[Evaluation effect of COMPERA 2.0 risk assessment model on prognosis of Chinese patients with pulmonary arterial hypertension].

Objectives: To clarify the evaluation effect of COMPERA 2.0 risk assessment model on prognosis of pulmonary arterial hypertension (PAH) in China. Methods: Patients with newly diagnosed PAH admitted in Fuwai hospital between April 2019 and March 2022 were enrolled retrospectively and divided in low, intermediate-low, intermediate-high and high strata by scores of COMPERA 2.0 risk assessment model. All the patients were followed up by clinic or telephone. The primary endpoint was defined as a composite of all-cause mortality, exacerbated heart failure and aggravated symptoms. Kaplan-Meier analysis and log-rank trend test were used to determine the risk of endpoints among the 4 groups. Multivariate Cox proportional hazards regression were used to analyze the association between COMPERA 2.0 scores and prognosis in patients with PAH. Results: A total of 951 patients with PAH were enrolled in this study. The age [M (Q1, Q3)] of the patients was 35 (28, 47) years, of which 706 cases (74.2%) were females. A total of 328 cases (34.5%) were assigned in low strata, 264 cases (27.8%) in intermediate-low strata, 193 cases (20.3%) in intermediate-high strata, and 166 cases (17.5%) in high strata. During the duration [M (Q1, Q3)] of follow-up after discharge of 1.8 (1.0, 2.8) years, the primary endpoint was occurred in 12.8% (42/328), 21.2% (56/264), 28.5% (55/193) and 42.8% (71/166) of low, intermediate-low, intermediate-high and high strata, respectively. The rates of primary endpoint were significantly increased with strata rising (P<0.001). Multivariate Cox proportional hazards regression showed that COMPERA 2.0 risk scores were associated with the primary endpoints in PAH patients (HR=1.801, 95%CI: 1.254-2.588, P=0.001) after adjusting confounders. Conclusion: COMPERA 2.0 risk assessment model is a simple and effective tool for evaluating the prognosis of newly diagnosed PAH patients in China.

[Current trend of breast cancer neoadjuvant treatment in China: a cross-sectional study].

Objective: To investigate the current trend of breast cancer neoadjuvant therapy and provide reference for the improvement of breast cancer clinical guideline in the future. Methods: Questionnaires of cross-sectional survey were sent to 110 hospitals (breast cancer surgery quantity surpassing 200) between July 2018 and September 2018. The stages and subtypes, therapeutic regimen, treatment assession, operation choice and preforming of patients underwent neoadjuvant therapy were recorded. Results: Neoadjuvant treatment has been performed in all of the 110 hospitals. The total number of breast patients underwent neoadjuvant therapy was about 14 550 (17.0% in surgical patients) in 2017. For all of the neoadjuvant patients, the proportion of stageⅡ patients was less than 30% in 81 hospitals, and the proportion of stage Ⅲ was more than 50% in 84 hospitals. The numbers of estrogen receptor (ER) (+ )/human epidermal growth factor receptor-2 (HER-2) (-), ER (-)/HER-2 (+ ) and triple negative subtype breast cancer patients were 3 550 (24.4%), 6 024 (41.4%) and 4 991 (34.3%), respectively. Patient's scruples of relatively delayed operation and weak will of breast conservation after neoadjuvant therapy were the majority reasons for neoadjuvant therapy restriction. Anthracycline followed by taxane was the most usual neoadjuvant therapeutic regimens in 53.6% hospitals, and anthracycline plus taxane was the first choice in 42.7% hospitals. Chemotherapy with targeting therapy was recommended to HER-2 positive neoadjuvant patients in 80.9% hospitals. To assess treatment outcome of neoadjuvant treatment, 42.7% hospitals used MRI in more than 50% patients while the usage rate of MRI was less than 20% in 37.3% hospitals. The proportions of hospital using repeat-marking, tattoo and metal clip as the first method to identify the primary tumor region and lymph nodes were 60.0%, 29.1% and 10.9%, respectively. Breast-conservation rate after neoadjuvant therapy was less than 20% in 87.3% hospitals. Conclusions: Neoadjuvant therapy for breast cancer is widely performed in most hospitals in China, while the proportion of neoadjuvant treatment in patients with operable breast cancer is still low. Meanwhile, the idea of achieving de-escalation operation through neoadjuvant treatment is not promoted and the therapeutic evaluation method of neoadjuvant treatment needs further studies to improve.

