[Clinical study of digital six-axis external fixation frame based on CT data for tibiofibular fractures].

Objective: To investigate the clinical effect of applying the digital six-axis external fixation frame based on CT data in the treatment of tibiofibular fractures. Methods: The clinical data of 43 patients with tibiofibular fractures treated by the self-developed digital six-axis external fixation frame based on CT data at Integrated Orthopedic Department of Traditional Chinese Medicine (TCM) and Western Medicine,HongHui Hospital from January 2018 to January 2021 were retrospective analysis.There were 27 males and 16 females,aged (36.0±9.4) years(range:25 to 50 years).AO classification:15 cases of 42A,11 cases of 42B, and 17 cases of 42C.There were 7 open fractures and Gustilo fracture classification:2 cases of type Ⅰ,4 cases of type Ⅱ,and 1 case of type Ⅲ.The two or three plane rings were connected with six connecting rods to form a complete six-axis external fixation frame,and the distal and proximal fracture blocks were connected to the distal and proximal rings by fixation pins,and the lengths of the six connecting rods needed to be adjusted were calculated by using the supporting software according to the CT data after surgery,and then the lengths of the connecting rods were adjusted one by one to complete the reduction of the fracture. The reduction accuracy of this six-axis external fixation brace was evaluated by measuring postoperative radiographs; postoperative recovery and complications were collected,the time of brace removal was recorded,and the function of the affected limb was evaluated according to the Johner-Wruhs score at the final follow-up. Results: Postoperative radiographs showed that all patients achieved satisfactory reduction with lateral displacement(M(IQR)) of 2.3(2.5) mm (range:0.3 to 7.3 mm),anteroposterior displacement of 2.1 (2.4) mm (range:0.3 to 5.7 mm),anteroposterior angulation of 2.5(2.4)°(range:0 to 5°),internal and external angulation of 2.1(1.5)°(range:0 to 4°), and no significant internal or external rotational deformity was detected on the exterior.On the second postoperative day,all patients were able to walk with partial weight-bearing on crutches. All 43 patients were followed up for more than 6 months,with a follow-up period of (33.3±7.3) weeks (range:24 to 42 weeks).The external fixation frame was removed after the fracture healed.The external frame was removed at 20(3)weeks (range:18 to 25 weeks) postoperatively. Up to the final follow up, no secondary fracture occurred in any of them.The Johner-Wruhs score of the affected limb at the last follow-up was excellent in 39 cases and good in 4 cases. Conclusion: The digital six-axis external fixator based on CT data for tibiofibular fractures has the advantages of precise reduction,firm fixation,simple operation,rapid fracture healing,and minimal trauma, which is a minimally invasive method for treating tibiofibular fractures,especially suitable for patients with poor skin and soft tissue conditions such as open injuries.

MicroRNA-4443 regulates monocyte activation by targeting tumor necrosis factor receptor associated factor 4 in stroke-induced immunosuppression.

BACKGROUND AND PURPOSE: MicroRNAs (miRNAs) have been demonstrated to play crucial roles in the early stage of acute ischaemic stroke (AIS). The purpose of this study was to investigate the expression patterns of miRNAs in peripheral blood mononuclear cells (PBMCs) from AIS patients and further explore related molecular mechanisms in stroke-induced immunodeficiency syndrome (SIDS). METHODS: The miRNA expression patterns of PBMCs were detected by miRNA microarray and validated by quantitative real-time polymerase chain reaction (qRT-PCR) in AIS patients and healthy controls. Bioinformatics methods and luciferase reporter assays were used to detect the downstream target genes. Following stimulation with lipopolysaccharide and interleukin-4, the expression of miR-4443, tumor necrosis factor receptor associated factor 4 (TRAF4) and the nuclear factor kappa B (NF-κB) pathway were evaluated. Furthermore, transfection with miR-4443 mimic or inhibitor in the monocytes was carried out to gain insight into the mechanisms in SIDS. RESULTS: Interleukin-10 in AIS patients was significantly higher than that of healthy controls. The miRNA microarray analysis and qRTPCR validation showed that only miR-4443 was upregulated expressed in PBMCs from AIS patients, especially in monocytes. miR-4443 was shown to directly interact with the 3' untranslated regions of TRAF4, resulting in suppression of TRAF4 protein expression. Furthermore, the expression of miR-4443 and TRAF4 was regulated by stimulation with lipopolysaccharide or interleukin-4. Additionally, overexpression of miR-4443 suppressed the TRAF4/Iκα/NF-κB signaling pathway to activate the expression of anti-inflammatory cytokines in monocytes. CONCLUSIONS: The increased expression of miR-4443 induced monocyte dysfunction by targeting TRAF4, which may function as a crucial mediator in SIDS.

