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1.
J Chromatogr Sci ; 59(3): 205-211, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33275654

RESUMEN

An ionic liquid (IL) 111 column was compared with other commonly employed stationary phases including polydimethyl siloxane and polyethylene glycol for the separation of fatty acid monomethyl and dimethyl esters. The fatty acid esters employed in this study were derived from metathesis reactions of vegetable oils both with and without olefins. The IL 111 column demonstrated enhanced performance compared with conventional columns for the separation of these esters. These advantages included significantly enhanced retention of dimethyl esters relative to monomethyl esters, excellent cis/trans isomer separation and the ability to analyze higher carbon number dimethyl esters. As a result, these columns are highly suited for the analysis of mixtures of mono- and dimethyl fatty acid esters found in lipid metathesis reaction products or to determine monofunctional impurities in samples of commercial dimethyl esters.


Asunto(s)
Cromatografía de Gases/métodos , Ácidos Grasos/aislamiento & purificación , Líquidos Iónicos/química , Ésteres/análisis , Ésteres/química , Ésteres/aislamiento & purificación , Ácidos Grasos/análisis , Ácidos Grasos/química , Aceites de Plantas/química
2.
Sex Med ; 4(3): e176-81, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27033339

RESUMEN

INTRODUCTION: Female sexual dysfunction affects up to 43% of women in the United States and hypoactive sexual desire disorder (HSDD) is the most common type; however, we lack treatment options showing improvement for this condition. AIMS: To investigate whether acupuncture therapy could improve HSDD. METHODS: Premenopausal women with a primary diagnosis of HSDD were included in a single-arm prospective pilot study that was approved by the institutional review board. After providing informed consent, subjects completed validated questionnaires. Participants underwent 25-minute twice-weekly acupuncture sessions for 5 weeks with one certified acupuncturist. Questionnaires were completed again 6 weeks after onset of treatment. MAIN OUTCOME MEASURES: Based on a statistically significant change in the desire domain of the Female Sexual Function Index from 2.0 (at baseline) to 2.4 (after intervention with a specialist) in our population of patients diagnosed with HSDD, a sample of 13 was determined, with 90% power and α 0.05. RESULTS: Fifteen women were enrolled and 13 completed the study. Mean age was 36.9 ± 11.4 years. Most were white (n = 9, 60%), heterosexual (n = 15, 100%), and non-smokers (n = 14, 93%). Most were sexually active more than four times per month (n = 8, 53%) and none had a history of sexual abuse (n = 15, 100%). Participants received a mean acupuncture needle application of 17 ± 2 at each session. Sexual function improved after intervention, particularly desire (2.1 ± 0.6 to 3.3 ± 1.2, P < .0001), arousal (P < .0001), lubrication (P = .03), and orgasm (P = .005). CONCLUSION: In this cohort of premenopausal women with HSDD, 5 weeks of acupuncture therapy was associated with significant improvements in sexual function, particularly desire. This supports a role for acupuncture as a therapeutic option for women with low desire.

3.
Int Urogynecol J ; 24(7): 1091-103, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23632798

RESUMEN

INTRODUCTION AND HYPOTHESIS: The objective of this study was to create a valid, reliable, and responsive sexual function measure in women with pelvic floor disorders (PFDs) for both sexually active (SA) and inactive (NSA) women. METHODS: Expert review identified concept gaps and generated items evaluated with cognitive interviews. Women underwent Pelvic Organ Prolapse Quantification (POPQ) exams and completed the Incontinence Severity Index (ISI), a prolapse question from the Epidemiology of Prolapse and Incontinence Questionnaire (ISI scores), the Pelvic Floor Distress Inventory-20 (PFDI-20), and the Female Sexual Function Index (FSFI). Principle components and orthogonal varimax rotation and principle factor analysis with oblique rotation identified item grouping. Cronbach's alpha measured internal consistency. Factor correlations evaluated criterion validation. Change scores compared to change scores in other measures evaluated responsiveness among women who underwent surgery. RESULTS: A total of 589 women gave baseline data, 200 returned surveys after treatment, and 147 provided test-retest data. For SA women, 3 subscales each in 2 domains (21 items) and for NSA women 2 subscales in each of 2 domains (12 items) emerged with robust psychometric properties. Cronbach's alpha ranged from .63 to .91. For SA women, correlations were in the anticipated direction with PFDI-20, ISI, and FSFI scores, POPQ, and EPIQ question #35 (all p < .05). PFDI-20, ISI, and FSFI subscale change scores correlated with Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire International Urogynecological Association-revised (PISQ-IR) factor change scores and with mean change scores in women who underwent surgery (all p < .05). For NSA women, PISQ-IR scores correlated with PFDI-20, ISI scores, and with EPIQ question #35 (all p < .05). No items demonstrated differences between test and retest (all p ≥ .05), indicating stability over time. CONCLUSIONS: The PISQ-IR is a valid, reliable, and responsive measure of sexual function.