[Current trends of breast reconstruction after mastectomy in China: a cross-sectional study].

Objective: To investigate the current trends of breast reconstruction(BR) after mastectomy in China. Methods: A list of hospitals with more than 200 cases of breast cancer surgery per year nationwide was obtained, and 110 institutions were selected according to the geographical distribution. The research was conducted in the form of a questionnaire survey, and 92.3% (169/183) of the questions were single-choice questions. Information such as demographics of surgeons and hospitals, number of mastectomy and BR, type and timing of BR was included in the survey. Survey formal notification letter was issued by the China Anti-Cancer Association Breast Cancer Committee and Chinese College of Surgeons, Committee of Mammary Surgeons. Questionnaires were sent to the respondents of each center by email. The survey time range was from January 1, 2017 to December 31, 2017. All data were completely collected before September 7, 2018. Results: A total of 110 units participated in the survey. In total, 87.3% (96/110) of the hospitals have conducted BR surgery. The BR after mastectomy was 10.7% (6 534/61 099), among this, implant BR accounted for 65.7%(4 296/6 534), autologous BR accounted for 20.1% (1 312/6 534), and autologous combined implant BR accounted for 14.2% (927/6 534). Immediate reconstruction accounted for 67.6% (4 417/6 534) of BR, while delayed BR accounted for 32.4% (2 097/6 534). In 2017, 77.8% (35/45) of the plastic surgery departments cooperated with general surgery departments. General BR could be conducted after mastectomy accounted for 83.6% (92/110). The proportion of reconstruction was positively correlated with the gross domestic product (GDP) per capita (r=0.311, P=0.002). The one-step implant-based BR(IBBR) was the most preferred type in immediate BR. Two-step IBBR was the most preferred method in delayed BR. Hospitals that routinely evaluated aesthetics after BR accounted for 64.6% (62/96), while only 16.7% (16/96) of hospitals used patient-reported outcome measure (PROM). The most commonly used PROM tool was BREAST-Q. Conclusions: The overall BR in China is on upward trend, but gap between China and the developed countries still exists. Breast surgery departments should strengthen further cooperation with plastic surgery departments. Simultaneously, the aesthetics evaluation and PROM after BR should be put a high premium.

[A single-center retrospective study on axillary evaluation in 1 557 breast ductal carcinoma in situ patients between 2006 and 2016].

Objectives: To examine the influence factors on axillary evaluation in ductal carcinoma in situ (DCIS) patients, and the prognosis of different choices of axillary evaluation in a single-center retrospective study. Methods: Totally 1 557 DCIS patients admitted in Department of Breast Surgery, Fudan University Shanghai Cancer Center from January 2006 to November 2016 were retrospectively enrolled. All patients were female. The median age was 49 years (range: 21 to 85 years). Surgical methods included modified radical mastectomy, simple mastectomy (with or without axillary evaluation) and breast conservation surgery (with or without axillary evaluation). Axillary evaluation included axillary lymph node dissection (ALND) and sentinel lymph node biopsy (SLNB). T tests, χ(2) test and Logistic regression analysis was used to analyze influence factors on axillary evaluation, respectively. Kaplan-Meier curve and Log-rank analysis were used to evaluate recurrence-free survival (RFS) and loco-regional recurrence-free survival (LRRFS) in patients with different surgical methods. Results: Among the 1 557 DCIS patients, there were 1 226 cases received axillary evaluation, while 331 cases not received axillary evaluation. Patients were separated into 3 groups by different axillary evaluation choices: SLNB group (957 cases, 61.46%), ALND group (197 cases, 12.65%) and no evaluation group (403 cases, 25.88%). The patients in SLNB group increased significantly (P=0.000), from 3.85% (60/1 557) in 2006 to 75.19% (1 170/1 557) in 2016. The independent influence factors of receiving axillary evaluation were high nuclear grade (OR=3.191, 95%CI: 1.722 to 5.912, P=0.001) and tumor size>15 mm (OR=1.698, 95%CI: 1.120 to 2.573, P=0.012). Also, patients received breast conservation surgery were more likely to refuse axillary evaluation (OR=0.155, 95%CI: 0.103 to 0.233, P=0.000). There were no significant differences in RFS and LRRFS in patients with different axillary evaluation choices. Conclusions: The investigation in trends and influence factors of different axillary evaluation choices provided basis on surgical precision medicine in DCIS patients. Patients received SLNB increased significantly. The independent influence factors of axillary evaluation were nuclear grade, tumor size and surgical methods. There was no significant differences in prognosis among the groups receiving different axillary evaluations.

