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Microplastic pollution is a central issue of great concern in the current environmental field. Microplastic pollution in marine environmental media is widely reported, but the characteristics of microplastic pollution in deep sediments are rarely reported. Based on this, three sampling points were set up on the muddy coast near the Haizhou Bay, a typical aquaculture sea area, to analyze the characteristics of microplastic pollution in sediment column samples. The study showed that the abundance of microplastics in the sediments of the study area was(0.12 ± 0.07)n·g -1 , which was at the medium pollution level. The total amount of microplastics in the sediment column was 3.43-6.00 times the abundance of microplastics in the surface sediment (5 cm). The abundance of microplastics in the sediment column samples showed regional differences. There was no significant difference in the abundance of microplastics in the sediment at different depths, but the index decreased with the increase in depth. The relationship between sediment moisture content, depth, and microplastics indicated that the abundance of microplastics in sediment was related to the physical properties of the sediment. Transparent and black microplastics accounted for the highest proportion in each station. Fiber was the most common form of microplastics in the sediment, and microplastics with small particle size accounted for the majority. The density of microplastics did not prevent its appearance in the sediment. The pollution characteristics of microplastics varied greatly in different depths of sediments.

Background: Preoperative knowledge of mutational status of gastrointestinal stromal tumors (GISTs) is essential to guide the individualized precision therapy., Aim: To develop a combined model that integrates clinical and contrast-enhanced computed tomography (CE-CT) features to predict gastric GISTs with specific genetic mutations, namely KIT exon 11 mutations or KIT exon 11 codons 557-558 deletions., Methods: A total of 231 GIST patients with definitive genetic phenotypes were divided into a training dataset and a validation dataset in a 7:3 ratio. The models were constructed using selected clinical features, conventional CT features, and radiomics features extracted from abdominal CE-CT images. Three models were developed: Model CT sign , model CT sign + rad , and model CT sign + rad + clinic . The diagnostic performance of these models was evaluated using receiver operating characteristic (ROC) curve analysis and the Delong test., Results: The ROC analyses revealed that in the training cohort, the area under the curve (AUC) values for model CT sign , model CT sign + rad , and model CT sign + rad + clinic for predicting KIT exon 11 mutation were 0.743, 0.818, and 0.915, respectively. In the validation cohort, the AUC values for the same models were 0.670, 0.781, and 0.811, respectively. For predicting KIT exon 11 codons 557-558 deletions, the AUC values in the training cohort were 0.667, 0.842, and 0.720 for model CT sign , model CT sign + rad , and model CT sign + rad + clinic , respectively. In the validation cohort, the AUC values for the same models were 0.610, 0.782, and 0.795, respectively. Based on the decision curve analysis, it was determined that the model CT sign + rad + clinic had clinical significance and utility., Conclusion: Our findings demonstrate that the combined model CT sign + rad + clinic effectively distinguishes GISTs with KIT exon 11 mutation and KIT exon 11 codons 557-558 deletions. This combined model has the potential to be valuable in assessing the genotype of GISTs., Competing Interests: Conflict-of-interest statement: The authors have declared that no competing interests exist., (©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.)

We herein present an approach of photo-induced disproportionation for preparation of Type-I photodynamic agents. As a proof of concept, BODIPY-based photosensitizers were rationally designed and prepared. The photo-induced intermolecular electron transfer between homotypic chromophores leads to the disproportionation reaction, resulting in the formation of charged intermediates, cationic and anionic radicals. The cationic radicals efficiently oxidize the cellularimportant coenzyme, tetrahydrobiopterin (BH 4 ), and the anionic radicals transfer electrons to oxygen to produce superoxide radicals (O 2 - ⋅). One of our Type-I photodynamic agents not only self-assembles in water but also effectively targets the endoplasmic reticulum. It displayed excellent photocytotoxicity even in highly hypoxic environments (2 % O 2 ), with a half-maximal inhibitory concentration (IC 50 ) of 0.96 μM, and demonstrated outstanding antitumor efficacy in murine models bearing HeLa tumors., (© 2024 Wiley-VCH GmbH.)