Asunto(s)
Trastornos del Suelo Pélvico/complicaciones , Prolapso de Órgano Pélvico/complicaciones , Disfunciones Sexuales Fisiológicas/diagnóstico , Adulto , Anciano , Femenino , Humanos , Persona de Mediana Edad , Psicometría , Reproducibilidad de los Resultados , Disfunciones Sexuales Fisiológicas/etiología , Encuestas y Cuestionarios
4.
J Chromatogr Sci ; 49(5): 370-4, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21549028

RESUMEN

A high-speed gas chromatographic method has been developed to determine the FAME distribution of B100 biodiesel. The capillary column used in this work has dimensions of 20 m × 0.100 mm and is coated with a polyethylene glycol film. Analysis times are typically on the order of 4-5 min depending upon the composition of the B100. The application of this method to a variety of vegetable and animal derived B100 is demonstrated. Quantitative results obtained with this method were in close agreement with those obtained by a more conventional approach on a 100 m column. The method, coupled with solid-phase extraction, was also found suitable to determine the B100 content of biodiesel-diesel blends.


Asunto(s)
Biocombustibles/análisis , Cromatografía de Gases/métodos , Ácidos Grasos/aislamiento & purificación , Ácidos Grasos/análisis , Reproducibilidad de los Resultados , Extracción en Fase Sólida
5.
J Chromatogr Sci ; 49(5): 384-96, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21549031

RESUMEN

This review surveys chromatographic technology that has been applied to the characterization of biodiesel and its blends. Typically, biodiesel consists of fatty acid methyl esters produced by transesterification of plant or animal derived triacylglycerols. Primary attention is given to the determination of trace impurities in biodiesel, such as methanol, glycerol, mono-, di-, and triacylglycerols, and sterol glucosides. The determination of the fatty acid methyl esters, trace impurities in biodiesel, and the determination of the biodiesel content of commercial blends of biodiesel in conventional diesel are also addressed.


Asunto(s)
Biocombustibles , Cromatografía/métodos , Ácidos Grasos/química , Glicerol/química , Metanol/química
6.
J Chromatogr Sci ; 48(4): 283-8, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20412650

RESUMEN

Several years ago, the presence of elemental sulfur in gasoline became a significant issue for the automotive and fuel industries. In several incidents, elemental sulfur at trace levels led to the corrosion of silver alloy fuel sensing elements in automobile gasoline tanks. This report describes a derivatization method that allows the determination of trace levels of elemental sulfur using flame ionization detection. The sample is derivatized with triphenylphosphine to form triphenylphosphine sulfide. This component is readily detected with a flame ionization detector. In most analyses, on-column injection was employed to allow detection of trace levels of elemental sulfur. However some analyses with splitless injection were also performed. For some gasolines, detection limits on the order of less than 1 microg/g elemental sulfur were possible with this approach. However, the detection limit can vary depending upon the concentration of trace higher boiling components. The precision of the analysis, as measured by the relative standard deviation of triplicate injections, for gasolines containing 1 to 10 microg/g of elemental sulfur was in the 1 to 3% range. The recovery of a gasoline spiked with approximately 4 microg/g elemental sulfur was 102%. The presence of ethanol did not appear to affect results.

7.
Int J Impot Res ; 22(2): 105-14, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20072131

RESUMEN

Sexual function is complex and involves interaction of many factors, including emotional connection, body image, intact physical response and partner sexual function. Disease processes such as abnormal uterine bleeding, endometriosis, urinary incontinence and pelvic organ prolapse may have a negative impact on various parameters of sexual health. Gynecological surgery to address these common complaints may correct the pathological process. However, despite improvements in symptoms related to the disease, improvements in sexuality are not guaranteed and occasionally there may be deteriorations. This review will summarize the current literature assessing sexual symptoms following benign gynecological surgery, including hysterectomy, and bilateral salpingo-oophorectomy, tubal ligation, anti-incontinence surgery and pelvic organ prolapse reconstruction with and without mesh. In the majority of cases, sexual function and quality of life benefit from these surgical interventions. However, it is critical that physicians remain aware of the potential for negative outcomes. Subjects who experience worsening should undergo thorough evaluation early in the postoperative period in order to mitigate symptoms. Treatment modalities for sexual dysfunction following surgery should be the focus of future research.


