Clinical features of retinal amyloid angiopathy with transthyretin Gly83Arg variant.

AIM: To report on the clinical features of patients with retinal amyloid angiopathy (RAA) who were identified to be caused by the transthyretin (TTR) Gly83Arg variant. METHODS: Case series of five patients diagnosed with RAA was collected at Affiliated Hospital of Zunyi Medical University from January 2010 to December 2021. The clinical features, therapeutic strategies, and prognoses of all patients were reviewed. RESULTS: Five patients with a mean age of 52.00±7.23y were diagnosed as RAA. These patients were previously diagnosed with hereditary transthyretin amyloidosis caused by the TTR Gly83Arg variant. Vitreous opacity was found in all 10 eyes, and 7 eyes developed RAA 2 to 20y after the onset of hereditary transthyretin amyloidosis. The clinical manifestations were recurrent vitreous hemorrhage in 2 eyes (29%), neovascular glaucoma in 2 eyes (29%), and iris neovascularization in 1 eye (14%). Microangioma lesions were found in all affected eyes that underwent fundus fluorescein angiography (FFA) in this group of cases, and the incidence of the retinal non-perfusion area was 67%. Although no cases of retinal neovascularization were found, the prognosis of visual acuity was not ideal. CONCLUSION: This is the first report of RAA in patients with the TTR Gly83Arg variant. Complications such as RAA and glaucoma will seriously affect the visual prognosis of patients. Thereafter, regular ophthalmic follow-up of patients with hereditary transthyretin amyloidosis is essential. And FFA after vitrectomy is very important, which can help ophthalmologists detect RAA earlier and treat it in time.

Improved thickness measurement method for choroidal hyperpermeability in central serous chorioretinopathy.

AIM: To observe choroidal thickness changes in the choroidal hyperpermeability area (CHA) in patients with central serous chorioretinopathy (CSC) after photodynamic therapy (PDT) using indocyanine green angiography (ICGA) combined with optical coherence tomography (OCT). METHODS: This was a cohort study of 17 eyes (17 patients) with CSC. In all patients, the range of CHA was determined by ICGA. The patients were divided into two groups based on CHA covered the fovea (group A) or not (group B). All patients received half-dose verteporfin PDT over CHA in ICGA. Choroidal thickness was measured by OCT before, 1, and 3mo after treatment. The choroidal thickness values of the fovea and CHAs were obtained for each measurement. Secondary outcomes were changes in the best-corrected visual acuity (BCVA) and amount of subretinal fluid (SRF). RESULTS: The differences in center choroidal thickness at baseline and at 1 and 3mo post-PDT were statistically significant in group A and all patients (both P<0.001). There was no significant difference in group B (P=0.059). The differences of thickness of CHA and BCVA at baseline and 1 and 3mo post-PDT were statistically significant in group A, group B, and all patients (all P<0.01). All patients showed complete SRF absorption at 3mo post-PDT. CONCLUSION: Center choroidal thickness does not accurately reflect changes in CHA of patients whose CHA does not covered the fovea center. Using CHA as the observation target can make up for this limitation, expand the scope of application, and reduce bias.

A multiplex PCR for differential detection of Echinococcus granulosus sensu stricto, Echinococcus multilocularis and Echinococcus canadensis in China.

