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2.
Annu Rev Chem Biomol Eng ; 7: 135-62, 2016 Jun 07.
Article in English | MEDLINE | ID: mdl-26979411

ABSTRACT

The advent of the industrial revolution in the nineteenth century increased the volume and variety of manufactured goods and enriched the quality of life for society as a whole. However, industrialization was also accompanied by new manufacturing and complex processes that brought about the use of hazardous chemicals and difficult-to-control operating conditions. Moreover, human-process-equipment interaction plus on-the-job learning resulted in further undesirable outcomes and associated consequences. These problems gave rise to many catastrophic process safety incidents that resulted in thousands of fatalities and injuries, losses of property, and environmental damages. These events led eventually to the necessity for a gradual development of a new multidisciplinary field, referred to as process safety. From its inception in the early 1970s to the current state of the art, process safety has come to represent a wide array of issues, including safety culture, process safety management systems, process safety engineering, loss prevention, risk assessment, risk management, and inherently safer technology. Governments and academic/research organizations have kept pace with regulatory programs and research initiatives, respectively. Understanding how major incidents impact regulations and contribute to industrial and academic technology development provides a firm foundation to address new challenges, and to continue applying science and engineering to develop and implement programs to keep hazardous materials within containment. Here the most significant incidents in terms of their impact on regulations and the overall development of the field of process safety are described.


Subject(s)
Safety , Disasters/prevention & control , Humans , Resilience, Psychological , Risk Assessment , Safety Management
3.
Nat Prod Res ; 28(5): 312-7, 2014.
Article in English | MEDLINE | ID: mdl-24304347

ABSTRACT

Aqueous and organic fractions from the crude extracts of 17 sponge species collected at Boca de Calderas, Havana, Cuba were analysed. The organic fractions of Mycale laxissima, Clathria echinata and Agelas cerebrum exhibited values of concentrations causing 50% inhibition of in vitro growth of Plasmodium berghei (IC50) of 42.3 ± 5.1, 52 ± 9.7 and 60.3 ± 10.6 µg/mL, respectively, while their selectivity indexes for fibroblast cell lines were 9.45, 4.24 and 8.7, correspondingly. These fractions reduced parasitemia of infected Balb/c mice as well. Selective cytotoxicity indexes against tumour HeLa cells focused an interest on the aqueous fraction of M. laxissima (>7.12) and organic fractions of Polymastia nigra (5.95), A. cerebrum (5.48) and Niphates erecta (>4.2). Triterpenoids/steroids and alkaloids detected in the organic fractions of M. laxissima, C. echinata and A. cerebrum should be isolated for future investigation.


Subject(s)
Antimalarials/isolation & purification , Antimalarials/pharmacology , Antineoplastic Agents/isolation & purification , Antineoplastic Agents/pharmacology , Porifera/chemistry , Alkaloids/pharmacology , Animals , Antimalarials/chemistry , Antineoplastic Agents/chemistry , Cuba , Drug Screening Assays, Antitumor , HeLa Cells , Humans , Malaria/drug therapy , Mice , Mice, Inbred BALB C , Oceans and Seas , Plasmodium berghei/drug effects , Plasmodium falciparum/drug effects , Steroids/pharmacology , Triterpenes/pharmacology
4.
Article in English | MEDLINE | ID: mdl-22824729

ABSTRACT

Sea anemones are sources of biologically active proteins and peptides. However, up to date few peptidomic studies of these organisms are known; therefore most species and their peptide diversity remain unexplored. Contrasting to previous venom peptidomic works on sea anemones and other venomous animals, in the present study we combined pH gradient ion-exchange chromatography with gel filtration and reversed-phase chromatography, allowing the separation of the 1-10 kDa polypeptides from the secretion of the unexplored sea anemone Phymanthus crucifer (Cnidaria/Phymanthidae). This multidimensional chromatographic approach followed by MALDI-TOF-MS detection generated a peptide fingerprint comprising 504 different molecular mass values from acidic and basic peptides, being the largest number estimated for a sea anemone exudate. The peptide population within the 2.0-3.5 kDa mass range showed the highest frequency whereas the main biomarkers comprised acidic and basic peptides with molecular masses within 2.5-6.9 kDa, in contrast to the homogeneous group of 4-5 kDa biomarkers found in sea anemones such as B. granulifera and B. cangicum (Cnidaria/Actiniidae). Our study shows that sea anemone peptide fingerprinting can be greatly improved by including pH gradient ion-exchange chromatography into the multidimensional separation approach, complemented by MALDI-TOF-MS detection. This strategy allowed us to find the most abundant and unprecedented diversity of secreted components from a sea anemone exudate, indicating that the search for novel biologically active peptides from these organisms has much greater potential than previously predicted.


