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1.
Anaesthesia ; 78(10): 1272-1284, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37531294

RESUMEN

International recommendations encourage liberal administration of oxygen to patients having surgery under general anaesthesia, ostensibly to reduce surgical site infection. However, the optimal oxygen regimen to minimise postoperative complications and enhance recovery from surgery remains uncertain. The hospital operating theatre randomised oxygen (HOT-ROX) trial is a multicentre, patient- and assessor-blinded, parallel-group, randomised clinical trial designed to assess the effect of a restricted, standard care, or liberal peri-operative oxygen therapy regimen on days alive and at home after surgery in adults undergoing prolonged non-cardiac surgery under general anaesthesia. Here, we report the findings of the internal vanguard feasibility phase of the trial undertaken in four large metropolitan hospitals in Australia and New Zealand that included the first 210 patients of a planned overall 2640 trial sample, with eight pre-specified endpoints evaluating protocol implementation and safety. We screened a total of 956 participants between 1 September 2019 and 26 January 2021, with data from 210 participants included in the analysis. Median (IQR [range]) time-weighted average intra-operative Fi O2 was 0.30 (0.26-0.35 [0.20-0.59]) and 0.47 (0.44-0.51 [0.37-0.68]) for restricted and standard care, respectively (mean difference (95%CI) 0.17 (0.14-0.20), p < 0.001). Median time-weighted average intra-operative Fi O2 was 0.83 (0.80-0.85 [0.70-0.91]) for liberal oxygen therapy (mean difference (95%CI) compared with standard care 0.36 (0.33-0.39), p < 0.001). All feasibility endpoints were met. There were no significant patient adverse events. These data support the feasibility of proceeding with the HOT-ROX trial without major protocol modifications.


Asunto(s)
Terapia por Inhalación de Oxígeno , Oxígeno , Adulto , Humanos , Estudios de Factibilidad , Terapia por Inhalación de Oxígeno/métodos , Australia , Nueva Zelanda
2.
Anaesthesia ; 77(2): 185-195, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34333761

RESUMEN

We implemented the World Health Organization surgical safety checklist at Auckland City Hospital from November 2007. We hypothesised that the checklist would reduce postoperative mortality and increase days alive and out of hospital, both measured to 90 postoperative days. We compared outcomes for cohorts who had surgery during 18-month periods before vs. after checklist implementation. We also analysed outcomes during 9 years that included these periods (July 2004-December 2013). We analysed 9475 patients in the 18-month period before the checklist and 10,589 afterwards. We analysed 57,577 patients who had surgery from 2004 to 2013. Mean number of days alive and out of hospital (95%CI) in the cohort after checklist implementation was 1.0 (0.4-1.6) days longer than in the cohort preceding implementation, p < 0.001. Ninety-day mortality was 395/9475 (4%) and 362/10,589 (3%) in the cohorts before and after checklist implementation, multivariable odds ratio (95%CI) 0.93 (0.80-1.09), p = 0.4. The cohort changes in these outcomes were indistinguishable from longer-term trends in mortality and days alive and out of hospital observed during 9 years, as determined by Bayesian changepoint analysis. Postoperative mortality to 90 days was 228/5686 (4.0%) for Maori and 2047/51,921 (3.9%) for non-Maori, multivariable odds ratio (95%CI) 0.85 (0.73-0.99), p = 0.04. Maori spent on average (95%CI) 1.1 (0.5-1.7) fewer days alive and out of hospital than non-Maori, p < 0.001. In conclusion, our patients experienced improving postoperative outcomes from 2004 to 2013, including the periods before and after implementation of the surgical checklist. Maori patients had worse outcomes than non-Maori.


Asunto(s)
Lista de Verificación/tendencias , Auditoría Médica/tendencias , Alta del Paciente/tendencias , Seguridad del Paciente , Complicaciones Posoperatorias/epidemiología , Organización Mundial de la Salud , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Lista de Verificación/métodos , Femenino , Humanos , Masculino , Auditoría Médica/métodos , Persona de Mediana Edad , Complicaciones Posoperatorias/diagnóstico , Estudios Retrospectivos , Adulto Joven
3.
Anaesthesia ; 77(12): 1346-1355, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36110039