Asunto(s)
Procedimientos Quirúrgicos Ginecológicos/efectos adversos , Disfunciones Sexuales Fisiológicas/etiología , Disfunciones Sexuales Psicológicas/etiología , Trompas Uterinas/cirugía , Femenino , Humanos , Histerectomía/efectos adversos , Histerectomía/métodos , Ovariectomía/efectos adversos , Prolapso de Órgano Pélvico/cirugía , Esterilización Tubaria/efectos adversos , Incontinencia Urinaria/cirugía
8.
Minerva Urol Nefrol ; 60(2): 113-22, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18500226

RESUMEN

Stress urinary incontinence is a bothersome condition that may impact quality of life and lead to sexual disorders. However, while surgical repair significantly reduces incontinence, improvements in sexual symptoms are not guaranteed. Vaginal narrowing, diminished orgasm, pain, mesh erosion or decreased lubrication may occur following a small proportion of these interventions. It is important to counsel patients regarding their sexual function and expectations prior to and following any surgical procedure in order to mitigate any negative impact on their overall quality of life.


Asunto(s)
Sexualidad , Incontinencia Urinaria de Esfuerzo/cirugía , Femenino , Humanos , Complicaciones Posoperatorias/etiología , Estudios Prospectivos , Estudios Retrospectivos , Procedimientos Quirúrgicos Urológicos/efectos adversos , Procedimientos Quirúrgicos Urológicos/métodos , Prolapso Uterino/cirugía
9.
Int Urogynecol J Pelvic Floor Dysfunct ; 18(7): 807-12, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17120172

RESUMEN

The purpose of this study is to compare the feasibility of local anesthesia with IV sedation versus general anesthesia for vaginal correction of pelvic organ prolapse. Patients with pelvic organ prolapse who were scheduled for an anterior or posterior colporrhaphy, or an obliterative procedure, and who did not have a contraindication or preference to type of anesthesia were randomized to one of the two anesthesia groups. Nineteen patients were randomized to the general group and 21 patients were randomized to the local group. Mean operating room, anesthesia, and surgical time were similar in each group, and 10 patients in the local group bypassed the recovery room. Requests and doses of antiemetics, postoperative verbal numerical pain scores and length of hospital stay were similar between the two groups. Mean recovery room and total hospital costs were significantly lower in the local group. Local anesthesia with IV sedation is a feasible alternative for vaginal surgery to correct pelvic organ prolapse.


Asunto(s)
Anestésicos Locales , Hipnóticos y Sedantes/administración & dosificación , Dolor Postoperatorio/etiología , Prolapso Uterino/cirugía , Vagina/cirugía , Anciano , Analgésicos/administración & dosificación , Anestesia General/economía , Anestésicos Locales/economía , Antieméticos/administración & dosificación , Femenino , Humanos , Inyecciones Intravenosas , Tiempo de Internación/economía , Tiempo de Internación/estadística & datos numéricos , Persona de Mediana Edad , Quirófanos/estadística & datos numéricos , Náusea y Vómito Posoperatorios/etiología , Periodo Posoperatorio , Sala de Recuperación/estadística & datos numéricos
10.
Int J Syst Evol Microbiol ; 54(Pt 5): 1543-1551, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15388708

RESUMEN

A group of pigmented, slowly growing mycobacteria identified by 16S rRNA gene sequencing as 'MCRO 33' (GenBank accession no. AF152559) have been isolated from several clinical specimens in various laboratories across Canada. Genotypically, the organism is most closely related to Mycobacterium simiae. However, it presents with a similar phenotypic profile to Mycobacterium scrofulaceum. Several reference strains obtained from ATCC and TMC culture collections, previously identified as M. scrofulaceum or M. simiae, have also been found to possess the MCRO 33 16S rRNA gene sequence. Biochemical testing, susceptibility testing, HPLC, hsp65 gene and 16S-23S spacer (ITS1) sequencing were performed on clinical and reference strains to characterize further this unique species. Of the clinical strains, one was isolated from a cervix biopsy whereas all other clinical isolates were obtained from respiratory samples. In one patient, symptoms, imaging and repeat clinical specimens positive on culture for this organism were suggestive of active clinical disease. The description of this species, for which the name Mycobacterium parascrofulaceum sp. nov. is proposed, follows the present trend of a large number of novel Mycobacterium species identified due in great part to sequence-based methods. The type strain is HSC68T (= ATCC BAA-614T = DSM 44648T).


