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Background: With the ever-increasing integration of artificial intelligence (AI) into health care, it becomes imperative to gain an in-depth understanding of how health care professionals, specifically nurse practitioners, perceive and approach this transformative technology. Objectives: This study aimed to gain insights into nurse practitioners' perceptions and attitudes toward AI adoption in health care. Methods: This qualitative research employed a descriptive and phenomenological approach using in-depth interviews. Data were collected through a semi-structured questionnaire with 37 nurse practitioners selected through purposive sampling, specifically Maximum Variation Sampling and Expert Sampling techniques, to ensure diversity in characteristics. Trustworthiness of the research was maintained through member checking and peer debriefing. Thematic analysis was employed to uncover recurring themes and patterns in the data. Results: The thematic analysis revealed nine main themes that encapsulated nurse practitioners' perceptions and attitudes toward AI adoption in health care. These included nurse practitioners' perceptions of AI implementation, attitudes toward AI adoption, patient-centered care and AI, quality of health care delivery and AI, ethical and regulatory aspects of AI, education and training needs, collaboration and interdisciplinary relationships, obstacles in integrating AI, and AI and health care policy. While this study found that nurse practitioners held a wide range of perspectives, with many viewings AI as a tool to enhance patient care. Conclusions: This research provides a valuable contribution to the evolving discourse surrounding AI adoption in health care. The findings underscore the necessity for comprehensive education and training in AI, accompanied by clear and robust ethical and regulatory guidelines to ensure the responsible integration of AI in health care practice. Furthermore, fostering collaboration and interdisciplinary relationships is pivotal for the successful incorporation of AI in health care. Policymakers should also address the challenges and opportunities that AI presents in the health care sector. This study enhances the ongoing conversation on AI adoption in health care by shedding light on the perspectives of nurses, thereby shaping future strategies for AI integration.
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Childhood experiences are known to shape individuals' development and can influence various aspects of life later on. Understanding the long-term effects is crucial for informing interventions and policies aimed at promoting healthy aging. This review aimed to explore the long-term effects of childhood experiences on older individuals. This systematic review comprised three distinct phases. Firstly, a systematic review was conducted, exploring databases such as Google Scholar, PubMed, EMBASE, PsycINFO, and the Web of Science. Out of the 2116 studies initially identified, 24 studies were selected based on the inclusion criteria. Secondly, these inclusion criteria were applied to ensure that the chosen studies specifically delved into the connection between childhood experiences and outcomes in older individuals. Finally, data extraction and synthesis techniques were employed to analyze findings, facilitating the drawing of conclusions concerning the enduring impacts of childhood experiences on the well-being of older individuals. The review's findings revealed how negative experiences in childhood continue to affect older individuals in various ways. These early-life events have far-reaching consequences, profoundly impacting their physical health, making them more susceptible to chronic diseases and weakening their immune system. Additionally, they affect mental health, leading to conditions like depression, anxiety, and substance abuse. Cognitive function is also affected, resulting in memory problems and cognitive decline. Furthermore, these experiences impact social relationships, affecting trust, emotional control, and social isolation in later life. This review highlighted the enduring influence of childhood circumstances on the health and well-being of older individuals. Policymakers and health care practitioners should consider these findings when developing strategies to support healthy aging and mitigate the long-term effects of adverse childhood experiences.
