[Characteristics of narrow hypopharynx in patients with catathrenia]

Objective: To analyze whether the upper airway of patients with catathrenia has obstructive manifestations using nasal resistance, craniofacial, and upper airway imaging methods, which could benefit the exploration of the etiology and treatment options. Methods: From August 2012 to September 2019, a total of 57 patients with catathrenia in the Department of Orthodontics at Peking University Hospital of Stomatology were included in the study, including 22 males and 35 females, aged (31.1±10.9) years, with a body mass index of (21.7±2.7) kg/m². All the patients were diagnosed by full-night polysomnography at the Sleep Division, Peking University People's Hospital, of which 10 patients were combined with obstructive sleep apnea hypopnea syndrome (OSAHS). The median groaning index of patients was 4.8 (1.8, 13) events/h. Nasal resistance and cone-beam CT were conducted on the patients, and measurements were performed on the craniofacial structures, upper airway, and surrounding soft tissues, compared with non-snoring normal occlusion individuals' references published by the same research team (144 college students recruited at Peking University and 100 non-snoring young adults with normal occlusion recruited at six universities in Beijing). Results: The total nasal resistance of patients with catathrenia was (0.26±0.08) Pa·cm^-3·s^-1. The patients had overall well-developed mandibular hard tissues. However, the patients were found with increased FH/BaN (steep anterior cranial base plane), increased MP/FH (forward rotation of the mandible); increased U1/NA and L1/MP (proclined upper and lower incisors). The sagittal diameter of the velopharynx [(19.2±4.5) mm] was significantly larger than the normal reference (t=8.44, P<0.001), while the sagittal diameter at the hypopharynx [(17.4±6.4) mm] was statistically smaller than the normal reference (t=-2.79, P=0.006). Catarhrenia patients combined with OSAHS presented longer soft palate, tongue, and lower hyoid bone than those with primary catathrenia. Conclusions: In patients with catathrenia, the overall craniofacial characteristics are well-developed skeletal structures, lower nasal resistance, proclined upper and lower incisors, wide upper sagittal development of the upper airway and but narrow hypopharynx. Groaning sounds might be related to the narrowing of the hypopharynx during sleep.

[Relationship of diffusion kurtosis imaging parameters with the pathologic type and prognosis of rectal tumors]

Objective: To explore the application value of diffusion kurtosis imaging (DKI) in the differential diagnosis of rectal tumors and evaluating the prognostic factors associated with rectal adenocarcinoma. Methods: A total of 105 patients with rectal tumors admitted in the First Affiliated Hospital of Zhengzhou University from December 2018 to August 2020 were retrospectively analyzed. All patients underwent high-resolution magnetic resonance DKI scanning. The mean diffusivity (MD), mean kurtosis (MK) and apparent diffusion coefficient (ADC) were measured and the relationship of these parameters with pathological types and prognostic factors of rectal tumor were analyzed. The diagnostic efficacy of MD, MK, and ADC for positive circumferential resection margin (CRM) and extramural venous invasion (EMVI) of rectal adenocarcinoma was evaluated by the receiver operating characteristic (ROC) curve. Results: MD and ADC were only related to pathological type. The MD and ADC were (2.091±0.390)×10(-3) and (1.478±0.265)×10(-3) mm(2)/s in mucinous adenocarcinoma, higher than (1.136±0.182)×10(-3) and (0.767±0.077)×10(-3) mm(2)/s in unspecified adenocarcinoma and (1.617±0.697)×10(-3) and (0.940±0.179)×10(-3) mm(2)/s in tubulo-villous adenoma. The MD and ADC in unspecified adenocarcinoma were lower than those in tubule-villous adenoma (P<0.05). Nevertheless, MK was associated with pathological type, N stage, CRM and EMVI. The MK was 0.566±0.110 in mucinous adenocarcinoma, lower than 0.982±0.135 in unspecified adenocarcinoma and 0.827±0.121 in tubulo-villous adenoma. The MK in unspecified adenocarcinoma was higher than that in intubulo-villous adenoma. The MK was 0.984±0.107 in pN1-2, higher than 0.881±0.146 in pN0. The MK was 0.990±0.142 in positive CRM, higher than 0.862±0.114 in negative CRM. The MK was 0.996±0.140 in positive EMVI, higher than 0.832±0.100 in negative EMVI (P<0.05). The ROC curves showed that the AUCs of MD, MK and ADC in diagnosing positive CRM were 0.459, 0.653 and 0.408, respectively; with MK=1.006 as the optimal diagnostic threshold, the diagnostic sensitivity and specificity were 51.9% and 81.0%, respectively. The AUCs of MD, MK and ADC values in diagnosing positive EMVI were 0.510, 0.662 and 0.388, respectively; with MK=1.010 as the optimal diagnostic threshold, the diagnostic sensitivity and specificity were 50.9% and 87.5%, respectively. Conclusions: DKI quantitative parameter is helpful for discriminating rectal tubulo-villous adenoma, unspecified adenocarcinoma, and mucinous adenocarcinoma, and is helpful for predicting the prognosis of patients with rectal adenocarcinoma. High MK is associated with positive CRM and EMVI.

Strategies for screening, occupational prevention, and management of COVID-19 in outpatient clinics in Shandong

Objective

We hope to analyze the information of outpatients in a tertiary care hospital during the epidemic of COVID-19, so as to formulate effective regulations for the prevention and control of COVID-19.

Methods

We collected information from outpatients from January 28, 2020 to March 2, 2020 and performed the statistical analysis.

Results

During the study period, there were more than 60,000 outpatients. Among them, 404 patients with a body temperature above 37.3°C who had not been to Wuhan and had no contact with people from Wuhan. There were 8 people who had contact with people from Wuhan, such as 4 people with fever, 3 people with normal body temperature but cough symptoms, and 1 person with normal body temperature and no other discomfort. There were 2 patients with high body temperature from the epidemic area in Wuhan, and one novel Coronavirus patient was confirmed as the final result.

Conclusion

During the COVID-19 pandemic, outpatient medical staff should enhance their awareness of protection, hospitals should standardize the outpatient COVID-19 prevention and control system, improve the prevention and emergency system, and reduce occupational exposure hazards and the occurrence of post-exposure infections.

[Clinical characteristics of 272 437 patients with different histopathological subtypes of primary esophageal malignant tumors]

Objective: To characterize the histopathological subtypes and their clinicopathological parameters of gender and onset age by common, rare and sparse primary esophageal malignant tumors (PEMT). Methods: A total of 272 437 patients with PEMT were enrolled in this study, and all of the patients were received radical surgery. The clinicopathological information of the patients was obtained from the database established by the State Key Laboratory of Esophageal Cancer Prevention & Treatment from September 1973 to December 2020, which included the clinical treatment, pathological diagnosis and follow-up information of esophagus and gastric cardia cancers. All patients were diagnosed and classified by the criteria of esophageal tumor histopathological diagnosis and classification (2019) of the World Health Organization (WHO). The esophageal tumors, which were not included in the WHO classification, were analyzed separately according to the postoperative pathological diagnosis. The χ² test was performed by the SPSS 25.0 software on count data, and the test standard α=0.05. Results: A total of 32 histopathological types were identified in the enrolled PEMT patients, of which 10 subtypes were not included in the WHO classification. According to the frequency, PEMT were divided into common (esophageal squamous cell carcinoma, ESCC, accounting for 97.1%), rare (esophageal adenocarcinoma, EAC, accounting for 2.3%) and sparse (mainly esophageal small cell carcinoma, malignant melanoma, etc., accounting for 0.6%). All the common, rare, and sparse types occurred predominantly in male patients, and the gender difference of rare type was most significant (EAC, male∶ female, 2.67∶1), followed with common type (ESCC, male∶ female, 1.78∶1) and sparse type (male∶ female, 1.71∶1). The common type (ESCC) mainly occurred in the middle thoracic segment (65.2%), while the rare type (EAC) mainly occurred in the lower thoracic segment (56.8%). Among the sparse type, malignant melanoma and malignant fibrous histiocytoma were both predominantly located in the lower thoracic segment (51.7%, 66.7%), and the others were mainly in the middle thoracic segment. Conclusion: ESCC is the most common type among the 32 histopathological types of PEMT, followed by EAC as the rare type, and esophageal small cell carcinoma and malignant melanoma as the major sparse type, and all of which are mainly occur in male patients. The common type of ESCC mainly occur in the middle thoracic segment, while the rare type of EAC mainly in the lower thoracic segment. The mainly sparse type of malignant melanoma and malignant fibrous histiocytoma predominately occur in the lower thoracic segment, and the remaining sparse types mainly occur in the middle thoracic segment.

[Assessment of MS-Score and HScore in timeliness of diagnosis of macrophage activation syndrome associated with adult-onset Still's disease]

The data of 33 patients with adult-onset still's disease (AOSD)-associated macrophage activation syndrome (MAS) were retrospectively collected from January 2013 to December 2020 in Peking Union Medical College Hospital. Hemophagocytic lymphohistiocytosis (HLH)-2004 criteria, macrophage activation syndrome/juvenile idiopathic arthritis (MS-Score) and hemophagocytic syndrome diagnostic score (HScore) were used to diagnose AOSD-associated MAS, respectively. The time of diagnosis of AOSD-associated MAS by MS-Score was 19.0 (4.5, 31.0) days [M (Q₁,Q₃)] earlier than by HLH-2004 criteria, and 13.5 (0.5, 21.5) days earlier than by HScore (both P<0.05). The difference was not statistically significant between the time of diagnosis of AOSD-associated MAS by Hscore and by HLH-2004 criteria (P>0.05). There was significant difference among the three criteria (P<0.001). MS-Score can be used to diagnose AOSD-associated MAS earlier than HLH-2004 criteria, while the timeliness of HScore is not certain.

