[Risk assessment for thyroid (131)I exposure among nuclear medical staff].

Objective: To explore the main risk factors and to assess the risk of thyroid (131)I exposure among nuclear medical workers. Methods: From March to October in 2019, cluster sampling was adopted to collect the number of (131)I automatic packer and patients treated for thyroid cancer, hyperthyroidism and liven cancer used (131)I, the practicing categories, job rotation and (131)I operation condition of nuclear medical staff were also investegated in the 21 nuclear medicine hospitals in Fujian Province that carried out (131)I nuclide diagnosis and treatment in 2018. (131)I aerosol and personnel thyroid (131)I were measured in 20 hospitals using (131)I for thyroid cancer or hyperthyroidism. The main risk factors leading to thyroid (131)I exposure of nuclear medical staff were found and aninternal exposure risk assessment model was established. Results: The detection rate of (131)I aerosol and personnel thyroid (131)I were 80.0% (16/20) and 25.5% (62/243) in 20 hospitals. The situation of packaging and administration about (131)I in the nearly 10 effective half-life, the concentration of (131)I aerosol in the nuclear medicine workplace, the number of patients treated with (131)I for thyroid cancer or hyperthyroidism were the main risk factors leading to thyroid (131)I internal exposure (OR=5.857, 6.808, 1.983, 1.150, P<0.05) . Conclusion: (131)I exposure is common among nuclear medical workers, attention should be paid to the protection of internal radiation, strengthen the control of main risk factors, so as to reduce the risk of internal radiation.

[Percutaneous full-endoscopic removalof lumbar dumbbell tumors viatransforaminal approach].

Objective: To investigate the novel application and effectof Percutaneous Full-Endoscopic transforaminal approach for lumbar dumbbell tumors. Methods: A retrospective analysis of 12 cases of lumbar dumbbell tumors was conducted by Percutaneous full-endoscopic transforaminal approach in the Department of Neurosurgery, Fujian Medical University Union Hospital from Feb, 2018 to Jul, 2019. According to Eden classification, 5 cases in type Ⅲ and 7 cases in type Ⅳ. The Japanese Orthopaedic Association (JOA) score and Pain Visual analogue Scale (VAS) were used to compare the recovery of neurological function before and after surgery. Results: All the 12 tumors were completely removed in one stage. The pathological reports were all schwannomas (WHO grade Ⅰ). The VAS scores were significantly decreased compared with preoperative ones (P<0.001). The JOA scores were significantly improved without obvious complications and spinal instability. Median length of follow-up was 14 months with a range of 4 months to 20 months, there is no tumor recurrence and spinal instability. Conclusion: In the treatment of lumbar dumbbell spinal tumor, the full endoscopic transforaminal approach is a novel, safe and effective surgical procedure which removes the tumors intra-foramen and extra-foramen with less damage of spine, smaller possibility of instability and faster recovery.

Radio frequency measurement and tuning of a 13 MeV Alvarez-type drift tube linac for a compact pulsed hadron source.

This paper describes the radio frequency (RF) measurement and tuning result of a 13 MeV Alvarez-type drift tube linac (DTL) for a compact pulsed hadron source (CPHS) at Tsinghua University. The design, machining, assembly, and alignment of the DTL are presented for integrity. The CPHS project consists of a high-current proton linac (13 MeV, 16 kW, peak current of 50 mA, 0.5 ms pulse width at 50 Hz), a neutron target station, a small-angle neutron scattering instrument, and a neutron imaging/radiology station. The linac contains an electron cyclotron resonance ion source, a low energy beam transport line, a four-vane radio frequency quadrupole (RFQ) accelerator, an Alvarez-type DTL, a high energy beam transport line, and a RF power supply and distributor. Construction on the CPHS started in June 2009, and the CPHS has provided 2000 h since 2013 to users with the neutrons produced by the 3 MeV proton beam from the radio frequency quadrupole bombarding on the beryllium target as an achievement of its mid-term objective. Presently, the tuning of the assembled DTL cavity has been completed successfully. The 4.3-m-long DTL consists of 40 accelerating cells, among which 39 full-length drift tubes (DTs) are suspended inside the cavity, and two half-length DTs are mounted inside the two end flanges of the cavity. Each DT contains a permanent magnet quadrupole. Thirteen post couplers and nine tuners are available for the tuning of the field. The relative error of the field after tuning is within ±1.6%, with a tilt sensitivity within ±33%/MHz in all cells. The beam energy will reach its designed value of 13 MeV after the DTL is installed in the beam line downstream the 3 MeV RFQ accelerator.

