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1.
Environ Res ; 241: 117622, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-37977273

RESUMEN

BACKGROUND: Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCB), they have contributed to the exposure of women to persistent organic pollutants (POPs). These compounds can cross the placental barrier and interfere with the hormonal system of newborns. AIM: To determine concentrations of OCPs and PCBs and their xenoestrogenic activity in placentas of women from the PA-MAMI cohort of Panama. METHODS: Thirty-nine placenta samples from women in the Azuero peninsula (Panama) were analyzed. Five OCPs [p-p'-dichlorodiphenyldichloroethylene (p-p'-DDE), beta-hexachlorohexane (ß-HCH), γ-hexachlorohexane (lindane), hexachlorobenzene (HCB) and mirex] and three PCB congeners (PCB-138, PCB-153 and PCB-180) were quantified in placenta extracts. The xenoestrogenic activity of extracts was assessed with the E-Screen bioassay to estimate the total effective xenoestrogen burden (TEXB). RESULTS: All placental samples were positive for at least three POP residues and >70% for at least six. The frequencies of quantified OCPs ranged from 100% for p,p'-DDE and HCB to 30.8% for ß-HCH. The highest median concentration was for lindane (380.0 pg/g placenta), followed by p,p'-DDE (280.0 pg/g placenta), and HCB (90.0 pg/g placenta). Exposure to p,p'-DDE was associated with greater meat consumption, suggesting that animal fat is a major source of exposure to DDT metabolites. The frequency of detected PCBs ranged between 70 and 90%; the highest median concentration was for PCB 138 (17.0 pg/g placenta), followed by PCB 153 (16.0 pg/g placenta). All placentas were positive in the estrogenicity bioassay with a median TEXB-α of 0.91 pM Eeq/g of placenta. Exposure to lindane was positively associated with the xenoestrogenicity of TEXB- α, whereas this association was negative in the case of exposure to PCB 153. CONCLUSIONS: To our best knowledge, this study contributes the first evidence on the presence of POPs and xenoestrogenic burden in placentas from Latin-American women. Given concerns about the consequences of prenatal exposure to these compounds on children's health, preventive measures are highly recommended to eliminate or minimize the risk of OCP exposure during pregnancy.


Asunto(s)
Contaminantes Ambientales , Hidrocarburos Clorados , Plaguicidas , Bifenilos Policlorados , Recién Nacido , Animales , Femenino , Humanos , Embarazo , Bifenilos Policlorados/análisis , Hexaclorociclohexano/análisis , Hexaclorociclohexano/metabolismo , Diclorodifenil Dicloroetileno , Hexaclorobenceno/análisis , DDT/análisis , Placenta/química , Hidrocarburos Clorados/análisis , Plaguicidas/análisis , Contaminantes Ambientales/análisis , Relaciones Madre-Hijo
2.
J Endocrinol Invest ; 47(6): 1405-1418, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38218741

RESUMEN

OBJECTIVES: To examine the cross-sectional association between baseline depressive symptoms and the presence of type 2 diabetes (T2D), and its association with glycated hemoglobin (HbA1c) and other metabolic variables, and the prospective association of depressive symptoms and HbA1c after 1 year of follow-up. METHODS: n = 6224 Mediterranean older adults with overweight/obesity and metabolic syndrome (48% females, mean age 64.9 ± 4.9 years) were evaluated in the framework of the PREDIMED-Plus study cohort. Depressive symptoms were assessed using the Beck Depression Inventory-II and HbA1c was used to measure metabolic control. RESULTS: The presence of T2D increased the likelihood of higher levels of depressive symptoms (χ2 = 15.84, p = 0.001). Polynomial contrast revealed a positive linear relationship (χ2 = 13.49, p = 0.001), the higher the depressive symptoms levels, the higher the prevalence of T2D. Longitudinal analyses showed that the higher baseline depressive symptoms levels, the higher the likelihood of being within the HbA1c ≥ 7% at 1-year level (Wald-χ2 = 24.06, df = 3, p < .001, for the full adjusted model). Additionally, depressive levels at baseline and duration of T2D predicted higher HbA1c and body mass index, and lower physical activity and adherence to Mediterranean Diet at 1 year of follow-up. CONCLUSIONS: This study supports an association between T2D and the severity of depressive symptoms, suggesting a worse metabolic control from mild severity levels in the short-medium term, influenced by lifestyle habits related to diabetes care. Screening for depressive symptoms and a multidisciplinary integrative therapeutic approach should be ensured in patients with T2D.