[A multicenter, randomized, double-masked, placebo-controlled trial of compound wild chrysanthemum eye masks for mild and moderate dry eye]

Objective: To investigate the clinical efficacy and safety of compound wild chrysanthemum eye masks for mild and moderate dry eye. Methods: In this double-masked, multicenter, placebo-controlled, randomized trial, middle-aged and elderly patients with mild and moderate dry eye were enrolled from six hospitals (Xiamen Eye Center of Xiamen University, China-Japan Friendship Hospital, Peking Union Medical College Hospital, Wangjing Hospital of China Academy of Chinese Medical Sciences, Affiliated Eye Hospital of Shandong University of Traditional Chinese Medicine and Hebei Eye Hospital). The patients were assigned to the compound wild chrysanthemum eye mask group and the eye mask simulator group based on the random number table. Subjective symptoms of dry eye, visual acuity, break-up time (BUT), Schirmer Ⅰ test, and corneal fluorescent staining were evaluated in all patients before treatment and at 1 and 2 weeks after treatment. All adverse reactions during the treatment and follow-up were recorded. Results: A total of 120 patients were enrolled. Among them, 112 subjects were included for statistical analyses after the exclusion of 8 subjects who were lost for follow-up or had an adverse event, with an age of (54.26±7.44) years. All the indicators were equally comparable between the two groups. Before treatment and at 1 and 2 weeks after treatment, the median (lower quartile, upper quartile) of total score of questionnaires in the eye mask group was 14.50 (10.00, 19.00), 9.00 (5.00, 14.00) and 7.00 (4.00, 10.00), respectively, and that in the control group was 14.00 (9.00, 22.50), 12.00 (6.00, 20.00) and 10.00 (3.50, 17.00), respectively. The score decreased significantly in both groups after 1 week (t=9.1604, S=398.00; P<0.01) and 2 weeks (S=681.00, 575.50; P<0.05) of treatment. The total score of questionnaires in the eye mask group was significantly lower than that in the control group (Z=3.27, 2.81; P<0.05) after treatment. After 1 week of treatment, the average BUT of the eye mask group was (5.71±2.31) s, which was significantly longer than that before treatment (5.06±2.00) s (S =208.50, P<0.05). But there was no significant difference in the control group (S=150.00, P>0.05). After 2 weeks of treatment, there was statistically significant difference in BUT between the two groups (S=407.00, t=3.07; P<0.01). After 1 week of the treatment, the amount of tear secretion in the eye mask group [(6.88±4.78) mm] was significantly larger than that before treatment (S=196.50, P<0.05), while the control group [(6.80±5.85) mm] showed no significant difference (S=55.00, P<0.05). After 2 weeks of the treatment, the amount increased significantly to (7.43±4.86) mm and (7.29±4.56) mm, respectively, in both groups (t=-3.29, -2.26; P<0.05). The difference in the average BUT, Schirmer Ⅰ test result and corneal fluorescent staining between both groups was not statistically significant at each time point. Five mild adverse events occurred, including 2 adverse events (2 times, 3.51%) in the eye mask group and 3 adverse events (4 times, 5.36%) in the control group. Conclusions: Compound wild chrysanthemum eye masks can effectively improve the symptoms and physical signs of mild and moderate dry eye and can be used as an auxiliary treatment. (Chin J Ophthalmol, 2021, 57: 601-607).

[Analysis of the first cluster of cases in a family of COVID-19 in Gansu Province]

The epidemiological history and clinical characteristics of 7 cases of COVID-19 and 1 case of close contact in the first family aggregation epidemic of COVID-19 in Gansu Province were analyzed. The first patient A developed on January 22, 2020, with a history of residence in Wuhan, and confirmed severe cases of NCP on January 24, 2020; patient B, on January 23, 2020, diagnosed on January 31, severe cases; patient C, asymptomatic, diagnosed on January 27; patient D, asymptomatic, diagnosed on January 27; patient E, on January 24, diagnosed on January 28; patient F, asymptomatic, diagnosed on January 31; Patient G was asymptomatic and was diagnosed on January 31. In close contact, H was asymptomatic, PCR test was negative and asymptomatic, and he was discharged early. Among the 7 patients, 1 case died of (B) aggravation, and the other patients' condition was effectively controlled after active treatment. Except for the discharged cases, 5 cases were positive for COVID-19 specific IgM antibody and 1 case was negative. In this clustering outbreak, 4 patients remained asymptomatic, but PCR and IgM antibodies were positive, indicating that asymptomatic patients may be the key point to control the epidemic. Specific IgM antibody screening for patients whose pharyngeal swab nucleic acid test is negative but with ground glass-like lung lesions is very important for early detection and early isolation.

[Analysis of the first cluster of cases in a family of novel coronavirus pneumonia in Gansu Province]

The epidemiological history and clinical characteristics of 7 cases of COVID-19 and 1 case of close contact in the first family aggregation epidemic of COVID-19 in Gansu Province were analyzed. The first patient A developed on January 22, 2020, with a history of residence in Wuhan, and confirmed severe cases of NCP on January 24, 2020; patient B, on January 23, 2020, diagnosed on January 31, severe cases; patient C, asymptomatic, diagnosed on January 27; patient D, asymptomatic, diagnosed on January 27; patient E, on January 24, diagnosed on January 28; patient F, asymptomatic, diagnosed on January 31; Patient G was asymptomatic and was diagnosed on January 31. In close contact, H was asymptomatic, PCR test was negative and asymptomatic, and he was discharged early. Among the 7 patients, 1 case died of (B) aggravation, and the other patients' condition was effectively controlled after active treatment. Except for the discharged cases, 5 cases were positive for COVID-19 specific IgM antibody and 1 case was negative. In this clustering outbreak, 4 patients remained asymptomatic, but PCR and IgM antibodies were positive, indicating that asymptomatic patients may be the key point to control the epidemic. Specific IgM antibody screening for patients whose pharyngeal swab nucleic acid test is negative but with ground glass-like lung lesions is very important for early detection and early isolation.

[Anti-myelin-associated glycoprotein antibody positive IgM monoclonal gammopathy related peripheral neuropathy: 11 cases and literature review]

目的

提高对罕见的抗髓鞘相关糖蛋白（MAG）抗体阳性的IgM相关性周围神经病（IgM-PN）的认识。

方法

总结2014年1月至2019年4月北京协和医院诊断的11例抗MAG抗体阳性的IgM-PN患者的临床特点、实验室检查、治疗方案和预后。

结果

11例患者中，男8例，女3例，中位发病年龄63（52~77）岁。其中9例患者以远端肢体麻木起病，6例伴肌力减退。神经传导速度检查示，均为周围神经脱髓鞘损害，以下肢感觉神经损害为主，6例伴慢性轴索损害。11例患者均存在血清IgM型单克隆免疫球蛋白，6例为IgM κ型，3例为IgM λ型，2例为IgM κ/IgG κ双克隆型。3例患者继发于巨球蛋白血症。11例患者的血清抗MAG抗体均为阳性。9例患者接受利妥昔单抗单药或联合化疗，治疗后7例患者的神经症状稳定或改善。

结论

抗MAG抗体阳性的IgM-PN是一种罕见的M蛋白相关性疾病。对于伴IgM型M蛋白的周围神经病患者，应常规筛查抗MAG抗体。基于利妥昔单抗的治疗可作为其一线治疗方案。

Tumor necrosis factor-α-induced protein 8-like 2 mRNA in peripheral blood mononuclear cells is associated with the disease progression of chronic hepatitis B virus infection

BACKGROUND

Tumor necrosis factor-alpha-induced protein 8-like 2 (TIPE2) is a novel target and molecule in the negative regulation of immune homeostasis. The present study aimed to investigate the dynamic expression of TIPE2 mRNA during the progression of chronic hepatitis B virus (HBV) infection.

METHODS

A total of 193 patients with chronic HBV infection were retrospectively recruited into this cross-sectional study, including 97 patients with chronic hepatitis B (CHB), 55 with liver cirrhosis and 41 with HBV-related hepatocellular carcinoma (HCC). TIPE2 mRNA was determined using real-time quantitative polymerase chain reaction.

RESULTS

The expression of TIPE2 levels in patients with HCC was significantly decreased compared with expression in patients with liver cirrhosis, CHB and healthy controls (P < 0.05); meanwhile, the TIPE2 mRNA levels in patients with CHB and liver cirrhosis were significantly increased compared with levels in healthy controls (P < 0.01). In liver cirrhosis, the TIPE2 mRNA level in the decompensated state was significantly higher than that in the compensated state (P < 0.05). In HCC patients, TIPE2 mRNA was significantly associated with venous invasion, tumor size and tumor node metastasis stage. Furthermore, the optimal cutoff of 0.78 for the level of TIPE2 mRNA has a sensitivity of 97.56% and a specificity of 88.16% for discriminating HCC from patients with CHB and liver cirrhosis.

CONCLUSIONS

TIPE2 mRNA was associated with various stages of chronic HBV infection, ranging from CHB to liver cirrhosis and HCC. Furthermore, TIPE2 mRNA with an optional cutoff value of 0.78 might serve as a promising biomarker to discriminate HBV-associated HCC from CHB and LC patients.

