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1.
Bull Environ Contam Toxicol ; 99(1): 100-107, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28289807

RESUMO

The spatio-temporal distribution and the controlling factors of petroleum hydrocarbons (PHCs) in sediments of Chilika lagoon was investigated. Samples were collected during three seasons and quantified using UV-fluorescence spectroscopy. Concentrations of PHCs in surface sediments varies from 0.18 to 12.13 ppm (mean 3.71 ± 3.94 ppm). Compared to the lagoon, the monitoring stations adjacent to jetties with high boating activities tend to have higher PHC concentrations, suggesting that the contribution is likely to be from fossil fuel combustion and accidental seepage. The sediment organic matter (OM) of Chilika ranges from 0.26% to 6.23%. PHC maintains a positive correlation with OM (p < 0.05; f = 0.334), indicating the long term deposition of PHC as sediment OM. However, there is no significant relation between PHC and sediment texture, indicating its negligible control over PHC. The recorded PHC concentrations are below the threshold limit (70 ppm) as classified by United States (US) National Academy of Sciences (NAS) and also lower than those reported from similar ecosystems in India and overseas. Since the long term deposition and the bioaccumulation of PHC cannot be avoided, it is essential to monitor these parameters periodically.


Assuntos
Sedimentos Geológicos/química , Hidrocarbonetos/análise , Petróleo/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Índia , Água do Mar/química
2.
J Synchrotron Radiat ; 20(Pt 4): 531-40, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23765294

RESUMO

Nonlinear optical (NLO) instrumentation has been integrated with synchrotron X-ray diffraction (XRD) for combined single-platform analysis, initially targeting applications for automated crystal centering. Second-harmonic-generation microscopy and two-photon-excited ultraviolet fluorescence microscopy were evaluated for crystal detection and assessed by X-ray raster scanning. Two optical designs were constructed and characterized; one positioned downstream of the sample and one integrated into the upstream optical path of the diffractometer. Both instruments enabled protein crystal identification with integration times between 80 and 150 µs per pixel, representing a ∼10(3)-10(4)-fold reduction in the per-pixel exposure time relative to X-ray raster scanning. Quantitative centering and analysis of phenylalanine hydroxylase from Chromobacterium violaceum cPAH, Trichinella spiralis deubiquitinating enzyme TsUCH37, human κ-opioid receptor complex kOR-T4L produced in lipidic cubic phase (LCP), intimin prepared in LCP, and α-cellulose samples were performed by collecting multiple NLO images. The crystalline samples were characterized by single-crystal diffraction patterns, while α-cellulose was characterized by fiber diffraction. Good agreement was observed between the sample positions identified by NLO and XRD raster measurements for all samples studied.


Assuntos
Microscopia de Fluorescência/métodos , Síncrotrons , Cristalização , Humanos , Proteínas/química , Difração de Raios X
3.
Crit Rev Anal Chem ; : 1-11, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37610291

RESUMO

Sulfur-containing compounds are naturally found in crude oil, and they can be partially removed during the refining process. The wide use of fossil fuels has a significant contribution to sulfur emissions into the atmosphere, and Governments are striving to reduce the amount of the fuels by environmental regulations. The reduction of sulfur levels in diesel and other transportation fuels is beneficial from economic and environmental points, but meeting this standard represents a major operational and economic challenge for the oil and gas industry. Quantitative measurement of the sulfur amount must be taken along the oil refining chains guided by standards of measurement and recommended analytical methods such as various American Society for Testing and Materials methods (ASTM D2622, ASTM D5453, ASTM D7039, and ASTM D7220). Advancement in the refining processes and environmental regulations also require reliable measurements and well-defined criteria for compliance assessment. This work presented a brief review of the ASTM Standards used in the laboratories of the Brazilian oil and gas industry to determine the total sulfur content in fuels. We also presented an approach based on the reproducibility of the measurement methods and the guard band concept to evaluate the conformity statement.