[Current practice of implant-based breast reconstruction: results from China national practice questionnaire survey].

Objective: To explore the current clinical practice of implant-based breast reconstruction (IBBR) in China. Methods: The current survey was sponsored by Chinese Anti-Cancer Association, Committee of Breast Cancer Society and Chinese Society of Breast Surgeons. A survey was mailed to 110 hospitals in China, which have more than 200 breast cancer operations performed in 2017. The survey mainly included questions on the clinical practice of IBBR, sociodemographic and geographical factors associated with IBBR practice, reasons and concerns for selecting IBBR, type and timing of breast reconstruction, and the complications of IBBR. Data were analyzed using χ(2) test, Fisher's exact test or Kruskal-Wallis rank sum test. Results: IBBR was available in 86.4% (95/110) included hospitals. It was predominantly performed breast reconstruction surgery, the proportion of IBBR in all the breast reconstruction was 65.75% (4 296/6 534). However, the rate of IBBR in all the patients received mastectomy was only 7.06% (4 296/60 877). Among all the included hospitals, the number of implant reconstructions performed in 2017 was 24 (57.5) cases (M(Q(R)), range: 2-565 cases). Factors associated with the performance of IBBR including regional per capita gross domestic product (H=10.47, P=0.005) and annual surgery volume (H=8.30, P=0.016). The main reasons for choosing IBBR were relatively simple surgical procedure, short learning curve and short operation time. The effects of adjuvant radiotherapy on prosthesis, postoperative complications and patient satisfaction were the main concerns for implant reconstruction. Compared with delay reconstruction, a higher proportion of IBBR was observed in immediate reconstruction (83.1% vs. 62.0%, χ(2)=12.522, P=0.000). In all, 10.5% (10/95) hospitals reported more than 10% grade Ⅲ to Ⅳ capsular contracture. The incidence of infections need surgical intervention was reported between 10% and 20% by 4.2% (4/95) hospitals. Hospitals with 6% to 10% implant rupture and 6% to 15% implant removal were 1.1% (1/95) and 4.2% (4/95) respectively. Conclusions: IBBR was the most common used surgery in breast reconstruction after mastectomy. However, the proportion of IBBR in patients after mastectomy was still low. Reginal economy, surgery volume of hospitals, lack of specialty training program and the concern about complications and patient's satisfaction were the factors affecting the development of IBBR.

Thermotolerance, oxidative stress, apoptosis, heat-shock proteins and damages to reproductive cells of insecticide-susceptible and -resistant strains of the diamondback moth Plutella xylostella.

