[Posterior arthroscopic subtalar arthrodesis for symptomatic adult talocalcaneal coalition].

Objective: To investigate the functional outcomes of posterior arthroscopic subtalar arthrodesis (PASTA) for adult patients presenting with symptomatic talocalcaneal coalition. Methods: The study was a retrospective case-series research.The data of 17 adult patients (17 feet) with symptomatic talocalcaneal coalitions,treated with PASTA from March 2018 to February 2022 in Xuzhou Central Hospital were collected.This procedure involved 10 males and 7 females,aged (42.4±7.5) years(range:31 to 58 years).There were 9 cases on the right side and 7 cases on the left side.According to the Rozansky classification,there were 4 cases of type Ⅰ,7 cases of type Ⅱ, 3 cases of type Ⅲ,3 cases of type Ⅳ.The following items such as wound healing and bony union of the subtalar joint were observed.Clinical assessment was performed using pain visual analogue scale (VAS),American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot scores and 36-item short form health survey (SF-36) scores.The paired t test was used for data comparison. Results: The follow-up time was (24.8±6.9) months(range:12 to 40 months).There were no complications such as wound infection,deep vein thrombosis,nonunion,or screw breakage.One patient with preoperative spasm,relieved after the second surgical procedure (peroneal brevis tendon lengthening).The union time of the subtalar joint was (8.8±2.2) weeks(range:6 to 12 weeks).At the final follow-up,the VAS decreased from (6.4±1.3) to (1.3±0.9)(t=14.114,P<0.01), the AOFAS ankle-hindfoot score increased from (49.0±8.1) to (90.0±5.1)(t=38.782,P<0.01),and the SF-36 score increased from (50.8±9.5) to (91.0±4.9)(t=20.468,P<0.01). Conclusion: PASTA for adult patients presenting with symptomatic talocalcaneal coalition offers advantages of minimal trauma,fast recovery,and few complications,which is an effective method.

The subfamily Xerocomoideae (Boletaceae, Boletales) in China.

Xerocomoideae is an ecologically and economically important Boletaceae subfamily (Boletales) comprising 10 genera. Although many studies have focused on Xerocomoideae in China, the diversity, taxonomy and molecular phylogeny still remained incompletely understood. In the present study, taxonomic and phylogenetic studies on Chinese species of Xerocomoideae were carried out by morphological examinations and molecular phylogenetic analyses. Eight genera in Xerocomoideae, viz. Aureoboletus, Boletellus, Heimioporus, Hemileccinum, Hourangia, Phylloporus, Pulchroboletus, and Xerocomus were confirmed to be distributed in China; 97 species of the subfamily were accepted as being distributed in China; one ambiguous taxon was tentatively named Bol. aff. putuoensis; two synonyms, viz. A. marroninus and P. dimorphus were defined. Among the Chinese accepted species, 13 were newly described, viz. A. albipes, A. conicus, A. ornatipes, Bol. erythrolepis, Bol. rubidus, Bol. sinochrysenteroides, Bol. subglobosus, Bol. zenghuoxingii, H. squamipes, P. hainanensis, Pul. erubescens, X. albotomentosus, and X. fuscatus, 36 known species were redescribed, and the other 48 species were reviewed. Keys to accepted species of Aureoboletus, Boletellus, Heimioporus, Hemileccinum, Hourangia, Phylloporus, and Xerocomus in China were also provided. Taxonomic novelties: New species: Aureoboletus albipes N.K. Zeng, Xu Zhang & Zhi Q. Liang, A. conicus N.K. Zeng, Xu Zhang & Zhi Q. Liang, A. ornatipes N.K. Zeng, Xu Zhang & Zhi Q. Liang, Boletellus erythrolepis N.K. Zeng, R. Xue, S. Jiang & Zhi Q. Liang, Bol. rubidus N.K. Zeng, R. Xue, Y.J. Hao & Zhi Q. Liang, Bol. sinochrysenteroides N.K. Zeng, R. Xue & Kuan Zhao, Bol. subglobosus N.K. Zeng, R. Xue, S. Jiang & Zhi Q. Liang, Bol. zenghuoxingii N.K. Zeng, R. Xue, S. Jiang & Zhi Q. Liang, Hemileccinum squamipes N.K. Zeng, Chang Xu & Zhi Q. Liang, Phylloporus hainanensis N.K. Zeng, L.L. Wu, & Zhi Q. Liang, Pulchroboletus erubescens N.K. Zeng, Chang Xu & Zhi Q. Liang, Xerocomus albotomentosus N.K. Zeng, H.J. Xie, Chang Xu & Zhi Q. Liang, and X. fuscatus N.K. Zeng, H.J. Xie, Chang Xu & Zhi Q. Liang. Citation: Xue R, Zhang X, Xu C, Xie HJ, Wu LL, Wang Y, Tang LP, Hao YJ, Zhao K, Jiang S, Li Y, Yang YY, Li Z, Liang ZQ, Zeng NK (2023). The subfamily Xerocomoideae (Boletaceae, Boletales) in China. Studies in Mycology 106: 95-197. doi: 10.3114/sim.2022.106.03.

