Association between varicose veins anatomical pattern and procedural complications following endovascular laser photothermolysis for chronic venous insufficiency

We sought to assess clinical characteristics and pattern of collateral network involvement associated with development of truncal (systematized) versus diffuse/non-truncal (non-systematized) varicose veins (VVs) in patients undergoing endovascular laser photothermolysis for chronic venous insufficiency (CVI). Secondly, we aimed to assess whether the type of VVs influenced the procedural complications of endovascular laser therapy. A total of 508 patients with hydrostatic VVs of the lower limbs who underwent endovenous laser treatment were included, out of which 84.1% (n=427) had truncal VVs (group 1) and 15.9% (n=81) had diffuse (non-systematized) VVs (group 2). Patients with truncal varices were significantly older (47.50±12.80 vs 43.15±11.75 years, P=0.004) and those with associated connective tissue disorders were more prone to present diffuse VVs (P=0.004). Patients in group 1 presented a significantly higher number of Cockett 1 (P=0.0017), Cockett 2 (P=0.0137), Sherman (P<0.0001), and Hunter (P=0.0011) perforator veins compared to group 2, who presented a higher incidence of Kosinski perforators (P<0.0001). There were no significant differences regarding postoperative complications: thrombophlebitis (P=0.773), local inflammation (P=0.471), pain (P=0.243), paresthesia (P=1.000), or burning sensation (P=0.632). Patients with more advanced CEAP (clinical, etiologic, anatomic, pathophysiologic) classes were older (P<0.0001), more were males (39.05 vs 27.77%, P=0.0084), more were prone to present ulcers (P<0.0001) and local hyperthermia (P=0.019), and presented for endovenous phlebectomy after a longer time from symptom onset. In patients with CVI, systematized VVs were associated with a more severe clinical status and a distinct anatomical pattern of perforators network compared to non-systematized VVs, which is more common in advanced stages.

Degradation and inactivation of adenovirus in water by photo-electro-oxidation / Degradação e inativação de adenovírus na água por fotoeletrooxidação

The present study analyzed the efficiency of the photo-electro-oxidation process as a method for degradation and inactivation of adenovirus in water. The experimental design employed a solution prepared from sterile water containing 5.107 genomic copies/L (gc/L) of a standard strain of human adenovirus type 5 (HAdV-5) divided into two equal parts, one to serve as control and one treated by photo-electro-oxidation (PEO) for 3 hours and with a 5A current. Samples collected throughout the exposure process were analyzed by real-time polymerase chain reaction (qPCR) for viral genome identification and quantitation. Prior to gene extraction, a parallel DNAse treatment step was carried out to assess the integrity of viral particles. Integrated cell culture (ICC) analyses assessed the viability of infection in a cell culture. The tested process proved effective for viral degradation, with a 7 log10 reduction in viral load after 60 minutes of treatment. The DNAse-treated samples exhibited complete reduction of viral load after a 75 minute exposure to the process, and ICC analyses showed completely non-viable viral particles at 30 minutes of treatment.

Resumo O presente estudo analisou a eficiência do processo de fotoeletrooxidação como metodologia para a degradação e inativação de adenovírus em água. A concepção experimental emprega uma solução preparada a partir de água estéril contendo 5,107 cópias genômicas/L (gc/L) de uma amostra padrão de adenovírus humano tipo 5 (HAdV-5), dividida em duas partes iguais, uma para servir como controle e outra tratada por fotoeletrooxidação (PEO) durante 3 horas e com uma corrente de 5A. As amostras recolhidas durante o processo de exposição foram analisadas por PCR quantitativo em tempo real (qPCR) para identificação e quantificação do genoma viral. Antes da extração de ácidos nucleicos, um passo de tratamento com DNAse paralelo foi realizado para avaliar a integridade das partículas virais. Um ensaio de qPCR integrado à cultura de células (ICC-qPCR) permitiu analisar a viabilidade de infecção em uma cultura de células. O processo mostrou-se eficaz testada para a degradação viral, com uma redução de 7 log10 da carga viral após 60 minutos de tratamento. As amostras tratadas com DNAse exibiram redução completa da carga viral após uma exposição de 75 minutos ao processo, e a análise de ICC-qPCR mostrou partículas virais completamente não-viáveis ​​em 30 minutos de tratamento.