Increasing storage root number is a pivotal approach to enhance both storage root (SR) yield and appearance quality of sweet potato. Here, 2-year field experiments were conducted to investigate the effect of 0 (K0), 120 (K1), 240 (K2), and 360 (K3) kg ha -1 potassium fertilizer (K 2 O) on lignin metabolism, root growth, storage root yield, and uniformity. The results demonstrated that potassium (K) application led to a decrease in the activities of key enzymes involved in lignin biosynthesis, including phenylalanine deaminase (PAL), 4-coumarate coenzyme A ligase (4-CL), cinnamic acid dehydrogenase (CAD), polyphenol oxidase (PPO), and peroxidase (POD). This resulted in a significant reduction in lignin and G-type lignin contents in potential SRs compared to K0 treatment within 10-30 days after planting (DAP). BJ553 exhibited a significant decrease in PAL activity, as well as lignin and G-type contents at 10 DAP, whereas YS25 showed delayed effects until 20 DAP. However, the number and distribution of secondary xylem conduits as well as the mid-column diameter area in roots were increased in K2 treatment. Interestingly, K2 treatment exhibited significantly larger potential SR diameter than other treatments at 15, 20, and 25 DAP. At harvest, K2 treatment increased the SR number, the single SR weight, and overall yield greatly compared with K0 treatment, with an average increase of 19.12%, 16.54%, and 16.92% respectively. The increase of SR number in BJ553 was higher than that of YS25. Furthermore, K2 treatment exhibited the lowest coefficient of variation for both SR length and diameter, indicating a higher yield of middle-sized SRs. In general, appropriate potassium application could effectively suppress lignin biosynthesis, leading to a reduction in the degree of pericycle lignification in potential SRs. This promotes an increase in the number of storage roots and ultimately enhances both yield and appearance quality of sweet potato. The effect of potassium fertilizer on lignin metabolism in BJ553 roots was earlier and resulted in a greater increase in the SR number compared to YS25., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Liu, Xv, Si, Shi, Ding, Tang, Xv, Shi and Liu.)

Background: Suitable in vitro models are needed to investigate urothelial epithelial to mesenchymal transition (EMT) and pro-fibrogenesis phenotype in bladder pain syndrome/interstitial cystitis (BPS/IC). This study is to establish a novel experimental BPS/IC cell model and explore how different concentrations of tumor necrosis factor (TNF)-α influence the EMT and pro-fibrogenesis phenotype of urothelial cells., Methods: SV-HUC-1 urothelial cells were cultured with 2, 10, or 50 ng/mL TNF-α to mimic chronic inflammatory stimulation. The EMT and pro-fibrogenesis phenotype, including production of collagen I and pro-fibrosis cytokines, were estimated after 72 h of culture., Results: The bladder urothelial cells of BPS/IC exhibited upregulated vimentin, TNF-α and TNF receptor, downregulated E-cadherin, and increased collagen I. Higher concentrations of TNF-α (10 and 50 ng/mL) produced an obvious mesenchymal morphology, enhanced invasion and migratory capacity, increased expression of vimentin, and decreased expression of E-cadherin. Collagen I was increased in cells treated with 2 and 10 ng/mL TNF-α after 72 h. Secretion of interleukin (IL)-6 and IL-8 was promoted with 10 and 50 ng/mL TNF-α, while that of IL-1β or transforming growth factor-β was unaffected. Slug and Smad2 were upregulated by TNF-α after 72 h. The Smad pathway was activated most strongly with 10 ng/mL TNF-α and Slug pathway activation was positively correlated with the concentration of TNF-α., Conclusions: Sustained 10 ng/mL TNF-α stimulation induced the EMT and pro-fibrogenesis phenotype resembling BPS/IC in SV-HUC-1 cells. Minor inflammatory stimulation induced the pro-fibrogenesis phenotype while severe inflammatory stimulation was more likely to produce significant EMT changes. Different degrees of activation of the Slug and Smad pathways may underlie this phenomenon., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://dx.doi.org/10.21037/tau-21-392). The authors have no conflicts of interest to declare except the funding, of which the funders had no role in this study., (2021 Translational Andrology and Urology. All rights reserved.)

