Evaluation of the Effects of Anti-PD-1 Therapy on Triple-Negative Breast Cancer in Mice by Diffusion Kurtosis Imaging and Dynamic Contrast-Enhanced Imaging

BACKGROUND

The monitoring of immunotherapies is still based on changes in the tumor size in imaging, with a long evaluation period and low sensitivity.

PURPOSE

To investigate the effectiveness of diffusion kurtosis imaging (DKI) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in assessing the therapeutic efficacy of anti-programmed death-1 (PD-1) therapy in a mouse triple negative breast cancer (TNBC) model.

STUDY TYPE

Prospective.

ANIMAL MODEL

A total of 54 BALB/c mouse subcutaneous 4 T1 transplantation models of TNBC.

FIELD STRENGTH/SEQUENCE

A 3.0-T; turbo spin echo (TSE) T2-weighted imaging, DKI with seven b values (0, 500, 1000, 1500, 2000, 2500, and 3000 sec/mm² ) and T1-twist DCE acquisition series.

ASSESSMENT

DKI and DCE-MRI parameters were evaluated by two radiologists independently. Regions of interest (ROIs) were drawn manually on the maximum cross-sectional area of the lesion; care was taken to avoid necrotic areas. The tumor cell density, the CD45 and CD31 levels were analyzed by two pathologists.

STATISTICAL TESTS

The two-tailed unpaired t-test, Mann-Whitney U test, Fisher's exact test and Pearson correlation coefficient were performed. A P < 0.05 was considered statistically significant.

RESULTS

The apparent diffusion coefficient (ADC), mean diffusivity (MD), K_trans and K_ep values were significantly different between the two groups at each time point after treatment. There were significant differences in the mean kurtosis (MK) and V_e values between the two groups at 5 and 10 days after treatment but no significant differences at 15 days (P = 0.317 and 0.183, respectively). The ADC and MD values were significantly correlated with tumor cell density (ADC, r = -0.833; MD, r = 0.890) and the CD45 level (ADC, r = 0.720; MD, r = 0.718). The K_trans and K_ep values were significantly correlated with the CD31 level (K_trans , r = 0.820; K_ep , r = 0.683).

DATA CONCLUSION

DKI and DCE-MRI could reflect the changes in tumor microstructure and tumor tissue vasculature after anti-PD-1 therapy, respectively.

LEVEL OF EVIDENCE

1 TECHNICAL EFFICACY: Stage 4.

[Otologic disorders and management strategies in Turner syndrome]

Objective: To analyze the incidence and risk factors of otologic disorders in patients with Turner syndrome (TS), so as to provide management strategies for ear health. Methods: This study is a prospective study based on questionnaires and a cross-sectional study. The TS patients who visited our hospital from 2010 January to 2021 March were included (A total of 71 patients with TS were included in this study. the age of TS diagnosed was 3- to 11-year-old, age of visiting ENT department was 4- to 27-year-old) and the incidence of otologic diseases in different age groups was investigated by questionnaires. The cross-sectional study included ear morphology and auditory function assessment, and further analysis of the risk factors that related to ear disease. Prism was used for data analysis. Results: The investigation found that the incidence of acute otitis media in patients aged 3-6 and 7-12 years was higher than that of patients over 12 years old, which was 33.8%(24/71), 42.9%(30/70)and 23.5%(8/34), respectively; 21.1% (15/71) of patients were recurrent acute otitis media in patients aged 3-6 years, and about 46.6% (7/15)of them persisted beyond 6-year. The prevalence of otitis media with effusion in the three groups was 32.4%(23/71), 34.3%(24/70)and 38.2%(13/34), respectively; the recurrence rate of tympanocentesis was 100%(7/7), 42.9%(3/7)and 50.0%(1/2), which was significantly higher than that of grommet insertion. For age groups of 3-6 and 7-12 years, the prevalence of acute otitis media and secretory otitis media was lower in the X chromosome structure abnormal patients; while for patients older than 12 years, otitis media with effusion was the highest prevalence in Y-chromosome-containing karyotypes. In addition, the prevalence of acute otitis media and otitis media with effusion in patients with other system diseases were increased significantly. A cross-sectional study found that 7.0% (5/71)of the lower auricular, 4.2% (3/71)of the external auditory canal narrow, and 38.0% (27/71)of the tympanic membrane abnormality. 35.2%(25/71) had abnormal hearing, including 17 cases of conductive deafness, 6 cases of sensorineural hearing loss, and 2 cases of mixed deafness. The rest of the patients had normal hearing, but 6 of them had abnormalities in otoacoustic emission. Eustachian tube function assessment found that the eustachian tube dysfunction accounted for 38%(27/71). Hearing loss and abnormal Eustachian tube function were not significantly related to karyotype(Chi-square 2.83 and 2.84,P value 0.418 and 0.417), but significantly related to other system diseases(Chi-square 13.43 and 7.53,P value<0.001). Conclusions: The incidence of TS-related otitis media and auditory dysfunction is significantly higher than that of the general population. It not only occurs in preschool girls, but also persists or develops after school age. Accompanied by other system diseases are risk factors for ear diseases. Clinicians should raise their awareness of TS-related ear diseases and incorporate ear health monitoring into routine diagnosis and treatment.

[Effects of praziquantel isomers on the proliferation and activation of the LX-2 human hepatic stellate cell line]

OBJECTIVE

To compare the effects of levo-praziquantel (L-PZQ) and dextro-praziquantel (D-PZQ) on the proliferation and activation of the human hepatic stellate cell line LX-2 in vitro.

METHODS

LX-2 cells were stimulated with transforming growth factor-β (TGF-β). LX-2 cell proliferation was measured using the CCK-8 assay after 24 h stimulation with 0 to 50 μg/mL concentrations of praziquantel, and the gene and protein expression of type Ⅰ collagen (collagen Ⅰ), type Ⅲ collagen (collagen Ⅲ) and α-smooth muscle actin (α-SMA) was quantified in LX-2 cells using quantitative real-time PCR (qPCR) and Western blotting assays 24 h and 48 h following stimulation with 15 μg/mL praziquantel to detect LX-2 cell activation.