Cytotoxicity assays to evaluate tannery effluents treated by photoelectrooxidation / Ensaios de citotoxicidade na avaliação de efluentes de curtume tratados por fotoeletrooxidação

The advanced oxidation process (AOP) is used to increase the treatment efficiency of effluents however, it is necessary to compare the toxicity of treated and untreated effluents to evaluate if the decontamination process does not cause any biological harm. Cultured cells have been previously used to assess the genotoxic and cytotoxic potential of various compounds. Hence, the aim of this work was to assess the applicability of cytotoxicity assays to evaluate the toxicity related to the AOP treatment. Samples of an industrial effluent were collected after their treatment by a conventional method. Cytotoxicity of standard and AOP treated effluents was assessed in CRIB and HEp-2 cell line using the MTT and neutral red assays. We observed decrease at cell viability in the both assays (50% MTT and 13% NRU) when cells were exposed to the AOP treatment in the highest concentration. Thus, cytotoxic assays in cultured cells can be explored as an useful method to evaluate toxicity as well as to optimize effluents treatment process.

Resumo O processo de oxidação avançada (POA) tem sido usado para aumentar a eficiência do tratamento de efluentes; no entanto, é necessário comparar a toxicidade de efluentes tratados e não tratados para avaliar se o processo de descontaminação não é capaz de causar algum risco biológico. Cultivos celulares têm sido utilizados para avaliar o potencial genotóxico e citotóxico de vários compostos. Assim, o objetivo deste trabalho foi avaliar a aplicabilidade de ensaios de citotoxicidade para avaliar a toxicidade relacionada ao tratamento com POA. As amostras de um efluente industrial foram recolhidas após o tratamento por um método convencional. A citotoxicidade dos efluentes padrão e tratado com POA foi avaliada nas linhagens celulares CRIB e HEp-2 usando os ensaios do MTT e do vermelho neutro. Observou-se diminuição da viabilidade celular em ambos os ensaios (50% MTT e 13% VN) quando as células foram expostas à concentração mais elevada do efluente tratado com POA. Assim, os ensaios de citotoxicidade em cultivos celulares podem ser explorados como um método útil para avaliar a toxicidade, bem como para otimizar os processos de tratamento de efluentes.

Toxicity effects of nickel electroplating effluents treated by photoelectrooxidation in the industries of the Sinos River Basin / Avaliação do efeito tóxico de efluentes oriundos da indústria galvânica na região da Bacia do Rio dos Sinos após o tratamento pelo processo de fotoeletrooxidação

The Sinos river Basin is an industrial region with many tanneries and electroplating plants in southern Brazil. The wastewater generated by electroplating contains high loads of salts and metals that have to be treated before discharge. After conventional treatment, this study applied an advanced oxidative process to degrade organic additives in the electroplating bright nickel baths effluent. Synthetic rinsing water was submitted to physical-chemical coagulation for nickel removal. The sample was submitted to ecotoxicity tests, and the effluent was treated by photoelectrooxidation (PEO). The effects of current density and treatment time were evaluated. The concentration of total organic carbon (TOC) was 38% lower. The toxicity tests of the effluent treated using PEO revealed that the organic additives were partially degraded and the concentration that is toxic for test organisms was reduced.

