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1.
J Chem Phys ; 160(21)2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38828812

RESUMEN

CNDOL is an a priori, approximate Fockian for molecular wave functions. In this study, we employ several modes of singly excited configuration interaction (CIS) to model molecular excitation properties by using four combinations of the one electron operator terms. Those options are compared to the experimental and theoretical data for a carefully selected set of molecules. The resulting excitons are represented by CIS wave functions that encompass all valence electrons in the system for each excited state energy. The Coulomb-exchange term associated to the calculated excitation energies is rationalized to evaluate theoretical exciton binding energies. This property is shown to be useful for discriminating the charge donation ability of molecular and supermolecular systems. Multielectronic 3D maps of exciton formal charges are showcased, demonstrating the applicability of these approximate wave functions for modeling properties of large molecules and clusters at nanoscales. This modeling proves useful in designing molecular photovoltaic devices. Our methodology holds potential applications in systematic evaluations of such systems and the development of fundamental artificial intelligence databases for predicting related properties.

2.
Clin Infect Dis ; 76(3): e544-e552, 2023 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-35666513

RESUMEN

BACKGROUND: Growing evidence indicates a causal relationship between SARS-CoV-2 infection and myocarditis. Post-authorization safety data have also identified myocarditis as a rare safety event following mRNA COVID-19 vaccination, particularly among adolescent and young-adult males after dose 2. We further evaluated the potential risk by querying the Moderna global safety database for myocarditis/myopericarditis reports among mRNA-1273 recipients worldwide. METHODS: Myocarditis/myopericarditis reports from 18 December 2020 to 15 February 2022 were reviewed and classified. The reported rate after any known mRNA-1273 dose was calculated according to age and sex, then compared with a population-based incidence rate to calculate observed-to-expected rate ratios (RRs). RESULTS: During the study period, 3017 myocarditis/myopericarditis cases among 252 million mRNA-1273 recipients who received at least 1 dose were reported to the Moderna global safety database. The overall reporting rate was 9.23 per 100 000 person-years, which was similar to the expected reference rate (9.0 cases per 100 000 person-years; RR [95% confidence interval (CI)], 1.03 [.97-1.08]). When stratified by sex and age, observed rates were highest for males aged <40 years, particularly those 18-24 years (53.76 per 100 000 person-years), which was higher than expected (RR [95% CI], 3.10 [2.68-3.58]). When considering only cases occurring within 7 days of a known dose, the observed rate was highest for males aged 18-24 years after dose 2 (4.23 per 100 000 doses administered). CONCLUSIONS: Myocarditis/myopericarditis rates were not higher than expected for the overall population of mRNA-1273 recipients but were higher than expected in males aged 18-24 years, with most cases occurring 7 days after dose 2.


Asunto(s)
COVID-19 , Miocarditis , Adolescente , Adulto , Masculino , Humanos , Vacuna nCoV-2019 mRNA-1273 , Vacunas contra la COVID-19 , Miocarditis/epidemiología , SARS-CoV-2 , Vacunación
3.
Chemphyschem ; 24(24): e202300485, 2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-37746771

RESUMEN

Weakly bound neon dimer, trimer and tetramers are studied at HF and CCSD(T) levels using Dunning, ANO and SIGMA-s basis sets. Their ground-state binding energies are studied along with some structural properties. SIGMA-s basis sets have been developed explicitly for this issue but in a manner that can be readily applied to other atoms for the study of larger weakly bound systems. The difficulties for attaining accurate results on these systems are assessed by the computation of total, atomization and correlation energies, as well as equilibrium distances, with several basis sets of increasing size, ranging from non-augmented to double-augmented versions. Extrapolations are proposed to predict stabilization energies and the results are compared with previously published data.