RESULTS

There were significant differences in the survival rate of LX-2 cells between L-PZQ and D-PZQ treatments at all concentrations (F = 6.119 and 79.180, both P values < 0.05). Either L-PZQ or D-PZQ at a concentration of < 30 μg/mL showed no remarkableeffectsonthe LX-2 cell proliferation (both P values > 0.05), and L-PZQ at a concentration of > 50 μg/mL and D-PZQ at a concentration of > 40 μg/mL inhibited the LX-2 cell proliferation (both P values < 0.05), while D-PZQ at concentrations of 40 μg/mL and 50 μg/mL showed greater inhibition on LX-2 cell proliferation than L-PZQ (t = 3.419 and 8.776, both P values < 0.05). There were significant differences in the collagen Ⅰ, collagen Ⅲ and α-SMA expression in LX-2 cells at both transcriptional (F = 21.55, 79.99 and 46.70, all P values < 0.05) and translational levels (F = 20.12, 30.29 and 32.93, all P values < 0.05) among the blank control group, TGF-β stimulation group, L-PZQ treatment group and D-PZQ treatment group. L-PZQ treatment resulted in remarkable inhibition on collagen Ⅲ and α-SMA gene expression in LX-2 cells (both P values < 0.05); however, the treatment showed no remarkable inhibition collagen Ⅰ gene expression or collagen Ⅰ, collagen Ⅲ or α-SMA protein expression in LX-2 cells (all P values > 0.05). In addition, D-PZQ treatment resulted in significant inhibition on collagen Ⅰ, collagen Ⅲ and α-SMA expression in LX-2 cells at both translational and transcriptional levels (all P values < 0.05), and D-PZQ showed higher inhibition on collagen Ⅰ, collagen Ⅲ and α-SMA gene expression in LX-2 cells than L-PZQ (all P values < 0.05).

CONCLUSIONS

Both L-PZQ and D-PZQ inhibit the proliferation and activation of LX-2 cells, and D-PZQ shows a higher inhibitory activity than L-PZQ.

Performance of radiomics models for tumour-infiltrating lymphocyte (TIL) prediction in breast cancer: the role of the dynamic contrast-enhanced (DCE) MRI phase

OBJECTIVE

To systematically investigate the effect of imaging features at different DCE-MRI phases to optimise a radiomics model based on DCE-MRI for the prediction of tumour-infiltrating lymphocyte (TIL) levels in breast cancer.

MATERIALS AND METHODS

This study retrospectively collected 133 patients with pathologically proven breast cancer, including 73 patients with low TIL levels and 60 patients with high TIL levels. The volumes of breast cancer lesions were manually delineated on T2-weighted imaging (T2WI), diffusion-weighted imaging (DWI), and each phase of DCE-MRI, followed by 6250 quantitative feature extractions. The least absolute shrinkage and selection operator (LASSO) method was used to select predictive feature sets for the classifiers. Four models were developed for predicting TILs: (1) single enhanced phase radiomics models; (2) fusion enhanced multi-phase radiomics models; (3) fusion multi-sequence radiomics models; and (4) a combined radiomics-based clinical model.

RESULTS

Image features extracted from the delayed phase MRI, especially DCE_Phase 6 (DCE_P6), demonstrated dominant predictive performances over features from other phases. The fusion multi-sequence radiomics model and combined radiomics-based clinical model achieved the highest predictive performances with areas under the curve (AUCs) of 0.934 and 0.950, respectively; however, the differences were not statistically significant.

CONCLUSION

The DCE-MRI radiomics model, especially image features extracted from the delayed phases, can help improve the performance in predicting TILs. The radiomics nomogram is effective in predicting TILs in breast cancer.

KEY POINTS

• Radiomics features extracted from DCE-MRI, especially delayed phase images, help predict TIL levels in breast cancer. • We developed a nomogram based on MRI to predict TILs in breast cancer that achieved the highest AUC of 0.950.

[Systemic anti-inflammation is the key for the treat-to-target in severe immune-related skin disorders]

Immune-related skin disorders (inflammatory skin diseases and autoimmune diseases) are important diseases in dermatology. Systemic inflammation is the fundamental cause that makes these diseases difficult to control and easy to relapse. The treatment pattern of rheumatic immune diseases could be used as a reference to reach the treat-to-target (T2T) of severe immune/inflammatory skin disorders, thus to reduce systemic inflammatory damage, to effectively control symptoms in the long term, to improve the quality of life, and to help patients back to normal study/work/life status.

[Studies on resistance of Schistosoma to praziquantel XVIII Sensitivity to praziquantel in filial generations of praziquantel-resistant and -sensitive Schistosoma japonicum mixed infections]

OBJECTIVE

To investigate the sensitivity of adult worms of filial generations from praziquantel-resistant and -sensitive Schistosoma japonicum mixed infections to praziquantel.

METHODS

Mice were infected with the cercariae of an experimentally generated praziquantel-resistant S. japonicum isolate [median effective dose (ED₅₀) = 277.4 mg/kg] and a laboratory-maintained praziquantel-sensitive S. japonicum isolate (ED₅₀ = 99.6 mg/kg) at a mixture ratio of 1:1 and 2:1, which was maintained in the laboratory via the mouse-snail cycle for 8 generations. Then, mice were infected with the cercariae of the 8th filial-generation parasite, and grouped 35 days post-infection. Mice in the 5 treatment groups were given praziquantel treatment by gavage at a single oral dose of 37.5, 75, 150, 300 mg/kg and 600 mg/kg, while animals in the control group was administered orally with 2.5% cremophor EL. All mice were sacrificed 14 days post-treatment and adult worms were collected by perfusion of the portal vein. The worm burden reductions and praziquantel ED₅₀ values were calculated. The praziquantel-resistant S. japonicum isolate generated from experimental induction with 12 rounds of praziquantel treatment with sub-curative doses was maintained in the laboratory via the mouse-snail cycle, and mice were infected with the cercariae of the 8th filial-generation parasite. The praziquantel ED₅₀ value against the 8th filial-generation adults was measured.