RESUMEN

The Difficult Airway Society recommends that all patients should be pre-oxygenated before the induction of general anaesthesia, but this may not always be easy or comfortable and anaesthesia may often be induced without full pre-oxygenation. We tested the hypothesis that high-flow nasal oxygen cannulae would be easier and more comfortable than facemasks for pre-oxygenation. We randomly allocated 199 patients undergoing elective surgery aged ≥ 10 years to pre-oxygenation using either high-flow nasal oxygen or facemask. Ease and comfort were assessed by anaesthetists and patients on 10-cm visual analogue scale and six-point smiley face scale, respectively. Secondary endpoints included end-tidal oxygen fraction after securing a definitive airway and time to secure an airway. A mean difference (95%CI) between groups in ratings of -0.76 (-1.25 to -0.27) cm for ease of use (p = 0.003) and -0.45 (-0.75 to -0.13) points for comfort (p = 0.006), both favoured high-flow nasal oxygen. A mean difference (95%CI) between groups in end-tidal oxygen fraction of 3.89% (2.41-5.37%) after securing a definitive airway also favoured high-flow nasal oxygen (p < 0.001). There was no significant difference between groups in the number of patients with hypoxaemia (Sp O2 < 90%) or severe hypoxaemia (Sp O2 < 85%) lasting ≥ 1 min or ≥ 2 min; in the proportion of patients with an end-tidal oxygen fraction < 87% in the first 5 min after tracheal intubation (52.2% vs. 58.9% in facemask and high-flow nasal oxygen groups, respectively; p = 0.31); or in time taken to secure an airway (11.6 vs. 12.2 min in facemask and high-flow nasal oxygen groups, respectively; p = 0.65). In conclusion, we found pre-oxygenation with high-flow nasal oxygen to be easier for anaesthetists and more comfortable for patients than pre-oxygenation with a facemask, with no clinically relevant differences in end-tidal oxygen fraction after securing a definitive airway or time to secure an airway. The differences in ease and comfort were modest.


Asunto(s)
Máscaras , Oxígeno , Humanos , Cánula , Administración Intranasal , Hipoxia , Terapia por Inhalación de Oxígeno
4.
J Nematol ; 52: 1-3, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32141268

RESUMEN

In October 2019, samples of galled roots with rhizosphere soil were collected from declining Elaeocarpus decipiens in Hernando County, Florida. Extracted root-knot nematodes were identified by both molecular and morphological methods as Meloidogyne enterolobii. This is a first report of this regulated root-knot nematode on Elaeocarpus decipiens in Florida.In October 2019, samples of galled roots with rhizosphere soil were collected from declining Elaeocarpus decipiens in Hernando County, Florida. Extracted root-knot nematodes were identified by both molecular and morphological methods as Meloidogyne enterolobii. This is a first report of this regulated root-knot nematode on Elaeocarpus decipiens in Florida.

5.
J Nematol ; 52: 1-4, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32436669

RESUMEN

Samples of galled roots, resembling those induced by root-knot nematodes, and rhizosphere soil were collected from potted plants of Ulmus parvifolia cvs. Allee and Drake in Lake County, Florida. Nematode species were identified using both molecular analysis and morphology of perineal patterns. Meloidogyne enterolobii and M. javanica were identified from U. parvifolia cv. Allee. Meloidogyne arenaria and M. javanica were identified from U. parvifolia cv. Drake. This is a first report of these nematode species infecting Chinese Elm in Florida.Samples of galled roots, resembling those induced by root-knot nematodes, and rhizosphere soil were collected from potted plants of Ulmus parvifolia cvs. Allee and Drake in Lake County, Florida. Nematode species were identified using both molecular analysis and morphology of perineal patterns. Meloidogyne enterolobii and M. javanica were identified from U. parvifolia cv. Allee. Meloidogyne arenaria and M. javanica were identified from U. parvifolia cv. Drake. This is a first report of these nematode species infecting Chinese Elm in Florida.

6.
Br J Anaesth ; 122(2): 198-205, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30686305

RESUMEN

BACKGROUND: Etomidate is frequently selected over propofol for induction of anaesthesia because of a putatively favourable haemodynamic profile, but data confirming this perception are limited. METHODS: Patients undergoing cardiac surgery were randomised to induction of anaesthesia with propofol or etomidate. Phase I (n=75) was conducted as open-label, whereas Phase II (n=75) was double blind. Mean arterial blood pressure (MAP) and boluses of vasopressor administered after induction were recorded. The primary endpoint was the area under the curve below baseline MAP (MAP-time integral) during the 10 min after induction. Secondary endpoints were the use of vasopressors over the same period, and the effect of blinding on the aforementioned endpoints. Groups were compared using regression models with phase and anaesthetist as factors. RESULTS: The mean difference between etomidate and propofol in the MAP-time integral below baseline was 2244 mm Hg s (95% confidence interval, 581-3906; P=0.009), representing a 34% greater reduction with propofol. Overall, vasopressors were used in 10/75 patients in the etomidate group vs 21/75 in the propofol group (P=0.38), and in 20/74 patients during the blinded phase vs 11/76 during the open-label phase (P=0.31). The interaction between randomisation and phase (open-labelled or blinded) was not significant for either primary (P=0.73) or secondary endpoints (P=0.90). CONCLUSIONS: Propofol caused a 34% greater reduction in MAP-time integral from baseline after induction of anaesthesia than etomidate, despite more frequent use of vasopressors with propofol, confirming the superior haemodynamic profile of etomidate in this context. The proportion of patients receiving vasopressors increased slightly, albeit not significantly, in both groups in the blinded phase. CLINICAL TRIAL REGISTRATION: Australian and New Zealand Clinical Trials Registry, ACTRN12614000717651.