Subject(s)
Chromatography, Ion Exchange/methods , Peptide Mapping/methods , Peptides/analysis , Peptides/chemistry , Sea Anemones/metabolism , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Animals , Chromatography, Gel , Hydrogen-Ion Concentration , Hydrophobic and Hydrophilic Interactions , Marine Toxins/analysis , Marine Toxins/chemistry , Molecular Weight
5.
Nat Prod Commun ; 7(1): 47-50, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22428242

ABSTRACT

The aqueous ethanol extract of Thalassia testudinum leaves (BM-21) is now being developed in Cuba as an herbal medicine due to its promising pharmacological properties. Although some interesting biological activities of BM-21 have already been reported, its chemical composition remains mostly unknown. Thus, we now describe the qualitative and quantitative analyzes of BM-21 using standard phytochemical screening techniques, including colorimetric quantification, TLC and HPLC analyses. Phytochemical investigation of BM-21 resulted in the isolation and identification of a new phenolic sulfate ester (1), along with ten previously described phenolic derivatives (2-11), seven of which have never been previously reported from the genus Thalassia. The structures of these compounds were established by analysis of their spectroscopic (1D and 2D NMR) and spectrometric (HRMS) data, as well as by comparison of these with those reported in the literature. Furthermore, BM-21 was found to exhibit strong antioxidant activity in four different free radical scavenging assays (HO*, RO2*, O2-* and DPPH*). Consequently, this is the first study which highlights the phytochemical composition of BM-21 and demonstrates that this product is a rich source of natural antioxidants with potential applications in pharmaceutical, cosmetic and food industries.


Subject(s)
Antioxidants/pharmacology , Hydrocharitaceae/chemistry , Plant Extracts/pharmacology , Polyphenols/pharmacology
6.
Mar Biotechnol (NY) ; 11(1): 74-80, 2009.
Article in English | MEDLINE | ID: mdl-18607659

ABSTRACT

Daily topical application of the aqueous ethanolic extract of the marine sea grass, Thalassia testudinum, on mice skin exposed to UVB radiation resulted in a dose-dependent recovery of the skin macroscopic alterations over a 6-day period. Maximal effect (90%) occurred at a dose of 240 microg/cm(2), with no additional effects at higher doses. Bioassay-guided fractionation of the plant extract resulted in the isolation of thalassiolin B (1). Topical application of 1 (240 microg/cm(2)) markedly reduces skin UVB-induced damage. In addition, thalassiolin B scavenged 2,2-diphenyl-2-picrylhydrazyl radical with an EC(50) = 100 microg/ml. These results suggest that thalassiolin B is responsible for the skin-regenerating effects of the crude extract of T. testudinum.


Subject(s)
Antioxidants/pharmacology , Flavonoids/pharmacology , Hydrocharitaceae/chemistry , Skin/drug effects , Skin/radiation effects , Ultraviolet Rays/adverse effects , Animals , Antioxidants/chemistry , Dose-Response Relationship, Drug , Flavonoids/chemistry , Male , Mice , Mice, Inbred BALB C , Molecular Structure , Radiation Injuries, Experimental/drug therapy , Skin/pathology
7.
Rev. otorrinolaringol. cir. cabeza cuello ; 53(2): 83-91, ago. 1993. tab, ilus
Article in Spanish | LILACS | ID: lil-131703

