Association analysis between carcass weight and meat quality of Bamei pigs.

A total of 48 crossbred Bamei pig carcasses were divided into three groups (A, 60-69 kg; B, 70-79 kg; and C, 80-90 kg) to investigate the influence of carcass weight on meat quality. The intramuscular fat content of the three groups increased from 2.20% (Group A) to 4.14% (Group C). Group B had higher drip loss (6.83%, P < 0.05) than the other two groups. Warner-Bratzler shear force decreased with increasing weight (61.16 > 51.63 > 43.64 N, P < 0.05). No significant differences were observed in meat color, cooking percentage, and water holding capacity among the three groups. The polyunsaturated fatty acids/saturated fatty acids ratio in group B (0.23) was significantly higher than that in the other two groups. In conclusion, our results suggested that a carcass weight of 70-79 kg is suitable for the production of Bamei pigs.

Comparison between meat quality of Hanzhong White pigs and carcass weight.

A total of 48 carcasses of crossbred Hanzhong White pigs were divided into 3 groups (I, 90-99 kg; II, 100-109 kg; III, 110-119 kg) to investigate the influence of carcass weight on meat quality. The intramuscular fat content of the 3 groups increased from 1.90 to 4.90%; for meat color, Warner-Bratzler shear force, drip loss, and oxidation-type muscle fiber percentage, and muscle fiber diameter of the longissimus lumborum, the indices in group II and group III were better than those in group I (P < 0.05). The saturated fatty acid and polyunsaturated fatty acid percentages of the longissimus lumborum muscle (2.80 and 37.30%, respectively) in group II were significantly lower than those in the other 2 groups, while the monounsaturated fatty acid percentage was the highest (59.10%). In conclusion, our results suggest that a carcass weight of 100-109 kg is sufficient to produce acceptable meat quality of Hanzhong White pigs.

[Status analysis of patients with hypertension in 22 community health centers of Shenzhen Futian District].

OBJECTIVE: To investigate current situation of blood pressure control in patients with hypertension in 22 community health centers of Shenzhen Futian District, and to find out related factors which affect blood pressure control. METHODS: In the study, 10 020 cases with essential hypertension that had been registered in 22 Community Health Centers were selected as cases for the survey. The questionnaires, physical examinations, and laboratory tests were used to obtain the patients' baseline data. RESULTS: The mean blood pressure (median) levels were 142/86 mmHg (1 mmHg=0.133 kPa). Those of the males were higher than those of the females (142/86 mmHg vs. 140/85 mmHg, ZSBP=-6.14,ZDBP=-9.93,P<0.001), the systolic blood pressure increased with age. The overall blood pressure control rate was 40.2%. The blood control rates were different with different gender, body mass index (BMI) and waist circumference. The majority of the patients took single antihypertensive drug, and the proportion accounted to 54.4%. Regression analysis showed that gender, age, hyperlipidemia, smoking, and waist circumference were the main factors that affected blood pressure control. CONCLUSION: The blood control rate was low in these communities. Patients with high blood pressure often merge a variety of factors that affect blood pressure control, and at the same time of antihypertensive therapy for the patients, we should pay attention to the control of these factors.

[Preliminary clinical effect evaluation of digital head and neck radiotherapy oral positioning stents].