Asunto(s)
Anestesia General/métodos , Procedimientos Quirúrgicos Cardíacos/métodos , Etomidato , Hemodinámica/efectos de los fármacos , Hipnóticos y Sedantes , Propofol , Adulto , Anciano , Anciano de 80 o más Años , Presión Arterial , Puente de Arteria Coronaria , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Vasoconstrictores/uso terapéutico
7.
Epidemiol Infect ; 140(11): 1993-2002, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22214820

RESUMEN

Travel is a risk factor for Legionnaires' disease. In 2008, two cases were reported in condominium guests where we investigated a 2001 outbreak. We reinvestigated to identify additional cases and determine whether ongoing transmission resulted from persistent colonization of potable water. Exposures were assessed by matched case-control analyses (2001) and case-series interviews (2008). We sampled potable water and other water sources. Isolates were compared using sequence-based typing. From 2001 to 2008, 35 cases were identified. Confirmed cases reported after the cluster in 2001-2002 were initially considered sporadic, but retrospective case-finding identified five additional cases. Cases were more likely than controls to stay in tower 2 of the condominium [matched odds ratio (mOR) 6·1, 95% confidence interval (CI) 1·6-22·9]; transmission was associated with showering duration (mOR 23·0, 95% CI 1·4-384). We characterized a clinical isolate as sequence type 35 (ST35) and detected ST35 in samples of tower 2's potable water in 2001, 2002, and 2008. This prolonged outbreak illustrates the importance of striving for permanent Legionella eradication from potable water.


Asunto(s)
Trazado de Contacto , Brotes de Enfermedades , Agua Potable/microbiología , Legionella pneumophila/aislamiento & purificación , Enfermedad de los Legionarios/transmisión , Viaje , Microbiología del Agua , Anciano , Estudios de Casos y Controles , Vivienda , Humanos , Legionella pneumophila/clasificación , Enfermedad de los Legionarios/diagnóstico , Enfermedad de los Legionarios/epidemiología , Enfermedad de los Legionarios/prevención & control , Modelos Logísticos , Persona de Mediana Edad , Análisis Multivariante , Nevada/epidemiología , Oportunidad Relativa , Estudios Retrospectivos , Factores de Riesgo , Serotipificación
8.
Arch Environ Contam Toxicol ; 56(4): 631-7, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19057835

RESUMEN

There is very little information on the overall level of estrogenic activity, or concentrations of specific hormonal compounds in wastewater treatment plant (WWTP) discharges in Australia, compared with Europe, Japan, and North America. To partly address this, in 2004, water samples were collected as "grab" or "spot" samples from 12 WWTP facilities across southern Victoria at the point at which effluent enters the environment, either as recycled water or direct discharge to the receiving water. The WWTPs were of a variety of treatment types and served a diverse range of rural and regional municipalities. For instance, of the 12 WWTPs, 3 served municipalities with populations greater than 100,000, 4 with populations between 20,000 and 100,000, and 5 with populations less than 5,000. The principal treatment process in six was an activated sludge system, and three were trickle-filter-based systems. The remaining plants fall into a "miscellaneous" category, each plant having a mixture of treatment processes within the overall systems. The estrogenic activity and 17beta-estradiol concentrations of the samples were assessed using a yeast-based, in vitro reporter gene assay and enzyme-linked immunosorbant assays, respectively. Most of the effluents showed estrogenic activity in the assays (hER, no response: 7.9 ng/L EEQ; mER, no response: 44.5 ng/L EEQ). There was no correlation between estrogenic response and the results of a concurrent toxicity assay, suggesting that a lack of bioassay response was related to lack of estrogenic compounds, rather than the direct toxic effect of the sample. Estradiol concentrations were for the most part in the range 2-5 ng/L, with one sample at 18 ng/L. Despite the assurance our results might provide (of minimal impact in most cases if there is significant dilution), there is still a need for further extensive on-ground reassurance research to provide data for higher-level risk assessment by industry and government agencies. In particular, more research is warranted to verify the estrogenic activity and to expand the range of specific hormone/metabolites reported in these studies. Moreover, studies are required to determine if the estrogenic activity reported in this and other recent Australian studies is sufficient to induce a physiological effect in exposed aquatic organisms, especially Australian native fish.


