Abstract: Objective　To investigate the pollution of paralytic shellfish poisons (PSP) in shellfish sold in Hainan Province from 2018 to 2021. Methods　From 2018 to 2021, the content of 10 paralytic shellfish poisons including saxitoxin (STX), neosaxitoxin (neoSTX), gonyautoxins 1 (GTX1), gonyautoxins 2 (GTX2), gonyautoxins 3 (GTX3), gonyautoxins 4 (GTX4), gonyautoxins 5 (GTX5), decarbamoylsaxitoxin (dcSTX), decarbamoylgonyau toxins 2 (dcGTX2) and decarbamoylgonyau toxins 3 (dcGTX3) in 7 kinds of shellfish commonly sold in 13 cities and counties in Hainan province was analyzed. Results　The detection rate of PSP in 360 shellfish samples was 10.3%. Among them, the highest detection rate of STX was 5.83%, followed by GTX2 detection rate of 4.17%; the detection rate of neoSTX and GTX3 were both 1.67%; the detection rate of GTX1 was 1.39%. None of the five PSP, GTX4, GTX5, dcSTX, dcGTX2 and dcGTX3, were detected. Four types of PSP were detected in fanscallops, two were detected in oysters, mussels and Scapharca subcrenata, only one was detected in scallops, and no toxin contamination was detected in clams and razor clams. A single sample of fanscallops detected a maximum of 4 PSP, and a single sample of oysters, scallops, mussels and Scapharca subcrenata detected a maximum of 1 PSP. The equivalence of PSP in all samples was ND-155.6 μg/kg.The annual detection rate of PSP from high to low was: 20.0% in 2020, 15.6% in 2019, 5.3% in 2018, and 2.0% in 2021, and none of the samples tested exceeded the standard. Continuously detectable STX in 2018-2020, all PSP that could be detected in 2018 were STX. In 2019, in addition to STX detected in scallops and Scapharca subcrenata, neoSTX was also detected in oysters, mussels and Scapharca subcrenata. In 2020, PSP was only detected from scallops, and GTX2 could be detected in all positive specimens, while 5 STX, 5 GTX1 and 6 GTX3 were detected. Only GTX2 detected from scallops in 2021. STX was detected in shellfish sold in 12 cities and counties, GTX2 can be detected in 10 cities and counties, neoSTX can be detected in 5 cities and counties, GTX1 and GTX2 were detected in 4 cities and counties respectively. Shellfish sold in Wenchang and Lingshui markets can detect 5 types of PSP. Conclusion　Some types of shellfish on the market in Hainan are contaminated with some kind of PSP pollution risks, and it is necessary to strengthen the supervision of PSP in marketed shellfish.

OBJECTIVE: To explore the growing development and community succession of main sarcosaphagous insects on pig carcasses in summer indoor and outdoor environment in Shenzhen area and to estimate the postmortem interval (PMI). METHODS: From early May to August in 2013, in Forensic Medical Examination Center of Shenzhen Public Security Bureau, the main insect species and the decomposition process were observed in two adult pig carcasses of simulative indoor and outdoor environment. The different decomposition stages and the community succession of insects were recorded. RESULTS: The indoor and outdoor pig carcasses showed skeleton 412.5 and 325 hours after death, respectively. The main species of flies on pig carcasses were Chrysomya megacephala, Chrysomya rufifacies and Chrysomya chani. The main species of beetles were Crecphilus maxillosus, Necrobia ruficollis, Saprinus splendens and Dermestes maculatu. The dominant species of flies in the outdoor pig carcasses obviously produced the second generations due to the effect of mass rainfall, nor in the indoor pig carcasses. CONCLUSION There are regular patterns on the community succession of insects on pig carcasses in summer indoor and outdoor environment in Shenzhen area. The activity patterns of seven typical insects and their larva show important value for estimating PMI.
Animals ; Autopsy ; Cadaver ; China ; Coleoptera ; Death ; Diptera ; Environment ; Insecta/growth & development* ; Larva ; Population Dynamics ; Postmortem Changes ; Seasons ; Swine

ObjectiveTo investigate the feasibility and importance of the application of simulation ward in medical practice between classes.MethodsTo divide the interns into two groups:the experimental group of 30 and the control group of 30. Both groups apply the simulation ward to practice between classes and both are assessed at the end of the practice.ResultsTo compare the final score of the experimental group and the control group,and significant differences are found in the following aspects:humanistic care,history taking,physical examination,medical record analysis,the theoretical knowledge examinations with the data of P ＜0.05.ConclusionThe application of simulation ward in medical practice between classes can improve the quality of clinical teaching.