Objective: To develop a designing software of digital oral positioning stent for radiotherapy of head and neck, and to compare its clinical effect with traditional oral positioning stents made by lost wax process. Methods: Thirty patients with nasopharyngeal cancer who received oral examination before radiotherapy in the prosthodontics department from July to December, 2021, were selected and divided into three groups according to the patients' wishes, 10 per group: one group without radiotherapy oral positioning stents, one group with traditional oral positioning stents (traditional stents group), and the third group with digital oral positioning stents (digital stents group). Patients' ages range from 20 years old to 71 years old. There were 15 males and 15 females involved in this study. The manufacturing time and comfort of the two positioning stents were evaluated, and the radiation doses of the radiotherapy target areas and surrounding healthy tissues were statistically analyzed at the end of radiotherapy. Results: The manufacturing time of digital stents group [(209±7) min] was much less than that of traditional stents group [(490±10) min] (t=69.85, P<0.001). The comfort of patients' wearing of digital stents [first wearing: 5 (3, 6) score; at the end of radiotherapy: 4 (3, 5) score] was better than that of traditional ones [first wearing: 7 (3, 7) score; at the end of radiotherapy: 7 (3, 7) score] (U=22.00, P=0.033; U=20.50, P=0.023). There was no significant differences in the target radiation doses among the three groups, and the radiation doses of tongue [traditional stents group: (36.74±5.45) Gy; digital stents group: (35.96±4.98) Gy] and mandible [traditional stents group: (35.46±4.19) Gy; digital stents group: (35.34±3.98) Gy] were significantly lower in the patients wearing oral positioning stents than in the patients without oral positioning stents [tongue: (41.49±4.46) Gy; madible: (39.32±3.52) Gy] (P<0.05). Conclusions: Oral positioning stents for nasopharyngeal carcinoma radiotherapy could greatly reduce the exposure doses of tongue and madible of patients. Digital oral positioning stents designed and manufactured by independently developed software had higher production efficiency than the traditional method, and patients' evaluation of comfort was better.

cDNA, genomic sequence cloning and overexpression of the ribosomal protein S13 gene in the giant panda (Ailuropoda melanoleuca).

The cDNA and the genomic sequence of ribosomal protein S13 (RPS13) of the giant panda (Ailuropoda melanoleuca) was cloned using reverse transcription-polymerase chain reaction (RT-PCR) and touchdown-PCR, respectively. These two sequences were sequenced and analyzed, and the cDNA of the RPS13 gene was overexpressed in Escherichia coli BL21. We compared the nucleotide sequences of the coding region and the amino acid sequences with those of seven other mammalian species retrieved from GenBank. The cDNA fragment of the RPS13 cloned from the giant panda is 496 bp in size, containing an open-reading frame of 456 bp, encoding 151 amino acids. The length of the genomic sequence is 2277 bp, with five exons and four introns. The coding sequence shows a high degree of homology to those of Homo sapiens, Bos taurus, Canis lupus familiaris, Macaca mulatta, Mus musculus, Rattus norvegicus, and Pan troglodytes; the degree of homology was 91.23, 94.30, 94.74, 92.11, 87.94, 87.72, and 91.45%, respectively. The homologies for the deduced amino acid sequences reached as high as 99%. Primary structure analysis revealed that the molecular weight of the putative RPS13 protein is 17.22325 kDa, with a theoretical pI of 10.42. Based on topology prediction, there is one protein kinase C phosphorylation site, one casein kinase II phosphorylation site, two N-myristoylation sites, and one ribosomal protein S15 signature in the RPS13 protein of the giant panda. The RPS13 gene can be expressed in E. coli and the RPS13 protein fused with the N-terminally GST-tagged form, which gave rise to the addition of an expected 43-kDa polypeptide.

cDNA, genomic sequence cloning and overexpression of ribosomal protein gene L9 (rpL9) of the giant panda (Ailuropoda melanoleuca).

The ribosomal protein L9 (RPL9), a component of the large subunit of the ribosome, has an unusual structure, comprising two compact globular domains connected by an α-helix; it interacts with 23 S rRNA. To obtain information about rpL9 of Ailuropoda melanoleuca (the giant panda) we designed primers based on the known mammalian nucleotide sequence. RT-PCR and PCR strategies were employed to isolate cDNA and the rpL9 gene from A. melanoleuca; these were sequenced and analyzed. We overexpressed cDNA of the rpL9 gene in Escherichia coli BL21. The cloned cDNA fragment was 627 bp in length, containing an open reading frame of 579 bp. The deduced protein is composed of 192 amino acids, with an estimated molecular mass of 21.86 kDa and an isoelectric point of 10.36. The length of the genomic sequence is 3807 bp, including six exons and five introns. Based on alignment analysis, rpL9 has high similarity among species; we found 85% agreement of DNA and amino acid sequences with the other species that have been analyzed. Based on topology predictions, there are two N-glycosylation sites, five protein kinase C phosphorylation sites, one casein kinase II phosphorylation site, two tyrosine kinase phosphorylation sites, three N-myristoylation sites, one amidation site, and one ribosomal protein L6 signature 2 in the L9 protein of A. melanoleuca. The rpL9 gene can be readily expressed in E. coli; it fuses with the N-terminal GST-tagged protein, giving rise to the accumulation of an expected 26.51-kDa polypeptide, which is in good agreement with the predicted molecular weight. This expression product could be used for purification and further study of its function.