Objective: Epilepsy of infancy with migrating focal seizures (EIMFS) is a rare and severe developmental epileptic encephalopathy. The aim of this study was to improve our understanding of EIMFS by using phenotype-genotype correlation., Methods: We recruited, performed clinical genetic testing, and summarized the clinical features and genetic characteristics in five patients with EIMFS in China., Results: The five recruited patients included 2 males and 3 females. The median age of seizure onset was 2 months (range, day 3 to 3 months). All patients exhibited the characteristics of clinically migrating focal motor (tonic or clonic) seizures. Typical migrating ictal electrical patterns were found in 1 patient; the remaining four patients presented with overlapping seizures with different areas of ictal onset in differing hemispheres. All the patients had the associated variants, including KCNT1, SCN1A, SCN2A, TBC1D24 and ALG1. All patients received two or more antiseizure medications, and 1 patient became seizure-free, 1 reported >75 % seizure reduction, 2 reported >50 % seizure reduction, and 1 patient showed no improvement. Varying degrees of psychomotor developmental delays were observed in all patients., Conclusions: The course of EIMFS could be related to the type of gene variant present, and different genes may have specific clinical features. Larger cohorts are required to elucidate such potential phenotype-genotype correlations., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Background: Treatment of neonatal seizures includes etiotropic and anticonvulsant treatments. However, anticonvulsant use in neonates is off-label and requires ethical review. Objective: To investigate the efficacy and safety of levetiracetam for neonatal seizures and to establish a predictive model. Methods: We retrospectively analyzed 125 neonatal seizure cases (phenobarbital 66 cases, levetiracetam 59 cases). The efficacy, safety and tolerability of levetiracetam were evaluated by cox regression survival analysis and a regression tree prediction model for the 16-week time point. Results: There was no significant difference between phenobarbital and levetiracetam treatment group in short-term efficacy ( p  > 0.05). But the cumulative survival function suggested that levetiracetam treatment group was better than phenobarbital ( p  = 0.026) in long-term efficacy evaluation. Neurodevelopmental assessments at 16 weeks showed that levetiracetam had better effect on the neurodevelopmental level (Gesell scores in response) than phenobarbital ( p  = 0.011). The main adverse events with levetiracetam were irritability and anorexia. According to the regression tree prediction model, the top three factors influencing the therapeutic effect were pre-treatment seizure frequency, age of onset and etiological classification. Conclusion: Levetiracetam shows good efficacy, safety and tolerability for the long-term neonatal seizure treatment.

The thread and spline synchronous rolling (TSSR) process is a new developed rolling process, which can form the different profiles simultaneously in the process and can ensure the consistency of the relative position of different profiles of parts. However, the multi-meshing motions are intercoupling and the multi-deformation characteristics are intercoupling during the forming process. It can easily result in dimension overshoot, and even does not make the synchronous rolling process go smoothly. Exploring the influence of controllable processing parameters on the synchronous rolling process, especially the geometric parameters of rolled parts, is helpful to determine the parameters and control the size error for a smooth rolling process. Thus, in this paper, the effects of controllable geometric parameters and motion parameters such as billet diameter, radial feed-in speed, and rotational speed of synchronous rolling die on the TSSR process have been studied. The synchronous rolling experimental scheme was determined using an orthogonal experimental design method, and the geometric parameters of different tooth profiles of rolled parts were measured and analyzed. The experimental results indicated that: the uncoordinated meshing movement between different tooth profiles is more likely to cause tooth error of the splined section of the part; variations of the processing parameters are more likely to cause fluctuations in the size of the splined section of the part, and change of the billet diameter mainly affects the outside diameter of the threaded and splined sections, and the threaded and splined pitches are mainly affected by the motion parameters of the synchronous rolling die; the motion parameters of the rolling die should be matched and the lower rotational speed needs to match the lower radial feed-in amount per revolution; the ideal dimensional accuracy can be obtained by using an appropriate processing parameter combination, for example, the pitch error of the splined section of the part is less than 0.5 μm under one set of experimental conditions in this paper.