4.
Mar Drugs ; 19(2)2021 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-33578828

RESUMEN

Haloarchaea produce C50 carotenoids such as bacterioruberin, which are of biotechnological in-terest. This study aimed to analyze the effect of different environmental and nutritional conditions on the cellular growth and dynamics of carotenoids accumulation in Haloferax mediterranei. The maximum production of carotenoids (40 µg·mL-1) was obtained during the stationary phase of growth, probably due to nutrient-limiting conditions (one-step culture). By seven days of culture, 1 mL culture produced 22.4 mg of dry weight biomass containing 0.18 % (w/w) of carotenoids. On the other hand, carbon-deficient cultures (low C/N ratio) were observed to be optimum for C50 bacterioruberin production by Hfx. mediterranei, but negatively affected the growth of cells. Thus, a two-steps process was evaluated for optimum carotenoids yield. In the first step, a nutri-ent-repleted culture medium enabled the haloarchaea to produce biomass, while in the second step, the biomass was incubated under osmotic stress and in a carbon-deficient medium. Under the conditions used, the obtained biomass contained 0.27% (w/w) of carotenoids after seven days, which accounts for 58.49 µg·mL-1 of carotenoids for a culture with turbidity 14.0.


Asunto(s)
Biotecnología/métodos , Carotenoides/metabolismo , Haloferax mediterranei/metabolismo , Biomasa , Carbono/química , Medios de Cultivo , Factores de Tiempo
5.
Am J Physiol Cell Physiol ; 319(3): C552-C560, 2020 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-32697600

RESUMEN

A number of cell culture approaches have been described for maintenance of primary hepatocytes. Forming hepatocytes into three-dimensional (3-D) spheroids is one well-accepted method for extending epithelial phenotype of these cells. Our laboratory has previously observed enhanced function of two-dimensional (2-D, monolayer) hepatocyte cultures in microfluidic devices due to increased production of several hepato-inductive growth factors, including hepatocyte growth factor (HGF). In the present study, we wanted to test a hypothesis that culturing hepatocyte spheroids (3-D) in microfluidic devices will also result in enhanced phenotype and function. To test this hypothesis, we fabricated devices with small and large volumes. Both types of devices included a microstructured floor containing arrays of pyramidal wells to promote assembly of hepatocytes into spheroids with individual diameters of ~100 µm. The hepatocyte spheroids were found to be more functional, as evidenced by higher level of albumin synthesis, bile acid production, and hepatic enzyme expression, in low-volume compared with large-volume devices. Importantly, high functionality of spheroid cultures correlated with elevated levels of HGF secretion. Although decay of hepatic function (albumin secretion) was observed over the course 3 wk, this behavior could be abrogated by inhibiting TGF-ß1 signaling. With TGF-ß1 inhibitor, microfluidic hepatocyte spheroid cultures maintained high and stable levels of albumin synthesis over the course of 4 wk. To further highlight utility of this culture platform for liver disease modeling, we carried out alcohol injury experiments in microfluidic devices and tested protective effects of interleukin-22: a potential therapy for alcoholic hepatitis.


Asunto(s)
Hepatocitos/metabolismo , Microfluídica , Animales , Supervivencia Celular , Células Cultivadas , Técnicas de Cocultivo/métodos , Microfluídica/métodos , Fenotipo , Esferoides Celulares/metabolismo
6.
J Phys Chem A ; 124(1): 126-134, 2020 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-31815472

RESUMEN

Following a previous work, we have assessed the feasibility of MP2/CBS(d, t) as an alternative to state-of-the-art density functionals. The effect of using augmented basis sets is here tested on the 76 barrier heights and 10 isomerization reactions previously utilized. Moreover, calculations for 20 sets of the GMTKN24 database for thermochemistry, kinetics, and noncovalent interactions have been performed. For the density functional theory calculations, M06-2X and B3LYP-D3 functionals are utilized as two representative functionals, while MP2 and CCSD(T) methods are employed as the ab initio counterparts. The results show that MP2 calculations perform similarly to the ones obtained with M06-2X insofar as accuracy and computational cost are concerned. For all methods, the use of augmented basis sets yields enhanced results for anionic systems when compared with the ones from non-augmented bases. Otherwise, the basis-set change effect is found to be minimal. It is therefore concluded that the use of large basis sets is unjustified when facing the increase in computational cost.

