Among toddlers with neonatal vitamin D deficiency (VDD), ADHD risk was significantly increased with maternal MD (adjusted RR=3.74, 95% CI: 1.49-9.41), but the association was not found in toddlers with neonatal vitamin D adequacy (VDA). Compared to toddlers without MD, toddlers with both MD and neonatal VDD had higher risk of ADHD (adjusted RR=3.10, 95% CI: 1.44-6.63). But the risk did not significantly increase in toddlers with MD and neonatal VDA (adjusted RR=1.53, 95% CI: 0.86-2.72).

LIMITATIONS

Maternal depressive symptoms in early pregnancy and anxious symptoms were needed to include.

CONCLUSION

This prospective study indicated that the detrimental effect of maternal prenatal depressive symptoms on offspring's ADHD symptoms strengthened in toddlers with neonatal VDD.

Neural correlates of the association between depression and high density lipoprotein cholesterol change

There is evidence that major depressive disorder (MDD) is related to serum lipid level alterations. However, the neural correlates underlying this association remain poorly understood. Forty-nine patients with MDD and fifty healthy controls (HCs) underwent structural, resting-state functional and diffusion magnetic resonance imaging scans. Voxel-based morphometry, functional connectivity (FC) and tract-based spatial statistics analyses were performed to assess brain structure and function, respectively. Blood samples were collected to measure serum levels of lipid variables including total cholesterol, triglyceride and high density lipoprotein cholesterol (HDL-C). Correlation and mediation analyses were conducted to investigate the associations of serum lipid levels with brain imaging measures in MDD patients and HCs, respectively. We found that the serum HDL-C level in MDD patients was lower than that in HCs. The lower serum HDL-C level was associated with lower gray matter volume (GMV) in ventromedial prefrontal cortex (VMPFC), higher within-network FC of the default mode network, and lower micro-structural integrity in multiple white matter regions in MDD patients. Moreover, the within-default mode network FC mediated the relationship between GMV in VMPFC and serum HDL-C level; white matter integrity in genu of corpus callosum mediated the relationship between serum HDL-C level and depressive symptom severity. However, we did not observe any correlations between serum lipids and brain imaging parameters in HCs. These findings help to identify neural correlates underlying the association between depression and serum HDL-C change, which may provide new insight into intervention, treatment and prevention of depression from the perspective of regulating serum lipids.

Vitamin D supplementation improves anxiety but not depression symptoms in patients with vitamin D deficiency

OBJECTIVE

Epidemiological evidence indicated a relationship between vitamin D (VD) and depression with anxiety, but their therapeutic relationship has not been fully elucidated. This study aimed to examine whether VD supplementation would relieve symptoms in patients with depression and anxiety with low serum 25-hydroxy VD [25(OH) D] levels.

METHOD

Participants with low 25(OH)D levels were randomized to control or daily VD group and were followed up for 6 months. Serum concentrations of 25(OH) D were measured using commercial kits. Psychological symptoms were evaluated with the Hamilton Depression Rating Scale-17 (HAMD-17), Revised Social Anhedonia Scale (RSAS), Revised Physical Anhedonia scale (RPAS), and Hamilton Anxiety Rating Scale-14 (HAMA-14). The trial was listed in the trial registration (http://www.medresman.org.cn/uc/index.aspx; NTR number: ChiCTR2000030130).

RESULTS

In this clinical population, no significant difference in depression symptoms was detected between VD group and control group at both baseline and at the endpoint of our study. The HAMD-17, RSAS, and RPAS scores did not change significantly between VD and control groups from baseline to endpoint (all p > .05). However, there was a significant difference in time effect of the total HAMA-14 scores between the two groups (β [95% Cl] = -2.235 [-3.818, -0.653], p = .006).

CONCLUSIONS

Vitamin D supplementation could improve the anxiety symptoms but not depressive symptoms in depressive patients with low VD level after the 6-month intervention.

Vitamin D status affects the relationship between lipid profile and high-sensitivity C-reactive protein

Background

The biological pathways through which vitamin D is involved in the regulation of systemic inflammation remain largely unknown.

Objective

The objective of this study was to evaluate the role of vitamin D status on the relationship between lipid profile and high-sensitivity C-reactive protein (hs-CRP) in pregnant women.

Design

Serum 25-hydroxyvitamin D (25(OH)D), hs-CRP, and indicators of lipid profiles (total cholesterol, TC; triglyceride, TG; high-density lipoprotein cholesterol, HDL-C; low-density lipoprotein cholesterol, LDL-C), were measured in 2479 pregnant women during the second trimester. Potential confounding including maternal sociodemographic characteristics, perinatal health status, diet, and lifestyle was prospectively collected. Multiple regression models and cubic models were used to evaluate the associations.

Results

There was a significant non-linear relationship between lipid profile (TC, TG, HDL-C, LDL-C) and hs-CRP (P < 0.05). Increased serum 25(OH)D was significantly associated with decreasing TC, TG, HDL-C, LDL-C, and hs-CRP levels. Compared with medium levels of lipids group, pregnant women with higher levels of TC or TG have higher levels of hs-CRP, and pregnant women with lower levels of TC, HDL-C or LDL-C also have higher levels of hs-CRP in the vitamin D deficient group, and there was a significant correlation between low levels of TG and decreased hs-CRP (adjusted β for TG: -0.063, 95%CI: − 0.120,-0.007) in the non-vitamin D deficient group. Mediators that had appreciable shares of the associations between 25(OH)D and hs-CRP was TG (10.2% of the association; β = − 0.011; total indirect effect: 95% CI: − 0.019, − 0.002). The cubic model suggested that a steep increase in the adjusted regression coefficient of lipid with hs-CRP up to 50 nmol/L of 25(OH)D, and the highest adjusted regression coefficients were observed in pregnant women with 25(OH)D above 50 nmol/L.

Conclusion

Our findings suggest that high levels of vitamin D during pregnancy may improve lipid profile levels and inhibit elevated hs-CRP induced by high lipid metabolism.