To identify the effects of the neurokinin-1 receptor (NK1R) antagonist aprepitant in treating pelvic pain, micturition symptoms, and bladder inflammation in mice with experimental autoimmune cystitis (EAC) similar to bladder pain syndrome/interstitial cystitis (BPS/IC). Female C57BL/6 mice were divided into the following three groups: normal control, EAC, and EAC plus aprepitant. EAC was induced in mice by duplicate immunization with bladder homogenate. In the EAC model group, EAC mice were given PBS by gavage once a day during the fourth week. In the EAC plus aprepitant group, aprepitant was administered instead of PBS in the same way. After 4 weeks, pelvic pain threshold and urination habits of mice were analyzed, as well as the bladder weight to body weight ratio, and histologic assessment of the expression of IL-1β, TNF-α, intercellular adhesion molecule 1 (ICAM-1), and NK1R in bladder tissue. EAC mice mimicked the phenotype and pathophysiologic lesions of BPS/IC well. Compared to PBS-treated EAC mice, the mice treated with aprepitant exhibited higher pain threshold values, less number of total urine spots or small urine spots, lower bladder weight to body weight ratio, and reduced bladder inflammation with less mast cell infiltration and decreased expressions of IL-1β, TNF-α, and ICAM-1 in bladder tissue. There was no difference in NK1R expression in bladders treated with or without aprepitant. The NK1R antagonist aprepitant relieved pelvic pain, urinary symptoms, and bladder inflammation in EAC mice. This indicated that NK1R may be a novel therapeutic target in BPS/IC treatment.

Objective: To assess the dynamic changes in the average and peak spectral power of fast ripples (FRs) in the hippocampi after interventions with valproate sodium (VPA), carbenoxolone (CBX) and quinine (QUIN)., Method: Adult rats were used to establish a lithium-pilocarpine (pilo) epileptic model, and were assigned to a lithium-pilocarpine (PILO), VPA + PILO, QUIN + PILO or CBX + PILO group. Intracranial electroencephalography was performed before and after status epilepticus (SE). The hippocampal connexin (CX) 43, CX32 and CX36 expressions were analyzed via western blotting., Results: The time required for the disappearance of SE after chloral hydrate injection was lower in the intervention groups than in the PILO group (p < 0.05). Seizures induced CX43 expression, but had no significant effects on CX36 or CX32 expressions. Pretreatment with VPA, QUIN and CBX inhibited CX43, CX36 and CX32 expression after SE. The average spectral power of the FRs was significantly lower in the VPA + PILO and QUIN + PILO groups than in the PILO group at 10 min after SE, 10 min before chloral hydrate injection, and 10 min after chloral hydrate injection (p < 0.05). The average spectral power of FRs was lower in the CBX + PILO group than in the PILO group at 10 min after SE (p < 0.05). The average spectral power of FRs in the 3 intervention groups recovered to the baseline level at 10 min after chloral hydrate injection and persisted for 3 days after SE. The dynamic changes in the average and peak spectral power of FRs were similar., Significance: After SE, CX may participate in pathological FR generation by establishing abnormal electrical synaptic transmission. Gap junction blockers can inhibit various CX expressions, and thus decrease FR energy and alleviate the degree of seizure. These findings could contribute to the development of new anti-epileptic drugs with novel mechanistic targets., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The aim of this study is to identify whether vaccinating twice with bladder homogenate can establish a new model of experimental autoimmune cystitis (EAC) in C57BL/6 strain mice. C57BL/6 mice were vaccinated with bladder homogenate in complete Freund's adjuvant (CFA) and boost immunized with bladder homogenate in incomplete Freund's adjuvant (IFA) after 2 weeks were used as the EAC model. Mice immunized with phosphate-buffered saline (PBS) in CFA or IFA were used as the control. Micturition habits and suprapubic-pelvic pain threshold were measured 4 weeks after primary immunization. Bladder to body weight ratios and expression of inflammatory cytokines and neurokinin 1 receptor (NK1R) were then examined. Histologic and immunohistochemical examination of the bladder was carried out, and IL-1β, IFN-γ, and TNF-α production by the kidneys, liver, and lungs was also tested. Double-immunized mice were extensively sensitive to pressure applied on the pelvic area (P < 0.001). Compared to single-immunized mice or controls, double-immunized mice showed more micturition frequency, lower urine output per micturition, higher bladder to body weight ratio, and significant elevation in the expression of inflammatory cytokines, including IL-1β, IL-4, IL-6, IL-10, IFN-γ, and TNF-α (all P < 0.05). NK1R gene expression was significantly increased in double-immunized mice compared to the other three groups (P < 0.001). A nonspecific immune response occurred in the liver but was much weaker than bladder inflammation. Our dual immunization EAC model in C57BL/6 mice can effectively mimic the symptoms and pathophysiologic characteristics of BPS/IC and thus can be widely used to investigate the pathogenesis and therapeutic strategies of BPS/IC.