7.
Contact Dermatitis ; 83(6): 466-474, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32592184

RESUMEN

BACKGROUND: Occupational contact urticaria due to inhalation of legume pest allergens has rarely been described. OBJECTIVE: To determine the cause of an outbreak of airborne contact urticaria, asthma, and anaphylaxis in farmers and agronomists studying the disinsectization of dried peas. Peas were treated with aluminum phosphide (EPA). METHODS: Extracts prepared from Bruchus lentis and Bruchus pisorum bodies and from healthy legumes, EPA-treated legumes, and infested legumes, were used for in vivo tests (skin prick testing, oral, and specific bronchial challenge for the diagnosis of asthma and anaphylaxis) in affected patients and in five control patients with severe legume hypersensitivity. Open application, patch testing with the most common legume insecticides, molecular analysis, and IgE immunoblotting were undertaken. RESULTS: We found positive responses (prick, provocation, immune detection) to parasitic pea extracts and B. pisorum. A 25 kDa band was detected in the western blot of all patients who worked with infested EPA-treated peas. Bands from B. pisorum extract were detected in all patients. No responses to pea allergens were found in any patient, unlike in legume allergy controls. Oral provocation tests were negative. CONCLUSION: B. pisorum is a cause of contact urticaria and may cause occupational hives, anaphylaxis, and asthma. The allergen may enter by inhalation or puncture of setae released by B. pisorum.


Asunto(s)
Anafilaxia/etiología , Asma/diagnóstico , Dermatitis Alérgica por Contacto/diagnóstico , Fabaceae/efectos adversos , Agricultores/estadística & datos numéricos , Adulto , Anafilaxia/diagnóstico , Asma/inducido químicamente , Dermatitis Alérgica por Contacto/etiología , Femenino , Hipersensibilidad a los Alimentos/etiología , Humanos , Inmunoglobulina E/inmunología , Masculino , Persona de Mediana Edad , Pruebas Cutáneas
8.
Sensors (Basel) ; 20(9)2020 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-32365631

RESUMEN

The topological derivative tool is applied here in structural health monitoring (SHM) problems to locate small defects in a material plate with complex geometry that is subject to permanent multifrequency guided waves excitation. Compared to more standard SHM methods, based in measuring the time-lag between emitted and received propagative pulses plus some postprocessing, the topological derivative somehow compares the measured and computed (solving the full elasto-dynamic equations) response of the damaged plate, instead of relying on only the time of flight of the wave. Thus, the method profits the knowledge behind the physics of the problem and can cope with scenarios in which classical methods give poor results. The authors of this paper have already used the topological derivative in rectangular plates with constant thickness, but with defects consisting simply in both through slits and inclusions of a different material, and actuators/sensors located near the boundary, which makes very difficult to use standard SHM methods. This is an extension of the method, also considering the much more difficult to analyze case of plates with variable thickness and complex (non-rectangular) planform.

9.
BMC Genomics ; 18(1): 781, 2017 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-29025409

RESUMEN

BACKGROUND: Asparagine is a very important nitrogen transport and storage compound in plants due to its high nitrogen/carbon ratio and stability. Asparagine intracellular concentration depends on a balance between asparagine biosynthesis and degradation. The main enzymes involved in asparagine metabolism are asparagine synthetase (ASN), asparaginase (NSE) and serine-glyoxylate aminotransferase (SGAT). The study of the genes encoding for these enzymes in the model legume Lotus japonicus is of particular interest since it has been proposed that asparagine is the principal molecule used to transport reduced nitrogen within the plant in most temperate legumes. RESULTS: A differential expression of genes encoding for several enzymes involved in asparagine metabolism was detected in L. japonicus. ASN is encoded by three genes, LjASN1 was the most highly expressed in mature leaves while LjASN2 expression was negligible and LjASN3 showed a low expression in this organ, suggesting that LjASN1 is the main gene responsible for asparagine synthesis in mature leaves. In young leaves, LjASN3 was the only ASN gene expressed although at low levels, while all the three genes encoding for NSE were highly expressed, especially LjNSE1. In nodules, LjASN2 and LjNSE2 were the most highly expressed genes, suggesting an important role for these genes in this organ. Several lines of evidence support the connection between asparagine metabolic genes and photorespiration in L. japonicus: a) a mutant plant deficient in LjNSE1 showed a dramatic decrease in the expression of the two genes encoding for SGAT; b) expression of the genes involved in asparagine metabolism is altered in a photorespiratory mutant lacking plastidic glutamine synthetase; c) a clustering analysis indicated a similar pattern of expression among several genes involved in photorespiratory and asparagine metabolism, indicating a clear link between LjASN1 and LjSGAT genes and photorespiration. CONCLUSIONS: The results obtained in this paper indicate the existence of a differential expression of asparagine metabolic genes in L. japonicus and point out the crucial relevance of particular genes in different organs. Moreover, the data presented establish clear links between asparagine and photorespiratory metabolic genes in this plant.