The relationship between sleep efficiency and clinical symptoms is mediated by brain function in major depressive disorder

BACKGROUND

Sleep disturbance is a common and key symptom that affects most of patients with major depressive disorder (MDD). However, neural substrates underlying sleep disturbance and their clinical relevance in depression remain unclear.

METHODS

Ninety-six MDD patients underwent resting-state functional MRI. Fractional amplitude of low-frequency fluctuation (fALFF) and resting-state functional connectivity (rsFC) were used to measure brain function. Overnight polysomnography was performed to objectively measure sleep efficiency (SE), which was used to classify patients into normal sleep efficiency (NSE) and low sleep efficiency (LSE) groups. Between-group differences in fALFF and rsFC were examined using two-sample t-tests. Moreover, correlation and mediation analyses were conducted to test for potential associations between SE, brain functional changes, and clinical variables.

RESULTS

LSE group showed decreased fALFF in right cuneus, thalamus, and middle temporal gyrus compared to NSE group. MDD patients with low SE also exhibited lower rsFC of right cuneus to right lateral temporal cortex, which was associated with more severe depression and anxiety symptoms. More importantly, mediation analyses revealed that the relationships between SE and severity of depression and anxiety symptoms were significantly mediated by the altered rsFC. In addition, these low SE-related brain functional alterations were not affected by antidepressant medication and were independent of structural changes.

LIMITATIONS

The lack of healthy controls because of "first-night effect".

CONCLUSION

These findings not only may expand existing knowledge about neuropathology of sleep disturbance in depression, but also may inform real-world clinical practice by improving depression and anxiety symptoms through sleep regulation.

Brain Structural and Functional Alterations Specific to Low Sleep Efficiency in Major Depressive Disorder

Background

Sleep disturbance is common in patients with major depressive disorder (MDD), but the exploration of its neural underpinnings is limited by subjective sleep measurement and single-modality neuroimaging analyses.

Methods

Ninety six patients with MDD underwent polysomnography examinations and multi-modal magnetic resonance imaging (MRI) scans. According to sleep efficiency, patients were subdivided into well-matched normal sleep efficiency (NSE, N = 42; 14 men; aged 43 ± 10 years) and low sleep efficiency (LSE, N = 54; 23 men; aged 45 ± 12 years) groups. Inter-group differences in brain structure and function were examined by applying voxel-based morphometry (VBM), regional homogeneity (ReHo) and functional connectivity strength (FCS), and tract-based spatial statistics (TBSS) approaches to structural, functional, and diffusion MRI data, respectively.

Results

There was no significant difference in gray matter volume (GMV) between the NSE and LSE groups. Compared with the NSE group, the LSE group showed increased axial diffusivity in the left superior and posterior corona radiata, and left posterior limb and retrolenticular part of internal capsule. In addition, the LSE group exhibited decreased ReHo in the bilateral lingual gyri and right postcentral gyrus yet increased FCS in the left angular gyrus relative to the NSE group. Moreover, validation analyses revealed that these results remained after adjusting for the medication effect.

Conclusion

Our data indicate that preserved gray matter morphology, impaired white matter integrity, and decreased local synchronization degree yet increased FCS are specific to low SE in MDD patients. These findings of disassociation between structural and functional alterations might provide insights into the neural mechanisms of sleep disturbance in depression.

Selective microstructural integrity impairments of the anterior corpus callosum are associated with cognitive deficits in obstructive sleep apnea

BACKGROUND

There is some evidence that obstructive sleep apnea (OSA) patients have white matter integrity abnormality in the corpus callosum (CC). However, whether the CC subregions are differentially affected in OSA is largely unknown.

METHODS

Twenty patients with OSA and 24 well-matched healthy controls were enrolled and underwent diffusion tensor imaging (DTI) and clinical and cognitive assessments. DTI tractography was used to reconstruct the CC which was divided into five subregions. Intergroup differences in multiple diffusion metrics of each CC subregion and their correlations with clinical and cognitive parameters were tested.

RESULTS

In comparison with healthy controls, OSA patients exhibited white matter integrity alterations in the anterior CC, characterized by increased radial diffusivity (RD) in the subregion 1 and decreased fractional anisotropy (FA) along with increased mean diffusivity (MD) and RD in the subregion 2. Moreover, we found that the lower microstructural integrity in the anterior CC was correlated with worse prospective memory and sustained attention in OSA patients.

CONCLUSIONS

These findings indicate that the selective impairments of the anterior CC may help clarify the neural correlates of cognitive impairments in OSA.

Quantitative prediction of individual cognitive flexibility using structural MRI

Cognitive flexibility, a core dimension of executive functions, refers to one's ability to switch between multiple tasks and sets in a quick and flexible manner. However, whether objective neuroimaging can be used to quantitatively predict cognitive flexibility at the individual level remains largely unexplored. High-resolution magnetic resonance imaging data of 100 healthy young participants from the Human Connectome Project (HCP) dataset were used to calculate gray matter volume (GMV). Cognitive flexibility was assessed by the Dimensional Change Card Sort Test (DCCS). Using a multivariate machine learning technique known as relevance vector regression (RVR), we examined the relationship between GMV and cognitive flexibility performance. We found that the application of RVR to GMV allowed quantitative prediction of the DCCS scores with statistically significant accuracy (correlation = 0.41, P = 0.0001; mean squared error = 73.35, P = 0.0001). Accurate prediction was mainly based on GMV in the temporal regions. In addition, a univariate approach also revealed an inverse association between DCCS scores and GMV in the temporal areas. Our findings provide preliminary support to the development of neuroimaging techniques as a useful means to inform the cognitive assessment of individuals. Furthermore, the significant contribution of temporal regions suggests the prominent role of temporal cortex morphology in individual differences in cognitive flexibility.

