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1.
Molecules ; 27(7)2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35408511

RESUMO

The production and use of eco-friendly corrosion inhibitors allows valuable compounds contained in plant waste to be identified and repurposed while reducing the use of polluting synthetic substances. Pectin extracted from Tahiti limes (Citrus latifolia) and King mandarin (Citrus nobilis L.) in addition to natural gums-xanthan gum and latex from the "lechero" plant (Euphorbia laurifolia)-were used to create an eco-friendly corrosion inhibitor. The optimal extraction conditions for pectin were determined from different combinations of pH, temperature, and time in a 23 factorial design and evaluated according to the obtained pectin yield. The highest pectin extraction yields (38.10% and 41.20% from King mandarin and lime, respectively) were reached at pH = 1, 85 °C, and 2 h. Extraction of pectic compounds was confirmed using Fourier-transform infrared spectroscopy, differential scanning calorimetry, and thermogravimetry analyses. Subsequently, a simplex-centroid mixture design was applied to determine the formulation of extracted pectin and natural gums that achieved the highest corrosion inhibitor effect (linear polarization and weight loss methods in NACE 1D-196 saline media using API-5LX52 carbon steel). Impedance spectroscopy analysis showed that the addition of xanthan gum to pectin (formulation 50% pectin-50% xanthan gum) improved the corrosion inhibitor effect from 29.20 to 78.21% at 400 ppm due to higher adsorption of inhibitory molecules on the metal surface.


Assuntos
Citrus , Aço , Carbono/química , Corrosão , Equador , Pectinas/química , Aço/química
2.
Reprod Domest Anim ; 57(7): 701-710, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35253292

RESUMO

Microbial growth in semen may cause a decline of sperm quality and fertility; however, the addition of antifungals to semen extender has been shown to impair the overall fertility of the sperm. The aim of this study was to evaluate the antifungal activity of conventional and natural compounds, and their effect on the motility and kinetics of cooled stallion semen. A total of 15 ejaculates from five stallions were collected using the artificial vagina. Each ejaculate was supplemented with: fluconazole at 12.5 (F1), 25 (F2) and 50 (F3) mg/ml; amphotericin-B at 6.5 (A1), 12.5 (A2) and 25 (A3) mg/ml (A3); clotrimazole at 12.5 (C1), 25 (C2) and 50 (C3) mg/ml; isoespintanol at 50 (I1), 100 (I2) and 150 (I3) µM; thymol at 50 (T1), 100 (T2) and 150 (T3) µM; and a control without supplementation. Motility and kinetics of semen at 0, 24 and 48 hr of cooling at 15°C were assessed using computer-assisted sperm analysis (CASA). At hour 48 of cooling, the antifungal effect of the treatments was evaluated. At hour 0 of cooling, amphotericin-B and I3 showed a reduction in most of the motility and kinetic parameters evaluated (p < .05). These treatments, and also C2 and C3, showed similar results at 24 and 48 hr of cooling. Thymol maintained motility and kinetics of the spermatozoa at all evaluated refrigeration times. Besides, I2 showed a decrease (p < .05) in the colony-forming unit compared to that in the control. It is concluded that thymol and isospintanol could be added as natural antifungals in extenders for stallion semen refrigeration.


Assuntos
Preservação do Sêmen , Anfotericina B/farmacologia , Animais , Antifúngicos/farmacologia , Feminino , Cavalos , Cinética , Masculino , Monoterpenos , Sêmen , Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides , Espermatozoides , Timol/farmacologia
3.
Molecules ; 25(21)2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33139590

RESUMO

Inulin is a polysaccharide of fructose widely used in the food and pharmaceutical industry due to its physicochemical properties and technological applications. Inulin from jicama (Smallanthus sonchifolius) and cabuya (Agave americana) was obtained. The steps for inulin obtention were: raw material preparation, extraction and purification. The extraction conditions were determined using a random design with three levels of stirring speed (0, 130 and 300 rpm), and a 32 factorial experimental design with three levels of temperature (40, 60 and 80 °C) and solid:liquid ratio (1:2, 1:3 and 1:5 S:L). The results showed that the best extractions conditions for jicama were 130 rpm, 75 °C, 1:5 S:L and 25 min; while for cabuya were 80 °C, 300 rpm, 1:5 S-L and 100 min. The weight average molecular weight of inulin from jicama and cabuya were 5799.9 and 4659.75 g/mol, respectively. The identity of the obtained inulin from jicama and cabuya were confirmed by infrared (IR) and Raman spectroscopy. In addition, scanning electron microscopy, differential scanning calorimetry and thermogravimetry analyses were performed to characterize both inulins.