[Progress and thinking of minimally invasive technique in the treatment of chronic Achilles tendon rupture].

In recent years,the application of minimally invasive techniques in the treatment of chronic Achilles tendon rupture has become more and more mature,and it also faces many controversies and challenges.The concept of minimally invasive technique is to minimize the dissection of soft tissue around the Achilles tendon and reduce the occurrence of postoperative wound complications.Minimally invasive small incision surgery does not expose the Achilles tendon stump,and either tendon transposition or tendon transplantation can be achieved using this technique,but there is a risk of accidental injury to the peripheral nerve.There are two main categories of arthroscopic treatment of old Achilles tendon rupture:endoscopic flexor hallucis longus tendon transfer and endoscopic tendon bridging.The former has a certain effect on postoperative flexor digitorum strength,and the latter is used in large segment defects mostly. The scientific and reasonable application of minimally invasive techniques in the treatment of patients with chronic Achilles tendon rupture is the goal and direction of continuous struggle of foot and ankle surgeons in the future.

[Arthroscopic treatment of acute closed noninsertional rupture of Achilles tendon].

Objective: To investigate the clinical efficacy of arthroscopic treatment of acute closed noninsertional rupture of Achilles tendon. Methods: The clinical and imaging data of 30 patients (30 feet) with acute closed noninsertional rupture of Achilles tendon who were treated with all-inside arthroscopic technique at the Department of Hand and Foot Microsurgery,Xuzhou Central Hospital from June 2018 to June 2020 were analyzed retrospectively. There were 26 males and 4 females,aged (38.3±8.5)years old(range:19 to 66 years). There were 22 cases on the right side and 8 cases on the left side. The duration from injury to surgery was (2.1±1.4) days (range:1 to 7 days).All patients were treated with all-inside arthroscopic technique.The function of the ankle and the foot was assessed using visual analogue scale (VAS),the American Orthopaedic Foot & Ankle Society (AOFAS) ankle hindfoot scale and the Achilles tendon total rupture score (ATRS). The Arner-Lindholm score system was used to evaluate the excellent and good rate of clinical effect. Paired sample t test or rank-sum test was used for data comparison. Results: The patients were followed up for (18.6±2.2)months(range:12 to 28 months).All the wounds healed at the first stage.No complication such as infection,sural nerve injury or re-rupture happened.Two patinets felt mild pain after a long time exercise, and were alleviated by microwave therapy and stretching the Achilles tendon consistently.Another patient was unable to do a sustained single stance heel raise,which was recovered after repeated function practice.At the last follow-up,the VAS (M(IQR)) decreased from 6(5) preoperatively to 0(1)(Z=6.512,P<0.01),the AOFAS ankle hindfoot scale improved from 60.6±8.3 preoperatively to 96.3±4.8(t=-29.774,P<0.01),and the ATRS improved from 61.7±7.8 preoperatively to 97.1±2.3 (t=-53.661,P<0.01).According to the Arner-Lindholm score system,27 cases were excellent,3 cases were good,and the excellent and good rate was 100%. Conclusions: The all-inside arthroscopic technique not only ensures the quality of tendon ananstomosis,but also avoids injury to the sural nerve.It has the advantages of small trauma,faster recovery and fewer complications.