Pineal gland abnormality in major depressive disorder

Patients with major depressive disorder (MDD) often have circadian rhythm alteration and sleep disturbance. The pineal gland regulates the circadian rhythm and sleep by the secretion of melatonin neurohormone. However, the relationship between pineal abnormality and MDD remains elusive. 50 patients with MDD and 35 gender- and age-matched healthy controls underwent high-resolution structural MRI. Pineal parenchymal volume (PPV) was measured manually. Inter-group differences in prevalence of pineal cyst and PPV were examined. In addition, we investigated the correlations between PPV and symptom severity as well as sleep variables in the patient group. Compared to healthy controls, patients with MDD had a higher prevalence of pineal cyst. Moreover, patients had significantly decreased PPV relative to controls. However, no significant correlations were observed between PPV and symptom severity as well as sleep variables. Our findings suggest that pineal abnormality may play a critical role in depression.

Abnormal coupling among spontaneous brain activity metrics and cognitive deficits in major depressive disorder

BACKGROUND

A variety of functional metrics derived from resting-state functional magnetic resonance imaging (rs-fMRI) have been employed to explore spontaneous brain activity changes in major depressive disorder (MDD) and have enjoyed significant success in unraveling the neurobiological mechanisms underlying this disorder. However, it is unclear whether spatial and temporal coupling relationships among these rs-fMRI metrics are altered in MDD.

METHODS

50 patients with MDD and 36 well-matched healthy controls underwent rs-fMRI scans. A dynamic analysis was applied to compute multiple frequently used metrics including fractional amplitude of low frequency fluctuations, regional homogeneity, voxel-mirrored homotopic connectivity, degree centrality and global signal connectivity. Kendall's W was used to calculate volume-wise (across voxels) and voxel-wise (across time windows) concordance among these metrics. Inter-group differences in the concordance and their associations with clinical and cognitive variables were tested.

RESULTS

Compared to healthy controls, patients with MDD showed decreased whole gray matter volume-wise concordance. Despite similar spatial distributions, quantitative comparison analysis revealed that MDD patients exhibited reduced voxel-wise concordance in multiple cortical and subcortical regions. Moreover, the lower concordance was associated with worse performances in prospective memory and sustained attention in the MDD group.

LIMITATIONS

The study design of fairly modest sample size did not allow us to perform a full analysis of the potential effects of medication and illness duration.

CONCLUSIONS

Our findings suggest that spatial and temporal decoupling of multiple resting-state brain activity metrics may help elucidate the neural mechanisms of cognitive deficits in depression.

[Antimicrobial resistance changes of carbapenem-resistant Enterobacteriaceae strains isolated from children]

Objective: To investigate the prevalence and resistance changes of carbapenem-resistant Enterobacteriaceae (CRE) strains isolated from children patients of Chinese Bacterial Resistance Surveillance Network (CHINET) from 2005 to 2017. Methods: Antimicrobial susceptibility testing was carried out by disk diffusion method (KB method) and automated systems. Results were analyzed according to the Clinical and Laboratory Standards Institute (CLSI) 2017 edition standards. Results: Among the 4 481 CRE clinical strains, the overall prevalence of CRE in children was 6.4%, including 8.8% in neonatal period, 7.3% in infancy, 3.8% in early childhood, 4.0% in preschool, 4.7% at school age and 7.4% of puberty. The CRE prevalence of citrobacter spp. remained stable in 2005-2017, whereas other bacteria showed an upward trend, which was higher than that of the adult group (P<0.01). Among the 4 481 CRE strains, there were 2 905 strains of Klebsiella spp. (64.8%), 813 strains of Escherichia coli (18.1%), 549 strains of Enterobacter spp.(12.3%), and 65 strains of Citrobacter spp.(1.5%). Among the 4 481 CRE strains, 20.7%, 13.3%, and 11.8% were from the intensive care unit (ICU), neonatal department and internal medicine wards, respectively. Specimens were distributed as respiratory (42.8%), urine (26.3%), and blood (14.9%). The results of antimicrobial susceptibility testing exhibited that the CRE strains were highly resistant to most commonly used antimicrobial agents in clinical practice, such as imipenem, meropenem and ertapenem, as well as penicillins and cephalosporins, etc. Conclusion: The prevalence of CRE strains in children is increasing year by year, and their antimicrobial resistance to common antibacterial agents in clinical practice is extremely serious, to which serious attention needs to be paid. According to the results of antimicrobial susceptibility testings, the antibacterial agents should be rationally selected to effectively control the spread of CRE.

The Relationship Between Serum Concentration of Vitamin D, Total Intracranial Volume, and Severity of Depressive Symptoms in Patients With Major Depressive Disorder

Background: Depression has been linked to vitamin D deficiency. However, little attention was paid to the neural substrate underlying this association. Methods: Fifty patients with major depressive disorder (MDD) were enrolled in this study. High-resolution structural magnetic resonance imaging was performed to calculate total intracranial volume (TIV). Peripheral venous blood samples were collected to measure serum vitamin D concentration. Hamilton Rating Scale for Depression (HAMD) was used to assess severity of depression symptoms. The relationship among TIV, serum vitamin D concentration, and HAMD score was examined using correlation, linear regression, and mediation analyses. Results: In patients with MDD, HAMD score was negatively correlated with TIV and serum vitamin D concentration, and TIV was positively correlated with serum vitamin D concentration. Linear regression analyses showed that TIV and serum vitamin D concentration were significant predictors of HAMD score. Importantly, mediation analysis revealed that TIV significantly mediated the relationship between serum vitamin D concentration and HAMD score. Conclusion: Our findings suggest that TIV may serve as a potential neural biomarker for monitoring responses to adjuvant therapy of vitamin D in patients with MDD.

