[Clinical effect of superior oblique re-tucking for recurrent or residual compensatory head position]

Objective: To evaluate the effects of re-tucking the superior oblique muscle on recurrent or residual compensatory head position. Methods: A retrospective case series study was conducted. 12 recurrent or residual compensatory head position patients (12 eyes) with congenital superior oblique palsy who underwent superior oblique re-tucking in Tianjin Eye Hospital from March 2015 to February 2021 were included. All patients had a history of superior oblique tucking procedure and showed signs of superior oblique muscle palsy without inferior oblique muscle overaction. During surgery, the Guyton forced duction test is used to evaluate the relaxation of the superior oblique muscle tendon, which affects the re-tucking length of the muscle.Their head position, vertical deviation, eye movement, fovea-disa angle, and Bielschowsky head tilt test were assessed pre-and post-surgery. Statistical analysis was performed using ttest and paired samples Wilcoxon signed rank test. Results: Out of the 12 patients, 8 were male and 4 were female, aged between 2 and 9 years. The initial surgery was done at age 6, with a superior oblique recession length of (7.17±1.03) mm. Recurrent head tilt occurred in 11 patients after (3.82±0.98) months postoperatively, and 1 patient had residual head tilt, with a followup period of six months or more. Ocular motility examination revealed underaction of the superior oblique muscle, positive Bielschowsky's head tilt test, and Guyton forced duction tese indicating relaxation of the paralyzed superior oblique muscle tendon. Scar adhesion was observed at the stop of the superior oblique muscle, as well as the previous sutures. The scar and the sutures around the stop of the superior oblique muscle were released, the mean re-tucking amount was(7.83±1.59)mm. Follow-up at 12 to 18 months postoperatively showed disappearance of compensatory head position, significant improvement in superior oblique muscle lag, normal ocular motility, and no occurrence of Brown syndrome. The results of Bielschowsky head tilt were negative in 9 cases and still positive in 3 cases after superior oblique re-tucking. The primary vertical deviation was 2.5 (2.0, 5.3) prism diopter pre-operatively and 1 (0, 1) prism diopter post-operatively, respectively. The difference was statistically significant (U=6.00, P<0.001). The total amount of FDA in both eyes was (-22.04±5.47)° and (-15.27±6.08)° pre-and post-operatively, respectively. The difference was statistically significant (t=2.87, P=0.009). All 12 patients have normal eye movement after superior oblique re-tucking procedure. All patients had no compensatory head position at last follow-up. Conclusions: Superior oblique re-tucking is suitable for patients with relaxation of the superior oblique muscle tendon and extrocular rotation as the main sign. It can effectively and safely correct the recurrent or residual compensatory head position after re-tucking the superior oblique muscle.

Association between traumatic events with suicidality among adolescents: A large-scale cross-sectional study of 260,423 participants

Traumatic events have significant negative impacts throughout one's life. We aimed to comprehensively examine the early associations between traumatic events and suicidality among adolescents. In a cross-sectional sample of 260,423 adolescents in Deyang, China in September 2021, we assessed individual traumatic events, cumulative types, and patterns, alongside suicide risk scores and ideation, attempts, or plans. Linear and Poisson regression models adjusted for demographic confounders evaluated the association. Robust associations existed between interpersonal violence-related traumatic events and higher suicidality, with physical abuse demonstrating the strongest correlation. Moreover, suicide risk scores displayed a clear trend, indicating a progressively stronger association with suicidality as cumulative traumatic event types increased. Four distinct traumatic patterns emerged, including low traumas, high physical abuse, high death/serious injuries of a loved one, and multiple traumas, with the latter showing the strongest association with suicidality. Notably, the stratified analysis showed these associations were more pronounced in females, urban residents, only children, left-behind children, and those aged 13-15, while weaker in participants from families with intact parental relationships and middle socioeconomic status. Understanding the role of demographic factors and traumatic patterns in identifying at-risk youth can enable early detection and targeted interventions for suicide-related concerns.

Influencing factors of non-suicidal self-injury according to DSM-5 in adolescents admitted to the psychiatric department: a cross-sectional study

BACKGROUND

Non-suicidal self-injury (NSSI) is being increasingly recognized as a prominent mental health concern, especially among adolescents. In psychiatric clinical samples, its incidence is high and difficult to identify. However, few studies have explored the NSSI behavior of psychiatric hospitalized adolescents. This study aimed to explore the influencing factors of NSSI according to the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5) in adolescents admitted to the psychiatric department.

METHODS

In this cross-sectional study, by convenient sampling, a total of 505 psychiatric adolescent inpatients aged 10-19 years completed questionnaires to record details of sociodemographic characteristics, the NSSI questionnaire, the Child Psychological Abuse and Neglect Scale (CPANS), the self-report version of the Strengths and Difficulties Questionnaire (self-report SDQ), the Coping Style Scale for Middle School Students (CSSMSS), which were compared between NSSI inpatients and non-NSSI inpatients. This study used the diagnostic criteria for NSSI disorder in DSM-5: adolescent patients who have NSSI behaviors for more than 5 times in the past 1 year are called NSSI. A multiple logistic regression model was built to explore the relationships among general information, CPANS, SDQ, CSSMSS, and NSSI. Risk for NSSI is quantified by odds ratio (OR) with 95% confidence interval (CI).

RESULTS

The results showed that 77.82% (n=393) of adolescent inpatients had NSSI, and 80.0% were female (n=404). NSSI adolescent inpatients experienced more family scolding, psychological abuse, and neglect and showed more positive attitudes toward NSSI than non-NSSI adolescent inpatients. However, after controlling for covariables, the difference disappeared. NSSI behavior was significantly associated with female (OR =2.391, 95% CI: 1.396-4.097, P=0.002), younger age (10-14 years old) (OR =1.876, 95% CI: 1.154-3.049, P=0.011), have close friends (OR =0.355, 95% CI: 0.164-0.768, P=0.008), peer discussion about self-injury (OR =1.977, 95% CI: 1.047-3.734, P=0.036), emotional and behavioral difficulties (OR =1.853, 95% CI: 1.054-3.258, P=0.032), problem-oriented coping styles (OR =0.968, 95% CI: 0.945-0.991, P=0.007), emotion-oriented coping styles (OR =1.035, 95% CI: 1.006-41.064, P=0.016).

CONCLUSIONS

Measures should be taken to prevent and reduce the occurrence of NSSI behaviors among hospitalized adolescents in psychiatric department, which include improving adolescents' attitude towards NSSI, reducing adolescents' gathering behavior in the ward, preventing adolescents from discussing NSSI through social media, improving their coping style when facing difficulties, and reasonably regulating their abnormal emotions and behaviors.

Striving to improve investment efficiency among Chinese firms: does the role of venture capital matter?

Purpose

This study aims to investigate the impact of venture capital (VC) involvement on investment efficiency (IE) and its potential action mechanisms from the perspective of financial resource allocation.

Design/methodology/approach

Using data of Chinese firms between 2008 and 2020, and the propensity score matching–difference in differences method, the authors investigate the relationship between VC and IE.

Findings

The results show that VC involvement significantly promotes IE, and the effect exhibits an inverted U-shape dynamic over time. The authors find two mechanisms through which VC promotes IE: alleviating financing constraints and improving corporate governance. Supplementary tests indicate that VC institutions with high reputations play a significant role in enhancing IE; the promotion effect is more pronounced for firms in non-high-tech industries, firms facing higher industrial competition and firms located in areas with better property rights protection systems.

