[Research advances of collagen-based biomaterials in wound repair]

Acute or chronic wounds are common clinical problems. Collagen, with advantages including rich sources, impeccable biocompatibility, and inherent biodegradability, has been widely used in fundamental research and clinical treatment of wound repair with broad prospects of clinical applications. This article provided a brief overview of the role of collagen in various biological processes related to wound healing and also outlined the sources of collagen. Furthermore, the article summarized the application and recent research advancements of collagen-based wound dressings in the field of wound repair.

Assisted reproductive technology service availability, efficacy and safety in mainland China: 2016

STUDY QUESTION

What is the current status of assisted reproductive technology (ART) service availability, efficacy and safety in mainland China?

SUMMARY ANSWER

In this first national report on ART status in mainland China, data on treatment numbers, outcomes and complications in 2016 are provided and analyzed, respectively.

WHAT IS KNOWN ALREADY

National ART Service Provision Surveys are conducted in mainland China regularly. Data were analyzed, and this manuscript was written by team members from the National Center for Women and Children's Health, China CDC and the Department of Women and Children Health, National Health Commission of the People's Republic of China.

STUDY DESIGN, SIZE AND DURATION

A cross-sectional nationwide survey was completed in 2018, in which data regarding ART treatments, performed from 1st January to 31st December2016 in 445 ART clinics located in 31 provinces of mainland China, were collected.

PARTICIPANTS/MATERIALS, SETTING AND METHODS

There were in total 451 licensed ART clinics (including artificial insemination clinics) in mainland China in 2016, of which 445 submitted service data. A total of 906 840 cycles were provided by 323 in vitro fertilization (IVF) clinics, involving 375 770 conventional IVF cycles, 154 948 intracytoplasmic sperm injection (ICSI) cycles, 367 146 frozen embryo transfer (FET) thawing cycles and 8976 preimplantation genetic diagnosis (PGD) treatment cycles. A total of 161 376 artificial (i.e. intrauterine) insemination (AI) cycles were reported by 443 clinics, with 126 872 cycles using the husband's semen (AIH) and 34 504 using donor semen (AID).

MAIN RESULTS AND THE ROLE OF CHANCE

In total, 98.7% of the licensed clinics, contributing to 100% of the ART services (including AID and AIH cycles), were included in this report. (Six clinics provided institutional information only and were excluded.) There were 906 840 in vitro fertilization cycles performed in mainland China with a population of over 1.3 billion inhabitants, with cycles per million inhabitants (C/M) increasing from 360 in 2013 to 657 in 2016, nationwide (range among provinces: 45-3676). After treatment with conventional IVF, the clinical pregnancy rate (PR) per oocyte retrieval cycle was 23.2%, the delivery rate (DR) per oocyte retrieval cycle was 18.7% and the proportion of twin delivery among the total deliveries was 27.9%. For ICSI cycles, the PR, DR and TDR were 20.5%, 16.7% and 27.2%, respectively. For FET per thawing cycles, the PR, DR and TDR were 48.2%, 37.6% and 24.2%. For PGD per diagnosis cycles, the PR, DR and TDR were 38.1%, 29.7% and 4.2%. For AIH cycles, the PR and DR were 13.3% and 10.5%; for AID cycles, the PR and DR were 24.3% and 21.1%, respectively. The total number of live infants born in mainland China in 2016, was 18.46 million, and the number of infants born through ART conducted in 2016 was 311 309, which accounted for 1.69% of the total. The reported rate of birth defects was about 87/10 000. The incidence of moderate to severe ovarian hyper-stimulation syndrome (OHSS) was 11.5 per 1000 oocyte retrieval cycles, and other complications were much more rare.

LIMITATIONS AND REASONS FOR CAUTION

This report is based on the summary data of ART services provided. The success rates were not calculated by age stratification. A low rate of birth defects was reported, which might be confounded by variations in birth follow-up methods, statistical timing and record taking.