A Bacia do Rio dos Sinos é uma região do Sul do Brasil que sedia um importante pólo da indústria coureiro-calçadista incluindo, desde o beneficiamento das peles, em curtumes, à fabricação dos acessórios, em indústrias metalúrgicas e de galvanoplastia. O efluente gerado por processos galvânicos contém carga elevada de sais e metais que devem ser tratados antes do descarte. Neste artigo foi avaliada a aplicação de um processo oxidativo avançado após o tratamento convencional do efluente, visando degradar os aditivos orgânicos presentes nos efluentes dos banhos de eletrodeposição de níquel brilhante. Um efluente sintético foi tratado pelo processo físico-químico de coagulação para a remoção do níquel. A amostra foi, então, submetida a testes de ecotoxicidade e, em seguida, o efluente foi tratado pelo processo de fotoeletrooxidação (FEO). A influência da densidade de corrente e o tempo de tratamento foram avaliados. Foi verificada uma redução de carbono orgânico total superior a 38%. Os ensaios de ecotoxicidade para o efluente tratado por fotoeletroxidação indicaram que a FEO degradou parcialmente os aditivos orgânicos e reduziu a concentração que provoca efeitos tóxicos para os organismos teste.

Degradation of cyanotoxins (microcystin) in drinking water using photoelectrooxidation / Degradação de cianotoxinas (microcistinas) em água potável aplicando fotoeletrooxidação

The discharge of sewage and industrial effluents containing high concentrations of pollutants in water bodies increases eutrophication. Cyanobacteria, some of the organisms whose growth is promoted by high nutrient concentrations, are resistant and produce several types of toxins, known as cyanotoxins, highly harmful to human beings. Current water treatment systems for the public water supply are not efficient in degradation of toxins. Advanced oxidation processes (AOP) have been tested for the removal of cyanotoxins, and the results have been positive. This study examines the application of photoelectrooxidation in the degradation of cyanotoxins (microcystins). The performance of the oxidative processes involved was evaluated separately: Photocatalysis, Electrolysis and Photoelectrooxidation. Results showed that the electrical current and UV radiation were directly associated with toxin degradation. The PEO system is efficient in removing cyanotoxins, and the reduction rate reached 99%. The final concentration of toxin was less than 1 µg/L of microcystin in the treated solution.

A descarga de esgotos e efluentes industriais contendo altas concentrações de poluentes nos corpos d'água aumenta a eutrofização. As cianobactérias, são organismos cujo crescimento é promovido por concentrações elevadas de nutrientes, são resistentes e produzem vários tipos de toxinas conhecidas, como cianotoxinas, altamente prejudiciais para os seres humanos. Os sistemas atuais de tratamento de água para o abastecimento público de água não são eficientes na degradação destas toxinas. Processos oxidativos avançados (POA) foram testados para a remoção de cianotoxinas, e os resultados têm sido positivos. Este estudo avalia o processo de fotoeletrooxidação (FEO) na degradação de cianotoxinas (microcistinas). Foi avaliado o desempenho dos processos envolvidos separadamente: fotocatalisis, eletrólise e fotoeletrooxidação. Os resultados mostram que a potencia da radiação UV e da corrente elétrica estão diretamente associados com a degradação de toxinas. O sistema de FEO é eficiente na remoção de cianotoxinas e a redução foi de 99%. A concentração final de toxina foi inferior a 1 g / L de microcistina na solução tratada.

[Studying the accelerated photostability of ciprofloxacin and lomefloxacin in tablets and eye drops]

In this work the photostability of two fluoroquinolones: ciprofloxacin and lomefloxacin has been detected in tables and eye drops formulations using light-stability cabinet. Ciprofloxacin and lomefloxacin were subjected to stress conditions. The degradation products were well separated from the peak of the active substance. The stability of these compounds has been studied both in containers and under direct light in the light-stability cabinet. Samples were assayed immediately and at 1,3,6 months by stability-indicating high performance liquid chromatography methods with photodiode array detector. The determination was performed on C18 [250 x4.6mm, 6 micro m]. The first mobile phase consisted of 0.025M phosphoric acid and acetonitrile [87:13] pumped at a flow rate 2ml/min for ciprofloxacin, while the second consisted of water, acetonitrile, triethylamine [80:20:0.3] pumped at a flow rate 1ml/min for lomefloxacin. The UV detector was operated at 278 nm for ciprofloxacin and 288 nm for lomefloxacin. The methods was suitably validated for linearity, accuracy, precision, robustness and selectivity. All validation parameters were within the acceptance range. Data analysis revealed that plastic and amber containers can not protect either ciprofloxacin or lomefloxacin in eye drops formulation from photodegradation after one month in the cabinet. White blister protect the two agents in tablets formulation after six months in the cabinet