Originality/value

This study provides several original contributions. First, based on principal–agent and financing constraint theories, this study enhances the literature by revealing how VC drives the IE of newly public firms in China. Second, to the best of the authors’ knowledge, this is the first attempt to identify the mechanisms between VC and IE; Third, from an empirical perspective, besides discussing the average and dynamic effect of VC on IE, this study also explores the impact of the interaction between VC and market competition and property rights protection on IE.

Menopause-Related Symptoms and Influencing Factors in Mosuo, Yi, and Han Middle-Aged Women in China

Although previous studies showed that women’s menopause-related symptoms varied in different ethnic groups and countries, and were affected by specific social and cultural factors, few studies have been conducted to explore menopause-related symptoms and its influencing factors in middle-aged women among ethnic groups in China. This study aimed to explore the characteristics of menopause-related symptoms and its influencing factors among Mosuo, Yi, and Han women in Yongning area of Yunnan province, China. A cross-cultural design by snowball sampling method was used to recruit 208 women aged 40–60 from Yongning Township, Ninglang County, Yunnan province, China. The 11-item Menopause Rating Scale (MRS) was used to assess menopause-related symptoms. Compared with Yi and Han women, Mosuo women were accorded the highest family status. Multiple linear regression analyses showed that ethnicity, age, family support, and family decision-making patterns were associated with the severity of menopause-related symptoms. Yi and Han women had more severe menopause-related symptoms than Mosuo women. Among the three groups, women living in “female-dominated” and “co-deliberated” households had significantly lower scores of menopause-related symptoms than those in “male-dominated” households. This study indicates that menopause-related symptoms vary among middle-aged women in different ethnic groups. A higher level of female status in the family and family support may be protective factors of menopause-related symptoms in middle-aged women.

Widowhood and depression among Chinese older adults: examining coping styles and perceptions of aging as mediators and moderators

Objectives: Based on the stress-coping framework, this study examined the role of coping styles and perceptions of aging in the relationship between widowhood and depression through two alternative pathways-mediation and moderation-with a national probability sample of older adults in China.Method: The data came from the baseline wave of the China Longitudinal Aging Social Survey of 2014. Our final sample featured 8,404 older adults.Results: The results of structural equation modeling showed a good fit for the total sample (NFI = .909, IFI = .916, GFI = .963, RMSEA = .038) and indicated the significant direct impact of widowhood on depression among Chinese older adults. Moreover, the findings of mediating effects found compared with a married group, widowed older adults used less problem-focused coping and had more negative perceptions of aging, which in turn, predicted higher depression; they were also more likely to use emotion-focused coping, which in turn, predicted lower depression. The results of moderation analysis demonstrated that a higher level of negative perceptions of aging significantly worsened the adverse effects of widowhood on depression.Conclusion: Overall, our findings highlight the importance of a cognitive approach to targeting programs for widowed older adults in China, with a focus on strengthening their abilities to alter maladaptive copings styles and reauthor their life narratives.

Effects of COVID-19 on career and specialty choices among Chinese medical students

Coronavirus disease 2019 (COVID-19) pandemic has brought unprecedented challenges to medical education systems and medical students. The aim of this study was to investigate the effects of COVID-19 pandemic on medical career and specialty choices among medical students. An online cross-sectional survey of Chinese medical students was conducted during the COVID-19 pandemic from February to April 2020. The students' willingness to be a doctor before and after the COVID-19 pandemic and changed willingness to specialize in respiratory medicine and infectious diseases were investigated. Multiple linear regression and binary logistic regression was used to explore factors that were associated with changes of willingness. A total of 1,837 medical students, including 1,227 females (66.8%), with a median age of 21.0 years, were recruited. Of the participants, 10.6% and 6.9% showed increased and decreased willingness to be a doctor after the COVID-19 outbreak, respectively. Moreover, 11.7% showed increased willingness and 9.5% showed decreased willingness to major in respiratory medicine and infectious diseases. Students with younger age, lower household income, fewer depressive symptoms, less exposure to negative pandemic information and more satisfaction with their own major after the pandemic were associated with increased willingness to be a doctor. Students who engaged in regular exercise, were males and undergraduate level, were interested in medicine, paid more attention to positive information, were satisfied with their majors, and had increased willingness to be a doctor after the pandemic were more likely to choose to specialize in respiratory medicine and infectious disease. However, the severity of anxiety symptoms was associated with decreased willingness to work in the specialties of respiratory medicine and infectious diseases. Psychological problems and professional satisfaction appear to be independent factors that affect medial career and specialty choices. The impacts of the COVID-19 pandemic on medical students require further research.

Prevalence and Risk Factors of Mental Health Symptoms and Suicidal Behavior Among University Students in Wuhan, China During the COVID-19 Pandemic

Background: University students who are exposed to coronavirus disease 2019 (COVID-19) could be mentally distressed. We aimed to evaluate the pattern and risk factors of mental health and suicidal behavior among students who experienced long-term school closure due to the COVID-19 pandemic. Methods: This large-sample, cross-sectional, online survey was conducted from June 29, 2020, to July 18, 2020. Eleven thousand two hundred fifty four participants were recruited from 30 universities located in Wuhan, Hubei Province, China. The prevalence of symptoms of depression, anxiety, insomnia, and posttraumatic stress disorder (PTSD) and suicidal behavior was evaluated using the Patient Health Questionnaire-9, Generalized Anxiety Disorder-7, Insomnia Severity Index, Posttraumatic Stress Disorder Checklist for DSM-5, and questions about suicidal ideation and attempts, respectively. Logistic regression was used to explore risk factors for mental health problems and suicidal behavior. Results: The prevalence of mental health problems was 41.5% for depressive symptoms, 32.6% for anxiety symptoms, 35.0% for insomnia symptoms, 8.5% for PTSD symptoms, and 2.0% for suicidal behavior. Participants with high stress during the pandemic were at higher risk of symptoms of depression [adjusted odds ratio (OR) = 1.67, 95% confidence interval (CI) = 1.43-1.95, p < 0.01), anxiety (adjusted OR = 1.90, 95% CI = 1.63-2.23, p < 0.01), insomnia (adjusted OR = 1.64, 95% CI = 1.44-1.87, p < 0.01), PTSD (adjusted OR = 1.71, 95% CI = 1.38-2.11, p < 0.01) and suicidal behavior (adjusted OR = 3.51, 95% CI = 2.28-5.40, p < 0.01). Distant relationship with parents, changes in lifestyle and alcohol use during the pandemic were associated with higher risk of mental health symptoms and suicidal behavior, whereas regular physical exercise reduced the risk of mental health problems. Conclusions: The psychological symptoms and suicidal behavior were relatively high among students who attended university in Wuhan, China after 6 months of the COVID-19 outbreak in China. Comprehensive mental health services and suicide prevention strategies are essential for university students during the COVID-19 pandemic.