[The reconstruction of Myerson type â ¢ chronic Achilles tendon rupture by using the total arthroscopic technique combined with free semitendinosus tendon and gracilis tendon autograft].

Objective: To evaluate the clinical outcome of the reconstruction of Myerson type Ⅲ chronic Achilles tendon rupture by using the total arthroscopic technique combined with free semitendinosus tendon and gracilis tendon autograft. Methods: Clinical data of 32 patients(32 ankles) with Myerson type Ⅲ chronic Achilles tendon rupture who were treated by using the total arthroscopic technique combined with free semitendinosus tendon and gracilis tendon autograft at Department of Hand and Foot Microsurgery, Xuzhou Central Hospital from September 2013 to September 2018 were analyzed retrospectively.There were 28 males and 4 females, aged 45.5 years old(range: 22 to 69 years old), 12 cases in the right side and 20 in the left.All patients were treated by using the total arthroscopic technique combined with free semitendinosus tendon and gracilis tendon autograft for Myerson type Ⅲ chronic Achilles tendon rupture reconstruction.The functional recovery of the ankle was evaluated according to ankle-hindfood score of American Orthopaedic Foot and Ankle Society (AOFAS) Ankle Hindfoot Scale, Achilles tendon total rupture score (ATRS), visual analogue scale (VAS).Arner-Lindholm score was used to evaluate the excellent and good rate.The quantitative data were compared using t-test or Wilcoxon test. Results: The 32 patients were followed up for 33 months (range: 15 to 72 months).No serious postoperative complications such as infection, sural nerve injury or tend re-rupture outcomes were reported.Three patients complained of mild pain when after a minimum sitting, walking or jogging, which were completely relieved by simple physical therapy or continuous stretching of Achilles tendon.At the last follow-up, the VAS decreased from 3 (5) (M (Q(R)) ) preoperative to 0 (3) (Z=1.357, P<0.01) and AOFAS ankle hindfoot scale improved from 58.6±13.5 preoperative to 95.5±4.0 (t=16.9, P=0.00), ATRS improved from 47.5±9.3 preoperative to 96.6±3.3 (t=25.661, P<0.01).According to the score of Arner-Lindholm, 20 cases were excellent, 12 cases were good, and the excellent and good rate was 100%. Conclusion: The reconstruction of Myerson type Ⅲ chronic Achilles tendon rupture by using the total arthroscopic technique combined with free semitendinosus tendon and gracilis tendon autograft has the advantages of safety, reliability, effectiveness and minor injury.

Long noncoding RNA NORAD promotes the progression of retinoblastoma by sponging miR 136-5p/PBX3 axis.

The article "Long noncoding RNA NORAD promotes the progression of retinoblastoma by sponging miR-136-5p/PBX3 axis, by X.-L. Yang, Y.-J. Hao, B. Wang, X.-L. Gu, X.-X. Wang, J.-F. Sun, published in Eur Rev Med Pharmacol Sci 2020; 24(3):1278-1287. DOI: 10.26355/eurrev_202001_20185. PMID: 32096159" has been withdrawn from the authors. The Publisher apologizes for any inconvenience this may cause.

Long noncoding RNA NORAD promotes the progression of retinoblastoma by sponging miR-136-5p/PBX3 axis.

OBJECTIVE: The specific roles of long noncoding RNAs (lncRNAs) have been found in human cancers, including retinoblastoma (RB). However, the function of lncRNA-NORAD has not been reported in RB. Therefore, the regulatory mechanism of lncRNA-NORAD was investigated in the development of RB. PATIENTS AND METHODS: The experimental tissues were collected from 24 RB patients and 6 patients with ruptured globes. The average age of all patients was 2.78 years (range, 2 months to 11 years). The mRNA and protein expression was measured by Real Time-quantitative Polymerase Chain Reaction (RT-qPCR) and Western blot analysis. The functional mechanism of NORAD was assessed by Cell Counting Kit-8 (CCK-8), transwell, and Dual-Luciferase reporter assays. RESULTS: Upregulation of NORAD and downregulation of miR-136-5p were found in RB. Functionally, knockdown of NORAD and miR-136-5p overexpression restrained RB cell viability, invasion, and migration. In addition, NORAD acts as a ceRNA of miR-136-5p in RB. MiR-136-5p was found to directly target PBX3. Furthermore, knockdown of PBX3 inhibited the progression of RB. More importantly, the NORAD/miR-136-5p axis is involved in RB progression by mediating PBX3. CONCLUSIONS: LncRNA NORAD, serving as a ceRNA of miR-136-5p, accelerates RB progression by upregulation of PBX3.