HPLC-MS identification of degradation products of levofloxacin / 药学学报

The study aims to identify the degradation products of levofloxacin by HPLC-MS. The degradation products of levofloxacin were chromatographed on Agilent Zorbax Extend-C18 column (250 mm x 4.6 mm, 5 microm). The mobile phase was 0.1% ammonium acetate solution (using methanoic acid to adjust to pH 3.5)-acetonitrile at the flow rate of 0.5 mL x min(-1) (gradient elution), the column temperature was 40 degrees C. Descarboxyl levofloxacin, desmethyl levofloxacin and levofloxacin N-oxide were identified through comparing with the standard spectrum and the results of mass spectrometry, i.e. m/z 318.2 was descarboxyl levofloxacin, m/z 348.2 was desmethyl levofloxacin, m/z 378.1 was levofloxacin-N-oxide. This method is simple, fast, accurate and suitable for the identification of degradation products of levofloxacin.

Bulk-like endocytosis plays an important role in the recycling of insulin granules in pancreatic beta cells

Although bulk endocytosis has been found in a number of neuronal and endocrine cells, the molecular mechanism and physiological function of bulk endocytosis remain elusive. In pancreatic beta cells, we have observed bulk-like endocytosis evoked both by flash photolysis and trains of depolarization. Bulk-like endocytosis is a clathrin-independent process that is facilitated by enhanced extracellular Ca(2+) entry and suppressed by the inhibition of dynamin function. Moreover, defects in bulk-like endocytosis are accompanied by hyperinsulinemia in primary beta cells dissociated from diabetic KKAy mice, which suggests that bulk-like endocytosis plays an important role in maintaining the exo-endocytosis balance and beta cell secretory capability.

Fate and Transport of Mercury in Environmental Media and Human Exposure / 예방의학회지

Mercury is emitted to the atmosphere from various natural and anthropogenic sources, and degrades with difficulty in the environment. Mercury exists as various species, mainly elemental (Hg0) and divalent (Hg2+) mercury depending on its oxidation states in air and water. Mercury emitted to the atmosphere can be deposited into aqueous environments by wet and dry depositions, and some can be re-emitted into the atmosphere. The deposited mercury species, mainly Hg2+, can react with various organic compounds in water and sediment by biotic reactions mediated by sulfur-reducing bacteria, and abiotic reactions mediated by sunlight photolysis, resulting in conversion into organic mercury such as methylmercury (MeHg). MeHg can be bioaccumulated through the food web in the ecosystem, finally exposing humans who consume fish. For a better understanding of how humans are exposed to mercury in the environment, this review paper summarizes the mechanisms of emission, fate and transport, speciation chemistry, bioaccumulation, levels of contamination in environmental media, and finally exposure assessment of humans.

In vivo photorelease of GABA in the mouse cortex

Electrical stimulation has been used for more than 100 years in neuroscientific and biomedical research as a powerful tool for controlled perturbations of neural activity. Despite quickly driving neuronal activity, this technique presents some important limitations, such as the impossibility to activate or deactivate specific neuronal populations within a single stimulation site. This problem can be avoided by pharmacological methods based on the administration of receptor ligands able to cause specific changes in neuronal activity. However, intracerebral injections of neuroactive molecules inherently confound the dynamics of drug diffusion with receptor activation. Caged compounds have been proposed to circumvent this problem, for spatially and temporally controlled release of molecules. Caged compounds consist of a protecting group and a ligand made inactive by the bond between the two parts. By breaking this bond with light of an appropriate wavelength, the ligand recovers its activity within milliseconds. To test these compounds in vivo, we recorded local field potentials (LFPs) from the cerebral cortex of anesthetized female mice (CF1, 60-70 days, 20-30 g) before and after infusion with caged γ-amino-butyric-acid (GABA). After 30 min, we irradiated the cortical surface with pulses of blue light in order to photorelease the caged GABA and measure its effect on global brain activity. Laser pulses significantly and consistently decreased LFP power in four different frequency bands with a precision of few milliseconds (P < 0.000001); however, the inhibitory effects lasted several minutes (P < 0.0043). The technical difficulties and limitations of neurotransmitter photorelease are presented, and perspectives for future in vivo applications of the method are discussed.