WIDER IMPLICATIONS OF THE FINDINGS

ART service availability has improved significantly in recent years in mainland China. Because China is a vast country, significant imbalances in ART service provision do exist; however, the main efficacy and safety indicators were close to those of western countries.

TRIAL REGISTRATION NUMBER

N/A.

STUDY FUNDING/COMPETING INTEREST(S)

The study was funded by the National Key R&D Program of China (2016YFC1000307-2). There are no competing interests.

[Current situation of initial female fertility evaluation in assisted reproductive institutions in China in 2019]

The evaluation of female fertility at first diagnosis is an important premise and basis for determining the treatment scheme of assisted reproduction. In this study, a survey was conducted among 13 assisted reproductive institutions in China to understand the evaluation indicators and detection methods of female fertility at first diagnosis in various institutions, and provide a basis for reasonable selection of indicators. The survey showed that the indicators of female fertility evaluation at first diagnosis among assisted reproductive institutions included general health indicators, ovarian reserve indicators, and uterine conditions, etc. The selection of indicators was considerably consistent, but the detection methods were quite different. Therefore, it is necessary to choose the detection method with better validity and less harm.

miR-147b-modulated expression of vestigial regulates wing development in the bird cherry-oat aphid Rhopalosiphum padi.. [DOI: 10.21203/rs.2.9668/v3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Background: Most aphids exhibit wing polyphenism in which wingless and winged morphs produce depending on the population density and host plant quality. Although the influence of environmental factors on wing polyphenism of aphids have been extensively investigated, molecular mechanisms underlining morph differentiation (i.e. wing development /degeneration), one downstream aspect of the wing polyphenism, has been poorly understood. Results: We examined the expression levels of the twenty genes involved in wing development network, and only vestigial (vg) showed significantly different expression levels in both whole-body and wall-body of third instar nymphs, with 5.4- and 16.14- fold higher expression in winged lines compared to wingless lines, respectively in Rhopalosiphum padi. vg expression was higher in winged lines compared to wingless lines in third, fourth instar nymphs and adults. Larger difference expression was observed in third (21.38-fold) and fourth (20.91-fold) instar nymphs relative to adults (3.12-fold). Suppression of vg using RNAi repressed the wing development of third winged morphs. Furthermore, dual luciferase reporter assay revealed that the miR-147 can target the vg mRNA. Modulation of miR-147b levels by microinjection of its agomir (mimic) decreased vg expression levels and repressed wing development. Conclusions: Our findings suggest that vg is essential for wing development in R. padi and that miR-147b modulates its expression.

Vestigial mediated by miR-147b regulates wing development in the bird cherry-oat Rhopalosiphum padi.. [DOI: 10.21203/rs.2.9668/v2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Background: The wing polyphenism occurs under crowding and nutrition-deficiency conditions in most aphid species. Although the influence of environmental factors on wing polyphenism of aphids have been extensively investigated, molecular mechanisms underlining morph differentiation (i.e. wing development /degeneration) has been poorly understood. Results: We examined the expression levels of the twenty genes involved in wing patterning network, and only vestigial (vg ) showed significantly different expression levels in both whole-body and wall-body of third instar nymphs, with 5.4- and 16.14- fold higher in winged lines compared to wingless lines, respectively in Rhopalosiphum padi . Moreover, vg expressions were higher in winged aphids compared to wingless aphids at third, fourth instar nymphs and adults, and larger difference ratio were observed in third (21.38-fold) and fourth (20.91-fold) instar nymphs relative to adult (3.12-fold) between wing morphs. Suppression of vg using RNAi repressed the wing development of third winged morphs. Furthermore, dual luciferase reporter assay revealed that the miR-147 can target the vg mRNA, and modulation of miR-147b levels by microinjection of its mimics decreased vg expression levels and repressed wing development. Conclusions: Our findings suggest that vg is essential for wing development and that miR-147b modulates its expression. To our knowledge, our results provide an evidence that miRNA is involved in the regulation of wing morphs in aphids.