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With ever-increasing plastic waste, a robust and sustainable methodology to valorize the waste and tweak, the composition of the value added product is the need of the hour. The present study describes the effect of different heterogeneous catalyst systems on the yield, composition and nature of the pyrolysis oil produced from various waste polyolefins like high-density polyethylene (HDPE), linear low-density polyethylene (LLDPE), and polypropylene (PP). The waste polyolefins were subjected to thermal as well as catalytic pyrolysis. Liquid, gas, and solid products were obtained during the pyrolysis. Various catalysts such as activated alumina (AAL), ZSM-5, FCC catalyst, and halloysite clay (HNT) were used. Usage of catalysts has reduced the temperature of the pyrolysis reaction from 470 to 450 °C with better liquid product yield. PP waste generated higher liquid yield compared to LLDPE and HDPE waste. The highest liquid yield of 70.0% was achieved with PP waste using AAL catalyst at 450 °C. The sulfur and chloride content was found to be < 10 and < 20 ppm respectively in all the pyrolysis liquid. Pyrolysis liquid products were analyzed using gas chromatography (GC), nuclear magnetic resonance (NMR) spectroscopy, Fourier-transform infrared (FTIR) spectroscopy, X-ray fluorescence (XRF) spectroscopy, and gas chromatography coupled with mass spectrophotometry (GC-MS). The obtained liquid products consist of paraffin, naphthene, olefin and aromatic components. Catalyst regeneration experiments with AAL showed that the product distribution profile remains the same up to three cycles of regeneration.
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Plásticos , Polietileno , Polietileno/química , Pirólisis , Polienos , Polipropilenos/química , Arcilla , CatálisisRESUMEN
A series of derivatives of the 4,5-disubstituted class of 2-deoxystreptamine aminoglycoside antibiotics neomycin, paromomycin, and ribostamycin was prepared and assayed for (i) their ability to inhibit protein synthesis by bacterial ribosomes and by engineered bacterial ribosomes carrying eukaryotic decoding A sites, (ii) antibacterial activity against wild type Gram negative and positive pathogens, and (iii) overcoming resistance due to the presence of aminoacyl transferases acting at the 2'-position. The presence of five suitably positioned residual basic amino groups was found to be necessary for activity to be retained upon removal or alkylation of the 2'-position amine. As alkylation of the 2'-amino group overcomes the action of resistance determinants acting at that position and in addition results in increased selectivity for the prokaryotic over eukaryotic ribosomes, it constitutes an attractive modification for introduction into next generation aminoglycosides. In the neomycin series, the installation of small (formamide) or basic (glycinamide) amido groups on the 2'-amino group is tolerated.
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Aminoglicósidos/síntesis química , Aminoglicósidos/farmacología , Antibacterianos/síntesis química , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Ribosomas/efectos de los fármacos , Sitios de Unión , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Hexosaminas , Humanos , Pruebas de Sensibilidad Microbiana , Neomicina/química , Neomicina/farmacología , Paromomicina/química , Paromomicina/farmacología , Biosíntesis de Proteínas/efectos de los fármacos , Ribosomas/metabolismo , Relación Estructura-ActividadRESUMEN
In this study, commercial surfactants have been investigated at economically viable dosage to enhance the enzymatic saccharification of pretreated wheat straw at high solid loadings. Twenty one surfactants were evaluated with pilot scale pretreated wheat straw and mechanism of surfactant action has been elucidated. One surfactant has improved the saccharification of dilute acid wheat straw (DAWS) by 26.4% after 24h and 23.1% after 48h while, steam exploded wheat straw (SEWS) saccharification was increased by 51.2% after 24h and 36.4% after 48h at 10% solid loading. At 20% solid loading, about 31% increase in yield was obtained on DAWS and about 55% on SEWS after 48h. Further, lignin was isolated from pretreated wheat straws and characterized which revealed that SEWS derived lignin was more hydrophobic than DAWS lignin. This investigation suggests that surfactant supplementation during saccharification is an effective strategy to achieve higher saccharification yield.
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Metabolismo de los Hidratos de Carbono/efectos de los fármacos , Celulasa/metabolismo , Lignina/metabolismo , Tensoactivos/farmacología , Triticum/química , Residuos , Adsorción , Biomasa , Reactores Biológicos , Estabilidad de Enzimas/efectos de los fármacos , Fermentación/efectos de los fármacos , Proyectos Piloto , Espectroscopía de Protones por Resonancia Magnética , Reproducibilidad de los Resultados , Espectroscopía Infrarroja por Transformada de Fourier , Vapor , Especificidad por Sustrato/efectos de los fármacos , Ácidos Sulfúricos/farmacologíaRESUMEN
A stereocontrolled approach for the construction of a highly functionalized bicyclo[3.2.0]heptane derivative embodying the bridged lactone present in the diterpene bielschowskysin is reported. The key step involves a stereoselective Cu(I)-catalyzed [2 + 2] photocycloaddition of a 1,6-diene embedded in a sugar derivative.