[Effect of oral appliance treatment on age-related changes of sleep respiratory function in patients with obstructive sleep apnea hypopnea syndrome]

Objective: The severity of obstructive sleep apnea hypopnea syndrome (OSAHS) has a tendency to increase with age. The purpose of this study was to explore whether oral appliance (OA) treatment can block this age-related change. Methods: This study was a retrospective study. Fifteen patients (12 males,3 females) of OSAHS treated with OA were selected as treatment group,with an average age of (47.44±10.00) years and initial body mass index (BMI) of (26.31±3.33) kg/m(2). The follow-up length was 54 [22, 100] months. Nineteen patients (13 males,6 females) with untreated OSAHS served as controls, with an average age of (45.00±9.26) years and initial BMI of (25.53±2.58) kg/m(2),and the follow-up length was 35 [26,63] months. There were no significant differences in terms of gender,age,initial BMI, apnea hypopnea index(AHI), and follow-up length between the two groups. Polysomnography(PSG) data for the two groups were compared to observe the sleep respiratory function changes as aging by Wilcoxon test. Results: There was no significant difference in BMI of the treatment group and the control group at the time of follow-up, with BMI of treatment group from (26.31±3.33) kg/m(2) to (25.67±3.65) kg/m(2),Z=-1.223,P=0.221; and BMI of control group from (25.53±2.58) kg/m(2) to (25.12±2.72) kg/m(2),Z=-1.193,P=0.233. There was no significant difference in the change of AHI within the treatment group, from 26.20 [11.50, 52.98]/h to 23.10 [16.00, 45.00]/h, Z=-0.284, P=0.776; AHI in the control group was higher than that at the first visit, and the AHI increased from 15.00 [10.72, 28.90]/h to 31.10 [13.00, 41.80]/h, Z=-3.481, P<0.001. The longest apnea duration was not statistically different in the treatment group, from 60.00 [56.40, 74.00] s to 63.00 [52.00, 77.00] s, Z=-0.345, P=0.730; the longest apnea duration in the control group increased from 42.00 [34.00, 56.70] s to 46.00 [37.00,62.00] s,Z=-2.274,P=0.023. There was no significant difference in the lowest blood oxygen saturation of the treatment group and the control group, with the treatment group from 72.47%±12.69% to 72.73%±17.59%, Z=-0.597, P=0.550; and the control group from 78.21%±9.30% to 76.42%±12.17%, Z=-0.153, P=0.879. Conclusion: Symptoms of sleep apnea in OSAHS patients tend to increase with age,and oral appliance treatment may have the effect of slowing down this age-related worsening effect.

[Relationship between overnight urinary sodium to potassium ratio and the risk of cardiovascular disease]

Objective: To explore the relationship between overnight urinary sodium to potassium ratio and the risk of cardiovascular disease (CVD). Methods: A subsample of 10 percent of the participants (35-59 years old) from the People's Republic of China-United States Collaborative Study of Cardiovascular and Cardiopulmonary Epidemiology (prospective survey) were used. Three consecutive overnight urine samples were collected in the autumn of 1983-1984 and the spring in 1985-1986, respectively. Urinary sodium and potassium were detected and calculated for 8 hours excretion. The occurrences of cardiovascular events were recorded in 2 years interval from 1987-1988 until December 31, 2005. Participants were divided into first ratio group, second ratio group, and third ratio group based on the tertiles of sodium to potassium ratio. Cox proportional hazard regression model was used to determine the relationship between sodium to potassium ratio and risk of CVD. In addition, participants were divided into 2 subgroups by the median of overnight urinary sodium and potassium, and then combined each other for 4 subgroups including low sodium-low potassium group, low sodium-high potassium group, high sodium-low potassium group, and high sodium-high potassium group, to explore the relationship between different sodium-potassium combinations and the risk of CVD. Results: A total of 954 participants were included in the final analysis, of whom 459 (48.1%) were males. There were 318 cases in the first, second and third ratio group, respectively. There were 347 cases in low sodium-low potassium group and high sodium-high potassium group, and 130 cases in low sodium-high potassium group and high sodium-low potassium group. After a median follow-up of 18.6 (18.3, 19.3) years, cardiovascular events occurred in 81 participants, including 64 stroke and 20 coronary heart disease events. Multivariate analysis showed that comparing with the first ratio group, the hazard ratios (HR) in the second and the third ratio groups were 2.04 (95%CI 1.06-3.95, P=0.034) and 2.07 (95%CI 1.07-4.03, P=0.032), respectively. The CVD risk in low sodium-low potassium group was 24% higher than the low sodium-high potassium group (reference), but this result did not reach statistical significant level (P=0.685). The risks in high sodium-high potassium group (HR=3.32, 95%CI 1.26-8.76,P=0.015) and high sodium-low potassium (HR=3.04, 95%CI 1.05-8.83, P=0.041) group were both significantly increased. Conclusions: Overnight urinary sodium to potassium ratio is positively correlated with the risk of cardiovascular events. High urinary sodium plays a more important role for the increased risk of cardiovascular events than low potassium.

A model to predict the onset of non-alcoholic fatty liver disease within 2 years in elderly adults

BACKGROUND AND AIM

Non-alcoholic fatty liver disease (NAFLD) is a common cause of chronic hepatitis, which leads to cirrhosis and hepatocellular carcinoma. However, it is difficult to identify subjects at high risk for NAFLD onset. This study aims to construct a model to predict the onset of NAFLD within 2 years in elderly adults.

METHODS

This study included and followed 3378 initial NAFLD-free subjects aged 60 years or over for 2 years, which were randomly divided into a training set and a validation set. NAFLD was diagnosed on ultrasound. Clinical and laboratory data were recorded at baseline. A model was constructed in the training set to predict the onset of NAFLD and validated in the validation set.

RESULTS

Body mass index, hemoglobin, fasting blood glucose, and triglycerides were identified as predictors for the onset of NAFLD. A risk score (R) was calculated by them. It classified the subjects into low-risk group (R ≤ -2.88), moderate-risk group (-2.88 < R ≤ -1.26), and high-risk group (R > -1.26). In the training set, 4.68% of the participants in the low-risk group, 11.59% of the participants in the moderate-risk group, and 31.02% of the participants in the high-risk group developed NAFLD. In the validation set, 5.84% of the participants in the low-risk group, 10.57% of the participants in the moderate-risk group, and 29.44% of the participants in the high-risk group developed NAFLD.

CONCLUSIONS

This study developed a model to predict the onset of NAFLD in elderly adults, which might provide indications for intervention to these subjects.

[Treatment outcome evaluation of different mandibular advancements using oral appliance to treat obstructive sleep apnea and hyponea syndrome: a systematic review]

OBJECTIVE

To evaluate the polysomnology results along with mandibular titrated advancement using oral appliance to treat obstructive sleep apnea and hyponea syndrome (OSAHS).

METHODS

Several electronic databases (PubMed, Embase, Cochrane Library, CNKI, VIP, and Wanfang) were systematically searched up to September 2015. There was no restriction of language or source of information. All randomized clinical trials (RCT) and before-after trials (BAT) comparing at least two different mandibular advancements were included. Two independent reviewers selected the studies, extracted data and evaluated risk of bias by quality assessment. Data were pooled using a fixed-effects model, and the summary effect measure was calculated by risk ratio (RR) and 95%CI. Meta-analysis was performed using RevMan 5.3 software.

RESULTS

Two RCTs and five BATs were included in the review. Among the five BATs, two of them were randomized, while the other three were not. Outcomes including apnea hypopnea index (AHI), oxygen desaturation index (ODI), success rate (reduction of AHI or ODI >50%), normalization rate (AHI or ODI<10/h) were assessed in this review. Based on the trial design and quality assessment, four studies were included for meta-analysis. No significant difference in the success rate was found between the group with 50% of the maximal mandibular advancement (MMA) and the group with 75% of MMA [I²=0%, RR=0.93, with 95%CI (0.80, 1.09)]. No significant difference in the normalization rate was found between the 50% of MMA and 75% of MMA groups [I²=45%, RR=0.85, with 95%CI (0.68, 1.06)]. Subgroup analysis displayed that the severity of OSAHS before treatment was a potential factor affecting the normalization rate.

CONCLUSION

Based on current available evidence, the success rate and normalization rate for treating OSAHS in the patients with 75% MMA were not found to be significantly higher than those with 50% MMA. Due to small simple size in this meta-analysis, the results of the present study should be interpreted with caution. Further prospective studies are needed to strengthen the evidence.

[Efficacy of oral appliance therapy of obstructive sleep apnea and hypopnea syndrome in different periods of treatment]

OBJECTIVE

To investigate the long-term efficacy of oral appliance treating of obstructive sleep apnea and hypopnea syndrome (OSAHS) in different periods of treatment.

METHODS

A total of 55 patients were included in the study. Patients were all diagnosed with OSAHS by overnight polysomnography and all received oral appliance (OA) as the therapy. The OA positioned the mandible at 60%-70% of the maximal mandible advancement position and created a 4-5 mm incisor separation. The patients were instructed to wear the appliance during sleep, 6-8 hours per day, for 5-7 days per week. They were divided into four groups by the period of treatment, including less than 1 year group; 1-2 years group; 2-6 years group and 6-9 years group. The polysomnographic study was used to investigate the efficacy of the four groups. The outcome measures included the score on the apnea-hypopnea index (AHI), the longest apnea time and the lowest oxygen saturation (LSaO₂) levels during an overnight sleep.

RESULTS

The AHI decreased significantly in all the four groups. The less than 1 year group decreased from 24.50 (14.65, 54.05) to 7.40 (2.12,10.00) events/h (P<0.001); The 1-2 years group decreased from 19.50 (12.15, 39.23) to 1.80 (0.70, 6.58) events/h (P=0.001); The 2-6 years group decreased from 25.00 (11.41, 42.60) to 4.50 (1.35, 7.90) events/h (P=0.001); The 6-9 years group decreased from 26.2 (16.95, 47.45) to 4.00 (1.90, 26.70) events/h (P=0.043). The longest apnea decreased significantly in less than 1 year group, 1-2 years group and 2-6 years group. The longest apnea decreased from 57.00 (37.70, 61.50) to 25.00 (15.90, 33.50) seconds (P<0.001) in the less than 1 year group, from 41.00 (25.50, 62.26) to 13.10 (0.00, 22.10) seconds (P=0.001) in the 1-2 year group and from 42.50 (30.35, 58.15) to 15.60 (0.00, 28.10) seconds (P=0.003) in the 2-6 year group. The LSaO₂ levels increased significantly in the less than 1 year group and 2-6 years group. The LSaO(2) levels rose significantly in the less than 1 year group, from 74.18%±7.96% to 84.06%±7.67% (P=0.001), and in the 2-6 years group, from 76.71%±10.98% to 84.06%±4.64% (P=0.006), The LSaO₂ levels did not increase significantly in the 1-2 years and 6-9 years groups. Kruskal-Wallis test showed that there were no statistically significant differences in the AHI, longest apnea time and LSaO(2) in 4 the groups.