BACKGROUND: Echinococcosis caused by Echinococcus is one of the most major infectious diseases in north-west highland of China. E. granulosus sensu strict, E. multilocularis, and E. canadensis are known to be the only three species related to human health transmitting in the areas. To achieve targeted treatment and control of echinococcosis, the accurate identification and discrimination of the species are important. However, currently the available diagnostic approaches do not present ideal results either in accuracy or efficiency. METHODS: In the study, a set of primers were designed to aim at the three human-pathogenic Echinococcus species in China. The one-step multiplex PCR assay was developed and evaluated for the specificity and sensitivity. A total of 73 parasitic lesions and 41 fecal materials obtained from human and various animals collected in the clinic and the field were tested to assess the applicability of this method. RESULTS: The multiplex PCR effectively detected the individual DNA from the targeted species and their random mixtures generating with distinguishable expected size of products. The detection limit of the assay for each of the three species was 5 pg/µl when they were tested separately. When DNA mixtures of the targeted species containing the same concentration were used as templates, the lowest amount of DNA which can be detected was 50 pg/µl, 10 pg/µl and 5 pg/µl for E. granulosus s. s., E. multilocularis, and E. canadensis respectively. No cross-reactivity was observed when DNA from eight genetically close species was used as control templates. The multiplex PCR identifications of all samples were in line with the original sequencing results except for those infected with E. shiquicus, which showed negative signals in the developed assay. Of all the tested stool materials, 16 were previously found positive for Echinococcus by visual and microscopic examination. Among these 16 samples, 13 were confirmed by the multiplex PCR, and the other three tested negative. Additionally, the multiplex PCR identified another 14 positive feces from the remained 25 stool samples which absence of worms. CONCLUSIONS: The developed multiplex PCR shows advantages in fast diagnosis and large-scale epidemiological investigation, which proven to be a promising tool utilized in clinic and surveillance system.

[A Social Network Perspective on the Transmission of Cysticercuscellulose Infections in Tibetan School Children in Sichuan].

OBJECTIVE: To determine the transmission characteristics of Cysticercuscellulose infections from a social network perspective in Tibetan school children in Sichuan. METHODS: A cluster sampling strategy was adopted to select two primary schools with high level of Cysticercuscellulose infections in the Tibetan agriculture areas of Liangshan prefecture, Sichuan province. All of the students from the selected schools were enrolled in the study. Their social network data, including classroom seating, dormitory roommates, best playmates, and those who shared meals and snacks etc, were collected by trained investigators. Stool and blood samples of the students were collected for parasite detection. The transmission network of Cysticercuscellulose infections and the overall social network of school children were analysed. RESULTS: A total of 644 children participated in the study. Taenia solium were found in 6.11% of the stool samples and 13.25% blood samples returned with seropositive. The transmission was centered around the sources of infections: dormitory-clustering in the boarding school and playmate-clustering in the day school. The overall social network analysis revealed "core people" (more relationships), "information disseminators" (closer to other nodes) and "information hubs" (between two nodes) in both schools. CONCLUSION: Close contacts in dormitories and playgrounds are the main sources of transmission of cysticercosis in the Tibetan schools. The "core people" "information disseminators" and "information hubs" are critical for the prevention and control of cysticercosis in the future.

A mouse model of a novel missense mutation (Gly83Arg) in a Chinese kindred manifesting vitreous amyloidosis only.

The purpose of this study is to establish a mouse model of transthyretin (TTR) Gly83Arg gene mutation by the technique of gene targeting for research on hereditary vitreous amyloidosis (HVA) and to confirm whether this point mutation is a genetic feature of HVA. A vector (pBR322-MK-TTR) was constructed to target ES cells. The successfully transfected ES cells were used for blastocyst injection, thus generating F0. F0 and Flp mice were mated to generate F1 (TTR+/-, Flp +/-) mice that lacked the neo gene but carried the Flp gene. F1 mice were mated with C57BL/6N wild type mice to generate F2 (TTR+/-) mice. F3 homozygous and heterozygous mice were generated by mating F2 mice with each other. PCR and sequencing were performed for F3 mice. Amyloid was detected using Congo red stain and polarized light. Immunohistochemistry was used to detect the expression of TTR in the tissues. Quantitative fluorescent PCR and Western blotting were used to detect the expression of TTR mRNA and TTR protein, respectively. Two F0-generation, 2 F1-generation and 15 F3-generation mice were obtained. The gene sequencing of F3 mice showed TTR Gly83Arg mutation. When examined with Congo red and polarized light, the vitreous of TTR Gly83Arg mutant mice tested positive for amyloid. The hearts, livers, brains and kidneys of the experimental group and control group were all negative by Congo red staining. Immunohistochemical staining showed that the vitreous of TTR Gly83Arg mutant mice and the livers of the control mice were positive, but the kidneys, hearts and brains of both groups were negative. Quantitative fluorescent PCR showed that the mRNA expression of mutant mice was significantly lower than that of wild-type mice (F = 0.295, P = 0.023). Western blotting showed that the expression of TTR protein was significantly lower in the model mice than in the wild-type mice (t = 3.224, P = 0.018). TTR gene mutation is indeed a molecular characteristic of HVA and manifest in the eye disease only. A C57BL/6 mouse line carrying the TTR Gly83Arg gene mutation was successfully established. This strain of mice can be used for the study of HVA.