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Compuestos Bicíclicos con Puentes/química , Diterpenos/síntesis química , Heptanos/química , Diterpenos/química , Conformación Molecular , EstereoisomerismoRESUMEN
The effect of a 4,6-O-alkylidene acetal on the rate of acid-catalyzed hydrolysis of methyl galactopyranosides and of spontaneous hydrolysis of 2,4-dinitrophenyl galactopyranosides has been studied through the synthesis and hydrolysis of analogs in which O6 is replaced by a methoxymethylene unit in which the methoxy group adopts either an equatorial or an axial position according to the configuration. Consistent with earlier studies under both acid-catalyzed and spontaneous hydrolysis conditions, the alkylidene acetal, or its 7-carba analog, retards hydrolysis with respect to comparable systems lacking the cyclic protecting group. The configuration at C6 in the 7-carba analogs does not influence the rate of acid-catalyzed hydrolysis but has a minor influence on the rate of spontaneous hydrolysis of the 2,4-dinitrophenyl galactosides, confirming earlier studies on the role played by the hydroxymethyl group conformation on glycoside reactivity. The benzylidene acetal is found to stabilize the α-anomer of galactopyranose derivatives relative to monocyclic analogs. Reasons for the α-selectivity of 4,6-O-benzylidene-protected galactopyranosyl donors bearing neighboring group-active protecting groups at O2 are discussed.
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Acetales/química , Galactosa/análogos & derivados , Galactosa/química , Galactosa/síntesis química , Hidrólisis , Cinética , Conformación Molecular , Estereoisomerismo , Relación Estructura-ActividadRESUMEN
An asymmetric synthesis of C(10)-epi-dihydro-epi-deoxy arteannuin B is reported employing an IMDA reaction of sugar embedded decatrienone. During this investigation it has been demonstrated that changing the position of the methyl group on the diene moiety changes the stereochemical outcome leading to access to either cis- or trans-decalin derivatives exclusively.
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Artemisininas/síntesis química , Carbono/química , Modelos Moleculares , Estructura Molecular , EstereoisomerismoRESUMEN
Cu(I)-catalysed [2 + 2] photocycloaddition of 1,6-dienes embedded in a furano sugar is described in connection to a synthetic approach to an abnormal marine prostanoid tricycloclavulone. An unprecedented influence of remote substituents on the reactivity and stereoselectivity of the photocycloaddition reaction has been uncovered during this investigation. While an alkene substituent inhibits cycloaddition through steric effects, a substituent having a hydroxyl or alkoxy group at the same location facilitates cycloaddition exclusively from its own side. This investigation has led to the synthesis of a functionalised 5,4-fused core unit of tricycloclavulone.
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Cobre/química , Prostaglandinas/síntesis química , Catálisis , Ciclización , Dimerización , Estructura Molecular , Procesos Fotoquímicos , EstereoisomerismoRESUMEN
Recent broad-ranging mechanistic studies of FeIII-TAML peroxide activators enable a strategy for designing catalysts with improved (i) hydrolytic and (ii) operational stabilities, (iii) faster activation of H2O2 and other peroxides, and (iv) a pH of highest activity closer to 7. Combining all items of insight leads to [Fe{1-NO2C6H3-3,4-(NCOCMe2NCO)2CF2}(OH2)]- (1a) which exhibits the most desirable technical performance in its class.
