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1.
EBioMedicine ; 39: 510-519, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30552064

RESUMO

BACKGROUND: In winter in Mongolia, 80% of adults have 25-hydroxyvitamin D (25(OH)D) concentrations <25 nmol/l (<10 ng/ml) and 99% have <50 nmol/l (<20 ng/ml). The vitamin D dose to avert deficiency during pregnancy in this population is unknown. METHODS: We conducted a randomized, controlled, double-blind trial of daily 600, 2000, or 4000 IU vitamin D3 for pregnant women in Mongolia (Clinicaltrials.gov #NCT02395081). We examined 25(OH)D concentrations at baseline (12-16 weeks' gestation), 36-40 weeks' gestation and in umbilical cord blood, using enzyme linked fluorescent assay. Sample size was determined to detect 0.4 standard deviation differences in 25(OH)D concentrations with 80% power. FINDINGS: 119 pregnant women were assigned 600 IU, 121 assigned 2000 IU and 120 assigned 4000 IU from February 2015 through December 2016. Eighty-eight percent of participants took ≥80% of assigned supplements. At baseline, 25(OH)D concentrations were similar across arms; overall mean ±â€¯standard deviation concentration was 19 ±â€¯22 nmol/l; 91% were < 50 nmol/l. At 36-40 weeks, 25(OH)D concentrations increased to 46 ±â€¯21, 70 ±â€¯23, and 81 ±â€¯29 nmol/l for women assigned 600, 2000, and 4000 IU, respectively (p < 0.0001 across arms; p = 0.002 for 2000 vs. 4000 IU). Mean umbilical cord 25(OH)D concentrations differed by study arm (p < 0.0001 across arms; p < 0.0001 for 2000 vs. 4000 IU) and were proportional to maternal concentrations. There were no adverse events, including hypercalcemia, attributable to vitamin D supplementation. INTERPRETATION: Daily supplementation of 4000 IU during pregnancy is safe and achieved higher maternal and neonatal 25(OH)D concentrations than 2000 IU. Daily 600 IU supplements are insufficient to prevent vitamin D deficiency in Mongolia. FUND: Anonymous foundation and Brigham and Women's Hospital.


Assuntos
Sangue Fetal/química , Trimestres da Gravidez/sangue , Deficiência de Vitamina D/tratamento farmacológico , Vitamina D/análogos & derivados , Adulto , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Gravidez , Primeiro Trimestre da Gravidez/sangue , Terceiro Trimestre da Gravidez/sangue , Resultado do Tratamento , Vitamina D/administração & dosagem , Vitamina D/uso terapêutico , Adulto Jovem
2.
Astrobiology ; 17(11): 1123-1137, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29039682

RESUMO

In 2020, the ESA ExoMars and NASA Mars 2020 missions will be launched to Mars to search for evidence of past and present life. In preparation for these missions, terrestrial analog samples of rock formations on Mars are studied in detail in order to optimize the scientific information that the analytical instrumentation will return. Desert varnishes are thin mineral coatings found on rocks in arid and semi-arid environments on Earth that are recognized as analog samples. During the formation of desert varnishes (which takes many hundreds of years), organic matter is incorporated, and microorganisms may also play an active role in the formation process. During this study, four complementary analytical techniques proposed for Mars missions (X-ray diffraction [XRD], Raman spectroscopy, elemental analysis, and pyrolysis-gas chromatography-mass spectrometry [Py-GC-MS]) were used to interrogate samples of desert varnish and describe their capacity to sustain life under extreme scenarios. For the first time, both the geochemistry and the organic compounds associated with desert varnish are described with the use of identical sets of samples. XRD and Raman spectroscopy measurements were used to nondestructively interrogate the mineralogy of the samples. In addition, the use of Raman spectroscopy instruments enabled the detection of ß-carotene, a highly Raman-active biomarker. The content and the nature of the organic material in the samples were further investigated with elemental analysis and methylated Py-GC-MS, and a bacterial origin was determined to be likely. In the context of planetary exploration, we describe the habitable nature of desert varnish based on the biogeochemical composition of the samples. Possible interference of the geological substrate on the detectability of pyrolysis products is also suggested. Key Words: Desert varnish-Habitability-Raman spectroscopy-Py-GC-MS-XRD-ExoMars-Planetary science. Astrobiology 17, 1123-1137.


