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1.
Mol Pharm ; 19(1): 26-34, 2022 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-34905926

RESUMEN

The molecular basis of adhesion leading to sticking was investigated by exploring the correlation between thermal analysis and molecular simulations. It is hypothesized that intermolecular interactions between a drug molecule and a punch face are the first step in the adhesion process and the rank order of adhesion during tablet compression should correspond to the rank order of the energies of these interactions. In the present study, the sticking propensity was investigated using ibuprofen, flurbiprofen, and ketoprofen as model substances. At the intermolecular level, a thermal analysis model was proposed as an experimental technique to estimate the work of adhesion between ibuprofen, flurbiprofen, and ketoprofen in a DSC aluminum pan. The linear relationship was established between the enthalpy of vaporization and sample mass to demonstrate the accuracy of the instruments used. The threshold mass for ibuprofen, flurbiprofen, and ketoprofen was determined to be 107, 112, and 222 µg, respectively, after three replicate measurements consistent with the experimental results. Ketoprofen showed a 2-fold higher threshold mass compared to ibuprofen and flurbiprofen, which predicts that ketoprofen should have the highest sticking propensity. Computationally, the rank order of the work of adhesion between ibuprofen, flurbiprofen, and ketoprofen with the metal surface was simulated to be -75.91, 44.75, and -96.91 kcal/mol, respectively, using Materials Studio. The rank order of the interaction between the drug molecule and the iron superlattice decreases in the order ketoprofen > ibuprofen > flurbiprofen. The results indicate that the thermal model can be successfully implemented to assess the sticking propensity of a drug at the molecular level. Also, a new molecular simulation script was successfully applied to determine the interaction energy of the drug molecule upon contact with iron.


Asunto(s)
Comprimidos/química , Adhesividad , Rastreo Diferencial de Calorimetría , Fuerza Compresiva , Flurbiprofeno/química , Ibuprofeno/química , Cetoprofeno/química , Modelos Moleculares
2.
Sensors (Basel) ; 21(7)2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33916287

RESUMEN

The study of cell proliferation is of great importance for medical and biological research, as well as for industrial applications. To render the proliferation process accurately over time, real-time cell proliferation assay methods are required. This work presents a novel real-time and label-free approach for monitoring cell proliferation by continuously measuring changes in thermal properties that occur at the sensor interface during the process. The sensor consists of a single planar resistive structure deposited on a thin foil substrate, integrated at the bottom of a cell culture reservoir. During measurement, the structure is excited with square wave current pulses. Meanwhile, the temperature-induced voltage change measured over the structure is used to derive variations in the number of cells at the interface. This principle is demonstrated first by performing cell sedimentation measurements to quantify the presence of cells at the sensor interface in the absence of cell growth. Later, cell proliferation experiments were performed, whereby parameters such as the available nutrient content and the cell starting concentration were modified. Results from these experiments show that the thermal-based sensor is able to accurately measure variations in the number of cells at the interface. Moreover, the influence of the modified parameters could be observed in the obtained proliferation curves. These findings highlight the potential for the presented thermal method to be incorporated in a standardized well plate format for high-throughput monitoring of cell proliferation.


Asunto(s)
Técnicas de Cultivo de Célula , Proliferación Celular , Fenómenos Físicos
3.
Molecules ; 26(18)2021 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-34576948

RESUMEN

Enantioselective chromatography is one of the most used techniques for the separation and purification of enantiomers. The most important issue for a specific successful enantioseparation is the selection of the suitable chiral stationary phase (CSP). Different synthetic approaches have been applied for the preparation of CSPs, which embrace coating and immobilization methods. In addition to the classical and broadly applied coating and immobilization procedures, innovating strategies have been introduced recently. In this review, an overview of different methods for the preparation of coated and immobilized CSPs is described. Updated examples of CSPs associated with the various strategies are presented. Considering that after the preparation of a CSP its characterization is fundamental, the methods used for the characterization of all the described CSPs are emphasized.