Protective effect of neovibsanin B on spatial cognitive functions of rats with cerebrovascular hypoperfusion.

Neovibsanins are believed to be promising candidates for the development of novel therapeutic agents to treat neurological diseases like Alzheimer's disease. It has been shown that chronic cerebral hypoperfusion is linked to neurodegenerative disorders and their subsequent cognitive impairment. In the present study effect of neovibsanin B (NVB) on spatial cognitive functions of rats with lobal cerebrovascular hypoperfusion was investigated. The cerebrovascular hypoperfusion rat model was prepared by bilateral common carotid arteries occlusion (2VO). Morris water maze (MWM) test was employed to examine the effect of NVB on spatial cognitive function before and after 2VO intervention. The animals were divided into two groups; long-term memory (LTM) and short-term memory (STM) groups. Each of the groups was subdivided into 3 subgroups: control, untreated and NVB treated groups. After ten weeks of the surgery, all the subgroups were tested with MWM. The results of working memory test for both control and NVB treated groups revealed that escape latency time and total distance travelled were significantly lower compared to untreated group. Similarly, the maze test performance was observed to be significantly improved for control and NVB treated groups. Moreover, the probe memory test performance for control and NVB treated groups was markedly better than untreated group. Thus NVB has a significant effect on the spatial cognitive preservation in rats with chronic cerebral hypoperfusion. Thus NVB can be a promising agent for the spatial cognitive functions improvement.

Transplantation of human cord blood mononuclear cells and umbilical cord-derived mesenchymal stem cells in autism.

BACKGROUND: Autism is a pervasive neurodevelopmental disorder. At present there are no defined mechanisms of pathogenesis and therapy is mostly limited to behavioral interventions. Stem cell transplantation may offer a unique treatment strategy for autism due to immune and neural dysregulation observed in this disease. This non-randomized, open-label, single center phase I/II trial investigated the safety and efficacy of combined transplantation of human cord blood mononuclear cells (CBMNCs) and umbilical cord-derived mesenchymal stem cells (UCMSCs) in treating children with autism. METHODS: 37 subjects diagnosed with autism were enrolled into this study and divided into three groups: CBMNC group (14 subjects, received CBMNC transplantation and rehabilitation therapy), Combination group (9 subjects, received both CBMNC and UCMSC transplantation and rehabilitation therapy), and Control group (14 subjects, received only rehabilitation therapy). Transplantations included four stem cell infusions through intravenous and intrathecal injections once a week. Treatment safety was evaluated with laboratory examinations and clinical assessment of adverse effects. The Childhood Autism Rating Scale (CARS), Clinical Global Impression (CGI) scale and Aberrant Behavior Checklist (ABC) were adopted to assess the therapeutic efficacy at baseline (pre-treatment) and following treatment. RESULTS: There were no significant safety issues related to the treatment and no observed severe adverse effects. Statistically significant differences were shown on CARS, ABC scores and CGI evaluation in the two treatment groups compared to the control at 24 weeks post-treatment (p < 0.05). CONCLUSIONS: Transplantation of CBMNCs demonstrated efficacy compared to the control group; however, the combination of CBMNCs and UCMSCs showed larger therapeutic effects than the CBMNC transplantation alone. There were no safety issues noted during infusion and the whole monitoring period. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01343511, Title "Safety and Efficacy of Stem Cell Therapy in Patients with Autism".