RESULTS

After mice were infected with the mixture of cercariae of PZQ-resistant and -sensitive S. japonicum isolates at a ratio of 1:1, the praziquantel ED₅₀ was 135.2 mg/kg against the adults of the 8th filial-generation parasite. After mice were infected with the mixture of cercariae of PZQ-resistant and -sensitive S. japonicum isolates at a ratio of 2:1, the praziquantel ED₅₀ was 129.2 mg/kg against the adults of the 8th filial-generation parasite. In addition, the praziquantel ED₅₀ was 208.4 mg/kg against the adults of the 8th filial-generation S. japonicum without the selection pressure of praziquantel.

CONCLUSIONS

Compared with the experimentally induced praziquantel-resistant S. japonicum isolate, the adult worms of the filial-generation S. japonicum show a reduced sensitivity to praziquantel in the same host following infection with the mixture of cercariae of praziquantel-resistant and -sensitive S. japonicum isolates. The adult worms of the filial generation of the praziquantel-resistant S. japonicum isolate without the selection pressure of praziquantel may still maintain the resistance to praziquantel.

[Prevalence of Spirometra mansoni infections in hosts in Jiangsu Province]

OBJECTIVE

To investigate the prevalence of Spirometra mansoni infections in hosts in Jiangsu Province, so as to provide the scientific basis for the management of sparganosis mansoni.

METHODS

From 2018 to 2019, nine counties (cities, districts) were randomly selected from Jiangsu Province as the survey sites, and 100 healthy individuals were randomly selected to perform the serological test of S. mansoni infections and the detection of S. mansoni eggs. The procercoids were detected in the intermediate host Cyclops, and the S. mansoni eggs were identified in the stool samples of the definitive hosts cats and dogs.

RESULTS

The prevalence of S. mansoni human infections was 0 (0/900) in the 9 survey sites of Jiangsu Province, and the sero-prevalence of the specific IgG antibody against S. mansoni was 1.22% (11/900). The positive rate of procercoids was 0.33% (3/900) in Cyclops. In addition, the S. mansoni egg-positive rate was 1.48% (2/135) in cats and dogs.

CONCLUSIONS

Sparganosis mansoni is prevalent in Jiangsu Province. Health education pertaining to the damages of sparganosis mansoni and the route of S. mansoni infections should be improved.

Whole-Lesion Histogram Analysis of the Apparent Diffusion Coefficient as a Quantitative Imaging Biomarker for Assessing the Level of Tumor-Infiltrating Lymphocytes: Value in Molecular Subtypes of Breast Cancer

Purpose

To assess whether apparent diffusion coefficient (ADC) metrics can be used to assess tumor-infiltrating lymphocyte (TIL) levels in breast cancer, particularly in the molecular subtypes of breast cancer.

Methods

In total, 114 patients with breast cancer met the inclusion criteria (mean age: 52 years; range: 29–85 years) and underwent multi-parametric breast magnetic resonance imaging (MRI). The patients were imaged by diffusion-weighted (DW)-MRI (1.5 T) using a single-shot spin-echo echo-planar imaging sequence. Two readers independently drew a region of interest (ROI) on the ADC maps of the whole tumor. The mean ADC and histogram parameters (10^th, 25^th, 50^th, 75^th, and 90^th percentiles of ADC, skewness, entropy, and kurtosis) were used as features to analyze associations with the TIL levels in breast cancer. Additionally, the correlation between the ADC values and Ki-67 expression were analyzed. Continuous variables were compared with Student’s t-test or Mann-Whitney U test if the variables were not normally distributed. Categorical variables were compared using Pearson’s chi-square test or Fisher’s exact test. Associations between TIL levels and imaging features were evaluated by the Mann-Whitney U and Kruskal-Wallis tests.

Results

A statistically significant difference existed in the 10^th and 25^th percentile ADC values between the low and high TIL groups in breast cancer (P=0.012 and 0.027). For the luminal subtype of breast cancer, the 10^th percentile ADC value was significantly lower in the low TIL group (P=0.041); for the non-luminal subtype of breast cancer, the kurtosis was significantly lower in the low TIL group (P=0.023). The Ki-67 index showed statistical significance for evaluating the TIL levels in breast cancer (P=0.007). Additionally, the skewness was significantly higher for samples with high Ki-67 levels in breast cancer (P=0.029).

Conclusions

Our findings suggest that whole-lesion ADC histogram parameters can be used as surrogate biomarkers to evaluate TIL levels in molecular subtypes of breast cancer.

[Study on the factors affecting the degradation of niclosamide in the soil]

OBJECTIVE

To investigate the factors affecting the degradation of niclosamide in the soil, so as to provide the evidence for the assessment of the environmental safety in the field snail control with niclosamide.

METHODS

A high performance liquid chromatography was established for the determination of niclosamide in the field. Then, the degradation of niclosamide was investigated in soils with different moistures (10%, 30%, 50%, 70% and 90%), temperatures [(15 ± 1), (25 ± 1), (35 ± 1) °C], initial concentrations (1, 5, 10 mg/kg) and in sterilized and non-sterilized soils. In addition, the degradation of niclosamide was fitted with the first-order kinetics equation, and the degradation half-life was calculated.

RESULTS

The niclosamide residues gradually decreased over time in soils with different moistures, and a higher rate of degradation was seen in soils with a higher moisture. The degradation half-life of niclosamide reduced from 4.258 d in the soil with a 10% moisture to 2.412 d in the soil with a 90% moisture. The niclosamide residues gradually decreased over time in soils with different temperatures, and a higher rate of degradation was seen in soils with a higher temperature. The degradation half-life of niclosamide reduced from 4.398 d in the soil with a temperature of (15 ± 1) °C to 2.828 d in the soil with a temperature of (35 ± 1) °C. The degradation half-lives of niclosamide were 3.212, 3.333 d and 3.448 d in soils containing niclosamide at initial concentrations of 1, 5 mg/kg and 10 mg/kg, and > 30 d and 3.273 d in sterilized and non-sterilized soils. Multiple linear regression analysis revealed that soil microorganisms (P = 0.010), moisture (P = 0.000) and temperature (P = 0.002) affected the half-life of niclosamide degradation.