Asunto(s)
Depresión , Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/psicología , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/complicaciones , Femenino , Masculino , Persona de Mediana Edad , Estudios de Seguimiento , Depresión/epidemiología , Depresión/etiología , Anciano , Estudios Transversales , Hemoglobina Glucada/análisis , Estudios Prospectivos , Dieta Mediterránea , Prevalencia , Índice de Masa Corporal , Obesidad/psicología , Obesidad/epidemiología , Obesidad/complicaciones , Síndrome Metabólico/epidemiología , Síndrome Metabólico/psicología
3.
Dev Genes Evol ; 233(2): 91-106, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37410100

RESUMEN

The African bichir (Polypterus senegalus) is a living representative of Polypteriformes. P. senegalus possesses teeth composed of dentin covered by an enameloid cap and a layer of collar enamel on the tooth shaft, as in lepisosteids. A thin layer of enamel matrix can also be found covering the cap enameloid after its maturation and during the collar enamel formation. Teleosts fish do not possess enamel; teeth are protected by cap and collar enameloid, and inversely in sarcopterygians, where teeth are only covered by enamel, with the exception of the cap enameloid in teeth of larval urodeles. The presence of enameloid and enamel in the teeth of the same organism is an opportunity to solve the evolutionary history of the presence of enamel/enameloid in basal actinopterygians. In silico analyses of the jaw transcriptome of a juvenile bichir provided twenty SCPP transcripts. They included enamel, dentin, and bone-specific SCPPs known in sarcopterygians and several actinopterygian-specific SCPPs. The expression of these 20 genes was investigated by in situ hybridizations on jaw sections during tooth and dentary bone formation. A spatiotemporal expression patterns were established and compared with previous studies of SCPP gene expression during enamel/enameloid and bone formation. Similarities and differences were highlighted, and several SCPP transcripts were found specifically expressed during tooth or bone formation suggesting either conserved or new functions of these SCPPs.


Asunto(s)
Calcificación Fisiológica , Diente , Animales , Calcificación Fisiológica/genética , Senegal , Diente/metabolismo , Peces/genética , Evolución Biológica
4.
Ann Oncol ; 34(1): 78-90, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36220461

RESUMEN

BACKGROUND: The standard treatment of T2-T3ab,N0,M0 rectal cancers is total mesorectal excision (TME) due to the high recurrence rates recorded with local excision. Initial reports of the combination of pre-operative chemoradiotherapy (CRT) and transanal endoscopic microsurgery (TEM) have shown reductions in local recurrence. The TAU-TEM study aims to demonstrate the non-inferiority of local recurrence and the improvement in morbidity achieved with CRT-TEM compared with TME. Here we describe morbidity rates and pathological outcomes. PATIENTS AND METHODS: This was a prospective, multicentre, randomised controlled non-inferiority trial including patients with rectal adenocarcinoma staged as T2-T3ab,N0,M0. Patients were randomised to the CRT-TEM or the TME group. Patients included, tolerance of CRT and its adverse effects, surgical complications (Clavien-Dindo and Comprehensive Complication Index classifications) and pathological results (complete response in the CRT-TEM group) were recorded in both groups. Patients attended follow-up controls for local and systemic relapse. TRIAL REGISTRATION: NCT01308190. RESULTS: From July 2010 to October 2021, 173 patients from 17 Spanish hospitals were included (CRT-TEM: 86, TME: 87). Eleven were excluded after randomisation (CRT-TEM: 5, TME: 6). Modified intention-to-treat analysis thus included 81 patients in each group. There was no mortality after CRT. In the CRT-TEM group, one patient abandoned CRT, 1/81 (1.2%). The CRT-related morbidity rate was 29.6% (24/81). Post-operative morbidity was 17/82 (20.7%) in the CRT-TEM group and 41/81 (50.6%) in the TME group (P < 0.001, 95% confidence interval 42.9% to 16.7%). One patient died in each group (1.2%). Of the 81 patients in the CRT-TEM group who received the allocated treatment, 67 (82.7%) underwent organ preservation. Pathological complete response in the CRT-TEM group was 44.3% (35/79). In the TME group, pN1 were found in 17/81 (21%). CONCLUSION: CRT-TEM treatment obtains high pathological complete response rates (44.3%) and a high CRT compliance rate (98.8%). Post-operative complications and hospitalisation rates were significantly lower than those in the TME group. We await the results of the follow-up regarding cancer outcomes and quality of life.


