[Study on optimal harvest time of Erigeron breviscapus].

OBJECTIVE: To ascertain the optimal harvest time of Erigeron breviscapus. METHOD: The dry matter weight accumulation of different organs in growth process and contents of scutellarin and coffeic acid ester in whole plant of E. breviscapus were determined. RESULT: The number of leaves per plant, the dried weight of single leaf and dry matter weight of whole plant and different organs reached the highest after seedling 130-140 d. The content of scutellarin gradually decreased with growth period, and sharply decreased after seedling 140 d. The content of coffeic acid ester varied irregularly with growth period. CONCLUSION: The optimal harvest time of E. breviscapus is in early bloom period after seedling 130 d.

[Sequencing of SLC26A4 exons 7 and 8 and hot spot mutation analysis in 1552 moderate to profound sensorineural hearing loss patients in China].

OBJECTIVE: To investigate the hot spot mutation of SLC26A4 gene and its incidence among patients with moderate to profound sensorineural hearing loss (SNHL) and to analyze the epidemiology of enlarged vestibular aqueduct syndrome in China. METHODS: Peripheral blood samples were collected from 1,552 students of deaf and dumb school in 21 cities throughout China. The nationality distribution of the 1,552 students included Han (n = 1290), Uigur (n = 69), Hui (n = 37), Mongolian (n = 31), and Southwest minorities including Yi, Zhuang, Bai, Miao and other 14 nationalities (n = 125). The hot spot mutation IVS7-2A > G and other mutations in the SLC26A4 exons 7 and 8 with intron 7 were analyzed by direct sequencing. RESULTS: Mutation in the SLC26A4 exons 7 and 8 or intron 7 were found in 199 students, of whom 83 carried IVS7-2A > G homozygous mutation, 114 carried IVS7-2A > G heterozygous mutation, and the other two carried two other kinds of mutation. Of the 1,552 cases, the percentage of cases carrying IVS7-2A > G mutation was 12.7% (197/1,552), and this percentage reached up to 14.3% in 1,290 cases of Han nationality, while in the 69 cases of Uigur nationality this ratio was 0. The prevalence rates of IVS7-2A > G mutation in Zhuozhou and Gaobeidian, Hebei province, and Anyang, Henan province, were 24.7% and 28.3% respectively, both significantly higher than the percentages of the whole China and other regions (all P < 0.05). CONCLUSION: Hereditary SNHL caused by SLC26A4 mutations accounts for a high percentage in China. It is of great importance to screen SLC26A4 gene for making etiological diagnosis for deafness. Screening of the hot spot mutation of IVS7-2A > G is of advantage for large scale screening among patients with deafness.

Nonsense mutations in the PAX3 gene cause Waardenburg syndrome type I in two Chinese patients.

BACKGROUND: Waardenburg syndrome type I (WS1) is an autosomal dominant disorder characterized by sensorineural hearing loss, pigmental abnormalities of the eye, hair and skin, and dystopia canthorum. The gene mainly responsible for WS1 is PAX3 which is involved in melanocytic development and survival. Mutations of PAX3 have been reported in familiar or sporadic patients with WS1 in several populations of the world except Chinese. In order to explore the genetic background of Chinese WS1 patients, a mutation screening of PAX3 gene was carried out in four WS1 pedigrees. METHODS: A questionnaire survey and comprehensive clinical examination were conducted in four Chinese pedigrees of WS1. Genomic DNA from each patient and their family members was extracted and exons of PAX3 were amplified by PCR. PCR fragments were ethanol-purified and sequenced in both directions on an ABI_Prism 3100 DNA sequencer with the BigDye Terminator Cycle Sequencing Ready Reaction Kit. The sequences were obtained and aligned to the wild type sequence of PAX3 with the GeneTool program. RESULTS: Two nonsense PAX3 mutations have been found in the study population. One is heterozygous for a novel nonsense mutation S209X. The other is heterozygous for a previously reported mutation in European population R223X. Both mutations create stop codons leading to truncation of the PAX3 protein. CONCLUSIONS: This is the first demonstration of PAX3 mutations in Chinese WS1 patients and one of the few examples of an identical mutation of PAX3 occurred in different populations.

[Patients suffered from enlarged vestibular aqueduct syndrome in Chifeng deaf and dumb school detected by Pendred's syndrome gene hot spot mutation screening].

OBJECTIVE: To investigate the incidence of hot spot mutation of PDS gene by genetic screening testing method in Chifeng City, Inner Mongolia. The feasibility and effectiveness of genetic screening method in finding enlarged vestibular aqueduct syndrome were confirmed by temporal bone CT scan. METHODS: DNA were extracted from peripheral blood of 141 students of Chifeng Deaf and Dumb school. PDS IVS7-2 A-G mutation, the most common PDS mutation in Chinese population, was analyzed by direct sequencing for PDS exon 7, exon 8 with intron 7. The individuals found with homozygous or heterozygous PDS IVS7-2 A-G mutation were given further temporal CT scan, ultrasound scan of thyroid and thyroid hormone assays. The results of PDS genetic screening and temporal bone CT scan were compared with each other. RESULTS: The sequencing results revealed twenty cases carrying PDS IVS7-2 A-G mutation, of whom nine cases were homozygous mutation and eleven cases were heterozygous mutation. Eighteen cases underwent temporal bone CT scan except two cases that left the school due to other health problem. Sixteen cases were confirmed to be enlarged vestibular aqueduct syndrome (EVAS) by CT scan and the shape and function of thyroid were clinically normal by ultrasound scan of thyroid and thyroid hormone assays, respectively. CONCLUSIONS: The patients suffered from EVAS can be diagnosed by the screening for the PDS hot spot mutation which has unique advantage in epidemiologic study in large scale deaf population. The preliminary data of this study suggested relatively high incidence of EVAS in Chifeng area.

[Clinical analysis of curative effect of rhG-CSF on chemotherapy-induced leukopenia in cancer patients].

Myelosupression is the major dose-limiting toxicity in most chemotherapeutic drugs. To evaluate the curative effect of a domestic product of rhG-CSF on chemotherapy-induced leukopenia, 132 patients with malignancies were enrolled, including 80 patients with lung cancer, 35 patients with breast cancer, 10 patients with nasopharyngeal carcinoma, 3 patients with non-Hodgkin's lymphoma, 2 patients with gastric carcinoma and 2 patients with bone metastasis. Total of 528 cycles of chemotherapy were performed. The results showed that according the grade of leukopenia, the different daily doses of the domestic product of rhG-CSF were administered: 75 micro g/d for 3 days, 150 micro g/d for 4 days and 300 micro g/d for 5 days, in grade I-II, grade III and grade IV groups, respectively, the times of recovery to normal level of white blood cells were 2.5, 4.2 and 7 days in 3 groups, respectively. In conclusion, The Chinese product of rhG-CSF shortened the duration of leukopenia and accelerated the hematologic recovery, which shows only slight side effects, so that patients receive the optimal doses of chemotherapy and completed the planned schedule on time.