CONCLUSIONS

The degradation of niclosamide in soils fits the first-order kinetics equation, and presence of microorganisms, a high temperature and high moisture may accelerate the degradation of niclosamide in the soil.

Magnetic Resonance Imaging (MRI) Phenotypes May Provide Additional Information for Risk Stratification for Encapsulated Papillary Carcinoma of the Breast

Background

Encapsulated papillary carcinoma (EPC) of the breast is a rare entity. EPC can be underappreciated on percutaneous biopsy, which may require additional procedures if invasion is not recognized preoperatively. We aimed to investigate the magnetic resonance imaging (MRI) phenotypes correlated with preoperative pathological risk stratification for clinical guidance.

Materials and Methods

The preoperative MRI scans of 30 patients diagnosed with 36 EPCs in multiple centers between August 2015 and February 2020 were reviewed by two breast radiologists. According to the WHO classification published in 2019, EPCs were classified into two pathological subtypes: encapsulated papillary carcinoma and encapsulated papillary carcinoma with invasion. Clinicopathological analysis of the two subtypes and MR feature analysis were performed.

Results

Evaluation of the MRI phenotypes and pathological subtype information revealed that not circumscribed (P=0.04) was more common in EPCs with invasion than in EPCs. There was a significant difference in the age of patients (P=0.05), and the risk increased with age. The maximum diameter of the tumor increased with tumor risk, but there was no significant difference (P=0.36). Nearly half of the EPC with invasion patients showed hyperintensity on T1WI (P=0.19). A total of 63.6% of the EPC with invasion group showed non-mass enhancement surrounding (P=0.85). In addition, 29 patients (96.7%) had no axillary lymph node metastasis, and only one patient with EPC with invasion had axillary lymph node metastasis. Further pathological information analysis of EPCs showed that higher Ki-67 levels were more common in patients with EPCs with invasion (P=0.04). A total of 29 patients (96.7%) had the luminal phenotype, and one patient with EPC with invasion had the Her-2-positive phenotype.

Conclusion

The margin, age and Ki-67 level were the key features for EPC risk stratification. In addition, these MRI signs, including a larger tumor, non-mass enhancement surrounding and axillary lymph node metastasis, may be suggestive of a high-risk stratification. Therefore, MRI phenotypes may provide additional information for the risk stratification of EPCs.

[Progress of interruption of schistosomiasis transmission in Jiangsu Province]

Schistosomiasis was once heavily endemic in Jiangsu Province. Following the control efforts for several decades, schistosomiasis was almost eradicated in all endemic counties in Jiangsu Province in 1980, and transmission control was achieved in the province in 2011. According to the principle of "implementing the control measures with adaptation to local circumstances and guiding the control programs with classified interventions", an integrated strategy with emphasis on the management of both infectious sources and snails has been recently employed for schitsosomiasis control in Jiangsu Province. In addition, a sensitive and highly effective surveillance system has been built and the application of novel techniques and information construction has been intensified to effectively interrupt the transmission of schistosomiasis in the Province. Transmission interruption of schistosomiasis was achieved in all endemic counties in Jiangsu Province. The paper summarizes the endemic situation of schistosomiasis, progress of schistosomiasis control, and major schistosomiasis control measures implemented during the stage of transmission interruption in Jiangsu Province.

CAFs secreted exosomes promote metastasis and chemotherapy resistance by enhancing cell stemness and epithelial-mesenchymal transition in colorectal cancer

BACKGROUND

Cancer associated fibroblasts (CAFs) are key stroma cells that play dominant roles in tumor progression. However, the CAFs-derived molecular determinants that regulate colorectal cancer (CRC) metastasis and chemoresistance have not been fully characterized.

METHODS

CAFs and NFs were obtained from fresh CRC and adjacent normal tissues. Exosomes were isolated from conditioned medium and serum of CRC patients using ultracentrifugation method and ExoQuick Exosome Precipitation Solution kit, and characterized by transmission electronic microscopy, nanosight and western blot. MicroRNA microarray was employed to identify differentially expressed miRNAs in exosomes secreted by CAFs or NFs. The internalization of exosomes, transfer of miR-92a-3p was observed by immunofluorescence. Boyden chamber migration and invasion, cell counting kit-8, flow cytometry, plate colony formation, sphere formation assays, tail vein injection and primary colon cancer liver metastasis assays were employed to explore the effect of NFs, CAFs and exosomes secreted by them on epithelial-mesenchymal transition, stemness, metastasis and chemotherapy resistance of CRC. Luciferase report assay, real-time qPCR, western blot, immunofluorescence, and immunohistochemistry staining were employed to explore the regulation of CRC metastasis and chemotherapy resistance by miR-92a-3p, FBXW7 and MOAP1.

RESULTS

CAFs promote the stemness, epithelial-mesenchymal transition (EMT), metastasis and chemotherapy resistance of CRC cells. Importantly, CAFs exert their roles by directly transferring exosomes to CRC cells, leading to a significant increase of miR-92a-3p level in CRC cells. Mechanically, increased expression of miR-92a-3p activates Wnt/β-catenin pathway and inhibits mitochondrial apoptosis by directly inhibiting FBXW7 and MOAP1, contributing to cell stemness, EMT, metastasis and 5-FU/L-OHP resistance in CRC. Clinically, miR-92a-3p expression is significantly increased in CRC tissues and negatively correlated with the levels of FBXW7 and MOAP1 in CRC specimens, and high expression of exosomal miR-92a-3p in serum was highly linked with metastasis and chemotherapy resistance in CRC patients.

CONCLUSIONS

CAFs secreted exosomes promote metastasis and chemotherapy resistance of CRC. Inhibiting exosomal miR-92a-3p provides an alternative modality for the prediction and treatment of metastasis and chemotherapy resistance in CRC.