Asunto(s)
Neoplasias del Recto , Microcirugía Endoscópica Transanal , Humanos , Microcirugía Endoscópica Transanal/métodos , Resultado del Tratamiento , Estudios Prospectivos , Calidad de Vida , Recurrencia Local de Neoplasia/patología , Neoplasias del Recto/tratamiento farmacológico , Neoplasias del Recto/radioterapia , Neoplasias del Recto/cirugía , Quimioradioterapia , Terapia Neoadyuvante/efectos adversos , Terapia Neoadyuvante/métodos , Estadificación de Neoplasias
5.
Arch Virol ; 166(2): 535-544, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33403475

RESUMEN

In vitro cell cultures are widely used models for dissecting cellular and molecular mechanisms that lead to certain physiological conditions and diseases. The pathogenesis of BoHV-4 in the bovine reproductive tract has been studied by conducting tests on primary cultures. However, many questions remain to be answered about the role of BoHV-4 in endometrial cells. The aim of this study was to compare the replication and gene expression of BoHV-4 in cell lines and bovine reproductive tract primary cells as an in vitro model for the study of this virus. We demonstrated that BoHV-4 strains differ in their in vitro growth kinetics and gene expression but have the same cell type preference. Our results demonstrate that BoHV-4 replicates preferentially in bovine endometrial cells (BEC). However, its replication capacity extends to various cell types, since all cells that were tested were permissive to BoHV-4 infection. The highest virus titers were obtained in BEC cells. Nevertheless, virus replication efficiency could not be fully predicted from the mRNA expression profiles. This implies that there are multiple cell-type-dependent factors and strain properties that determine the level of BoHV-4 replication. The results of this study provide relevant information about the in vitro behavior of two field isolates of BoHV-4 in different cell cultures. These findings may be useful for the design of future in vitro experiments to obtain reliable results not only about the pathogenic role of BoHV-4 in the bovine female reproductive tract but also in the development of efficient antiviral strategies.


Asunto(s)
Expresión Génica/genética , Herpesvirus Bovino 4/genética , Replicación Viral/genética , Animales , Bovinos , Enfermedades de los Bovinos/virología , Línea Celular , Endometrio/virología , Femenino , Infecciones por Herpesviridae/virología , Humanos , ARN Mensajero/genética , Carga Viral/genética
6.
Mult Scler ; 26(11): 1329-1339, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-31368393

RESUMEN

BACKGROUND: Substantial progress has been made toward unraveling the genetic architecture of multiple sclerosis (MS) within populations of European ancestry, but few genetic studies have focused on Hispanic and African American populations within the United States. OBJECTIVE: We sought to test the relevance of common European MS risk variants outside of the major histocompatibility complex (n = 200) within these populations. METHODS: Genotype data were available on 2652 Hispanics (1298 with MS, 1354 controls) and 2435 African Americans (1298 with MS, 1137 controls). We conducted single variant, pathway, and cumulative genetic risk score analyses. RESULTS: We found less replication than statistical power suggested, particularly among African Americans. This could be due to limited correlation between the tested and causal variants within the sample or alternatively could indicate allelic and locus heterogeneity. Differences were observed between pathways enriched among the replicating versus all 200 variants. Although these differences should be examined in larger samples, a potential role exists for gene-environment or gene-gene interactions which alter phenotype differentially across racial and ethnic groups. Cumulative genetic risk scores were associated with MS within each study sample but showed limited diagnostic capability. CONCLUSION: These findings provide a framework for fine-mapping efforts in multi-ethnic populations of MS.


Asunto(s)
Negro o Afroamericano , Esclerosis Múltiple , Negro o Afroamericano/genética , Alelos , Variación Genética , Hispánicos o Latinos/genética , Humanos , Esclerosis Múltiple/genética , Polimorfismo de Nucleótido Simple , Estados Unidos/epidemiología
7.
Proc Biol Sci ; 286(1911): 20191083, 2019 09 25.
Artículo en Inglés | MEDLINE | ID: mdl-31530147