[A case of gout secondary to primary myelofibrosis].

A 52-year-old man was referred to our department with a 2-year history of polyarthritis. He was diagnosed as gout due to acute arthritis of bilateral feet dorsum 2 years ago,but he didn't receive any standard treatment. 1 year ago,there were more and more joints evolved during the gout attack, and many subcutaneous nodules occurred. When he presented to our clinic 1 month ago,the urate acid level was as high as 715 µmol/L. Moreover, we could find bone erosion in the X rays of his hand and foot,as well as synovitis,double contour sign and tophus on the ultrasound examination. The diagnosis of gout was clearly and definitely. However, he had leukocytosis and thrombocytosis for 4 years in the past history, and the urate acid level was only 400 µmol/L at that time. He also had well-controlled hypertension. The family history was unremarkable. Furthermore, we found megalosplenia on his physical examination. The bone marrow examination showed myelofibrosis and JAK2 V617F gene was positive. He was diagnosed as primary myelofibrosis and treated with interferon-α, together with urate acid-lowing therapy (febuxostat 60 mg once daily). Following-up for 1 year,the dosage of febuxostat decreased to 40 mg once daily, and the patient didn't have gout attack again, some of the tophus diminished, and the urate acid level ranged from 400 to 500 µmol/L. Gout is a common disease in clinical practice,usually combined with metabolic syndrome,chronic renal failure and specific drugs using (diuretic and calcineurin inhibitors). However,it is relatively rare to see gout associated with myeloproliferative diseases, including polycythemia vera, primary thrombocythemia, primary myelofibrosis and chronic myelocytic leukemia. In these diseases, the turnover of nucleic acids is greatly augmented, and an excess of purine metabolites, including uric acid, is released. In the natural course of gout, the appearance of tophus from the first onset of arthritis usually takes several years. This patient only had one traditional risk factor, but his urate acid level was remarkably high and he developed tophus in a short term. After treatment of primary myelofibrosis, the symptom of gout partially alleviated. Careful physical examination and medical history taking lead to the diagnosis of secondary gout, which should be reminded in the daily practice.

Repair and sensory reconstruction of the children's finger pulp defects with perforator pedicled propeller flap in proper digital artery.

OBJECTIVE: This study was designed to investigate the clinical effects of adopting perforator pedicled propeller flap in the proper digital artery for treatment and sensory reconstruction of finger pulp defects in children. PATIENTS AND METHODS: Perforator pedicled propeller flap of proper digital arteries in thirty-one fingers from twenty-three children patients were selected for repairing the pulp defects on the 2nd to the 5th fingers. All cases were treated from September 2012 to December 2013. To properly reconstruct the pulps' feeling we needed the dorsal branch of the proper digital nerve in the flap to be consistent with the broken end of proper digital nerve in pulps' wound. A free skin graft was carried out with full-thickness skin taken from the medial thigh for flap donor area. We scheduled two post-operation return visits, one in six months and the second visit in twelve months following the operation. Parents' satisfaction with the postoperative appearance of their children's fingers was assessed based on Michigan Hand Outcome Questionnaire. RESULTS: All operations were performed successfully and all wounds healed in the first period and all flaps survived. During the final follow-up, the shape recovery of flaps and their donor areas were examined and satisfactory results were obtained. All pulps were full and round without any obvious pigmentation or scar contracture. The sensory recovery of pulps was achieved S3+, and the two-point discrimination was 4.5 to 6.0 mm (with 5.1 mm being the average value). Parents' satisfaction with the postoperative results was very promising with twenty-one cases of very satisfied and two cases of satisfied parents. CONCLUSIONS: The operation method used in this study demonstrated to be a safe and reliable procedure producing a very good flap blood supply as well as excellent sensory recovery and satisfactory postoperative appearance.