Asunto(s)
Estradiol/análisis , Estradiol/toxicidad , Estrógenos/análisis , Estrógenos/toxicidad , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad , Monitoreo del Ambiente/métodos , Photobacterium/efectos de los fármacos , Photobacterium/fisiología , Aguas del Alcantarillado/análisis , Australia del Sur , Técnicas del Sistema de Dos Híbridos
9.
J Clin Invest ; 56(5): 1239-49, 1975 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1184748

RESUMEN

The mutation in a young gouty male with a partial deficiency of hypoxanthine-guanine phosphoribosyltransferase has been evaluated. The serum uric acid was 11.8 mg/100 ml, and the urinary uric acid excretion was 1,279 mg/24 h. Erythrocyte hypoxanthine-guanine phosphoribosyltransferase was 34.2 nmol/h/mg, adenine phosphoribosyltransferase was 36.5 nmol/h/mg and phosphoribosylpyrophosphate was 2.6 muM. Hypoxanthine-guanine phosphoribosyltransferase from peripheral leukocytes and cultured diploid skin fibroblasts was within the normal range, but enzyme activity in rectal mucosa was below the normal range. Initial velocity studies of the normal enzyme and the mutant enzyme from erythrocytes with the substrates hypoxanthine, guanine, or phosphoribosylpyrophosphate showed that the Michaelis constants were similar. Product inhibition studies distinguished the mutant enzyme from the normal enzyme. Hyperbolic kinetics with increasing phosphoribosylpyrophosphate were converted to sigmoid kinetics by 0.2 mM GMP with the mutant enzyme but not with the normal enzyme. The mutant erythrocyte hypoxanthine-guanine phosphoribosyltransferase was inactivated normally at 80 degrees C and had a normal half-life in the peripheral circulation. The mol wt of 48,000 was similar to the normal enzyme mol wt of 47,000. With isoelectric focusing, the mutant erythrocyte enzyme had two major peaks with isoelectric pH's of 5.50 and 5.70, in contrast to the isoelectric pH's of 5.76, 5.82, and 6.02 of the normal isozymes. Isoelectric focusing of leukocyte extracts from the patient revealed the presence of the mutant enzyme. Cultured diploid fibroblasts from the propositus appeared to function normally, as shown by the inability to grow in 50-100 muM azaguanine and by the normal incorporation of [14C]hypoxanthine into nucleic acid. In contrast, erythrocytes from the patient displayed abnormal properties, including the increased synthesis of phosphoribosylphyrophosphate and elevated functional activity of orotate phosphoribosyltransferase and orotidylic decarboxylase. These unique kinetic, physical, and functional properties provide support for heterogeneous structural gene mutations in partial deficiencies of hypoxanthine-guanine phosphoribosyltransferase.


Asunto(s)
Genes , Gota/enzimología , Hipoxantina Fosforribosiltransferasa/deficiencia , Mutación , Adulto , Eritrocitos/enzimología , Femenino , Fibroblastos/enzimología , Gota/sangre , Gota/genética , Humanos , Técnicas In Vitro , Linaje , Ácido Úrico/sangre
10.
J Natl Cancer Inst ; 68(2): 271-8, 1982 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-6278190

RESUMEN

The hepatocarcinogenicity of aflatoxin B1 (AFB1) was compared in male Syrian golden hamsters and inbred F344 rats. AFB1 was administered by gavage 5 days/week for 6 weeks at doses of 1 and 2 mg/kg body weight/day to rats and hamsters, respectively; rate did not survive beyond 3 weeks with doses of 2 mg/kg/day. After 6 weeks the animals either received no further treatment or were given 0.1% phenobarbital sodium in the drinking water. ATPase-deficient foci of hepatic parenchymal cells, neoplastic nodules, and hepatocellular carcinomas were observed in liver sections from AFB1-treated rats killed at 6, 14, or 23 weeks; they were not seen in sections from AFB1-treated hamsters killed at 6, 14, or 46 weeks. Each of the 50 AFB1-treated rats developed hepatocellular carcinomas by 46 weeks; many also had cholangiocarcinomas and mixed hepatocellular-cholangiocellular carcinomas. Hepatocellular carcinomas were found in only 2 of 49 AFB1-treated hamsters by 78 weeks. At this time cholangiocarcinomas were found in 15 hamsters, and microscopic cholangiomas were seen in all of the livers. Compared to the rat, the hamster was resistant to the hepatotoxic and hepatocellular carcinogenic effects of AFB1.