Treatment options for wastewater effluents from pharmaceutical companies

In recent years, concerns about the occurrence and fate of active pharmaceutical ingredients, solvents, intermediates and raw materials that could be present in water and wastewater including pharmaceutical industry wastewater has gained increasing attention. Traditional wastewater treatment methods, such as activated sludge, are not sufficient for the complete removal of active pharmaceutical ingredients and other wastewater constituents from these waters. As a result, complementary treatment methods such as membrane filtration, reverse osmosis and activated carbon are often used in conjunction with the traditional methods for treatment of industrial wastewater. Most of the literature published to date has been on the treatment of municipal wastewater. However, there is a growing body of research that looks at the presence of active pharmaceutical ingredients in industrial wastewater, the treatment of these wastewaters and the removal rates. This article, reviews these treatment methods and includes both traditional methods and advanced oxidation processes. The paper concludes by showing that the problem of pharmaceuticals in wastewaters cannot be solved merely by adopting end of pipe measures. At source measures, such as replacement of critical chemicals, reduction in raw material consumption should continue to be pursued as the top priority

Degradation of common pharmaceutical and personal care products in mixed solutions by advanced oxidation techniques

Widespread detection of pharmaceutical compounds in water environment has been a serious concern recently, while conventional sewage treatments are ineffective for their elimination. But, advanced oxidation techniques are very promising to remove varieties of organic contaminants in water. This research aims to elucidate oxidation potentials of sixteen commonly used pharmaceutical compounds in mixed solutions by seven advanced oxidation techniques in laboratory batch experiments. The removal profiles exhibited four distinct patterns: a] easily degradable by all seven techniques, b] not easily degradable by all seven techniques, c] easily degradable by ozone-based techniques, but not by ultraviolet radiation-based techniques and d] easily degradable by ultraviolet radiation-based techniques, but not by ozone-based techniques. Ozone-based techniques rather than ultraviolet radiation-based techniques were very powerful for simultaneous removal of the compounds efficiently. Moreover, ozonation combined with ultraviolet radiation was the most appropriate technique for simultaneous removal of the tested compounds efficiently. Increased ozone dissolution and decomposition with ozone-based techniques did not always enhance the compounds' removal. Physicochemical properties of the compounds and solution pH also presumably played an important role on the removal which merits further attention

Effectiveness of ultrasound and ultraviolet irradiation on degradation of carbaryl from aqueous solutions

Carbaryl [1-naphthyl-N-methyl carbamate] is a chemical in the carbamate family used chiefly as an insecticide. It is a cholinesterase inhibitor and is toxic to humans and classified as a likely human carcinogen. In the present study, the degradation of the carbaryl pesticide was investigated in the laboratory synthetic samples of tap water, in the effect of sonolysis and photolysis processes. This study was conducted during 2006-7 in Chemistry and Biochemistry of Pesticides Laboratory in Tehran University of Medical Sciences [TUMS] in Iran. The carbaryl [80%] was used for preparing samples. First concentration of all samples were 4 mg/l. Sonochemical examinations in ultrasound reactor was done in two 35, 130 Hz, and 100 w, and three time. Photolysis examinations has done in the effect of 400 w lamp and moderate pressure and 6 time, then the amount of pesticide in the samples has been measured by the High Performance Thin Layer Chromatography [HPTLC] method. The highest degradation in photolysis process after 1 hour in the 35 KHz was 35%, and in the 130 KHz was 63%. Degradation of carbaryl at 130 KHz is higher than 35 KHz at the same time. Carbaryl elimination was increased by arise frequency and exposure time. After 8 min in photolysis, 100% omitting has been showed. Degradation of carbaryl in high frequency ultrasound wavelength was more than low frequency. Degradation of carbaryl in water, combination of high frequency ultrasound wave length and UV irradiation was considerably more effective than ultrasound or ultraviolet irradiation alone