4.
Mar Pollut Bull ; 176: 113417, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35152115

RESUMO

Certain ultra-violet filter (UVF) components of solar creams have negative impacts on coral reefs and have been prohibited in international tourism destinations (i.e., Hawaii, Florida, and Palau) to protect coral reefs. In the Mediterranean coasts which are also hotspots of international tourism and where endemic seagrass Posidonia oceanica forms extensive meadows, the accumulation of UVF components have not been studied. We report for the first time, that the rhizomes of P. oceanica internally accumulated UVFs BP3, BP4, AVO, 4MBC and MeBZT and the paraben preservative MePB. The components BP4 and MePB occurred in higher concentrations reaching up to 129 ng g-1 dw and 512 ng g-1 dw, respectively. This work emphasizes the need for more experimental studies on the effects of UVFs on seagrasses and check if we should follow suit to prohibit certain UVFs to protect this species as what has been done in other regions to protect corals.


Assuntos
Alismatales , Protetores Solares , Florida , Havaí , Mar Mediterrâneo
5.
Herit Sci ; 10(1): 171, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36320569

RESUMO

Daylight fluorescent pigments with their intense color effects have attracted great interest among artists since their market launch in the mid-twentieth century. Since then they have been widely used in the visual arts. The pigments are mainly compositions of organic fluorescent dyes and optical brighteners diluted in an insoluble resin. Due to the susceptibility of the dyes to visible and UV radiation, their lightfastness is comparatively low. This paper presents a comprehensive study of the color and fluorescence changes of daylight fluorescent paints upon exposure in visible light and ultraviolet radiation conducted on mock-ups of commercial daylight fluorescent pigments. The different aging characteristics of the pigments depend on the color tone. They were recorded by means of photographic and colorimetric documentation. In addition, Raman spectroscopy was used to identify the main dyes of the various pigments, even in the complex system of paints, consisting of primer, binder, resin and dyes, and to determine their degradation during aging. Fluorescence spectroscopy revealed that the change in fluorescent color may not only be due to the decrease in dye concentration, but also to the transformation of the original dyes into other fluorescent compounds during light aging. Finally, this paper provides recommendations for the presentation of artworks containing daylight fluorescent pigments. Supplementary Information: The online version contains supplementary material available at 10.1186/s40494-022-00812-4.

6.
Int J Surg Case Rep ; 93: 106946, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35318186

RESUMO

Synthetic sub-urethral sling has become the most widely used technique for the surgical management of stress urinary incontinence. Despite a higher success rate, complications like migration, encrustation, and stone formation have been reported by a mid-urethral sling (MUS). Among mid-urethral sling procedures, mini vaginal tape (MVT) is very popular. As periurethral stone formation and urethrovaginal fistula are very uncommon after MVT, case report on this issue is sparse. The current case report features a 55-year female presented with lower abdominal pain and continuous urinary incontinence, 10 years after the MVT. She was diagnosed as a case of periurethral stone with urinary incontinence due to urethro-vaginal fistula. Our surgical team successfully removed the stone formed by the encrustation of the displaced tape and repaired the fistula. Following the MVT, a high degree of suspicion and long-term follow-up is mandatory for the diagnosis and management of these rare complications.

7.
Transl Androl Urol ; 10(10): 3705-3713, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34804814

RESUMO

BACKGROUND: To describe our initial experience with robotic ureteral reimplantation for the management of ureterovaginal fistulas. METHODS: Between January 2018 and January 2020, four patients received robotic ureteral reimplantation for ureterovaginal fistulas. All patients were diagnosed based on anterograde urography and computed tomography urography (CTU). Follow-up was performed with magnetic resonance urography and renal ultrasound as well as the clinical assessment of symptoms. RESULTS: The mean age of all patients was 50.3 (range, 37-65) years. The cause of the ureterovaginal fistula in four patients was due to a previous hysterectomy. The mean time from fistula diagnosis to robotic repair surgery was 14.5 (range, 3-36) months. All robotic procedures were successfully performed without intraoperative complications or open conversion. The mean operative time was 137 (range, 116-171) minutes, and the mean estimated blood loss was 25 (range, 10-50) mL. No postoperative complications that were high grade (grade III and IV) occurred within one month of surgery. Patients had the double-J (D-J) stents removed 2 months after surgery and the nephrostomy tubes removed 3 months after the operation. There was a 100% success rate without serious complications, such as the leakage of urine and side progressive hydronephrosis, during the 6 to 24 months of follow-up. CONCLUSIONS: Our initial results and experience showed that robotic ureteral reimplantation for the management of ureterovaginal fistula is safe and feasible.