CONCLUSION

The oral appliance is an effective therapy for patients with OSAHS in the long-term treatment. However, it's recommended to make appointments with patients as a follow-up supervision whether there is any efficacy decrease. And the oral appliance should be replaced if necessary.

T cell vaccination in systemic lupus erythematosus with autologous activated T cells

Systemic lupus erythematosus (SLE) is an autoreactive T cell mediated autoimmune disease. Immunization with inactivated autoreactive T cells may induce idiotype anti-idiotypic reaction to deplete specific subsets of autoreactive T cells involved in SLE. Six SLE patients unsuitable or refused to use immunosuppressants were treated with T cell vaccination. Their clinical manifestations and laboratory parameters including mixed lymphocyte reactions were evaluated. Autoreactive T cell clones were derived from peripheral blood mononuclear cells of the patients and 1 × 107 irradiated T cells were inoculated subcutaneously at 0, two, six and eight weeks, respectively. The enrolled patients were followed up for 32-40 months at an interval of three to six months. The clinical characteristics and laboratory abnormalities improved after inoculation without increasing the dose of corticosteroids and immunosuppressants in most patients. SLE disease activity index (SLEDAI) scores decreased. Proliferative responses against the T cell vaccine were observed in four of six patients. At the time of this report, the six patients remain in clinical remission. No significant side effect from the vaccination was noticed during the follow-up period. The results of this pilot study indicate that T cell vaccination is a safe and effective treatment in SLE.

A network approach predicts NFKBIA and BIRC3 as pathogenic genes in childhood asthma

This study aimed to predict pathogenic genes of childhood asthma based on molecular interaction networks and gene expression data. Known pathogenic genes identified from the human protein-protein interaction network were denoted as seed genes, and were included in network A. We extracted sub-network B (pathogenic network), which consisted of genes that interacted with at least two seed genes. We assigned a weight to select the pathogenic genes from this network according to its interactions and co-expressions with the seed genes. We also conducted ClusterONE analysis for the pathogenic network, and determined the statistical significance of the predicted clusters through a significance score (SS). Lastly, we investigated the biological pathways of the seed and candidate genes based on information obtained from the KEGG database. In network A, we identified 172 interactions and 125 genes that interacted with seed genes. In the pathogenic network, we found 51 genes and 102 interactions. The top 10 candidate genes with high weight scores were recorded. The SS of the predicted clusters demonstrated that 3 gene clusters were statistically relevant for childhood asthma. Pathway analysis showed that the seed genes and the top 10 candidate genes were significantly enriched in the same three biological processes. NFKBIA and BIRC3, which were involved in all three biological processes, may therefore be pathogenic genes. Using the network approach, we predicted that the pathogenic genes NFKBIA and BIRC3 are associated with childhood asthma. This information can provide guidelines for future experimental verification of childhood asthma.

Down-regulation of human leukocyte antigens class I on peripheral T lymphocytes and NK cells from subjects in region of high-incidence gastrointestinal tumor

BACKGROUND

Many types of human tumors can suppress the immune system to enhance their survival. Loss or down-regulation of human leukocyte antigens (HLA) class I on tumors is considered to be a major mechanism of tumor immune escape. Our previous studies found that HLA class I on peripheral-blood mononuclear cells was significantly lower in gastric cancer patients. The present study made an analysis of HLA class I expression on peripheral-blood T lymphocytes and NK cells from subjects of Lijiadian village, a village with high-incidence gastrointestinal tumor.

METHODS

A total of 181 villagers from Lijiadian village and 153 normal controls from the Department of Health Examination Center were enrolled in this study. Using a multi-tumor markers detection system, these villagers were divided into two groups: high-risk group (tumor markers positive group) and low-risk group (tumor markers negative group). The percentage of T lymphocytes and NK cells and levels of HLA class I on their surface were determined in these subjects by flow cytometry.

RESULTS

Percentages of T lymphocytes and NK cells in peripheral-blood mononuclear cells did not vary with age. The expression level of HLA class I on peripheral T lymphocytes and NK cells was not affected by age or gender, but was significantly down-regulated in Lijiadian villagers (P < 0.05), especially on the surface of NK cells (P < 0.01). Compared with the low-risk group, there was a significant reduction of HLA class I on peripheral T lymphocytes (P < 0.05) and NK cells (P < 0.05) in the high-risk group.

CONCLUSIONS

HLA class I on peripheral T lymphocytes and NK cells may be involved in tumorigenesis and development of gastrointestinal tumor, and understanding their changes in expression may provide new insights into the mechanism of tumor immunity.

Elevated levels of serum antibodies against Saccharomyces cerevisiae mannan in patients with systemic lupus erythematosus

This study was undertaken to investigate whether levels of anti- Saccharomyces cerevisiae mannan antibodies (ASCMAs), a serological marker for Crohn’s disease, seronegative spondyloarthritis and Behcet’s disease, also correlate with systemic lupus erythematosus (SLE) in humans. Serum samples from healthy volunteers ( n = 152) and patients with SLE ( n = 40) were compared for ASCMA-IgA, -IgG and -IgM levels using enzyme linked immunosorbent assays. ASCMA-IgG, but not IgM and IgA, prevalence was significantly raised in active SLE patients (57.5%) compared with healthy controls (8.5%). ASCMA-IgG levels in SLE patients during remission were relatively lower, indicating a possible correlation with disease activity. These results differ from a previous study, which did not detect a difference between ASCMA levels in SLE patients and healthy control. It remains to be evaluated whether elevated ASCMA-levels are common to all rheumatic disorders.

Pulse wave velocity as a marker of arteriosclerosis and its comorbidities in Chinese patients

To obtain reliable data on the epidemiology of arteriosclerosis and the comorbidities in patients with hypertension (HP), coronary heart disease (CHD), type 2 diabetes mellitus (T2DM) and stroke, we evaluated the clinical significance of pulse wave velocity (PWV) as an indicator of arteriosclerosis and its comorbidities in Chinese patients. A total of 910 subjects, including 748 Chinese patients with one or more cardiovascular risk factors (80.2% male, mean age 73.69+/-5.03 years) and 162 healthy volunteers (78.4% male, mean age 73.60+/-5.32 years) were recruited into the study. PWV was measured in 910 subjects, and large artery arteriosclerosis was defined as PWV >or=12 m/s. Multivariable logistic regression analyses were performed to identify risk factors associated with arteriosclerosis. The prevalence of large artery arteriosclerosis in the patients overall was 67.4%, and the prevalence was higher in patients with than in those without HP (63.3% vs. 34.0%; odds ratio [OR]: 3.451), T2DM (24.8% vs. 11.1%; OR: 2.854), CHD (56.1% vs. 45.1%; OR: 1.246) and stroke (26.6% vs. 19.2%; OR: 1.236), but the OR values of CHD and stroke did not differ significantly (p>0.05). After multiple logistic regression analysis, female sex, older age, HP and T2DM were risk factors for large artery arteriosclerosis. In conclusion, PWV can be used as a routine measurement to scan arteriosclerosis in patients with HP or T2DM.

[Clinical study of the distensibility of large arteries in elderly patients with essential hypertension]

OBJECTIVE

To explore the change in the distensibility of large arteries and its influencing factors in elderly patients with essential hypertension.

METHODS

Automatic measuring system for pulse wave velocity (PWV) was applied to examine carotid-femoral PWV as an index reflecting distensibility of large arteries. 118 hypertensive patients aged 64 - 83 (mean age 67.12 +/- 10.26) years were included in the study. Of them, 87 were males and 31 were females.

RESULTS

PWV of 118 hypertensive patients increased with increasing age (P < 0.001). Multivariate regressive analysis demonstrated that age and systolic blood pressure had the close relationship with PWV (P < 0.001).

CONCLUSION

Hypertension of the elderly could cause reduction of distensibility of large arteries. Age and systolic blood pressure had the close relationship with distensibility of large arteries in elderly patients with essential hypertension.

Selective fluorescence of zymogen granules of pancreatic acinar cells stained with hematoxylin and eosin

Following staining with hematoxylin and eosin Y, paraffin sections of mouse pancreas were examined by transmitted light, epifluorescence and confocal laser scanning microscopy. Light microscopy revealed that the nuclei of pancreatic acinar cells were located basally, while the apices of the cells appeared eosinophilic, although the secretory granules were difficult to visualize. Under violet-blue light excitation, the zymogen granules at the apices of the acinar cells showed strong yellowish fluorescence; the other part of the cytoplasm was only faintly fluorescent and the nuclei and the supporting tissues were nonfluorescent. Confocal laser scanning microscopy resulted in clear pictures of the zymogen granules and their distribution within the cell. The fluorescent emission of zymogen granules was certainly the result of eosin Y staining, because hematoxylin is not a fluorochrome and the zymogen granules are not autofluorescent. Staining with eosin Y alone, however, did not result in clear fluorescent images of zymogen granules or any other cellular structures. Our observation shows that the fluorescence emission of eosin Y allows easy and precise recognition of zymogen granules of pancreatic cells.