Parasitic infections in the East Asian finless porpoise Neophocaena asiaeorientalis sunameri living off the Chinese Yellow/Bohai Sea coast.

Parasitic disease is among the major causes of health problems in marine mammals. However, little information on parasitic species composition and infection levels in finless porpoises (Neophocaena spp.) is available. In this study, we report the first systematic survey on parasitic infections in the East Asian finless porpoise N. asiaeorientalis sunameri (EAFP) living off the Chinese Yellow/Bohai Sea coast. Using both morphological and molecular methods, 5 parasitic helminths were identified: Campula oblonga in the liver and pancreas; Synthesium seymouri in the pyloric stomach and duodenum ampulla; Anisakis pegreffii in the forestomach, main stomach, and esophagus; Halocercus sp. in the lungs; and Crassicauda magna in the mammary glands and muscle. Among these helminths, C. oblonga (80.7%), S. seymouri (80.7%), A. pegreffii (80.7%), and Halocercus sp. (77.4%) were the most prevalent, whereas C. magna (6.5%) were only observed in 2 EAFP individuals. All juvenile and adult EAFPs were parasitized by at least 3 parasites species (C. oblonga, S. seymouri, and A. pegreffii), whereas in neonates, only Halocercus sp. were detected. We observed no significant difference in parasite prevalence between males and females. In addition, A. pegreffii and C. magna represented new infection records in Neophocaena. A pathological examination associated with parasitic lesions in EAFPs showed damage or destruction of cells or tissues to some extent. This study represents the first systematic survey on parasitic infections in EAFPs, providing important and valuable parasitological information for the research and conservation of this coastal marine mammal.

Fine dissection of the tarsal tunnel in 60 cases.

The fine dissection of nerves and blood vessels in the tarsal tunnel is necessary for clinical operations to provide anatomical information. A total of 60 feet from 30 cadavers were dissected. Two imaginary reference lines that passed through the tip of the medial malleolus were applied. A detailed description of the branch pattern and the corresponding position of the posterior tibial nerve, posterior tibial artery, medial calcaneal nerve and medial calcaneal artery was provided, and the measured data were analyzed. Our results can be summarized as follows. I. A total of 81.67% of the bifurcation points of the posterior tibial nerve, which was divided into the medial and lateral plantar nerves, were located within the tarsal tunnel, not distal to the tarsal tunnel. II. The bifurcation points of the posterior tibial artery were all located in the tarsal tunnel. Almost all of the bifurcation points of the posterior tibial artery were lower than those of the posterior tibial nerve. The bifurcation point of the posterior tibial artery situated distal to the tarsal tunnel was not found. III. The number and the origin of the medial calcaneal nerves and arteries were highly variable.

[Systemic lupus erythmatosus and panniculitis presenting as multiple ulcers: one case report].

A 36-year-old woman had an 8-year history of systemic lupus erythematosus (SLE) and was being treated with 10 mg/d of prednisone. She presented with a 6-month history of intermittent fever and multiple painful multi skin erythematous macules in her button, hips and extremities that had slowly enlarged to 8 cm×4 cm in diameter. The lesions started as painful erythematous macules, which eventually ulcerated and scared. Laboratory tests showed leukopenia, protenuria, positive anti-double strand DNA and hypocomplementemia. Cultures of the bottom ulcer were E. Coli, fugus and Tuberculous mycobacteria were both negative. Biopsy was performed and revealed necrosis of epidermis, thrombus and cellulose degeneration in epidermis with neutrophils karyorrhexis and vasculitis. Her SLE was active, so she was prescribed antibiotics for 2 weeks and prednisone was added to 60 mg/d for a month. However her skin ulcers did not relieve. When prednisone was added to 120 mg/d with combination therapy of cyclophosphamide and hydroxychloroquine, her skin ulcer cicatrized gradually.