miR-147b-modulated expression of vestigial regulates wing-morph differentiation in the bird cherry-oat aphid Rhopalosiphum padi.. [DOI: 10.21203/rs.2.9668/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Background The wing polyphenism occurs under crowding and nutrition-deficiency conditions in most aphid species. Although the influence of environmental factors on wing polyphenism of aphids have been extensively investigated, molecular mechanisms underlining wing-morph differentiation has not been fully understood. Results The expression levels of the twenty genes involved in wing patterning network were examined, and only vestigial (vg) showed significantly different expression levels in both whole-body and wall-body of third nymphal instars, with 5.4- and 16.14- fold higher in winged lines compared to wingless lines, respectively in Rhopalosiphum padi. Moreover, vg expressions were higher in winged aphids compared to that in wingless aphids of third, fourth instar nymphs and adults, and larger difference ratio were observed in third (21.38-fold) and fourth (20.91-fold) instar nymphs relative to adult (3.12-fold) between wing morphs. Suppression of vg using RNAi repressed the wing development of third winged morphs. Furthermore, modulation of miR-147b levels by microinjection of its mimics decreased vg expression levels and repressed wing development. Conclusions Our findings suggest that vg is essential for wing development and that miR-147b modulates its expression. To our knowledge, our results provide an empirical evidence that miRNA is involved in the regulation of wing morphs in aphids.

Association of ectomycorrhizal fungi with Picea crassifolia (Pinaceae, Piceoidae) from high-altitude stands in Mount Helan Nature Reserve, China

We investigated the diversity of ectomycorrhiza associated with the endemic Picea crassifolia in Mount Helan National Nature Reserve in Inner Mongolia, China. Toward this objective, we conducted morphological and molecular identification of ectomycorrhizae in soil cubes taken from pure P. crassifolia stands. Eleven types of ectomycorrhizal (ECM) organisms were separated, briefly described, and identified. Nine morphotypes belonged to the phylum Basidiomycotina [Amphinema byssoides, Cortinarius sp (cf. limonius), Cortinarius vernus, Inocybe cf. nitidiscula, Inocybe sp 1, Sebacina incrustans, Sebacina sp, Suillus luteus, and Piceirhiza tuberculata x Picea crassifolia (comb. Nov.)], and two morphotypes to the phylum Ascomycotina (Cenococcum geophilum and Helvella sp). The diversity of ECM organisms in P. crassifolia was lower than that reported by other studies on spruce or pine forests, or on sporocarp diversity in the high-mountain forests of China. Most of the fungi in the rhizosphere did not correspond to species previously recorded as sporocarps above ground. Here, several new ectomycorrhiza morphotypes are proposed and described. We also confirmed the ectomycorrhizal status of the genus Sebacina (order Sebacinales).

The clinical significance of CA19-9 in ovarian mature cystic teratoma

OBJECTIVE

To evaluate the clinical significance of CA19-9 in patients with ovarian mature cystic teratoma (MCT).

MATERIALS AND METHODS

A retrospective study was performed on 65 patients with pathologically-confirmed MCT and 80 patients with benign epithelial ovarian tumors. Serum tumor markers for all patients and tissue CA19-9 for MCTs were measured. The relationships between clinical characteris- tics of MCTs and CA19-9, as well as the correlation between serum and tissue level of CA19-9 in MCTs, were evaluated.

RESULTS

The mean serum level of CA19-9 in MCTs was significantly higher than that in benign ovarian epithelial tumors (49.9 ± 73.4 IU/ml vs. 17.08 ± 24.8 IU/ml). CA19-9 was the only tumor marker with a mean serum level above the cut-off value and the elevation rate was 30.76% in MCTs. The positive tissue expression rate of CA19-9 in MCT patients were 50.9% and were higher than that of preoperative serum levels (50.9% vs. 32.7%).

CONCLUSION

Serum CA19-9 has the highest positivity rate among other tumor markers in MCT. Elevated serum CA19-9 is not an uncommon finding MCT and could be used as a marker in the differential diagnosis of MCT in patients with pelvic mass.