Precise label-free leukocyte subpopulation separation using hybrid acoustic-optical chip

Leukocyte subpopulations contain crucial physiological information; hence, precise and specific leukocyte separation is very important for leukemia diagnosis and analysis. However, conventional centrifugation and immunofluorescence-based separation methods are inaccurate and inconvenient due to the overlapping cell size and density or complex marking processes. Herein, we report a new label-free technology for precise leukocyte subpopulation separation by synergy of acoustic and optical technologies. Standing surface acoustic wave (SSAW) solved the problem of gentle and precise focusing of cells in optical systems. In addition, SSAW was used for the separation of granulocytes, which have evident size distinction from other components. In case of lymphocytes and monocytes, which have overlap in size/density, optical force could distinguish them accurately based on the RI difference, with the convenience of acoustic pre-focusing. In this experiment, separation of three types of leukocyte subtypes with considerable throughput and purity was conducted, through which we obtained 99% pure lymphocytes, 98% pure monocytes, and 95% pure granulocytes. Experimental results prove that the device has robust ability in separating leukocyte phenotypes and have the advantages of being non-invasive, label-free and precise. In the future, this convenient hybrid method will be a potential powerful tool for auxiliary clinical diagnosis and analysis.

Altered spatial and temporal concordance among intrinsic brain activity measures in schizophrenia

Various data-driven voxel-wise measures derived from resting-state functional magnetic resonance imaging (rs-fMRI) have been developed to characterize spontaneous brain activity. These measures have been widely applied to explore brain functional changes in schizophrenia and have enjoyed significant success in unraveling the neural mechanisms of this disorder. However, their spatial and temporal coupling alterations in schizophrenia remain largely unknown. To address this issue, 88 schizophrenia patients and 116 gender- and age-matched healthy controls underwent rs-fMRI examinations. Kendall's W was used to calculate volume-wise (across voxels) and voxel-wise (across time windows) concordance among multiple commonly used measures, including fractional amplitude of low frequency fluctuations, regional homogeneity, voxel-mirrored homotopic connectivity, degree centrality and global signal connectivity. Inter-group differences in the concordance were investigated. Results revealed that whole gray matter volume-wise concordance was reduced in schizophrenia patients relative to healthy controls. Although two groups showed similar spatial distributions of the voxel-wise concordance, quantitative comparison analysis revealed that schizophrenia patients exhibited decreased voxel-wise concordance in gray matter areas spanning the bilateral frontal, parietal, occipital, temporal and insular cortices. In addition, these concordance changes were negatively correlated with onset age in schizophrenia patients. Our findings suggest that the concordance approaches may provide new insights into the neural mechanisms of schizophrenia and have the potential to be extended to neuropsychiatric disorders.

[The investigation on the historical remains related to medical, healthy and hygienical activities in Zhejiang]

Aiming to protect and utilize the historical remains related to medical, healthy, and hygienical activities, we have to get the information of those remains. From 2003 to 2018, we investigated and documented those remains before 1949 by checking various literatures, archives, and collected the information supplied by the traditional Chinese medicine practitioners and scholars. Total remains 167 recorded and documented as following: historical event remains 17; temple and shrine 12; medical institutions remains 43; research institutions remains 2; traditional Chinese medical factory remains 1; western and traditional Chinese medicine stores 15; western and Chinese medical education institutions remains 5; famous medical person residence remains 16; tombs 14; inscription 7; sites of wells 35, also including 1950s historical remains 2.

[General survey and protection of intangible cultural heritage in traditional medicine in Zhejiang Province]

From January 2003 to October 2008, the Zhejiang Provincial Department of Culture, together with the Intangible Cultural Heritage Management Department of 11 cities and counties, including Hangzhou, Ningbo, Wenzhou, Huzhou, Jiaxing, Shaoxing, Jinhua, Quzhou, Zhoushan, Taizhou, Lishui, surveyed the Province's intangible cultural heritage in traditional medicine, with a total of 7849 items, including 7 kinds of traditional medicine in 8 major categories: living Chinese medicine culture, ethnic medicine, acu-moxibustion, osteopathic therapy, unique therapies, and Chinese crude drugs, herbal medicine and traditional Chinese medicine preparation, TCM processing.Among them, 9 items have been included in the Representative Project List of National Traditional Medicine Intangible Cultural Heritage, 18 items were listed in Representative Project Directory of Zhejiang Traditional Medicine Intangible Cultural Heritage.Theprotection and inheritance of traditional of the intangible heritage of traditional medicine in Zhejiang province are mainly through the 4 batches of master guidance apprentices.In addition, protection is carried out through organizational support, literature systematization and other measures.

[Random notes on the hygienic works in the guerrilla of eastern Zhejiang Province of New Fourth Army]

Being reorganized on the basis of the 3rd and 5th branches of Songhu Guerrilla and its 3rd column, the Eastern Zhejiang Guerrilla got remarkable achievements in the health works from nothing. It is especially so and deserved written description for the Rear Hospitals of Sanbei when its medical staffs were surrounded by the Japanese and Kuomintang troops under very difficult conditions, which were overcome by the support of local people.

Effects of cyclopamine on the biological characteristics of human breast cancer MCF-7 cell line and its mechanism

PURPOSE

To observe the effects of cyclopamine on the biological characteristics of human breast cancer MCF-7 cell line and explore its mechanism.

MATERIALS AND METHODS

After human breast cancer MCF-7 cells were treated with different-concentration cyclopamine for different periods, MTT assay was used to detect the inhibitory effect of cyclopamine on MCF-7 cell proliferation, flow cytometry was used to determine the distribution of MCF-7 cell cycle and the effect of cyclopamine on MCF-7 apoptosis, and Western blot was used to measure the protein levels of cyclins D1 and p21 in MCF-7 cells.

RESULTS

In certain range, MCF-7 cell proliferation was inhibited by cyclopamine in a dose- and time-dependent manner, and the optimal inhibiting concentration was ten µmol/L and the optimal action time at 48 hours. With the time prolongation of cyclopamine action, the cells in G0/G1 phase were significantly increased, but the cells in S phase were significantly decreased (compared with blank control group, allp < 0.05). With the time prolongation of cyclopamine action, apoptosis rate of MCF-7 cells was also significantly increased (compared with blank control group, allp < 0.05). The level of cyclin D1 of MCF-7 cells was decreased, but cyclin p21 was increased (compared with blank control group, all p < 0.05).