RESUMEN

Many birds vocalize in flight. Because wingbeat and respiratory cycles are often linked in flying vertebrates, birds in these cases must satisfy the respiratory demands of vocal production within the physiological limits imposed by flight. Using acoustic triangulation and high-speed video, we found that avian vocal production in flight exhibits a largely phasic and kinematic relationship with the power stroke. However, the sample of species showed considerable flexibility, especially those from lineages known for vocal plasticity (songbirds, parrots and hummingbirds), prompting a broader phylogenetic analysis. We thus collected data from 150 species across 12 avian orders and examined the links between wingbeat period, flight call duration and body mass. Overall, shorter wingbeat periods, controlling for ancestry and body mass, were correlated with shorter flight call durations. However, species from vocal learner lineages produced flight signals that, on average, exceeded multiple phases of their wingbeat cycle, while vocal non-learners had signal periods that were, on average, closer to the duration of their power stroke. These results raise an interesting question: is partial emancipation from respiratory constraints a necessary step in the evolution of vocal learning or an epiphenomenon? Our current study cannot provide the answer, but it does suggest several avenues for future research.


Asunto(s)
Aves/fisiología , Vuelo Animal/fisiología , Animales , Fenómenos Biomecánicos , Loros , Filogenia , Pájaros Cantores , Alas de Animales/fisiología
8.
Br J Dermatol ; 181(6): 1287-1295, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-30920647

RESUMEN

BACKGROUND: There is increasing evidence of the key role that the gut microbiota plays in inflammatory diseases. OBJECTIVES: To identify differences in the faecal microbial composition of patients with psoriasis compared with healthy individuals in order to unravel the microbiota profiling in this autoimmune disease. METHODS: 16S rRNA gene sequencing and bioinformatic analyses were performed with the total DNA extracted from the faecal microbiota of 19 patients with psoriasis and 20 healthy individuals from the same geographic location. RESULTS: Gut microbiota composition of patients with psoriasis displayed a lower diversity and different relative abundance of certain bacterial taxa compared with healthy individuals. CONCLUSIONS: The gut microbiota profile of patients with psoriasis displayed a clear dysbiosis that can be targeted for microbiome-based therapeutic approaches. What's already known about this topic? Psoriasis is a chronic inflammatory immune-mediated skin disease, the aetiology of which remains unclear. The human microbiota is a complex microbial community that inhabits our body and has been related with the maintenance of a healthy status. Several studies have focused on the skin microbiome and its connection with psoriasis although less attention has been focused on the potential role of the gut microbiota in psoriatic disease. What does this study add? This study unravels the gut microbiome dysbiosis present in a cohort of patients with psoriasis, compared with a healthy control group from the same geographical location. This study shows a lower bacterial diversity and different relative abundance of certain bacterial taxa in patients with psoriasis. We gain knowledge and insight into the microbiome alterations in psoriatic disease, opening new avenues for therapeutic approaches to reshape the human microbiome towards a healthy status.


Asunto(s)
Disbiosis/complicaciones , Microbioma Gastrointestinal/inmunología , Psoriasis/inmunología , Adulto , Estudios de Cohortes , ADN Bacteriano/aislamiento & purificación , Disbiosis/diagnóstico , Disbiosis/inmunología , Disbiosis/microbiología , Heces/microbiología , Femenino , Microbioma Gastrointestinal/genética , Voluntarios Sanos , Humanos , Masculino , Persona de Mediana Edad , Psoriasis/microbiología , ARN Ribosómico 16S/genética
9.
J Environ Manage ; 246: 472-483, 2019 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-31200181

RESUMEN

Excessive fluoride content in groundwater can cause serious risks to human health, and sources of groundwater intended for human consumption should be treated to reduce fluoride concentrations down to acceptable levels. In the particular case of the island of Tenerife (Canary Islands, Spain), the water supply comes mainly from aquifers of volcanic origin with a high content of fluorides that make them unacceptable for human consumption without prior conditioning treatment. The treatments that generate a high rejection of water are not acceptable because water is a scarce natural resource of high value. An electrocoagulation process was investigated as a method to treat natural groundwater from volcanic soils containing a hazardously high fluoride content. The operating parameters of an electrocoagulation reactor model with parallel plate aluminum electrodes were optimized for batch and continuous flow operations. In the case of the batch operation, acidification of the water improved the removal efficiency of fluoride, which was the highest at pH 3. However, operation at the natural pH of the water achieved elimination efficiencies between 82 and 92%, depending on the applied current density. An optimum current density of 5 mA/cm2 was found in terms of maximum removal efficiency, and the kinetics of fluoride removal conformed to pseudo-second-order kinetics. In the continuous-flow operation, with the optimal residence time of 10 min and a separation of 0.5 cm between the electrodes, it was observed that the current density that would be applied would depend on the initial concentration of fluoride in the raw water. Thus, an initial fluoride concentration of 6.02 mg/L required a current density >7.5 mA/cm2 to comply with the legal guidelines in the product water, while for an initial concentration of 8.98 mg/L, the optimal current density was 10 mA/cm2. Under these operating conditions, the electrocoagulation process was able to reduce the fluoride concentration of natural groundwater to below 1.5 mg/L according to WHO guidelines with an operating cost between 0.20 and 0.26 €/m3 of treated water.