Association of Symptoms of Attention Deficit and Hyperactivity with Problematic Internet Use among University Students in Wuhan, China During the COVID-19 Pandemic

BACKGROUND

COVID-19 is still spreading worldwide and posing a threat to individuals' physical and mental health including problematic internet use (PIU). A potentially high-risk group for PIU are those with symptoms of attention deficit and hyperactivity (ADHD symptoms), because of restrictions in their physical activity levels and engagement in computer diversions requiring only short attention spans.

METHODS

We used convenience sampling in a cross-sectional survey of university students from 30 universities in Wuhan, Hubei Province, China. We assessed PIU using the Internet Addiction Test and ADHD symptoms using the WHO Adult ADHD Self-Report Screening Scale. Using logistic regression and linear regression analyses we adjusted for demographic, epidemic-related and psychological covariates in models of the association between ADHD symptoms and PIU.

RESULTS

Among 11,254 participants, we found a 28.4% (95% CI, 27.5%-29.2%) prevalence of PIU, relatively higher than before the pandemic. In our final logistic regression model, participants with ADHD symptoms had approximately two times the risk for PIU (OR: 2.31, 95% CI: 1.89-2.83). Similarly, individuals with depression, anxiety, insomnia, PTSD symptoms and feeling stress during the pandemic had a higher risk of PIU, while those exercising regularly during the pandemic had a lower risk.

LIMITATIONS

The cross-sectional design and reliance on internet based self-reports for ADHD symptoms and PIU assessments, without direct structured interviews for validation, are limitations.

CONCLUSIONS

The prevalence of PIU was high during COVID-19, and those people with ADHD symptoms and other mental illness symptoms appear to be at higher risk of PIU. Regular exercise may reduce that PIU risk and hence should be recommended during the COVID-19 pandemic.

APOE-ε4 Carrier Status and Gut Microbiota Dysbiosis in Patients With Alzheimer Disease

BACKGROUND

Alternations in gut microbiota and a number of genes have been implicated as risk factors for the development of Alzheimer disease (AD). However, the interactions between the altered bacteria and risk genetic variants remain unclear.

OBJECTIVE

We aimed to explore associations of the risk genetic variants with altered gut bacteria in the onset of AD.

METHODS

We collected baseline data and stool and blood samples from 30 AD patients and 47 healthy controls in a case-control study. The rs42358/rs4512 (ApoE), rs3851179 (PICALM), rs744373 (BIN1), rs9331888 (CLU), rs670139 (MS4A4E), rs3764650 (ABCA7), rs3865444 (CD33), rs9349407 (CD2AP), rs11771145 (EPHA1), and rs3818361/rs6656401 (CR1) were sequenced, and microbiota composition was characterized using 16S rRNA gene sequencing. The associations of the altered gut bacteria with the risk genetics were analyzed.

RESULTS

Apolipoprotein ε4 allele and rs744373 were risk loci for the AD among 12 genetic variants. Phylum Proteobacteria; orders Enterobacteriales, Deltaproteobacteria, and Desulfovibrionales; families Enterobacteriaceae and Desulfovibrionaceae; and genera Escherichia-Shigella, Ruminococcaceae_UCG_002, Shuttleworthia, Anaerofustis, Morganelia, Finegoldia, and Anaerotruncus were increased in AD subjects, whereas family Enterococcaceae and genera Megamonas, Enterococcus, and Anaerostipes were more abundant in controls (P < 0.05). Among the altered microbiota, APOE ε4 allele was positively associated with pathogens: Proteobacteria.

CONCLUSION

The interaction of APOE ε4 gene and the AD-promoting pathogens might be an important factor requiring for the promotion of AD. Targeting to microbiota might be an effective therapeutic strategy for AD susceptible to APOE ε4 allele. This needs further investigation.

The impact of quarantine on mental health status among general population in China during the COVID-19 pandemic

Quarantine and isolation measures urgently adopted to control the COVID-19 pandemic might potentially have negative psychological and social effects. We conducted this cross-sectional, nationwide study to ascertain the psychological effect of quarantine and identify factors associated with mental health outcomes among population quarantined to further inform interventions of mitigating mental health risk especially for vulnerable groups under pandemic conditions. Sociodemographic data, attitudes toward the COVID-19, and mental health measurements of 56,679 participants from 34 provinces in China were collected by an online survey from February 28 to March 11, 2020. Of the 56,679 participants included in the study (mean [SD] age, 36.0 [8.2] years), 27,149 (47.9%) were male and 16,454 (29.0%) ever experienced home confinement or centralized quarantine during COVID-19 outbreak. Compared those without quarantine and adjusted for potential confounders, quarantine measures were associated with increased risk of total psychological outcomes (prevalence, 34.1% vs 27.3%; odds ratio [OR], 1.34; 95% CI, 1.28-1.39; P < 0.001). Multivariable logistic regression analyses showed that vulnerable groups of the quarantined population included those with pre-existing mental disorders or chronic physical diseases, frontline workers, those in the most severely affected areas during outbreak, infected or suspected patients, and those who are less financially well-off. Complying with quarantine, being able to take part in usual work, and having adequate understanding of information related to the outbreak were associated with less mental health issues. These results suggest that quarantine measures during COVID-19 pandemic are associated with increased risk of experiencing mental health burden, especially for vulnerable groups. Further study is needed to establish interventions to reduce mental health consequences of quarantine and empower wellbeing especially in vulnerable groups under pandemic conditions.

Psychological impact of the COVID-19 pandemic on healthcare workers: a cross-sectional study in China

BACKGROUND

Healthcare workers fighting against the coronavirus disease 2019 (COVID-19) pandemic are under tremendous pressure, which puts them at an increased risk of developing psychological problems.

AIMS

This study aimed to investigate the prevalence of psychological problems in different healthcare workers (ie, physicians, medical residents, nurses, technicians and public health professionals) during the COVID-19 pandemic in China and explore factors that are associated with the onset of psychological problems in this population during this public health crisis.

METHODS

A cross-sectional, web-based survey was conducted in February 2020 among healthcare workers during the COVID-19 pandemic. Psychological problems were assessed using the Generalized Anxiety Disorder Scale, Patient Health Questionnaire and Insomnia Severity Index. Logistic regression analyses were used to explore the factors that were associated with psychological problems.

RESULTS

The prevalence of symptoms of anxiety, depression, insomnia and the overall psychological problems in healthcare workers during the COVID-19 pandemic in China was 46.04%, 44.37%, 28.75% and 56.59%, respectively. The prevalence of the overall psychological problems in physicians, medical residents, nurses, technicians and public health professionals was 60.35%, 50.82%, 62.02%, 57.54% and 62.40%, respectively. Compared with healthcare workers who did not participate in front-line work, front-line healthcare workers had a higher risk of anxiety, insomnia and overall psychological problems. In addition, attention to negative or neutral information about the pandemic, receiving negative feedback from families and friends who joined front-line work, and unwillingness to join front-line work if given a free choice were three major factors for these psychological problems.

CONCLUSIONS

Psychological problems are pervasive among healthcare workers during the COVID-19 pandemic. Receiving negative information and participating in front-line work appear to be important risk factors for psychological problems. The psychological health of different healthcare workers should be protected during the COVID-19 pandemic with timely interventions and proper information feedback.