Enhanced effect of β-tricalcium phosphate phase on neovascularization of porous calcium phosphate ceramics: in vitro and in vivo evidence

Neovascularization plays a key role in bone repair and regeneration. In the present study, four types of porous calcium phosphate (CaP) ceramics, namely hydroxyapatite (HA), biphasic calcium phosphates (BCP-1 and BCP-2) and β-tricalcium phosphate (β-TCP), with HA to β-TCP ratios of 100/0, 70/30, 30/70 and 2/98, respectively, were investigated in terms of their angiogenic induction. The in vitro cell culture revealed that the ceramics could promote proliferation and angiogenesis of human umbilical vein endothelial cells (HUVECs). This result could be achieved by stimulating CCD-18Co human fibroblasts to secrete angiogenic factors (vascular endothelial growth factor, basic fibroblast growth factor and transforming growth factor-β) as a paracrine effect, as well as by up-regulating HUVECs to express these angiogenic factors and their receptors (KDR, FGFR1 and ACVRL1) and the downstream eNOS as an autocrine effect. These effects were more significant in β-TCP and BCP-2, which had a higher content of β-TCP phase. In the in vivo implantation into the thigh muscles of mice, the process of neovascularization of the ceramics was initiated at 2 weeks and the mature vascular networks were formed at 4 weeks as visualized by hematoxylin and eosin staining and scanning electron microscopy. Microvessel density count confirmed that β-TCP and BCP-2 induced more microvessels to form than HA or BCP-1. This phenomenon was further confirmed by the significantly up-regulated expressions of angiogenesis-related genes in the ingrowth of cells into the inner pores of the two ceramics. All the results confirmed the angiogenic induction of porous CaP ceramics, and a higher content of β-TCP phase had an enhanced effect on the neovascularization of the ceramics.

Enhanced repair of a critical-sized segmental bone defect in rabbit femur by surface microstructured porous titanium

Repair of load-bearing bone defects remains a challenge in the field of orthopaedic surgery. In the current study, a surface microstructured porous titanium (STPT) successively treated with H2O2/TaCl5 solution and simulated body fluid was used to repair the critical-sized segmental bone defects in rabbit femur, and non-treated porous titanium (NTPT) and porous biphasic calcium phosphate ceramics (PBCP) were used as control, respectively. A 15 mm long implant was positioned in the femoral defect and stabilized by a plate and screws fixation. After implantation into the body for 1, 3 and 6 months, X-ray observation confirmed that porous titanium groups (NTPT and STPT) provided better mechanical support than PBCP group at the early stage. However, there was no obvious difference in the formed bony callus between PBCP and STPT groups in the later stage, and they both showed better shape of bony callus than NTPT group. Micro-CT and histomorphometric analysis for the samples of 6-month implantation demonstrated that more new bone formed in the inner pores of PBCP and STPT groups than that in NTPT group. Moreover, the biomechanical tests revealed that STPT group could bear larger compressive load than NTPT and PBCP groups, almost reaching the level of the normal rabbit femur. STPT exhibited the enhanced repairing effect on the critical-sized segmental bone defect in rabbit femur, meaning that it could be an ideal material for the repair of large bone defect in load-bearing site.

The enhanced effect of surface microstructured porous titanium on adhesion and osteoblastic differentiation of mesenchymal stem cells