4.
Mikrochim Acta ; 186(12): 850, 2019 11 27.
Artículo en Inglés | MEDLINE | ID: mdl-31776680

RESUMEN

Carbon dots doped with copper(II) and nitrogen (Cu,N@C-dots) were prepared and are shown to be viable fluorescent nanoprobe for pyrogallol (PGL) was developed for the first time. The reaction is based on (a) the complexation reaction between Cu,N@C-dots and catechol moiety, and (b) the generation of a quinone-like structure. Thus, the co-ordination complex formed between Cu(II) in C-dots and PGL results in quenching of the fluorescence of C-dots. In addition, the formation of a yellow color due to complex formation between the nanoprobe and Cu(II) allowed the colorimetric determination of PGL. The nanoprobe was prepared by thermal synthesis, using ethylenediaminetetraacetic acid salt and copper(II) chloride as sources for carbon, nitrogen and copper, respectively. The carbon dots were characterized by UV-VIS spectroscopy, Fourier transform infrared spectroscopy, powder X-ray diffraction, transmission electron microscopy) and dynamic light scattering. Fluorescence drops linearly in the 0.15 to 70 µM PGL concentration range with a detection limit of 39 nM and a relative standard deviation of 1.8%. The optimal excitation and emission wavelengths are 370 nm and 428 nm, respectively. The colorimetric assay has a linear response at 325 nm absorption wavelengths in the 6 to 140 µM PGL concentration range with a detection limit of 1.8 µM and a 2.3% relative standard deviation. Graphical abstractDual mode colorimetric and fluorimetric nanoprobe was designated for pyrolgallol determination based on complexation with copper(II)- and nitrogen-doped carbon dots.

5.
Ginekol Pol ; 87(12): 793-797, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28098936

RESUMEN

OBJECTIVES: Cycle computers are medical devices which use sophisticated statistical methods in addition to a comprehensive on-board database. Their main function is to precisely indicate the fertile and infertile phases of the menstrual cycle, based on daily basal body temperature measurements. A recent medical research program aimed at evaluating the EFFECTIVENESS of cycle computers for contraceptive purposes was conducted. MATERIAL AND METHODS: This study was conducted between May and June 2016 on 3,450 Polish women. The Polish distributor sent an anonymous questionnaire to the participants. To date, 361 women, representing 17,322 cycles have returned accurately completed questionnaires. RESULTS: In the resultant group only 4 unintended pregnancies were observed, resulting in a Pearl index of 0.4989. This suggests that fewer than 5 in 1000 women, who use a cycle computer correctly over a period of one year, may become pregnant unintentionally. This result is slightly better than the results from 2010, when the Pearl index was 0.64. CONCLUSIONS: The results obtained from the study indicate that the effectiveness of cycle computers for contraceptive purposes is comparable with other methods, such as hormonal contraception, and therefore cycle computers can be recommended for women who either cannot use or do not wish to use traditional contraception. These results confirm the effectiveness of using natural fertility symptoms, such as basal body temperature changes in the context of cycle computer technology for the purposes of contraception.


Asunto(s)
Temperatura Corporal , Anticoncepción/métodos , Fertilidad/fisiología , Ciclo Menstrual/fisiología , Métodos Naturales de Planificación Familiar/métodos , Detección de la Ovulación/métodos , Adulto , Conducta Anticonceptiva , Femenino , Humanos , Polonia , Interfaz Usuario-Computador , Adulto Joven
6.
Nanomaterials (Basel) ; 12(14)2022 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-35889723

RESUMEN

In this work, we report a self-assembly method to fabricate a single layer of Co nanorods to study their magnetostatic interaction behavior. The Co nanorods with cambered and flat tips were synthesized by using a solvothermal route and an alcohol-thermal method, respectively. Both of them represent hard magnetic features. Co nanorods with cambered tips have an average diameter of 10 nm and length of 100 nm with coercivity of 6.4 kOe, and flat-tip nanorods with a 30 nm diameter and 100 nm length exhibit a coercivity of 4.9 kOe. They are further assembled on the surface of water in assistance of surfactants. The results demonstrate that the assembly type is dependent on the magnetic induction lines direction. For Co nanorods with flat tips, most of magnetic induction lines are parallel to the length direction, leading to an assembly that is tip to tip. For Co nanorods with cambered tips, they are prone to holding together side by side for their random magnetic induction lines. Under an applied field, the Co nanorods with flat tips can be further aligned into a single layer of Co nanorods. Our work gives a possible mechanism for the magnetic interaction of Co nanorods and provides a method to study their magnetic behavior.

