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Polar organic chemical integrative samplers (POCIS) are promising devices for measuring time-weighted average concentrations of hydrophilic compounds in aquatic environments. However, the mechanism of POCIS uptake remains unclear. This study characterizes the permeation properties of polyethersulfone and polytetrafluoroethylene and the sorption properties of Oasis HLB (Waters), Envi-Carb (Supelco), and Oasis WAX (Waters) under identical conditions via calibration experiments of the POCIS. Plant protection products, neonicotinoid herbicides, and linear alkyl benzene sulfonates (LAS) were tested. The permeation experimental results suggested that the penetration rate constants (km) with high Kow values (Kow: octanol–water partition coefficient) were low, which indicated that the sorption of chemicals on the membrane may constitute a limiting factor for the permeation. The sorption experiments indicated that the sorption rate constants (ks) depended on the type of sorbent instead of the Kow values. Low ks/km ratios were obtained for chemicals with low Kow values, which implied that the POCIS uptake for highly hydrophilic compounds was controlled by both membrane and sorbent kinetics. The km and ks values corresponded to the model and predicted the values of the sampling rates (Rs) for the LAS. These findings revealed the possibility of using ks and km values to predict Rs values.

Polar organic chemical integrative sampler (POCIS) devices have been suggested for monitoring contaminant fluctuations in aquatic environments, resulting from chemical leak accidents. However, the response of the POCIS device in the emergency condition in natural water remains unclear. The response of the POCIS device to contaminant fluctuation was investigated using a simplified chamber test with tap water and a channel test with natural water in the present study. The fluctuation in the chamber and the channel replicated the condition of river water under a chemical leak scenario (maximum concentration: 1–10 μg L–1, half-life: 1 d). The target chemicals were neonicotinoid pesticides (dinotefuran, clothianidin, thiamethoxam, imidacloprid, acetamiprid, and thiacloprid) and bisphenol A. The ratio of the POCIS measured value to the time-weighted average value of grab samplings (POCIS/TWA) for the channel test (temperature: 15 °C, flow velocity: 15 cm s–1) ranged from 61% (clothianidin) to 133% (thiacloprid). The results indicated that the POCIS device could be effectively used as a monitoring device in an aquatic environment under the chemical leak scenario. In addition, the differences in the POCIS/TWA ratios obtained from the chamber test and the channel test were in the range of –50 to 50%, except for a few data points. Thus, the simplified chamber test could be used as a validation system to evaluate the POCIS device at a low cost.

A polar organic chemical integrative sampler (POCIS) was developed for the detection of linear alkylbenzene sulfonates (LASs), which are one of the most widely used chemicals globally and represent a type of surfactant agent. Owing to natural disasters and accidents, these LASs have a potential risk to leak into aquatic environments at high concentrations, and thus far, passive sampling methods have not yet been applied in their detection as, being a sorptive compound, they do not easily permeate the membrane of passive samplers. In the present study, the LASs were significantly sorbed onto the polyethersulfonate (PES) membrane, suggesting that the less sorptive polytetrafluoroethylene (PTFE) membrane is suitable for application in the POCIS device. Calibration experiments showed that the developed POCIS device with Oasis WAX as the sorbent and PTFE as the membrane filter had linear ranges > 28 d and sampling rates ranging from 0.035 ± 0.007 (tetradecylbenzenesulfonate) to 0.139 ± 0.024 (dodecylbenzenesulfonate) L d–1. Furthermore, this developed POCIS device was validated under non-steady-state conditions via both chamber and field tests. The condition in the chamber test replicated the LAS concentration change in rivers contaminated by LAS-leaked accidents. The time-weighted average concentrations of dodecylbenzenesulfonate measured using the improved POCIS agreed well with those obtained via grab sampling within 21% over the sampling period of 14 d in both the chamber and field tests. Therefore, the developed POCIS can be successfully applied in the detection of LASs in LAS-contaminated aquatic environments owing to chemical leak accidents.