[Effects of pressure steam sterilization times on the accuracy of the digital intraoral scanning data].

Objective: To provide a scientific basis for the standardized operation of clinical disinfection by comparing and analyzing the influence of disinfection times on the accuracy of digital intraoral scanning. Methods: The author prepared 10 brand-new intraoral scanning heads (Trios, 3Shape, Denmark), scan the same plaster standard dentition model after 1, 20, 40, and 60 times of pressure steam sterilization, and obtained the data of four groups of experimental groups A, B, C, D, and scan the model 5 times repeatedly after each disinfection cycle of each scanning head. A model scanner (D2000, 3Shape, Denmark) was used to scan the standard dentition model, and the scan results were used as the control group data. Vernier calipers and measurement software were used to measure the arch length (the distance between the mesial cheek tips of the first molars on both sides of the maxillary) and the front and back length (the distance from the tongue protrusion of the right incisor to the buccal tip of the first molar on the right of the upper jaw) of the plaster model and the data of the 4 experimental groups. The line distance results of the 4 groups of experimental groups were compared for statistical analysis, and the trueness and precision values of the 4 groups of experimental groups were compared for statistical analysis. Results: The length of the arch across the 4 experimental groups increased with the increase in the number of disinfection (P<0.05), and there were statistical differences compared with the measurement results of the plaster model (P<0.05); the differences in the length of the dental arch were not statistically significant (P>0.05). The treness of the 4 experimental groups is statistically significant (P<0.05), and the trueness was from high to low in order of group A [(114.85±3.75) µm], group B [(124.65±3.85) µm], group C [(131.45±3.04) µm] and group D [(144.64±3.34) µm]; the precision of the 4 experimental groups was not statistically significant (P>0.05). Conclusions: The number of times of pressure steam sterilization can affect the accuracy of the scanning results of the digital intraoral scanner, and with the increase of the number of sterilizations, the error of the scanning results also tends to increase. The number of sterilizations has no effect on the repeatability of the digital scanning results. The increase in the number of times of pressure steam sterilization affects the accross of the arch but has no effect on the length of the dental arch, and the range of change of the length of the arch is within the clinically acceptable range. After 60 times of pressure steam sterilization, the accuracy of digital scan data can still meet clinical needs.

Giant panda ribosomal protein S14: cDNA, genomic sequence cloning, sequence analysis, and overexpression.

RPS14 is a component of the 40S ribosomal subunit encoded by the RPS14 gene and is required for its maturation. The cDNA and the genomic sequence of RPS14 were cloned successfully from the giant panda (Ailuropoda melanoleuca) using RT-PCR technology and touchdown-PCR, respectively; they were both sequenced and analyzed. The length of the cloned cDNA fragment was 492 bp; it contained an open-reading frame of 456 bp, encoding 151 amino acids. The length of the genomic sequence is 3421 bp; it contains four exons and three introns. Alignment analysis indicates that the nucleotide sequence shares a high degree of homology with those of Homo sapiens, Bos taurus, Mus musculus, Rattus norvegicus, Gallus gallus, Xenopus laevis, and Danio rerio (93.64, 83.37, 92.54, 91.89, 87.28, 84.21, and 84.87%, respectively). Comparison of the deduced amino acid sequences of the giant panda with those of these other species revealed that the RPS14 of giant panda is highly homologous with those of B. taurus, R. norvegicus and D. rerio (85.99, 99.34 and 99.34%, respectively), and is 100% identical with the others. This degree of conservation of RPS14 suggests evolutionary selection. Topology prediction shows that there are two N-glycosylation sites, three protein kinase C phosphorylation sites, two casein kinase II phosphorylation sites, four N-myristoylation sites, two amidation sites, and one ribosomal protein S11 signature in the RPS14 protein of the giant panda. The RPS14 gene can be readily expressed in Escherichia coli. When it was fused with the N-terminally His-tagged protein, it gave rise to accumulation of an expected 22-kDa polypeptide, in good agreement with the predicted molecular weight. The expression product obtained can be purified for studies of its function.