Reperfusion-induced Ins(1,4,5)P(3) generation and arrhythmogenesis require activation of the Na(+)/Ca(2+) exchanger

Reperfusion of globally ischemic rat hearts causes rapid generation of inositol(1,4,5) trisphosphate [Ins(1,4,5)P(3)] and the development of arrhythmias, following stimulation of alpha(1)-adrenergic receptors by norepinephrine released from the cardiac sympathetic nerves. The heightened inositol phosphate response in reperfusion depends on the activation of the Na(+)/H(+) exchanger, which might reflect a central role for increased Ca(2+)following reverse mode activation of the Na(+)/Ca(2+) exchanger (NCX). Isolated, perfused rat hearts were subjected to 20 min ischemia followed by 2 min reperfusion and the content of Ins(1,4,5)P(3) measured by mass analysis or by anion-exchange high performance liquid chromatography (HPLC) following [(3)H]inositol labeling. Reperfusion caused generation of Ins(1,4,5)P(3) (1266+/-401 to 3387+/-256 cpm/g tissue, mean+/-s.e.m., n=6, P<0.01) and the development of arrhythmias. Inhibition of NCX either by reperfusion at low Ca(2+) (1133+/-173 cpm/g tissue, mean+/-s.e.m., n=6, P<0.01 relative to reperfusion control) or by adding 10 microm KB-R7943, an inhibitor of reverse mode Na(+)/Ca(2+) exchange, prevented the Ins(1,4,5)P(3) response (1151+/-243 cpm/g tissue, mean+/-s.e.m., n=6, P<0.01 relative to reperfusion control) and the development of ventricular fibrillation. Lower concentrations of KB-R7943 were less effective. Reverse mode activation of NCX is therefore required for the enhanced Ins(1,4,5)P(3) response in early reperfusion, and inhibitors of this transporter may be useful in the prevention of arrhythmias under such conditions.

Cardiac output in mice overexpressing beta2-adrenoceptors or with myocardial infarct

1. The aims of the present study were to characterize cardiac output (CO) in transgenic mice that overexpress the beta2-adrenoceptor and to evaluate ultrasonic flowmetery for continuous CO measurement in the mouse in vivo. 2. Under conditions of anaesthesia, open chest and positive ventilation, CO was determined with a transonic flowmeter at baseline and during dobutamine administration and intravenous volume loading in wild-type mice (n = 17) and beta2-adrenoceptor transgenic (n = 9) and wild-type mice with chronic myocardial infarct (n = 16). 3. Compared with wild-type mice, beta2-adrenoceptor transgenic mice with markedly enhanced ventricular contractility had a significantly higher CO, heart rate (HR) and maximal acceleration of aortic flow. Both dobutamine and volume loading increased CO in the two groups and higher levels of CO were measured in transgenic mice during the interventions. At baseline or during interventions, stroke volume was similar between beta2-adrenoceptor transgenic and wild-type mice. Infarcted mice with impaired cardiac function had a significantly lower CO under basal and stress conditions. 4. Thus, beta2-adrenoceptor transgenic mice revealed higher CO that was largely attributable to a significantly higher HR but not to an increase in stroke volume. Transonic flowmetery can detect differences in CO among mice in various functional states and is suitable for evaluation of cardiac functional reserve in mice in vivo by continuous monitoring of CO responses to different interventions.

Traditional and new antipsychotic drugs differentially alter neurotransmission markers in basal ganglia-thalamocortical neural pathways

The effects of three chronically administered antipsychotic drugs on selected neurochemical markers of dopaminergic and GABAergic transmission were compared within the cerebral regions making up the basal ganglia-thalamocortical parallel processing neuronal pathways. All three drugs reduce psychosis in humans, whereas only haloperidol, but not olanzapine or sertindole, induce purposeless oral chewing movements (CMs) in rats or cause high rates of parkinsonism or tardive dyskinesia in humans. Male Sprague Dawley rats were treated with haloperidol, sertindole, or olanzapine delivered in drinking water for 6 months at doses which produce drug plasma levels in rat in the human therapeutic range. Results show the expected dopamine D2 receptor upregulation in striatum predominantly with haloperidol, although mild D2 upregulation was apparent in striatum after olanzapine. GAD67 mRNA was increased in striatum and decreased in globus pallidus by haloperidol and sertindole, but not by olanzapine. In the substantia nigra pars reticulata (SNR), both olanzapine and sertindole failed to induce GABA(A) receptor upregulation or D1 receptor downregulation, but haloperidol did both, confirming a previous report. In thalamus, all three drugs increased GAD expression in the reticular nucleus, whereas only haloperidol decreased GABA(A) binding in the mediodorsal nucleus, actions consistent with a reduction in nigrothalamic, GABA-mediated neural transmission. These results are consistent with the idea that the two new antipsychotics tested have mild and regionally restricted actions within the basal ganglia nuclei and a common action on increasing GAD expression in the reticular nucleus of the thalamus (RtN). Haloperidol, in contrast, has a broad and potent action in basal ganglia, causing changes in SNR and in the mediodorsal nucleus, while also altering GAD mRNA in RtN, potentially reflective of its dyskinetic and antipsychotic actions.

Scopolamine fails to diminish chronic haloperidol-induced purposeless chewing in rats

Chronic haloperidol treatment for 4-12 months gradually induces spontaneous, irregular, purposeless oral chewing movements (CMs), apparently involuntary, in some but not all treated rats. Based on phenomenologic and pharmacologic similarities, this laboratory preparation has been used as an animal model of tardive dyskinesia (TD), which is the human hyperkinetic motor syndrome associated with chronic antipsychotic administration. This putative animal model has received the most severe challenge to its validity by claims that its oral movements can be suppressed by anticholinergic treatments, since resistance to anticholinergic suppression is an accepted pharmacologic feature of TD. In this experiment, we challenged a group of haloperidol-treated rats with CMs using three doses of scopolamine (0.1, 0.3, 1.0 mg/kg) and placebo and rated the change in dyskinetic movements. Each scopolamine dose reduced CMs by a similar magnitude, without any dose effect; the saline dose also reduced CMs to an equivalent degree. Therefore, we concluded that some component of the experiment, not the scopolamine, reduced the CMs. The handling component of the procedure was identified as a likely confound, and we tested this further. Rats with CMs were handled at several levels of "severity"; and the dyskinesias were rated at 1 and 3 h later. CMs were reduced by the experimental handling, in relation to the strength of the handling. Minimal handling produced modest CM reductions with quick recovery; whereas, the "strongest" handling plus the placebo injection produced the greatest CM reduction, evident over 3 h, resembling the CM reductions seen in the scopolamine and placebo experiment. Overall, these results suggest that anticholinergic drugs do not suppress chronic haloperidol-induced rat CMs. However, the movements are sensitive to stressful handling situations, and diminish with stress. In both of these characteristics, rat CMs resemble human TD, further supporting a role for this model in studies of human TD.

Age-dependent cardiomyopathy and heart failure phenotype in mice overexpressing beta(2)-adrenergic receptors in the heart

OBJECTIVE

To explore long-term cardiac phenotype in transgenic (TG) mice with 300-fold overexpression of beta(2)-adrenergic receptors (AR).

METHODS

Echocardiography was performed serially on a cohort of wild-type and TG mice (n=26 each) between 4 and 15 months of age. Survival was monitored and autopsy and histological examinations were performed.

RESULTS

Heart rate was higher in TG than in wild-type mice throughout the study period. The left ventricular dimensions and fractional shortening were similar between TG and wild-type groups during 4-6 months. Starting at 9 months, however, TG mice showed progressive reduction in fractional shortening and systolic wall thickening, and increase in left ventricular dimensions and left ventricular mass, indicating onset of heart failure, left ventricular hypertrophy and remodeling. Abnormal waveforms in the electrocardiogram and episodes of ventricular ectopic beats were also observed in TG mice. Death of TG mice started at 8.5 months, and the cumulative mortality was 81% by 15 months (P<0.0001 vs. 4% in wild-type mice). The majority of deaths were due to severe heart failure, indicated by cardiac dilatation, lung congestion, pleural effusion and atrial thrombus. Left ventricular sections showed widespread interstitial fibrosis, loss of myocytes and myocyte hypertrophy in TG mice.

CONCLUSIONS

A high level of beta(2)AR overexpression results in cardiomyopathy and heart failure. The onset was slower and the expression levels of receptors required are much higher than previously described for the beta(1)AR overexpression.

Preserved ventricular contractility in infarcted mouse heart overexpressing beta(2)-adrenergic receptors

Effects of cardiac specific overexpression of beta(2)-adrenergic receptors (beta(2)-AR) on the development of heart failure (HF) were studied in wild-type (WT) and transgenic (TG) mice following myocardial infarction (MI) by coronary artery occlusion. Animals were studied by echocardiography at weeks 7 to 8 and by catheterization at week 9 after surgery. Post-infarct mortality, due to HF or cardiac rupture, was not different among WT mice, and there was no difference in infarct size (IS). Compared with the sham-operated group (all P < 0.01), WT mice with moderate (<36%) and large (>36%) IS developed lung congestion, cardiac hypertrophy, left ventricular (LV) dilatation, elevated LV end-diastolic pressure (LVEDP), and suppressed maximal rate of increase of LV pressure (LV dP/dt(max)) and fractional shortening (FS). Whereas changes in organ weights and echo parameters were similar to those in infarcted WT groups, TG mice had significantly higher levels of LV contractility in both moderate (dP/dt(max) 4,862 +/- 133 vs. 3,694 +/- 191 mmHg/s) and large IS groups (dP/dt(max) 4,556 +/- 252 vs. 3,145 +/- 312 mmHg/s, both P < 0.01). Incidence of pleural effusion (36% vs. 85%, P < 0.05) and LVEDP levels (6 +/- 0.3 vs. 9 +/- 0.8 mmHg, P < 0.05) were also lower in TG than in WT mice with large IS. Thus beta(2)-AR overexpression preserved LV contractility following MI without adverse consequence.