Trajectories of maternal symptoms of posttraumatic stress disorder predict long-term mental health of children following the Wenchuan earthquake in China: A 10-year follow-up study

BACKGROUND

Maternal psychopathology can be an important factor associated with psychological adjustment of children. However, there is limited research on long-term impacts of maternal posttraumatic stress disorder (PTSD) on children's mental health. This study examined how PTSD trajectories of women exposed to the 2008 Wenchuan earthquake in China predicted their children's mental health symptoms 10 years after the earthquake.

METHODS

410 dyads of mothers and their adolescent children who exposed to the Wenchuan earthquake were investigated at 12 and 18 months post-earthquake. While the mothers completed measures of earthquake exposure and PTSD symptoms, the children completed measures of earthquake exposure, PTSD, depression and anxiety symptoms. In the 10-year follow up, 257 out of the 410 children completed measures of PTSD, depression and anxiety symptoms. Data were analyzed using linear regression.

RESULTS

Four trajectories of maternal PTSD symptoms were identified: (a) chronic (9.5%); (b) resilient (66.3%); (c) delayed (7.6%); and (d) recovery (16.6%); More importantly, the findings demonstrated that children whose mothers experienced chronic PTSD reported higher level of PTSD and anxiety symptoms 10 years after the earthquake.

LIMITATIONS

Only two waves of maternal PTSD were collected, self-reported tools other than clinical reviews were used to collect data, and a significant proportion of participants did not respond at the 10-year follow-up.

CONCLUSIONS

This study identified maternal PTSD trajectories following the Wenchuan earthquake. Chronic PTSD symptoms in mothers were associated with increased risk of children's PTSD and anxiety 10 years after the earthquake.

Depression of persons with dementia and family caregiver burden: Finding positives in caregiving as a moderator

AIM

The present study examined the association between depression of persons with dementia and family caregiver burden, as well as whether the association depended on the level of caregivers' ability to find positives in caregiving.

METHODS

Based on the medical records of a local mental health hospital and the statistics of an epidemiological survey, this cross-sectional study included 157 major family caregivers of non-institutionalized dementia patients in the rural sector of Western China's Sichuan Province. They responded to the Cornell Scale for Depression in Dementia, a short version of the Zarit Burden Interview, a subscale of a caregiver meaning scale and demographic questions.

RESULTS

Controlling for the demographic variables of the caregivers, the present study found that dementia patients' depression level was significantly associated with caregiver burden (P < 0.001), and the caregivers' levels of finding positives in caregiving significantly moderated the association (P < 0.05). Furthermore, the positive correlation between dementia patients' depression and caregiver burden was weaker among the family caregivers with a high level of finding positives in caregiving, compared with those with a low level of finding positives in caregiving.

CONCLUSIONS

This research suggests the importance of facilitating family caregivers of dementia patients to find positives in caregiving. It provides initial data for the development of dementia caregiver burden interventions that are based on the understanding of the deep meaning of dementia caregiving. Geriatr Gerontol Int 2019; 19: 414-418.

miR-26a suppresses autophagy in swine Sertoli cells by targeting ULK2

A large number of microRNAs (miRNAs) have been detected from porcine testicular tissues thanks to the development of high-throughput sequencing technology. However, the regulatory roles of most identified miRNAs in swine testicular development or spermatogenesis are poorly understood. In our previous study, ULK2 (uncoordinated-51-like kinase 2) was predicted as a target gene of miR-26a. In this study, we aimed to investigate the role of miR-26a in swine Sertoli cell autophagy. The relative expression of miR-26a and ULK2 levels has a significant negative correlation (R²  = .5964, p ≤ .01) in nine developmental stages of swine testicular tissue. Dual-luciferase reporter assay results show that miR-26a directly targets the 3'UTR of the ULK2 gene (position 618-624). In addition, both the mRNA and protein expression of ULK2 were downregulated by miR-26a in swine Sertoli cells. These results indicate that miR-26a targets the ULK2 gene and downregulates its expression in swine Sertoli cells. Based on the expression of marker genes (LC3, p62 and Beclin-1), overexpression of miR-26a or knock-down of ULK2 inhibits swine Sertoli cell autophagy. Taken together, these findings demonstrate that miR-26a suppresses autophagy in swine Sertoli cells by targeting ULK2.

Skeleton labeled 13C-carbon nanoparticles for the imaging and quantification in tumor drainage lymph nodes

Carbon nanoparticles (CNPs) have been widely used in tumor drainage lymph node (TDLN) imaging, drug delivery, photothermal therapy, and so on. However, during the theranostic applications, the accumulation efficiency of CNPs in target organs is unknown yet, which largely hinders the extension of CNPs into clinical uses. Herein, we prepared skeleton-labeled ¹³C-CNPs that had identical properties to commercial CNPs suspension injection (CNSI) for the imaging and quantification in TDLN. ¹³C-CNPs were prepared by arc discharge method, followed by homogenization with polyvinylpyrrolidone. The size distribution and morphology of ¹³C-CNPs were nearly the same as those of CNSI under transmission electron microscope. The hydrodynamic radii of both ¹³C-CNPs and CNSI were similar, too. According to X-ray photoelectron spectroscopy and infrared spectroscopy analyses, the chemical compositions and chemical states of elements were also nearly identical for both labeled and commercial forms. The skeleton labeling of ¹³C was reflected by the shift of G-band toward lower frequency in Raman spectra. ¹³C-CNPs showed competitive performance in TDLN imaging, where the three lymph nodes (popliteal lymph node, common iliac artery lymph node, and paraaortic lymph node) were stained black upon the injection into the hind extremity of mice. The direct quantification of ¹³C-CNPs indicated that 877 μg/g of ¹³C-CNPs accumulated in the first station of TDLN (popliteal lymph node). The second station of TDLN (common iliac artery lymph node) had even higher accumulation level (1,062 μg/g), suggesting that ¹³C-CNPs migrated efficiently along lymphatic vessel. The value decreased to 405 μg/g in the third station of TDLN (paraaortic lymph node). Therefore, the ¹³C-CNPs provided quantitative approach to image and quantify CNSI in biological systems. The implication in biomedical applications and biosafety evaluations of CNSI is discussed.

The Relationship between Parenting Styles and Adolescents' Social Anxiety in Migrant Families: A Study in Guangdong, China

Previous studies indicated that parenting styles were important influencing factors for the development of children’s well-being. It is known that mass migration to the cities in China will affect family relations. However, few studies focused on the relationship between parenting styles and adolescents’ mental health in migrant families. Thus, this study aimed to investigate how parenting styles could affect adolescent’s social anxiety in migrant families. A total number of 1,345 adolescents in migrant families from four non-government-funded junior middle schools in Guangdong province formed the research sample. Parenting styles were measured using short-form of the Egna Minnen Beträffande Uppfostran, and social anxiety was evaluated using Social Anxiety Subscale of Self-Consciousness Scale. The results showed that emotional warmth, overprotection and rejection were significantly more often perceived from mothers than from fathers. Significant group differences between high social anxiety group and low social anxiety group were found in both father’s rearing styles and mother’s rearing styles. Furthermore, in migrant families, paternal emotional warmth could decrease adolescents’ social anxiety, whereas maternal overprotection could increase it.