[Effects and mechanism of pyrroloquinoline quinine on mitochondrial function and cell survival of rat bone marrow mesenchymal stem cells under oxidative stress].

Objective: To observe the effects of pyrroloquinoline quinine (PQQ) on the mitochondrial function and cell survival of rat bone marrow mesenchymal stem cells (BMSCs) under oxidative stress, and to explore its mechanism. Methods: BMSCs of rats were cultured in vitro with Dulbecco's minimum essential medium/F12 medium containing fetal bovine serum in the volume fraction of 10% (hereinafter referred to as normal medium). The rat BMSCs of third to fifth passages in logarithmic growth phase were selected for the following experiments. (1) The cells were divided into normal control group, normal control+ PQQ group, hydrogen peroxide (H(2)O(2)) alone group, and H(2)O(2)+ PQQ group. The cells in normal control group were cultured in normal medium for 24 hours; the cells in normal control+ PQQ group were cultured in normal medium containing 100 µmol/L PQQ for 24 hours; the cells in H(2)O(2) alone group were cultured in normal medium containing 200 µmol/L H(2)O(2) for 24 hours; the cells in H(2)O(2)+ PQQ group were pre-incubated with normal medium containing 100 µmol/L PQQ for 2 hours, and then with H(2)O(2) added to the concentration of 200 µmol/L and cultured for 24 hours. The cell morphology of each group was observed under the inverted phase contrast microscope, and the cell survival rate was detected by cell count kit 8 method. (2) Five batches of cells were collected, and the cells of each batch were divided into normal control group, H(2)O(2) alone group, and H(2)O(2)+ PQQ group. The cells in each group received the same treatment as that in the corresponding group of experiment (1). After 24 hours of culture, one batch of cells was collected for apoptosis detection by flow cytometry, and the apoptosis rate was calculated. One batch of cells was subjected to mitochondrial membrane potential assay and JC-1 fluorescent staining observation using the JC-1 mitochondrial membrane potential detection kit and the inverted phase contrast fluorescence microscope, respectively. One batch of cells was collected for mitochondrial morphology observation under the transmission electron microscope. One batch of cells was subjected to catalase (CAT) and superoxide dismutase (SOD) activity assay by CAT activity assay kit and SOD activity assay kit, respectively. One batch of cells was subjected to Western blotting for determination of protein level of Epac1, adenine monophosphate activated protein kinase (AMPK), phosphorylated AMPK, cysteinyl aspartate-specific proteinase 3 (caspase-3), and cleaved caspase-3, and the phosphorylation level of AMPK and cleaved caspase-3/caspase-3 ratio were calculated. Six replicates were measured in each group for each index except for morphological observation. Data were statistically analyzed with one-way analysis of variance and independent sample equal variance t test. Results: (1) After 24 hours of culture, compared with those in normal control group (the cell survival rate was set to 100.0%), there was an increase in cell vacuole and a decrease in cell number in H(2)O(2) alone group, and the cell survival rate was significantly reduced to (74.3±2.9)% (t=6.39, P<0.01). Compared with those in H(2)O(2) alone group, the cell morphology of H(2)O(2)+ PQQ group was significantly improved, and the cell survival rate was significantly increased to (116.9±4.2)% (t=6.92, P<0.01); the cell survival rate in normal control+ PQQ group was (101.2±1.1)%, close to that of control group (t=1.06, P>0.05). (2) After 24 hours of culture, compared with (13.6±1.0)% in normal control group, the apoptosis rate of cells in H(2)O(2) alone group was significantly increased to (37.1±2.0)% (t=10.57, P<0.01). Compared with that in H(2)O(2) alone group, the apoptosis rate of cells in H(2)O(2)+ PQQ group was significantly declined to (17.0±0.7)% (t=9.49, P<0.01). (3) After 24 hours of culture, compared with those in normal control group, the mitochondrial membrane potential of cells in H(2)O(2) alone group was depolarized, the JC-1 fluorescent dye mainly existed in the cytoplasm in the form of monomer, which emitted green fluorescence, and a significant decrease in mitochondrial membrane potential was shown (t=4.18, P<0.01). Compared with those in H(2)O(2) alone group, the mitochondrial membrane potential of cells in H(2)O(2)+ PQQ group was increased to normal level (t=4.43, P<0.01), and the JC-1 fluorescent dye accumulated in mitochondria following the polarized mitochondrial membrane potential and emitted red fluorescence. (4) After 24 hours of culture, compared with that in normal control group, the mitochondrial structure of cells in H(2)O(2) alone group was disordered, with disappeared mitochondrial cristae and decreased mitochondrial matrix density. Compared with that in H(2)O(2) alone group, the mitochondrial structure of cells in H(2)O(2)+ PQQ group was regular and intact, with clearly visible mitochondrial cristae and increased mitochondrial matrix density. (5) After 24 hours of culture, compared with those in normal control group, the CAT activity of cells in H(2)O(2) alone group was significantly increased (t=4.54, P<0.05), and the SOD activity was significantly decreased (t=3.93, P<0.05). Compared with those in H(2)O(2) alone group, the CAT activity of cells in H(2)O(2)+ PQQ group was obviously increased (t=8.65, P<0.01), while there was no significant change in the SOD activity (t=0.72, P>0.05). (6) After 24 hours of culture, compared with those in normal control group, the protein expression of Epac1 of cells in H(2)O(2) alone group was significantly decreased (t=4.67, P<0.01), while the AMPK phosphorylation level and the cleaved caspase-3/caspase-3 ratio were significantly increased (t=7.88, 3.62, P<0.01). Compared with those in H(2)O(2) alone group, the protein expression of Epac1 and the AMPK phosphorylation level of cells in H(2)O(2)+ PQQ group were both significantly increased (t=4.34, 16.37, P<0.01), while the cleaved caspase-3/caspase-3 ratio was significantly declined (t=3.17, P<0.05). Conclusions: Pretreatment with PQQ can improve the mitochondrial function, reduce cell apoptosis rate, and enhance cell survival rate of rat BMSCs under oxidative stress, which may be related to the up-regulation of Epac1 protein expression, activation of AMPK signaling pathway, and down-regulation of cleaved caspase-3 protein level.