[Application of dysphonia severity index in laryngeal reflux related voice diseases].

Objective:To discuss the validity and reliability of dysphonia severity index in evaluating the effect of diagnosis and treatment of laryngeal reflux related voice diseases. Method:54 cases of voice disease patients accompanied by laryngopharyngeal reflux from January 2016 to June 2017 in department of otorhinolaryngology of our hospital were divided into two groups according to treatment type. 32 cases in the operation group received laser surgery and standard acid suppression therapy for 6 weeks, and 22 patients in the non-operation group received standard acid suppression therapy for 6 weeks. 24 h multichannel impedance pH (MCII-pH) monitoring was carried out. The indexes of reflux symptom, reflux finding score, subjective auditory perception and objective acoustic parameters of voice were measured before and after treatment, and the dysphonia severity index was calculated and analyzed. Result:There was no significant difference in age, sex and course of disease between the two groups (P> 0.05).Compared with pre-treatment, RSI, RFS, Jitter, Shimmer, G and R in two groups decreased significantly after treatment, and MPT, DSI increased significantly (P<0.05). Before treatment, RSI, RFS, Jitter, Shimmer, G and R in the operation group were significantly higher than those in the non-operation group, and MPT, DSI were lower (P<0.05). There were no significant differences in the parameters between the two groups after treatment (P> 0.05). DSI was negatively correlated with GRBAS scoring parameters, Jitter and Shimmer, and positively correlated with RSI, RFS, and MPT (P<0.01). DSI is related to the location of the lesion (P<0.05) The incidence of anxiety was 27.27% in patients with moderate and severe sudden sensorineural hearing loss, and the incidence of depression was 25.25%. The scores of anxiety and depression were statistically significant (P<0.05). The multivariate logistic regression analysis showed that the status of anxiety and depression was accompanied by symptoms and other diseases (P<0.05). There was a significant difference between the effective group, the significant efficacy group and the cured group (P<0.05). The difference between the scores before and after treatment was compared. Differences in the ineffective group compared with the other three groups, and the cured group compared with the other three groups of anxiety, depression were statistically significant. Conclusion:DSI can be used as an objective evaluation index for the diagnosis and treatment of laryngeal reflux related voice diseases, and it is accurate and reliable.

Strontium ranelate increases cartilage matrix formation.

Based on previous studies showing that strontium ranelate (S12911) modulates bone loss in osteoporosis, it could be hypothesized that this drug also is effective on cartilage degradation in osteoarthritis (OA). This was investigated in vitro on normal and OA human chondrocytes treated or not treated with interleukin-1beta (IL-1beta). This model mimics, in vitro, the imbalance between chondroformation and chondroresorption processes observed in vivo in OA cartilage. Chondrocytes were isolated from cartilage by enzymatic digestion and cultured for 24-72 h with 10(-4)-10(-3) M strontium ranelate, 10(-3) M calcium ranelate, or 2 x 10(-3) M SrCl2 with or without IL-1beta or insulin-like growth factor I (IGF-I). Stromelysin activity and stromelysin quantitation were assayed by spectrofluorometry and enzyme amplified sensitivity immunoassay (EASIA), respectively. Proteoglycans (PG) were quantified using a radioimmunoassay. Newly synthesized glycosaminoglycans (GAGs) were quantified by labeled sulfate (Na2(35)SO4) incorporation. This method allowed the PG size after exclusion chromatography to be determined. Strontium ranelate, calcium ranelate, and SrCl2 did not modify stromelysin synthesis even in the presence of IL-1beta. Calcium ranelate induced stromelysin activation whereas strontium compounds were ineffective. Strontium ranelate and SrCl2 both strongly stimulated PG production suggesting an ionic effect of strontium independent of the organic moiety. Moreover, 10(-3) M strontium ranelate increased the stimulatory effect of IGF-I (10(-9) M) on PG synthesis but did not reverse the inhibitory effect of IL-1beta. Strontium ranelate strongly stimulates human cartilage matrix formation in vitro by a direct ionic effect without stimulating the chondroresorption processes. This finding provides a preclinical basis for in vivo testing of strontium ranelate in OA.