A method was developed for the determination of eight steroid hormones ( estrone, α/β-estradiol, estriol, testosterone, epitestosterone, progesterone and testosterone propionate ) in butter samples by gel permeation chromatography ( GPC) purification-followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The samples were first extracted by ethylacetate/cyclohexane (1:1, V/V) and the extract was later degreased by GPC column. Then, the GPC concentrate was separated using a C18 column ( 100 mm í2. 0 mm i. d. , 3. 0 μm) with gradient elution of acetonitrile/water. Finally, the steroid hormone components were qualitatively and quantitatively determined by mass spectrometer with electrospray ionization in multi reaction monitoring mode. Using matrix matched external standard method, good linearity in response could be obtained in the concentration range of 1 . 0-20 . 0 μg/kg with correlation co-efficiency larger than 0 . 999 . The detection limits of the method were 0. 04-0. 30 μg/kg and the quantification limit was 1. 0 μg/kg. At the spike levels of 1. 0, 2. 0 and 4. 0μg/kg, the recoveries of hormones were within the range of 64. 1%-110%, and the relative standard deviation ( RSD) was less than 11%. The results show that the method is accurate and reliable, and meets the requirements for determination of 8 steroid hormones in butter samples.

AIMTo observe the effects of Ca2+ -activated K+ channel of primary cultured fetal SD rat cortex neurons in the veratridine triggered neuronal damage.

METHODSThe patch clamp technique of cell-attach and inside-out mode for these two kinds of single channel recordings were used.

RESULTSExtracellular veratridine activated the Kca. In Ca2+ bath solution of cell-attach mode, Vp + 30 mV, when the concentration (micromol/L) of veratridine were 15,25,50 and 75, the open probabilities of the channel were 0.014 +/- 0.003, 0.085 +/- 0.010, 0.132 +/- 0.016 and 0.059 +/- 0.006 (P < 0.01) respectively. It appeared concentration-dependent within 50 micromol/L veratridine. In Ca2+ free bath solution of cell-attach mode, Vp = +50 mV, when the concentration (micromol/L) of veratridine were 15, 40,60 and 100, the open probabilities of the channel were 0.014 +/- 0.010, 0.113 +/- 0.006, 0.141 +/- 0.004 and 0.295 +/- 0.009 (P < 0.05) respectively. In the 6 cases of inside-out mode patch clamp, Vp = +40 mV, when the concentration of veratridine were 0, 25 micromol/L and 50 micromol/L, the open probabilities of the channel were 0.011 +/- 0.008, 0.010 +/- 0.010 and 0.012 +/- 0.007 (P > 0.05) respectively. There were no significant difference on open probabilities, average open/close times and amplitudes at different intracellular veratridine concentration.

CONCLUSIONVeratridine can affect the activation of the Kca channel through regulating the concentration of cytoplasmic free Ca2+. The opening of Kca activated by increase of intracellular Ca2+ during the early stage of anoxia may be a protection reaction of ischemic neurons.

Animals ; Animals, Newborn ; Calcium ; metabolism ; Cells, Cultured ; Neurons ; cytology ; drug effects ; physiology ; Patch-Clamp Techniques ; Potassium Channels, Calcium-Activated ; metabolism ; Rats ; Rats, Sprague-Dawley ; Veratridine ; pharmacology

OBJECTIVETo introduce a novel digital surgery technique based on partial reconstruction of skull and its application in tumor resection and on-sport reconstruction surgery.

METHODSThe partial 3d reconstruction according to CT scanning data was obtained to get 3d model of both tumor and normal skull, then to define the resection area on tumor data through people-computer interaction process, do reconstruction the simulation on the remained model, pre-fabricate the cutting template and custom the implant. The resection template to confirm the message in surgery simulation can be transferred to real surgery accurately.

RESULTSAll the four cases by using this method showed great consistency of the real and simulated surgery and got a good appearance of reconstruction.

CONCLUSIONSThe surgery simulation technique based on partial 3d reconstruction has great assistance to tumor resection and one-stage reconstruction surgery.

Adult ; Female ; Head and Neck Neoplasms ; surgery ; Humans ; Imaging, Three-Dimensional ; Male ; Middle Aged ; Reconstructive Surgical Procedures ; methods ; Surgery, Computer-Assisted ; methods ; Young Adult

In the past few decades, our understanding of platelets has made great progress. Platelets play an unexpected central role in cancer and greatly affect the behavior of cancer cells. At the same time, the physiology and phenotype of platelets are also affected by cancer cells. Therefore, platelet-based tumor targeted therapy strategies have attracted the attention of researchers, but the limitations of their application require more attention. In this paper, the strategies of platelet-based tumor targeted therapy are summarized, and the strategies of platelet mimicking nanocarrier delivery, platelet hitch riding, platelet membrane coating biomimetic and engineered platelet targeting are mainly introduced. The easy activation, hard storage and unknown functional and phenotypic changes of platelets were discussed. At the same time, the strategy of platelet-based targeted tumor therapy is reviewed from theoretical basis and practical application. The development potential of platelets in the field of tumor diagnosis and treatment is discussed, which will provide some theoretical reference for the study of platelet-related tumor diagnosis and targeted therapy.