Asunto(s)
Infecciones por Mycobacterium/microbiología , Micobacterias no Tuberculosas/clasificación , Micobacterias no Tuberculosas/aislamiento & purificación , Adulto , Anciano , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Técnicas de Tipificación Bacteriana , Líquido del Lavado Bronquioalveolar/microbiología , Canadá , Cuello del Útero/microbiología , Chaperonina 60 , Chaperoninas/genética , ADN Bacteriano/química , ADN Bacteriano/aislamiento & purificación , ADN Ribosómico/química , ADN Ribosómico/aislamiento & purificación , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/aislamiento & purificación , Femenino , Genes de ARNr , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Datos de Secuencia Molecular , Mycobacterium scrofulaceum/clasificación , Ácidos Micólicos/análisis , Micobacterias no Tuberculosas/genética , Micobacterias no Tuberculosas/fisiología , Filogenia , ARN Bacteriano/genética , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Esputo/microbiología
11.
Biochemistry ; 39(19): 5868-75, 2000 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-10801338

RESUMEN

Catalase-peroxidases have a predominant catalatic activity but differ from monofunctional catalases in exhibiting a substantial peroxidatic reaction which has been implicated in the activation of the antitubercular drug isoniazid in Mycobacterium tuberculosis. Hydroperoxidase I of Escherichia coli encoded by katG is a catalase-peroxidase, and residues in its putative active site have been the target of a site directed-mutagenesis study. Variants of residues R102 and H106, on the distal side of the heme, and H267, the proximal side ligand, were constructed, all of which substantially reduced the catalatic activity and, to a lesser extent, the peroxidatic activity. In addition, the heme content of the variants was reduced relative to the wild-type enzyme. The relative ease of heme loss from HPI and a mixture of tetrameric enzymes with 2, 3, and 4 hemes was revealed by mass spectrometry analysis. Conversion of W105 to either an aromatic (F) or aliphatic (I) residue caused a 4-5-fold increase in peroxidatic activity, coupled with a >99% inhibition of catalatic activity. The peroxidatic-to-catalatic ratio of the W105F variant was increased 2800-fold such that compound I could be identified by both electronic and EPR spectroscopy as being similar to the porphyrin cation radical formed in other catalases and peroxidases. Compound I, when generated by a single addition of H(2)O(2), decayed back to the native or resting state within 1 min. When H(2)O(2) was generated enzymatically in situ at low levels, active compound I was evident for up to 2 h. However, such prolonged treatment resulted in conversion of compound I to a reversibly inactivated and, eventually, to an irreversibly inactivated species, both of which were spectrally similar to compound I.


Asunto(s)
Catalasa/química , Catalasa/genética , Proteínas de Escherichia coli , Escherichia coli/enzimología , Mutagénesis Sitio-Dirigida , Peroxidasas/química , Peroxidasas/genética , Sustitución de Aminoácidos/genética , Proteínas Bacterianas , Sitios de Unión/genética , Catalasa/antagonistas & inhibidores , Catálisis , Espectroscopía de Resonancia por Spin del Electrón , Activación Enzimática/genética , Inhibidores Enzimáticos/farmacología , Escherichia coli/genética , Hemo/química , Leucina/genética , Espectrometría de Masas , Peroxidasas/antagonistas & inhibidores , Fenilalanina/genética , Proteínas Recombinantes/química , Especificidad por Sustrato/genética , Triptófano/genética
12.
Plant Physiol ; 99(2): 665-71, 1992 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16668938

RESUMEN

Addition of l-[U-(14)C]glutamate to a suspension of mechanically isolated asparagus (Asparagus sprengeri Regel) mesophyll cells results in (a) alkalinization of the medium, (b) uptake of l-[U-(14)C]glutamate, and (c) efflux of [(14)C]4-aminobutyrate, a product of glutamate decarboxylation. All three phenomena were eliminated by treatment with 1 millimolar aminooxyacetate. In vitro glutamate decarboxylase (GAD) assays showed that (a) 2 millimolar aminooxyacetate eliminated enzyme activity, (b) activity was pyridoxal phosphate-dependent, and (c) activity exhibited a sharp pH optimum at 6.0 that decreased to 20% of optimal activity at pH 5.0 and 7.0. Addition of 1.5 millimolar sodium butyrate or sodium acetate to cell suspensions caused immediate alkalinization of the medium followed by a resumption of acidification of the medium at a rate approximately double the initial rate. The data indicate that (a) continued H(+)/l-glutamate contransport is dependent upon GAD activity, (b) the pH-dependent properties of GAD are consistent with a role in a metabolic pH-stat, and (c) the regulation of intracellular pH during H(+)/l-Glu symport may involve both H(+) consumption during 4-aminobutyrate production and ATP-driven H(+) efflux.