Porous titanium with appropriate surface treatments can be osteoinductive. To investigate the effect of surface treatments of porous titanium on the attachment and differentiation of mesenchymal stem cells (MSCs), two kinds of surface microstructured porous titaniums, H₂O₂/TaCl₅ treated one (HTPT), and H₂O₂/TaCl₅ and subsequent simulated body fluid (SBF) treated one (STPT) were fabricated, and non-treated one (NTPT) was used as control. The morphology, specific surface area (SSA), pore distribution and mechanical strength of these materials were characterized respectively, and the results showed that H₂O₂/TaCl₅ treatment led to a significant increase in both SSA and micropores of HTPT, and the further SBF immersion resulted in the formation of a layer of bone-like apatite on the surface of STPT. Although the surface treatments had a little negative impact on the compressive strength and elasticity modulus of porous titanium, the mechanical strength of HTPT or STPT was enough for the bone defect repair of the load-bearing sites. The protein adsorption and cell adhesion experiments confirmed that the microstructured surface notably enhanced porous titanium's protein binding capacity and promoted MSCs adhesion on the surface. More importantly, cell differentiation experiments proved that the microstructured surface evidently elevated the osteoblastic gene expressions of MSCs compared to NTPT. The enhanced biological effect by the surface treatments was more robust on STPT. Therefore, our results suggest that the microstructured surface has great potential for promoting MSCs differentiation towards osteoblasts, giving excellent support for the osteoinduction of porous titanium with appropriate surface treatments.

First Report of Rice stripe virus in Vietnam

Rice stripe virus (RSV) is the type member of the genus Tenuivirus, and one of the prevalent viruses infecting rice. The disease was first recorded in central Japan in 1903, and is currently present in many Asian countries, including South Korea and China in the Far East (1,2). In May of 2012, a disease outbreak in Indica rice (Oryza satira L.) caused losses in a field in Huaifu, Hungyen, Vietnam (20°53'N, 106°02'E). Infected plants showed yellowing stripe symptoms on leaves. A survey indicated that disease incidence was about 10%. Six leaf samples were randomly collected and four were found positive in dot-ELISA using RSV-specific monoclonal antibodies (provided by Dr. X. Zhou, Institute of Biotechnology, Zhejiang University) (3). To confirm RSV infection, total RNA was extracted from dot-ELISA positive and asymptomatic control samples. RT-PCR was performed using RSV-specific primers (CP(+): 5'-GAGGATCCATGGGTACCAACAAGCCAG-3', CP(-): 5'-TCGTCGACCTAGTCATCTGCACCTTCTG-3'; SP(+): 5'-TGGGATCCATGCAAGACGTACAAAGGAC-3', SP(-): 5'-CTGTCGACCTATGTTTTATGAAGAAGAGGT-3'; NS2(+): 5'-GAGGATCCATGGGTACCAACAAGCCAG-3', NS2(-): 5'-CCGTCGACTCATACATCTGAATTTG-3'; NS3(+): 5'-ACCGGATCCATGACTATCAAATACAAC-3', NS3(-): 5'-CCGTCGACTCATACATTAGCTATTGTC-3') that amplify the coat protein, disease-specific protein, and NS2 and NS3 genes of RSV, respectively. Amplicons of the expected size were obtained from the four symptomatic but not the asymptomatic plants. Amplicons obtained from one of the positive samples were cloned into the vector pMD18-T (TaKaRa, Dalian, China) and sequenced (GenBank Accession Nos. KC197055 to KC197058). Sequence comparisons indicated that the complete sequences of the CP, SP, NS2, and NS3 of the Vietnamese isolate shared 97.1%, 97.5%, 96.8%, and 97.3% sequence identity at the nucleotide level with the corresponding genes of RSV isolate T (NC_003776, NC_003753, and NC_003754, respectively). These results indicate that the virus associated with yellowing stripe disease of rice in Vietnam is an isolate of RSV. To our knowledge, this is the first report of RSV in Vietnam. This finding redefined the distribution of RSV in the world. Research on whole-genome sequencing of the Vietnamese isolate is continuing and is being expanded to compare the genetic diversity of the virus, assisting in the study of the evolution of the virus. References: (1) S. Toriyama. Microbiol. Sci. 3:347, 1986. (2) Q. Y. Lin et al. J. Fujian. Agric. Univ. 20:24, 1991. (3) G. Z. Wang et al. Acta Phytopathol. Sinica 34:302, 2004.

