Independent and combined effects of methamphetamine use disorders and APOEε4 allele on cognitive performance and brain morphometry

AIMS

Prior studies showed that methamphetamine (METH) users had greater than normal age-related brain atrophy; whether having the apolipoprotein E (APOE)-ε4 allele may be a contributory factor has not been evaluated. We aimed to determine the independent and combined effects of chronic heavy METH use and having at least one copy of the APOE-ε4 allele (APOE-ε4+) on brain morphometry and cognition, especially in relation to aging.

METHODS

We compared brain morphometry and cognitive performance in 77 individuals with chronic heavy METH use (26 APOE-ε4+, 51 APOE-ε4-) and 226 Non-METH users (66 APOE-ε4+, 160 APOE-ε4-), using a 2 × 2 design (two-way analysis of co-variance). Vertex-wise cortical volumes, thickness and seven subcortical volumes, were automatically measured using FreeSurfer. Linear regression between regional brain measures, and cognitive scores that showed group differences were evaluated. Group differences in age-related decline in brain and cognitive measures were also explored.

RESULTS

Regardless of APOE-ε4 genotype, METH users had lower Motor Z-scores (P = 0.005), thinner right lateral-orbitofrontal cortices (P < 0.001), smaller left pars-triangularis gyrus volumes (P = 0.004), but larger pallida, hippocampi and amygdalae (P = 0.004-0.006) than nonusers. Across groups, APOE-ε4+ METH users had the smallest volumes of superior frontal cortical gyri bilaterally, and of the smallest volume in left rostral-middle frontal gyri (all P-values <0.001). Smaller right superior-frontal gyrus predicted poorer motor function only in APOE-ε4+ participants (interaction-P < 0.001). Cortical volumes and thickness declined with age similarly across all participants; however, APOE-ε4-carriers showed thinner right inferior parietal cortices than noncarriers at younger age (interaction-P < 0.001).

CONCLUSIONS

Chronic heavy use and having at least one copy of the APOE-ε4 allele may have synergistic effects on brain atrophy, particularly in frontal cortices, which may contribute to their poorer cognitive function. However, the enlarged subcortical volumes in METH users replicated prior studies, and are likely due to METH-mediated neuroinflammation.

Neuronal and Glial Metabolite Abnormalities in Participants With Persistent Neuropsychiatric Symptoms After COVID-19: A Brain Proton Magnetic Resonance Spectroscopy Study

BACKGROUND

The aim of this study was to determine whether neurometabolite abnormalities indicating neuroinflammation and neuronal injury are detectable in individuals post-coronavirus disease 2019 (COVID-19) with persistent neuropsychiatric symptoms.

METHODS

All participants were studied with proton magnetic resonance spectroscopy at 3 T to assess neurometabolite concentrations (point-resolved spectroscopy, relaxation time/echo time = 3000/30 ms) in frontal white matter (FWM) and anterior cingulate cortex-gray matter (ACC-GM). Participants also completed the National Institutes of Health Toolbox cognition and motor batteries and selected modules from the Patient-Reported Outcomes Measurement Information System.

RESULTS

Fifty-four participants were evaluated: 29 post-COVID-19 (mean ± SD age, 42.4 ± 12.3 years; approximately 8 months from COVID-19 diagnosis; 19 women) and 25 controls (age, 44.1 ± 12.3 years; 14 women). When compared with controls, the post-COVID-19 group had lower total N-acetyl compounds (tNAA; ACC-GM: -5.0%, P = .015; FWM: -4.4%, P = .13), FWM glutamate + glutamine (-9.5%, P = .001), and ACC-GM myo-inositol (-6.2%, P = .024). Additionally, only hospitalized patients post-COVID-19 showed age-related increases in myo-inositol, choline compounds, and total creatine (interaction P = .029 to <.001). Across all participants, lower FWM tNAA and higher ACC-GM myo-inositol predicted poorer performance on several cognitive measures (P = .001-.009), while lower ACC-GM tNAA predicted lower endurance on the 2-minute walk (P = .005).

CONCLUSIONS

In participants post-COVID-19 with persistent neuropsychiatric symptoms, the lower-than-normal tNAA and glutamate + glutamine indicate neuronal injury, while the lower-than-normal myo-inositol reflects glial dysfunction, possibly related to mitochondrial dysfunction and oxidative stress in Post-COVID participants with persistent neuropsychiatric symptoms.

Long-term use of Lacticaseibacillus paracasei N1115 from early life alleviates high-fat-diet-induced obesity and dysmetabolism in mice

Obesity has become one of the most serious public health problems worldwide, and an increasing number of studies indicate that the gut microbiota can affect host metabolism. Therefore, the present study was conducted to evaluate whether long-term use of probiotics can alleviate host obesity and metabolism by altering gut microbiota. The high-fat diet (HFD) starting from weaned period led to higher levels of visceral fat and a significantly heavier liver in male mice. Moreover, HFD resulted in disorders of glucose and lipid metabolism, changes in insulin-resistance indices (IR), and an increase in serum insulin and leptin in mice. Of note, 15 weeks use of Lacticaseibacillus paracasei N1115 decreased visceral fat, liver weight, serum levels of insulin and leptin, and IR and alleviated lipid dysmetabolism. HFD resulted in a significant increase in the relative abundance of Bilophila, Lachnoclostridium, and Blautia and may decrease the faecal short-chain fatty acid (SCFA) levels in mice; in turn, treatment with the potential probiotic strain L. paracasei N1115 protected mice from these negative effects. HFD significant impaired the physiology of the host especially in male mice and dramatically changed the composition of host gut microbiota. However, the use of potential probiotic strain, such as L. paracasei N1115, may prevent these impairments due to HFD via effecting the host gut microbiota and SCFA.