Asunto(s)
Adenoma de los Conductos Biliares/inducido químicamente , Aflatoxinas/administración & dosificación , Neoplasias Hepáticas Experimentales/inducido químicamente , Adenoma de los Conductos Biliares/patología , Aflatoxina B1 , Animales , Cricetinae , Relación Dosis-Respuesta a Droga , Neoplasias Hepáticas Experimentales/patología , Masculino , Mesocricetus , Ratas , Ratas Endogámicas F344 , Factores de Tiempo
11.
Cancer Res ; 41(5): 1585-93, 1981 May.
Artículo en Inglés | MEDLINE | ID: mdl-7214332

RESUMEN

The development of glucose-6-phosphatase (G-6-Pase-)-deficient hyperbasophilic foci was analyzed at 4-week intervals in the livers of CD-1 and C57BL/6J x C3H/HeJ F1 (hereafter called B6C3F1) mice given a single i.p. injection of diethylnitrosamine (DEN) (0.1, 0.2, or 0.4 mumol/g body weight) within 24 hr after birth. Transections of G-6-Pase-deficient foci of hepatocytes were readily discernible in liver sections of DEN-treated mice of either sex at 8 weeks of age. The size and number of these foci per liver increased with time. The occurrence of G-6-Pase-deficient focus transections with diameters as large as 1 mm coincided with the gross appearance of 1-mm gray-white nodules in the livers of male B6C3F1 mice at 16 weeks of age and in females at 32 weeks of age. Transections of all grossly visible hepatic nodules from male and female mice were G-6-Pase deficient and hyperbasophilic; the great majority were diagnosed as mouse hepatomas type A. After a single neonatal dose of DEN, the number and rate of growth of the G-6-Pase-deficient foci and the incidence and rate of appearance of gross hepatomas were greater in the liver of male than in those of female mice. In contrast, the average numbers of G-6-Pase-deficient foci in the livers of male and androgenized female B6C3F1 mice at 36 weeks of age were approximately equal and about twice that observed for the livers of DEN-treated female controls. Quantitation of carcinogen-induced histochemically detectable foci and hepatomas as a function of time provides a useful tool for the analysis of initiation and promotion in the mouse liver.


Asunto(s)
Animales Recién Nacidos/fisiología , Dietilnitrosamina , Deficiencia de Glucosafosfato Deshidrogenasa/inducido químicamente , Neoplasias Hepáticas Experimentales/inducido químicamente , Hígado/enzimología , Nitrosaminas , Factores de Edad , Animales , Castración , Femenino , Neoplasias Hepáticas Experimentales/enzimología , Masculino , Ratones , Factores Sexuales , Testosterona/farmacología
12.
Biochim Biophys Acta ; 1201(1): 85-93, 1994 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-7918587

RESUMEN

The development of haem biosynthetic enzyme activity during normoblastic human erythropoiesis was examined in seven patients. The first and last enzymes of the haem biosynthetic pathway, ALA synthase and ferrochelatase, were assayed by radiochemical/high performance liquid chromatographic (HPLC) methods. An assay for ferrochelatase activity in human bone marrow was developed. Enzyme substrates were protoporphyrin IX and 59Fe2+ ions. 59Fe-labelled haem was isolated by organic solvent extraction/sorbent extraction followed by reversed-phase HPLC. Optimal activity occurred at pH 7.3 in the presence of ascorbic acid, in darkness and under anaerobic conditions. Haem production was proportional to cell number and was linear with time to 30 min. The assay was sensitive to the picomolar range of haem production. ALA synthase and ferrochelatase activity was assayed in four highly purified age-matched erythroid cell populations. ALA synthase activity was maximal in the most immature erythroid cells and diminished as the cells matured with an overall five fold loss of activity from proerythroblast to late erythroblast development. Ferrochelatase activity was, however, more stable with less than a two fold change in activity observed during the same period of erythroid differentiation. Maximal activity occurred in erythroid fractions enriched with intermediate erythroblasts. These results support sequential rather than simultaneous appearance of these enzymes during normoblastic erythropoiesis. Quantitative analysis of relative enzyme activity however indicates that at all times during erythroid differentiation ferrochelatase activity is present in excess to that theoretically required relative to ALA synthase activity since ALA and haem are not produced in stoichiometric amounts. The lability of ALA synthase versus the stability and gross relative excess of ferrochelatase activity indicates a far greater role for ALA synthase in the regulation of erythroid haem biosynthesis than for ferrochelatase.