[Application of a new type of angle-adjustable osteotomy guide in closing wedge distal femoral osteotomy].

Objective: To explore the feasibility of fast and accurate osteotomy using a new angle adjustable osteotomy guide (AAOG) in closing wedge distal femoral osteotomy(CWDFO). Methods: The clinical data of 14 patients (17 knees) with valgus knee treated with CWDFO at Department of Integrated Chinese and Western Medicine Orthopedics, Honghui Hospital, Xi'an Jiaotong University from January 2018 to July 2019 were analyzed retrospectively. There were 3 males and 11 females, aging (41.4±16.4) years (range: 18 to 56 years). The body mass index was (23.5±3.5) kg/m(2) (range: 18.1 to 28.9 kg/m(2)). The guide pins were placed with the assistance of the self-designed AAOG. Before the surgery, Solidworks software was used to calculate the correction angle and the osteotomy radius accurately. The osteotomy guide was adjusted according to these two parameters. During the surgery, the adjusted osteotomy guide was placed to the surface of bone closely and the guide pins were drilled into the bone through the guide holes. The position of the guide pins was confirmed under fluoroscopy. The osteotomy was finished under guide of pins and fixed with Tomofix plate (Synthes). The times and duration of placement of the guide pins, the times of X-ray examination, the planned and actual thickness of the osteotomy wedge, the top and bottom area of the osteotomy wedge, the posterior distal femoral angle(PDFA), the correction of the weight line, and the American Knee Society Score(AKSS) and Tegner scores were collected and compared by paired t test or Kruskal-Wallis non-parametric test. Healing time after osteotomy and complications were recorded. Results: The guide pins were successfully placed once in 10 knees, adjusted once in 5 knees and twice in 2 knees. The time spent in placing all the 6 pins was 82.4 seconds (range: 51 to 125 seconds), and the times of X-ray examination was 1.5 times (range: 1 to 5 times). The top and bottom areas of the osteotomy wedge were (5.52±0.52)cm(2) and (5.36±0.49)cm(2). PDFA was (85.2±2.6)° preoperatively and (85.5±1.4)° postoperatively (t=-0.401, P>0.05). The thickness of the osteotomy was (11.3±1.9)mm according to the preoperative plan, and the actual thickness was (8.1±1.7)mm. All the patients were followed up for 6 months after surgery and AKSS and Tegner scores improved significantly (all P<0.05). The correction of the weight lines was within the ideal range. Fractures of the hinge point occurred in 3 knees. All of the osseous healing without complications. Conclusion: The new osteotomy guide helps to place the guide pins rapidly and precisely according to the preoperative planning, which should be widely used in clinical applications with promising outcomes.

Impaired motor inhibition in developmental coordination disorder.

This study aimed to evaluate the 'inhibitory deficit' hypothesis of developmental coordination disorder (DCD). We adopted a multifaceted approach, investigating two distinct, yet complimentary facets of motor inhibition: action restraint and action cancellation. This was achieved using carefully constructed versions of the 'Go/No-go' and 'Stop-signal' tasks, respectively. The sample comprised 11 young adults with DCD aged between 18 and 30 years of age and 11 typically developing, age-matched controls. Participants completed both the 'Go/No-go' and 'Stop-signal' tasks to assess action restraint and action cancellation respectively. Individuals with DCD were less efficient than their typically developing peers at performing both action restraint and action cancellation, indicated by significantly reduced action restraint efficiency index scores on the 'Go/No-go' task and a trend towards longer stop-signal reaction times on the 'Stop-signal' task. This work clarifies disparate evidence speaking to the integrity of action restraint in DCD and provides the first account of action cancellation in DCD using a purpose-built measure. In support of the inhibitory deficit hypothesis of DCD, our results suggest that young adults with DCD experience broad difficulties with engaging inhibitory mechanisms during motor behaviour.