Irreversible chronic vascular rejection occurs only after development of advanced allograft vasculopathy: a comparative study of a rat cardiac allograft model using a retransplantation protocol.

Indefinitely surviving WF.1L (RT1(1)) cardiac allografts transplanted to LEW (RT1(1)) recipients provide an ideal model for controlled comparative studies of chronic vascular rejection (CVR). To determine the stage of development at which the progressive CVR can be reversed when deprived of an ongoing recipient alloimmune response, WF.1L-LEW cardiac allografts were retransplanted back into syngeneic donor strain WF.1L recipients at specific time periods after initial allogeneic engraftment and were maintained in WF.1L syngeneic hosts for a further 40 days. The vascular changes in the retransplanted allografts were compared with those of nonretransplanted allografts and with nonretransplanted and retransplanted LEW-LEW isografts examined at similar time periods. The early vasculopathic inflammatory changes were consistently reversed by retransplantation of the cardiac allografts back into syngeneic recipients after 20 days and 40 days of allotransplantation. Syngeneic retransplantation of the cardiac allografts at 60 days after allotransplantation did not reverse the essentially nonvasculitic occlusive vasculopathy invariably present in WF.1L-LEW cardiac allografts at this time period. Thus, the vasculitic and minimal subocclusive myointimal changes associated with early CVR in this model are alloantigen dependent and reversible. Irreversible CVR occurs only after advanced proliferative vasculopathy has been established in the allogeneic host.

Evidence that recipient CD8+ T cell depletion does not alter development of chronic vascular rejection in a rat heart allograft model.

Progressive chronic vascular rejection is a central feature of indefinitely surviving WF.1L LEW/Gut (RT1(1)) heart grafts transplanted to LEW (RT1(1)) recipients in unmodified donor-recipient combinations. At 70 days posttransplantation, large vessels of the grafts are characterized by the presence of vasculitis, vasculitis with associated variable myointimal thickening, and occlusive myointimal thickening with minimal or absent concomitant vasculitis. To assess the potential role of CD8+ T cells as critical effectors of chronic vascular rejection in this model, LEW recipients of WF.1L heart grafts were effectively depleted of CD8+ T cells as a result of prior thymectomy and anti-CD8 (MRC OX8) monoclonal antibody administration prior to transplantation. WF.1L heart grafts transplanted to LEW recipients that had undergone prior sham thymectomy and MRC OX8 administration, or thymectomy and administration of antibody-free culture supernatant, provided appropriate controls. At 70 days posttransplantation, large vessels of WF.1L heart grafts in all 3 transplantation groups showed similar morphologic features, which were comparable to those observed in heart grafts of long-surviving unmodified donor-recipient pairs. This study has shown that profound selective depression of recipient CD8+ T cells does not alter the characteristic features of chronic vascular rejection in this rat cardiac model, and provides evidence that CD8+ T cells play no critical role in the initiation or development of progressive vascular damage in this setting.

Functionally graded calcium phosphate coatings produced by ion beam sputtering/mixing deposition.

Ar+ ion beam sputtering/mixing deposition was used to produce thin calcium phosphate coatings on titanium substrate from hydroxyl-poly-calcium sodium phosphate (HPPA) and HPPA + Ti targets. Three types of coatings (one type of monolayer coating and two types of functionally graded coating) were manufactured. It was found that as-sputtered coatings were amorphous. No distinct hydroxyl band was observed in the FTIR spectra, but new absorption bands were determined for CO3(2-), which resulted during the deposition process. Compositional gradients from the surface to the interior (i.e. adjacent to the substrate) were achieved for the functionally graded coatings. Post-deposition heat treatment indicated that the bonding strength between the coating and the substrate was improved by the use of functionally graded structures.

In vitro study of the antioxidant properties of non steroidal anti-inflammatory drugs by chemiluminescence and electron spin resonance (ESR).