CONCLUSION

Cyclopamine inhibits MCF-7 cell proliferation via arresting MCF-7 cell transformation from G1 phase to S phase. This may be associated with the expressions of Hedgehog (Hh) signaling pathway-related cyclins.

Limb ischemic preconditioning attenuates cerebral ischemic injury in rat model

Ischemic brain injury is not uncommon after open-heart surgery with cardiopulmonary bypass and seriously undermines the patients' life quality. Therefore, potential protective effects of limb ischemic preconditioning (LIP) on subsequent ischemic injury of the brain were investigated by evaluating anti-inflammatory effects and apoptosis of pyramidal neurons in the CA1 hippocampus. One hundred and eight Sprague-Dawley rats were divided into the middle cerebral artery occlusion (MCAO) group (n=54) and the LIP group (n=54). A thread was used to occlude the middle cerebral artery in the MCAO group and the LIP group animals were pretreated with LIP followed by MCAO. In the two groups, nine samples were collected at each time-point of 0, 6, 12, 24, 48 and 72 h after MCAO to detect IL-6 and IL-17 and their mRNA levels. Neurological severity scores (NSS) were examined before the animals were sacrificed. Compared with the LIP group, cerebral histopathological changes in the MCAO group were most distinct and significantly more infiltrated inflammatory and apoptotic neuronal cells were observed at 24, 48 and 72 h post-surgery. IL-17 and IL-6 mRNA levels analyzed by quantitative real-time polymerase chain reaction (PCR) (qRT-PCR) were significantly reduced in the LIP group compared with the MCAO group at the 12, 24 and 48 h time-points. A significant reduction in IL-17 expression level was determined by enzyme-linked immunosorbent assay (ELISA) in the LIP group at 12, 24 and 48 h, while IL-6 was significantly reduced at the 24 and 48 h time-points. The NSSs were not significantly different between the groups. Therefore, in a MCAO rat model, we have proved that LIP pretreatment can protect the brain from infarction after ischemic injury and induce ischemic tolerance, potentially, by reducing IL-17 to provide anti-inflammatory effects and attenuate apoptosis of hippocampal neuronal cells.

Lead inhibited N-methyl-D-aspartate receptor-independent long-term potentiation involved ryanodine-sensitive calcium stores in rat hippocampal area CA1

Lead exposure is known to be associated with cognitive dysfunction in children. Impairment of the induction of long-term potentiation (LTP) has been reported in area CA1 of rat hippocampus following lead exposure in vivo and in vitro. The present study was carried out to investigate whether the alterations of N-methyl-d-aspartate (NMDA) receptor-independent LTP following lead exposure involve internal calcium stores in hippocampus CA1 synapses. Monosynaptic field excitatory postsynaptic potentials in hippocampal slice area CA1 were recorded using the whole-cell patch-clamp upon acute lead treatment, and these studies were coupled with calcium imaging experiments to observe internal calcium changes in cultured hippocampal neurons. Inhibiting calcium release by ryanodine significantly reduced NMDA receptor-independent LTP, and depletion of internal calcium stores with thapsigargin blocked this form of LTP. Caffeine, an agonist of ryanodine receptors, enhanced this form of LTP. However, caffeine-enhanced NMDA receptor-independent LTP was depressed after bath application of lead. Moreover, lead further decreased ryanodine- and thapsigargin-reduced NMDA receptor-independent LTP. Calcium imaging also confirmed that lead had an effect on internal calcium release and uptake. Taken together, these results demonstrated that lead inhibited NMDA receptor-independent LTP by action on calcium release and uptake by ryanodine-sensitive stores in rat hippocampal area CA1.

Postantibiotic effects of eleven antimicrobials on five bacteria

AIM

To investigate the postantibiotic effects (PAE) of different classes of antimicrobials against five different types of bacteria.

METHODS

Minimal inhibitory concentrations (MIC) were determined by twofold macrodilution in broth. The antimicrobial agents were eliminated by washing method after the bacteria were exposed to antimicrobials for 1 h or 2 h. Growth curves were followed by viable counts, and then the PAE were calculated.

RESULTS

Macrolides induced PAE of 3.10 h to 4.15 h on S aureus, and 1.85 h to 3.3 h against S pneumoniae, which were longer than PAE induced by other tested antimicrobials (P<0.01). Macrolides induced PAE of 1 h to 4 h against H influenzae, with azithromycin producing the longest PAE of 4 h. Ciprofloxacin and amikacin induced PAE of 1.38 h to 2.00 h on E coli and K pneumoniae, which were longer than that of beta-lactams, piperacillin, cefazolin, or cefotaxime, with PAE of 0.1 h to 0.5 h (P<0.01).

CONCLUSION

Different classes of antimicrobials induce different periods of PAE. As an important pharmacodynamic parameter, PAE provide reference data for the determination of the optimal dosing regimen and reasonable use of antimicrobials.

Surveillance of bacterial resistance among isolates in Shanghai in 1999

We report here surveillance data on the bacterial resistance of clinical isolates from 11 Shanghai hospitals in 1999, for guidance in the clinical use of antibacterial agents. Of the 14,855 strains collected, 5130 (34.5%) were Gram-positive cocci and 9725 (65.5%) were Gram-negative bacilli. The most common organisms in descending order of frequency, were: Escherichia coli (16%), coagulase-negative staphylococci (CNS; 14.3%), Klebsiella spp. (12.3%), Staphylococcus aureus (11.5%), Pseudomonas aeruginosa (9.2%), Acinetobacter spp. (8.1%), and Enterococcus spp. (6.6%). Methicillin-resistant strains accounted for 64% and 77% of S. aureus and CNS, respectively. The methicillin-sensitive strains were susceptible to most agents tested, while most methicillin-resistant strains were resistant to these agents. No vancomycin-resistant staphylococci were identified. Vancomycin-resistant strains accounted for 3.6% of Enterococcus fecalis and 1.7% of E. fecium. E. coli strains resistant to piperacillin, gentamicin, and fluoroquinolones accounted for 50% or more of the strains, and the resistance rates of Klebsiella spp., Enterobacter spp., Citrobacter spp., and Acinetobacter spp. to third-generation cephalosporins had increased markedly compared with rates in recent years. Resistance rates of P. aeruginosa to ceftazidime and imipenem (27% and 20%, respectively) had also increased compared with rates in recent years. A national strategy on the limited and prudent use of antibiotics is urgently needed.