Objective: To analyze spectral and spatial signatures of high frequency oscillations (HFOs), which include ripples and fast ripples (FRs, >200 Hz) by quantitatively assessing average and peak spectral power in a rat model of different stages of epileptogenesis., Methods: The lithium-pilocarpine model of temporal lobe epilepsy was used. The acute phase of epilepsy was assessed by recording intracranial electroencephalography (EEG) activity for 1 day after status epilepticus (SE). The chronic phase of epilepsy, including spontaneous recurrent seizures (SRSs), was assessed by recording EEG activity for 28 days after SE. Average and peak spectral power of five frequency bands of EEG signals in CA1, CA3, and DG regions of the hippocampus were analyzed with wavelet and digital filter., Results: FRs occurred in the hippocampus in the animal model. Significant dynamic changes in the spectral power of FRS were identified in CA1 and CA3. The average spectral power of ripples increased at 20 min before SE ( p  < 0.05), peaked at 10 min before diazepam injection. It decreased at 10 min after diazepam ( p  < 0.05) and returned to baseline after 1 h. The average spectral power of FRs increased at 30 min before SE ( p  < 0.05) and peaked at 10 min before diazepam. It decreased at 10 min after diazepam ( p  < 0.05) and returned to baseline at 2 h after injection. The dynamic changes were similar between average and peak spectral power of FRs. Average and peak spectral power of both ripples and FRs in the chronic phase showed a gradual downward trend compared with normal rats 14 days after SE., Significance: The spectral power of HFOs may be utilized to distinguish between normal and pathologic HFOs. Ictal average and peak spectral power of FRs were two parameters for predicting acute epileptic seizures, which could be used as a new quantitative biomarker and early warning marker of seizure. Changes in interictal HFOs power in the hippocampus at the chronic stage may be not related to seizure occurrence.

Cobalt hydroxide/cadmium sulfide composite was prepared using an easy coprecipitation strategy. The field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) confirmed that Co(OH)2 nanometer particles were modified on CdS. Even without noble-metal cocatalyst, the photocatalytic H2 evolution over CdS after Co(OH)2 loaded was evidently increased. The most excellent Co(OH)2 of 6.8 mol %, resulted in a H2 generation rate of 61 μmol h(-1) g(-1), which exceeded that of pure CdS by a factor of 41 times. Surface photovoltage (SPV) and surface photocurrent (SPC) investigations revealed that the photogenerated electrons could be captured by the loaded Co(OH)2 nanoparticles. The interface formed between Co(OH)2 and CdS is vital to the enhancement of photocatalytic H2 generation. Electrochemical measurement results indicated that another reason for the enhanced photocatalytic activity of Co(OH)2/CdS catalyst is that Co(OH)2 has outstanding H2 generation activity.