Three dimensional microfluidics with embedded microball lenses for parallel and high throughput multicolor fluorescence detection

We report a 3D microfluidic device with 32 detection channels and 64 sheath flow channels and embedded microball lens array for high throughput multicolor fluorescence detection. A throughput of 358 400 cells/s has been accomplished. This device is realized by utilizing solid immersion micro ball lens arrays for high sensitivity and parallel fluorescence detection. High refractive index micro ball lenses (n = 2.1) are embedded underneath PDMS channels close to cell detection zones in channels. This design permits patterning high N.A. micro ball lenses in a compact fashion for parallel fluorescence detection on a small footprint device. This device also utilizes 3D microfluidic fabrication to address fluid routing issues in two-dimensional parallel sheath focusing and allows simultaneous pumping of 32 sample channels and 64 sheath flow channels with only two inlets.

Chondrogenic differentiation of mesenchymal stem cells induced by collagen-based hydrogel: an in vivo study

Chondrogenic differentiation of mesenchymal stem cells (MSCs) relies on inductive media of chondrogenic environment. With proper design, a cellular microenvironment mimicking chondrogenic environment might be created to induce chondrogenesis of MSCs. In this study, bone marrow mesenchymal cells (BMSCs) were encapsulated in collagen-based hydrogel, and then enclosed in diffusion-chambers which allow the body fluid to permeate and preclude the host cells to invade. Then, the chamber with the hydrogel-BMSCs composite was implanted in the back of rabbits subcutaneously. The specimens in the chamber were harvested for histological, immunohistochemical, and RT-PCR analyses after 8 weeks. The results showed that cells with the characteristic of chondrocytes were homogenously distributed and the extracellular matrix (ECM) of cartilage has been secreted, indicating the chondrogenic differentiation of BMSCs. As control, nothing was obtained with only BMSCs. Moreover, the expression of collagen type II, indicator of cartilage ECM, was less in tissues with collagen-alginate-hydrogel (CAH) than that with collagen-hydrogel (CH). The results showed that both CH and CAH may induce the chondrogenesis and the induction is materials dependent. From in vitro experiments, TGF-beta is a necessary signal molecule for chondrogenesis, and it was suggested that the material may take in vivo growth factors to trigger chondrogenesis. From the studies, the chondrogenic induction of the hydrogel may be ascribed to that the hydrogel may provide a suitable environment and aggregate the signal molecule for chondrogenesis in vivo. The results would lend valuable reference in clinical for selection of appropriate scaffold for cartilage repair.

Induction of a germline mutation at a hypervariable mouse minisatellite locus by 252Cf radiation

Male C3H/HeN mice were exposed to 252Cf radiation and mated with unirradiated C57BL/6N females. F1 mice were analyzed for germline mutation at the paternally derived C3H/HeN allele of a hypervariable minisatellite locus, Ms6hm. This locus exhibited a high frequency of length change mutation spontaneously, and the mutation frequency of the paternally derived C3H/He allele in F1 mice born to unirradiated males was 8.4%. Exposure of male mice to 252Cf radiation resulted in even higher frequency of germline mutation. The spermatid stage germ cells were most sensitive to neutrons, and the mutation frequencies of the paternal allele were elevated to 18%, 26% and 24% for 0.35, 0.7 and 1.02 Gy of 252Cf radiation, respectively. Spermatozoa and spermatogonia stages were less sensitive and the mutation frequencies for 1.02 Gy of 252Cf radiation were 16% and 19%, respectively. The 252Cf radiation consisted of 35% gamma-rays and 65% neutrons. Assuming that these two radiations act additively, RBE of 252Cf neutrons for the induction of minisatellite mutation was calculated to be 5.9 for spermatozoa stage irradiation, 2.6 for spermatid stage irradiation and 6.5 for spermatogonia irradiation.