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Compuestos Férricos/química , Lactamas Macrocíclicas/química , Peróxidos/química , Catálisis , Peróxido de Hidrógeno/química , Concentración de Iones de Hidrógeno , Cinética , Modelos MolecularesRESUMEN
OBJECTIVE: To determine the effect of zinc supplementation on diarrheal incidence and to discover any operational constraints of zinc supplementation at the community level. METHODS: We included 1712 children aged between 6 and 48 months in a randomized double blind study in rural area comprising of 11 villages. Children were randomly divided into 2 groups. Zinc/placebo syrup supplementation was continued for 6 months in a weekly schedule from May 2003. Children were followed up weekly for detection of diarrhea from May 2003 until April 2004. Around 30% of the study children were evaluated every 2 months during supplementation period. RESULTS: During the period, 80,534 weekly visits were made giving 1548.73-child years of observation. We detected 1438 diarrheal episodes among 846 children. The incidence of diarrhea was significantly less during the supplemented period (P < 0.001; RR 0.74 (0.64-0.87)) in the zinc group. A significant difference was also noted during the follow up period (P < 0.05). In the zinc group, children <2 years of age had significantly less diarrhea during supplementation and the follow up period. Multiple episodes of diarrhea (>or=2) were significantly less in the zinc group. Approximately 85% of the surveillance workers made weekly visits to the houses and 96% of mothers administered syrup weekly to their children. Around 80% of mother's were aware of the possible benefits of zinc supplementation. CONCLUSION: Weekly zinc supplementation was effective in reducing diarrheal morbidity at the community level and it was operationally feasible.
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Atención a la Salud , Diarrea/epidemiología , Suplementos Dietéticos , Población Rural , Zinc/administración & dosificación , Zinc/uso terapéutico , Preescolar , Diarrea/prevención & control , Método Doble Ciego , Esquema de Medicación , Femenino , Humanos , Incidencia , India/epidemiología , Lactante , Masculino , MorbilidadRESUMEN
Iron(V)-oxo species have been proposed as key reactive intermediates in the catalysis of oxygen-activating enzymes and synthetic catalysts. Here, we report the synthesis of [Fe(TAML)(O)]- in nearly quantitative yield, where TAML is a macrocyclic tetraamide ligand. Mass spectrometry, Mössbauer, electron paramagnetic resonance, and x-ray absorption spectroscopies, as well as reactivity studies and density functional theory calculations show that this long-lived (hours at -60 degrees C) intermediate is a spin S = 1/2 iron(V)-oxo complex. Iron-TAML systems have proven to be efficient catalysts in the decomposition of numerous pollutants by hydrogen peroxide, and the species we characterized is a likely reactive intermediate in these reactions.
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Compuestos de Hierro/química , Compuestos Macrocíclicos/química , Catálisis , Fenómenos Químicos , Química Física , Espectroscopía de Resonancia por Spin del Electrón , Ligandos , Conformación Molecular , Oxidación-Reducción , Espectrometría de Masa por Ionización de Electrospray , Espectroscopía de Mossbauer , Análisis Espectral , Rayos XRESUMEN
Small-molecule synthetic homogeneous-oxidation catalysts are normally poorly protected from self-destruction under operating conditions. Achieving design control over both activity and half-life is important not only in advancing the utility of oxidation catalysts, but also in minimizing hazards associated with their use and disposal. Iron(III)-TAML (tetraamido-macrocyclic ligand) oxidant catalysts rapidly activate H(2)O(2) for numerous significant processes, exhibiting high and differing activity and varying half-lives depending upon the TAML design. A general approach is presented that allows for the simultaneous determination of the second-order rate constant for the oxidation of a targeted substrate by the active catalyst (k(II)) and the rate constant for the intramolecular self-inactivation of the active catalyst (k(i)). The approach is valid if the formation of the active catalyst from its resting state and the primary oxidizing agent, measured by the second-order rate constant k(I), is fast and the catalyst concentration is very low, such that bimolecular inactivation pathways can be neglected. If the oxidation process is monitored spectrophotometrically and is set up to be incomplete, the kinetic trace can be analyzed by using the equation ln(lnA(t))/A(infnity)=ln(k(II)/k(i)[Fe(III)](tot)-k(i)t, from which k(II) and k(i) can be determined. Here, A(t) and A(infinity) are absorbances at time t and at the end of reaction (t=infinity), respectively, and [Fe(III)](tot) is the total catalyst concentration. Several tools were applied to examine the validity of the approach by using a variety of different Fe(III)-TAML catalysts, H(2)O(2) and tBuOOH as oxidizing agents, and the dyes safranine O and orange II as target substrates. Learning how catalyst activities (k(II)) and catalyst half-lives (k(i)) can be controlled by ligand design is an important step in creating green catalysts that will not persist in the environment after they have achieved their purpose.