Assuntos
Agave/química , Asteraceae/química , Frutanos/química , Frutanos/isolamento & purificação
4.
Fertil Steril ; 85(5): 1448-51, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16579997

RESUMO

OBJECTIVE: To determine if short courses of metformin (MET) administration in patients with polycystic ovary syndrome (PCOS) would reduce fasting insulin and improve the efficacy of clomiphene citrate (CC) to induce ovulation. DESIGN: A randomized prospective trial involving 31 subjects with PCOS and infertility. SETTING: University-based medical center. PATIENT(S): Obese patients (body mass index > 29 kg/m2) with PCOS. INTERVENTION(S): Patients with PCOS were treated either with CC or CC+MET for 2 weeks. MAIN OUTCOME MEASURE(S): Ovulation as determined by serum P, serum insulin, and total and free T. RESULT(S): In the CC/MET group, a significant increase in sex hormone-binding globulin (SHBG) levels, a decrease in fasting insulin, and an increase in fasting glucose/fasting insulin was detected on day 21 of the cycle. Of these parameters, only SHBG levels increased significantly in the CC group. In the CC/MET group, a significant increase in day 21 progesterone occurred, with 44% of subjects ovulating in the CC+MET group as compared with 6.7% in the CC group. Five subjects in the CC+MET group and none in the CC group conceived. Total and free testosterone levels did not change significantly for either group. CONCLUSION(S): In obese PCOS patients, 2 weeks of MET significantly reduces serum insulin and insulin resistance and increases SHBG levels, resulting in an improved response to CC. This regimen may be beneficial in noncompliant patients or those with intolerance to the side effects of MET.


Assuntos
Clomifeno/administração & dosagem , Metformina/administração & dosagem , Indução da Ovulação/métodos , Ovulação/efeitos dos fármacos , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/tratamento farmacológico , Globulina de Ligação a Hormônio Sexual/análise , Adulto , Esquema de Medicação , Combinação de Medicamentos , Feminino , Fármacos para a Fertilidade Feminina/administração & dosagem , Humanos , Hiperinsulinismo/sangue , Hiperinsulinismo/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Infertilidade/sangue , Infertilidade/tratamento farmacológico , Insulina/sangue , Obesidade/sangue , Obesidade/tratamento farmacológico , Resultado do Tratamento
5.
Dermatol Online J ; 12(7): 25, 2006 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-17459311

RESUMO

An otherwise healthy 5-week-old infant with erythematous plaques predominantly on the face and scalp presented to our dermatology clinic. The mother had been diagnosed with lupus erythematosus 2 years earlier but her disease was quiescent. Neonatal lupus is a rare condition associated with transplacental transfer of IgG anti-SSA/Ro and anti-SSB/La antibodies from the mother to the fetus. Active connective tissue disease in the mother does not have to be present and in fact is often absent. Although the cutaneous, hematologic and hepatic manifestations are transient, the potential for permanent heart block makes it necessary for this to be carefully ruled out. As in this case, the dermatologist may be the one to make the diagnosis and should be aware of the clinical presentation, work-up, and management of this important disease.


Assuntos
Lúpus Vulgar/diagnóstico , Lúpus Vulgar/imunologia , Autoanticorpos/sangue , Autoanticorpos/imunologia , Dermatoses Faciais/imunologia , Feminino , Humanos , Lactente , Transmissão Vertical de Doenças Infecciosas , Lúpus Vulgar/complicações , Lúpus Vulgar/transmissão
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