Asunto(s)
5-Aminolevulinato Sintetasa/metabolismo , Eritroblastos/enzimología , Ferroquelatasa/metabolismo , Hemo/biosíntesis , Médula Ósea/enzimología , Diferenciación Celular , Eritropoyesis , Hemo/aislamiento & purificación , Humanos , Radioisótopos de Hierro
13.
Biochim Biophys Acta ; 1096(2): 170-4, 1991 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-2001431

RESUMEN

Our laboratory has previously reported that progestins stimulate growth of the human breast cancer cell line T47D. In an attempt to probe further into this stimulation, we are investigating progestin effects on thymidine kinase (EC 2.7.1.21), an enzyme known to be involved in growth regulation. This report relates our finding that progestins stimulate thymidine kinase activity, at physiological progestin concentrations, in a dose-responsive manner. Estradiol-17 beta also stimulates, but testosterone, hydrocortisone and aldosterone do not. The antiprogestin RU486 inhibits progestin stimulation, but also stimulates on its own. Maximal by 24 h, the progestin stimulation then falls off with time. Experiments with actinomycin D and cycloheximide suggest that the thymidine kinase stimulation depends on new RNA and protein synthesis. These data shed further light on progestin stimulation of the growth of human breast cancer. To our knowledge, this is the first report of progestin stimulation of thymidine kinase in human breast cancer cells.


Asunto(s)
Neoplasias de la Mama/enzimología , Progestinas/farmacología , Timidina Quinasa/metabolismo , Neoplasias de la Mama/patología , División Celular/efectos de los fármacos , Dactinomicina/farmacología , Relación Dosis-Respuesta a Droga , Humanos , Técnicas In Vitro , Mifepristona/farmacología , Promegestona/farmacología , Factores de Tiempo , Células Tumorales Cultivadas
14.
Biochim Biophys Acta ; 930(2): 167-72, 1987 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-2441761

RESUMEN

We have previously reported that physiological levels of progestins alone stimulate lactate dehydrogenase in a dose-responsive manner in the progesterone-receptor-rich human breast cancer cell line T-47D. Using isozyme electrophoresis, we have not found that lactate dehydrogenase isozyme 5 is the only isozyme detectable in these cells, as has been reported for other human breast cancer cells in long-term tissue culture. Upon treatment with progestins, isozyme 5 remains the only isozyme detectable. T-47D cells were plated in charcoal-stripped serum-containing medium and grown for 2 days before treatment with progestin. Lactate dehydrogenase stimulation then plateaued after around 2-3 days of treatment with progestin and was maintained until around day 5, following which a decline in enzyme activity occurred. The effect is specific for progestins, and inhibited by the anti-progestin RU-38486 (17 beta-hydroxy-11 beta-(4-dimethyl-aminophenyl-1)-17 alpha-(prop-1-ynil)-estra-4,9-dien-3-one). Experiments using actinomycin D and cycloheximide suggests that the effect is dependent on RNA and protein synthesis, respectively. Lactate dehydrogenase stimulation occurs regardless of the presence of the estrogenic pH indicator Phenol red, and of whether it was analyzed per mg DNA or per mg protein.


Asunto(s)
Neoplasias de la Mama/enzimología , L-Lactato Deshidrogenasa/análisis , Progestinas/farmacología , Línea Celular , Estrenos/farmacología , Femenino , Humanos , Mifepristona , Proteínas de Neoplasias/biosíntesis , Promegestona/farmacología , ARN/biosíntesis
15.
Biochim Biophys Acta ; 513(2): 285-91, 1978 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-102347

RESUMEN

Human placental hexosaminidase B and beta-galactosidase are taken up very poorly by human fibroblasts in culture. However, if fibroblasts manifesting genetically determined deficiencies of these lysosomal hydrolases are first treated with concanavalin A, then enzyme uptake is markedly increased. Enzyme activity which becomes associated with concanavalin A-treated fibroblasts maintained at 4 degrees C can be greatly removed by treatment with haptene sugar, while enzyme activity which becomes associated with cells maintained at 37 degrees C is refractory to haptens treatment. These results are interpreted as an initial binding of enzyme to concanvalin A molecules located at the cell surface, followed by an active cellular process leading to internalization of the lectin-enzyme complexes.