7.
Contraception ; 115: 12-16, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35901971

RESUMEN

OBJECTIVE: The Natural Cycles app employs daily basal body temperature to define the fertile window via a proprietary algorithm and is clinically established effective in preventing pregnancy. We sought to (1) compare the app-defined fertile window of Natural Cycles to that of CycleProGo, an app that uses BBT and cervical mucus to define the fertile window and (2) compare the app-defined fertile windows to the estimated physiologic fertile window. STUDY DESIGN: Daily BBT were entered into Natural Cycles from 20 randomly selected regularly cycling women with at least 12 complete cycles from the CycleProGo database. The proportion of cycles with equivalent (±1 cycle day) fertile-window starts and fertile-window ends was determined. The app-defined fertile windows were then compared to the estimated physiologic fertile window using Peak mucus to estimate ovulation. RESULTS: Fifty seven percent of cycles (136/238) had equivalent fertile-window starts and 36% (72/181) had equivalent fertile-window end days. The mean overall fertile-window length from Natural Cycles was 12.8 days compared to 15.1 days for CycleProGo (p < 0.001). The Natural Cycles algorithm declared 12% to 30% of cycles with a fertile-window start and 13% to 38% of cycles with a fertile-window end within the estimated physiologic fertile window. The CycleProGo algorithm declared 4% to 14% of cycles with a fertile-window start and no cycles with a fertile-window end within the estimated physiologic fertile window. CONCLUSIONS: Natural Cycles designated a higher proportion of cycles days as infertile within the estimated physiologic fertile window than CycleProGo. IMPLICATIONS: Use of cervical mucus in addition to BBT may improve the accuracy of identifying the fertile window. Additional studies with other markers of ovulation and the fertile window would give additional insight into the clinical implications of app-defined fertile window differences.


Asunto(s)
Aplicaciones Móviles , Moco del Cuello Uterino , Femenino , Fertilidad/fisiología , Humanos , Métodos Naturales de Planificación Familiar , Ovulación , Detección de la Ovulación , Embarazo
8.
Environ Sci Pollut Res Int ; 29(27): 40734-40744, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35083673

RESUMEN

A facile soft-template solvent thermal strategy was developed to prepare mesoporous carbon-silica composite (MMCS) by using furfuryl alcohol (FA) as carbon precursor, Pluronic copolymer P123 as template, hydrated iron nitrate as iron source, and teraethylorthosilicate as silicon source and it was applied for the removal of methyl orange (MO). The as-synthesized MMCS with abound of hydrophilic groups processed a high specific surface area, large pore volume, and good magnetic response. With the increased amount of FA, the surface area and functional groups increased, promoting the adsorption effect. The maximum adsorption capacity of MO on MMCS can be high to 113.1 mg g-1 at pH 4 with 150 mg L-1 initial MO concentration. The adsorption isotherm, kinetic, and thermodynamics were all studied and the results showed the adsorption process well fitted Langmuir adsorption isotherm and pseudo-second-order model. Additionally, it was shown that the adsorption process could not be interfered by the co-existence of PO43-, NO3-, CO32-, SO42-, and real water matrix. And the proposed adsorbent can remove MO in three practical water samples with satisfied removal rates ranging from 92.8 to 99.8%. Thus, the MMCS prepared in this study could be utilized as an alternative adsorbent for the removal of methyl orange from practical aqueous solution.