[The effect of pre-operation (125)I seed activity measuring on dose accuracy]

Objective: To measure the activity of (125)I seed and compare the dose difference of ten patients treated with seed implantation in pre-plan with actual seed activity and calibrate activity. Method: The activity of 100 seeds from company A and B was measured with a well-type ionization chamber 1 day before operation and named group A and B. The activity of two groups was compared and the error between actual and calibrate activity (22.2 MBq, group C) was calculated. Ten patients implanted with (125)I seeds from November 1 st to 30 th, 2017, solstice 30 were selected in Hebei General Hospital. Firstly, pre-plans were designed with 22.2 MBq, prescribed dose were 100-140 Gy. The dose parameters of 90% volume absorbed dose (D(90)), 150% volume fraction (V(150)) and 100% volume fraction (V(100)) were calculated. Then changed 22.2 MBq to actual activity of group A and B, calculated the dose parameters above again. Then dose parameters of D(90), V(150), V(100) in group C were compared with those in group A and B respectively. Result: The actual activity 1 day before the operation was(22.6±0.7)and(23.9±0.9)MBq in group A and B respectively. Compared with 22.2 MBq, the difference was statistically significant(t=5.7, P<0.05 and t=19.2, P<0.05), and the activity error of group B was greater than 5%. The D(90) of group A, B and C were (124.3±9.7) , (131.2±10.2) and (121.9±9.5) Gy respectively.The V(150) were 58.4%±9.4%, 63.7%±8.9% and 56.5%±9.2% respectively. The V(100) were 88.9%±5.0%, 92.0%±4.1%, 88.1%±5.2% respectively.The difference of D(90) between calibrate activity(group C) and actual activity(group A and B) were statistically significant (t=40.2, P<0.05 and t=40.3, P<0.05). The difference of V(150) between group C and group A and B were statistically significant (t=7.5, P<0.05 and t=24.7, P<0.05). The difference of V(100) between group C and group A and B were statistically significant (t=6.6, P<0.05 and t=7.3, P<0.05). Conclusion: There is difference between the actual activity and calibration activity. The difference affects the dose parameters in pre-plan.The seed activity should be measured before operation strictly and the pre-plan should be designed with the actual activity.

Growth performance, rumen fermentation, bacteria composition, and gene expressions involved in intracellular pH regulation of rumen epithelium in finishing Hu lambs differing in residual feed intake phenotype

The objective of this study was to evaluate the effect of residual feed intake (RFI) on rumen function in finishing lambs. A total of 60 male Hu lambs (average initial BW = 25.2 ± 2.5kg) were used and were offered a pelleted high-concentrate diet, of which the forage to concentrate ratio was 25:75. Individual feed intake was recorded over a period of 42 d, then 10 lambs with the lowest RFI and the highest RFI were selected, respectively. The rumen fluid used for fermentation variables and relative abundance of bacteria measurement was obtained on d 10 and 20 after RFI measurement. At the end of this experiment, the selected lambs were slaughtered and rumen epithelium and liver tissues were collected for RNA extraction. Low-RFI lambs had lower ( < 0.01) DMI and greater ( < 0.05) G:F than the high-RFI ones, while the RFI groups did not differ in ADG and BW ( > 0.05). Additionally, RFI was positively ( = 0.57; < 0.01) correlated with DMI and negatively ( = -0.53; < 0.05) correlated with G:F. Total VFA and individual VFA decreased ( < 0.05) over time. The concentrations of total VFA, acetate, valerate, isobutyrate, isovalerate, and rumen pH ( > 0.05) were not affected by RFI classification. Nonetheless, low-RFI group lambs had a greater ( < 0.05) concentration of propionate, a lower ( < 0.05) concentration of butyrate, and a lower ( < 0.05) acetate to propionate ratio compared with the high-RFI group. There was a significant ( < 0.05) effect of RFI on the relative abundance of and . The relative abundance of , , and decreased ( < 0.05) over time in high-RFI group. And the relative abundance of in high-RFI group was greater ( < 0.05) than its low-RFI counterpart. Furthermore, RFI had no effect ( > 0.05) on gene expression associated with intracellular pH regulation (, , , , , , , and ) in rumen epithelium and β-hydroxybutyrate metabolism () in both rumen epithelium and liver tissues. In conclusion, even though low-RFI lambs had lower DMI, however, the number of was lower. Additionally, there was no difference in gene expressions level associated with intracellular pH regulation in rumen epithelium between RFI groups.

Impact of the South-to-North Water Diversion Project on the transmission of Schistosoma japonicum in China

The South-to-North Water Diversion Project (SNWDP) is currently the key, national, water-conservation project in China, designed to optimise the use of water resources and relieve the water shortages in the north of the country. As one of the main water intakes for the project, that of the Eastern Route Scheme (ERS), is a breeding site for Oncomelania hupensis (the intermediate host of Schistosoma japonicum), there is concern that the snail may be carried far to the north, in the water passing through the project. To see if they could survive and breed to the north of their current range in China, O. hupensis were collected in marshland near Nanjing City and transferred to cages, on the banks of fish ponds, in the cities of Zhenjiang (in Jiangsu province, at 32 degrees 10'N), Xuzhou (in the same province but at a latitude of 34 degrees 23'N) and Jining (in Shandong province, at 35 degrees 23'N). Except over the first 6 months in Xuzhou, the snails moved north of their natural distribution did not survive and reproduce as well as those in Zhenjiang, and all those transferred to Jining died out within 1 year. Although the snail populations in Xuzhou survived for 7-8 years and retained their infectivity to S. japonicum, histological and histochemical studies revealed abnormalities in the reproductive organs of these snails. It is concluded that, unless global warming significantly increases the minimum winter temperatures in northern China, the SNWDP is unlikely to result in the northward spread of schistosomiasis japonica.