Contributions of chronic tobacco smoking to HIV-associated brain atrophy and cognitive deficits

OBJECTIVES

Tobacco smoking is linked to cognitive deficits and greater white matter (WM) abnormalities in people with HIV disease (PWH). Whether tobacco smoking additionally contributes to brain atrophy in PWH is unknown and was evaluated in this study.

DESIGN

We used a 2 × 2 design that included 83 PWH (43 nonsmokers, 40 smokers) and 171 HIV-seronegative (SN, 106 nonsmokers, 65 smokers) participants and assessed their brain structure and cognitive function.

METHODS

Selected subcortical volumes, voxel-wise cortical volumes and thickness, and total WM volume were analyzed using FreeSurfer. Independent and interactive effects of HIV and smoking were evaluated with two-way analysis of covariance on cognitive domain Z-scores and morphometric measures on T1-weighted MRI.

RESULTS

Regardless of smoking status, relative to SN, PWH had smaller brain volumes [basal ganglia, thalami, hippocampi, subcortical gray matter (GM) and cerebral WM volumes (P = 0.002-0.042)], steeper age-related declines in the right superior-parietal (interaction: P < 0.001) volumes, and poorer attention/working memory and learning (P = 0.016-0.027). Regardless of HIV serostatus, smokers tended to have smaller hippocampi than nonsmokers (-0.6%, P = 0.055). PWH smokers had the smallest total and regional subcortical GM and cortical WM volume and poorest cognitive performance.

CONCLUSIONS

Tobacco smoking additionally contributed to brain atrophy and cognitive deficits in PWH. The greater brain atrophy in PWH smokers may be due to greater neuronal damage or myelin loss in various brain regions, leading to their poor cognitive performance. Therefore, tobacco smoking may exacerbate or increase the risk for HIV-associated neurocognitive disorders.

[The prevention and management of approach-specific complications of abdominal aortic balloon occlusion in pelvic and sacral surgery]

Objective: To investigate the causes,prevention and treatment of femoral artery puncture related complications caused by the application of resuscitative endovascular balloon occlusion of the aorta (REBOA) in the resection of pelvic and sacral tumors. Methods: Clinical data of 23 patients with femoral artery puncture related complications who received REBOA in the resection of pelvic and sacral tumors from August 2010 to August 2018 at the Musculoskeletal Tumor Center,Peking University People's Hospital were retrospectively analyzed.There were 8 males and 15 females,with the an age of (37.0±16.2) years (range:15 to 65 years).Arterial access via the Seldinger technique for REBOA was obtained in the right common femoral artery of 18 cases,and in the left of 6 cases.An arterial sheath with a diameter of 11 to 12 F(1 F≈0.33 mm) was used for the patient.The occurrence and treatment of postoperative complications were analyzed. Results: Acute femoral arterial thrombosis occurred in 18 patients,which was managed by open repair 48 hours postoperatively.Among the 349 patients admitted before 2015 who received hemostasis by compression after femoral artery sheath removal,12 patients (3.4%) developed acute femoral artery thrombosis.While the 476 patients admitted after 2015 who used a vascular stapler to close the femoral artery wound,6 patients (1.3%) developed acute femoral artery thrombosis.One case of retroperitoneal hematoma and 1 case of femoral pseudoaneurysm were found and surgically fixed.Postoperative follow-up was (40±18) months (range:13 to 108 months).Three cases with chronic lower extremity ischemia were confirmed by Doppler ultrasonography during 1 to 5 years follow-up.Two of them had minimal symptoms and denied further treatment,while the other one received femoral-femoral artery bypass surgery to restore distal flow for pain and numbness relief. Conclusions: Acute femoral arterial thrombosis was the most common femoral artery puncture.Technique refinement of REBOA,the use of percutaneous suture device and close follow-up can reduce the approach-specific complications,and help to detect and treat the complications timely,which may popularize the clinical application of REBOA.

Dysbiosis of intestinal microbiota in early life aggravates high-fat diet induced dysmetabolism in adult mice

BACKGROUND

Accumulating evidence have shown that the intestinal microbiota plays an important role in prevention of host obesity and metabolism disorders. Recent studies also demonstrate that early life is the key time for the colonization of intestinal microbes in host. However, there are few studies focusing on possible association between intestinal microbiota in the early life and metabolism in adulthood. Therefore the present study was conducted to examine whether the short term antibiotic and/or probiotic exposure in early life could affect intestinal microbes and their possible long term effects on host metabolism.