OBJECTIVES: To determine the antioxidant activities of nonsteroidal anti-inflammatory drugs (NSAIDS), we examined by chemiluminescence (CL) and electron spin resonance (ESR) their scavenging properties towards lipid peroxides, hypochlorous acid and peroxynitrite. METHODS: The antioxidant properties of nimesulide (NIM), 4-hydroxynimesulide (4-HONIM), aceclofenac (ACLO), 4-hydroxyaceclofenac (4-HOA-CLO), diclofenac (DICLO) and indomethacin (INDO) were tested on four different reactive oxygen species (ROS) generating systems: (I) phorbol-myristate acetate (PMA)-activated neutrophils, (II) Fe2+/ascorbate-induced lipid peroxidation, (III) HOCl-induced light emission, (IV) the kinetics of ONOO- decomposition followed by spectrophotometry. ROS production was monitored by luminol-enhanced CL or by ESR using two different spin traps. RESULTS: At 10 microM, ACLO, NIM, 4-HONIM, 4-HOA-CLO, and DICLO decreased luminol-enhanced CL generated by PMA-activated neutrophils. Inversely, INDO increased the luminol enhanced CL. Interestingly, hydroxylated metabolites were more potent antioxidants than the parent drugs. Furthermore, all drugs tested, excepted ACLO, lowered lipid peroxidation induced by Fe2+/ascorbate system. ACLO and DICLO, even at the highest concentration tested (100 microM), did not significantly lower HOCl induced CL, whereas the other drugs were potent scavengers. Finally, all the NSAIDS accelerated decomposition of ONOO-, suggesting a potential capacity of the molecules to scavenge peroxynitrite. CONCLUSION: The NSAIDs possess variable degrees of antioxidant activities, linked to their ability to react with HOCl, lipid peroxides or ONOO-. These antioxidant activities could offer interesting targeted side-effects in the treatment of joint inflammatory diseases.

Effects of nimesulide and sodium diclofenac on interleukin-6, interleukin-8, proteoglycans and prostaglandin E2 production by human articular chondrocytes in vitro.

OBJECTIVES: The aim of this study was to investigate the effects of two nonsteroidal anti-inflammatory drugs (NSAIDs), nimesulide and sodium diclofenac, on the production of proteoglycans (PG), prostaglandin E2 (PGE2) and cytokines (IL-6 and IL-8) by human articular chondrocytes in vitro. METHODS: Enzymatically isolated chondrocytes were cultured under constant agitation in a well defined culture medium. Specific radioimmunoassays were used to quantify PG and PGE2 production. Cytokine production (IL-6 and IL-8) was assayed by enzyme amplified sensitivity immunoassays (EASIAs). RESULTS: At a concentration of 3 micrograms/ml, nimesulide did not affect the PG production by chondrocytes. This concentration was superior to the highest level of nimesulide found in the synovial fluid of patients with rheumatoid arthritis 3 hours after the last oral administration of nimesulide (100 mg twice daily for 7 days). At 6 micrograms/ml a significant reduction in the PG content was obtained in the cellular phase in 5 out of the 8 cultures investigated. No similar effect was observed in the culture supernatants. Above this concentration nimesulide inhibited PG production in a dose-dependent manner. At concentrations ranging from 0.005 to 1 microgram/ml diclofenac did not significantly alter PG production. At therapeutic concentrations PGE2 production was totally inhibited by nimesulide, thus suggesting that PG inhibition is not linked to PGE2 production. Nimesulide inhibited PGE2 production by unstimulated (IC50 = 6 ng/ml) and IL-1 beta-stimulated (IC50 = 6.9 ng/ml) chondrocytes. At these concentrations, PGE2 production was fully inhibited by diclofenac. Furthermore, both nimesulide and diclofenac at therapeutic concentrations significantly decreased spontaneous and IL-1 beta-stimulated IL-6 production by human chondrocytes, but did not modify IL-8 production. CONCLUSION: From the results of this study we conclude that nimesulide and diclofenac at therapeutic concentrations are potent inhibitors of PGE2 and IL-6 production while they do not modify proteoglycan or IL-8 production.