Asunto(s)
Carbono , Contaminantes Químicos del Agua , Adsorción , Compuestos Azo , Concentración de Iones de Hidrógeno , Hierro , Cinética , Fenómenos Magnéticos , Dióxido de Silicio , Solventes , Agua , Contaminantes Químicos del Agua/análisis
9.
Data Brief ; 36: 106987, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33889692

RESUMEN

The data presented in this article are related to the research paper entitled "The circular economy model used in the Polish agro-food consortium: a case study" published in the Journal of Cleaner Production 284 (2021) 124751. The utilisation of meat waste for the production of meat-bone meal is the Farmutil's consortium main activity. The Oxidor system was developed for the combustion of all the odour emitted from meat-bone meal production. This improved the relationship of consortium with the public. Flow-sheet of the unit for thermal oxidation of odour, scheme and image of the thermo-oxidator were presented. The steam produced in the Oxidor system is recycled and re-used for meat-bone meal production. This is an example of new organisational solutions in circular economy originating from a physical flow concept in which energy flows are used as a result of closed-loop recycling.

10.
Bioact Mater ; 6(6): 1541-1554, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33294732

RESUMEN

Iodine ion is one of the most indispensable anions in living organisms, particularly being an important substance for the synthesis of thyroid hormones. Curcumin is a yellow-orange polyphenol compound derived from the rhizome of Curcuma longa L., which has been commonly used as a spice and natural coloring agent, food additives, cosmetics as well as Chinese medicine. However, excess curcumin may cause DNA inactivation, lead to a decrease in intracellular ATP levels, and trigger the tissue necrosis. Therefore, quantitative detection of iodine and curcumin is of great significance in the fields of food and life sciences. Herein, we develop nitrogen-doped fluorescent carbon dots (NCDs) as a multi-mechanism detection for iodide and curcumin in actual complex biological and food samples, which was prepared by a one-step solid-phase synthesis using tartaric acid and urea as precursors without adding any other reagents. An assembled NCDs-Hg2+ fluorescence-enhanced sensor for the quantitative detection of I- was established based on a fluorescence "turn-off-on" mechanism in a linear range of 0.3-15 µM with a detection limit of 69.4 nM and successfully quantified trace amounts of I- in water samples and urine sample. Meanwhile, the as-synthesized NCDs also can be used as a fluorescent quenched sensor for curcumin detection based on the synergistic internal filtration effect (IFE) and static quenching, achieving a good linear range of 0.1-20 µM with a satisfactory detection limit of 29.8 nM. These results indicate that carbon dots are potential sensing materials for iodine and curcumin detection for the good of our health.

11.
Environ Sci Pollut Res Int ; 27(8): 8248-8259, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31900778

RESUMEN

A facile one-pot solvent thermal method was proposed to synthesize magnetic mesoporous carbon (MMC) using Fe(NO3)3·9H2O as a precursor, Pluronic copolymer P123 as template, and chitosan as carbon source, and it was applied for the adsorptive remediation of methyl orange (MO). The characterization results of TEM, XRD, and IR showed that MMC consisted of graphitized carbon matrix and some black spherical particle mixture of Fe3O4 and Fe, and it was rich in hydroxyl and carbonyl groups. Besides, the effect of the content of Fe and the content of chitosan in MMC on the magnetism and adsorption performance of prepared material were investigated. In addition, the effects of pH value, initial concentration of methyl orange, and contact time on the adsorption performance of MO were studied, respectively. At 318 K, the maximum adsorption capacity of MO calculated from Langmuir isotherm was from 139 to 400 mg g-1 on MMC. Kinetic studies demonstrated that the adsorption process obeyed a pseudo-second-order kinetic model. The regeneration experiments revealed that MMC could be reused at least five times without notable decrease of adsorption performance. These results illustrate that MMC is an efficient and economical adsorbent for the adsorption of MO.