In this study, we investigated thermotolerance, several physiological responses and damage to reproductive cells in chlorpyrifos-resistant (Rc) and -susceptible (Sm) strains of the diamondback moth, Plutella xylostella subjected to heat stress. The chlorpyrifos resistance of these strains was mediated by a modified acetylcholinesterase encoded by an allele, ace1R, of the ace1 gene. Adults of the Rc strain were less heat resistant than those of the Sm strain; they also had lower levels of enzymatic activity against oxidative damage, higher reactive oxygen species contents, weaker upregulation of two heat shock protein (hsp) genes (hsp69s and hsp20), and stronger upregulation of two apoptotic genes (caspase-7 and -9). The damage to sperm and ovary cells was greater in Rc adults than in Sm adults and was temperature sensitive. The lower fitness of the resistant strain, compared with the susceptible strain, is probably due to higher levels of oxidative stress and apoptosis, which also have deleterious effects on several life history traits. The greater injury observed in conditions of heat stress may be due to both the stronger upregulation of caspase genes and weaker upregulation of hsp genes in resistant than in susceptible individuals.

Isolation, identification, and optimal cultivation of a marine bacterium antagonistic to Magnaporthe grisea.

In this paper, a plate confrontation method was used to isolate bacteria antagonistic to the rice blast fungus Magnaporthe grisea from samples collected from China's Dalian Bay. The antagonist strain LM-031 was obtained. We studied this strain's morphological, physiological and biochemical characteristics and analyzed its 16S rDNA sequence. We compared the effects of different culture conditions (type of media, carbon and nitrogen source, incubation temperature and time, and initial pH value) on the inhibitory effect against M. grisea. Strain LM-031 was preliminarily identified as Bacillus pumilus and was found to strongly inhibit M. grisea, especially when grown on BPY medium at an initial pH 7 for 72 h at 30°C. The optimum carbon and nitrogen sources for growth were lactose and peptone, respectively. The most suitable carbon and nitrogen sources for production of active substances were glucose and NH4Cl, respectively. Our results show that development and utilization of B. pumilus LM-031 has great potential for biological control of M. grisea.

[Incidental internal mammary lymph node biopsy in 113 cases of breast cancer undergoingfree abdominal flap breast reconstruction and its influencing factors].

Objective: The aim of the current study is to determine the clinical value of incidental internal mammary lymph node biopsy in free abdominal flap breast reconstruction using internal mammary vessels as recipient vessels and to investigate the risk factors of internal mammary lymph nodes metastasis. Methods: The clinical data of all patients who underwent free abdominal flap breast reconstruction using internal mammary vessels as recipient vessels from November 2006 to December 2015 in the Department of Breast Surgery, Fudan University Shanghai Cancer Center were reviewed in the study. The incidence of internal mammary lymph node biopsy and the rate of metastasis were analyzed. Statistical analysis was conducted to evaluate the risk factors of internal mammary lymph node metastasis. Results: A total of 113 patients met the inclusion criteria, 53 (46.9%) of whom had internal mammary lymph nodes harvested. Four of these were positive for metastatic disease, all in immediate breast reconstructions. The incidence of metastasis was 7.5% in patients who had successful internal mammary lymph node biopsies.The multi-variate Logistic regression analysis showed that invasive tumor size, tumor location and axillary lymph node metastasis were not risk factors for internal mammary lymph node metastasis (P>0.05). Conclusions: Internal mammary lymph nodes found incidentally during recipient vessel exposure may provide important information about internal mammary lymph node metastasis in free flap breast reconstruction. This approach for internal mammary lymph node biopsy reveals an appreciable success rate and is convenient in clinical practice. The size of invasive tumor and the axillary lymph node metastasis are probably associated with internal mammary lymph node positivity.

Analysis of genetic diversity of salt-tolerant alfalfa germplasms.