Preparation, characterization, thermal studies, photochemical behaviours and antimicrobial activity of complexes derived from 5-methyl-3-furaldehyde thiosemicarbazone and HG[II] salts of hallo acids

Complexes from of 5-methyl-3-furaldehydethiosemicarbazone [5M3HFTSC] and Hg[II] salts derived from inorganic [HCl] and organic hallo acids [CHCl2COOH or CF3COOH] have been prepared. There chemical structures were characterized using elemental analyses, conductivity spectral measurements, thermogravimetric methods and photochemical behaviours. The thermal studies of such complexes using thermogravimetric analysis [TGA], derivatives thermogravimetry [DrTG] from ambient temperature to 750°C showed three decomposition steps. These studies indicated that the thermal decompositions are not simples. The photolysis of the studied compounds has been carried out in the presence of H2O2. It was found that, the photolysis was enhanced in the presence of H2O2 due to the generation of .OH radicals which are very strong oxidizing agent. Biological activity of theses compounds was tested and screened for their in-vitro antibacterial and antifungal activity. The mixed ligand complexes generally are more active than the binary and free thiosemicarbazne ligand

Reduction of humic substances in water by application of ultrasound waves and ultraviolet irradiation

Humic substances mainly humic acids constitute the major fraction of natural organic matter in water supplies. They play an important role in the formation of harmful disinfection by products. Degradation of humic acids by means of ultraviolet radiation and ultrasonic irradiation processes was investigated in a laboratory-scale batch photoreactor equipped with an 300 W immersed-type medium-pressure mercury vapour lamp and sonoreactor with low frequency [42 kHz] plate type transducer at 170 W of acoustic power with emphasis on the effect of various parameters on degradation efficiency. Experiments were performed at humic acids initial concentrations varying between 2.5-10 mg/L. Oxidation of humic substances has been followed over time by measuring total organic carbon and UV absorbance in 254 nm and 436 nm. Initial results indicated a strong capacity of photolysis for degradation of humic substances. The results also showed that ultrasonic alone cannot be an efficient method for degradation of humic substances in comparison with UV process. The maximum degradation efficiency of humic substances after 90 min of irradiation, however, was only 5.7% and reached a maximum value of 9.5% after 300 min of irradiation. It was found that total organic carbon can be removed effectively by photolysis. It was also found that lower concentrations of humic substances favor the humic substances degradation. Also, the experimental results indicated that the kinetics of ultrasono-oxidation and photo-oxidation processes fit well by pseudo-first order kinetics

Visible light induced photodegradation and phototoxicity of phloxine B and uranine / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To determine the visible light-induced photodegradation kinetics of two xanthene photosensitizers, phloxine B and uranine, in solution and on the surface of silica TLC plates, and to examine the phototoxicity of residues of degradation, which could provide valuable safety data on the two photosensitizers and other xanthene chemicals when applied in the environment.</p><p><b>METHODS</b>UV-Vis absorption during photodegradation was monitored with a Unico 2102 spectrophotometer. Organic content of samples was measured with a Shimadzu TOC 4100. Phototoxicity tests were carried out using Saccharomyces cerevisiae with the methods modified from Daniels.</p><p><b>RESULTS</b>When phloxine B and uranine degraded in solution, their apparent rate constant k was 0.0019 and 0.0027 min(-1), respectively. The total organic carbon (TOC) content decreased by approximately 50% during the 8 h irradiation period, which led to a gradual decrease in phototoxicity of the residues. The photodegradation of photosensitizers on the surface of silica TLC plates was much faster than that in the solution. The apparent rate constant k and the half life of phloxine B were 0.0073 min(-1) and 95 min, respectively.</p><p><b>CONCLUSION</b>Visible light can rapidly induce photodegradation of phloxine B and uranine. The phototoxicity of residues is also decreased. The environmental risk of applications of phloxine B and uranine is minimal.</p>