Asunto(s)
Concanavalina A/farmacología , Galactosidasas/metabolismo , Hexosaminidasas/metabolismo , Lisosomas/enzimología , beta-Galactosidasa/metabolismo , Transporte Biológico Activo/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Fibroblastos , Glicoproteínas/metabolismo , Humanos , Estimulación Química
16.
Biochim Biophys Acta ; 1034(1): 1-3, 1990 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-2328254

RESUMEN

Porphyrin content and 5-aminolaevulinate synthase activity of the Harderian gland were measured in intact and gonadectomized male and female hamsters; porphyrin profiles were analysed by high-pressure liquid chromatography. The total porphyrin content of the two female groups was similar, but enzyme activity in females ovariectomised for 20 weeks significantly decreased. Intact males have low porphyrin content and enzyme activity, while in castrates (6 weeks) both increased to female levels. Protoporphyrin IX formed 93% of total porphyrins in intact females, compared with 70% of total porphyrins in intact males. The remainder in both sexes was chiefly penta- and hexacarboxylic porphyrins and coproporphyrin and (in females) Harderoporphyrin. Gonadectomy in either sex resulted in protoporphyrin levels intermediate between male and female values.


Asunto(s)
Glándula de Harder/análisis , Aparato Lagrimal/análisis , Porfirinas/análisis , 5-Aminolevulinato Sintetasa/análisis , Animales , Castración , Cromatografía Líquida de Alta Presión , Cricetinae , Femenino , Masculino , Mesocricetus , Protoporfirinas/análisis , Factores Sexuales
17.
J Clin Oncol ; 2(6): 643-51, 1984 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6374057

RESUMEN

Patients with visceral patterns of metastatic breast cancer were stratified according to dominant metastatic site and performance status and then randomized to therapy with cyclophosphamide, doxorubicin, and 5-fluorouracil (CAF) or CAF alternating with a "cell-cycle active" regimen including cytosine arabinoside, methotrexate with leucovorin rescue, and oncovin ( CAMELEON ). One hundred eighty-seven patients were randomized; response rate for CAF was 44% and for CAF + CAMELEON , 40%. Durations of disease control and survival were not significantly different. Toxicity of CAF was as anticipated with predominant granulocytopenia, vomiting, and alopecia. Toxicity of CAMELEON was less severe than that of CAF, and CAF toxicity was not worsened by preceding courses of CAMELEON ; however, the CAF- CAMELEON regimen was cumbersome and complex leading to both physician and patient noncompliance. Contrary to the preliminary results of a pilot study, and preliminary reports of the present trial suggesting benefit for the CAF- CAMELEON regimen the present randomized trial does not confirm any significant benefit of CAF- CAMELEON over CAF alone in patients with visceral metastatic breast cancer although this conclusion must be viewed in light of the high inevaluability rate due to patient and physician noncompliance.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Agranulocitosis/inducido químicamente , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias de la Mama/mortalidad , Ensayos Clínicos como Asunto , Ciclofosfamida/administración & dosificación , Ciclofosfamida/efectos adversos , Citarabina/administración & dosificación , Citarabina/efectos adversos , Doxorrubicina/administración & dosificación , Doxorrubicina/efectos adversos , Esquema de Medicación , Resistencia a Medicamentos , Femenino , Fluorouracilo/administración & dosificación , Fluorouracilo/efectos adversos , Humanos , Leucovorina/administración & dosificación , Leucovorina/efectos adversos , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/secundario , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/secundario , Metotrexato/administración & dosificación , Metotrexato/efectos adversos , Náusea/inducido químicamente , Distribución Aleatoria , Trombocitopenia/inducido químicamente , Vincristina/administración & dosificación , Vincristina/efectos adversos , Vómitos/inducido químicamente
18.
J Clin Oncol ; 14(4): 1156-64, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8648370