Random amplified polymorphic DNA technology was used to analyze the genetic diversity of 25 salt-tolerant alfalfa varieties using 30 different primers. Results showed that the percentage of polymorphic loci between single-plant DNA was 81.52%, and that between mixed DNA of various varieties was 61.65%. Compared to the mixed DNA samples, single-plant DNA samples can better reveal the level of genetic variation among and between alfalfa varieties. The gene differentiation coefficients of 18 Chinese salt-tolerant alfalfa varieties and 7 American salt-tolerant alfalfa varieties were 0.271 and 0.152, respectively, showing that the exchange of genes between Chinese salt-tolerant alfalfa germplasms was more frequent than that of American germplasms. As a topical cross-pollinated plant, the genetic structure of biological populations of alfalfa was directly linked to its breeding system. According to the analysis of genetic distance (GD), 25 varieties can be divided into 9 groups, among which, the GD of Tumu No. 1 and Tumu No. 2 was the shortest (0.148), and the GD of Jieda No. 1 and Tumu was the longest (0.786). The analysis of genetic diversity of salt-tolerant alfalfa germplasms provided a theoretical basis for the creation of an alfalfa salt-tolerant core germplasm repository and for the selection and breeding of new salt-tolerant varieties.

Primary presacral adenocarcinoma: a case report and review of the literature.

Primary presacral adenocarcinoma is a rare presacral lesion. We report a 36-year-old male patient with -primary presacral adenocarcinoma. The patient presented with a six-month history of sacrococcygeal pain. MRI demonstrated a 4×3 cm2, well-defined presacral mass. He underwent a parasacrococcygeal procedure with complete resection of the -tumor, which subsequent histology showed adenocarcinoma. At 15 months follow-up, he remains disease free.

Perianal necrotizing fasciitis treated with a loose-seton technique.

AIM: The study evaluated the effect of a loose-seton technique for perianal necrotizing fasciitis. METHOD: The medical records of seven patients with perianal necrotizing fasciitis treated by the loose-seton technique between December 2005 and June 2010 were reviewed. Age, gender, status of diabetes mellitus, duration of symptoms, the length of hospital stay and number of debridements were investigated. RESULTS: Five of the patients were men. The mean age was 53 years and the range was 43-79 years. All seven patients had a past history of acute perianal abscess. Six (85.7%) patients had diabetes mellitus. The mean time for removal of the seton was 24 (14-32) days and the mean hospitalization time was 31 (23-45) days. All patients had primary wound healing. There was no mortality. At a median follow-up 18 (6-60) months one patient required inpatient treatment with cutting-seton for complex anal fistula after 11 months. All patients had normal faecal continence and none of them required a reconstructive procedure during the follow-up. CONCLUSION: The loose-seton technique is an effective treatment for perianal necrotizing fasciitis. The advantages include inhibiting the spread of inflammation, reducing the frequency of debridements, decreasing the area of the wound and limiting extensive scar formation.

Systematic review and meta-analysis of randomized controlled trials comparing stapled haemorrhoidopexy with conventional haemorrhoidectomy.

BACKGROUND: This paper compares stapled haemorrhoidopexy with conventional haemorrhoidectomy for the treatment of haemorrhoids. METHODS: An electronic literature search was undertaken to identify primary studies and systematic reviews. Results on efficacy and safety were analysed. A meta-analysis was conducted to examine long-term outcomes. RESULTS: Twenty-nine randomized clinical trials recruiting 2056 patients were identified. Meta-analysis showed that stapled haemorrhoidopexy was less painful than conventional haemorrhoidectomy. Stapled haemorrhoidopexy required a shorter inpatient stay (weighted mean difference (WMD) -0.95 (95 per cent confidence interval (c.i.) -1.32 to -0.59) days; P < 0.001) and operating time (WMD -11.42 (95 per cent c.i. -18.26 to -4.59) min; P = 0.001). It was also associated with a faster return to normal activities (WMD -11.75 (95 per cent c.i. -21.42 to -2.08) days; P = 0.017). No significant difference was noted between the two techniques in terms of the total incidence of complications. Stapled haemorrhoidopexy was associated with a higher rate of recurrent disease (relative risk 2.29 (95 per cent c.i. 1.57 to 3.33); P < 0.001). CONCLUSION: Stapled haemorrhoidopexy offers some short-term benefits over conventional operation but the total complication rates are similar for both techniques. Stapled haemorrhoidopexy is associated with a higher rate of recurrent disease.

Suppression of telomerase activity and cytokine messenger RNA levels in acute myelogenous leukemia cells in vivo in patients by amifostine and interleukin 4.