[Characterization analysis of gM, gL genes of varicella zoster virus in six provinces of China].

Objective: To analyze the genetic characterization of glycoprotein M(gM.),glycoprotein L(gL) of varicella zoster virus. Methods: According to the program of "Ministry of Science and Technology of China" , Based on the 12 suspected VZV patients monitored in Beijing (1 case), Shanghai (5 cases), Jilin (2 cases), Qinghai (1 case), Guangdong (2 case) and Sichuan (case) in 2007-2015. A total of 12 Vesicle fluid and throat swab samples were collected. Positive samples were identified by Agarose gel electrophoresis and two glycoprotein genes were amplified by polymerase chain reaction (PCR). Nucleotide sequences were determined and analyzed by PCR amplification of VZV positive specimens V-OKA-BK of the domestic varicella attenuated live vaccine and the Varilrix-1 of the imported attenuated live vaccine. Nucleotide sequences of VZV positive specimens, vaccine strains (V-OKA-BK, varilrix-1) and GenBank foreign wild strains (41 strains), parent strains (P-oka), vaccine strains (V-oka, Varilrix, Varivax) were compared using BioEdit and MEGA 5.0. Results: 12 specimens were VZV positive. Compared with the vaccine strains and the parent strains, the GM gene of 1 positive specimen had radical mutation at 86686 sites, which resulted in amino acid mutation, 5 positive specimens had base mutation at 87844 sites, and 30 strains of foreign wild strains had the same variation at 87 844 sites. 1 positive specimens of gL gene in 101245 sites had base mutation, and led to amino acid mutation, 6 positive specimens at 101624, 101625, 101626 sites had base of loss and the foreign wild strains in these 3 sites had the same variation. Compared with the vaccine strains, the nucleotide and amino acid homology of gM of 12 VZV positive specimens were 99.2%-100% and 98.2%-100%, respectively, and gL of those were 99.3%-100% and 98.6%-100%, respectively. Compared with 41 strains of foreign wild strains, homology of gM's nucleotides and amino acid were 99.3%-100% and 98.5%-100%, respectively; 99.1%-100% and 98.6%-100% for gL. The results of phylogenetic analysis showed that 7 VZV positive samples were on the same branch with 4 vaccine strains and p-oka strain. Based on gL, 12 VZV positive samples were on the same branch as the vaccine strains and p-oka strain. Conclusion: This study demonstrates that the genes of gM, gL are highly conserved and remain stable immunogen, which may be involved in the attenuation of VZV and need to be further researched.

Risk of hip fracture following stroke, a meta-analysis of 13 cohort studies.

This study systematically reviews prospective and retrospective cohort studies evaluating the risk of hip fracture following stroke. Stroke survivors are at high risk of hip fracture and had a 1.5-fold increased risk compared to stroke-free men and women of the same age. Hip fracture often occurs in ageing and female stroke patients. We performed a meta-analysis to summarize evidence from prospective and retrospective cohort studies about the risk of hip fracture following stroke. We identified English and non-English publications in MEDLINE and EMBASE using stroke and fracture as keywords to 31 December 2015. The data of the incidence of hip fracture were extracted to calculate raw incident rate in stroke survivors as well as risk of hip fractures in strokes comparing populations using a random-effects model. Subgroup analyses were performed to identify the potential influence of some factors. Six prospective and seven retrospective cohort studies were included, involving 512,214 stroke patients with 22,559 hip fractures. The pooled prevalence of hip fractures was 4.87 % (95 % CI, 4.05 to 5.68 %) in stoke patients. We conducted subgroup analysis according to sex, age, duration of follow-up, study design, and region, which showed that female (vs. male) stroke patients older than 70 years (vs. those less than 70 years) and duration of follow-up more than 2 years (vs. those less than 2 years) have higher proportions of hip fractures. Four studies showed that stroke patients had a significantly higher risk of hip fracture compared with the general population, while the other study had a non-significant higher risk. The overall prevalence of hip fracture was 3.28 % (3431 of 104,646) in stroke patients and 2.83 % (36,493 of 1,287,726) in general population, respectively, and the unadjusted combined relative risk of hip fracture was 1.54 (95 % CI, 1.06-2.25). Hip fractures often occur in ageing and female stroke patients.