Asunto(s)
Compuestos Azo/química , Carbono , Fenómenos Magnéticos , Adsorción , Carbono/química , Concentración de Iones de Hidrógeno , Cinética
12.
ACS Appl Mater Interfaces ; 12(48): 53950-53956, 2020 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-33169978

RESUMEN

Exploration of a new nonlinear optical (NLO)-active functional motif is important in the rational design of promising infrared (IR) NLO materials. Compared with typical tetrahedral MQ4 (M = IIB, III, IV metals; Q = S, Se) motifs, MQ3 (M = As, Sb) pyramids favor high second-harmonic generation (SHG) efficiency while frequently hindering phase matching (PM) because of excessively large optical anisotropy. The surfactant-thermal method was first adopted to achieve PM in MQ3-containing systems and synthesize mixed covalent-ionic IR NLO materials. Two new thioarsenates of AMnAs3S6 (A = Cs, Rb) exhibiting strong PM SHG efficiencies comparable to commercial AGS and laser-induced damage thresholds of one order higher than AGS were obtained. The [As3S6]3- unit in their structures is an unprecedented NLO-active functional motif, which can be useful in designing new IR NLO compounds with large SHG efficiency. In addition, the surfactant-thermal method provides a new general strategy for synthesizing new IR NLO materials.

13.
Environ Sci Pollut Res Int ; 26(12): 12379-12398, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30847816

RESUMEN

Iron oxide, in the form of magnetite (MG)-functionalized porous wollastonite (WL), was used as an adsorbent for heavy metal ions (cadmium and nickel) and oxyanions (chromate and phosphate) removal from water. The porous WL was synthesized from calcium carbonate and siloxane by controlled sintering process using low molecular weight submicrosized poly(methyl methacrylate) as a pore-forming agent. The precipitation of MG nanoparticles was carried out directly by a polyol-medium solvothermal method or via branched amino/carboxylic acid cross-linker by solvent/nonsolvent method producing WL/MG and WL-γ-APS/MG adsorbents, respectively. The structure/properties of MG functionalized WL was confirmed by applying FTIR, Raman, XRD, Mössbauer, and SEM analysis. Higher adsorption capacities of 73.126, 66.144, 64.168, and 63.456 mg g-1 for WL-γ-APS/MG in relation to WL/MG of 55.450, 52.019, 48.132, and 47.382 mg g-1 for Cd2+, Ni2+, phosphate, and chromate, respectively, were obtained using nonlinear Langmuir model fitting. Adsorption phenomena were analyzed using monolayer statistical physics model for single adsorption with one energy. Kinetic study showed exceptionally higher pseudo-second-order rate constants for WL-γ-APS/MG, e.g., 1.17-13.4 times, with respect to WL/MG indicating importance of both WL surface modification and controllable precipitation of MG on WL-γ-APS.


Asunto(s)
Compuestos de Calcio/química , Metales Pesados/química , Modelos Químicos , Silicatos/química , Adsorción , Cadmio , Compuestos Férricos , Óxido Ferrosoférrico , Iones , Cinética
14.
MethodsX ; 5: 1613-1617, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30568882

RESUMEN

This paper describes a thermal method to obtain metal oxides on a titanium substrate surface. This adapted Pechini method is a versatile, easy to handle and scalable technique to obtain electrodes for industrial uses, such as Dimensionally Stable Anodes (DSA). This method has advantages over other thermal methods like dip coating or sputtering, as it needs a smaller amount of polymeric mixture than dip coating method to cover the same area and is less expensive than sputtering method. The thermal method described herein to prepare DSA type electrodes of RuO2-ZrO2 doped with Sb2O5 over titanium plates needs no sophisticated equipment as spray pyrolysis technique does; a muffle, ultrasonic equipment, and a hot plate magnetic stirrer are the principal apparatus necessary to carry out the adapted Pechini method. On the other hand, this method allows metal oxides to disperse homogeneously. The cyclic voltammograms showed the stability of DSA, and the accelerated life test allowed establishing its useful life (18.18 years) at a current density of 10 mA cm-2.