Asunto(s)
Asparagina/metabolismo , Respiración de la Célula/efectos de la radiación , Perfilación de la Expresión Génica , Luz , Lotus/genética , Lotus/metabolismo , Respiración de la Célula/genética , Lotus/efectos de la radiación , Mutación , ARN Mensajero/genética , ARN Mensajero/metabolismo , Transcripción Genética/efectos de la radiación
10.
Oncologist ; 22(10): 1160-1168, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28592618

RESUMEN

BACKGROUND: VELVET Cohort 1 demonstrated the applicability of pertuzumab, trastuzumab, and vinorelbine as an alternative first-line treatment regimen for patients with HER2-positive locally advanced or metastatic breast cancer (MBC) who cannot receive docetaxel. Co-infusion of pertuzumab and trastuzumab may reduce clinic time and medical resource utilization. We report results from Cohort 2, in which pertuzumab and trastuzumab were co-infused, followed by vinorelbine. PATIENTS AND METHODS: During cycle 1, patients with HER2-positive locally advanced or MBC received loading doses of pertuzumab (840 mg) and trastuzumab (8 mg/kg) on consecutive days, followed by vinorelbine (25 mg/m2) on days two and nine. From cycle 2 onwards, patients received a co-infusion of pertuzumab (420 mg) and trastuzumab (6 mg/kg) on day one, followed by vinorelbine (30-35 mg/m2) on days one and eight (or days two and nine). The primary endpoint was objective response rate (ORR) in patients with measurable disease. Secondary endpoints included progression-free survival (PFS) and safety. RESULTS: Cohort 2 enrolled 107 patients. The ORR was 63.7% (95% confidence interval [CI] 53.0-73.6) in patients with measurable disease (91/107; 85.0%). Median PFS was 11.5 months (95% CI 10.3-15.8). The most common adverse events [AEs] were diarrhea (57.9%), neutropenia (57.0%), and nausea (41.1%). Grade ≥3 AEs occurred in 85 patients (79.4%) and serious AEs in 44 patients (41.1%). Eighteen patients (16.8%) had AEs suggestive of congestive heart failure. CONCLUSION: These results support the feasibility of pertuzumab and trastuzumab co-infusion from a safety perspective and support Cohort 1 conclusions that vinorelbine offers an alternative chemotherapy companion for pertuzumab and trastuzumab. The Oncologist 2017;22:1160-1168 IMPLICATIONS FOR PRACTICE: Combined treatment with pertuzumab, trastuzumab, and docetaxel is the standard of care for first-line HER2-positive metastatic breast cancer. However, some patients cannot, or choose not to, receive docetaxel. VELVET Cohort 2 results support the results from Cohort 1 that suggest that pertuzumab plus trastuzumab and vinorelbine is a suitable alternative for these patients. In addition to this, results from Cohort 2 support the feasibility of administering pertuzumab and trastuzumab together in a single infusion bag, which has the potential to offer greater patient convenience and reduce active health care professional time and medical resource utilization compared with administering them separately.