Induction of esophageal cancers by nitenpyram (NIT) in rats.

OBJECTIVE: This study was made to investigate and evaluate the safety and carcinogenicity of nitenpyram (NIT) in rats. MATERIALS AND METHODS: A totally 50 male and 50 female SD rats were treated with NIT at 0, 800, 2400, and 7200 ppm, respectively, for 104 w. The growth, clinical signs, and survival rates, as well as the body and organ weights of these animals, were analyzed. Histopathological examination was also performed. RESULTS: Compared with the control group, survival rates at 104 w were significantly decreased in the 7200 ppm dose group, for both the male and female animals. The occurrence of esophageal squamous papilloma (ESP) was significantly increased in the treated animals. The occurrences of ESP for the 0, 800, 2400, and 7200 ppm NIT treatment groups were 0/39, 0/39, 3/35, and 9/27 for the male animals, and 0/43, 0/43, 6/49, and 12/33 for the female animals, respectively. For pre-neoplastic lesion of ESP, the occurrences of esophageal squamous hyperplasia for the 0, 800, 2400 and 7200 ppm NIT treatment groups were 0/39, 1/39, 10/35, and 9/27 for the male animals, and 0/43, 2/43, 15/49, and 17/33 for the female animals, respectively. The basal cell hyperplasia from mild to severe degrees was observed in the treatment groups. CONCLUSIONS: NIT exhibits carcinogenicity of ESP in the male and female rats after the two-year treatment.

Autoimmune limbic encephalitis in 39 patients: immunophenotypes and outcomes.