Climate changes within Cenozoic extreme climate events such as the Paleocene-Eocene Thermal Maximum and the First Oligocene Glacial provide good opportunities to estimate the global climate trends in our present and future life. However, quantitative paleotemperatures data for Cenozoic climatic reconstruction are still lacking, hindering a better understanding of the past and future climate conditions. In this contribution, quantitative paleotemperatures were determined by fluid inclusion homogenization temperature (Th) data from continental halite of the first member of the Shahejie Formation (SF1; probably late Eocene to early Oligocene) in Bohai Bay Basin, North China. The primary textures of the SF1 halite typified by cumulate and chevron halite suggest halite deposited in a shallow saline water and halite Th can serve as an temperature proxy. In total, one-hundred-twenty-one Th data from primary and single-phase aqueous fluid inclusions with different depths were acquired by the cooling nucleation method. The results show that all Th range from 17.7°C to 50.7°C,with the maximum homogenization temperatures (ThMAX) of 50.5°C at the depth of 3028.04 m and 50.7°C at 3188.61 m, respectively. Both the ThMAX presented here are significantly higher than the highest temperature recorded in this region since 1954 and agree with global temperature models for the year 2100 predicted by the Intergovernmental Panel on Climate Change.

Four novel metal-organic frameworks (MOFs) based on high-nuclear metal carboxylate clusters, namely, [Zn(4)(L)(2)(μ(3)-OH)(2)(H(2)O)(1.5)]·2H(2)O (1), [Zn(5)Na(L)(2)(μ(3)-OH)(4)(CH(3)CH(2)O)(H(2)O)(2)] (2), [Cd(4)(L)(2)(BIME)(0.5)(μ(3)-OH)(2)(H(2)O)(1.5)]·2H(2)O (3), and [Zn(4)(L)(2)(BET)(0.5)(μ(3)-OH)(2)(H(2)O)] (4), where H(3)L = (3,5-dicarboxyl-phenyl)-(4-(2'-carboxyl-phenyl)-benzyl)ether, BET = 1,1'-(2'-oxybis(ethane-2,1-diyl))bis(1,2,4-triazol-1-yl), BIME = 1,2-bis(imidazol-1-yl)ethane, have been synthesized under hydrothermal conditions. In 1, each planar octanuclear zinc cluster [Zn(8)(μ(3)-OH)(8)(CO(2))(12)(H(2)O)(3)] is linked by twelve L anions to give an unusual (3,12)-connected framework with (4(3))(2)(4(20)·6(28)·8(18)) topology. In 2, dodecanuclear heterometallic clusters [Zn(10)Na(2)(μ(3)-OH)(8)(CO(2))(12)(CH(3)CH(2)O)(2)(H(2)O)(4)] are surrounded by twelve L anions to form a (3,12)-connected net with the same topology as 1. However, 3 exhibits a rare (3,14)-connected (4(3))(3(2)4)(3(4)·4(20)·5(14)·6(34)·7(11)·8(8)) net based on octanuclear cadmium cluster [Cd(8)(BIME)(2)(μ(3)-OH)(4)(CO(2))(12)(H(2)O)(4)]·2H(2)O as a 14-connected node and H(3)L as a 3-connected node. In 4, each octanuclear zinc cluster [Zn(8)(BET)(2)(μ(3)-OH)(4)(CO(2))(12)(H(2)O)(2)] is linked by twelve L anions to furnish a (3,14)-connected net with the same topology as 3. The optical energy gaps and photoluminescence were investigated for the compounds. Moreover, compounds 1-4 exhibit good photocatalytic activities for degradation of methylene blue (MB) under UV irradiation and show good stability towards UV photocatalysis. In addition, 1 and 4 display a photocurrent density under several on-off cycles of illumination.