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Trastuzumab/uso terapéutico , Vinblastina/análogos & derivados , Anticuerpos Monoclonales Humanizados/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Neoplasias de la Mama/patología , Femenino , Humanos , Trastuzumab/farmacología , Resultado del Tratamiento , Vinblastina/farmacología , Vinblastina/uso terapéutico , Vinorelbina
11.
Chemistry ; 23(38): 9122-9129, 2017 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-28380281

RESUMEN

To assess the title issue, 38 hydrogen transfer barrier heights and 38 non-hydrogen transfer barrier heights/isomerizations extracted from extensive databases have been considered, in addition to 4 2 p-isomerization reactions and 6 others for large organic molecules. All Kohn-Sham DFT calculations have employed the popular M06-2X functional, whereas the correlated molecular orbital (MO)-based ones are from single-reference MP2 and CCSD(T) methods. They have all utilized the same basis sets, with raw MO energies subsequently extrapolated to the complete basis set limit without additional cost. MP2 calculations are found to be as cost-effective as DFT ones and often slightly more, while showing a satisfactory accuracy when compared with the reference data. Although the focus is on barrier heights, the results may bear broader implications, in that one may see successes and difficulties of DFT when compared with traditional MO theories for the same data.

12.
Pediatr Transplant ; 21(7)2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28608489

RESUMEN

Aim was to determine whether CGM could accurately monitor blood glucose concentration in the immediate postoperative period following pancreatectomy with IAT in children. CGM was used in nine patients undergoing IAT at our institution between April 2015 and September 2016 (eight total pancreatectomy and one subtotal pancreatectomy). MAD and MARD of CGM values compared to time-matched serum blood glucose were calculated during the first 5 days of ICU admission. Goal range was defined as 70-140 mg/dL and out-of-range was >140 mg/dL or <70 mg/dL. Of 89 time-matched measures found, 75% of CGM values were within 15 mg/dL, and 51% were within 10 mg/dL, compared to serum glucose. MAD was 11.6 mg/dL, and MARD was 10.6%. CGM values did not differ from serum glucose (P=.74). By Clarke error grid analysis, 100% of paired values were in clinically acceptable zones. By surveillance error grid analysis, 96% of paired values were within clinically acceptable agreement. CGM is a reliable tool in monitoring glycemic control in the immediate postoperative period following pancreatectomy with IAT in children.


Asunto(s)
Glucemia/análisis , Hiperglucemia/diagnóstico , Hipoglucemia/diagnóstico , Trasplante de Islotes Pancreáticos , Pancreatectomía , Cuidados Posoperatorios/métodos , Complicaciones Posoperatorias/diagnóstico , Adolescente , Biomarcadores/análisis , Glucemia/metabolismo , Niño , Femenino , Humanos , Hiperglucemia/sangre , Hiperglucemia/etiología , Hipoglucemia/sangre , Hipoglucemia/etiología , Trasplante de Islotes Pancreáticos/métodos , Masculino , Monitoreo Fisiológico , Complicaciones Posoperatorias/sangre , Estudios Retrospectivos , Trasplante Autólogo
13.
Antimicrob Agents Chemother ; 60(8): 5076-9, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27270288

RESUMEN

LpxC inhibitors have generally shown poor in vitro activity against Acinetobacter baumannii We show that the LpxC inhibitor PF-5081090 inhibits lipid A biosynthesis, as determined by silver staining and measurements of endotoxin levels, and significantly increases cell permeability. The presence of PF-5081090 at 32 mg/liter increased susceptibility to rifampin, vancomycin, azithromycin, imipenem, and amikacin but had no effect on susceptibility to ciprofloxacin and tigecycline. Potentiating existing antibiotics with LpxC inhibitors may represent an alternative treatment strategy for multidrug-resistant A. baumannii.


Asunto(s)
Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/metabolismo , Antibacterianos/farmacología , Carbapenémicos/farmacología , Infecciones por Acinetobacter/microbiología , Amidohidrolasas/antagonistas & inhibidores , Amidohidrolasas/metabolismo , Amicacina/farmacología , Azitromicina/farmacología , Proteínas Bacterianas/antagonistas & inhibidores , Proteínas Bacterianas/metabolismo , Farmacorresistencia Bacteriana Múltiple , Imipenem/farmacología , Pruebas de Sensibilidad Microbiana , Minociclina/análogos & derivados , Minociclina/farmacología , Rifampin/farmacología , Tigeciclina , Vancomicina/farmacología
14.
Phys Chem Chem Phys ; 18(3): 2175-82, 2016 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-26690957

RESUMEN

The modern computer simulations of potential green solvents of the future, involving the room temperature ionic liquids, heavily rely on density functional theory (DFT). In order to verify the appropriateness of the common DFT methods, we have investigated the effect of the self-interaction error (SIE) on the results of DFT calculations for 24 ionic pairs and 48 ionic associates. The magnitude of the SIE is up to 40 kJ mol(-1) depending on the anion choice. Most strongly the SIE influences the calculation results of ionic associates that contain halide anions. For these associates, the range-separated density functionals suppress the SIE; for other cases, the revPBE density functional with dispersion correction and triple-ζ Slater-type basis is suitable for computationally inexpensive and reasonably accurate DFT calculations.