BACKGROUND: About 40% of patients with limbic encephalitis do not have detectable CNS antibodies. Some of these patients have immune-mediated limbic encephalitis, but their frequency is unknown. AIMS: (1) To determine the spectrum of limbic encephalitis identified on clinical grounds in a single institution, and compare it with that in patients referred for antibody analysis. (2) To correlate clinical outcomes with the cellular location of the autoantigens. METHODS: Prospective clinical case studies. Immunohistochemistry with rat brain, live hippocampal neurones, HeLa cells expressing Kv potassium channels and immunoblot. RESULTS: In 4 years, 17 patients were identified in the Hospital of the University of Pennsylvania, Philadelphia, USA, and the serum or CSF samples of 22 patients diagnosed elsewhere were also studied. 9 of our 17 (53%) patients had antibodies to known neuronal antigens (paraneoplastic or voltage gated potassium channels (VGKCs)) and 5 (29%) to novel cell-membrane antigens (nCMAg) typically expressed in the hippocampus and sometimes in the cerebellum. Considering the entire series, 19 of 39 (49%) patients had antibodies to known antigens, and 17 (44%) to nCMAg. Follow-up (2-48 months, median 19 months) was available for 35 patients. When compared with patients with antibodies to intraneuronal antigens, a significant association with response to treatment was found in those with antibodies to cell-membrane antigens in general (VGKC or nCMAg, p = 0.003) or to nCMAg (p = 0.006). CONCLUSIONS: (1) 82% of patients with limbic encephalitis prospectively identified on clinical grounds had CNS antibodies; (2) responsiveness to treatment is not limited to patients with VGKC antibodies; (3) in many patients (29% from a single institution), the autoantigens were unknown but were found to be highly enriched in neuronal cell membranes of the hippocampus; and (4) these antibodies are associated with a favourable outcome.

[Effects of human amniotic epithelial stem cells-derived exosomes on healing of wound with full-thickness skin defect in rats].

Objective: To investigate the effects of human amniotic epithelial stem cells-derived exosomes on healing of wound with full-thickness skin defect in rats. Methods: (1) Human amniotic epithelial stem cells were isolated from the amnion tissue of 5 full-term pregnant women in Department of Obstetrics of our hospital by the method of trypsin digestion, and their morphology was observed. The third passage of cells were stained with rhodamine-phalloidin for cytoskeleton observation. The third passage of cells were identified with flow cytometry through the detection of expressions of cell surface markers CD29, CD31, CD34, CD90, CD105, SSEA3, SSEA4 and immunity-related marker human leukocyte antigen-D related site (HLA-DR). The third passage of cells were also assessed the ability of adipogenic and osteogenic differentiation. (2) The third passage of human amniotic epithelial stem cells were cultured in DMEM medium supplemented with 10% exosome-free fetal bovine serum. Exosomes were isolated from culture supernatant by the method of ultracentrifugation and represented with scanning electron microscope for morphologic observation. (3) Six adult SD rats were anesthetized, and four 1 cm×1 cm sized wounds with full-thickness skin defect were made on the back of each rat. The wounds on the back of each rat were divided into control group, 25 µg/mL exosomes group, 50 µg/mL exosomes group, and 100 µg/mL exosomes group according to the random number table (with 6 wounds in each group), and a total volume of 100 µL phosphate buffered saline, 25 µg/mL exosomes, 50 µg/mL exosomes, and 100 µg/mL exosomes were evenly injected around the wound through multiple subcutaneous sites, respectively. The wound healing rate was calculated based on measurement on post injury day (PID) 7, 14, and 21. On PID 21, the healed wound tissue of each group was collected and stained with HE to observe and count skin accessories, and the arrangement of collagen fibers was observed with Masson staining. Data were processed with analysis of variance for repeated measurement, analysis of variance of randomized block design, one-way analysis of variance, and Bonferroni test. Results: (1) The cells, which were isolated and cultured, displayed typical cobblestone morphology with many microvilli on cell surface. Among the cells, the positive expression rates of CD29, CD90, SSEA3, and SSEA4 were above 50.0%, and the rate of CD105 was 8.0%, while the rates of CD31, CD34, and HLA-DR were almost 0. The cells could differentiate into adipocytes and osteoblasts. The above results revealed that the cells cultured were human amniotic epithelial stem cells. (2) Human amniotic epithelial stem cells-derived exosomes were round or oval vesicles with diameter from 50 to 150 nm. (3) On PID 7 and 21, wound healing rates of the four groups were close (with P values above 0.05). On PID 14, wound healing rates of 50 and 100 µg/mL exosomes groups were (89.8±4.3)% and (92.0±4.6)% respectively, significantly higher than the wound healing rate of control group [(80.3±6.4)%, P<0.05 or P<0.01]. Moreover, the wound healing rate of 100 µg/mL exosomes group was significantly higher than that of 25 µg/mL exosomes group [(83.3±5.1)%, P<0.05]. On PID 21, the numbers of skin accessories in 50 and 100 µg/mL exosomes groups were 4.3±1.4 and 5.1±1.6 respectively, obviously more than those of control group and 25 µg/mL exosomes group (respectively 1.4±0.5 and 1.8±0.6, with P values below 0.01). Well reorganized collagen fibers were observed just in the healed wound tissue of 50 and 100 µg/mL exosomes groups. Conclusions: Human amniotic epithelial stem cells-derived exosomes can promote healing of wound with full-thickness skin defect in rats.