C-reactive protein and risk of fracture: a systematic review and dose-response meta-analysis of prospective cohort studies.

UNLABELLED: This study systematically reviews prospective cohort studies evaluating the relationship between C-reactive protein (CRP) concentrations and subsequent fracture risk. The positive association cannot completely explain the existing evidence, and further studies are needed to demonstrate the shape of the association. INTRODUCTION: We aimed to perform a systematic review and dose-response meta-analysis of published prospective studies evaluating associations of high-sensitivity CRP (hs-CRP) levels with fracture risk in general populations. METHODS: We identified relevant studies by searching MEDLINE and EMBASE databases from their inception to May 20, 2014. We included published prospective studies evaluating the associations of hs-CRP levels with risk of fracture in general populations. Two reviewers working independently abstracted the data. RESULTS: Eight prospective cohort studies involving 34,840 participants and 3,407 incident fracture events were eligible for the present analyses. A meta-analysis of six prospective studies showed that the overall risk for incident fracture in a comparison of individuals in the top tertile with those in the bottom tertile of baseline hs-CRP levels was 2.14 [95% confidence interval (CI) 1.51-3.05, I(2) = 62.3%]. The moderate heterogeneous disappeared when one study was excluded. However, the remaining two studies reported inconsistent results. One study with the biggest sample size showed a U-shaped association for CRP and fracture risk (the association was positive when CRP > 1 mg/L). Similarly, another study reported that per doubling of CRP was positive only when CRP > 3 mg/L. CONCLUSION: In summary, the present analysis showed that the relationship between CRP concentrations and subsequent fracture risk is still inconsistent. The positive association cannot completely explain the existing evidence, and further larger prospective cohorts with more power are needed to demonstrate the shape of the association, especially for the relatively low CRP concentrations, such as less than 3 mg/L.

The Elimination Rate after Clozapine Overdose in Chinese Schizophrenia Patients: A Population Pharmacokinetics Model Study.

INTRODUCTION: The prescribing of clozapine in China is common because of its outstanding efficacy and low price. There have been many cases of clozapine overdose in China. However, studies about the pharmacokinetics after overdose in the Chinese have rarely been reported. Population pharmacokinetics (PopPK) can analyze sparse data, and it is appropriate to compute clozapine pharmacokinetics after overdose. METHODS: There were 47 clozapine overdose cases. We constructed a single-compartment first-order elimination PopPK model. We also considered some covariates that can influence the pharmacokinetics parameters. RESULTS: 21 cases were included in the analysis. When the reported toxic dosage was 3,740 mg, the elimination rate constant of the population was 0.0258(h(-1)). The elimination half-life was 26.9 h. The coefficient of random variation was 17%. DISCUSSION: PopPK can solve the problem of sparse data after overdose. The area under the concentration-time curve after clozapine overdose exhibited the "two peaks phenomenon." The reported toxic dosage could impact clozapine elimination after overdose. Delayed absorption of clozapine is the best explanation for this finding.

[A cross-sectional survey and analysis of influencing factors on the occurrence of post-burn psychological stress disorder in preschool children].