15.
J Phys Chem A ; 120(44): 8830-8842, 2016 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-27762553

RESUMEN

The retro-cycloaddition thermal reaction of isoxazolino[4,5:1,2][60]fullerenes to pristine fullerene seems to be guided by the electronic nature of the substituted nitrile oxide 1,3-dipole in the isoxazoline ring. Trapping experiments proved that the reaction mechanism occurs by thermal removal of the nitrile oxide 1,3-dipole in a process that is favored in the presence of a big excess of a highly efficient dipolarophile such as maleic anhydride. Theoretical gas phase calculations carried out at the B3LYP/6-31G(d) and M06-2X/6-31G(d) levels of theory underpin the experimental findings and predict that compound 1c, bearing the p-(CH3)2N-Ph substituent on the isoxazoline ring and with a remarkable experimental conversion efficiency in just 12 h, showed the lowest activation energy. Solvent calculations have predicted the same behavior in gas phase. Different approaches such as electrostatic natural population analysis and Houk's distortion/interaction model have been applied to understand how the electronic nature of these substituents affects the retro-cycloaddition reaction process. Analysis of the values of the condensed Fukui functions and dual descriptor shed light on the mechanism of the retro-cycloaddition reaction.

16.
Mol Divers ; 20(2): 421-38, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26553204

RESUMEN

A novel heuristic using an iterative select-and-purge strategy is proposed. It combines statistical techniques for sampling and classification by rigid molecular docking through an inverse virtual screening scheme. This approach aims to the de novo discovery of short peptides that may act as docking receptors for small target molecules when there are no data available about known association complexes between them. The algorithm performs an unbiased stochastic exploration of the sample space, acting as a binary classifier when analyzing the entire peptides population. It uses a novel and effective criterion for weighting the likelihood of a given peptide to form an association complex with a particular ligand molecule based on amino acid sequences. The exploratory analysis relies on chemical information of peptides composition, sequence patterns, and association free energies (docking scores) in order to converge to those peptides forming the association complexes with higher affinities. Statistical estimations support these results providing an association probability by improving predictions accuracy even in cases where only a fraction of all possible combinations are sampled. False positives/false negatives ratio was also improved with this method. A simple rigid-body docking approach together with the proper information about amino acid sequences was used. The methodology was applied in a retrospective docking study to all 8000 possible tripeptide combinations using the 20 natural amino acids, screened against a training set of 77 different ligands with diverse functional groups. Afterward, all tripeptides were screened against a test set of 82 ligands, also containing different functional groups. Results show that our integrated methodology is capable of finding a representative group of the top-scoring tripeptides. The associated probability of identifying the best receptor or a group of the top-ranked receptors is more than double and about 10 times higher, respectively, when compared to classical random sampling methods.


Asunto(s)
Biología Computacional/métodos , Evaluación Preclínica de Medicamentos/métodos , Péptidos/metabolismo , Receptores Artificiales/metabolismo , Bibliotecas de Moléculas Pequeñas/metabolismo , Bibliotecas de Moléculas Pequeñas/farmacología , Algoritmos , Ligandos , Simulación del Acoplamiento Molecular , Curva ROC , Procesos Estocásticos , Termodinámica , Interfaz Usuario-Computador
17.
Ann Surg ; 260(1): 56-64, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24509206