Neuroprotective effects of LBP on brain ischemic reperfusion neurodegeneration.

AIM: The present study was conducted to investigate whether LBP had a protective effect on cerebral ischemic reperfusion injury and to determine the possible mechanisms. MATERIALS AND METHODS: Male Kunming (KM) mice were used to make the model cerebral artery occlusion/reperfusion (MCAO/R). The behavioral test was used to measure neurological deficit scores for evaluation of ischemic reperfusion damage of brain. The change of electroencephalograph (EEG) was monitored by Model SMUP-E Bio-electric Signals Processing System. The infarction area of brain was assessed in brain slices with 2% solution of 2,3,5-triphenyl tetrazolium chloride (TTC). Spectrophotometric assay was used to determine the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT) and lactate dehydrogenase (LDH), contents of malondialdehyde (MDA) and adenosine triphosphate (ATP) of the brain. RESULTS: The results showed that LBP at doses of 20 and 40 mg/kg markedly decreased the neurological deficit scores and the infarction area in MCAO/R mice. At the same time, LBP significantly decreased MDA content, and increased SOD, GSH-Px, CAT, LDH activities in ischemic reperfusion brain. CONCLUSIONS: These suggest that LBP might act as a potential neuroprotective agent against the cerebral reperfusion-induced injury in the brain through reducing lipid peroxides, scavenging free radicals, and improving the energy metabolism.

Identification and expression analysis of components involved in rice Xa21-mediated disease resistance signalling.

Rice Xa21 gene encodes a receptor-like kinase that confers broad-spectrum resistance against Xanthomonas oryzae pv. oryzae (Xoo). Recently, a number of genes involved in the Xa21-mediated disease resistance pathway have been identified. Based on our previous data and the literature, we chose 16 candidate proteins and made corresponding antibodies. Using Western blotting, we systematically investigated the expression profile of the proteins in Xa21-mediated disease resistance response. We found nine proteins with altered expression. We further compared their expression in resistance, susceptible and mock responses, and found that GST expression was up-regulated during the resistance process, indicating GST is a positive regulator in resistance responses. ATPsB expression was down-regulated during both the resistance and susceptible response processes, although it was higher in the resistance response than that in the susceptible response. The total amount of MYB, GAPDH, CatB, Trx and NB-ARC proteins was lower in the resistance than in the susceptible response, but their abundance per unit bacteria in the resistance response was still higher than in the susceptible response, suggesting that these proteins might be positive regulators in the resistance response. In addition, expression of another ERF was induced by inoculation with bacterial blight pathogen, and expression of Zf-LSD1 was activated by wounding stress alone. Interestingly, most proteins showed similar altered expression patterns in the resistance and susceptible responses, but differed to some extents, implying that both responses might share common molecular mechanisms. This study revealed evidence of resistance-related protein expression, providing a foundation for better understanding of their functions.

B-mode ultrasonographic evaluation of the testis in relation to serum testosterone concentration in male Yangtze finless porpoise (Neophocaena phocaenoides asiaeorientalis) during the breeding season.

The use of ultrasonography as a noninvasive tool for assessing the reproductive status of the male Yangtze finless porpoise (YFP; Neophocaena phocaenoides asiaeorientalis) was validated by correlating ultrasonographically determined testicular volume (TV) and testicular parenchyma pixel intensity (PI) with serum testosterone (T) concentration. The testes of 13 free-ranging male YFPs from the Tian-e-Zhou Reserve and three captive animals from the Baiji Dolphinarium (Wuhan, China) were examined ultrasonographically during April 2008. Testis volume was determined using Lambert's formula for an ellipsoid. Testicular parenchyma PI was evaluated by analyzing testicular ultrasonograms using pixel analysis software (Image J). Serum T concentrations were determined using a single-antibody radioimmunoassay. The TV, PI, and serum T concentration were low and similar in animals with body length <133 cm, highest in those with body length >or=142 cm, and highly variable in those with body length from 133 to 141 cm. Both TV and PI were closely correlated with serum T concentration (r=0.91 and r=0.85, respectively; P<0.01), indicating a consistent association between structural and functional development of the testis. In conclusion, we inferred that puberty onset in male YFPs occurred when TV was >150 cm(3) and PI was >60 during the breeding season and that testicular ultrasonography and pixel analysis was an efficient, noninvasive, real-time tool to evaluate testicular function of live male YFPs.