Diagnostic clues to megaloblastic anaemia without macrocytosis

Masking of the macrocytic expression of megaloblastic anaemia (MA) by coexisting thalassaemia, iron deficiency and chronic illness has been widely reported. We described the haematological and clinical features of 20 Chinese patients with MA presenting with mean corpuscular volume (MCV) < or =99 fl, and analysed the steps leading to the final diagnosis of MA with concomitant thalassaemia trait (n = 11), thalassaemia trait and iron deficiency (n = 3), iron deficiency (n = 4) and chronic illness (n = 2). We also compared the haematological characteristics of this group of patients with a group of normocytic anaemic patients without vitamin B(12)/folate deficiency, and identified certain laboratory information useful for differentiating the two groups. Statistically significant parameters included the mean values of haemoglobin, MCV, red cell distribution width (RDW), reticulocyte index, platelet count and serum bilirubin. All provided clues to maturation disorders within the marrow. A decision flowchart for the diagnosis of MA without macrocytosis was proposed. In the studied population, by using the parameters of haemoglobin <10 g/dl, MCV 80-99 fl, RDW > or = 16% and reticulocyte index < or = 2% as indicators, there was a 58% chance that a patient had MA without macrocytosis if he/she had all the four indicators, and a 2.2% chance of having it if he/she did not have these indicators. We emphasized the importance of including peripheral blood smear examination in the diagnostic procedures for such patients, as well as the importance of paying attention to patients' medical history, racial background and previous MCV value.

Antibody isotype responses to Schistosoma japonicum antigens in subjects from a schistosomiasis area with repeated praziquantel chemotherapy compared with a new endemic zone in Hunan Province, P.R. China

To demonstrate the dynamics of specific antibody isotypes against schistosome adult worm (AWA) and soluble egg (SEA) antigens, we evaluated (in 1999-2000) 112 subjects infected with Schistosoma japonicum from 2 regions of Hunan Province, China. Fifty-eight subjects were from Area A, a well-known endemic area with repeated chemotherapy. Area B (n = 54) is a new endemic focus in another part of the same province. Serum samples were collected prior to praziquantel (PZQ) chemotherapy, and at 2 and 12 months post-treatment. IgM, IgA, IgG, IgG2, IgG4 and IgE antibodies to AWA and SEA were measured by quantitative enzyme-linked immunosorbent assay (ELISA). Pre-treatment antibody isotype levels from Area A, except IgA against AWA and SEA, were significantly higher than those from Area B. In response to chemotherapy, most antibody isotype levels fell or remained stable. However, in Area A there was a significant increase in the IgA, IgE and IgG4 responses to AWA 2 months after PZQ--which fell to approach pre-treatment levels by 12 months. A similar response was seen in Area B with IgE and IgG4 to AWA. Levels of all AWA-specific IgE and IgG4 were significantly higher in subjects from Area A compared with Area B at all time-points. AWA-IgE levels demonstrated significant linear correlations with age and number of previous PZQ treatments in Area A only. All SEA-specific isotypes in both areas fell significantly in response to treatment--except IgE, which remained stable in both area. All SEA-specific isotype levels (except IgA) were significantly higher from Area A at baseline. This significant difference was maintained through 12-months follow-up for IgE, IgG2 and IgG4 only. This study suggests that multiple episodes of schistosome infection may be required to generate antibody isotype levels that have been associated with resistance to re-infection in other studies. Further, a surrogate marker of successful chemotherapy (AWA-IgG4) performed less effectively in patients with previous treatment courses.

Biological characteristics of praziquantel-resistant and -susceptible isolates of Schistosoma mansoni

If there is a change in the biological characteristics of schistosomes associated with the development of resistance to praziquantel, this could affect the transmission and pathology of the diseases they cause. To investigate this possibility, the host-parasite relationships of five praziquantel-resistant and five praziquantel-susceptible isolates of Schistosoma mansoni were compared in Biomphalaria glabrata snails and outbred CD(1) albino mice. Whether praziquantel-resistant or -susceptible, all the laboratory-selected isolates gave similar results in B. glabrata. However, the snails infected with any of three field-collected isolates from Senegal, each of which has been shown to be praziquantel-resistant, shed fewer cercariae and survived longer than the snails infected with the drug-susceptible or laboratory-selected, drug-resistant isolates. There were no differences between isolates in terms of their infectivity to mice. However, mice infected with any of four of the five drug-resistant isolates shed more eggs in their faeces than mice carrying the drug-susceptible parasites, and mice infected with any of the resistant isolates also had larger numbers of eggs in their tissues. Although granuloma sizes were generally similar for all isolates, the praziquantel-resistant isolates may be more pathogenic in mice than the susceptible ones because of their relatively high egg productions.

Susceptibility of Schistosoma japonicum to praziquantel in China

To look for possible evidence of the development of resistance in Schistosoma japonicum to praziquantel, we conducted a field study in China. During the non-transmission period of schistosomiasis a random sample of 2860 individuals from six villages in three provinces of China were examined using a parasitological stool examination. Of the 372 stool-positive subjects, 363 subjects were treated with a single oral dose of 40 mg/kg of praziquantel. Six to Seven weeks after treatment, of 334 subjects examined using the same stool examination, stool-negative results were found in 319 patients which represents a 95.5% parasitologic cure rate. Fifteen subjects still excreting eggs were treated a second time with the same dose of praziquantel. All stool samples, including those from participants re-treated with praziquantel, were re-examined 12 weeks after the first treatment and no stool-positive subjects were found. The results indicate that there was no evidence for reduced susceptibility of S. japonicum to praziquantel despite its extensive use in the main endemic areas of China for more than 10 years. The in vitro responses to praziquantel of cercariae, miracidia and eggs of S. japonicum compared with S. mansoni demonstrate that the cercariae, miracidia and eggs of S. japonicum are more sensitive to praziquantel than those of S. mansoni. More sensitive worms would be less likely to develop resistance and this could explain why no evidence for resistance was found in S. japonicum in China.

In vitro responses of praziquantel-resistant and -susceptible Schistosoma mansoni to praziquantel

The resistance status of five praziquantel-susceptible and five praziquantel-resistant isolates was confirmed by chemotherapy in CD(1) mice with 3 x 200mg/kg micronised praziquantel. Micronised praziquantel had higher efficacy than two other praziquantel formulations (prepared without milling). The five resistant isolates were less responsive to praziquantel than the five susceptible isolates (59-74% reduction in worm burden in resistant isolates compared with 92-100% in susceptible isolates). Observations were made on the in vitro responses of different stages of 10 isolates to praziquantel. There were different in vitro responses to praziquantel at the egg, miracidial, cercarial and adult stages of Schistosoma mansoni between praziquantel-resistant and praziquantel-susceptible isolates. There were differences in the response of resistant and susceptible isolates following exposure of freshly hatched miracidia to 10(-6)M praziquantel for 1 min and observing the percent change in shape. Using this test it should be possible to determine whether failed therapy in patients infected with S. mansoni is due to the presence of praziquantel-resistant worms. Similarly, by exposing freshly shed cercariae to 4 x 10(-7)M praziquantel and observing the percent of tail shedding over 80 min it should be possible to monitor for the presence of praziquantel-resistant worms in snails collected in the field.