RESUMEN

PURPOSE: To assess the clinical toxicity and outcome associated with a comprehensive supportive care approach in poor-risk breast cancer (BrCA) patients with high-dose chemotherapy (HDC). PATIENTS AND METHODS: One hundred twenty-five consecutive patients with stages II, III or metastatic breast cancer received HDC between February 1992 and June 1994. Recipients received 4 days of continuous infusion of cyclophosphamide 1.5 g/m2/d, thiotepa 125 mg/m2/d, and carboplatin 200 mg/m2/d followed by infusion of bone marrow or peripheral-blood stem cells (PBSC) and recombinant human growth factor (rhu-GF) support. Patients received similar supportive care that included administration of prophylactic antibiotics, management of neutropenic fevers, and transfusion support. RESULTS: There were 38 women with stage II or III (27 patients with > or = 10 lymph nodes), four with stage IIIB, and 83 with metastatic breast cancer. The median age was 44 years (range, 27 to 61). Grade II or greater nonhematologic toxicities included diarrhea (66%), stomatitis (33%), hepatic venoocclusive disease (VOD) (5%), and pulmonary toxicity (4%). Myeloid and platelet engraftment was comparable between bone marrow and PBSC recipients (P > .1). Infectious complications were rare and consisted of gram-negative bacteremia (1.6%), gram-positive bacteremia (1.6%), fungemia (1.6%), and documented or suspected aspergillosis infection (3%). There was one treatment-related death secondary to severe VOD. CONCLUSION: A comprehensive supportive care approach was associated with a low treatment-related mortality rate of less than 1%. With the observed reduction in treatment-related mortality, it is reasonable to evaluate the efficacy of HDC in women with less than 10 positive nodes and stage II disease in well-designed clinical trials.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Trasplante de Médula Ósea , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/terapia , Trasplante de Células Madre Hematopoyéticas , Análisis Actuarial , Adulto , Algoritmos , Antineoplásicos Alquilantes/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias de la Mama/patología , Carboplatino/administración & dosificación , Terapia Combinada , Ciclofosfamida/administración & dosificación , Femenino , Humanos , Metástasis Linfática , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Factores de Riesgo , Análisis de Supervivencia , Tiotepa/administración & dosificación , Trasplante Autólogo , Resultado del Tratamiento
19.
Diabetes ; 38(12): 1544-8, 1989 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2555241

RESUMEN

Vitamin A (retinol) is required for insulin secretion, and retinoic acid substitutes for retinol in this function. To determine if retinol acts at the beta-cell level, we assayed beta-cells of the rat insulinoma (RINm5F) line for cytosolic retinol- and retinoic acid-binding proteins (CRBP and CRABP) by radioimmunoassay (RIA) and [3H]retinol and [3H]retinoic acid binding to cytosol extracts. Furthermore, we tested whether insulin release from cells was affected by addition of retinol or retinoic acid to culture medium. RINm5F cells were grown to near confluence before assay of CRBP and CRABP. Scatchard analysis showed the Kd for retinol to be approximately 6 nM at a level of 4.5 pmol/mg protein or 300,000 sites/cell. Sucrose density-gradient assay showed single discrete peaks migrating at 2S for both retinol and retinoic acid. RIA of whole-cell extracts showed CRBP and CRABP levels of 5.27 +/- 0.41 and 2.95 +/- 0.75 pmol/mg protein, respectively. Retinol (1.75 microM) and retinoic acid (0.175 and 1.75 microM) increased KCl-induced insulin release. Considered together, the presence of CRBP and CRABP in a beta-cell line and the increase in KCl-induced insulin release by retinol and retinoic acid are consistent with the idea that retinol has a functional role in insulin secretion and suggest a potential mechanism of action at the beta-cell level similar to that observed in other retinoid-responsive cells.


Asunto(s)
Proteínas Portadoras/metabolismo , Insulina/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas de Unión al Retinol/metabolismo , Tretinoina/farmacología , Células Tumorales Cultivadas/metabolismo , Vitamina A/farmacología , Animales , Línea Celular , Secreción de Insulina , Insulinoma , Cinética , Neoplasias Pancreáticas , Cloruro de Potasio/farmacología , Ratas , Receptores de Ácido Retinoico , Proteínas Celulares de Unión al Retinol , Células Tumorales Cultivadas/efectos de los fármacos
20.
Blood Rev ; 4(2): 88-96, 1990 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2194599

RESUMEN

The porphyrias are a group of metabolic disorders arising from defects in the haem biosynthetic pathway. Most forms are inherited as Mendelian autosomal dominant characters, but some are recessive and others acquired. There is a linked group of diseases, which are not porphyrias, but have in common alterations of haem biosynthesis. The haem biosynthetic pathway is now well understood and the molecular biology of its function and dysfunction in the porphyrias is currently an area of major investigation. The acute porphyrias are of most importance since attacks of these may be life-threatening. A variety of factors may precipitate these attacks including various drugs, alcohol, strict dieting or fasting and hormonal fluctuations. The non-acute porphyrias are largely dermatological conditions, which present clinically as cutaneous photosensitivity. The dermatological changes are brought about by the photosensitizing properties of circulating porphyrins. On the basis of this photoactivity, porphyrins are now being used, therapeutically, in the treatment of cancer.


Asunto(s)
Porfirias , Enfermedad Aguda , Hemo/biosíntesis , Humanos , Fotoquimioterapia , Porfirias/clasificación , Porfirias/etiología , Porfirias/terapia , Enfermedades de la Piel/etiología , Enfermedades de la Piel/terapia
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