RESUMEN

OBJECTIVE: Describe the surgical technique, complications, and long-term outcomes of total pancreatectomy and islet autotransplantation (TP-IAT) in a large series of pediatric patients. BACKGROUND: Surgical management of childhood pancreatitis is not clear; partial resection or drainage procedures often provide transient pain relief, but long-term recurrence is common due to the diffuse involvement of the pancreas. Total pancreatectomy (TP) removes the source of the pain, whereas islet autotransplantation (IAT) potentially can prevent or minimize TP-related diabetes. METHODS: Retrospective review of 75 children undergoing TP-IAT for chronic pancreatitis who had failed medical, endoscopic, or surgical treatment between 1989 and 2012. RESULTS: Pancreatitis pain and the severity of pain statistically improved in 90% of patients after TP-IAT (P < 0.001). The relief from narcotics was sustained. Of the 75 patients undergoing TP-IAT, 31 (41.3%) achieved insulin independence. Younger age (P = 0.032), lack of prior Puestow procedure (P = 0.018), lower body surface area (P = 0.048), higher islet equivalents (IEQ) per kilogram body weight (P = 0.001), and total IEQ (100,000) (P = 0.004) were associated with insulin independence. By multivariate analysis, 3 factors were associated with insulin independence after TP-IAT: (1) male sex, (2) lower body surface area, and (3) higher total IEQ per kilogram body weight. Total IEQ (100,000) was the single factor most strongly associated with insulin independence (odds ratio = 2.62; P < 0.001). CONCLUSIONS: Total pancreatectomy and islet autotransplantation provides sustained pain relief and improved quality of life. The ß-cell function is dependent on islet yield. Total pancreatectomy and islet autotransplantation is an effective therapy for children with painful pancreatitis that failed medical and/or endoscopic management.


Asunto(s)
Dolor Abdominal/terapia , Trasplante de Islotes Pancreáticos/métodos , Pancreatectomía/métodos , Pancreatitis Crónica/cirugía , Cuidados Posoperatorios/métodos , Dolor Abdominal/diagnóstico , Dolor Abdominal/etiología , Adolescente , Niño , Colangiopancreatografia Retrógrada Endoscópica , Endosonografía , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Minnesota/epidemiología , Dimensión del Dolor , Pancreatitis Crónica/complicaciones , Pancreatitis Crónica/diagnóstico , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/prevención & control , Calidad de Vida , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Factores de Tiempo , Tomografía Computarizada por Rayos X , Trasplante Autólogo , Resultado del Tratamiento
18.
J Exp Bot ; 65(19): 5557-66, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24948681

RESUMEN

This review summarizes the most recent results obtained in the analysis of two important metabolic pathways involved in the release of internal sources of ammonium in the model legume Lotus japonicus: photorespiratory metabolism and asparagine breakdown mediated by aparaginase (NSE). The use of photorespiratory mutants deficient in plastidic glutamine synthetase (GS2) enabled us to investigate the transcriptomics and metabolomic changes associated with photorespiratory ammonium accumulation in this plant. The results obtained indicate the existence of a coordinate regulation of genes involved in photorespiratory metabolism. Other types of evidence illustrate the multiple interconnections existing among the photorespiratory pathway and other processes such as intermediate metabolism, nodule function, and secondary metabolism in this plant, all of which are substantially affected in GS2-deficient mutants because of the impairment of the photorespiratory cycle. Finally, the importance of asparagine metabolism in L. japonicus is highlighted because of the fact that asparagine constitutes the vast majority of the reduced nitrogen translocated between different organs of this plant. The different types of NSE enzymes and genes which are present in L. japonicus are described. There is a particular focus on the most abundant K(+)-dependent LjNSE1 isoform and how TILLING mutants were used to demonstrate by reverse genetics the importance of this particular isoform in plant growth and seed production.