Thermal conductance and wettability of xenon on resorcinol-formaldehyde aerogels

We have performed thermal conductivity and adsorption isotherm measurements to investigate the system formed by Xe adsorbed on resorcinol-formaldehyde (RF) aerogel. Below 80 K, the thermal conductivity of the Xe/RF-aerogel system is essentially identical to that of the bare RF aerogel; however, above this temperature the thermal conductivity of the system increases significantly above that of the bare aerogel. Adsorption isotherm measurements indicate that Xe incompletely wets the RF aerogel below Xe's bulk triple point temperature. The thickness of the Xe film that forms on the RF aerogel decreases with decreasing temperature. By 80 K the total amount of Xe present on the aerogel in equilibrium with the saturated vapor pressure is less than the amount needed to form about 1.5 atomic layers of Xe on the substrate. We attribute the observed changes in the thermal conductivity of the Xe/aerogel system to changes in the wettability of the aerogel by the Xe film.

Frost heave in physisorbed films: vapor flow and substrate effects

The magnitude of vapor flow accompanying the surface-melted liquid flow in physisorbed multilayer films due to thermomolecular pressures was estimated. It was found that the vapor flow is significant compared to the flow of the surface-melted liquid in thick films. As the flows continue, the film thickness profile evolves into one determined by a dynamic equilibrium of vapor pressure. The flow of surface-melted liquid stops when the dynamic equilibrium is reached.

Frost heave in argon

The freezing of argon in silica powder is observed to generate bands of pure solid argon in the same manner as in the phenomenon of ice lens formation in the freezing of moist ground. A first principles dynamical theory describes the mechanism of lens formation by the thermomolecular pressure-driven flow of interfacially melted films at the lens-solid boundary.

Cathepsin inhibition induces apoptotic death in human leukemia and lymphoma cells

We examined the effects of cathepsin inhibitor 1 (CATI-1), a selective inhibitor of cysteine cathepsins, on human leukemia and lymphoma cells. CATI-1 induced apoptosis in all 12 cell lines tested. Apoptosis of CATI-1-treated leukemia/lymphoma cells was caspase-independent, p53-independent, BAX-independent as well as MAP kinase-independent. Our findings provide unprecedented experimental evidence that cathepsins play a pivotal role for the survival of human leukemia/lymphoma cells. Therefore, cathepsin inhibitors may provide the basis for new treatment programs against leukemia and lymphoma.

Calpain inhibitor II induces caspase-dependent apoptosis in human acute lymphoblastic leukemia and non-Hodgkin's lymphoma cells as well as some solid tumor cells

Calpain is a calcium-dependent cysteine protease that is implicated in calcium-dependent cell death, and calpain inhibitors are generally considered as inhibitors of apoptosis. To the contrary, in the present study, we found that calpain inhibitor II (CPI-2) triggers rapid apoptosis in acute lymphoblastic leukemia (ALL) and non-Hodgkin's lymphoma (NHL) cells. All target cell lines were killed by CPI-2, including: ALL-1, a multidrug-resistant BCR-ABL fusion transcript-positive t(9;22) pro-B ALL cell line; RS4;11, a highly radiation-resistant MLL-AF4 fusion transcript-positive t(4;11) pre-pre B ALL cell line; RAMOS, a highly radiation-resistant and p53-deficient Burkitt's lymphoma cell line; DAUDI, a Burkitt's leukemia/lymphoma cell line; NALM-6, a pre-B ALL cell line; and JURKAT and MOLT-3, two T-lineage ALL/NHL cell lines. CPI-2-induced apoptosis in LYN-deficient and BTK-deficient subclones of the DT-40 lymphoma B cell line as effectively as it did in wild-type DT-40 cells. Thus, CPI-2-induced apoptosis is not dependent on the protein tyrosine kinases LYN or BTK. Notably, caspase inhibitor I effectively inhibited CPI-2-induced apoptosis, suggesting that the inhibition of a CPI-2-susceptible protease results in caspase activation, leading to apoptosis in ALL/NHL cells. Unlike the high calpain-expressing ALL/NHL cell lines, myeloid leukemia cell lines HL-60/AML, K562/CML, and U937/AMML, or solid tumor cell lines BT-20/breast cancer, PC-3/prostate cancer, U373/glioblastoma, and HeLa/epitheloid cancer, were not susceptible to the cytotoxicity of CPI-2. Taken together, our results identify calpain as a new molecular target for the treatment of ALL and NHL. CPI-2 and its analogues represent a promising new class of antileukemia/lymphoma agents that deserves further development.

Z-Phe-Gly-NHO-Bz, an inhibitor of cysteine cathepsins, induces apoptosis in human cancer cells

An increasing number of studies indicate that cysteine cathepsins contribute to cancer progression, invasion, and metastasis. Here we provide experimental evidence that the cathepsin inhibitor Z-Phe-Gly-NHO-Bz induces rapid apoptotic death in human cancer cell lines. Notably, the Z-Phe-Gly-NHO-Bz-induced apoptosis exhibited independence of p53, caspases, and mitogen-activated protein (MAP) kinases. Taken together, our results prompt the hypothesis that cysteine cathepsin(s) is a universal survival factor for cancer cells, and its inhibition leads to cancer cell apoptosis. The exquisite sensitivity of human cancer cells to CATI-1 indicates that this compound and its derivatives may provide the basis for new treatment programs against a broad spectrum of malignancies.