15.
J Colloid Interface Sci ; 486: 128-135, 2017 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-27697650

RESUMEN

We reported the design and synthesis of mixed ligands Cu-metal organic frameworks (MOFs), MOFs-2 and MOFs-3, and their application as the transport vehicles for the delivery of Ibuprofen (IBU) and doxorubicin hydrochloride (DOX). The unique MOFs with mixed ligands, 1,3,5-benzene tricarboxylate (BTC) and isophthalic acid (IPA), were easily prepared by hydro-thermal method, and their structures were well characterized by XRD, FTIR, and SEM imaging analysis. Single ligand MOFs with BTC or IPA only were also prepared and characterized as the control group. The biocompatibility of synthesized MOFs towards human cells, HEK 293A was evaluated by MTT assay. To demonstrate the practical applications of the prepared MOFs as the transport vehicles for drugs, the capability of loading and controlled release of IBU and DOX by MOFs-1, MOFs-2, MOFs-3, and MOFs-4 were then examined. In addition, the drug delivery efficiency of various MOFs with different ligands was investigated.


Asunto(s)
Cobre/química , Portadores de Fármacos , Compuestos Organometálicos/síntesis química , Agua/química , Antiinflamatorios no Esteroideos/química , Antiinflamatorios no Esteroideos/farmacología , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacología , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/química , Doxorrubicina/farmacología , Composición de Medicamentos , Liberación de Fármacos , Células HEK293 , Calor , Humanos , Concentración de Iones de Hidrógeno , Ibuprofeno/química , Ibuprofeno/farmacología , Cinética , Ácidos Ftálicos/química , Ácidos Tricarboxílicos/química
16.
Front Public Health ; 5: 42, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28349048

RESUMEN

PURPOSE: Birth control is a persistent global health concern. Natural family planning (NFP) comprises methods to achieve or avoid pregnancy independent of mechanical or pharmacological intervention. The sympto-thermal method (STM) of NFP employs daily observation of cervical fluids and measurement of basal body temperature. This multi-country study was undertaken to describe the characteristics of STM users, understand their perceptions of NFP, and its perceived impact on relationships. METHODS AND RESULTS: Questionnaires for women and men were developed in German and translated to English, Polish, Italian, Czech, and Slovak by native speakers. A total of 2,560 respondents completed the online questionnaire (37.4% response). Participants were married (89%) and well educated, and their self-perceived financial status was described as "good" or "very good" by 65% of the respondents. Forty-seven percent had previously used contraceptives. Ninety-five percent of women and 55% of men said using NFP has helped them to know their body better. Large majorities of men (74%) and women (64%) felt NFP helped to improve their relationship while <10% felt use of NFP had harmed their relationship. Most women (53%) and men (63%) felt using NFP improved their sex life while 32% of women and 24% of men felt it was unchanged from before they used NFP. Seventy-five percent of women and 73% of men said they are either "satisfied" or "very satisfied" with their frequency of sexual intercourse. CONCLUSION: This survey demonstrates STM of NFP is a well-accepted approach to family planning across several Western cultures. It is consistently viewed as being beneficial to couples' self-knowledge, their relationship, and satisfaction with frequency of sexual intercourse.

17.
Open Biomed Eng J ; 9: 75-82, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25893018

RESUMEN

Hydroxyapatite Ca10(PO4)6(OH)2 (HAp) and calcium phosphate ceramic materials and coatings are widely used in medicine and dentistry because of their ability to enhance the tissue response to implant surfaces and promote bone ingrowth and osseoconduction processes. The deposition conditions have a great influence on the structure and biofunctionality of calcium phosphate coatings. Corrosion processes and poor adhesion to substrate material reduce the lifetime of implants with calcium phosphate coatings. The research has focused on the development of advanced methods to deposit double-layered ceramic oxide/calcium phosphate coatings by a hybrid technique of magnetron sputtering and thermal methods. The thermal method can promote the crystallization and the formation of HAp coatings on titanium alloy Ti6Al4V substrates at low temperature, based on the principle that the solubility of HAp in aqueous solutions decreases with increasing substrate temperature. By this method, hydroxyapatite directly coated the substrate without precipitation in the initial solution. Using a thermal substrate method, calcium phosphate coatings were prepared at substrate temperatures of 100-105 (o)C. The coated metallic implant surfaces with ceramic bond coats and calcium phosphate layers combine the excellent mechanical properties of metals with the chemical stability of ceramic materials. The corrosion test results show that the ceramic oxide (alumina) coatings and the double-layered alumina-calcium phosphate coatings improve the corrosion resistance compared with uncoated Ti6Al4V and single-layered Ti6Al4V/calcium phosphate substrates. In addition, the double-layered alumina/hydroxyapatite coatings demonstrate the best biocompatibility during in vitro tests.