Nitroalkanes underwent fast additions to a variety of structurally diverse aldehydes under the catalysis of d-aminoacylase in DMSO. The influences of reaction conditions including solvents, temperature, enzyme concentration and molar ratio of substrates were systematically investigated. Seventeen products were obtained in short time with moderate to high yields. It is the first report on hydrolase-catalyzed fast Henry reaction in organic solvent., (Copyright 2009 Elsevier B.V. All rights reserved.)

A zinc-dependent acylase, D-aminoacylase from Escherichia. Coli, displays a promiscuous activity to catalyze the carbon-carbon bond formation reaction of 1,3-dicarbonyl compounds to methyl vinyl ketone in organic media.

N-methylimidazole, a molecular solvent, but also, in cationic form, a component of 1-alkyl-3-methylimidazolium ([C(n)MIM]+) ionic liquids, showed promise as an additive in accelerating remarkably transesterification catalyzed by lipase acrylic resin from Candida antarctica (CAL-B).

Eightfold higher yields and three times faster reaction rates were achieved by means of using a mixture solvent system composed of 90% acetone and 10% [BMIM]BF4 in the lipase-catalyzed regioselective synthesis of polymerizable ester of nucleoside drugs.

A basic ionic liquid, 1-methyl-3-butylimidazolium hydroxide ([bmIm]OH), has been introduced as a catalyst and reaction medium for the Markovnikov addition of N-heterocycles to vinyl esters under mild conditions. The evidence for the role of this basic ionic liquid [bmIm]OH in promoting the Markovnikov addition has been given. On the basis of the evidence, a mechanism was postulated.

Enzymatic transesterification of glucose with the vinyl ester of non-steroidal anti-inflammatory drugs (NSAIDs) was in organic media performed for synthesis of novel NSAIDs-glucose conjugates. Glucose was regioselectively acylated at the 6-hydroxyl group. The indomethacin-glucose conjugate and ketoprofen-glucose conjugate were produced by the catalysis of alkaline protease from Bacillus subtilis in the respective yields of 42% (over 48 h) and 63% (over 40 h). The etodolac-glucose conjugate was obtained in 26% yield (over 144 h) by lipase from Candida antarctica.

Lipase-catalyzed synthesis of potential multifunctional ribavirin derivatives was performed in acetone. Divinyl dicarboxylates with different chain lengths (C4, C6, C9, C10) were used as acyl donors and the reactions were catalyzed by lipase immobilized on acrylic resin from Candida antarctica (CAL-B). Ribavirin was regioselectivly acylated at the primary hydroxyl groups and the corresponding vinyl esters (C4, C6, C9, C10) were prepared in respective yields of 48%, 65%, 54%, 55%.

Objective: To study the characteristics of human body dynamic responses to landing impact., Method: Five healthy young men were exposed to 4-10 G for 50-80 ms half-sine acceleration pulse at 20 degrees supine angle and 10 G for 50 ms impact at 30 degrees to 60 degrees supine angles. The acceleration curves on the dropping platform of the impact tower, the seat, the human head, shoulder, chest and ilium, as well as ECG of the subjects were recorded., Result: The peaks of acceleration at the subject head, shoulder, chest, and ilium along chest-back direction rose with the increase of the impact level. The overshoots of acceleration at the subject head along head-ilium direction and chest-back direction were 93% and 102% respectively for 10 G at 20 degrees supine angle. With increase of supine angle, acceleration response at the subject along chest-back direction decreased. Acceleration response at the subject head along head-ilium direction was minimum at 40 degrees supine angle., Conclusion: Transfer function of the human body to landing impact demonstrated that human body had a series of resonance frequencies which were 25 Hz, 34 Hz, 39 Hz, 43 Hz, 50 Hz, 64 Hz, and 70 Hz respectively.