Asunto(s)
Agua Subterránea , Contaminantes Químicos del Agua , Purificación del Agua , Electrocoagulación , Electrodos , Fluoruros , Humanos , Concentración de Iones de Hidrógeno , España
10.
Int J Colorectal Dis ; 33(5): 649-655, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29546560

RESUMEN

PURPOSE: Compared with the open approach, laparoscopic total mesorectal excision (TME) achieves faster patient recovery, reduces morbidity rates, and shortens hospital stay. However, in laparoscopic low anterior resection (L-LAR), conversion to open surgery is required in almost 20% of cases. Transanal TME (Ta-TME) combined with laparoscopy, also called hybrid natural orifice transluminal endoscopic surgery (NOTES), is a less invasive procedure that can overcome some of the limitations of laparoscopic rectal surgery. In this study, we aim to determine whether Ta-TME has a lower rate of conversion to open surgery than L-LAR, and thus achieves faster patient recovery without altering the pathological, functional, or oncological results. The main objective is to compare the results for conversion to open surgery between Ta-TME and L-LAR. METHODS: Multicenter, prospective randomized controlled study of patients diagnosed with rectal adenocarcinoma who will be randomly allocated to Ta-TME or L-LAR groups after the application of inclusion and exclusion criteria. The main endpoint is conversion to open surgery and the secondary endpoints are general morbidity and mortality and hospital stay. Demographic, surgical, and pathological variables will also be studied, along with quality of life and survival. A sample size of 53 patients per group is calculated. With an estimated loss of 10%, the final sample required will be 116 patients. CONCLUSIONS: Ta-TME achieves a lower conversion rate to open surgery than L-LAR, thus improving patient recovery and reducing overall morbidity. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02550769. Registration no. Ethical and Clinical Research Committee, Parc Taulí University Hospital: ID 2014/064.


Asunto(s)
Canal Anal/cirugía , Procedimientos Quirúrgicos del Sistema Digestivo/métodos , Laparoscopía , Neoplasias del Recto/cirugía , Determinación de Punto Final , Estudios de Seguimiento , Humanos , Consentimiento Informado , Estudios Prospectivos , Tamaño de la Muestra
11.
Int J Colorectal Dis ; 33(2): 241-249, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29234923

RESUMEN

PURPOSE: The standard treatment of rectal adenocarcinoma is total mesorectal excision (TME), in many cases requires a temporary or permanent stoma. TME is associated with high morbidity and genitourinary alterations. Transanal endoscopic microsurgery (TEM) allows access to tumors up to 20 cm from the anal verge, achieves minimal postoperative morbidity and mortality rates, and does not require an ostomy. The treatment of T2, N0, and M0 cancers remains controversial. Preoperative chemoradiotherapy (CRT) in association with TEM reduces local recurrence and increases survival. The TAU-TEM study aims to demonstrate the non-inferiority of the oncological outcomes and the improvement in morbidity and quality of life achieved with TEM compared with TME. METHODS: Prospective, multicenter, randomized controlled non-inferiority trial includes patients with rectal adenocarcinoma less than 10 cm from the anal verge and up to 4 cm in size, staged as T2 or T3-superficial N0-M0. Patients will be randomized to two areas: CRT plus TEM or radical surgery (TME). Postoperative morbidity and mortality will be recorded and patients will complete the quality of life questionnaires before the start of treatment, after CRT in the CRT/TEM arm, and 6 months after surgery in both arms. The estimated sample size for the study is 173 patients. Patients will attend follow-up controls for local and systemic relapse. CONCLUSIONS: This study aims to demonstrate the preservation of the rectum after preoperative CRT and TEM in rectal cancer stages T2-3s, N0, M0 and to determine the ability of this strategy to avoid the need for radical surgery (TME). TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01308190. Número de registro del Comité de Etica e Investigación Clínica (CEIC) del Hospital universitario Parc Taulí: TAU-TEM-2009-01.