RESULTS

A high-fat diet resulted in glucose and lipid metabolism disorders with higher levels of visceral fat rate, insulin-resistance indices, and leptin. Exposure to ceftriaxone in early life aggravated the negative influences of a high-fat diet on mouse physiology. Orally fed TMC3115 protected mice, especially those who had received treatment throughout the whole study, from damage due to a high-fat diet, such as increases in levels of fasting blood glucose and serum levels of insulin, leptin, and IR indices. Exposure to ceftriaxone during the first 2 weeks of life was linked to dysbiosis of the fecal microbiota with a significant decrease in the species richness and diversity. However, the influence of orally fed ceftriaxone on the fecal microbiota was limited to 12 weeks after the termination of treatment. Of note, at week 12 there were still some differences in the composition of intestinal microbiota between mice provided with high fat diet and antibiotic exposure and those only fed a high fat diet.

CONCLUSIONS

These results indicated that exposure to antibiotics, such as ceftriaxone, in early life may aggravate the negative influences of a high-fat diet on the physiology of the host animal. These results also suggest that the crosstalk between the host and their intestinal microbiota in early life may be more important than that in adulthood, even though the same intestinal microbes are present in adulthood.

[An investigation of insulin injection-related needlestick injuries among clinical nurses in Hunan, China]

Objective: To investigate the incidence rate of insulin injection-related needlestick injuries, links causing such injuries, and reporting of occupational exposure among nurses in the wards of general hospitals in Hunan, China. Methods: From January 2017 to March 2019, stratified cluster sampling was performed to select 4368 nurses as respondents from 54 hospitals at different levels in 14 prefectures and cities of Hunan. The current status of insulin injection-related needlestick injuries was investigated, including the high-risk links causing insulin injection-related needlestick injuries during the use of insulin syringe (pen) , time and number of needlestick injuries, infection after needlestick injuries, and reporting of needlestick injuries, and a statistical analysis was performed. Continuous data were described as mean±standard deviation, and categorical data were described by percentage (%) . Results: Among the 3697 nurses who were investigated, 1419 (38.4%) once had needlestick injuries related to insulin injection, among whom 413 (29.1%) had needlestick injuries in the past 1 year. The mean number of insulin injection-related needle stick injuries was 1.92±1.80, with a mean number of 0.57±1.18 caused by insulin syringe, 1.30±1.15 caused by the anterior segment of insulin pen, and 0.32±0.81 caused by the posterior end of insulin pen. Among the 1419 nurses with a history of needlestick injuries, 90 (6.3%) had related infection, mainly HBV infection, and after the occurrence of needlestick injuries, 26.0% (369/1419) of these nurses reported it every time and 15.2% (215/1419) never reported it. "Fear of trouble" was the main reason for no reporting (69.1%, 980/1419) , followed by "the thought of no risk" (43.2%, 613/1419) and "no related policy in hospital" (10.9%, 154/1419) ". Among these 1419 nurses, 49.8% (706/1419) were treated according to the standard process for needlestick injuries in hospital every time, and 3.6% (51/1419) did not know such process or there was no such standard process. Conclusion: The current situation of insulin injection-related needlestick injuries is not optimistic among clinical nurses in Hunan, and the incidence rate of needlestick injuries cannot be ignored.

Microstructural brain abnormalities in HIV+ individuals with or without chronic marijuana use

OBJECTIVE

Cognitive deficits and microstructural brain abnormalities are well documented in HIV-positive individuals (HIV+). This study evaluated whether chronic marijuana (MJ) use contributes to additional cognitive deficits or brain microstructural abnormalities that may reflect neuroinflammation or neuronal injury in HIV+.

METHOD

Using a 2 × 2 design, 44 HIV+ participants [23 minimal/no MJ users (HIV+), 21 chronic active MJ users (HIV + MJ)] were compared to 46 seronegative participants [24 minimal/no MJ users (SN) and 22 chronic MJ users (SN + MJ)] on neuropsychological performance (7 cognitive domains) and diffusion tensor imaging metrics, using an automated atlas to assess fractional anisotropy (FA), axial (AD), radial (RD), and mean (MD) diffusivities, in 18 cortical and 4 subcortical brain regions.

RESULTS

Compared to SN and regardless of MJ use, the HIV+ group had lower FA and higher diffusivities in multiple white matter and subcortical structures (p < 0.001-0.050), as well as poorer cognition in Fluency (p = 0.039), Attention/Working Memory (p = 0.009), Learning (p = 0.014), and Memory (p = 0.028). Regardless of HIV serostatus, MJ users had lower AD in uncinate fasciculus (p = 0.024) but similar cognition as nonusers. HIV serostatus and MJ use showed an interactive effect on mean diffusivity in the right globus pallidus but not on cognitive function. Furthermore, lower FA in left anterior internal capsule predicted poorer Fluency across all participants and worse Attention/Working Memory in all except SN subjects, while higher diffusivities in several white matter tracts also predicted lower cognitive domain Z-scores. Lastly, MJ users with or without HIV infection showed greater than normal age-dependent FA declines in superior longitudinal fasciculus, external capsule, and globus pallidus.