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The effect of sterically encumbering ligands on the electronic structure of oxomolybdenum tetrathiolate complexes was determined using a combination of electronic absorption and magnetic circular dichroism spectroscopies, complimented by DFT bonding calculations, to understand geometric and electronic structure contributions to reduction potentials. These complexes are rudimentary models for a redox-active metalloenzyme active site in a protein matrix and allow for detailed spectroscopic probing of specific oxomolybdenum-thiolate interactions that are directly relevant to Mo-S(cysteine) bonding in pyranopterin molybdenum enzymes. Data are presented for three para-substituted oxomolybdenum tetrathiolate complexes ([PPh4][MoO(p-SPhCONHCH3)4], [PPh4][MoO(p-SPhCONHC(CH2O(CH2)2CN)3)4], and [PPh4][MoO(p-SPhCONHC(CH2O(CH2)2COOCH2CH3)3)4]). The Mo(V/IV) reduction potentials of the complexes in DMF are -1213, -1251, and -1247 mV, respectively. The remarkably similar electronic absorption and magnetic circular dichroism spectra of these complexes establish that the observed reduction potential differences are not a result of significant changes in the electronic structure of the [MoOS4]- cores as a function of the larger ligand size. We provide evidence that these reduction potential differences result from the driving force for a substantial reorganization of the O-Mo-S-C dihedral angle upon reduction, which decreases electron donation from the thiolate sulfurs to the reduced molybdenum center. The energy barrier to favorable O-Mo-S-C geometries results in a reorganizational energy increase, relative to [MoO(SPh)4](-/2-), that correlates with ligand size. The inherent flexible nature of oxomolybdenum-thiolate bonds indicate that thiolate ligand geometry, which controls Mo-S covalency, could affect the redox processes of monooxomolybdenum centers in pyranopterin molybdenum enzymes.
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Molibdeno/química , Compuestos Organometálicos/química , Compuestos de Sulfhidrilo/química , Dicroismo Circular , Proteínas Hierro-Azufre/química , Modelos Moleculares , Conformación Molecular , Oxidación-Reducción , Oxidorreductasas/química , Teoría Cuántica , Espectrofotometría Infrarroja , Espectrofotometría Ultravioleta , Sulfito-Oxidasa/química , Xantina OxidasaRESUMEN
OBJECTIVE: To assess the impact of zinc supplementation on diarrheal morbidity and growth pattern of low birth weight (LBW) infants. METHODOLOGY: In a randomized, double-blind, placebo-controlled, community-based study conducted in the Tiljala slum of eastern Kolkata, India, between 1999 and 2001, a birth cohort of 100 LBW infants was randomly allocated into either an intervention group receiving 1 mL daily dose of 5 mg of elemental zinc as zinc sulfate in vitamin B complex-based syrup or a placebo group receiving an identical placebo of 1 mL of vitamin-based syrup from birth up to 1 completed year of age. Active weekly surveillance was conducted for detection of diarrhea. Anthropometric measurements of each child were recorded once every month as close to the child's birth date as possible. Data were analyzed by using statistical software packages SPSSPC+ 4.0 (SPSS, Inc, Chicago, IL) and Epi Info 6.0 (Centers for Disease Control and Prevention, Atlanta, GA). RESULTS: Among the zinc-supplemented group, diarrheal incidence of 1.36 episodes per child per year were observed, whereas it was 1.93 episodes per child per year among the placebo group, giving a relative risk of 1.4 (95% confidence interval: 1.02-2.00). Linear growth and weight for age showed significant differences between the supplemented and placebo groups only at the end of 1 year. Interestingly, the impact of zinc supplementation was masked to a large extent by the protective action of breastfeeding. CONCLUSIONS: The study showed that zinc supplementation had a beneficial impact on the incidence of diarrhea and also weight gain among LBW infants.