Efficacy of praziquantel against Schistosoma japonicum: field evaluation in an area with repeated chemotherapy compared with a newly identified endemic focus in Hunan, China

This study conducted in 1999/2000 was designed to evaluate the efficacy of praziquantel against Schistosoma japonicum in an area with repeated chemotherapy (Area A) compared with a newly identified endemic focus (Area B) in Hunan Province, China. The population size was 2015 and 2180 in Areas A and B, respectively, of which 1129 and 1298 subjects received stool examination. A total of 230 subjects were identified by the Kato-Katz technique (4 smears per person) as being infected with S. japonicum, 124 in Area A (prevalence 11%) and 106 in Area B (prevalence 8.2%). They were treated with a single oral dose of praziquantel (40 mg/kg) in the non-transmission season. A follow-up stool examination was made 50 days after treatment. Among the 220 cases followed, 22 were found stool-egg-positive, with an overall cure rate of 90%, and 99% reduction of infection intensity (eggs per gram stool). No significant difference was found in cure rates between the 2 areas (89.7% vs 90.3%). The efficacy of the drug in the area with repeated chemotherapy was not significantly different from that in the newly identified endemic focus. This study, therefore, suggests that the efficacy of praziquantel against S. japonicum has not changed in the Dongting Lake region after more than 14 years of mass chemotherapy, and there is no evidence of tolerance or resistance of S. japonicum against praziquantel.

Molecular cloning and targeting of a fibrillarin homolog from Arabidopsis

Fibrillarin is a nucleolar protein known to be involved in the processing of ribosomal RNA precursors. We isolated AtFbr1, a cDNA encoding a homolog of fibrillarin in Arabidopsis. The cDNA is 1.2 kb in size and encodes a polypeptide of 310 amino acid residues with a molecular mass of 33 kD. AtFbr1 is expressed at high levels in the flower and root tissue and at a slightly lower level in leaf tissue, whereas it was nearly undetectable in siliques. Expression of AtFbr1 was compared with that of the FLP (fibrillarin-like protein) gene identified by the Arabidopsis genome project. Abscisic acid treatment resulted in the down-regulation of the expression of both AtFbr1 and FLP genes in seedlings, although the degree of suppression was higher for FLP than for AtFbr1. In addition, the expression level of FLP decreased with the age of the seedlings, whereas AtFbr1 did not exhibit any detectable change. The subcellular localization of AtFbrl was studied with an in vivo targeting approach using a fusion protein, and was found to be correctly targeted to the nucleolus in protoplasts when expressed as a green fluorescent fusion protein (GFP). Deletion experiments showed that the N-terminal glycine- and arginine-rich region is necessary and sufficient to target AtFbr1 to the nucleolus.

Tandemly repeated genomic sequence demonstrates inter- and intra-strain genetic variation in Schistosoma japonicum

Genetic variability within and among four geographical strains of Schistosoma japonicum was examined using a novel repetitive element. The element, termed Sirh1.0, was isolated from genomic DNA of a Philippine strain of S. japonicum using a combination of restriction fragment PCR and band-stab PCR. Sjrh1.0 is a tandemly repeated element, the sequence of which appears to be species-specific, in that it hybridized to DNA from S. japonicum but not to DNA from S. mansoni. Its sequence does not match previously deposited sequences in GenBank. When employed as a probe in Southern hybridization analysis, radiolabelled Sjrh1.0 revealed sex-specific and strain-specific differences in genomic DNA of individual worms. We also found individual genetic variation within geographical isolates of the Asian schistosome.

Non-tuberculous mycobacterial keratitis: a study of 22 cases

AIM

To investigate causes and clinical findings of non-tuberculous mycobacterial keratitis, and to study its response to topical antibiotic therapy and surgical extirpative keratectomy.

METHOD

A single centre, retrospective review of 22 patients with non-tuberculous mycobacterial keratitis seen in a 3 year period. Laboratory diagnoses were established with Ziehl-Nielsen acid fast staining and Löwenstein-Jensen cultures.

RESULTS

In 20 patients (91%), there was an antecedent history of foreign body eye trauma (18 patients) or elective surgery (two patients). There were 19 cases of Mycobacterium chelonei, and three of M fortuitum. Clinical signs included epithelial defects, satellite or ring stromal infiltrates, crystalline keratopathy, and hypopyon. For topical antibiotic therapy, 20 patients received amikacin, while one patient received rifampin and another received ciprofloxacin, each in accordance with the results of the in vitro drug sensitivities. An extirpative keratectomy was performed in 15 cases; four of these cases additionally required a temporary conjunctival flap in order to finally eradicate the infection. At the end of the follow up period (median 18 months; range 3 months to 3 years) all eyes were stable and free of infection, with 19 (86%) having final visual acuities of 20/200 or better.

CONCLUSION

Early clinical recognition and prompt laboratory diagnosis, together with aggressive topical antibiotic therapy and early keratectomy, may shorten morbidity and improve the clinical outcome of non-tuberculous mycobacterial keratitis.