Objective: To explore the occurrence and influencing factors of post-burn psychological stress disorder in preschool children. Methods: This study was a multi-center cross-sectional survey. From January 2022 to February 2023, 85 preschool children (aged 1 to 6 years) with burns admitted to the Affiliated Hospital of North Sichuan Medical College, Nanchong Central Hospital, Suining Central Hospital, Guang'an People's Hospital, and Guangyuan Central Hospital who met the inclusion criteria were selected as respondents. A self-made general information questionnaire was used to investigate the children's general data including gender, age group, residential area, main caregiver and their education level, and family type, as well as the injury condition including cause of injury and burn severity. The Child Stress Disorders Checklist was used to investigate the occurrence of psychological stress disorder in children at 3 days to 1 month after injury, and the incidence rate was calculated. The children were classified according to their general data and injury condition, and the occurrence of psychological stress disorder in children at 3 days to 1 month after injury was recorded, and the influencing factors for post-burn psychological stress disorder in preschool children were screened. Results: A total of 85 questionnaires were distributed and 85 valid questionnaires were recovered, with an effective recovery rate of 100%. Among the children, there were 45 boys and 40 girls, with most children aged 1 to 3 years. There were slightly more children in rural areas than in cities. About half of the children were mainly cared for by their parents and grandparents, respectively, and the education level of the main caregivers was mainly high school/technical secondary school. The family type was mainly core family and extended family. The main cause of injury was hydrothermal scald, and the severity of burns was mainly moderate. The incidence rate of psychological stress disorder in this group of children at 3 days to 1 month after injury was 34.12% (29/85). There were statistically significant differences in the occurrence of psychological stress disorder in children with different age groups, causes of injuries, and burn severity at 3 days to 1 month after injury (with χ2 values​​of 9.18, 7.80, and 25.47, respectively, P<0.05); there were no statistically significant differences in the occurrence of psychological stress disorder in children with different genders, residential area, main caregivers, main caregivers' education levels, or family types at 3 days to 1 month after injury (P>0.05). Multivariate logistic regression analysis showed that age group and burn severity were independent influencing factors for the occurrence of psychological stress disorder in preschool children after burns (with odds ratios of 8.21 and 33.99, respectively, and 95% confidence intervals of 1.57-43.04 and 5.55-207.93, respectively, P<0.05), the older the child and the more severe the burn, the higher the possibility of the occurrence of psychological stress disorder. Conclusions: The incidence rate of psychological stress disorder is high in preschool children after burns. Age group and burn severity are independent influencing factors for the occurrence of post-burn psychological stress disorder in this type of children.

Complementary laboratory indices for predicting the disease status of patients with hepatitis B virus infection.

To identify complementary laboratory indices for determining the disease status of patients with hepatitis B virus. Subjects were divided into six groups: hepatitis B virus carrier, mild chronic hepatitis B, moderate chronic hepatitis B, severe chronic hepatitis B, fulminant hepatitis B and healthy controls. Serum alanine aminotransferase, total bilirubin and direct bilirubin were measured by an automatic analyser. The levels of T-cell immunoglobulin domain and mucin-domain-containing molecule-3, macrophage inflammatory protein 2, neutrophil gelatinase-associated lipocalin and inducible nitric oxide synthase were measured by ELISA. T-cell immunoglobulin domain, mucin-domain-containing molecule-3, macrophage inflammatory protein 2 and inducible nitric oxide synthase levels were significantly higher in patients with severe chronic hepatitis B compared with those in patients with mild and moderate chronic hepatitis B or fulminant hepatitis B (P < 0.05). When normal or abnormal alanine aminotransferase was present, significant differences between macrophage inflammatory protein 2 and T-cell immunoglobulin domain and mucin-domain-containing molecule-3 levels between patients with mild, moderate, severe chronic hepatitis B or fulminant hepatitis B were observed (P < 0.05). Our results suggest that T-cell immunoglobulin domain and mucin-domain-containing molecule-3 and macrophage inflammatory protein 2 could serve as alanine aminotransferase, direct bilirubin or total bilirubin complementary indices for determining the status of patients with hepatitis B.

Self-frequency-doubled BaTeMo2O9 Raman laser emitting at 589 nm.

In this paper, the spontaneous Raman spectra and second harmonic generation (SHG) properties at 589 nm of a novel Raman crystal BaTeMo(2)O(9) (BTM) were investigated. The BTM crystal was cut along the type-II SHG phase-matching direction for the first-order Raman shift at 1178 nm to realize the SRS and SHG simultaneously. Pumped by a nanosecond 1064 nm laser source, a self-frequency-doubled BTM Raman laser operating at 589 nm has been demonstrated for the first time. At the pump pulse energy of 48 mJ, the maximum yellow laser output pulse energy of 5.6 mJ was obtained with an optical-to-optical conversion efficiency of 11.7%. Our results show that BTM crystal is one of the promising candidate Raman materials to generate yellow laser radiation.