[Assessment of health education against echinococcosis in Tibetan region of Sichuan Province, China].

OBJECTIVE: To find an effective strategy of implementing health education in Tibetan Regions so as to make echinococcosis control sustainable at a large scale. METHODS: During July to November of 2008, surveys were conducted on health education requirements among various populations in the form of questionnaire and group discussion in endemic areas of echinococcosis in three counties of the Ganzi Tibetan Autonomous Prefecture, Sichuan. Based on the obtained results, health education materials suitable for different populations were designed. The materials were applied for conducting health education in field at Tagong Township, Kangding of Ganzi in October, 2009. By the survey in May, 2010, the improved effect on knowledge and behavior change was compared before and after (6 months later) health education in order to assess the usefulness of these materials. Simultaneously, Xinduqiao Township of Kangding was selected as control. This town is neighboring to the study area with similar natural and demographic conditions, in which no health education activities related to the study was implemented. RESULTS: Various populations showed their interested requirements for health education materials and ways. Based on the information collected, a series of materials were designed and applied for health education activities in field. The results indicated that, compared with the data before health education, improvement of the knowledge and behaviors against echinococcosis among students and local residents showed significant increase (P < 0.05), but only one knowledge point about the importance of washing hands before meal among students showed no significant difference (P > 0.05) in spite of the rates increasing from 88.6% (78/88) before health education to 95.5% (84/88) after education. The local officers and monks also showed to some extent improvement on behavior manners. The rate of correct treatment of livestock viscera increased from 37.1% (13/35) and 30.3% (10/33) before the education to 82.9% (29/35) and 78.8% (26/33) (P < 0.01), while the rate of not feeding stray dogs among monks was 6.4% (3/47) before and 10.6% (5/47) (P > 0.05) after the education. The knowledge-increasing and behavior-improving rates on playing dogs among the students, residents and monks increased by 182% and 193%, 42.8% and 54.3%, 6.4% and 14.9%, respectively. There was no considerable change in the control township. CONCLUSION: The materials designed for health education are acceptable by most populations. The improvement rate of knowledge and behaviors is considerable among the groups. Use of the materials receives expected effect on health education and health promotion.

Correlations between serum uric acid level and disease activity, intrathecal inflammation reactivity in patients with multiple sclerosis.

OBJECTIVE: To explore the correlations between serum uric acid (UA) levels and the clinical and cerebrospinal fluid (CSF) parameters of multiple sclerosis (MS). METHODS: The medical reports of 47 MS patients admitted to Peking Union Medical College Hospital during 2008 and 2010 were reviewed. And 49 age- and gender-matched cerebral infarction patients were enrolled as control. The mean serum UA level of the MS patients was compared with that of the control group. The correlations between the UA levels and the clinical parameters including gender, disease duration, relapse rate, and disease disabilities as assessed by the Expanded Disability Status Scale score, were explored. Forty-one patients had CSF examinations. The correlations between the UA levels and the CSF parameters reflecting inflammation and tissue damage, including CSF protein, white blood cell count, oligoclonal band, 24-hour IgG index, and myelin basic protein, were also investigated. RESULTS: The mean serum UA level in the MS patients was lower than that in the control group (247.75±52.59 µmol/L vs. 277.94±74.33 µmol/L, P=0.025) and inversely correlated with the relapse rate (P=0.049). MS patients with lower serum UA levels tended to have higher white blood cell counts and myelin basic protein level. But there was no correlation between CSF protein levels (r=0.165, P=0.273), white blood cell counts (r=-0.051, P=0.732), IgG index (r=0. 045, P=0.802), or myelin basic protein level (r=-0.248, P=0.145) and the serum UA level, respectively. CONCLUSION: In MS patients, UA levels might partly reflect the extent of disability and inflammation.