CONCLUSIONS

Our findings suggest that, except in the globus pallidus, chronic MJ use had no additional negative influence on brain microstructure or neurocognitive deficits in HIV+ individuals. However, lower AD in the uncinate fasciculus of MJ users suggests axonal loss in this white matter tract that connects to cannabinoid receptor rich brain regions that are involved in verbal memory and emotion. Furthermore, the greater than normal age-dependent FA declines in the white matter tracts and globus pallidus in MJ users suggest that older chronic MJ users may eventually have lesser neuronal integrity in these brain regions.

Ground-to-satellite time and frequency synchronization link with active carrier phase compensation

In this paper, a synchronization link between one ground station and one geostationary satellite is established. The ground station receives retransmitted signals from the satellite, measures phase delay along the propagation route, and actively compensates back to its sending signals, realizing real-time phase fluctuation compensation. The transmitted signal contains two frequencies to eliminate common-mode phase noise. The difference between their carrier phase delays is measured. Different modes of carrier phase variation are separated and compensated, achieving a remaining time jitter of ±200 ps. Major sources of error are analyzed, and potential methods for improvement are discussed. The proposed ground-to-satellite link and active compensation method has potential applications in frequency standard dissemination to remote receivers (including ground stations or satellites). These potential applications justify further study of this system.

[Soft-tissue angiosarcoma with pulmonary metastases: case report and literature review]

Objective: To investigate the differential diagnosis between pulmonary metastases from soft-tissue angiosarcoma and primary pulmonary angiosarcoma. Methods: A case of soft-tissue angiosarcoma with pulmonary metastases was reported and related literatures were reviewed. Results: A 39 year-old man complaining of hemoptysis, cough, and sputum for 10 months was admitted to our hospital in September 2013. He was initially diagnosed as having primary pulmonary angiosarcoma after wedge-resection biopsy of the lung. After 22 months since onset, he felt discomfort in his leg, which led to the confirmative diagnosis of soft-tissue angiosarcoma of the leg with multiple pulmonary metastases by a full-body PET/CT scan and core needle biopsy of the leg. Twenty-three articles concerning primary pulmonary angiosarcoma with complete records of history, treatment and follow-up of patients were included in the literature review. A total of 26 patients were reported in these articles, including 18 males, 8 females, age 19-85 years, average (52±18) years. Primary pulmonary angiosarcoma was mainly manifested as single or multiple pulmonary nodules or masses, with or without ground glass opacity. In our case, chest CT showed multiple thin-wall cysts and ground glass opacities, and recurrent spontaneous pneumothorax, which had never been reported in literatures on primary pulmonary angiosarcoma. Conclusions: Pulmonary metastases from soft-tissue angiosarcoma differed from primary pulmonary lesions in terms of chest imaging, with the former usually showing thin-wall cysts and pneumothorax. A full-body PET-CT was essential for differential diagnosis between primary and metastatic pulmonary angiosarcoma.

Analysis of drug-resistant gene detection of blaOXA-like genes from Acinetobacter baumannii

Our study determines the resistance gene profile of a set of Acinetobacter baumannii hospital isolates. A. baumannii is responsible for nosocomial outbreaks and sporadic infections. We extracted and PCR amplified bacterial DNA isolated from patients with ages below 60 years (23.36%) and above 60 years (76.64%). Most of the patients were admitted in the ICU (36.13%) and pneumology departments (28.47%). Of 164 isolated strains, 16 (9.75%) contained OXA-51, 8 (4.88%) contained OXA-58, and 140 (85.37%) contained both OXA-51 and OXA-23. Additionally, 8 (7.41%) strains containing OXA-58 and 100 (92.59%) strains containing both OXA-51 and OXA-23 showed multidrug-resistance. Drug resistance rates of A. baumannii to amikacin, tobramycin-levofloxacin, and cotrimoxazole were above 90%, while drug resistance rates to ampicillin, cefotetan, cefazolin, cefoperazone, and nitrofurantoin were 100%. In conclusion, we found that isolated strains containing OXA-51 and OXA-23 were more likely to be resistant or have decreased sensitivity to carbapenems.

Lack of association between EPHX1 polymorphism and esophageal cancer risk: evidence from meta-analysis