Expression of active alpha(1B)-adrenergic receptors in the heart does not alleviate ischemic reperfusion injury

Ischemic preconditioning reduces infarct size and improves cardiac function in various species, including mice. The mechanism for ischemic preconditioning protection is not entirely clear and activation of alpha(1B)-adrenergic receptors (AR) is believed to be involved. Transgenic mice expressing constitutively active mutant alpha(1B)-AR in the heart have enhanced alpha(1B)-AR activity and therefore can be used to test the role of alpha(1B)-AR in ischemic preconditioning. Wild-type and transgenic mice were subjected to 30- or 40-min periods of left coronary artery occlusion followed by 60-min reperfusion, or ischemic preconditioning prior to sustained ischemia-reperfusion. Risk and infarct zones were determined by staining with Evans blue and triphenyltetrazolium, respectively, and quantitated digitally. Infarct zone and infarct size were not different between wild-type and transgenic mice, nor was the extent of reduction in infarct size by preconditioning ischemia (wild-type mice: 45+/-3 to 18+/-3%, transgenic mice: 46+/-3 to 19+/-2% of the left ventricle, both P<0.01). Ventricular function was similar between wild-type and transgenic mice with or without ischemia-reperfusion injury. In conclusion, enhanced alpha(1B)-AR activity by cardiac-specific expression of constitutively active mutant alpha(1B)-AR in mice does not mimic ischemic preconditioning to protect against ischemia-reperfusion injury.

Ionotropic glutamate receptors and expression of N-methyl-D-aspartate receptor subunits in subregions of human hippocampus: effects of schizophrenia

OBJECTIVE

Multiple quantifiable biologic abnormalities have been localized to the hippocampus in schizophrenia. Alterations in glutamate-mediated transmission at N-methyl-D-aspartic acid (NMDA)-sensitive receptors in hippocampus have been implicated in the pathophysiology of the illness. The authors tested the hypothesis that glutamatergic transmission within and efferent from hippocampus is altered in schizophrenia.

METHOD

The authors analyzed postmortem hippocampal tissue from individuals with schizophrenia and from healthy individuals. The tissue samples had been collected by two brain tissue banks, one in Maryland and the other in Melbourne, Australia. lonotropic receptor binding for the NMDA, kainate, and (3)H-amino-3-hydroxy-5-methylisoxazol-4-propionate (AMPA) receptors was quantified by using usual radioligand techniques. In situ hybridization autoradiography was used to quantify mRNA for the NMDA receptor subunits NR1, NR2A, and NR2B.

RESULTS

Ligand binding to the ionotropic glutamate receptors (NMDA, kainate, and AMPA) did not differ significantly overall or in any subregion between the schizophrenia tissue and the healthy comparison tissue. The only exception was AMPA receptor binding in hippocampal subregion CA2, which was slightly but significantly less in schizophrenia. However, the level of mRNA for the NMDA receptor subunits NR1 and NR2B was significantly different between groups; in several hippocampal subregions, the level of NR1 mRNA was lower and the level of NR2B mRNA higher in schizophrenia.

CONCLUSIONS

Because the NR1 subunit of the NMDA receptor is critical to full receptor activity, a reduction of NR1 in hippocampus in schizophrenia suggests a functional impairment in glutamatergic transmission at the NMDA receptor, resulting in reduced glutamatergic transmission within and possibly efferent from the hippocampus in schizophrenia. This defect could underlie a hypoglutamatergic state in regions of limbic cortex, consistent with published results from other lines of research in schizophrenia.

Characterisation of Candida albicans infections of haematogenous and mucosal origin in mice lacking the interferon gamma receptor protein

Mice harbouring a null deletion mutation in the IFNgamma receptor gene were used to study the role of IFNgamma responsiveness during experimental systemic candidiasis of mucosal or haematogenous origin. After intravenous (i.v.) or intranasal (i.n.) challenge with Candida albicans the progression of infection and concomitant cellular and antibody anti-C. albicans immune responses were analysed. During the week following i.v. challenge, the rate of C. albicans multiplication in kidneys, liver and spleen was faster in IFNgammaR (-/-) than IFNgammaR (+/+) mice. As a result, IFNgammaR (-/-) mice perished earlier than IFNgammaR (+/+) mice when challenged with equal numbers of live yeast cells. However, the overall susceptibility of the two mouse strains, in terms of survival against different C. albicans challenge doses over a 60-day period, was similar. No differences were found in the cellular anti-C. albicans response generated by i.v. challenge in both mouse strains. In contrast the kinetics and strength of the serum anti-C. albicans antibody responses were markedly different. Significantly stronger, predominantly IgG2a antibody responses accompanied the eventual control of C. albicans infection in IFNgammaR (-/-) mice. Following intranasal challenge, there was no difference in the rate of C. albicans clearance from the lungs of IFNgammaR (-/-) and IFNgammaR (+/+) mice. However, 48 h after challenge, large, conspicuous abscesses appeared in the lungs, liver, kidneys and spleen of IFNgammaR (-/-) mice. These abscesses were characterised by the presence of C. albicans and abundant neutrophilic infiltrates, but very few macrophages. No such abscesses developed in i.n. challenged IFNgammaR (+/+) mice. In both mouse strains, i.n. challenge induced strong systemic anti-C. albicans cellular responses, but relatively low titre systemic antibody responses. Mucosal anti-C. albicans antibody responses were detected in IFNgammaR (+/+), but not IFNgammaR (-/-) mice. Splenic adherent macrophages obtained from IFNgammaR (-/-) mice exhibited a significantly lower candidacidal activity than those of IFNgammaR (+/+) mice, and as expected, were not responsive to IFNgamma. In summary, these data suggest that IFNgamma has a role in limiting C. albicans multiplication during the early stages of infection, as well as in preventing the development of C. albicans-associated abscesses. Activation of macrophages by IFNgamma might be pivotal in mediating this role.

Serial echocardiographic assessment of left ventricular dimensions and function after myocardial infarction in mice

OBJECTIVE

To test the usage of serial echocardiography in mice with induced myocardial infarct (MI) and to characterize the mouse model of MI.

METHODS

C57 mice underwent open-chest surgery to induce left coronary artery occlusion or sham-operation (SH). Echocardiography was performed before and at 1, 2.5, 6 and 9 weeks after surgery. Left ventricular end diastolic and end systolic dimensions (LVEDd, LVESd) and fractional shortening (FS) were measured. Haemodynamics was determined at week 9 by LV catheterization and hearts were examined morphologically.

RESULTS

Post-infarct mortality was 46% (10/22), of which, 70% died of acute heart failure or LV rupture within the first week. LV dimensions and FS remained stable in SH group (n = 10) during the study period. In surviving MI mice (n = 12), there was modest LV dilatation and fall in FS at week 1. Compared with week 0 values, there were progressive increase in LVEDd (+50(-)+66%) and LVESd (+124(-)+171%), and decline in FS (-53(-)-73%) during the 2.5-9 week period. Infarcted mice also had lower LV systolic pressure (LVSP), dP/dtmax and dP/dtmin (all P < 0.01 vs. SH group). Infarct size, LVSP and dP/dt significantly correlated with FS and LV dimensions (r = 0.61-0.80, all P < 0.01).

CONCLUSIONS

LV remodeling and dysfunction in mice with MI are time-dependent processes and early remodeling seems associated with high risk of rupture and acute pump failure. Our findings provide a baseline description of this murine model and confirm echocardiography as a reliable means to serially assess changes of cardiac structure and function after MI.

Magnetic resonance imaging of the upper airway in obstructive sleep apnea before and after oral appliance therapy

OBJECTIVE

To determine the mechanism by which an oral appliance may be used to treat obstructive sleep apnea syndrome (OSAS).

METHODS

Eleven OSAS patients (8 males and 3 females) were involved in the study. Mean age was 52.2 +/- 10.6 years; height was 166.6 +/- 7.2 cm, and weight was 75.6 +/- 9.3 kg; body mass index (BMI) was 27.2 +/- 2.9 kg/m2. Each patient underwent magnetic resonance imaging (MRI) and polysomnography before and after oral appliance therapy. Pharyngeal changes were measured and compared with the variation in sleep parameters. Also, Pearson's correlation and multiple linear regression were performed to investigate the relationship of sleep parameters and MRI items.

RESULTS

Through oral appliance therapy, the sleep disorder decreased. Apnea/hypopnea index (AHI) decreased from 44.6 +/- 21.5 to 9.6 +/- 6.3 per hour of sleep. Lowest oxygen desaturation rose from 71.4 +/- 15.0% to 82.0 +/- 7.7%. Meanwhile, the upper airway increased at most levels, and especially at oropharynx. As measured by the correlation and regression analysis, the AHI changes had a negative association with tongue volume (R = -0.5730) and a positive association with the area alternation of high oropharynx (R = 0.5823); the change of the lowest oxygen desaturation (SaO2%) was positively associated with whole airway volume (R = 0.6554).

CONCLUSION

The oral appliance works by enlarging the upper airway morphology and keeping the airway open, mainly at the back of soft palate. The effect of the oral appliance is associated with the degree of enlargement of the high oropharynx. Those who have a small tongue and a large pharynx may expect to have good results with the use of the oral appliance.