Assuntos
Clima Desértico , Exobiologia/métodos , Marte , Minerais/análise , Pintura/análise , Planeta Terra , Exobiologia/instrumentação , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Cromatografia Gasosa-Espectrometria de Massas/métodos , Minerais/química , Voo Espacial , Análise Espectral Raman/instrumentação , Análise Espectral Raman/métodos , Difração de Raios X/instrumentação , Difração de Raios X/métodos
3.
Food Chem ; 237: 1021-1024, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28763945

RESUMO

The oxidation potential of iron fortified goat and cow milks and casein phosphopeptides obtained from each species of milk was determined using malondialdehyde as an oxidation product marker. There was a reduction in oxidation when iron was 'bound' to milk or peptides compared to free ferrous sulphate in solution. However, goat milk produced significantly lower amounts of malondialdehyde of 0.46±0.04µgMDA/ml after 3days at 30°C compared to the blank of 1.25±0.16µgMDA/ml. The goat peptides produced non-significantly different levels of malondialdehyde compared to the blank containing no ferrous sulphate.


Assuntos
Alimentos Fortificados/análise , Leite/química , Animais , Caseínas , Feminino , Cabras , Ferro , Oxirredução , Peptídeos
4.
Andrology ; 5(3): 431-438, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28296285

RESUMO

Myeloperoxidase is a major neutrophil protein which generates oxidants that are highly reactive, and if present in seminal fluid, could be potentially damaging to spermatozoa. We recruited young males aged 18-35 years, unscreened for fertility status, for a pilot study measuring seminal plasma myeloperoxidase. On three occasions, over a 3-month period, we measured parameters of semen quality and correlated these with seminal myeloperoxidase protein and activity. After baseline measurement, participants were supplemented daily with 250 mg of vitamin C, a potent scavenger of reactive oxygen species with antiinflammatory activities. Seminal plasma from eight of the 12 participants had measurable concentrations of myeloperoxidase protein, across a broad range (15-250 ng/mL). Median myeloperoxidase protein concentrations were ~45-fold higher in semen samples with low vs. high sperm concentrations. Seminal plasma myeloperoxidase protein concentration was inversely correlated with the percentage of rapidly motile spermatozoa assessed by computer-assisted sperm analysis, and the total number of spermatozoa per ejaculate, but positively correlated with sperm maturity, measured by DNA staining ability. We measured an inverse correlation between semen vitamin C concentration and seminal plasma myeloperoxidase protein concentration, although vitamin C supplementation had no effect on semen quality. Our pilot data suggest that high concentrations of myeloperoxidase were present in the seminal plasma of many of our young participants, and that this may be associated with decreases in semen quality. A larger study is required to confirm these findings.


Assuntos
Antioxidantes/uso terapêutico , Ácido Ascórbico/uso terapêutico , Peroxidase/metabolismo , Sêmen/enzimologia , Espermatozoides/efeitos dos fármacos , Adolescente , Adulto , Ensaio de Imunoadsorção Enzimática , Humanos , Masculino , Projetos Piloto , Análise do Sêmen , Motilidade dos Espermatozoides/efeitos dos fármacos , Adulto Jovem
5.
Breast Cancer Res Treat ; 149(2): 373-83, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25528022

RESUMO

The PI3K pathway is a key mechanism of trastuzumab resistance, but early attempts to indirectly target this pathway with mTOR inhibitors have had limited success. We present the results of a preclinical study of the selective alpha/delta isoform dominant PI3K inhibitor BAY 80-6946 tested alone and in combination with HER2-targeted therapies in HER2-positive cell lines, including models with acquired resistance to trastuzumab and/or lapatinib. A panel of HER2-positive breast cancer cells were profiled for their mutational status using Sequenom MassARRAY, PTEN status by Western blot, and anti-proliferative response to BAY 80-6946 alone and in combination with the HER2-targeted therapies trastuzumab, lapatinib and afatinib. Reverse phase protein array was used to determine the effect of BAY 80-6946 on expression and phosphorylation of 68 proteins including members of the PI3K and MAPK pathways. The Boyden chamber method was used to determine if BAY 80-6946 affected cellular invasion and migration. BAY 80-6946 has anti-proliferative and anti-invasive effects when used alone in our panel of cell lines (IC50s 3.9-29.4 nM). BAY 80-6946 inhibited PI3K signalling and was effective in cells regardless of their PI3K, P53 or PTEN status. The combination of HER2-targeted therapies and BAY 80-6946 inhibited growth more effectively than either therapy used alone (with clear synergism in many cases), and can restore sensitivity to trastuzumab and lapatinib in cells with acquired resistance to either trastuzumab and/or lapatinib. The addition of BAY 80-6946 to HER2-targeted therapy could represent an improved treatment strategy for patients with refractory metastatic HER2-positive breast cancer, and should be considered for clinical trial evaluation.