Diode-pumped continuous wave tunable and graphene Q-switched Tm:LSO lasers.

We have investigated the lasing characteristics of Tm:LSO crystal in three operation regimes: continuous wave (CW), wavelength tunable and passive Q-switching based on graphene. In CW regime, a maximum output power of 0.65 W at 2054.9 nm with a slope efficiency of 21% was achieved. With a quartz plate, a broad wavelength tunable range of 145 nm was obtained, corresponding to a FWHM of 100 nm. By using a graphene saturable absorber mirror, the passively Q-switched Tm:LSO laser produced pulses with duration of 7.8 µs at 2030.8 nm under a repetition rate of 7.6 kHz, corresponding to pulse energy of 14.0 µJ.

Inhibition effect produced by dominant negative mutant fusion protein PreS2-TLM-ScFv-HBcDN on HBV replication in vitro.

A mammalian expression vector comprised of the PreS2-TLM (translocation motif), a single-chain variable fragment (ScFv) that binds to hepatitis B surface antigen (HBsAg) and the EGFP gene was constructed. A stably transformed cell line that could express and secrete the fusion protein (PreS2-TLM-ScFv-EGFP) was established. HBsAg-positive HepG2.2.15 cells and HepG2 and HeLa cells were incubated with the supernatant of the transformed cell line cultures for evaluating the cellular permeability of PreS2-TLM-ScFv-EGFP. The location of the fusion protein PreS2-TLM-ScFv-EGFP in HepG2.2.15 cells was observed with immunofluorescence staining. EGFP was next replaced by a dominant negative mutant of the hepatitis B virus core gene (HBcDN) for producing fusion protein PreS2-TLM-ScFv-HBcDN, which was detected by western blot. The supernatant containing fusion protein PreS2-TLM-ScFv-HBcDN was added to the cultures of HepG2.2.15 cells, and the packaged hepatitis B virus (HBV) pregenomic RNA expression levels in the cells were measured using qRT-PCR. The results of the in vitro study indicated that the packaged HBV pregenomic RNA expression levels in HepG2.2.15 cells significantly decreased when these cells were exposed to the supernatant at the dose of 25% for 24, 48 and 72 h, or at the dose of 12.5% for 72 h.

Passively Q-switched Nd:Sc0.2Y0.8SiO5 dual-wavelength laser with the orthogonally polarized output.

We have demonstrated a laser-diode pumped continuous-wave (CW) and passively Q-switched laser with a Nd:Sc(0.2)Y(0.8)SiO(5) (Nd:SYSO) crystal for the first time. In the CW operation, the laser was found to oscillate in tri-wavelength regime at 1074.8 nm, 1076.6 nm and 1078.2 nm, respectively. The maximum CW output power of 1.96 W was obtained, giving an optical-to-optical conversion efficiency of 35% and a slope efficiency of 39%. Using either Cr(4+):YAG or V(3+):YAG crystal as saturable absorber, stable passively Q-switched laser was obtained at dual-wavelength of 1074.8 nm and 1078.2 nm with orthogonal-polarization. The maximum average output power, pulse repetition rate, and shortest pulse width were 1.03 W, 50 kHz, and 24 ns, respectively. The passively Q-switched dual-wavelength laser could be potentially used as a source for generation of terahertz radiation.

Expression of DNA methyltransferases in the mouse uterus during early pregnancy and susceptibility to dietary folate deficiency.