The microsomal epoxide hydrolase 1 (EPHX1) Tyr113His and His139Arg polymorphisms have been reported to be associated with esophageal cancer (EC) risk, yet the results of these previous results have been inconsistent or controversial. The objective of this study was to explore whether the EPHX1 Tyr113His and His139Arg polymorphisms confer risk to EC. The relevant studies were identified through a search of PubMed, Excerpta Medica Database (Embase), Elsevier Science Direct, and Chinese Biomedical Literature Database until May 2013. The association between the EPHX1 Tyr113His and His139Arg polymorphisms and EC risk was pooled by odds ratios (ORs) together with their 95% confidence intervals (95%CIs). A total of eight case-control studies with 1163 EC patients and 1868 controls (seven studies for both Tyr113His and His139Arg polymorphisms, one study only for Tyr113His polymorphism) were eventually identified. We found no association between EPHX1 Tyr113His and His139Arg polymorphisms and EC risk in overall population (For Tyr113His: His vs. Tyr: OR = 1.05, 95%CI = 0.95-1.15, P = 0.379; His/His vs. Tyr/Tyr: OR = 1.04, 95%CI = 0.88-1.22, P = 0.208; His/Tyr vs. Tyr/Tyr: OR = 0.96, 95%CI = 0.80-1.15, P = 0.577; His/His vs. His/Tyr + Tyr/Tyr: OR = 1.10, 95%CI = 0.96-1.26, P = 0.164; His/His + His/Tyr vs. Tyr/Tyr: OR = 1.01, 95%CI = 0.90-1.12, P = 0.543. For His139Arg: Arg vs. His: OR = 1.04, 95%CI = 0.94-1.14, P = 0.465; Arg/Arg vs. His/His: OR = 1.06, 95%CI = 0.91-1.24, P = 0.470; Arg/His vs. His/His: OR = 1.03, 95%CI = 0.91-1.16, P = 0.673; Arg/Arg vs. Arg/His + His/His: OR = 1.04, 95%CI = 0.85-1.27, P = 0.708; Arg/Arg + Arg/His vs. His/His: OR = 1.02, 95%CI = 0.93-1.13, P = 0.617). In subgroup analysis based on ethnicity, significant association has been found in neither EPHX1 Tyr113His nor His139Arg polymorphism. The current meta-analysis suggests no evidence of association between the EPHX1 polymorphism and EC risk.

Thrombin generation and fibrin formation under flow on biomimetic tissue factor-rich surfaces

BACKGROUND

Blood flow regulates coagulation and fibrin assembly by controlling the rate of transport of zymogens, enzymes and plasma proteins to and from the site of an injury.

OBJECTIVE

The objective of this work was to define the hemodynamic conditions under which fibrin can form under flow on tissue factor (TF)-rich substrates.

METHODS

TF-coated silica beads (~ 800 nm) were patterned into 18-85-μm spots. Normal pooled plasma and factors VIII, IX and XI deficient plasmas were perfused over the beads coated with 0.08, 0.8 and 8 molecules-TF μm(-2) at shear rates of 50-1000 s(-1) . Fibrin deposition and thrombin generation were measured by fluorescence microscopy in a hydrodynamic focusing microfluidic device.

RESULTS AND CONCLUSIONS

Fibrin deposition was supported on patterned bead spots, but not planar TF substrates at the same surface TF concentration. There was a threshold spot size and a shear rate dependent TF concentration that was necessary to support fibrin polymerization. FVIII and FIX had minor effects on fibrin dynamics at 8 molecules-TF μm(-2) , but were essential at 0.8 molecules-TF μm(-2) . The absence of FXI influenced thrombin generation and fibrin deposition at both 0.8 and 8 molecules-TF μm(-2) . These results show that fibrin deposition requires perturbations in the flow field that protect reactions from dilution by flow under venous and arterial conditions. FVIII and FIX have a modest effect on fibrin deposition at high TF concentrations, but are necessary for fibrin deposition at low TF concentrations. FXI amplifies thrombin generation under flow at both low and high TF concentrations.

Relationship between cognitive impairment and depressive symptoms in current ketamine users

OBJECTIVE

Both cognitive impairment and depressive symptoms have been reported in ketamine users. However, no previous study has examined the relationship between them. This study aimed to examine cognitive functions and depressive symptoms and their relationship in young ketamine users in Hong Kong.

METHOD

Fifty-one current ketamine users, 49 ex-ketamine users, and 100 healthy controls were recruited from counseling and youth centers in Hong Kong in this cross-sectional study. Cognitive assessment included mental and motor speed; working, verbal, and visual memory; and executive functions. Depressive symptoms were measured using the Beck Depression Inventory. One-way analyses of covariance (ANCOVA) and chi-square tests were used to analyze participants' demographic data, patterns of drug use, Beck Depression Inventory score, and performance in a cognitive battery. Cognitive functions were adjusted for age, gender, and education using ANCOVA. Correlations between the Beck Depression Inventory score and cognitive functions were examined using Pearson's correlation coefficient.

RESULTS

Cognitive impairment was found only in current ketamine users in the domains of mental and motor speed (p < .001), visual and verbal memory (p < .001), and executive functions (p < .001). Depressive symptoms were also more frequently found in current ketamine users (p < .001). Correlations between depressive symptoms and certain cognitive scores were statistically significant but modest.

CONCLUSIONS

Current ketamine use is associated with cognitive impairment. Illicit substance treatment and rehabilitation services should pay attention to ketamine's cognitive effects and motivate their clients to quit using ketamine and stay abstinent.

Location of infarcts and apathy in ischemic stroke

BACKGROUND

Apathy is common in stroke survivors. Unlike poststroke depression, apathy after stroke has not been extensively investigated and the significance of the location of infarcts in the development of apathy following a stroke is unknown. This study examined the association between poststroke apathy (PSA) and the location of infarcts.