Epidemiology and risk factor analysis for canine echinococcosis in a Tibetan pastoral area of Sichuan.

OBJECTIVE: To determine the prevalence and evaluate the risk factors of canine echinococcosis based on a field survey of dog infections with Echinococcus granulosus and E. multilocularis in Chalong, Kalong, Dade and Chazha Townships in a district of Ganzi County, Sichuan Province, China. METHOD: Questionnaire associated with the acquisition of canine echinococcosis was administered to dog owners. Stray dogs were examined post-mortem and rectal faeces at necropsy were collected to validate a copro-antigen ELISA. Owned dogs were screened for Echinococcus spp. infection in faeces using the genus specific copro-ELISA and the effectiveness of dog treatment was assessed. Chi-square and one-way ANOVA were used for statistical analysis. RESULTS: The prevalence of Echinococcus spp. infection at necropsy in stray dogs was 60.9% (14/23) in 2000; E. multilocularis infection accounted for 34.8% (8/23) and E. granulosus for 26.1% (6/23). The specificity of the copro-ELISA was 80.0% and the sensitivity was 92.3%, compared with the results at necropsy. Fifty percent of owned dogs (290/580) tested was copro-antigen positive at the beginning of the project in 2000, which decreased to 17% (99/580) in the same cohort of owned dogs after praziquantel treatment (5 mg/ kg) at 6-monthly period from 2003 to 2005. Analysis for risk factors associated with copro-antigen positive dogs showed that the never tethered dogs had a higher rate (40.4%, 65/161) than dogs tethered during the day (32.3%, 109/337), or tethered at night [29.2% (21/72)], or those always tethered [20%(2/10)](P<0.01). Dogs that their owners lacked hydatid transmission knowledge [38.1% (121/318)] and did not have de-worming practice [47.7% (92/193)] had significantly higher copro-antigen positive rate than those dogs that their owners knew relevant knowledge [28.6% (75/262)] and were dewormed regularly [20.4% (79/387)](P<0.05 and P<0.01). There was no correlation between the prevalence and dog sex or age or the varieties of livestock that the owner raised. CONCLUSION: Local dogs show high prevalence with both E. granulosus and E. multilocularis. The copro-ELISA can be used to detect infection of Echinococcus in dogs. Allowing dogs to roam, lack of the basic knowledge of hydatid disease transmission and no de-worming practice for dogs are significant factors for the transmission of canine echinococcosis.

[Biological features of a new Echinococcus species (Echinococcus shiquicus) in the east of Qinghai-Tibet Plateau].

In the eastern Qinghai-Tibet Plateau region, a variety of domestic and wild mammals are involved in the transmission cycles of Echinococcus species. E. granulosus and E. multilocularis are known being sympatrically distributed in the plateau region. Recently, an unknown Echinococcus species was isolated from infected plateau pika (Ochotona curzoniae) and Tibetan fox (Vulpes ferrilata). The species shows quite distinct characteristics on morphology, genetics, host specificity and geographical distribution from others. It was therefore identified as a new Echinococcus species, Echinococcus shiquicus. This paper discussed the biological genetics and epidemiological features of the species, and proposed hypotheses and considerations for further exploration.

The Tibetan hare Lepus oiostolus: a novel intermediate host for Echinococcus multilocularis.

Multicystic hydatids have been found in the livers of hares ( Lepus oiostolus) examined from the Qinghai-Tibet plateau of China. In this study, the causative species was definitively identified as Echinococcus multilocularis by mitochondrial DNA sequencing. This is the first confirmation of larval E. multilocularis from hares. The hydatids contained protoscolices, suggesting that the hare may contribute to the transmission of E. multilocularis on the Tibetan plateau.