Assuntos
Anticorpos Monoclonais Humanizados/farmacologia , Neoplasias da Mama/genética , Resistencia a Medicamentos Antineoplásicos , Inibidores de Fosfoinositídeo-3 Quinase , Pirimidinas/farmacologia , Quinazolinas/farmacologia , Receptor ErbB-2/genética , Anticorpos Monoclonais Humanizados/administração & dosagem , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Avaliação Pré-Clínica de Medicamentos , Sinergismo Farmacológico , Feminino , Humanos , Concentração Inibidora 50 , Lapatinib , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Mutação , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/administração & dosagem , Quinazolinas/administração & dosagem , Receptor ErbB-2/antagonistas & inibidores , Receptor ErbB-2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Trastuzumab
6.
Osteoporos Int ; 24(4): 1471-81, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22907737

RESUMO

UNLABELLED: Bisphosphonates reduce skeletal loss and fracture risk, but their use has been limited in patients with chronic kidney disease. This study shows skeletal benefits of zoledronic acid in an animal model of chronic kidney disease. INTRODUCTION: Bisphosphonates are routinely used to reduce fractures but limited data exists concerning their efficacy in non-dialysis chronic kidney disease. The goal of this study was to test the hypothesis that zoledronic acid produces similar skeletal effects in normal animals and those with kidney disease. METHODS: At 25 weeks of age, normal rats were treated with a single dose of saline vehicle or 100 µg/kg of zoledronic acid while animals with kidney disease (approximately 30% of normal kidney function) were treated with vehicle, low dose (20 µg/kg), or high dose (100 µg/kg) zoledronic acid, or calcium gluconate (3% in the drinking water). Skeletal properties were assessed 5 weeks later using micro-computed tomography, dynamic histomorphometry, and mechanical testing. RESULTS: Animals with kidney disease had significantly higher trabecular bone remodeling compared to normal animals. Zoledronic acid significantly suppressed remodeling in both normal and diseased animals yet the remodeling response to zoledronic acid was no different in normal and animals with kidney disease. Animals with kidney disease had significantly lower cortical bone biomechanical properties; these were partially normalized by treatment. CONCLUSIONS: Based on these results, we conclude that zoledronic acid produces similar amounts of remodeling suppression in animals with high turnover kidney disease as it does in normal animals, and has positive effects on select biomechanical properties that are similar in normal animals and those with chronic kidney disease.


Assuntos
Conservadores da Densidade Óssea/farmacologia , Remodelação Óssea/efeitos dos fármacos , Difosfonatos/farmacologia , Imidazóis/farmacologia , Insuficiência Renal Crônica/fisiopatologia , Animais , Fenômenos Biomecânicos , Densidade Óssea/efeitos dos fármacos , Conservadores da Densidade Óssea/administração & dosagem , Remodelação Óssea/fisiologia , Diáfises/efeitos dos fármacos , Diáfises/fisiopatologia , Difosfonatos/administração & dosagem , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Fêmur/efeitos dos fármacos , Fêmur/fisiopatologia , Imidazóis/administração & dosagem , Masculino , Osteogênese/efeitos dos fármacos , Osteogênese/fisiologia , Ratos , Ratos Sprague-Dawley , Tíbia/efeitos dos fármacos , Tíbia/patologia , Tíbia/fisiopatologia , Ácido Zoledrônico
7.
Int J Surg ; 9(4): 314-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21324384

RESUMO

OBJECTIVE: This study sought to determine the efficacy of post-operative wound infiltration with local anaesthetic following paediatric appendicectomy. METHOD: In a randomised, controlled, prospective, clinical trial children aged between five and sixteen years were assigned to one of three treatment arms; infiltration of the surgical wound with bupivicaine, saline, or no infiltration. Anaesthetic and analgesic protocols were employed. Patients and observers were blinded to the treatment group. The primary end-points were post-operative pain, scored at intervals during the first twenty post-operative hours, and additional post-operative analgesic requirements beyond that which was provided by a standard protocol. In addition, adverse wound outcomes were recorded. RESULTS: Eighty-eight children were recruited. There were no differences in age, sex or other confounding variables between groups. There was no significant difference in mean pain scores or analgesic requirements between groups through-out the post-operative period. CONCLUSION: Wound infiltration with local anaesthetic following appendicectomy in children provides no additional benefit over regular simple analgesia. Its routine use represents dogmatic practise which ought to be challenged for this patient group.