METHODS

A cohort of 185 patients with acute ischemic stroke admitted to the Stroke Unit of a university-affiliated regional hospital in Hong Kong was recruited. Three months after the index stroke, a psychiatrist administered the Apathy Evaluation Scale (AES). PSA was defined as an AES score of 37 or above. The presence and location of infarcts were evaluated with magnetic resonance imaging.

RESULTS

Altogether 185 patients met the entry criteria and formed the study sample; 20 (10.8%) had PSA. PSA patients were older and had higher stroke severity and more depressive symptoms. The PSA group also had lower levels of physical and cognitive functioning. Compared with the non-PSA group, PSA patients were more likely to have acute pontine infarcts (35.0% vs. 11.5%; p = 0.011). They had a higher mean number (0.5 ± 0.7 vs. 0.1 ± 0.3; p = 0.003) and larger volume (0.6 ± 1.4 vs. 0.1 ± 0.3 ml; p = 0.002) of acute pontine infarcts. Six variables were entered into the predictive regression model: age, the presence, number and volume of acute pontine infarcts, the number of old infarcts and periventricular white matter hyperintensities scores. The volume of infarcts remained an independent predictor of PSA in the multivariate analysis, with an odds ratio of 3.9 (p = 0.007). The Geriatric Depression Scale, National Institutes of Health Stroke Scale, Barthel Index and Mini-Mental State Examination scores were also entered into the subsequent associative regression model; the volume of acute pontine infarcts remained a significant predictor (odds ratio = 3.8).

CONCLUSIONS

This is the first report of an association between pontine infarcts and the risk of PSA. The results suggest that pontine infarcts may play a role in the development of PSA. The importance of acute pontine infarcts in the pathogenesis of PSA warrants further investigation.

Serotonin receptor 2C gene polymorphism associated with post-stroke depression in Chinese patients

The serotonin receptor 2C (HTR2C) gene has been shown to play a pivotal role in major depression. We examined the association between post-stroke depression (PSD) and polymorphism in HTR2C. A cohort of 223 patients with acute lacunar stroke admitted to the stroke unit of a university-affiliated regional hospital in Hong Kong was recruited. Three months after the onset of the index stroke, a research assistant administered the locally validated 15-item Geriatric Depression Scale. PSD was defined as a geriatric depression scale score of 7 or above. Possible confounding factors, including previous history of stroke, severity of stroke, level of social support, and recent life events, were investigated. All patients were genotyped for polymorphisms of HTR2C. Separate analyses were performed for males and females. Sixty-one patients were found to have PSD. There were significant associations between the HTR2C gene and PSD status in the male patients, but not in the female ones. After adjusting for possible confounders, the rs12837651 T allele (odds ratio = 4.020) and the rs2192371 G allele (odds ratio = 2.866) were found to be significantly associated with PSD in males. Genetic variation in HTR2C receptors appears to be involved in the pathogenesis of PSD in Chinese males.

Clinical characteristics of cough mixture abusers referred to three substance abuse clinics in Hong Kong: a retrospective study

OBJECTIVES. Cough mixture is the third most commonly abused substance in patients attending the Prince of Wales Hospital Substance Abuse Clinic. The content of the local cough mixture is not well researched. Paranoid psychosis manifesting as persecutory delusions and derogatory hallucination, as well as mood symptoms, is common in these patients. The natural history and outcome of such psychoses associated with cough mixture abuse are not well known. This study aimed to address these questions. METHODS. This was a retrospective study of cough mixture abuse in Hong Kong. Case records of cough mixture abusers currently receiving treatment at the 3 substance abuse clinics at the Prince of Wales Hospital, Alice Ho Miu Ling Nethersole Hospital, and the North District Hospital were retrieved for data collection. The patients' demographic data, duration and intake pattern of cough mixture, and use of any other drugs were documented. The presenting psychopathology, first urine toxicology results, diagnosis, treatment, number of hospitalizations, and course of the illness were also recorded. RESULTS. A total of 63 patients with the diagnosis of cough mixture abuse were identified in the database; 89% were male. The mean +/- SD age of the patients was 34.4 +/- 6.2 years; 67% were single and 83% were unemployed. The mean +/- SD age of onset of cough mixture abuse was 20 +/- 5 years. Psychiatric symptoms developed a mean +/- SD of 7.6 +/- 6.0 years after onset of abuse. According to the ICD-10 Mental and Behavioural Disorders criteria, the top psychiatric diagnoses were substance-induced psychotic disorder (67%), schizophrenia (19%), depressive disorder (11%), and dysthymia (10%). The most common ingredients in the urine sample at first presentation were promethazine (75%), pseudoephedrine (67%), codeine (60%), ephedrine (57%), zopiclone (17%), and hydrocodone (16%). Additionally, 16% of patients were in the priority follow-up group. The mean +/- SD follow-up period was 6.2 +/- 7.1 years during which there were 3.2 +/- 3.7 episodes of hospitalizations, with a mean +/- SD length of stay in each admission of 25.0 +/- 40.9 days. CONCLUSIONS. Promethazine, ephedrine, pseudoephedrine, codeine, and hydrocodone are the most common ingredients of cough mixture abused in this locality. Psychotic disorders are the most frequent psychiatric diagnosis associated with cough mixture abuse.