18.
Fertil Steril ; 39(5): 647-55, 1983 May.
Artículo en Inglés | MEDLINE | ID: mdl-6840308

RESUMEN

The intra- and interwoman variation in nine physiologic or biochemical indices of the fertile period has been studied over 58 menstrual cycles from 13 experienced users of the symptothermal method of family planning by periodic abstinence. The time and duration of a possible fertile period have been determined by five methods (symptothermal, cervical mucus, basal body temperature plus calendar calculation, defined changes in the concentration of estrone-3-glucuronide and the ratio of estrone-3-glucuronide to pregnanediol-3 alpha-glucuronide as determined by immunochemical tests on daily samples of early morning urine). The values were compared with a period of probable fertility (day of urinary luteotropin [LH] peak -3 to day of LH peak +2). The duration of the possible fertile period by each method (mean +/- standard deviation) was 13.4 (2.9), 11.9 (2.9), 11.8 (3.3), 9.3 (2.2), and 10.9 (2.3) days, respectively, while the percentage of the probable fertile periods covered entirely by each approach was 98%, 91%, 90%, 83%, and 84%, respectively. The results warrant the initiation of clinical trials to ascertain the practical value of the individual or combined tests for family planning and the management of infertility.


PIP: The intra- and interwoman variation in 9 physiologic or biochemical indices of the fertile period has been studied over 58 menstrual cycles from 13 experienced users of the symptothermal method of family planning by periodic abstinence. The time and duration of a possible fertile period have been determined by 5 methods: 1) symptothermal, 2) cervical mucus, 3) basal body temperature plus calendar calculation, and 5) defined changes in the concentration of estrone-3-glucuronide and the ratio of estrone-3-glucuronide to pregnamediol-3-alpha-glucuronide as determined by immunochemical tests on daily samples of early morning urine. The values were compared with a period of probable fertility. The duration of the possible fertile period by each method (mean +or- standard deviation) was 13.4 (2.9), 11.9 (2.9), 11.8 (3.3), 9.3 (2.2), and 10.9 (2.3) days, respectively, while the percentage of the probable fertile periods covered entirely by each approach was 98%, 91%, 90%, 83%, and 84%, respectively. The results warrant the initiation of clinical trials to ascertain the practical value of the individual or combined tests for family planning and the management of infertility.


Asunto(s)
Detección de la Ovulación/métodos , Adulto , Temperatura Corporal , Moco del Cuello Uterino/análisis , Estradiol/análisis , Estrona/análogos & derivados , Estrona/análisis , Femenino , Humanos , Hormona Luteinizante/análisis , Menstruación , Pregnanodiol/análogos & derivados , Pregnanodiol/análisis , Radioinmunoensayo , Factores de Tiempo
19.
Fertil Steril ; 38(1): 117-8, 1982 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7095160