Increase in cytokine production (IL-1 beta, IL-6, TNF-alpha but not IFN-gamma, GM-CSF or LIF) by stimulated whole blood cells in postmenopausal osteoporosis.

Postmenopausal osteoporosis is a progressive disorder characterized by a decreased bone mass and increased susceptibility to fractures. Several investigations have suggested that one of the mechanisms through which estrogen prevents bone loss was a modulation on secretion or release of various cytokines that are known to influence bone remodeling, even if some recent data have challenged this hypothesis. However, in established osteoporosis, the possibility that enhanced cytokines activity may account for the progression of this disease remains unclear and controversial. We sought here to determine whether production of IL-1 beta, IL-6, TNF-alpha, IFN-gamma, GM-CSF and LIF, after direct stimulation in whole blood, was different in healthy (n = 30) or osteoporotic postmenopausal women (n = 24) and whether lumbar bone density (1-BMD) correlated with the values of cytokine production observed in these conditions. A significant difference was observed between the osteoporotic and control subjects for IL-1 beta (p < 0.0001), IL-6 (p < 0.001) and TNF-alpha (p = 0.027) productions, the values being higher in the osteoporotic women. No significant differences between the groups were observed for IFN-gamma (p = 0.51), GM-CSF (p = 0.70) or LIF (p = 0.97). In the whole population, statistically significant negative correlations were observed between lumbar BMD and IL-1 beta (r = -0.46) (p < 0.0005), IL-6 (r = -0.50) (p < 0.0001) and TNF-alpha (r = -0.39) (p < 0.005) production while no such correlations were observed for IFN-gamma, GM-CSF or LIF. In conclusion, the study of cytokine production by immune cells cultured in autologous whole blood suggests that in women more than 10 years past the menopause and presenting a decrease in lumbar bone density corresponding to the new WHO definition of "osteoporosis', production of IL-1 beta, IL-6 and TNF-alpha is still increased compared to controls matched for age and ovarian function, while no differences are reported for IFN-gamma, GM-CSF or LIF production.

The pathophysiology of chronic rejection.

The understanding of chronic rejection has been greatly enhanced by the use of genetically controlled experimental models using inbred rats. Models that express all lesions encountered in human transplants are described. Findings of chronic rejection depend on genetic disparity, strength of the immunologic reaction, response to injury, and perpetuation of an ischemic state. Lesions of vasculopathy and parenchymal cell damage may proceed at different rates, but the vasculopathy seems reversible until healing occurs. The experimental models that have led us to significant understanding are described herein.

Effects of three avocado/soybean unsaponifiable mixtures on metalloproteinases, cytokines and prostaglandin E2 production by human articular chondrocytes.

The in-vitro effects of avocado and soybean unsaponifiable residues on neutral metalloproteinase activity, cytokines and prostaglandin E2 (PGE2) production by human articular chondrocytes were investigated. Avocado and soybean unsaponifiable residues were mixed in three ratios: 1:2 (A1S2), 2:1 (A2S1) or 1:1 (A2S2). Freshly isolated human chondrocytes were cultured for 72 h in the absence or presence of interleukin-1beta, (IL-1beta) (17 ng/ml), with or without unsaponifiable residue mixtures at a concentration of 10 microg/ml. A/S unsaponifiable residues were also tested separately at concentrations of 3.3, 6.6 and 10 microg/ml. All A/S unsaponifiable mixtures reduced the spontaneous production of stromelysin, interleukin-6 (IL-6), interleukin-8 (IL-8) and prostaglandin E2 (PGE2) by chrondrocytes. At concentrations of 3.3 and 6.6 microg/ml, A/S residues, tested separately, were potent inhibitors of the production of IL-8 and PGE2. Nevertheless, only avocado residue inhibited IL-6 production at these concentrations. A/S unsaponifiable mixtures had a more pronounced inhibitory effect on cytokine production than avocado or soybean residues added alone. As anticipated, IL-1beta induced a marked release of collagenase, stromelysin, IL-6, IL-8 and PGE2. A/S unsaponifiable mixtures partially reversed the IL-1 effects on chrondrocytes. These findings suggest a potential role for A/S unsaponifiable extracts in mitigating the deleterious effects of IL-1beta: on cartilage.