Poststroke fatigue is associated with caudate infarcts

OBJECTIVE

The caudate nucleus may be involved in the pathogenesis of the fatigue observed in neurological disorders. However, the significance of caudate lesions in poststroke fatigue (PSF) is unknown. This study examined the association between caudate infarcts and PSF.

METHODS

Five hundred Chinese patients with acute ischemic stroke admitted to the acute stroke unit of a university-affiliated regional hospital in Hong Kong participated in the study. All participants were assessed for PSF with the Fatigue Severity Scale (FSS) three months after their index stroke. PSF was defined as a mean FSS score of 4.0 or more. Physical functioning and depressive symptoms were measured by the Barthel Index (BI) and the Geriatric Depression Scale (GDS).

RESULTS

One hundred and twenty-five (25.0%) of the patients had PSF. Compared to the non-fatigue group, the PSF patients were more likely to be women and had hyperlipidemia, lower BI and higher GDS scores. Caudate (8.0% versus 1.3%, p=0.001) and putamen (19.2% versus 12.0%, p=0.043) acute infarcts were more common in the PSF group, whereas pons infarcts (13.6% versus 22.2%, p=0.038) were less common. Acute caudate infarcts remained an independent predictor of PSF in the multivariate analysis, with an odds ratio of 6.4.

CONCLUSIONS

The results suggest that patients with PSF are more likely to have caudate infarcts.

Referral patterns and clinical characteristics of subjects referred to substance abuse clinic of a regional hospital in Hong Kong

OBJECTIVES

To examine the clinical characteristics of subjects referred to the Substance Abuse Clinic of the Prince of Wales Hospital between 1 January 2007 and 31 December 2009 in Hong Kong.

METHODS

A chart review of 131 subjects referred to the Substance Abuse Clinic during the study period was carried out. Psychiatric diagnoses were made by a psychiatrist, according to the 10th edition of the International Classification of Diseases.

RESULTS

Social workers were increasingly a main source of referrals, accounting for 34% of referrals during the entire study period (and 43% in 2009). Another important referral source was the Hospital Authority system in Hong Kong, which accounted for 38% of referrals over the 3-year study period. Ketamine, methamphetamine, and cough mixtures were the most common drugs of primary misuse, the proportion of users being 34%, 24% and 12%, respectively. In these referals, the most common psychiatric diagnosis was substance-induced psychotic disorder, followed by depressive disorder, made in 44% and 22% of the subjects, respectively.

CONCLUSIONS

Among Hong Kong substance abusers, psychotic and depressive disorders are common, and ketamine is the most commonly misused drug.

Psychiatric morbidity at a female residential drug treatment centre in Hong Kong

OBJECTIVE

To describe the psychiatric co-morbidity of female psychotropic substance abusers treated at a residential treatment centre.

METHODS

Subjects were recruited from a female residential substance abuse treatment centre in Hong Kong--the Society for the Aid and Rehabilitation for Drug Abusers. Demographic data and substance abuse habits were recorded. Psychiatric diagnoses were established with the Structured Clinical Interview for the 4th edition of the Diagnostic and Statistical Manual of Mental Disorders.

RESULTS

Of the 42 residents, 32 agreed to participate in the study. All of whom completed the questionnaire and the Structured Clinical Interview for the 4th edition of the Diagnostic and Statistical Manual of Mental Disorders. Concerning substance abuse, 84%, 38%, and 34% of the subjects were dependent on ketamine, methamphetamine and cocaine, respectively. The most common lifetime psychiatric diagnosis was substance-induced mood disorder (47%), followed by substance-induced psychotic disorder (16%).

CONCLUSIONS

Psychiatric disorders complicate heavy substance abuse in the majority of female patients. Regular screening of this population with standardised diagnostic instruments for psychiatric comorbidity is clearly warranted.

Enhancement of the foaming properties of protein dried in the presence of trehalose

Surface tension, foamability, and foam stability kinetics have been measured for the pure proteins bovine serum albumin (BSA) and beta-lactoglobulin, before and after aqueous solutions of the proteins had been subjected to different drying conditions, and also for whey protein concentrate (WPC). Pure proteins were air-dried, at 78 or 88 degrees C, in the presence and absence of sucrose or trehalose, at a mass ratio of 5:1 sugar/protein. WPC was spray-dried in the presence of various sugars: trehalose, sucrose, lactose, and lactitol. Spray-drying WPC without sugars resulted in a dramatic decrease in the foam stability, whereas drying in the presence of sugars gave better retention of the original foaming properties. Trehalose in particular resulted in almost complete retention of the foam stability observed for the nondried WPC. Pure beta-lactoglobulin showed similar behavior, but trehalose did not seem to afford the same protection to BSA.