Asunto(s)
Terapia Neoadyuvante , Neoplasias del Recto/patología , Neoplasias del Recto/cirugía , Estudios de Seguimiento , Humanos , Consentimiento Informado , Análisis de Intención de Tratar , Estadificación de Neoplasias , Estudios Prospectivos , Tamaño de la Muestra , Resultado del Tratamiento
12.
J Mol Evol ; 84(4): 214-224, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28409196

RESUMEN

Tuftelin (TUFT1) is an acidic, phosphorylated glycoprotein, initially discovered in developing enamel matrix. TUFT1 is expressed in many mineralized and non-mineralized tissues. We performed an evolutionary analysis of 82 mammalian TUFT1 sequences to identify residues and motifs that were conserved during 220 million years (Ma) of evolution. We showed that 168 residues (out of the 390 residues composing the human TUFT1 sequence) are under purifying selection. Our analyses identified several, new, putatively functional domains and confirmed previously described functional domains, such as the TIP39 interaction domain, which correlates with nuclear localization of the TUFT1 protein, that was demonstrated in several tissues. We also identified several sites under positive selection, which could indicate evolutionary changes possibly related to the functional diversification of TUFT1 during evolution in some lineages. We discovered that TUFT1 and MYZAP (myocardial zonula adherens protein) share a common ancestor that was duplicated circa 500 million years ago. Taken together, these findings expand our knowledge of TUFT1 evolution and provide new information that will be useful for further investigation of TUFT1 functions.


Asunto(s)
Proteínas del Esmalte Dental/genética , Secuencia de Aminoácidos/genética , Animales , Secuencia de Bases/genética , Evolución Biológica , Secuencia Conservada/genética , Evolución Molecular , Humanos , Mamíferos/genética , Datos de Secuencia Molecular , Filogenia , Alineación de Secuencia/métodos
13.
Small ; 13(33)2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28692791

RESUMEN

A nonporous laminar coordination polymer of formula [Cu2 I2 (2-aminopyrazine)]n is prepared by direct reaction between CuI and 2-aminopyrazine, two industrially available building blocks. The fine tuning of the reaction conditions allows obtaining [Cu2 I2 (2-aminopyrazine)]n in micrometric and nanometric sizes with same structure and composition. Interestingly, both materials show similar reversible thermo- and pressure-luminescent response as well as reversible electrical response to volatile organic solvents such as acetic acid. X-ray diffraction studies under different conditions, temperatures and pressures, in combination with theoretical calculations allow rationalizing the physical properties of this compound and its changes under physical stimuli. Thus, the emission dramatically increases when lowering the temperature, while an enhancement of the pressure produces a decrease in the emission intensity. These observations emerge as a direct consequence of the high structural flexibility of the Cu2 I2 chains which undergo a contraction in CuCu distances as far as temperature decreases or pressure increases. However, the strong structural changes observed under high pressure lead to an unexpected effect that produces a less effective CuCu orbital overlapping that justifies the decrease in the intensity emission. This work shows the high potential of materials based on Cu2 I2 chains for new applications.

14.
Inorg Chem ; 54(22): 10738-47, 2015 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-26501154

RESUMEN

The properties recently reported on the Cu(I)-iodide pyrimidine nonporous 1D-coordination polymer [CuI(ANP)]n (ANP = 2-amino-5-nitropyridine) showing reversible physically and chemically driven electrical response have prompted us to carry a comparative study with the series of [CuX(ANP)]n (X = Cl (1), X = Br (2), X = CN (4), and X = SCN (5)) in order to understand the potential influence of the halide and pseudohalide bridging ligands on the physical properties and their electrical response to vapors of these materials. The structural characterization of the series shows a common feature, the presence of -X-Cu(ANP)-X- (X = Cl, Br, I, SCN) double chain structure. Complex [Cu(ANP)(CN)]n (4) presents a helical single chain. Additionally, the chains show supramolecular interlinked interactions via hydrogen bonding giving rise to the formation of extended networks. Their luminescent and electrical properties have been studied. The results obtained have been correlated with structural changes. Furthermore, the experimental and theoretical results have been compared using the density functional theory (DFT). The electrical response of the materials has been evaluated in the presence of vapors of diethyl ether, dimethyl methylphosphonate (DMMP), CH2Cl2, HAcO, MeOH, and EtOH, to build up simple prototype devices for gas detectors. Selectivity toward gases consisting of molecules with H-bonding donor or acceptor groups is clearly observed. This selective molecular recognition is likely due to the 2-amino-5-nitropyridine terminal ligand.