High levels of telomerase activity and high rates of cell proliferation are associated with a poor prognosis in acute myelogenous leukemia. Furthermore, cytokine production by leukemia cells is believed to play an important role in determining the proliferative characteristics of leukemia. The in vivo effects of two noncytotoxic agents on these parameters were determined in 33 acute myelogenous leukemia patients. Three daily doses of interleukin (IL) 4 or a single dose of amifostine reduced telomerase activity in the leukemia marrow cells in 7 of 9 and 11 of 13 patients, respectively. The administration of a single dose of amifostine resulted in a reduction in tumor necrosis factor alpha and IL-6 transcript levels in the marrow cells of 10 of 13 and 12 of 13 patients in which these transcripts were present. The administration of only three doses of IL-4 or a single dose of amifostine has a significant effect on leukemia cell parameters, which are believed to have a significant impact on the in vivo biology of the disease and on its response to remission induction therapy.

Versican enhances locomotion of astrocytoma cells and reduces cell adhesion through its G1 domain.

Versican is a large extracellular proteoglycan and is expressed in a variety of tissues including the central nervous system. A malignant astrocytoma cell line U87 with high motility expressed a higher level of versican than another malignant astrocytoma cell line U343 with lower motility. We observed that the U87 cells were less adherent to tissue culture plates than the U343 cells. To investigate the role of versican in astrocytoma cell migration, we generated recombinant products of a mini-versican construct expressed in COS-7 cells. We found that the mini-versican products enhanced astrocytoma cell migration. Furthermore, enhanced migration was promoted by the G1 domain but not the G3 domain of versican. We introduced culture medium containing products of the mini-versican, the G1, and the G3 constructs separately into the astrocytoma cell lines U87 and U343. The mini-versican and the G1 construct, but not the G3 construct, were shown to reduce astrocytoma cell adhesion. The present data suggest that versican exerts its effect on astrocytoma cell migration and adhesion through the G1 domain.

Aggrecan and link protein affect cell adhesion to culture plates and to type II collagen.

Cartilage is a hypocellular tissue in which a balance of matrix molecules, especially aggrecan and link protein, play a critical role in maintaining structural integrity. To study the role of aggrecan and link protein in mediating cell activities, we have stably expressed them in NIH/3T3 fibroblasts and observed the effect on cell-substratum interactions. Overexpression of either protein destabilized the cell-substratum interaction. However, when both were co-expressed, the interaction between cell and substratum was less impaired. Similar results were obtained on type II collagen-coated plates. The addition of exogenous gene products into fibroblast cell lines and chondrocyte culture had the same effect as expression of the genes. The addition of exogenous hyaluronan to the growth medium or treatment of cells with hyaluronidase also decreased cell adhesion, indicating that hyaluronan also plays a role in the cell-substratum adhesion. The presence of aggrecan seems to increase the amount of link protein on the cell surface. Chondrocytes expressing high concentrations of aggrecan and link protein were maintained within a matrix network and were able to survive in suspended culture. Imbalances in aggrecan or link protein concentrations, or degradation of hyaluronan, disrupted the network and caused the chondrocytes to aggregate or adhere to the plates.

[AgNOR of gastational trophoblastic tumors and its clinical significance].

A total of 120 paraffin-embedded gestational trophoblastic tumor tissue blocks was selected and divided into 5 groups: (1) 20 cases of normal chorionic villi. (2) 40 cases of hydatidiform mole with no malignant change during a following-up period of at least two years. (3) 40 cases of hydatidiform mole which developed into invasive mole or choriocarcinoma. (4) 10 cases of invasive mole. (5) 10 cases of choriocarcinoma. Nucleolar organizer regions (NORs) was Ag-stained and AgNOR dots were counted using the Plotion's method. The result showed that there was significant difference between group 1 and group 2 (P < 0.005), group 2 and group 3 (P < 0.001), group 3 and group 4 (P < 0.05). Taking the AgNOR count 4.00 as a standard, 75% of the cases in group 2 (mean = 2.730) was below this standard. The study suggested that with the increase of malignancy of trophoblastic tumor, the AgNOR count increased correspondingly. A quantitative study of AgNOR might be a useful measure to detect the early malignant change of hydatidiform mole.