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Diarrea Infantil/epidemiología , Suplementos Dietéticos , Recién Nacido de Bajo Peso/crecimiento & desarrollo , Zinc , Antropometría , Método Doble Ciego , Humanos , India/epidemiología , Lactante , Recién Nacido , Morbilidad , Factores SocioeconómicosRESUMEN
The mononuclear monooxomolybdenum(VI) complex hydrotris(3,5-dimethyl-1-pyrazolyl)borato(bis-4-ethoxyphenolato)oxomoylybdenum(VI) cation, [LMoVIO(p-OC6H4-OC2H5)2]+, where L- = hydrotris(3,5-dimethyl-1-pyrazolyl)borate, has been synthesized by chemical and electrochemical oxidation from the corresponding neutral oxomolybdenum(V) species, LMoVO(p-OC6H4-OC2H5)2. The molybdenum(VI) species has been characterized by NMR, IR, and resonance Raman spectroscopies, mass spectrometry, and electronic spectroscopy. Acetonitrile solutions of cationic [LMoVIO(p-OC6H4-OC2H5)2]+ react with tertiary phosphines (PR3) to generate phosphineoxide-bound adducts, [LMoIV(OPR3)(p-OC6H4-OC2H5)2]+, which subsequently generate the cationic desoxo species, [LMoIV(p-OC6H4-OC2H5)2]+ and OPR3. In the presence of water and an oxidizing agent the desoxo species generates the monooxomolybdenum(V), LMoVO(p-OC6H4-OC2H5)2, and completes the catalytic cycle. The oxygen atom transfer reaction has been probed by isotope-labeling experiments, vibrational spectroscopies, and mass spectrometry. This study describes an analogue complex that can exhibit all important processes of the catalytic cycle involving monooxomolybdenum(VI) and desoxomolybdenum(IV) centers.
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Molibdeno/química , Compuestos Organometálicos/síntesis química , Sitios de Unión , Catálisis , Compuestos Organometálicos/química , Oxidación-Reducción , Espectrometría de Masa por Ionización de ElectrosprayRESUMEN
This follow-up observational study examined gender disparities in seeking healthcare and in home management of diarrhoea, acute respiratory infections, and fever among 530 children (263 boys and 267 girls) aged less than five years in a rural community of West Bengal, India, from June 1998 to May 1999. Of 790 episodes detected by a weekly surveillance, 380 occurred among boys and 410 among girls. At the household level, girls were less likely to get home fluids and oral rehydration solutions (ORS) during diarrhoea. Qualified health professionals were consulted more often (p = 0.0094) and sooner for boys than for girls (8.3 +/- 4.5 hours vs 21.2 +/- 9.5 hours), for which parents also travelled longer distances (3.3 km for boys vs 1.6 km for girls). Expenditure per treated episode (Rs 76.76 +/- 69.23 in boys and Rs 44.73 +/- 67.60 in girls) differed significantly (p = 0.023). Results of logistic regression analysis showed that chance of spending more money was 4.2 [confidence interval (CI) 1.6-10.9] times higher for boys. The boys were 4.9 (CI 1.8-11.9) times more likely to be taken early for medical care and 2.6 (CI 1.2-6.5) times more likely to be seen by qualified allopathic doctors compared to girls. Persistence of gender disparities calls for effective interventions for correction.