8.
Int J Womens Dermatol ; 7(1): 28-44, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33537394

RESUMO

Sunscreens are topical preparations containing any number of ultraviolet filters (UVFs). The first part of the review will focus on the recent Food and Drug Administration (FDA) regulations of 2019 and general use of these agents. While sunscreen products are becoming more regulated in the United States, we still lag behind other countries in our options for UVFs. Sun protection to prevent skin cancer and aging changes should be a combination of sun avoidance, protective structures, and clothing as well as use of sunscreen products. Newer and safer products are needed to help supplement and replace older agents as well as improve their cosmetic acceptability. This will be a review of ingredients, local toxicities (i.e. contact dermatitis, photocontact dermatitis), special considerations for children, and cosmesis of sunscreen preparations. Part 2 will focus on the environmental, ecological and human toxicities that have been increasingly related to UVFs.

9.
Int J Womens Dermatol ; 7(1): 45-69, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33537395

RESUMO

BACKGROUND: Sunscreens are topical preparations containing one or more compounds that filter, block, reflect, scatter, or absorb ultraviolet (UV) light. Part 2 of this review focuses on the environmental, ecological effects and human toxicities that have been attributed to UV filters. METHODS: Literature review using NIH databases (eg, PubMed and Medline), FDA and EPA databases, Google Scholar, the Federal Register, and the Code of Federal Regulations (CFR). LIMITATIONS: This was a retrospective literature review that involved many different types of studies across a variety of species. Comparison between reports is limited by variations in methodology and criteria for toxicity. CONCLUSIONS: In vivo and in vitro studies on the environmental and biological effects of UV filters show a wide array of unanticipated adverse effects on the environment and exposed organisms. Coral bleaching receives considerable attention from the lay press, but the scientific literature identifies potential toxicities of endocrine, neurologic, neoplastic and developmental pathways. These effects harm a vast array of aquatic and marine biota, while almost no data supports human toxicity at currently used quantities (with the exception of contact allergy). Much of these data are from experimental studies or field observations; more controlled environmental studies and long-term human use data are limited. Several jurisdictions have prohibited specific UV filters, but this does not adequately address the dichotomy of the benefits of photoprotection vs lack of eco-friendly, safe, and FDA-approved alternatives.

10.
Med Clin North Am ; 102(2): 313-324, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29406060

RESUMO

Female voiding dysfunction and incontinence are common in the general population and symptoms have been shown to have a significant negative impact on health-related quality of life. This article highlights the epidemiology, evaluation, diagnosis, pharmacologic therapies, and surgical treatment for overactive bladder, stress urinary incontinence, and urogenital fistulas.


Assuntos
Bexiga Urinária Hiperativa , Incontinência Urinária , Fístula Vaginal , Feminino , Humanos , Bexiga Urinária Hiperativa/complicações , Bexiga Urinária Hiperativa/terapia , Incontinência Urinária/etiologia , Incontinência Urinária/fisiopatologia , Incontinência Urinária/terapia , Fístula Vaginal/complicações , Fístula Vaginal/cirurgia
11.
Arab J Urol ; 13(1): 43-52, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26019978