RESUMEN

PIP: 22 physician-providers who serve natural family planning (NFP) programs, mostly in the private sector, gathered to formulate a standard terminology for the field. The Billings and sympto-thermal methods are the 2 methods taught by this group. The sypto-thermal method helps a woman predict ovulation by detecting changes in her cervical mucus and in the cervix itself. Ovulation is confirmed by monitoring the temperature shift as well as by observing the cessation of mucus buildup, closing of the cervix, and firmness of the os. Those women using the Billings ovulation method predict fertility by the appearance of the cervical mucus, its sensation, color, and elasticity. Sperm will only survive if the cervical mucus is of the fertile type. It is also helpful to recognize mucus patterns of anovulation during breastfeeding, weaning, and premenopause. Use-effective rates which only reflect pregnancy are inadequate in evaluating NFP. A series of definitions are presented which in the future will help to analyze NFP data to accurately reflect NFP effectiveness. The terms included are: total pregnancies, planned pregnancy rate, pregnancy avoidance, method effectiveness rate, method-related pregnancies, informed choice pregnancies, teaching-related pregnancies, and unresolved pregnancies. All NPF teaching programs include instruction in basic reproductive physiology and in the recognition of the fertile phase. The cervical mucus factor is emphasized in ovulation method groups while thermal and other parameters are given equal weight in the sympto-thermal groups. It is the intent of NPF to teach couples to distinguish the fertile phase by using the fertility markers and to have them integrate this information into their sexual decision making. Success is dependent on teacher skill and the ability to inspire confidence in the method. Recognition of the mucus patterns of ovulation and anovulation are crucial in assessing infertility. All family providers under Title 10 must by law offer either NFP instruction or referrals to sites which do. A directory of non-Title 10 providers of NFP Services is available for $4.00 from the Human Life and NFP Foundation, 205 South Patrick Street, Alexandria, Virginia, 22314.^ieng


Asunto(s)
Curriculum , Servicios de Planificación Familiar/tendencias , Terminología como Asunto , Financiación Gubernamental , Métodos , Médicos , Enseñanza , Estados Unidos
20.
Fertil Steril ; 45(3): 334-7, 1986 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3949032

RESUMEN

Sixty basal body temperature (BBT) charts were reviewed by three reproductive endocrinologists in an attempt retrospectively to predict the urinary luteinizing hormone (LH) surge. LH surges had been previously detected in all cycles with the use of a commercially available monoclonal antibody kit, Ovustick (Monoclonal Antibodies, Inc., Mountain View, CA). Surges were correctly predicted to the day (day 0) 18.3% to 30.0% of the time, to within 1 day on either side of day 0 56.7% to 70.0% of the time, to within 2 days 83.3% to 98.3% of the time, and to within 3 days 96.7% to 98.3% of the time. The BBT remains an inaccurate predictor of the day of the LH surge but does provide a reasonably accurate guide to the 2- to 3-day period on either side of the surge.


PIP: The accuracy of basal body temperature (BBT) in retrospectively predicting the urinary luteinizing hormone (LH) surge was assessed in 60 cycles from 21 women undergoing artificial insemination with their husbands' semen. LH surges previously had been detected through use of commercially available monoclonal antibody kit, Ovustick. BBT charts were reviewed by 3 reproductive endocrinologists. Surges were correctly predicted to the day 18.3-30.0% of the time, to within 1 day on either side of day 0 56.7-70.0% of the time, to within 2 days 83.3-98.3% of the time, and to within 3 days 96.7-98.3% of the time. In addition, the physician who performed the inseminations calculated the relationship between the thermal nadir and the urinary LH surge. The nadir was noted on the day of the surge in 30% of cycles, between days -1 and +1 in 78.3%, and between days -2 and +2 in 100%. The results confirm the impression that the BBT is an inaccurate predictor of the precise day of the LH surge. On the other hand, it does provide a reasonably accurate guide to the 2-3 day period on either side of the LH surge. It is concluded that prospective use of the BBT, in which the endpoint for identifying the LH surge is the lowest temperature at midcycle before a sustained rise, can be useful in timing artificial insemination if multiple inseminations at 48-hour intervals are feasible.


Asunto(s)
Temperatura Corporal , Hormona Luteinizante/orina , Femenino , Humanos , Inseminación Artificial Homóloga , Ciclo Menstrual , Detección de la Ovulación/métodos , Juego de Reactivos para Diagnóstico/normas
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