Energy delivery to eye in phaco-emulsification using Dodick laser photolysis system

Age- related cataract is the main cause of blindness and visual impairment worldwide. Surgery is the only treatment currently available for lens opacity. It is the most frequently performed procedure in ophthalmology. There are many different advantage and disadvantages. Today, ultrasound phaco-emulsification is the most performed method for surgery. One of alternative energy forms is laser photolysis. The aim of this study was to evaluate the mean energy delivery to eye using Dodick laser photolysis for phaco-emulsification. 76 eyes from 76 patients at Aban Eye Clinic in Esfahan were introduced to study. Cataract density was rated preoperatively using lens opacity classification system III [LOCS III] on 0 to +4 density scale. Lenses with +4 nuclear density scales were excluded. Finally 67 eyes were operated with ARC Dodick laser photolysis system throw 2.8 mm clear corneal incision. Delivered energy was recorded. Of 67 patients, 39 [58.2%] were male and 28 [41.8%] were female, and had a mean age of 58.3+12.8 [14-84 years]. There was no statistically significant difference between age of male patients [56.5+12.8] and female patients [60.7+11.9] [p=0.18]. Mean delivered energy to eyes was 4.5+2.6 joules for nucleuses with density of +1, +2 and +3 mean delivered energy was calculated as 3.32+2.60, 3.7+2.59 and 5.7+2.23 joules respectively. Finally it was reverted that there was a direct relationship between delivered energy and nuclear density [p=0.00001, r=0.57]. In spite of the lower amount of energy used, as the preoperative hardness of lens nucleus or lengthening of operation cannot be predicted before surgery, this technique is not well- accepted; hopefully with resolving of technical problems in the future, it can be used more properly

Phenylthiourea derivatives as organic stabilizer for polystyrene against photodegradation

N-phenylthiourea derivatives have been prepared and investigated as photostabilizers for polystyrene by measuring the extent of weight loss [%], the amount of formed gel as well as the average molecular weights of the soluble fractions [M[v]] of the degraded polymers. The results indicated a reasonable stabilizing effect of these derivatives compared with phenyl salicylate UV-absorber. A synergistic effect is achieved when the investigated stabilizers are mixed with the phenyl salicylate in a weight ratio of 25% of the thiourea derivative and 75% of the reference stabilizer. A probable radical mechanism is proposed to account for the stabilizing action of the organic investigated materials

Photo-degradation products of 1-1-(6-methoxy-2-naphthyl)ethyl-2-(4-nitrobenzyl)-6,7-dimethoxyl-1,2,3,4-tetrahydroisoquinoline hydrobromide / 药学学报

To study the photo-degradation products of 1-[1-(6-methoxy-2-naphthyl) ethyl]-2-(4-nitrobenzyl)-6,7-dimethoxyl-1,2,3,4-tetrahydroisoquinoline hydrobromide (code designation: P91024). The chemical structures of the major photo-degradation products of P91024 were identified by HPLC-MS and spectroscopic methods, and their reference substances were also synthesized for confirmation. The three major photo-degradation products were identified to be N-(4-nitrobenzyl)-6,7-dimethoxyl-3, 4-dihydroisoquinoline bromide, 1-[1-(6-methoxyl-2-naphthyl) ethyl]-6, 7-dimethoxyl-1, 2, 3, 4-tetrahydroisoquinoline and 2-isopropyl-6-methoxyl-naphthalene, respectively.