Inositol tetrakisphosphate as a frequency regulator in calcium oscillations in HeLa cells

Cellular signaling mediated by inositol (1,4,5)trisphosphate (Ins(1, 4,5)P(3)) results in oscillatory intracellular calcium (Ca(2+)) release. Because the amplitude of the Ca(2+) spikes is relatively invariant, the extent of the agonist-mediated effects must reside in their ability to regulate the oscillating frequency. Using electroporation techniques, we show that Ins(1,4,5)P(3), Ins(1,3,4, 5)P(4), and Ins(1,3,4,6)P(4) cause a rapid intracellular Ca(2+) release in resting HeLa cells and a transient increase in the frequency of ongoing Ca(2+) oscillations stimulated by histamine. Two poorly metabolizable analogs of Ins(1,4,5)P(3), Ins(2,4,5)P(3), and 2,3-dideoxy-Ins(1,4,5)P(3), gave a single Ca(2+) spike and failed to alter the frequency of ongoing oscillations. Complete inhibition of Ins(1,4,5)P(3) 3-kinase (IP3K) by either adriamycin or its specific antibody blocked Ca(2+) oscillations. Partial inhibition of IP3K causes a significant reduction in frequency. Taken together, our results indicate that Ins(1,3,4,5)P(4) is the frequency regulator in vivo, and IP3K, which phosphorylates Ins(1,4, 5)P(3) to Ins(1,3,4,5)P(4), plays a major regulatory role in intracellular Ca(2+) oscillations.

Effects of physisorption of xenon on the thermal conductivity of resorcinol-formaldehyde aerogels

The effects of adsorption of xenon to the thermal conductivity of a resorcinol-formaldehyde aerogel were investigated in a temperature range from 20 to 120 K. It was found that at temperatures below 75 K, the adsorbed xenon has little effect on the thermal conductivity. Rapid rises of the thermal conductivity develop at temperatures around 75-80 K with magnitudes roughly proportional to the amount of xenon adsorbed. The effect is explained as due to adsorbed xenon atoms that enhance the neck connection between aerogel particles.

Pharmacokinetic features and metabolism of calphostin C, a naturally occurring perylenequinone with antileukemic activity

PURPOSE

To examine the pharmacokinetic features and metabolism of calphostin C, a naturally occurring perylenequinone with potent antileukemic activity.

METHODS

HPLC-based quantitative detection methods were used to measure calphostin C levels in lysates of leukemic cells and in plasma of mice treated with calphostin C. The plasma concentration-time data were analyzed using the WinNonlin program. In vitro esterases and a microsome P450 preparation in conjunction with a LC-MS(API-EI) system were used to study the metabolism of calphostin C.

RESULTS

An intracellular exposure level (AUC0-6h) of 257 microM x h was achieved after in vitro treatment of NALM-6 cells with calphostin C at a 5 microM final concentration in culture medium. After intraperitoneal (i.p.) injection of a 40 mg/kg nontoxic bolus dose of calphostin C, the estimated Cmax was 2.9 microM, which is higher than the effective in vitro concentration of calphostin C against leukemic cells. Drug absorption after i.p. administration was rapid with an absorption half-life of 24.2 min and the estimated t(max) was 63.0 min. Calphostin C was cleared with an elimination half-life of 91.3 min. An inactive and smaller metabolite (calphostin B) was detected in plasma of calphostin C-treated mice with a t(max) of 41.3 min. Esterase (but not P450) treatment of calphostin C in vitro yielded an inactive metabolite (calphostin B) of the same size and elution profile.

CONCLUSIONS

Target plasma calphostin C concentrations of potent antileukemic activity can be reached in mice at nontoxic dose levels. This pilot pharmacokinetic study of calphostin C combined with the availability of the described quantitative HPLC method for its detection in cells and plasma provide the basis for future preclinical evaluation of calphostin C and its potential as an anti-leukemic drug.

Quantitative high-performance liquid chromatography-based detection method for calphostin C, a naturally occurring perylenequinone with potent antileukemic activity

Calphostin C is a potent inhibitor of protein kinase C and can induce Ca2+-dependent apoptosis in human ALL cells. Further development of calphostin C will require detailed pharmacodynamic studies in preclinical animal models. Therefore, we established a sensitive and accurate high-performance liquid chromatography (HPLC)-based quantitative detection method for the measurement of calphostin C levels in plasma. Extraction of calphostin C from plasma was performed by precipitation of plasma protein using acetonitrile and an aliquot of extracted supernatant was injected onto a Hewlett-Packard HPLC system constituting a 250x4 mm LiChrospher 100, RP-18 (5 microm) in conjunction with a 4x4 mm LiChrospher 100, RP-18 guard column (5 microm). The eluted compounds were detected by diode array detection set at a wavelength of 479 nm. Acetonitrile-water containing 0.1% trifluoroacetic acid and 0.1% triethylamine (70:30, v/v) was used as the mobile phase. The average extraction recovery from plasma was 97.3%. Good linearity (r>0.999) was observed throughout the concentration range of 0.05-40 microM for calphostin C in 50 microl of plasma. Intra- and inter-assay variabilities were less than 6% in plasma. The lowest detection limit of calphostin C in 50 microl plasma was 0.02 microM at a signal-to-noise ratio of approximately 3. The availability of this assay will now permit detailed pharmacodynamic and pharmacokinetic studies of calphostin C in vivo.

A requirement for protein kinase C inhibition for calcium-triggered apoptosis in acute lymphoblastic leukemia cells

We have evaluated the cytotoxicities of the combinations of calcium mobilizers and PKC inhibitors against human acute lymphoblastic leukemia (ALL) cells. Here we report that calcium mobilizers alone or PKC inhibitors alone do not induce apoptosis in human ALL cells. However, the combinations of calcium mobilizers with potent inhibitors of PKC cause significant apoptosis in ALL cells. Our results provide experimental evidence that PKC blocks Ca2+-triggered apoptosis in human ALL cells. Thus, PKC inhibitors can be used to enhance the antileukemic activity of chemical or biological agents that trigger an apoptotic calcium signal in ALL cells. The exquisite sensitivity of ALL cells to calcium-dependent apoptosis in the presence of PKC inhibitors could provide the basis for new treatment programs against ALL.