Chronic olanzapine or sertindole treatment results in reduced oral chewing movements in rats compared to haloperidol

Chronic haloperidol treatment typically produces late-onset, purposeless oral chewing movements in laboratory rats with a prevalence of 40 to 60%. Chronic clozapine does not produce these movements. Based on the phenomenologic and pharmacologic similarities between these rat chewing movements and human tardive dyskinesia (TD), the animal movements are often used as a model of tardive dyskinesia (TD). Here we report results of the association of oral chewing movements in rats with chronic administration of two new antipsychotic drugs, olanzapine and sertindole. Because each of these antipsychotic drugs has a very low incidence of acute Parkinsonism in human studies, they are candidates for showing a low tardive dyskinesia risk. Neither new drug produced a significant incidence of haloperidol-like chewing in rats, nor did movement ratings after their chronic administration differ from placebo; whereas, haloperidol produced a 60% prevalence of purposeless chewing and a prevalence significantly increased from placebo. This low rate of oral dyskinesias in rats is consistent with several of the preclinical characteristics of the drugs and correlates with their low acute motor side effects in clinical trials. We propose, although have not yet tested in humans, that these animal results will predict low TD liability of these drugs.

Mixture in the distribution of haloperidol-induced oral dyskinesias in the rat supports an animal model of tardive dyskinesia

Spontaneous adventitious oral movements which are produced in rats by very chronic (6-month) neuroleptic treatment have some phenomenologic and pharmacologic characteristics in common with tardive dyskinesia in humans. However, since not all of the features match, this putative model has been questioned and further support is warranted. Data from several laboratories support dichotomizing these neuroleptic-induced rat oral movements into "low" or "not TD-like" movements and "high" or "TD-like" movements, similar to the division of neuroleptic-induced involuntary movements in humans. Here, we have used mixture analysis to test this proposal statistically in 185 haloperidol-treated and 127 water-treated animals. Rats from several different studies were grouped together to form these two cohorts. The haloperidol dose, route of administration, rating technique, and balanced experimental groups were held constant across all experiments. Results show that two distinct groups of rat movements are induced by very chronic haloperidol treatment (1.5 mg/kg per day). The "low" vacuous chewing movement (VCM) group of rats had an average of 3.6 VCMs/5 min, and the "high" VCM group had an average of 16.1 VCMs/5 min; the control group, with a median VCM rate of 2.0 VCMs/5 min, demonstrated a single distribution. These data suggest that rats, like humans, dichotomize into two groups either expressing or not expressing "high" VCM dyskinesias with very chronic haloperidol treatment.

Phencyclidine (PCP) and dizocilpine (MK801) exert time-dependent effects on the expression of immediate early genes in rat brain

The mRNA expression pattern for four different immediate early genes was examined dynamically in rat brain after administration of phencyclidine (PCP; 0.86 or 8.6 mg/kg) or MK801 (0.1 or 1.0 mg/kg). Following each treatment, the expression of cfos, cjun, junB, and zif268 mRNA changed distinctively and dynamically between 1 and 48 hours. cfos mRNA was induced in cortical areas at early times after either dose of PCP or of MK801; the change was especially prominent in cingulate and auditory cortices. zif268 mRNA showed an early (1 hour) activation and a delayed (24-48 hour) suppression after PCP and MK801 in neocortical areas. PCP also caused cjun and junB mRNA induction in cortical areas at early times, with a distribution and time course similar to its effects on cfos mRNA. No alterations in cfos, cjun, or junB mRNA were found in neocortical or hippocampal areas at any delayed time (>6 hours) after PCP treatment, whereas suppression of zif268 expression was prominent even at 48 hours post-treatment. CPP, a competitive NMDA antagonist, showed a similar pattern of effects on cfos and zif268 mRNA expression. These functional consequences of a PCP- or MK801-induced reduction in NMDA-sensitive glutamate transmission may be relevant to an understanding of animal NMDA pharmacology and/or to clinical psychotomimetic side effects of antiglutamatergic treatments.

TCR usage by homocysteine-specific human CTL

We have recently demonstrated that homocysteine can modify HLA class I Ags and induce homocysteine-specific CTL (Hom-CTL) responses in humans. Here, we have investigated TCR usage by Hom-CTL from five patients with ankylosing spondylitis or reactive arthritis. TCR of HLA-A68-restricted Hom-CTL from two unrelated donors share the same TCR Valpha, Vbeta, and Jbeta gene segments (AV4, BV23, and BJ2S1, respectively) with similar third complementarity determining regions (CDR3) of the beta-chains. Interestingly, the Va and Vbeta gene segments employed by an HLA-B27-restricted Hom-CTL clone are also closely related to AV4 and BV23, indicating strong selection pressure for AV4, BV23, and related gene products in the homocysteine-specific TCR. An arginine or lysine residue frequently appeared at position alpha93 in the CDR3 of the TCR alpha-chains from Hom-CTL restricted by HLA-A68 or -B8. This may suggest a potential salt bridge between the carboxyl group of homocysteine and specific TCR. TCR usage by HLA-B27-restricted Hom-CTL from unrelated individuals appears to be less conserved, although two T cell clones from one individual rearranged the same V gene segments with identical lengths of CDR3. Implications of these data for the molecular mechanisms for homocysteine modification of HLA Ags are also discussed.

The effect of chronic haloperidol treatment on dendritic spines in the rat striatum

Previous studies have shown that schizophrenics, in comparison to controls, have reduced cortical spine density and smaller striatal spines. The current study in the rat was conducted to determine whether such differences could result from chronic neuroleptic treatment and whether they are correlated with neuroleptic-induced oral dyskinesias. Rats administered 1.5 mg/kg/day of haloperidol (HA) (n = 28) or water (n = 10) were tested for vacuous chewing movements (VCMs). After 6 months, rats were divided into low and high VCM groups; all but seven high VCM rats were sacrificed. These rats (withdrawn group) were withdrawn from HA for 4 weeks. Random electron micrographs of the striatum were analyzed for spine changes. Spine size was not significantly affected by HA (0.193 vs 0.174 microm2, HA and control, respectively) nor correlated with oral dyskinesias (0.191 vs 0.196 microm2, low and high VCM groups, respectively). These results suggest that smaller spines in schizophrenic striatum may be correlated with the disease rather than caused by neuroleptic treatment. Spine density decreased in the HA-treated group (32.7 +/- 9.5) in comparison to controls (53.7 +/- 7.3, P < 0.001) and remained low in the withdrawn group (35.0 +/- 4.2, P < 0.01). Spine density also decreased in both the low (37.3 +/- 9.9, P < 0.01) and the high (28.0 +/- 7.0, P < 0.000) VCM groups in comparison to controls. However, there was no significant difference between high and low VCM groups, suggesting that decreased spine density is independent of oral dyskinesias. These results suggest that the decreased spine density observed in schizophrenic cortex may be a result of neuroleptic treatment.

Immunization of mice with DNA encoding fragment C of tetanus toxin

Immunization of mice with Fragment C protein, the non-toxic C-terminal domain of tetanus toxin, will protect mice against lethal challenge with tetanus toxin. A plasmid, pcDNA3/tetC, which encodes a synthetic tetC gene expressed under the control of the human cytomegalovirus major intermediate early promoter/enhancer region, was constructed. Fragment C expression was observed in Chinese hamster ovary cells following transfection with pcDNA3/tetC. The immune response induced by intramuscular immunization with pure pcDNA3/tetC DNA was evaluated in a murine model. Anti-Fragment C serum immunoglobulin and proliferative responses in splenocytes were observed following two immunizations with pcDNA3/tetC. The major IgG subclass that recognized Fragment C was IgG2a and the stimulated splenocytes secreted high levels of interferon-gamma. Sufficient anti-Fragment C serum immunoglobulins were induced by DNA-mediated immunization to protect mice against lethal challenge with tetanus toxin.

The dose-response characteristics of rat oral dyskinesias with chronic haloperidol or clozapine administration

Whether the pathophysiology and treatment of neuroleptic-induced oral dyskinesias in rats parallel that for tardive dyskinesia in humans remains a question. To address the issue further, Sprague Dawley rats were treated for 6 months with multiple oral doses of haloperidol (1.5 and 3.0 mg/ kg/day) or clozapine (10, 20, and 30 mg/kg/day) and compared with water treated animals. The rate of oral dyskinesias was monitored at study start and monthly by trained raters who were blind to treatment group. All haloperidol-treated rats developed oral dyskinesias at a significantly higher rate than rats treated with water (p = 0.0007) or those treated with clozapine (p = 0.0017). Each dose of haloperidol produced significantly higher rates of oral dyskinesias than did any dose of clozapine and did so in an apparent dose-sensitive manner. Clozapine lacked a dose-sensitive relationship with the oral dyskinesias, and failed to show a significant difference in rate from control rats at any dose. Plasma levels of haloperidol with these doses were in the human therapeutic range; with clozapine only the highest dose produced plasma levels in the human therapeutic range. These data show little association between rat oral dyskinesias and clozapine treatment, whereas a strong association is present with haloperidol. The data are, thereby, consistent with the clinical association of tardive dyskinesia with typical neuroleptics like haloperidol but not with the atypical neuroleptic clozapine.

Immune response in mice following immunization with DNA encoding fragment C of tetanus toxin

Tetanus toxin is a potent neurotoxin synthesized by Clostridium tetani. Immunization with fragment C protein, the nontoxic C-terminal domain of tetanus toxin, will protect mice against lethal challenge with tetanus toxin. A synthetic gene encoding fragment C (tetC) had previously been shown to express high levels of fragment C in Saccharomyces cerevisiae. A plasmid, pcDNA3/tetC, which encodes the synthetic tetC gene expressed under the control of the human cytomegalovirus major intermediate-early promoter/enhancer region, was constructed. Expression of fragment C was observed in eukaryotic cells growing in vitro following transfection with pcDNA3/tetC. The immune response induced by intramuscular immunization with pure pcDNA3/tetC DNA was evaluated in a murine model. Anti-fragment C serum immunoglobulin and proliferative responses in splenocytes were observed in BALB/c mice following two immunizations with pcDNA3/tetC. The major immunoglobulin G subclass that recognized fragment C was immunoglobulin G2a, and the stimulated splenocytes secreted high levels of gamma interferon. Immunity to tetanus is dependent on the presence of neutralizing serum antibodies against tetanus toxin. Sufficient anti-fragment C serum immunoglobulins were induced by DNA-mediated immunization to protect mice against lethal challenge with tetanus toxin.