Families and family therapy in Hong Kong

Family therapy views humans not as separate entities, but as embedded in a network of relationships, highlighting the reciprocal influences of one's behaviours on one another. This article gives an overview of family demographics and the implementation of family therapy in Hong Kong. We start with a review of the family demographics in Hong Kong and brief notes on families in mainland China. Demographics show that the landscape has changed markedly in the past decade, with more cross-border marriages, an increased divorce rate, and an ageing overall population - all of which could mean that there is increasing demand for professional family therapy interventions. However, only a limited number of professionals are practising the systems-based approach in Hong Kong. Some possible reasons as to why family therapy is not well disseminated and practised are discussed. These reasons include a lack of mental health policy to support family therapy, a lack of systematic family therapy training, and a shortage of skilled professionals. Furthermore, challenges in applying the western model in Chinese culture are also outlined. We conclude that more future research is warranted to investigate how family therapy can be adapted for Chinese families.

P01-297-Clinical characteristics of pediatric patients with bipolar disorders in china

Objective

To explore the clinical characteristics, assessment, biological and psychosocial correlates, and treatment of pediatric bipolar disorder (BD) in China.

Method

All the studies published during the past 20 years on pediatric bipolar disorder in China were reviewed.

Results

There is a lack of a unified diagnosis system in China. A serial of genetic researches showed the family aggregation and genetic predisposition of BD. There are consistent findings on the core symptoms of the disorder. BD has the characteristic of comorbidity with other disorders such as ADHD and OCD. Mood stabilizers and combined use of antipsychotics and TCA are still the main choice of psychiatrists to treat the pediatric patients with BD. The effectiveness of specific psychotherapy does need further studies.

Conclusion

A unified diagnosis system and criteria of BD for different age groups is crucial for further work. Combination of various treatments, such as mood stabilizers, AC, TCA and traditional Chinese medicine is effective for these patients. More studies, especially randomized controlled trials should be conducted to explore the etiology, pharmacotherapy and psychotherapy of this disease.

Natural course of schizophrenia: 2-year follow-up study in a rural Chinese community

BACKGROUND

A number of studies have questioned whether the natural course of schizophrenia is more favourable in "developing" than "developed" societies and whether culture is a factor in producing a favourable course.

AIMS

This prospective study tests the hypothesis that the natural outcome of schizophrenia would be favourable in a Chinese rural area.

METHOD

We investigated all patients with schizophrenia, including patients who had not received any treatment, among 149 231 rural community population in Xinjin County, Sichuan in 1994. Those patients who had never received treatment were followed up for two years.

RESULTS

Three-quarters of patients with schizophrenia who had not been treated remained symptomatic. As the duration of illness increased, the illness became more serious. The clinical outcome of the drug-treatment group was significantly better than for patients who had not received any treatment.

CONCLUSIONS

The natural clinical outcome of schizophrenia in the Chinese rural community was poor, and occupational functioning of patients with schizophrenia was comparatively better. Schizophrenia itself has a specific natural course--antipsychotic drug treatment and psychosocial treatment will produce an improvement in prognosis.

GCP-2-induced internalization of IL-8 receptors: hierarchical relationships between GCP-2 and other ELR(+)-CXC chemokines and mechanisms regulating CXCR2 internalization and recycling

The chemotactic potencies of ELR(+)-CXC chemokines during acute inflammation are regulated by their binding affinities and by their ability to activate, desensitize, and internalize their specific receptors, CXCR1 and CXCR2. To gain insight into the fine mechanisms that control acute inflammatory processes, we have focused in this study on the highly potent ELR(+)-CXC chemokine Granulocyte Chemotactic Protein 2 (GCP-2), and on its ability to control the cell surface expression of CXCR1 and CXCR2. Although GCP-2 has been considered an effective ligand for both CXCR1 and CXCR2, our findings demonstrated that it was a potent inducer of CXCR2 internalization only. A functional hierarchy was shown to exist between GCP-2 and 2 other ELR(+)-CXC chemokines, IL-8 and NAP-2, in their abilities to induce CXCR1 and CXCR2 internalization, according to the following: IL-8 > GCP-2 > NAP-2. By the use of pertussis toxin (PTx), it was demonstrated that the actual events of G(alphai)-coupling to CXCR2 do not have a major role in the regulation of its internalization. Rather, CXCR2 internalization was shown to be negatively controlled by induction of signaling events, as indicated by the promotion of CXCR2 internalization following exposure to wortmannin, a potent inhibitor of phosphatidylinositol (PI) 3 kinases and PI4 kinases. Furthermore, our results suggest that rab11(+)-endosomes participate in the trafficking of CXCR2 through the endocytic pathway, to eventually allow its recycling back to the plasma membrane. To conclude, our findings shed light on the interrelationships between GCP-2 and other ELR(+)-CXC chemokines, and determine the mechanisms involved in the regulation of GCP-2-induced internalization and recycling of CXCR2. (Blood. 2000;95:1551-1559)

Differential modes of regulation of cxc chemokine-induced internalization and recycling of human CXCR1 and CXCR2

Studies of human neutrophil IL-8 receptors, CXCR1 and CXCR2, have shown that the two receptors are differentially regulated by ELR(+)-CXC chemokines, that they differ functionally and may have diverse roles in mediating the inflammatory process. To elucidate the role of CXCR1 and CXCR2 in inflammation and to delineate the basis for the divergent regulation of these receptors by IL-8 and NAP-2, we characterized the IL-8- and NAP-2-induced mechanisms regulating the expression of each receptor, focusing on receptor internalization and recycling. Using HEK 293 cell transfectants, IL-8 was shown to induce significantly higher levels of CXCR2 internalization than NAP-2. Moreover, although CXCR2 bound IL-8 and NAP-2 with similarly high affinity, IL-8 functionally competed with and displaced NAP-2, and prompted high levels of internalization, similar to those induced by IL-8 alone. In a system providing an identical cellular milieu for reliable comparisons between CXCR1 and CXCR2, we have shown that the mechanisms controlling the internalization of CXCR1 diverge from those regulating CXCR2 internalization. Whereas IL-8-induced internalization of CXCR1 was profoundly dependent on a region of the carboxyl terminus expressing six phosphorylation sites, internalization of CXCR2 was primarily regulated by a membrane proximal domain of the carboxyl terminus that does not express phosphorylation sites. Analysis of receptor re-expression on the plasma membrane indicated that at early time points following removal of free ligand and incubation of the cells at 37 degrees C, receptor recycling accounted for recovery of CXCR1 and CXCR2 expression, whereas at later time points other processes may be involved in receptor re-expression. Phosphorylation-independent mechanisms were shown to direct both receptors to the recycling pathway. The differential control of CXCR1 vs CXCR2 internalization by IL-8 and NAP-2, as well as by phosphorylation-mediated mechanisms, suggests that a chemokine- and receptor-specific mode of regulation of internalization may contribute to the divergent activities of these receptors.

The in vivo enhancement of IL-1alpha receptor expression on polyoma virus transformed tumor derived cells

The aim of this study was to evaluate expression of receptor for IL-1 on tumor-derived cells. The in vivo acquisition of an expression of a receptor for Fc ç immunoglobulin on polyoma virus transformed cells has been established by us. We investigated whether a receptor for the IL-1 cytokine, like that for Fc gamma immunoglobulin, could also contribute to the heterogeneity of tumor cell population, as well as to its tumorigenic phenotype. Various clones of polyoma virus transformed 3T3 cells were passaged once in syngeneic mice and resulting tumors explanted and recultured. The expression of receptor for IL-1 was tested on in vitro maintained clones (designated C for culture) and on tumor derived clones (designated CTC - culture-tumor-culture). Expression was determined using a 125I radiolabeled ligand and confirmed by flow cytometry with anti-mouse IL-1 receptor (IL-1R) antibodies. Some CTC clones expressed a higher level of IL-1 receptor than others. A positive correlation between the level of IL-1R and a metastatic phenotype was established with some tumor derived cells. A high IL-1R expressing tumor cell population, sorted by flow cytometry, was considerably more metastatic than the sorted low IL-1 expressing cells. IL-1R expression by tumor derived cells may, contribute to the metastatic phenotype of a tumor cell population.