We have characterized the uterine expression of DNA methyltransferases (DNMTs) during early pregnancy in mice and determined whether a folate-deficient diet (FDD) can affect DNMTs in this context. Within endometrial cells, expressions of DNMT (cytosine-5) 1 (Dnmt1), Dnmt3a, and Dnmt3b were significantly elevated during the prereceptive phase of pregnancy but generally returned to baseline levels during receptive and postimplantation periods. As such, the transcription of DNMT genes is temporally regulated during early pregnancy. When comparisons were made between implantation sites (IS) and inter-IS on day 5 of pregnancy, lower levels of Dnmt3a were detected at IS. Comparisons between IS and inter-IS did not reveal significant expression differences for other DNMT genes. When tissue sections were examined, DNMT3A was specifically lower in the stroma of IS. Reduced DNMT1 and DNMT3B levels were also observed in the luminal and glandular epithelia of IS, whereas no obvious differences in the stroma were detected. In pseudo-pregnant mice subjected to a FDD, levels of Dnmt1 and Dnmt3a (but not Dnmt3b) were significantly upregulated in endometrial tissues, as compared with controls. When tissues from these folate-deficient mice were examined, DNMT1 levels were elevated in both the luminal and glandular epithelia, whereas DNMT3A was upregulated in the luminal epithelium and the stroma. A slight increase in DNMT3B levels was detected in the glandular epithelium. These results indicate that DNMTs may regulate the transcription of endometrial genes associated with embryo implantation and that levels of DNMTs are affected by dietary folate in mice.

[Genetic diversity of Sparganum isolates from snakes in Hunan Province based on mitochondrial nad4 and nad5 genes].

OBJECTIVE: To investigate the genetic diversity and phylogenetic relationship of Sparganum isolates from snakes in Hunan Province. METHODS: The partial mitochondrial NADH dehydrogenase subunit 4 (pnad4) and NADH dehydrogenase subunit 5 (pnad5) genes were amplified using a PCR assay in 7 Sparganum isolates from snakes in Hunan Province and the amplification product was sequenced. The homology and genetic evolution were investigated using the software DNAMAN 7.0, MegAlign, DnaSP 5.0 and MEGA 5.0. RESULTS: The pnad4 and pnad5 gene sequences were approximately 578 bp and 484 bp in length in the 7 Sparganum isolates from Hunan Province, and the percentages of genetic variations were 0 to 2.8% and 0 to 0.8%, respectively. There were 4 haplotypes detected in both the pnad4 and pnad5 genes, with global haplotype diversities of 0.810 ± 0.016 and 0.905 ± 0.011, nucleotide diversities of 0.006 ± 0.005 and 0.004 ± 0.003, and mean nucleotide variations of 3.960 and 1.905, respectively. Phylogenetic analysis showed that all 7 Sparganum isolates from snakes in Hunan Province were clustered into the same branch with Spirometra erinaceieuropaei isolates from different regions/hosts in the world, which belonged to S. erinaceieuropaei, which were close to Diphyllobothrium latum and far from other tapeworms. CONCLUSIONS: There is a low genetic variation in snake-derived S. erinaceieuropaei isolates from Hunan Province, and both pnad4 and pnad5 genes may be potential molecular genetic markers for identification of S. erinaceieuropaei.

Comparative study on the intracavity frequency-doubling 532 nm laser based on gray-tracking-resistant KTP and conventional KTP.

A comparative study of a frequency-doubling 532 nm laser based on gray-tracking-resistant KTP (GTR-KTP) and conventional KTP is presented. The intracavity GTR-KTP was proved to have better temperature characteristics than that of conventional KTP. Within the normalized output power variation range of 0.8-1.0, GTR-KTP has a temperature tolerance of 35 degrees C, broader than the 21 degrees C obtained with conventional KTP. Under the laser diode (LD) pump power of 180 W, the maximum average output power at 532 nm was 40.6 W for GTR-KTP at a repetition frequency of 10 kHz. In the case of conventional KTP, the maximum available LD pump power was limited to 150 W, with the corresponding maximum green average output power of 27.2 W.

Note: Self-biased voltage to suppress secondary electrons by a ZnO varistor in a compact pulsed neutron generator.

A large amount of back streaming electrons will bring about a part of current drain on power supply, cause sparking or high-voltage breakdowns, and affect the neutron yield and waveform for a compact sealed-tube pulsed neutron generator. A novel idea which uses a ZnO varistor to provide a constant self-biased voltage to suppress the secondary electrons is introduced. The I-V curve for the ZnO varistor was measured in the experiment. The effects of suppressing the secondary electrons were investigated using a ZnO varistor, linear resistors, and an independent power supply, respectively. The results show that the secondary electrons are suppressed effectively by the compact ZnO varistor, while not increasing the size and the component of the device. It is a promising design for compact sealed-tube neutron generators.