Accumulation of poly-beta-hydroxybutyrate in cyanobacterium Synechocystis sp. PCC6803.

Accumulation of poly-beta-hydroxybutyrate (PHB) by photoautotrophic microorganisms makes it possible to reduce the production cost of PHB. The Synechocystis sp. PCC6803 cells grown in BG11 medium under balanced, nitrogen-starved or phosphorus-starved conditions were observed by transmission electron microscope. Many electron-transparent granules in the nitrogen-starved cells had a diameter up to 0.8 micron. In contrast, the number of granules in the normally cultured cells decreased obviously and only zero to three much smaller granules were in each cell. These granules were similar to those in bacteria capable of synthesizing PHB. They were proved to be PHB by gas chromatography after subjecting the cells to methanolysis. Effects of glucose as carbon source and light intensity on PHB accumulation in Synechocystis sp. PCC6803 under nitrogen-starved cultivation were further studied. Glucose and illumination promoted cell growth but did not favor PHB synthesis. After 7 days of growth under nitrogen-starved photoautotrophic conditions, the intracellular level of PHB was up to 4.1% of cellular dry weight and the PHB concentration in the culture broth was 27 mg/l.

Lymphogenous cyst-vein shunt in the management of chylothorax and chylorrhea.

A 36 year-old woman developed marked lymphedema and chylous cysts of the lower abdominal wall, groin, labia, accompanied by chylorrhea. After cyst excision and transplantation of the greater omentum, a left chylothorax occurred. After thoracic duct ligation and left pleurodesis, pleural effusion recurred and worsened. Lymphangioscintigraphy and conventional lymphography suggested that undrained enlarged retroperitoneal lymphatics in the right iliac fossa had disrupted and lymph had leaked into the left chest from the right iliac fossa. Treatment by a lymphatic cyst-vein anastomosis redirected excess chylous lymph into the blood circulation and chylothorax initially remitted. Several years later with recurrence of chylorrhea, the anastomosis was found to be occluded. After a second operative connection between a lymphogenous cyst and the greater saphenous vein, chylorrhea subsided and chylothorax has remitted for more than 4 years.

Isolation, chemical and biological characterization of margaratensin, a neurotensin-related peptide from the skin of Rana margaratae.

A new neurotensin (NT)-related peptide, margaratensin, was obtained by Sep-Pak C18 and RP-HPLC from methanol extracts of the skin of Chinese frog Rana margaratae. The structure of the peptide has been determined to be Asp-Lys-Arg-Pro-Tyr-Ile-Leu-His-Glu, which is found to be homologous to the COOH-terminal sequence of NT, but has an extra His-Glu at the COOH-terminus. The synthetic preparation was shown to be indistinguishable from the native peptide during HPLC, amino acid analysis and bioassay. Margaratensin exhibited a hypotensive effect in the rat but the response was weaker than NT. The peptide could induce a potent and reproducible contractile activity on GPI which was different from xenopsin, another NT-related peptide from amphibian skin.

Isolation and structure of ranamargarin, a new tachykinin from the skin of Chinese frog Rana margaratae.

A new tetradecapeptide, ranamargarin, has been isolated by Sep-Pak C18 and HPLC from methanol extracts of the skin of the Chinese frog Rana margaratae. The sequence of the peptide is: Asp-Asp-Ala-Ser-Asp-Arg-Ala-Lys-Lys-Phe-Tyr-Gly-Leu-Met-NH2. This structure has been confirmed by synthesis. The peptide is the largest among the amphibian tachykinins and its N-terminal amino acids are quite different from those of the other tachykinins. The formation of the sulfoxide and peak-splitting of ranamargarin during purification procedures are briefly discussed.