The tumorigenic phenotype of a mutated form of Fc gamma RIIB1, lacking the ability to generate soluble receptor and allowing a low-level of ligand binding

Non immunohematopoietic murine tumor cells ectopically expressing Fc gamma RIIB1 (B1) were recently shown to express a higher tumorigenicity phenotype than cells not expressing this receptor. Utilizing a genetic approach we studied the possible contribution of a soluble form of B1 to tumor enhancement. A mutated form of the B1, lacking the cleavage site responsible for the generation of soluble B1 was produced using gene splicing by overlap extension PCR. A deletion confirmed by sequence analysis from 172 to 178 residues was generated. Stable transfectants expressed the B1 deleted form (B1 Delta) both as specific RNA and as a membrane protein receptor allowing a low level of ligand binding. The soluble form of B1 was undetectable in tissue culture supernatants of Bib transfected cells while it was present in supernatants of wild type B1-transfectants. Stable B1 Delta transfectants were significantly more tumorigenic than negative control transfectants. Tumor incidence was almost as high as that of intact B1 and lagged in the latency period before the appearance of palpable tumors. It is suggested that the soluble B1 has a minimal contribution to tumor enhancement.

Contribution of the intracellular domain of murine Fc-gamma receptor type IIB1 to its tumor-enhancing potential

We have previously shown that Fc gamma receptor type II B1 (Fc(gamma)RIIB1), when expressed on non-lymphoid tumor cells, significantly enhanced their tumorigenic phenotype. This study elucidates the role of the intracellular domain of Fc(gamma)RIIB1 in the enhancement of the malignant phenotype of polyoma-transformed 3T3 cells. We investigated the tumorigenic potential conferred by different variants of the receptor: Fc(gamma)RIIB1, a full-length receptor (B1) whose intracellular region is encoded by exons 8, 9 and 10; Fc(gamma)RIIB2, a spliced variant (B2) whose cytoplasmic domain comprises exons 9 and 10 and lacks exon 8; and Fc(gamma)RIIB1-CT53, a deleted mutant whose cytoplasmic domain contains the fragment encoded by exon 8 alone. We have investigated various properties of cells transfected with each of the above variants: tumorigenicity in syngeneic mice, formation of colonies in soft agar, growth rate, production of soluble receptor and capping of the ligand-bound receptor. Results show that while the presence of exon 8 did not enhance growth rate in vitro or production of soluble Fc(gamma)R, it did enhance the tumorigenic phenotype of transfected cells (both in vivo and in vitro growth in soft agar). B1-expressing cells exhibited a significantly higher tumorigenic phenotype than B2 cells. The presence of exon 8 alone (CT53 mutant) conferred the transfected cells a higher tumorigenic phenotype than Fc(gamma)R-negative control cells but lower than intact B1 or B2 cells, indicating that the presence of B1-specific exon 8 is not sufficient but that the presence of an intact B1 intracellular domain is essential, for conferring the high tumorigenicity phenotype upon cells. We conclude that the capping, following ligand binding contributed by exon 8, and the function contributed by the specific localization of exons 9 and 10 in B1 cells may determine their malignant phenotype.

The murine Fc-gamma (Fc gamma) receptor type II B1 is a tumorigenicity-enhancing factor in polyoma-virus-transformed 3T3 cells

The murine receptor for the Fc portion of IgG is a molecule expressed by cells of the immune system. This study suggests the hypothesis that Fc gamma receptor type II B I (Fc gamma RIIB I) functions as a progression-enhancing factor when expressed ectopically on non-lymphoid tumor cells. It has been shown previously that BALB/c 3T3 cells transformed in vitro with polyoma virus (PyV) do not express Fc gamma RII but acquire the expression of this receptor following an in vivo passage in syngeneic mice. The specific Fc gamma RII transcript present in tumor cells was identified in this report as Fc gamma RIIB I (BI). In order to determine whether or not the ectopically expressed Fc gamma RII plays a role in the progression of these transformed cells, PyV-transformed 3T3 cells were transfected with BI-cDNA. The BI transfected cells were tested for their ability to form local tumors in syngeneic mice, as compared to transfected cells which express the co-transfecting neomycine resistance (neores) DNA alone or together with the lacZ gene. Fc gamma RIIB I expressors exhibited a significantly higher tumorigenic phenotype than FcR-negative controls, though both types of cells exhibited the same growth curve in vitro. The ability of Fc gamma RIIB I to act as a potentially tumorgenicity-enhancing factor was also demonstrated as Fc gamma RII was expressed by tumor cells, originating from inoculated Fc gamma RIIB I-transfected cells, or from inoculation of a mixture of receptor-positive and -negative cells. B I-expressing cells dominated the tumor-cell population over non-expressors. This dominance strengthened the hypothesis that FcR plays a role in tumor progression in vivo.

A controlled evaluation of psychoeducational family intervention in a rural Chinese community

BACKGROUND

The shortage of mental health care in rural China might be tackled by community care. This study tests the hypothesis that family intervention increases patients' treatment compliance, which is crucial in community care.

METHOD

A cohort of psychiatric patients were randomly selected to a controlled trial for four months. Compliance rates, clinical and social outcomes were measured double-blindly.

RESULTS

The compliance rate was increased significantly in the trial group, and they had better clinical and social outcomes.

CONCLUSIONS

Family intervention is an effective method of improving treatment compliance and should be an important part of community mental health care.

FcR may function as a progression factor of nonlymphoid tumors

Tumor progression is a multistep process involving genetic and epigenetic changes in a transformed clone. Some of these changes may be induced by host factors which may also select for transformed cellular variants with a high ability to survive and propagate. In this article we review studies showing that receptors for the Fc portion of IgG may be expressed on cells from human or animal tumors of nonlymphoid origin. We also review data demonstrating that at least with respect to cells transformed in vitro with Polyoma virus, transformation per se is not sufficient for the induction of Fc receptor expression. We also summarize preliminary data showing that Fc receptor expression is causally involved in conferring a high malignancy phenotype upon transformed cells. Possible mechanisms to explain these observations are discussed.