Landing impact is the dynamic factor that manned spaceship will inevitably meet after the mission has been completed, and impact force may cause damages to human tissues [correction of tissuses] and organs, even death. This paper described the characteristics of pathological and dynamic response of human body to landing impact, and discussed various related factors such as impact angle, fetters, design of cushion, harness and terrain condition. Medical evaluation of +Gx, +Gz, +/- Gy impacts were summarized.

Objective. To study changes of human dynamic response to landing impact in selected body orientations. Method. Five healthy young men were exposed to 10 G, 50 ms half-sine acceleration pulses. The angle included between human head-ilium axis and impact force direction was 30 degrees-70 degrees. The acceleration responses at head, shoulder, chest and ilium of the subjects were recorded along head-ilium and chest-back directions. Result. Within limits of the experiments, the minimum peak response at the head along head-ilium direction was 10.36 +/- 2.44 G at 50 degrees, and the maximum was 18.07 +/- 3.29 G at 70 degrees. The minimum peak response at the chest along head-ilium direction was 10.39 +/- 3.97 G at 70 degrees, and the maximum was 15.42 +/- 3.61 G at 60 degrees. The minimum peak response at the head along chest-back direction was 7.58 +/- 1.18 G at 30 degrees, and the maximum was 18.89 +/- 1.85 G at 70 degrees. The minimum peak response at the chest along chest-back direction was 7.21 +/- 1.99 G at 30 degrees, and the maximum was 17.67 +/- 2.16 G at 70 degrees. Conclusion. It was inferred that the best body orientation angle for landing impact might be 50 degrees.

The background for developing conjugate vaccines for shigellosis composed of the O-specific polysaccharide (O-SP) bound to a protein is described elsewhere (C. Y. Chu, R. Schneerson, and J. B. Robbins, submitted for publication). Briefly, there is direct evidence for type (lipopolysaccharide [LPS])-specific protection after infection with the wild type or with attenuated strains of shigellae. Prospective studies of Israeli armed forces recruits show a correlation between preexisting serum immunoglobulin G (IgG) LPS antibodies and resistance to shigellosis (D. Cohen, M. S. Green, C. Block, R. Slephon, and I. Ofek, J. Clin. Microbiol. 29:386-389, 1991). In order to elicit IgG LPS-specific antibodies to Shigella dysenteriae type 1, the O-SP of this pathogen was purified and bound to tetanus toxoid (TT) by three schemes. The most immunogenic used a modification of a published method (C. Y. Chu, R. Schneerson, J. B. Robbins, and S. C. Rastogi, Infect. Immun. 40:245-256, 1983). The resultant O-SP-TT conjugates were stable and elicited high levels of IgG O-SP antibodies and booster responses in young mice when injected subcutaneously in saline at 1/10 the proposed human dose. Adsorption onto alum or concurrent administration with monophosphoryl lipid A enhanced both the IgG and IgM antibody responses to the O-SP of the conjugate; both the nonadsorbed and adsorbed conjugates elicited higher rises of IgG than of IgM antibodies. Clinical evaluations of S. dysenteriae type 1 O-SP-TT conjugates are planned.

The effect of pulmonary surfactant on small airway function was evaluated in 32 patients undergoing lobectomy or pneumonectomy due to local lung diseases. Surfactant of lung tissue obtained from the surgical specimens and airway lining surfactant obtained from bronchoalveolar lavage were measured. Before surgery, small airway function testing including CV/VC, CC/TLC, delta N2/L,V50 and V25 were measured in each patient. They were then divided into two groups: group I with normal function and group II abnormal function. The results showed that pulmonary surfactant in bronchoalveolar lavage fluid was statistically less in group II than in group I, whereas that in the lung tissue had no significantly difference between the two groups. It is therefore conceivable that the decrease of small airway function, besides as a result of its structure or pathologic abnormalities, could be due to the decrease in airway surfactant as well.