Assuntos
Anestesia Local , Anestésicos Locais , Apendicectomia , Bupivacaína , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Medição da Dor , Dor Pós-Operatória , Cuidados Pós-Operatórios , Estudos Prospectivos
8.
Rheumatology (Oxford) ; 41(3): 279-84, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11934964

RESUMO

OBJECTIVES: A randomized, placebo-controlled, double-blind trial of the relative effectiveness of glucosamine sulphate and placebo in managing pain in osteoarthritis (OA) of the knee. METHODS: Eighty patients with OA of the knee were recruited from a rheumatology out-patient clinic and received either glucosamine sulphate 1500 mg daily for 6 months or dummy placebo. The primary outcome measure was patients' global assessment of pain in the affected knee. RESULTS: Area under the curve analysis for the primary outcome measure showed no difference between placebo and glucosamine [mean difference 0.15 mm, 95% confidence interval (CI) -8.78 to 9.07]. The placebo response was 33%. There was a statistically significant difference between groups in knee flexion (mean difference 13 degrees, 95% CI -23.13 to -1.97), but this difference was small and could have been due to measurement error. CONCLUSIONS: As a symptom modifier in OA patients with a wide range of pain severities, glucosamine sulphate was no more effective than placebo.


Assuntos
Analgésicos/administração & dosagem , Suplementos Nutricionais , Glucosamina/administração & dosagem , Osteoartrite do Joelho/tratamento farmacológico , Dor/prevenção & controle , Adulto , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/fisiopatologia , Medição da Dor , Placebos , Resultado do Tratamento
10.
FASEB J ; 13(9): 1007-24, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10336883

RESUMO

Vitamin C readily scavenges reactive oxygen and nitrogen species and may thereby prevent oxidative damage to important biological macromolecules such as DNA, lipids, and proteins. Vitamin C also reduces redox active transition metal ions in the active sites of specific biosynthetic enzymes. The interaction of vitamin C with 'free', catalytically active metal ions could contribute to oxidative damage through the production of hydroxyl and alkoxyl radicals; whether these mechanisms occur in vivo, however, is uncertain. To examine this issue, we reviewed studies that investigated the role of vitamin C, both in the presence and absence of metal ions, in oxidative DNA, lipid, and protein damage. We found compelling evidence for antioxidant protection of lipids by vitamin C in biological fluids, animals, and humans, both with and without iron cosupplementation. Although the data on protein oxidation in humans are sparse and inconclusive, the available data in animals consistently show an antioxidant role of vitamin C. The data on vitamin C and DNA oxidation in vivo are inconsistent and conflicting, but some of the discrepancies can be explained by flaws in experimental design and methodology. These and other important issues discussed here need to be addressed in future studies of the role of vitamin C in oxidative damage.


Assuntos
Antioxidantes/metabolismo , Ácido Ascórbico/metabolismo , Oxirredução , Animais , Antioxidantes/farmacologia , Ácido Ascórbico/sangue , Ácido Ascórbico/farmacologia , Dano ao DNA/efeitos dos fármacos , Suplementos Nutricionais , Humanos , Metabolismo dos Lipídeos , Oxigenases de Função Mista/efeitos dos fármacos , Oxigenases de Função Mista/metabolismo , Oxirredutases/efeitos dos fármacos , Oxirredutases/metabolismo , Oxigenases/efeitos dos fármacos , Oxigenases/metabolismo , Proteínas/metabolismo
11.
Ann R Coll Surg Engl ; 76(5): 330-1, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7979076