RESUMO

OBJECTIVE: To assess treatment strategies for seven different scenarios for treating complex pelvic fracture urethral injury (PFUI), categorised as repeat surgery for PFUI, ischaemic bulbar urethral necrosis (BUN), repair in boys and girls aged ⩽12 years, in patients with a recto-urethral fistula, or bladder neck incontinence, or with a double block at the bulbomembranous urethra and bladder neck/prostate region. PATIENTS AND METHODS: We retrospectively reviewed the success rates and surgical procedures of these seven complex scenarios in the repair of PFUI at our institution from 2000 to 2013. RESULTS: In all, >550 PFUI procedures were performed at our centre, and 308 of these patients were classified as having a complex PFUI, with 225 patients available for follow-up. The overall success rates were 81% and 77% for primary and repeat procedures respectively. The overall success rate of those with BUN was 76%, using various methods of novel surgical techniques. Boys aged ⩽12 years with PFUI required a transpubic/abdominal approach 31% of the time, compared to 9% in adults. Young girls with PFUI also required a transpubic/abdominal urethroplasty, with a success rate of 66%. In patients with a recto-urethral fistula the success rate was 90% with attention to proper surgical principles, including a three-stage procedure and appropriate interposition. The treatment of bladder neck incontinence associated with the tear-drop deformity gave a continence rate of 66%. Children with a double block at the bulbomembranous urethra and at the bladder neck-prostate junction were all continent after a one-stage transpubic/abdominal procedure. CONCLUSION: An understanding of complex pelvic fractures and their appropriate management can provide successful outcomes.

12.
Arab J Urol ; 12(2): 97-105, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26019933

RESUMO

BACKGROUND: A vesicovaginal fistula (VVF) is an abnormal fistulous tract between the bladder and vagina, causing continuous loss of urine via the vagina. VVF is a relatively uncommon condition, but there is a drastically higher prevalence in the developing world. Furthermore, iatrogenic postoperative VVF is most common in developed countries, compared to mainly obstetric trauma in developing countries. In this review we focus on the development of current management techniques for VVF. METHODS: Medline was searched to identify articles related to urogenital fistulae, including VVF. Based on these reports we focus on the aetiology, clinical presentation, diagnosis and management of VVF. This in-depth review includes the optimal surgical timing, different surgical approaches (including minimally invasive techniques such as laparoscopic and robotic surgery), recommendations for postoperative care, surgical complications, and the need for further research in the use of robotic surgery to treat this condition. RESULTS: In all, 60 articles were identified and included in this review; eight were related to the aetiology, 12 to diagnosis, and 40 to the management of VVF. A thorough evaluation of VVF is imperative for planning the repair. Although the surgeonís experience typically influences the surgical approach, special situations will dictate the best approach. CONCLUSION: The treatment of genitourinary fistulae with robotic assistance continues to develop, but further research is necessary to fully understand the use of this technology.

13.
Arab J Urol ; 10(4): 414-7, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26558060

RESUMO

BACKGROUND: An iatrogenic ureterovaginal fistula (UVF) can be a consequence of difficult pelvic surgery. The patient must endure a long wait before having major surgery to reconstruct the injured ureter. Reports that address the minimally invasive treatment of UVF are limited, and are reviewed here. We introduce the concept of using a Memokath™ 051 stent (PNN A/S, Hornbaek, Denmark) as a promising minimally invasive approach for UVF. METHODS: We used PubMed, Science Direct, Google and the Cochrane Library to assemble appropriate evidence-based reference reports. The keywords used for the search were: 'Memokath', 'stent'; 'ureterovaginal fistula' and 'ureteral injury'. The review showed 42 relevant articles published up to September 2011. RESULTS: Ureteric stenting consistently stopped the vaginal leak of urine. The long-term results were not encouraging after removing the JJ stents at 3 months after insertion. Most patients had a recurrence of the vaginal leak of urine. The outcome was different with the Memokath stent, that remained in situ for a duration far exceeding that of the JJ stent. The Memokath stopped the vaginal leak of urine with no episodes of urinary tract infection and no evidence of stent migration. CONCLUSION: Long-term ureteric stenting has two advantages, in that it facilitates urine flow through the ureteric strictured segment down to the bladder, and it stops urine leakage along the fistula. It further promotes the resolution of the ureteric stricture and healing of the fistula. A duration of 3 months was inadequate when a JJ stent was used, whereas longer periods are possible with the Memokath stent. The optimum stenting period required for complete healing of a UVF remains to be defined. Long-term Memokath ureteric stenting can be an effective alternative and minimally invasive approach to conventional surgical repair in selected cases.

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