Neglect of childhood strabismus: Keelung Ann-Lo Community ocular survey 1993-1995

Strabismus is a major cause of amblyopia. Parents not aware of the adverse outcome of untreated strabismus is thought to be a major reason of their affected child not being discovered earlier. An ocular survey was therefore conducted to examine the relative neglect of strabismus by the public, using myopia as a reference eye disorder. Specific objectives included estimating the prevalence of these ocular diseases, comparing the self-reported rate to the test-based rate, and investigating how much parents knew about these ocular diseases. Between 1993 and 1995, 862 elementary students in the first, third, and sixth grade at Keelung Ann-Lo Community were screened. The prevalence of manifest strabismus was 1.62% (95% CI = 1.19% approximately 2.05%). Of those with strabismus, three (21.4%) knew that they had strabismus. Neither the prevalence nor the self-known proportion of strabismus changed substantially with school grade, suggesting that the majority of strabismus afflicted children remain unrecognized during their elementary school years. The amblyopia proportion in those with tropia was 42.9% and reduced to 21.5% after abnormal refractive error was excluded. Of six knowledge statements about each ocular disorder, parents answered 2.13 (SD = 1.40) strabismus statements correctly, which was significantly less than their response on myopia statements (4.32 with SD = 1.24) (p < .0001). Onset age of strabismus was the question answered least correctly, implying that parents are not aware of the timing of treating strabismus. Our findings suggest that childhood strabismus was neglected by the public before the implementation of National Health Insurance (NHI). Should a similar study continued to be conducted in the future, the efficacy of NHI in the early recognition and treatment on childhood strabismus can be evaluated.

Visual loss as the initial presentation of nasopharyngeal carcinoma

Eye symptoms and cranial nerve involvement are rather common in nasopharyngeal carcinomas, but early invasion of the optic nerve is very rare. Two cases of nasopharyngeal carcinoma that presented initially with visual loss are reported.

The molluscicidal activity of Phytolacca dodecandra. I. Location of the activating esterase

A number of methods have been used to extract molluscicidal saponins from the dried berries of Phytolacca dodecandra. The potency of the extract has been determined to depend on the release of an enzyme found only in the seed and breaking the seed is critical to the extraction process. The enzyme is inactivated by heat of alcohol. The highest potency extract is made from a cold water extraction of finely ground dried berries.

Drug resistance in schistosomiasis: a review

Drug resistance associated with the treatment of human schistosomiasis appears to be an emerging problem requiring more attention from the scientific community than the subject currently receives. Drug-resistant strains of Schistosoma mansoni have been isolated by various investigators as a result of laboratory experimentation or from a combination of field and laboratory studies. Review of this data appears to indicate that the lack of susceptibility observed for some of the isolated strains cannot be ascribed solely to previous administration of antischistosome drugs and thus further studies are required to elucidate this phenomena. Strains of S. mansoni have now been identified from Brazil which are resistant to oxamniquine, hycanthone and niridazole; from Puerto Rico which are resistant to hycanthone and oxamniquine; and from Kenya which are resistant to niridazole and probably oxamniquine. Strains derived by in vitro selection and resistant to oxamniquine and possibly to oltipraz are also available. All of these strains are currently maintained in the laboratory in snails and mice, thus providing for the first time an opportunity for indepth comparative studies. Preliminary data indicates that S. haematobium strains resistant to metrifonate may be occurring in Kenya. This problem could poise great difficulty in the eventual development of antischistosomal agents. Biomphalaria glabrata from Puerto Rico and Brazil were found to be susceptible to drug-resistant S. mansoni from each country.

Surgical results of second-attempt radial keratotomy

The safety, efficacy, and stability of second-attempt radial keratotomy were evaluated in 20 eyes of 12 patients from September 1, 1982, to August 31, 1983. The average amount of refractive error change was 1.89 diopters with 1.38 diopters of corneal curvature flattening. The effect of the second-attempt operation was about 60% that of the first-attempt operation. No significant surgical complications were observed in this study.

Analysis of intraocular lens power calculation

We performed an analysis of ocular biometry and intraocular lens (IOL) power calculation on 100 eyes that had anterior chamber IOL implantation during 1981 and 1982. Various methods of calculating the IOL power were used, including the standard lens power, presurgical basic refraction, Fyodorov's formula, Colenbrander's formula, Binkhorst's formula, and the SRK formula. In addition, we took the median value of these calculated results as the median power in selecting an appropriate IOL power. The postoperative refraction and actually implanted IOL power were used to determine the IOL power needed for emmetropia. Our regression analysis of the predicted IOL power and power actually needed for emmetropia showed that the methods of standard power and presurgical basic refraction were unreliable while the rest were of satisfactory accuracy. Among the latter, all the predicted IOL powers based on the biometric data had almost the same coefficient of determination and standard error of estimate. However, with the SRK formula and the median power the values of the regression line were closest to the ideal value. With the regression analysis, the accuracy of predicted IOL power from theoretical formulas was comparable to that of the SRK regression formula.

Transplantation of Schistosoma japonicum daughter sporocysts in Oncomelania hupensis

Schistosoma japonicum daughter sporocysts obtained from infected Oncomelania hupensis hupensis were successfully transplanted to parasite-free O. hupensis hupensis. Survival and infection rates of recipient snails were 80% and 75% respectively. Intramolluscan development of transplanted daughter sporocysts in recipient snails appears to proceed in a similar manner as those reported for transplanted S. mansoni and S. haematobium in their respective snail intermediate hosts. Complete colonization of the digestive gland of recipient snails by sporocysts was observed 80 days after transplantation. Cercarial production during a 10-day observation from recipient snails was characterized by periods of high and low and irregular daily emissions. The average daily cercarial production was 150 per snail. Cercariae produced by recipient snails were infective to mice. Of those cercariae exposed to mice, approximately 30% developed to adult schistosomes. These results have definitive utility in the maintenance of S. japonicum in the laboratory.

Cultivating Lithoglyphopsis aperta Temcharoen, a new snail host for Schistosoma japonicum, Mekong strain

Lithoglyphopsis aperta Temcharoen, a new intermediate host for Schistosoma japonicum, Mekong strain, was cultivated successfully through the F2 generation with the use of a petri dish aquarium provided with mud and alga. The incubation period of eggs was about 4 weeks; the young grew to maturity in 16 to 20 weeks; egg-laying followed about 6 to 8 weeks later, the cycle taking roughly 6 months. The husked eggs were deposited exclusively at the edge and wall of the aquarium. Eggs were hemispherical and with the husks were between 0.37 and 0.43 mm in diameter. The newly hatched young were only 0.24 mm in shell length and the full-grown snails were 3.11 to 3.36 mm long. Logarithmic growth began between the 12th and 14th weeks.