15.
J Dairy Sci ; 98(6): 3622-32, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25841972

RESUMEN

A total of 34 lactic acid bacteria isolates from 4 different Brazilian kefir grains were identified and characterized among a group of 150 isolates, using the ability to tolerate acidic pH and resistance to bile salts as restrictive criteria for probiotic potential. All isolates were identified by amplified ribosomal DNA restriction analysis and 16S rDNA sequencing of representative amplicons. Eighteen isolates belonged to the species Leuconostoc mesenteroides, 11 to Lactococcus lactis (of which 8 belonged to subspecies cremoris and 3 to subspecies lactis), and 5 to Lactobacillus paracasei. To exclude replicates, a molecular typing analysis was performed by combining repetitive extragenic palindromic-PCR and random amplification of polymorphic DNA techniques. Considering a threshold of 90% similarity, 32 different strains were considered. All strains showed some antagonistic activity against 4 model food pathogens. In addition, 3 Lc. lactis strains and 1 Lb. paracasei produced bacteriocin-like inhibitory substances against at least 2 indicator organisms. Moreover, 1 Lc. lactis and 2 Lb. paracasei presented good total antioxidative activity. None of these strains showed undesirable enzymatic or hemolytic activities, while proving susceptible or intrinsically resistant to a series of clinically relevant antibiotics. The Lb. paracasei strain MRS59 showed a level of adhesion to human Caco-2 epithelial cells comparable with that observed for Lactobacillus rhamnosus GG. Taken together, these properties allow the MRS59 strain to be considered a promising probiotic candidate.


Asunto(s)
Productos Lácteos Cultivados/microbiología , Microbiología de Alimentos , Lactobacillaceae/aislamiento & purificación , Lactobacillaceae/fisiología , Leuconostoc/aislamiento & purificación , Probióticos , Animales , Adhesión Bacteriana/fisiología , Brasil , Células CACO-2 , ADN Ribosómico , Humanos , Leuconostoc/fisiología , Reacción en Cadena de la Polimerasa/métodos
16.
Rev Med Chil ; 142(2): 153-60, 2014 Feb.
Artículo en Español | MEDLINE | ID: mdl-24953102

RESUMEN

BACKGROUND: There is increasing interest in the study and improvement of health system resource allocation. The Adjusted Clinical Groups (ACG) System measures the morbidity burden of patient populations based on disease patterns, age and gender. This system can be used in primary health care settings. AIM: To report the use of the ACG system as a risk based patient classification system and its potential as a resource allocation mechanism in primary health care. MATERIAL AND METHODS: Patient diagnoses from a sample of primary care establishments were processed using the Johns Hopkins ACG System. Linear regressions were used to measure the ACG System's ability to explain resource use and ambulatory visit rates. RESULTS: The ACG System had a statistically significant capacity to explain primary health care costs with an adjusted R² of 0.26. These results are significantly better, compared with risk assessment models based on patients' age and sex, whose adjusted R² is 0.05. CONCLUSIONS: The use of risk adjustment mechanisms will contribute to improve health care resource allocation as well to know the disease profile of the population.


Asunto(s)
Grupos Diagnósticos Relacionados , Atención Primaria de Salud/economía , Asignación de Recursos , Chile , Femenino , Humanos , Modelos Lineales , Masculino , Proyectos Piloto , Medición de Riesgo
17.
Nat Genet ; 27(4): 435-8, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11279528

RESUMEN

Most human sequence variation is in the form of single-nucleotide polymorphisms (SNPs). It has been proposed that coding-region SNPs (cSNPs) be used for direct association studies to determine the genetic basis of complex traits. The success of such studies depends on the frequency of disease-associated alleles, and their distribution in different ethnic populations. If disease-associated alleles are frequent in most populations, then direct genotyping of candidate variants could show robust associations in manageable study samples. This approach is less feasible if the genetic risk from a given candidate gene is due to many infrequent alleles. Previous studies of several genes demonstrated that most variants are relatively infrequent (<0.05). These surveys genotyped small samples (n<75) and thus had limited ability to identify rare alleles. Here we evaluate the prevalence and distribution of such rare alleles by genotyping an ethnically diverse reference sample that is more than six times larger than those used in previous studies (n=450). We screened for variants in the complete coding sequence and intron-exon junctions of two candidate genes for neuropsychiatric phenotypes: SLC6A4, encoding the serotonin transporter; and SLC18A2, encoding the vesicular monoamine transporter. Both genes have unique roles in neuronal transmission, and variants in either gene might be associated with neurobehavioral phenotypes.