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Servicios de Salud del Niño/estadística & datos numéricos , Madres/psicología , Aceptación de la Atención de Salud/etnología , Prejuicio , Servicios de Salud Rural/estadística & datos numéricos , Población Rural , Distribución por Sexo , Servicios de Salud del Niño/economía , Preescolar , Demografía , Diarrea/terapia , Composición Familiar , Femenino , Financiación Personal/estadística & datos numéricos , Estudios de Seguimiento , Humanos , India , Lactante , Recién Nacido , Masculino , Vigilancia de la Población , Factores SocioeconómicosRESUMEN
The glycosides methyl-2,6-dimethoxy-beta-D-galactopyranoside (beta-D-H(2)Me(3)GP), methyl-4,6-dimethoxy-alpha-D-mannopyranoside (alpha-D-H(2)Me(3)MP), and methyl-5-methoxy-beta-D-ribofuranoside (beta-D-H(2)Me(2)RF) have been synthesized, and their reaction with VO(L-Asal)(OMe)(OHMe) in dichloromethane has afforded esters of the type VO(beta-D-HMe(3)GP)(L-Asal), VO(alpha-D-HMe(3)MP)(L-Asal), and VO(beta-D-HMe(2)RF)(L-Asal) as dark-colored solids (red in solution). Here, L-Asal(2)(-) is the deprotonated salicylaldimine of L-alanine (A = a), L-valine (A = v), and L-phenylalanine (A = p). The X-ray structures of VO(beta-D-HMe(3)GP)(L-vsal).H(2)O and VO(alpha-D-HMe(3)MP)(L-psal).H(2)O have revealed five-membered (O,O)-chelation by monoionized carbohydrates, the undissociated hydroxyl group lying trans to the oxo oxygen atom. In the carbohydrate frame, the alkoxidic oxygen atom is axial in the former ester and equatorial in the latter. The V-O(alkoxidic) and V-O(alcoholic) distances are, respectively, approximately 1.80 and approximately 2.30 Å. The ONO coordinating tridentate salicylaldimine ligand is folded (by approximately 35 degrees ) along a C-N bond. The chiral configuration of the metal site corresponds exclusively to the endo disposition of the V=O and the amino acid C-R (R = Me, CHMe(2), CH(2)Ph) bonds. In VO(beta-D-HMe(3)GP)(L-vsal).H(2)O two ester molecules constitute the asymmetric unit and these along with the two water molecules form a macrocyclic supramolecule (diameter, approximately 6.1 Å) held by hydrogen bonds involving alcohol and an OMe function as well as water (O.O distance, 2.59-2.86 Å). On the other hand, in VO(alpha-D-HMe(3)MP)(L-psal).H(2)O the water molecule bridges two symmetry-related ester molecules via alkoxide.water and alcohol.water hydrogen bonds forming an infinite chain structure (O.O lengths, 2.65 and 2.85 Å). The molecular structures observed in the solid state are preserved in solution ((1)H and (51)V NMR). No isomerization is detectable either at the metal site or at the anomeric carbon atom, and the V-O(alkoxidic) and V-O(alcoholic) sites and the metal-carbohydrate binding remain in tact. The VO(beta-D-HMe(2)RF)(L-Asal) species did not afford single crystals but NMR results are consistent with (O,O)-chelation by the ribose fragment, the alkoxidic carbon being C3. Crystal data are as follows. VO(beta-D-HMe(3)GP)(L-vsal).H(2)O: chemical formula, C(21)H(32)NO(11)V; crystal system, orthorhombic; space group, P2(1)2(1)2(1); a = 13.146(7) Å, b = 15.142(5) Å, c = 25.631(9) Å; Z = 8. VO(alpha-D-HMe(3)MP)(L-psal).H(2)O: chemical formula, C(25)H(32)NO(11)V; crystal system, monoclinic; space group, P2(1); a = 13.645(4) Å, b = 7.022(2) Å, c = 15.500(4) Å; beta = 113.98(2) degrees; Z = 2.