We have developed a database for membrane protein functions, which has more than 3000 experimental data on functionally important amino acid residues in membrane proteins along with sequence, structure and literature information. Further, we have proposed different methods for identifying membrane proteins based on their functions: (i) discrimination of membrane transport proteins from other globular and membrane proteins and classifying them into channels/pores, electrochemical and active transporters, and (ii) β-signal for the insertion of mitochondrial β-barrel outer membrane proteins and potential targets. Our method showed an accuracy of 82% in discriminating transport proteins and 68% to classify them into three different transporters. In addition, we have identified a motif for targeting β-signal and potential candidates for mitochondrial β-barrel membrane proteins. Our methods can be used as effective tools for genome-wide annotations., {"references":["T. Hirokawa, S. 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We have experienced two cases of congenital di v erticula of the male anterior urethra, one of which had a stone. The first case w a s a 25 years old male with a chief complaint of frequency and subsequent dribbling away of urine. History ; This patient s t ates that he has been suffering from frequency and subsequent dribbling away of urine for the past month. This condition continued in spite of various treatment. There are no changes on inspection and palpation in the local portion. Diagnosis of diverticulum 4.7x1.7 cm in size in the pars bulbo s a was made from the urethro gr a phy. A sma l l finger tip sized ostium was discovered by urethroscopic examination in the pars bulbosa. Th e diverticulum was excised through the perineum and the result of operation progressed favourably. Histo l ogically, there was on epithelium and substantia spongiosa was found under the fibrous tissue. The second case was a 27 years old baschelor with a chief complaint of urethral secretion. This patient asserts that he had received on operation of the sac at the age of 5, and suffered from gonorrhoe when 21. Since about two years, this p atient had pus-like secretion from the external urethral meatus, but had no pain during micturition, obstruction of urination and subsequent dribbling, etc. He thought that he had yet been suffering from gonorrhoe, and in spite of . various treatment, this condition did not improve. A walnut sized, firm and round tumor was palpated about the base of the penis . When the tumor was palpated, secretion of pus-like material was observed i n the urethral meatus. By pla i n roentgenogram, a store was confirmed in the diverticulum. And by injecting opaque contrast medium in to the tumor, confirmation of the connetcion of urethra was obtained. The diverticulum, 2.5 x1.9 x1.7 cm in size, containing a white, flat, ovalstone was removed. This diverticulum had a stalk measuring 1.0x0.25 cm, opering into the right side urethral wall. His t ologically, Metaplasia of columnar epithelium into squamous epithelium with marked keratinisation.

The nature of cell-dependent antibody (CDA) and the mechanism of inhibition of antibody-dependent cellular cytotoxicity (ADCC) were studied in the ADCC assay system in which culture cells of methylcholanthrene-induced rat fibrosarcoma (KMT-50) were used as target cells, xenogeneic antiserum (rabbit anti-KMT-50) as the CDA, and human peripheral blood leucocytes (PBL) as effector cells, respectively. By using protein-A Sepharose CL-4B affinity column chromatography of rabbit anti-KMT-50 serum, CDA was shown to bind protein A. Complement dependent-cytotoxicity (CDC), however, was demonstrated in both the adsorbed fraction (eluate) and the non-adsorbed fraction (effluent) to protein A from the same affinity column chromatography. These data confirmed that CDA was IgG with an intact Fc portion. Inhibition of ADCC occurred by pretreatment of effector cells with rabbit anti-effector (human PBL) serum even with extremely small amounts of antiserum. Such inhibition was demonstrated with the eluate but not with the effluent from protein-A Sepharose CL-4B affinity column chromatography of rabbit anti-effector serum. F(ab')2 fragments of the same eluate (IgG) did not inhibit the ADCC activity. These data showed that the inhibition of ADCC was induced by the blocking of Fc receptors of effector cells with the Fc portions of IgG in anti-effector serum. The data obtained indicate the usefulness of protein A in separation and analysis of CDA and in investigation of the inhibitory mechanisms of ADCC.

We have experienced two cases of congenital di v erticula of the male anterior urethra, one of which had a stone. The first case w a s a 25 years old male with a chief complaint of frequency and subsequent dribbling away of urine. History ; This patient s t ates that he has been suffering from frequency and subsequent dribbling away of urine for the past month. This condition continued in spite of various treatment. There are no changes on inspection and palpation in the local portion. Diagnosis of diverticulum 4.7x1.7 cm in size in the pars bulbo s a was made from the urethro gr a phy. A sma l l finger tip sized ostium was discovered by urethroscopic examination in the pars bulbosa. Th e diverticulum was excised through the perineum and the result of operation progressed favourably. Histo l ogically, there was on epithelium and substantia spongiosa was found under the fibrous tissue. The second case was a 27 years old baschelor with a chief complaint of urethral secretion. This patient asserts that he had received on operation of the sac at the age of 5, and suffered from gonorrhoe when 21. Since about two years, this p atient had pus-like secretion from the external urethral meatus, but had no pain during micturition, obstruction of urination and subsequent dribbling, etc. He thought that he had yet been suffering from gonorrhoe, and in spite of . various treatment, this condition did not improve. A walnut sized, firm and round tumor was palpated about the base of the penis . When the tumor was palpated, secretion of pus-like material was observed i n the urethral meatus. By pla i n roentgenogram, a store was confirmed in the diverticulum. And by injecting opaque contrast medium in to the tumor, confirmation of the connetcion of urethra was obtained. The diverticulum, 2.5 x1.9 x1.7 cm in size, containing a white, flat, ovalstone was removed. This diverticulum had a stalk measuring 1.0x0.25 cm, opering into the right side urethral wall. His t ologically, Metaplasia