[Insect-resistant transgenic plants of Brassica napus and analysis of resistance in the plants].

Cotyledons, each with a 1-2 mm petiole at its base, were cut from axenic seedlings and infected with Agrobacterium tumefaciens. After 2-3 days of cocultivation, the cotyledon explants were transferred to MS selection medium containing 15 mg/L kanamycin and 4.5 mg/L 6-BA to induce shoot differentiation. Kanamycin-resistant shoots were subcultured on selection medium with 20-50 mg/L kanamycin for 3-6 months for eliminating escaped non-transformants, and then rooted on MS medium containing 25 mg/L kanamycin and 0.1 mg/L NAA. Whole plants were transplanted into soil and grew in the field. DNA Southern blot hybridization and polymerase chain reaction showed that some of the plants were positive when probed with the insecticidal crystal protein gene. The transgenic plants exhibited tolerant to pest insects such as Laphygma exigua and Pieris rapae in leaf feeding experiments Kanamycin-resistance and insect-resistance were maintained in the progeny. The foreign genes were delivered to the progeny according to Mendelian Law of single gene segregation.

[Synthesis and bio-activity of coumarin derivatives and studies on its relationships between activity and lipophilicity].

4-Methyl-7-hydroxy-6 or 8-allylcoumarin, a new type of radioprotectors, has poor solubility in water and in oil, which influences markedly its absorption in body and effectiveness of peroral administration. For improving its solubility, 14 coumarin derivatives were synthesized on the basis of increasing its hydro- or lipophilicity, and studied preliminarily on their toxicities, radioprotective activities, and relations between their hydro- or lipophilicity and activities. It is found that both compounds (5a, 6a), can be dissolved in ethyl oleate and the latter in water partially as well, retain the radioprotective activities basically, and improve the survival of 65% (P < 0.01) of mice exposed to 9.0 Gy 60Co gamma-ray when administered before irradiation. In synthesis, von Pechmann reaction was improved; 6-allyl intermediate was synthesized by the method of blocking the 8-position by iodine, and the process was studied. Mannich base was synthesized under high pressure by using CH2Cl2 as C1 synthon.

[A study of effects of head-down bed-rest simulated weightlessness on phonetic features of Chinese].

OBJECTIVE: To study the changes of phonetic features of Chinese speech during head-down bed-rest (HDBR) simulated weightlessness. METHOD: During -6 degrees HDBR in 6 healthy subjects (20-30 years), acoustic-phonetic features were analyzed. RESULT: The duration of utterance was slightly increase in the first two days, and recovered after the fourth day of HDBR; mean energy decreased along with time of bed rest, t-tests showed that the decrease in energy of utterances was very significant; a decrease in fundamental frequencies under HDBR was also significant. CONCLUSION: There were certain changes in the acoustic phonetic features under HDBR, some of them were significant.

Effects of sound preconditioning on hearing loss from low or middle-frequency noise exposure.

Objective. To explore prior noise exposures or sound conditioning as a moderator of hearing loss produced by traumatic exposure to low or middle-frequency noise. Method. Two experimental groups of guinea-pigs were conditioned using a 0.5 kHz octave band noise (OBN) at 85 dB, 6 h/d for 4 d. The subjects were allowed to recover for 3 d after conditioning. Then the first group was exposed to a 0.5 kHz OBN at 110 dB for 1 h, the second group was exposed to 1 kHz OBN at 110 dB for 1 h. Two control groups received 0.5 kHz and 1 kHz OBN respectively at 110 dB for 1 h without prior sound conditioning. Result. Hearing threshold shifts recorded at 48 h after the high-level noise exposure in conditioned groups and control groups demonstrated that conditioning provided significant protection on hearing threshold shift from low or middle frequency noise exposure. Histological examination revealed significantly less hair cell loss in the conditioned than in the control groups. In addition, malondialdehyde (MDA) levels in red blood cell (RBC) of conditioned groups were significantly lower as compared with that of the control groups. Conclusion. Low-frequency conditioning provided significant protection not only on hearing threshold shift caused by noise of the same frequency, but also on that caused by middle frequency noise.