Calphostin C triggers calcium-dependent apoptosis in human acute lymphoblastic leukemia cells

Recent studies have demonstrated that the naturally occurring perylenequinone antibiotic calphostin C is a potent inhibitor of protein kinase C and can induce apoptosis in some tumor cell lines by an as yet unknown mechanism. Here we demonstrate that calphostin C induces dose-dependent apoptosis in DT40 chicken lymphoma B-cells, and targeted disruption of lyn, syk, btk, PLCgamma2, or IP3R genes does not prevent or attenuate its cytotoxicity. In our study, calphostin C also induced rapid apoptosis in human acute lymphoblastic leukemia (ALL) cell lines ALL-1 (BCR-ABL+ pre-pre-B ALL), RS4;11 (MLL-AF4+ pro-B ALL), NALM-6 (pre-B ALL), DAUDI (Burkitt's/B-cell ALL), MOLT-3 (T-ALL), and JURKAT (T-ALL), whereas other potent PKC inhibitors did not. In biochemical studies, calphostin C was discovered to induce rapid calcium mobilization from intracellular stores of ALL cell lines, and its cytotoxicity against ALL cell lines was well correlated with the magnitude of this calcium signal. Calphostin C-induced apoptosis was markedly suppressed by BAPTA/AM, a cell-permeable Ca2+ chelator as well as NiCl2, an inhibitor of Ca2+/Mg2+-dependent endonucleases. Inhibition of the Ca2+/calmodulin-dependent phosphatase calcineurin with perfluoreperazine dimadeate (a calmodulin antagonist) or cyclosporin A (a specific inhibitor of calcineurin) also reduced the magnitude of calphostin C-induced apoptosis in ALL cell lines. Calphostin C was capable of inducing calcium mobilization and apoptosis in freshly obtained primary leukemic cells from children with ALL. Taken together, our results provide unprecedented evidence that calphostin C triggers a Ca2+-dependent apoptotic signal in human ALL cells.

The carriage of Escherichia coli resistant to antibiotics in healthy populations in Shanghai

Healthy populations represent the largest reservoir of bacteria resistant to antibiotics. We investigated the resistance of Escherichia coli to 12 antibiotics in fecal samples from untreated healthy populations in Shanghai, China by using Kirby-Bauer (K-B) method. The results showed that: (i) All subjects carried resistant strains of Escherichia coli. (ii) The carriage rates of Escherichia coli resistant to various antibiotics were different, less than 10% to amikacin and 30% to 100% to others. (iii) In the elder children group aged 10-11 years, the percentages of strains resistant to gentamicin, streptomycin, chloramphenicol, tetracycline, trimethoprim, and sulfamethoxazole were significantly lower than those in the younger group aged 5-6 years. In the adult group, the percentages of strains resistant to ampicillin, piperacillin, amikacin, streptomycin, chloramphenicol, tetracycline, trimethoprim, and sulfamethoxazole were significantly lower than those in the elder children group. (iv) The number of strains resistant to five or more antibiotics accounted for 31.8% in the younger children group, 23.7% in the elder children group, and 12.1% in the adult group. These findings suggest that all healthy people in Shanghai carry resistant strains of Escherichia coli in the intestine. The younger the populations, the higher the level of resistance of fecal Escherichia coli to antibiotics. Improvement of health behaviors and environmental sanitation and rational use of antibiotics could remarkedly decrease the resistant level of bacteria.

Modified ultrafiltration in paediatric cardiopulmonary bypass

Cardiopulmonary bypass (CPB), a nonphysiological procedure, is associated with haemodilution and the inflammatory response, causing the accumulation of body water and organ dysfunction. The purpose of this study was to evaluate the efficacy of modified ultrafiltration. Forty paediatric patients undergoing cardiac operations were randomized into a control group and a modified ultrafiltration group. Blood cells, protein and cytokine concentrations were recorded for 24 h postoperatively. As the fluid was removed at 50 ml/min, both blood cells and protein were concentrated by modified ultrafiltration (p < 0.001). The tumour necrosis factor (TNF)-alpha concentration was increased and interleukin-8 (IL-8) and endothelin (ET) concentrations were unaltered after ultrafiltration. After correction for albumin, TNF-alpha concentration changed little, and IL-8 and ET concentrations (36.75 +/- 12.35, 42.89 +/- 15.54) were decreased significantly (21.47 +/- 13.87, 26.06 +/- 12.54) after ultrafiltration. Modified ultrafiltration is an effective method for removing excess tissue fluid and concentrating blood after CPB. This technique can also filter out some cytokines.

Low affinity interaction of human or rat T cell adhesion molecule CD2 with its ligand aligns adhering membranes to achieve high physiological affinity

The mechanism by which low affinity adhesion molecules function to produce stable cell-cell adhesion is unknown. In solution, the interaction of human CD2 with its ligand CD58 is of low affinity (500 mM-1) and the interaction of rat CD2 with its ligand CD48 is of still lower affinity (40 mM-1). At the molecular level, however, the two systems are likely to be topologically identical. Fluorescently labeled glycosylphosphatidylinositol-anchored CD48 and CD58 were prepared and incorporated into supported phospholipid bilayers, in which the ligands were capable of free lateral diffusion. Quantitative fluorescence imaging was used to study the binding of cell surface human and rat CD2 molecules to the fluorescent ligands in contact areas between Jurkat cells and the bilayers. These studies provide two major conclusions. First, CD2/ligand interactions cooperate to align membranes with nanometer precision leading to a physiologically effective two-dimensional affinity. This process does not require the intact cytoplasmic tail of CD2. Second, the degree of membrane alignment that can be achieved by topologically similar receptors deteriorates with decreasing affinity. This suggests an affinity limit for the ability of this mode of cooperativity to achieve stable cell-cell adhesion at approximately 10 mM-1.