Asunto(s)
Frecuencia de los Genes , Pruebas Genéticas , Alelos , Cartilla de ADN , Humanos , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Polimorfismo de Nucleótido Simple
18.
Rev Med Chil ; 141(3): 332-7, 2013 Mar.
Artículo en Español | MEDLINE | ID: mdl-23900324

RESUMEN

BACKGROUND: Efficiency in the use of resources in health systems and hospitals has been a matter of interest for administrators as well as for policy makers. The growing costs due to higher levels of demand from the population require a better use and allocation of such costs. AIM: To assess the technical efficiency in 28 hospitals in Chile, considering the period from May to October, 2011. MATERIAL AND METHODS: The average number of available beds, the number of staff and the expenses on consumer and service goods were used as production inputs and, on the other hand, the expenditures adjusted by the Diagnosis-Related Groups (IR-DRG) were used as producís. To assess the technical efficiency, the Data Envelopment Analysis technique was used. RESULTS: The levéis of inefficiency fluctuóte from 20 to 23.3%. In other words, with a 20% increase in hospital discharges and maintaining fixed inputs, hospitals could become efficient. CONCLUSIONS: The incorporation of methodologies to determine efficiency allows gathering new knowledge for people who manage resources as well as for policy makers by optimizing practices and having better allocation criteria.


Asunto(s)
Eficiencia Organizacional/normas , Asignación de Recursos para la Atención de Salud/estadística & datos numéricos , Recursos en Salud/estadística & datos numéricos , Hospitales/normas , Benchmarking , Chile , Grupos Diagnósticos Relacionados , Eficiencia Organizacional/estadística & datos numéricos , Asignación de Recursos para la Atención de Salud/normas , Recursos en Salud/normas , Hospitales/estadística & datos numéricos , Humanos , Modelos Teóricos , Calidad de la Atención de Salud/estadística & datos numéricos
19.
Rev Med Chil ; 141(4): 457-63, 2013 Apr.
Artículo en Español | MEDLINE | ID: mdl-23900366

RESUMEN

BACKGROUND: The knowledge of variables influencing hospital efficiency is of paramount importance to carry out initiatives of management improvement and optimization. AIM: To explore on the hospital technical efficiency factors. MATERIAL AND METHODS: Data from 255,439 hospital discharges from 28 hospitals from May to October 2011 were analyzed. The efficiency index developed by Santelices et al was calculated. Proxy variables of hospital practices, human resource productivity, strategic performance, financing mechanisms, geographical territory and specialization, were considered. The analysis was carried out estimating econometric models. RESULTS: The most significant variables to explain efficiency are the length of stay adjusted by complexity, the discharges per nurse and midwife and the performance of the Hospital Balancea Score Card. CONCLUSIONS: The suggested analysis contributes to identify hospital efficiency causes. The results suggest ways to improve performance of hospitals.


Asunto(s)
Eficiencia Organizacional , Administración Hospitalaria , Chile , Economía Hospitalaria , Humanos , Tiempo de Internación , Modelos Econométricos
20.
J Wrist Surg ; 12(4): 377-382, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37564625

RESUMEN

Background Synovial cysts (SCs) are the most frequent wrist tumors; the arthroscopic treatment presents good results when surgery is indicated for symptomatic or patients with cosmetic concerns. The tumoral lesion should be arthroscopically decompressed or drained toward the inside of the joint through pedicle opening and resection of a small portion of the capsule. Hence, the cyst pedicle must be found for the success of this technique. Description of Technique Some tricks have already been described to facilitate SC location during arthroscopy. We describe an indirect technique that employs an 18-G needle to enhance SC pedicle location and drainage. The technique involves a puncture on the interval of the carpal extrinsic ligaments where the pedicle is suspected to be remain. When found, cyst is drained with a single-puncture motion of the need which promotes cyst content extravasation due to pressure toward the joint. Patients and Methods This method has been employed in 16 patients, including 9 with dorsal cysts, and seven with volar cysts. Results All patients presented complete recovery and symptom improvement in up to 30 days, with total disappearance of the cyst. There were no relapses or severe complications within the 12-month follow-up. Conclusion This is a safe, useful technique that facilitates location of intra-articular cyst pedicle, thus avoiding unnecessary damage in healthy tissues with no increased costs.

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