RESUMO

A prospective study of the effectiveness of local anaesthesia in arthroscopy of the knee was performed in 212 consecutive patients. Arthroscopic surgery was undertaken successfully in 121 cases (57%), including meniscectomy and drilling of osteochondral defects. Dynamic evaluation of the patellofemoral joint articulation was possible and demonstration of pathological abnormalities was felt to be beneficial by some patients. The method described is safe, reliable, confers good postoperative analgesia and enables physiotherapy to begin immediately. Conversion to general anaesthesia was necessary in one case due to pain localised to a stiff and osteoarthritic hip. Intra-articular haemorrhage was found to be a problem in one case with synovitis. Only ten patients complained of moderate pain, none had severe pain. Local anaesthesia is contraindicated in cases with ipsilateral osteoarthritis of the hip or with significant synovitis of the knee. This technique is particularly suited to day case surgery.


Assuntos
Procedimentos Cirúrgicos Ambulatórios/métodos , Anestesia Local , Artroscopia/métodos , Articulação do Joelho/cirurgia , Contraindicações , Humanos , Artropatias/diagnóstico , Artropatias/cirurgia , Osteoartrite do Quadril/complicações , Estudos Prospectivos , Sinovite/complicações
12.
J Clin Pharmacol ; 34(1): 48-51, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8132851

RESUMO

The authors examined the efficacy and safety of the combination of verapamil and nifedipine in the control of hypertension. Retrospective analysis of blood pressures was obtained on 50 patients who had historically documented essential hypertension and were receiving verapamil and nifedipine. The patients had moderate to severe hypertension; 27 of 50 (54%) were uncontrolled on prescribed regimens of two or more separate classes of drugs. Control was defined by the ability to maintain a blood pressure of < or = 160/90 by providing doses of verapamil (max: 480 mg/day) and nifedipine (max: 180 mg/day). Twenty-nine (58%) were black and 21 (42%) were white. Ages ranged from 16 to 84 years. Mean duration of therapy was 1-2 years. Only 3 of 50 (6%) were control failures after providing verapamil and nifedipine. Three of 50 (6%) were discontinued because of side effects--reversible hepatitis (2) and rash (1). There were no serious adverse events, i.e., CHF or arrhythmias. Manageable ankle edema was seen in 14 of 50 (28%) patients. Verapamil and nifedipine, a combination of a dihydropyridine and a non-dihydropyridine calcium antagonist, was effective and safe in this group of patients with difficult-to-manage hypertension.


Assuntos
Hipertensão/tratamento farmacológico , Nifedipino/uso terapêutico , Verapamil/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea/efeitos dos fármacos , Quimioterapia Combinada , Edema/induzido quimicamente , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nifedipino/efeitos adversos , Nifedipino/farmacologia , Estudos Retrospectivos , Verapamil/efeitos adversos , Verapamil/farmacologia
14.
Arch Intern Med ; 151(9): 1868-9, 1991 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1888255

RESUMO

In a patient with a gastroplasty, gastric outlet obstruction developed after the dosage of nifedipine GITS (gastrointestinal therapeutic system) was increased from 30 to 60 mg/d. The hard, insoluble shell for this extended-release tablet appears causative.


Assuntos
Bezoares/etiologia , Preparações de Ação Retardada/efeitos adversos , Nifedipino/administração & dosagem , Estômago , Adulto , Feminino , Gastroplastia , Humanos , Nifedipino/uso terapêutico , Comprimidos
15.
Nurs Mirror ; 157(6): 29-30, 1983 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-6554784
16.
Nurs Mirror ; 154(17): 37-9, 1982 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-6919086
19.
J Clin Pharmacol ; 17(1): 13-7, 1977 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-833337

RESUMO

A 20% or greater rise in the fasting blood sugar occurred in 11 of 24 patients treated with 50 mg hydrochlorothiazide twice daily for six to ten weeks. The blood sugar decreased when potassium was given in conjunction with the diuretic, but the mean fasting blood sugar remained higher than pretreatment levels. There was no correlation between the percent change in the blood sugar and the per cent change in the serum K or exchangeable 42K.


Assuntos
Glicemia/metabolismo , Hidroclorotiazida/farmacologia , Potássio/farmacologia , Adulto , Pressão Sanguínea/efeitos dos fármacos , Quimioterapia Combinada , Feminino , Humanos , Hidroclorotiazida/uso terapêutico , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Pessoa de Meia-Idade , Potássio/sangue , Potássio/uso terapêutico
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