Asunto(s)
Compuestos de Amonio/metabolismo , Asparagina/metabolismo , Regulación de la Expresión Génica de las Plantas , Glutamato-Amoníaco Ligasa/metabolismo , Lotus/metabolismo , Nitrógeno/metabolismo , Transporte Biológico , Respiración de la Célula , Glutamato-Amoníaco Ligasa/genética , Luz , Lotus/genética , Lotus/efectos de la radiación , Estructura Molecular , Mutación , Plastidios/enzimología , Potasio/metabolismo , Genética Inversa , Semillas/genética , Semillas/metabolismo , Semillas/efectos de la radiación , Transcriptoma
19.
Alcohol Clin Exp Res ; 38(9): 2502-8, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25159809

RESUMEN

BACKGROUND: Because prenatal alcohol exposure is associated with growth deficiency, little attention has been paid to the potential for overweight and obesity in children with fetal alcohol spectrum disorders (FASD). This study examined the prevalence of overweight/obesity (body mass index [BMI]) in a large clinical sample of children with FASD. METHODS: Children, aged 2 to 19 years, who were evaluated for FASD at University Clinics, included 445 with an FASD diagnosis and 171 with No-FASD diagnosis. Prevalence of overweight/obesity (BMI ≥ 85 percentile) was compared to national and state prevalence. BMI was examined in relation to FASD diagnosis, gender, and age. Dietary intake data were examined for a young subsample (n = 42). RESULTS: Thirty-four percent with any FASD diagnosis were overweight or obese, which did not differ from the No-FASD group or U.S. prevalence. Underweight was prevalent in those with fetal alcohol syndrome (FAS) (17%). However, increased rates of overweight/obesity were seen in those with partial FAS (40%). Among adolescents, those with any FASD diagnosis had increased overweight/obesity (42%), particularly among females (50%). The rate in adolescent females with FASD (50%) was nearly 3 times higher than state prevalence for adolescent females (17 to 18%), p < 0.001. In the young subsample, those who were overweight/obese consumed more calories, protein, and total fat per day than those who were not overweight or obese. CONCLUSIONS: Rates of overweight/obesity are increased in children with partial FAS. In adolescents, rates are increased for any FASD diagnosis (particularly in females). Results are suggestive of possible metabolic/endocrine disruption in FASD-a hypothesis for which there is evidence from animal models. These data suggest that clinicians may consider prenatal alcohol exposure as a risk factor for metabolic/endocrine disruption, should evaluate diet as a risk in this population, and may need to target interventions to females prior to puberty to effect changes in overweight-related outcomes.


Asunto(s)
Índice de Masa Corporal , Trastornos del Espectro Alcohólico Fetal/diagnóstico , Trastornos del Espectro Alcohólico Fetal/epidemiología , Obesidad/diagnóstico , Obesidad/epidemiología , Adolescente , Consumo de Bebidas Alcohólicas/efectos adversos , Consumo de Bebidas Alcohólicas/epidemiología , Niño , Preescolar , Femenino , Humanos , Masculino , Sobrepeso/diagnóstico , Sobrepeso/epidemiología , Embarazo , Factores de Riesgo , Adulto Joven
20.
J Org Chem ; 79(8): 3473-86, 2014 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-24665860

RESUMEN

New [60]fullerene-steroid conjugates (4-6) have been synthesized by 1,3-dipolar cycloaddition and Bingel-Hirsch cyclopropanation reactions from suitably functionalized epiandrosterone and [60]fullerene. Since a new stereocenter is created in the formation of the Prato monoaduct, two different diastereomers were isolated by HPLC (4, 5) whose absolute configurations were assigned according to the highly reliable "sector rule" on fullerenes. A further reaction of the malonate-containing diastereomer 5 with a second C60 molecule has afforded dumbbell fullerene 6 in which the two fullerene units are covalently connected through an epiandrosterone moiety. The new compounds have been spectroscopically characterized and their redox potentials, determined by cyclic voltametry, reveal three reversible reduction waves for hybrids 4 and 5, whereas these signals are split in dumbbell 6. Theoretical calculations at semiempirical (AM1) and single point B3LYP/6-31G(d) levels have predicted the most stable conformations for the hybrid compounds (4-6), showing the importance of the chlorine atom on the D ring of the steroid. Furthermore, TDDFT calculations have allowed assignments of the experimentally determined circular dichroism (CD) of the [60]fullerene-steroid hybrids based on the sign and position of the Cotton effects, despite the exceptionally large systems under study.


Asunto(s)
Fulerenos/química , Esteroides/química , Cromatografía Líquida de Alta Presión , Dicroismo Circular , Espectroscopía de Resonancia Magnética , Modelos Teóricos , Conformación Molecular , Estereoisomerismo
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