A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the determination of butoconazole in human plasma. Human plasma samples of 0.2 μL were pretreated by a single step protein precipitation procedure and analyzed using a high performance liquid chromatography (HPLC) electrospray tandem mass spectrometer system. The compounds were eluted isocratically on an Inertsil ODS-SP column (100 mm×2.1 mm, 3 μm), ionized using a positive ion atmospheric pressure electrospray ionization source and analyzed using multiple reaction monitoring (MRM) mode. The ion transitions monitored were m/z 412.8→165.1 for butoconazole and m/z 453.4→230.3 for the internal standard. The chromatographic run time was 3.5 min per injection, with retention time of 2.47 min and 2.15 min for butoconazole and repaglinide, respectively. The method was validated to be linear over the range of 20 to 8000 pg/mL (r>0.999) by using a weighted (1/x(2)) quadratic regression. The mean recovery rate was more than 86.7%, and the intra- and inter-day precision of the quality control samples (QCs) was less than 8.3% and the accuracy ranged from 96.0% to 110.2%, which indicated that the quantitative method was reliable and accurate. The method is simple, rapid, and has been applied successfully to a pharmacokinetics study of butoconazole nitrate suppositories in healthy Chinese females.

OBJECTIVETo explore the mechanism of Shangke Jiegu Tablet (SJT)in repairing the mandibular defect.

METHODSTotally 72 healthy male New Zealand rabbits were randomly divided into the normal control group (n = 24), the model group (n = 24), and the SJT group (n = 24). Then the mandibular defect model was established. Animals in the normal control group and the model group were fed with normal forage, while those in the SJT group were fed with SJT forage. On the day 7, 14, 28, and 56 after model establishment, 6 rabbits were killed in each group. The bone was collected from the mandibular defect. The gene expressions of osteoprotegerin (OPG) and osteoprotegerin ligand (OPGL) were detected by means of RT-PCR. The positive dyeing strength and area of the bone tissue were detected by means of immunohistochemical technique.

RESULTSCompared with the normal control group, the degree of OPGmRNA expression was remarkably up-regulated on day 7 after model establishment (P < 0.05) and the degree of OPGLmRNA expression was remarkably up-regulated on day 14 after model establishment (P < 0.05) in the model group. Compared with the model group, the degree of OPGmRNA expression was remarkably up-regulated (P < 0.05), and the positive dyeing strength and area of bone tissue were stronger and broader on day 14, 28, and 56 after model establishment in the SJT group. The degree of OPGLmRNA expression was remarkably down-regulated (P < 0.05), and the positive dyeing strength and area of bone tissue were weaker and smaller on day 14 after model establishment in the SJT group. The ratio of OPGmRNA/OPGLmRNA was remarkably up-regulated on day 14, 28, and 56 after model establishment (P < 0.05).

CONCLUSIONThe effect mechanism of promoting mandibular defect repairing by SJT may be correlated to regulating the expressions of OPGmRNA and OPGLmRNA.

Animals ; Drugs, Chinese Herbal ; pharmacology ; Gene Expression ; drug effects ; Ligands ; Male ; Mandibular Injuries ; genetics ; metabolism ; Osteoprotegerin ; metabolism ; RANK Ligand ; metabolism ; Rabbits ; Wound Healing ; drug effects

OBJECTIVETo evaluate the impact of neoadjuvant chemoradiation on perineal wound healing following abdominoperineal resection(APR) for lower rectal cancer.

METHODSData of 93 patients who underwent APR for low rectal cancer between January 2005 and January 2009 in Peking Union Medical College Hospital were reviewed, including patients who received neoadjuvant chemoradiation (n=29) and those undergoing surgery alone(n=64). Perineal wound healing was the primary outcome measurement. Condition of wound healing was classified as good, moderate, and poor and was compared between the two groups.

RESULTSTwenty nine patients in the neoadjuvant group received preoperative regional radiation(50 Gy, 25 fractions/5 weeks) with synchronous FOLFOX4 chemotherapy(fluorouracil and oxaliplatin). In the neoadjuvant group, wound healing after APR was good in 18 patients(62.1%), moderate in 6(20.7%), and poor in 5(17.2%). In patients who had surgery alone, wound healing after APR was good in 41 patients(64.1%), moderate in 15(23.4%), and poor in 8(12.5%). There was no significant difference in the incidence of wound infection(poor wound healing)between the two groups(P=0.773).

CONCLUSIONNeoadjuvant chemoradiation therapy is not associated with increased perineal wound infection following abdominoperineal resection for low rectal cancer.

Aged ; Combined Modality Therapy ; Female ; Humans ; Male ; Middle Aged ; Neoadjuvant Therapy ; Perineum ; surgery ; Rectal Neoplasms ; surgery ; therapy ; Rectum ; surgery ; Wound Healing