[Field observation on the relapse pattern in patients naturally infected with vivax malaria from spring to autumn seasons in Cili County, Hunan Province].

215 patients of vivax malaria were treated with chloroquine phosphate alone at the dose of 1.5g for three days from April 1986 to October 1987 in Cili County in the northwest part of Hunan Province. Among them, 58 cases relapsed, the relapse rate being 27.0%. In patients admitted in April and May, as judged from the interval between treatment and the first relapse, the latent period was short, between 60.8d and 63.5d. On the contrary, when chloroquine treatment was given in August and September, the latent period in all the patients was long, between 292.4d and 297.5d. It is very interesting to note that in patients treated in June and July, both long and short latent periods occurred. 72.7% of the patients treated in June had short latent period (63.7d), while 75.0% of the patients treated in July had long latent period (285.4d).

Cloning and expressing of the three repeat fragments of Plasmodium falciparum 11.1 gene.

OBJECTIVE: To clone and express the 3R, 6R and 9R repeat fragments of Plasmodium falciparum(Pf11.1) gene. METHODS: Three repeat fragments from the genomic DNA of Plasmodium falciparum 3D7 strain cultivated were amplified by using the designed primers. The PCR products were cloned into the pT7 vector for bi-direction sequencing. The sequencing results were analysised by GENETYX-MAC. And then the amplified fragments were subcloned into pET32a(+) or pET32b(+) in order to express the recombinant proteins under the induction of IPTG in E. coli BL21. RESULTS: 3R,6R and 9R fragments with sizez of 552 bp, 630 bp and 444 bp respectively were successfully amplified by PCR. The sequence analysis showed that there were 4 more 3AA units and one more 6AA unit in Pf11.1 gene of 3D7 strain as compared with Palo Alto strain. The homologies of the nucleotide sequence between the 3R fragment and the 6R fragment of the two strains were 92.8% and 95.1%, respectively. The amplified 9R fragment contains 139AA repeat units. The three recombinant proteins were expressed in BL21 strain with molecular weights of 45, 60 and 42 kDa. CONCLUSION: We got the 3R, 6R and 9R fragments separately by PCR and expressed them in E. coli successfully. The Pf11.1 gene of 3D7 strain is highly homologous to that of the Palo Alto strain.

[Experimental studies on the incubation period and relapse patterns in vivax malaria in west Hunan].

The paper reports on some biological characteristics of Plasmodium vivax isolated from Cili County of Hunan Province. 27 volunteers inoculated with sporozoites were observed for 1.5 to 2 years. Treatment with chloroquine 1.5g base for 3 days was initiated on the first day of the primary attack and of each relapse. The data indicate that the first latent period in 13 cases developing malaria after short incubation period is very long, being 243.4 (191-297) days; however it is always short, being 55.3 (51-80) days in 14 patients with long incubation period. Definite relationship existing between incubation period and relapse patterns in vivax malaria is thus demonstrated.

[Studies on the variability of incubation period of vivax malaria following mosquito biting].

From September 1985 to May 1987, 30 people were experimentally infected by Anopheles sinensis infected with Plasmodium vivax isolated from northwestern part of Hunan Province. The findings displayed in graphs demonstrate that the incubation period was variably depended on the number of infective mosquitoes used in the experiment. The short incubation period of 15.8 +/- 1.9d was frequently observed in 6 persons bitten by 10 infected mosquitoes. However, when one mosquito was allowed to feed on each of 24 volunteers, the incubation period was either short (17.3 +/- 1.2d) or prolonged (284.7 +/- 37.7d) in the ratio of 1 to 1. Based on these data it is suggested that tertian malaria of long incubation period must exist everywhere in China. In addition, the rational classification of vivax malaria and the ratio between long and short incubation periods in nature are also discussed in detail.