Association of minisatellite instability with c-myc amplification and K-ras mutation in methylcholanthrene-induced mouse sarcomas

Instability of microsatellite sequences are frequently found in human tumors. In addition, minisatellite sequences, another group of highly unstable sequences, serve as sensitive markers of genetic instability. We have studied minisatellite instability in methylcholanthrene-induced mouse sarcomas. These sarcomas frequently carry the amplified c-myc gene. Seven sarcomas without the amplification and seven others with the amplification were selected randomly. Regardless of the state of the c-myc gene amplification, these sarcomas exhibited a varying degree of transplantability in syngeneic mice. The hypervariable mouse minisatellite locus Ms6hm was found to be highly unstable, specifically among sarcomas with the amplified c-myc gene. However, chromosome instability, as analyzed by micronucleus assay, was observed similarly for two groups of sarcomas. In addition, transversion of G to C and A to T was detected at the K-ras gene in four of the seven sarcomas with the amplified c-myc gene, and these mutations are thought to be induced directly by methylcholanthrene. Thus, concomitant occurrence was observed for three seemingly unrelated mutations, amplification of the c-myc locus, point mutation of the K-ras gene, and instability at the hypervariable mouse minisatellite locus. The present study indicates a possible involvement of K-ras mutation and c-myc amplification in induction of genetic instability in methylcholanthrene-induced mouse sarcomas.

Dose-response of a radiation induction of a germline mutation at a hypervariable mouse minisatellite locus

Dose-response of an induction of a germline mutation was studied at a hypervariable mouse minisatellite locus, Ms6hm, which consists of tandem repeats of a sequence motif GGGCA. Male C3H/HeN mice were exposed to various doses of 60Co gamma-ray and mated with unirradiated C57BL/6N female mice. Matings were done at various time after irradiation to assess the effects of radiation on spermatozoa, spermatids and spermatogonia. DNA samples of F1 offsprings were analysed by Southern blotting for the repeat length mutation at the Ms6hm locus. The mutation frequency per gamete of the paternal allele was 9.1% for the unirradiated control group. The spermatids stage was most sensitive to radiation and a statistically significant dose-response was observed. The mutation frequency of the paternal allele in F1 mice increased to 22% for 1 Gy, 28% for 2 Gy, and 28% for 3 Gy. The spermatogonia stage was less sensitive to radiation, and the mutation frequencies of the paternal allele were 14% for 2 Gy, and 16% for 3 Gy. The spermatozoa stage germ cells were also less sensitive and the frequency of mutation of the paternal allele increased to 14% for 3 Gy. However, these increases were statistically not significant. Possible mechanisms of radiation induction of germline mutation at the hypervariable minisatellite locus will be discussed.

[Clinical and experimental study of tablet cucumber vine compound in treating essential hypertension]

389 patients with essential hypertension were divided into two groups randomly. 241 patients were treated by tablet of cucumber vine compound and 148 patients by tablet of hypotension compound as control. The symptomatic marked improvement and total effective rate were 63.1% and 81.7% in the treated group and 39.2% and 67.0% (P less than 0.01) in the control group respectively. The marked effective rate in decrease of blood pressure and total effective rate were 52.7%, 90.9% and 58.1%, 92.6% (P greater than 0.05) respectively. Experiments with animals showed that tablet cucumber vine compound possessed persistently decreasing effect on the blood pressure and marked effect on increasing coronary blood flow and improving myocardial contraction. Clinical observation and toxicological test proved that tablet cucumber vine compound had no toxicity and had few side effects and that it was an effective, safe medicine for essential hypertension.

[Protective effect of extracts from Aloe vera L. var. chinensis (Haw.) Berg. on experimental hepatic lesions and a primary clinical study on the injection of in patients with hepatitis]

The injection(10-15 ml/kg/d, ip x 4), total glycoside (125-225 mg/kg/d, ip x (3-4); 600 mg/kg/d, ig x 3) and crystal III (120 mg/kg/d, ip x 4) of Aloe vera var. chinensis were found to be effective in lowering the elevated sGPT induced by CCl4, thioacetamide and D-aminogalactose in mice or rats. It was also observed that these agents could protect hepatic cells from the CCl4-induced injury. When dogs were given in with Aloe injection of 0.1 ml/kg/d x 180, no toxicity was noted. The total effective sGPT-lowering rate of Aloe injection on 38 patients of chronic hepatitis with positive HBsAg was 86.8%.