Oxidative injury induced by synthetic humic acid polymer and monomer in cultured rabbit articular chondrocytes

Humic substance has been proposed as one of the causative factors of Kashin-Beck disease (KBD), an endemic osteoarthritic disorder with necrosis of chondrocytes widely prevalent in some regions of China. In order to exclude the complications of natural humic substance, here we prepared phenolic polymers of synthetic humic acid (SHA) by oxidation of phenolic monomer, the protocatechuic acid (PCA). The biological effects of SHA and PCA on primary culture of rabbit articular chondrocytes were investigated. We found that not only SHA but also PCA caused chondrocyte injury, as evidenced by the loss of cell viability measured with methylthiazol tetrazolium (MTT) assay and the increased release of intracellular lactate dehydrogenase (LDH). Both SHA and PCA could result in lipid peroxidation and glutathione (GSH) depletion in chondrocytes, indicating that oxidative stress may be involved in chondrocyte injury. Furthermore, a marked increase in intracellular calcium level ([Ca2+]i) occurred after chondrocytes treated with SHA or PCA. These results suggest that chondrocyte injury elicited by SHA or PCA may be mediated through the occurrence of oxidative stress and the disruption of intracellular Ca2+ homeostasis. Data also suggest that the monomeric phenolic acid may be considered one of the causative factors of KBD in addition to humic substance.

Methyl methanesulfonate and hydrogen peroxide differentially regulate p53 accumulation in hepatoblastoma cells

Genotoxic chemicals not only damage cellular DNA, but may also induce cell apoptosis if they are lethal to the cell. p53, Bcl-2 and Bax play important roles in the regulation of genotoxic chemical induced cell apoptosis. Since the mechanisms by which cellular DNA damaged by different DNA-damaging chemicals may not be the same, we studied the involvement of p53, Bcl-2 and Bax in apoptosis induced by methyl methanesulfonate (MMS) and hydrogen peroxide (H2O2). H2O2 damages DNA by free radical generation and MMS damages DNA by DNA methylation. At non-lethal doses, both H2O2 and MMS induced high level of p53 protein accumulation. Nevertheless, while the amount of p53 protein increased with the dose of MMS and the occurrence of apoptotic cell death events, H2O2 doses that induce cell apoptosis attenuated the p53 protein accumulation level. Lethal MMS treatment also increased Bax, but not Bcl-2 expression, whereas in H2O2 induced apoptosis, the level of both Bcl-2 and Bax declined. These results indicate that toxic chemicals differentially regulate the accumulation of p53 protein. Thus, the pathways of toxic chemicals induced cell apoptosis are different and independent.

Oxidative stress induced by humic acid solvent extraction fraction in cultured rabbit articular chondrocytes

Kashin-Beck disease (KBD), an endemic, chronic osteoarthritic disorder with necrosis of chondrocytes, commonly occurs in China. The humic substance present in the drinking water of endemic areas has been proposed as one of the causative factors. In this study an in vitro cell culture system was used to investigate the damaging effects of humic acid (HA), a constituent of humic substance, on cultured rabbit articular chondrocytes. The commercial Aldrich humic acid (AHA) was fractionated with a series of organic solvents including n-hexane, benzene, ethyl acetate, and methanol. Among the several fractions of AHA, the ethyl acetate fraction (AHA-[EA]) displayed the most potent inhibitory effect on the survival of chondrocytes in clonogenic assays. Cellular injury induced by AHA-[EA] was evaluated by measuring cell viability with methylthiazol tetrazolium (MTT) and by determining the release of intracellular lactate dehydrogenase (LDH). Incubation of chondrocytes with AHA-[EA] (100-500 microg/ml) for 12 h produced a concentration-dependent decrease in cell viability and increase in LDH release. In addition, AHA-[EA] triggered lipid peroxidation manifested by elevated malondialdehyde (MDA) formation. In chemiluminescence assay, AHA-[EA] at the concentrations of 150-600 microg/ml caused 6- to 15-fold increases of luminol-amplified chemiluminescence responses, which are considered to reflect the production of hydrogen peroxide (H2O2). Moreover, pretreating the cells with 500-750 U/ml of catalase significantly prevented the loss of cell viability, while superoxide dismutase (SOD) enhanced the adverse effect of 300 microg/ml AHA-[EA]. Data suggest that the injury to chondrocytes induced by AHA-[EA] may be first through O2.- production, which is then converted into H2O2, thus initiating lipid peroxidation and leading to chondronecrosis observed in KBD.

Neuroimmunomodulation with enkephalins: enhancement of human natural killer (NK) cell activity in vitro

To further define the effects of enkephalins on immune function, the effect of methionine-enkephalin and leucine-enkephalin on natural killer cell (NK) activity in isolated human peripheral blood lymphocytes was investigated. Incubation of lymphocytes with either enkephalin resulted in significant increases in natural killer cell activity. At effector:target cell ratios of 11:1 methionine-enkephalin significantly (P less than 0.05) enhanced NK activity at dilutions of 10(-6), 10(-8), 10(-10), and 10(-14) mg/ml, while leucine-enkephalin significantly (P less than 0.05) enhanced NK activity at dilutions of 10(-4), 10(-6), 10(-8), 10(-10), and 10(-14) mg/ml. Cells from individuals with low NK activity showed greater percentage increases in NK activity following enkephalin than did cells from individuals with high NK activity.