13.
Anticancer Res ; 10(4): 929-34, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2382990

RESUMEN

Mechanisms of tumor growth are concerned with the possibility that neoplasms are disturbed in their response to growth factors. Interleukin 2 (IL 2) is secreted by activated T-cells and is required for autocrine T-cell growth. Controversy exists as to the functional capacity of T-lymphocytes in patients with B-cell chronic lymphocytic leukemia (CLL). We studied 14 patients with previously untreated, early CLL. Data were compared to 16 healthy individuals. Immunophenotyping showed that T-cells in B-CLL are highly activated as evidenced by HLA-DR and IL 2 receptor expression. Membrane receptors for IL 2 on the patients' T-cells were overexpressed. The T4:T8 ratio was 1.5. T-cells for in vitro studies were isolated by their ability to form E-rosettes with AET and repeated Ficoll density gradient centrifugation. Purified T-cells were grown on semisolid agar and their capability to form colonies investigated using a variety of exogenous stimulants. It was found that patients with CLL showed a pronounced impairment in forming T-cell colonies. However, colony formation was restored to normal by adding exogenous recombinant IL 2, indicating that endogenous IL 2 production of T-cells is deficient. This finding might have implications for the therapeutical use of IL 2 in CLL patients.


Asunto(s)
Interleucina-2/farmacología , Leucemia Linfocítica Crónica de Células B/inmunología , Linfocitos T/inmunología , Anciano , Anciano de 80 o más Años , Femenino , Antígenos HLA-DR/análisis , Humanos , Técnicas In Vitro , Masculino , Persona de Mediana Edad , Fenotipo , Receptores de Interleucina-2/análisis
14.
J Clin Chem Clin Biochem ; 23(11): 765-75, 1985 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-4086981

RESUMEN

Analytical flow cytometers which are easy to operate, and monoclonal antibodies specific for cell surface determinants of lymphocytes, offer a simple and rapid method for the identification of the immunological phenotype of lymphocyte subsets. We investigated mononuclear cells isolated from EDTA-blood bv density gradient centrifugation. The intraassay precision (n = 12) of the determination by means of monoclonal antibodies directed against T-cells (Leu 4), T-helper/inducer-cells (Leu 3 a, b), T-suppressor/cytotoxic cells (Leu 2 a) and cells of the 'NK'-phenotype (Leu 7) varied between 2.2 and 7.9%. Studies using the subset markers Leu 2a and Leu 3a, b conjugated either to fluorescein isothiocyanate (FITC) or to phycoerythrin (PE) showed comparable results for both subsets. Dual immunofluorescent analysis using two different antibodies conjugated to contrasting fluorochromes resulted in slightly higher fractions of T-helper/inducer-cells (Leu 3a, b-FITC: a = 0.97, b = 3.18, r = 0.98) and T-suppressor/cytotoxic cells (Leu 2 a-PE: a = 0.99, b = 2.22, r = 0.97) compared with single immunofluorescent analysis. We found no constant association to explain this statistically significant discrepancy (p less than or equal to 0.0002). The investigation of 100 controls established the following reference values for the fraction of lymphocyte subsets (median, 95%-interval): T-cells 0.75 (0.57-0.87), T-helper/inducer-cells 0.47 (0.34-0.63), T-suppressor/cytotoxic cells 0.26 (0.15-0.42), 'NK'-cells 0.16 (0.04-0.34). The corresponding absolute numbers of cells are: T-cells 1.300 (0.730-2.240), T-helper/inducer-cells 0.820 (0.44-1.540), T-suppressor/cytotoxic cells 0.450 (0.190-0.915), 'NK'-cells 0.300 (0.060-0.670).


Asunto(s)
Linfocitos/clasificación , Adulto , Anticuerpos Monoclonales , Estudios de Evaluación como Asunto , Femenino , Citometría de Flujo , Humanos , Masculino , Persona de Mediana Edad , Fenotipo , Valores de Referencia
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