ABSTRACT

Se analiza la erigmofonación como método de rehabilitación vocal por excelencia en pacientes laringectomizados totales entre los años 1988-1990 obteniéndose datos en 61 del total de 71 pacientes operados rehabilitados. La edad promedio fue de 61 años, predominando el sexo masculino con un 83,6 por ciento (51 pacientes). Los resultados obtenidos se clasifican según el siguiente parámetro: buen resultado: habla fluído, inteligible, volumen adecuado. Regular resultado: habla pero con esfuerzo y lentitud, cuesta entender. Mal resultado: no logra hablar. Abandonan el tratamiento fonatorio el 60,7 por ciento de los pacientes por diversas causas. El grupo de pacientes que logra completar la rehabilitación obtiene buenos resultados en el 96 por ciento


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Speech Disorders/rehabilitation , Laryngectomy/rehabilitation , Phonation , Speech Intelligibility , Laryngectomy/adverse effects
8.
Rev. cuba. hig. epidemiol ; 25(4): 371-82, oct.-dic. 1987. ilus, tab
Article in Spanish | CUMED | ID: cum-2107

ABSTRACT

Se incorporan a la investigación 16 sujetos que desde hace varios años participan en la zafra, en el corte de caña de forma manual en contingentes de alta productividad. Se realizan las pruebas ergométricas en posición de sentados sobre una bicicleta Monark y parados, con una bicicleta ergométrica Universal de la firma Mijnhardt, adaptable al trabajo en esta posición. Se informa que en ambos casos se realizan incrementos en la intensidad de la carga hasta que los sujetos son incapaces de mantener las 60 rev/min establecidas para las pruebas. Se recoge el aire espirado en sacos de Douglas y es analizado su contenido en gases, para determinar el consumo máximo de oxígeno. Se registra la frecuencia cardíaca por electrocardiografía. Se aplica la prueba de la t de Student para las observaciones apareadas, con el fin de comprobar la significación estadística entre la frecuencia cardíaca, el consumo de oxígeno, el pulso de oxígeno y el volumen espirado de aire. Se encuentran diferencias significativas para p < 0,01 en todas estas variables, con excepción de la frecuencia cardíaca que presentó, en ambas modalidades de ejercicio, valores similares. Se analizan los posibles factores que provocan la variación en el respuesta fisiológica observada en ambos tipos de trabajo


Subject(s)
Adolescent , Adult , Middle Aged , Humans , Male , Oxygen Consumption , Occupational Medicine , Exercise Test
9.
Rev. cuba. hig. epidemiol ; 25(4): 371-82, oct.-dic. 1987. ilus, tab
Article in Spanish | LILACS | ID: lil-53208

ABSTRACT

Se incorporan a la investigación 16 sujetos que desde hace varios años participan en la zafra, en el corte de caña de forma manual en contingentes de alta productividad. Se realizan las pruebas ergométricas en posición de sentados sobre una bicicleta Monark y parados, con una bicicleta ergométrica Universal de la firma Mijnhardt, adaptable al trabajo en esta posición. Se informa que en ambos casos se realizan incrementos en la intensidad de la carga hasta que los sujetos son incapaces de mantener las 60 rev/min establecidas para las pruebas. Se recoge el aire espirado en sacos de Douglas y es analizado su contenido en gases, para determinar el consumo máximo de oxígeno. Se registra la frecuencia cardíaca por electrocardiografía. Se aplica la prueba de la t de Student para las observaciones apareadas, con el fin de comprobar la significación estadística entre la frecuencia cardíaca, el consumo de oxígeno, el pulso de oxígeno y el volumen espirado de aire. Se encuentran diferencias significativas para p < 0,01 en todas estas variables, con excepción de la frecuencia cardíaca que presentó, en ambas modalidades de ejercicio, valores similares. Se analizan los posibles factores que provocan la variación en el respuesta fisiológica observada en ambos tipos de trabajo


Subject(s)
Adolescent , Adult , Middle Aged , Humans , Male , Exercise Test , Occupational Medicine , Oxygen Consumption
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