Possibilities of interference with the immune system of tumor bearers by non-lymphoid Fc gamma RII expressing tumor cells

The ectopic expression of Fc gamma RII by PyV transformed 3T3 cells derived from tumors of long latency has been established. It was suggested that this expression is one of several changes conferring upon the cells an increased capacity for survival. We found that in one case cells expressing a very high level of Fc gamma RII had also a very high metastatic phenotype as compared to FcR negative cells. Direct evidence that Fc gamma RIIbl functions as a progression factor was provided by transfection experiments. The transfected gene conferred an increased malignancy and invasive phenotype upon PyV or c-Ha-ras transformed cells. In the present study we tested the possibility that Fc gamma RII expressing tumor cells could interfere with the immune system. The following subjects were investigated: 1) The ability of Fc gamma R on the tumor cells to bind the ligand and/or release IBF. 2) The effect of a local accumulation of ligand and/or IBF (assumed to take place in situ in the tumor) on Fc gamma RII expressing T cells. It was found that both tumor-derived receptor positive and beta l transfected PyV transformed cells were capable of binding aggregated mouse IgG. The binding of bivalent ligand was followed by an increase in membrane Fc gamma RII expression. Also both types of cells were capable of releasing IBF. We then tested the possibility that a local accumulation of IgG within the tumor could effect Fc gamma R expressing T cells. It was found that aggregated mouse IgG (as well as IgGl) could stimulate the proliferation of the T cell hybridoma (T2D4) and other Fc gamma RII expressing T cells. We also found that the expression of beta Fc gamma RII specific mRNA peaked at the logarithmic phase of T2D4 cultures, in parallel with their maximal potential to release IBF. Several pathways for interference with the immune system are suggested.

Phenotypic properties of 3T3 cells transformed in vitro with polyoma virus and passaged once in syngeneic animals

Cloned BALB/c 3T3 cells transformed in vitro with polyoma virus (PyV) acquired a higher tumorigenicity phenotype after a single in vivo passage. Some of the in vivo passaged cells (CTC cells) exhibited also a higher metastatic phenotype than cells from the same clones that were maintained only in culture (C cells). A phenotypic comparison between CTC and C cells was performed. It was found that most CTC lines exhibited a higher binding to laminin compared to their clonal C cell ancestors. Some CTC cells were less sensitive to the cytotoxic effects of TNF-alpha than the corresponding C cells. CTC cells originating from tumors which appeared after a long latency period (late tumors) tended to express Fc gamma RII while CTC cells originating from tumors which appeared after a short latency period (early tumors) as well as the corresponding C cells tended not to express Fc gamma RII. The expression of a membrane epitope recognized by a monoclonal antibody expressing specificity towards PyV transformed cells, was down-regulated on late tumor cells compared to early tumor cells. Transfection of cloned PyV-transformed BALB/c 3T3 cells with the beta 1Fc gamma RII gene augmented the tumorigenicity and metastatic phenotype of the transfectants compared to control transfectants.

In vivo acquisition of Fc gamma RII expression on polyoma virus-transformed cells derived from tumors of long latency

BALB/c 3T3 cells transformed in vitro with polyoma virus were cloned and passaged once in syngeneic mice. Resulting tumors from each clone were explanted and recultured. Expression of receptor for Fc of IgG (Fc gamma RII) in the original in vitro maintained clones and in cells derived from tumors elicited by the respective cells was measured at the protein level as well as at the mRNA level. Clones were assayed in pairs. The ancestor in vitro maintained clones [designated cultured cells (C)] were compared with cells derived from the same clones after a single passage in vivo followed by explantation and reculturing [designated cultured-tumor-cultured cells (CTC)]. C cells of any of the tested clones did not express Fc gamma RII. On the other hand, certain CTC cells were positive. The Fc gamma RII-positive cells were derived from tumors appearing after a long precancer latency period (greater than 140 days). CTC cells derived from tumors that appeared after shorter latency periods (less than 80 days) were Fc gamma RII negative. These results were obtained both by using radioimmunoassay and monoclonal antibodies against mouse Fc gamma RII as well as by Northern blot analysis using the Fc gamma RII complementary DNA probe. The involvement of macrophages as the Fc gamma RII-expressing cells in CTC cells was excluded. Fc gamma RII expression was down-regulated in CTC cells as a function of time following their explantation into culture. Fc gamma RII expression could be up-regulated in these cells and induced on C cells by maintaining the cultured cells in the presence of normal mouse serum or recombinant interferon. We also tested the expression of Fc gamma RII on CTC cells following their inoculation into syngeneic mice for a second time (CTCx2 cells). The results showed a positive correlation between Fc gamma RII expression in the inoculated ancestor CTC cells and on the CTCx2 cell progeny.

Some cellular and molecular characteristics of high and low tumorigenicity variants of polyoma-virus transformed cells

We analyzed several cellular and molecular properties of BALB/c 3T3 cellular clones transformed in vitro with polyoma virus and exhibiting a high or low tumorigenicity phenotype. We also analyzed the same clones after a single in vivo passage in syngeneic mice. This passage invariably induced and/or selected variants exhibiting a very high tumorigenicity phenotype. BALB/c mice bearing tumors induced by the inoculation of the above cells, regardless of their tumorigenicity phenotype, have a lower number of L3T4 positive splenocytes than appropriate controls. The response to Con-A of spleen cells from such mice was also suppressed. Concomitantly, an increase in Mac-1 positive splenocytes could be measured. In spite of the non-specific suppression of T cells, spleen cells from tumor-bearers showed a specific proliferative response to polyoma antigens. Molecular analysis of polyoma transformed cells showed no differences between the various cells with respect to integration of the polyoma viral genes or with respect to src, myc and fos proto-oncogenes. In vitro maintained cells and in vivo passaged cells seemed to differ, however, in the content of polyoma middle T. Whereas polyoma virus transformed cells maintained only in culture never expressed low affinity receptors for IgG (Fc gamma RII), certain in vivo passaged cells did. This expression could be measured both at the protein and the mRNA level. Those in vivo passaged cells which expressed F alpha RII gave tumors following a long latency period. Ongoing experiments will indicate whether or not Fc gamma RII expression is linked to long latency of tumor development.

Increased expression of Fc gamma receptor in cancer patients and tumor bearing mice

In this study we report on some lines of ongoing research performed in our laboratory, in relation to the increased expression of FcR on tumor cells, as well as on cells present in the tumor-bearing host, and its possible role in tumor progression. In a previous study we have shown that a Polyoma virus (PyV)-induced anaplastic carcinoma (SEYF-a tumor) contained an FcR-expressing subpopulation of tumorigenic cells. We tested the effect of in vivo passaging of FcR-expressing and of non-FcR-expressing sub-populations of SEYF-a tumor cells on the expression of FcR, as revealed by the ability of these cells to bind the 2.4G2 monoclonal antibody, which is directed against mouse Fc gamma 2b/gamma 1R. It was found that upon in vivo passaging these two sub-populations became practically identical in their ability to bind anti-Fc gamma R antibody. On the other hand, in vitro passaging of FcR-expressing SEYF-a cells resulted in a gradual decrease in the expression of Fc gamma R. These results, indicating that the expression of Fc gamma R on tumor cells, per se, is dependent on a factor present in the in vivo environment were confirmed using 3T3 cells transformed in vitro by PyV (C) and forming tumors at first injection to mice (CTC). C cultures of various clones did not express Fc gamma R, while CTC cultures (cultures from tumors) became positive. We also detected an increase in the level of a soluble form of Fc gamma 2b/gamma 1R in the circulation of mice bearing PyV induced tumors. This increase paralleled the appearance of palpable tumors. A similar pattern of increase was observed in mice inoculated with the c-H-ras transformed tumorigenic clone 8/F/5, but not in mice inoculated with non-tumorigenic 3T3 cells. Data published by us show that metastatic breast cancer patients had significantly elevated Fc gamma R levels on their peripheral blood mononuclear cells (PBMC). Experiments presented here indicate a direct correlation between increased Fc gamma R levels on PBMC and tumor mass in colon, ovary and lung metastatic carcinoma patients. The possibility that malignantly transformed cells have the potential to cause proliferation of Fc gamma R expressing T cells was tested. It was found that extract derived from r-H-ras transformed 3T3 cells triggers the proliferation of a T cell hybridoma expressing Fc gamma R.