Phencyclidine produces changes in NMDA and kainate receptor binding in rat hippocampus over a 48-hour time course

Phencyclidine (PCP) is a psychotomimetic drug associated with acute and delayed mental effects in normal humans and psychosis exacerbation in already psychotic schizophrenic individuals. We have previously described a dose-sensitive, delayed action of PCP on regional cerebral metabolism in the rat which occurs over 48 hours and a late (24 hour) change in N-methyl-d-aspartate (NMDA) and kainate binding in hippocampal areas. Now, we report the complex time course of PCP action on NMDA-sensitive glutamate receptor binding in rat in distinct subregions of the hippocampus extending over 48 hours. Selectively, in the hippocampal CA1 region, a single dose of PCP (8.6 mg/kg) produced an increase in receptor binding at 12 hours (+24%), sustained to 24 hours (+29%) compared with the 3 hour post-PCP value (-15%) and then a return to control levels of receptor binding at 48 hours. Other regions of hippocampus showed distinctive time-dependent changes in NMDA-sensitive glutamate receptor binding as well. In addition, PCP produced a change in kainate receptor binding in the dentate gyrus across the 48-hour time period. In other representative brain regions, PCP did not alter NMDA or kainate binding over the same time course. This extended neurochemical effect of PCP on glutamate receptors in rat hippocampus parallels, in time, certain delayed psychological actions of PCP in humans and thus may be relevant to psychosis, especially to PCP-induced psychosis.

Homocysteine modification of HLA antigens and its immunological consequences

Homocysteine-treated cells can be specifically lysed by cytotoxic T lymphocytes (CTL) identifiable in patients with ankylosing spondylitis and reactive arthritis. Sensitization of target cells involves disulfide bonding and the interaction between homocysteine and HLA antigens occurs in a pre-Golgi compartment in the cells. Salmonella-infected B cells are also lysed by homocysteine-specific CTL, suggesting that intracellular invading microorganisms may provide homocysteine which would gain access to the newly synthesized intracellular HLA molecules and modify them inside the cells. Two different mechanisms for homocysteine modification of HLA antigens are proposed: homocysteine could bind directly to the unpaired cysteine residues in HLA antigens, or it could bind indirectly to HLA antigens through cysteine-containing peptides bound to them. Thus, HLA antigens containing unpaired cysteine residues (e.g. HLA B27) could be modified by homocysteine directly or indirectly, while HLA antigens without unpaired cysteine residues (e.g. HLA A68) could only be modified indirectly. The results are discussed in relation to the potential involvement of homocysteine-specific CTL in ankylosing spondylitis and reactive arthritis, both of which are related to bacterial infections, associated with HLA B27, and considered to be autoimmune diseases.

Camptothecin post-treatments inhibit the biochemical events linked to the tumor-promoting component of carcinogenesis in mouse epidermis in vivo

20(S)-Camptothecin (CPT), a topoisomerase I inhibitor specifically toxic toward S-phase cells, was tested topically for its ability to inhibit the biochemical markers of skin tumor promotion. CPT has no or very little inhibitory effect on the covalent binding of an initiating dose of 7,12-dimethylbenz-[a]anthracene (DMBA) to DNA at 24 hr, but CPT post-treatments remarkably inhibit stimulations of DNA synthesis caused by the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) at 16 hr and a carcinogenic dose of DMBA at 7 days. CPT is a much more potent inhibitor if it is applied 10-14 hr after TPA or 4-6 days after DMBA, when DNA synthesis starts being stimulated after the periods of early inhibition caused by TPA and DMBA. When applied 12 hr after the tumor promoter, the ability of 3-3,000 nmol of CPT to inhibit TPA-stimulated DNA synthesis at 16 hr is dose-dependent. A single dose of 500 nmol of CPT inhibits the entire time course for the stimulation of DNA synthesis observed 16-64 hr after TPA. CPT also reduces the various DNA responses to chronic TPA treatments and structurally different non-TPA-type tumor promoters. CPT may indirectly decrease the ornithine decarboxylase-inducing activity of multiple TPA treatments because it can inhibit the stimulation of RNA synthesis by this compound. However, CPT fails to alter TPA-stimulated hydroperoxide production in relation to its inability to inhibit TPA-stimulated protein synthesis. On an equal dose basis, topotecan and 10-hydroxycamptothecin are more and less effective than CPT, respectively, whereas 10,11-methylenedioxycamptothecin is much more potent than its parent compound at inhibiting the DNA response to TPA. A single dose of 400 nmol of CPT has no effect on tumor initiation when applied 4 hr before or 1 hr after a single subcarcinogenic dose of DMBA. In contrast, 400 nmol of CPT chronically applied 1 hr before or 24 hr after each treatment with TPA remarkably inhibits the complete tumor-promoting activity of this agent. CPT post-treatments also inhibit the respective activities of TPA and mezerein in the 1st and 2nd stages of skin tumor promotion.

Splice variants of rat TR4 orphan receptor: differential expression of novel sequences in the 5'-untranslated region and C-terminal domain

The use of rapid amplification of 5'-cDNA ends-PCR yielded two novel sequences for the rat orphan receptor, TR4, representing heterogeneity on the 5'-untranslated region. Genomic structure analysis revealed that the 5'-untranslated region of the longer messenger RNA fragment, rTR4-1, contained three exons, alpha, beta, and gamma. The skipping of exon gamma gave rise to rTR4-2, indicating that rTR4-1 and rTR4-2 are products of alternative splicing. We isolated another novel rat TR4 splice variant, rTR4-NS, which was found to diverge from rTR4-2 at codon 504. rTR4-NS contained an unspliced intronic sequence with in-frame codons for eight amino acids followed by a termination codon. The three TR4 messenger RNA variants were differentially expressed. rTR4-NS appeared to be a rare transcript found in limited areas of the brain. In situ hybridization detect prominent TR4 signals in brain areas known to be involved in stress response. In cerebellar granule cells, the rise in TR4 expression correlated with the progression of neuronal maturation. N-Methyl-D-aspartate treatment triggered a marked increase in TR4 expression. These results suggest a possible role for TR4 in neuronal differentiation.

Characterization of the antitumor-promoting activity of camptothecin in SENCAR mouse skin

(+)-Camptothecin (CPT), a topoisomerase I inhibitor specifically toxic toward S phase cells, was tested topically for its ability to inhibit skin tumor initiation by 7,12-dimethylbenz[a]anthracene (DMBA) and complete tumor promotion by 12-0-tetradecanoylphorbol-13-acetate (TPA) in SENCAR mice. Even though CPT does not prevent the covalent binding of a subcarcinogenic dose of DMBA to DNA, it enhances early inhibition of DNA synthesis caused by this initiator and may decrease the essential role of DNA replication in tumor initiation. Indeed, CPT (400 nmol) applied 4 h before or 1 h after DMBA inhibits the yield, but not the incidence, of skin tumors initiated by this compound. Moreover, because it inhibits TPA-stimulated DNA synthesis at 16 h when applied 12 h after the tumor promoter, CPT partially decreases tumor initiation when DMBA is applied 16 h after a TPA pretreatment. CPT (400 nmol) applied 1 h before or 4, 12, 24 or 48 h after each promotion treatment with TPA remarkably inhibits the incidence and yield of skin tumors promoted by this agent. CPT delays and inhibits promotion of skin tumors the most when applied 12-24 h after each TPA treatment, at times when it can block the stimulation of DNA synthesis that follows the period of early inhibition caused by TPA. The ability of post-treatments with 25, 100 and 400 nmol CPT to inhibit skin tumor promotion is dose dependent. In the TPA (stage I)-mezerein (stage 2) protocol CPT (400 nmol) post-treatment inhibits both the first and second stages of tumor promotion, related to its ability to decrease the DNA and ornithine decarboxylase responses required for stages 1 and 2 respectively. The classic model of multistage skin carcinogenesis, therefore, may be valuable to determine if novel CPT analogs are more effective than their parent compound at inhibiting tumor initiation, promotion and progression.

Immunisation of mice using Salmonella typhimurium expressing human papillomavirus type 16 E7 epitopes inserted into hepatitis B virus core antigen

Live vaccines based on BRD509, an attenuated S. typhimurium (aroA, aroD) strain, were constructed that directed the expression of hepatitis B core antigen particles (HBcAg) (BRD969) or HBcAg harbouring human papillomavirus type 16 E7 protein sequences (BRD974), under the control of the in vivo inducible nirB promoter. These strains were used to orally or intravenously immunise different inbred mouse strains and humoral, secretory and cellular anti-E7 and anti-HBcAg responses were monitored. Both BRD969 and BRD974 induced anti-HBcAg humoral IgG responses following oral or intravenous immunisation of B10 mice, although responses were higher in BRD969 immunised animals. IgG subclass analysis revealed a predominantly IgG2a response in these animals. BRD974, but not BRD969, induced anti-E7 humoral IgG responses. Anti-HBcAg (BRD969 and BRD974) and anti-E7 (BRD974) IgA responses were detected in the intestines of orally immunised mice. Anti-Salmonella but not anti-HBcAg or anti-E7 T helper cell responses were detected in mice immunised with BRD509, BRD969 and BRD974. Thus Salmonella vaccine strains can be used to efficiently deliver HBcAg and E7 epitopes to the mucosal and systemic immune systems.