Purification and characterization of a thermal stable antimicrobial protein from housefly larvae, Musca domestica, induced by ultrasonic wave.

This work describes the induction, purification and partial biochemical characterizations of an antimicrobial protein from the housefly larvae induced by ultrasonic wave. It has been purified to apparent homogeneity by ammonium sulfate precipitation followed by Sephadex G-75, Bio-gel P6 gel filtration, and CM-Sepharose Fast Flow cation exchange chromatography. The protein is a cationic protein with an apparent molecular weight of 16315 Da determined by no-denaturing electrophoresis and SDS-PAGE, respectively. Biochemical profile assays show that this protein has good thermal stability, and repeatedly frozen and defrosted durability. The optimum pH for antimicrobial activity is around pH5. The antimicrobial range of the protein includes Gram-positive, Gram-negative bacteria and some fungi. Results of the membrane permeability assays suggest that the probable mode of action of this protein is membrane-disrupting mechanism.

Studies on the antibacterial activities and mechanisms of chitosan obtained from cuticles of housefly larvae.

Chitosan was obtained from cuticles of the housefly (Musca domestica) larvae. Antibacterial activities of different Mw chitosans were examined against six bacteria. Antibacterial mechanisms of chitosan were investigated by measuring permeability of bacterial cell membranes and observing integrity of bacterial cells. Results show that the antibacterial activity of chitosan decreased with increase in Mw. Chitosan showed higher antibacterial activity at low pH. Ca2+ and Mg2+ could markedly reduce the antibacterial activity of chitosan. The minimum inhibitory concentrations of chitosans ranged from 0.03% - 0.25% and varied with the type of bacteria and Mw of chitosan. Chitosan could cause leakage of cell contents of the bacteria and disrupt the cell wall.

Low-temperature in situ large strain plasticity of ceramic SiC nanowires and its atomic-scale mechanism.

Large strain plasticity is phenomenologically defined as the ability of a material to exhibit an exceptionally large deformation rate during mechanical deformation. It is a property that is well established for metals and alloys but is rarely observed for ceramic materials especially at low temperature ( approximately 300 K). With the reduction in dimensionality, however, unusual mechanical properties are shown by ceramic nanomaterials. In this Letter, we demonstrated unusually large strain plasticity of ceramic SiC nanowires (NWs) at temperatures close to room temperature that was directly observed in situ by a novel high-resolution transmission electron microscopy technique. The continuous plasticity of the SiC NWs is accompanied by a process of increased dislocation density at an early stage, followed by an obvious lattice distortion, and finally reaches an entire structure amorphization at the most strained region of the NW. These unusual phenomena for the SiC NWs are fundamentally important for understanding the nanoscale fracture and strain-induced band structure variation for high-temperature semiconductors. Our result may also provide useful information for further studying of nanoscale elastic-plastic and brittle-ductile transitions of ceramic materials with superplasticity.

Effect of cryopreservation on apple genetic resources at morphological, chromosomal, and molecular levels.

Shoot tips of three apple genotypes, namely, Malus pumila cv. M26, Gala, and Hokkaido No. 9, were successfully cryopreserved using a modified encapsulation-dehydration method. As a result, in addition to a high survival rate and regeneration rate, the capacity of shoots regenerated from cryopreserved samples to root was enhanced. Eight M26 single-bud sibling lines were used to assess genetic stability. Although cytological examination revealed a ploidy difference in the noncryopreserved control, the ploidy constitution remained relatively stable during the period of cryopreservation. Amplified fragment length polymorphism (AFLP) assay was performed to detect DNA-level variation. No change in DNA fragment pattern and number was observed between the control and the cryopreserved samples. In addition, methylation-sensitive amplified polymorphism (MSAP) assay was carried out to investigate the DNA methylation status during the period of cryopreservation. It was found that cryopreservation induced a decrease in DNA methylation level.