Correlation of Fc gamma receptors on peripheral blood mononuclear cells and survival in patients with metastatic breast cancer

Patients with carcinomas have elevated levels of Fc receptors for IgG (Fc gamma R) on their peripheral blood mononuclear cells (PBMC). The purpose of the present study was to determine whether there is a correlation between Fc gamma R levels on PBMC and survival in patients with metastatic breast cancer. Binding assays were performed on PBMC using 125I-labeled fibrinogen complexed with rabbit IgG (or as a control F(ab')2) anti-human fibrinogen. Twenty-two metastatic breast cancer patients had significantly (p less than 0.001) elevated Fc gamma R levels as compared to either 22 breast cancer patients receiving adjuvant chemotherapy following mastectomy without clinical evidence of tumor, or to 34 non-malignant controls. Significantly more metastatic patients with elevated Fc gamma R levels died at 6 months (p less than 0.001) as compared to those with low levels. A direct correlation between Fc gamma R levels and hazard probability was found (correlation coefficient = 0.3321, p less than 0.005). These results raise the possibility that Fc gamma R levels on PBMC from metastatic breast cancer patients may be clinically useful as a prognostic marker of disease activity.

Expression of Fc gamma receptors on a subpopulation of nonlymphoid tumor cells and its enrichment

Nonadherent Fc gamma receptors (Fc gamma R) expressing cells from SEYF-a tumors that form rosettes with sheep erythrocytes coated with IgG antibodies (EA) were isolated by Percoll density gradients. The EA-IgG rosette-forming cells were characterized by the parameters of 1) binding of IgG immune complexes; 2) binding of purified monoclonal antibodies against mouse FcR; 3) sensitivity to complement-dependent lysis mediated by syngeneic anti-SEYF-a antibodies; 4) expression of parental H-2 antigen when grown in F1 hybrids; 5) incorporation of [125I]5-iodo-2'-deoxyuridine; and 6) growth in syngeneic mice. The nonadherent EA-IgG rosette-forming cell population was found to be composed of both host lymphocytes as well as of tumor cells. Tumor-seeking lymphocytes then were removed from SEYF-a tumors by velocity sedimentation on Percoll. The remaining cell population was tumorigenic and expressed FcR, as well as tumor antigens. These tumor EA-IgG rosette-forming cells exhibited a very low rate of DNA synthesis compared with that of non-rosetting tumor cells.

Circulating cellfree Fc gamma 2b/gamma 1 receptor in normal mouse serum: its detection and specificity

By using intact or Fab fragments of rat monoclonal antibodies against murine Fc gamma 2b/gamma 1 receptor, in a solid phase radioimmunoassay, we demonstrated the occurrence of circulating cellfree Fc gamma 2b/gamma 1 receptors (Cf-Fc gamma 2b/gamma 1R) in normal mouse serum. These Cf-Fc gamma 2b/gamma 1R were removed from serum by affinity chromatography by using Sepharose columns coupled with IgG but not by Sepharose coupled with F(ab')2 fragments. Furthermore, the material retained by and eluted from the Sepharose IgG column reacted with the monoclonal antibody; these results support a direct relationship between the antigenic and the functional Cf-Fc gamma 2b/gamma 1R that were detected in serum. This Cf-Fc gamma 2b/gamma 1R was found in all the 39 normal mouse sera that were tested. The results seemed to indicate that aging may be associated with increased levels of Cf-Fc gamma 2b/gamma 1R and that levels of circulating Fc gamma R may be under genetic regulation. By forming complexes with circulating IgG within the blood stream, such Cf-Fc gamma 2b/gamma 1R may modulate some of the functions in which the Fc portion of Ig is involved.

Circulating cellfree Fc gamma 2b/gamma 1 receptor in normal mouse serum: its detection and specificity

By using intact or Fab fragments of rat monoclonal antibodies against murine Fc gamma 2b/gamma 1 receptor, in a solid phase radioimmunoassay, we demonstrated the occurrence of circulating cellfree Fc gamma 2b/gamma 1 receptors (Cf-Fc gamma 2b/gamma 1R) in normal mouse serum. These Cf-Fc gamma 2b/gamma 1R were removed from serum by affinity chromatography by using Sepharose columns coupled with IgG but not by Sepharose coupled with F(ab')2 fragments. Furthermore, the material retained by and eluted from the Sepharose IgG column reacted with the monoclonal antibody; these results support a direct relationship between the antigenic and the functional Cf-Fc gamma 2b/gamma 1R that were detected in serum. This Cf-Fc gamma 2b/gamma 1R was found in all the 39 normal mouse sera that were tested. The results seemed to indicate that aging may be associated with increased levels of Cf-Fc gamma 2b/gamma 1R and that levels of circulating Fc gamma R may be under genetic regulation. By forming complexes with circulating IgG within the blood stream, such Cf-Fc gamma 2b/gamma 1R may modulate some of the functions in which the Fc portion of Ig is involved.

A radioimmunoassay with monoclonal antibodies for the detection of antigenic cell-free Fc receptor

Making use of 125I-labelled monoclonal rat antibodies against mouse Fc receptor we have developed a solid-phase radioimmunoassay for cell-free antigenic mouse Fc receptor (FcR). An 80% acetone solution was used for fixation of relatively large amounts of soluble proteins on PVC microtiter plates. As a result of this treatment FcR practically lost its activity to bind the Fc portion of an IgG molecule but retained its antigenicity, the binding of specific anti-FcR (aFcR) antibody being increased following acetone fixation. Concentrations of cell-free FcR in NP-40 extracts of FcR-expressing cells were calculated from the linear part of a standard curve and expressed in units of antigenic activity, 1 unit being the amount of antigenic FcR capable of binding 1 microgram of 125I-aFcR. The method may be used for detecting cell-free FcR as a minor constituent in a mixture of proteins.

Studies on the level of natural antibodies reactive with various tumor cells during urethane carcinogenesis in BALB/c mice

Serum from young normal BALB/c mice was found to contain IgM antibodies able to mediate complement-dependent lysis of certain syngeneic or allogeneic tumor target cells. The titer of such naturally occurring antitumor antibodies ( NATA ) was found to increase with aging. A longitudinal serological study comparing the cytotoxicity potential of NATA from normal and from urethan-treated BALB/c mice was performed. It was found that urethan-treated mice that did not develop primary lung-adenomas within the duration of the experiment had significantly lower NATA titers, against one out of 4 target cells assayed, than urethan-treated animals that developed lung adenomas. This difference was evident in two independent experiments. The results suggested that the lower NATA activity of the urethan-treated mice that did not develop tumors existed even before exposure to the carcinogenic insult. This raises the possibility that certain populations could be segregated according to their natural antibody profile into those individuals which will develop primary tumors within a certain period if exposed to a subthreshold amount of carcinogen, and those which will not.