21 results on '"Belmar C"'
Search Results
2. Cocinando relaciones interculturales: Residuos adheridos en vasijas ceramicas de grupos cazadores recolectores marinos del desierto de Atacama (período formativo, norte de Chile)
- Author
-
Gallardo, Francisco, Carrasco. M., Corre, I., Belmar, C., and Ballester, B.
- Abstract
Food has different meanings that go way beyond its nourishing nutritional and metabolic properties. Behind this concept, there is a rich source of supplies for the construction of social ties and distinctions, along with different cultural identities. Hun
- Published
- 2017
3. The Effect of CO2 Availability on the Growth, Iron Oxidation and CO2-Fixation Rates of Pure Cultures of Leptospirillum ferriphilum and Acidithiobacillus ferrooxidans
- Author
-
Bryan, C G, Davis-Belmar, C S, van Wyk, N, Fraser, M K, Dew, D, Rautenbach, G F, and Harrison, S T L
- Subjects
Bioleaching ,Growth rate ,Acidithiobacillus ferrooxidans ,CO2-fixation ,Iron oxidation - Abstract
Understanding how bioleaching systems respond to the availability of CO2 is essential to developing operating conditions that select for optimum microbial performance. Therefore, the effect of inlet gas and associated dissolved CO2 concentration on the growth, iron oxidation and CO2-fixation rates of pure cultures of Acidithiobacillus ferrooxidans and Leptospirillum ferriphilum was investigated in a batch stirred tank system. The minimum inlet CO2 concentrations required to promote the growth of At. ferrooxidans and L. ferriphilum were 25 and 70 ppm, respectively, and corresponded to dissolved CO2 concentrations of 0.71 and 1.57 mM (at 308C and 378C, respectively). An actively growing culture of L. ferriphilum was able to maintain growth at inlet CO2 concentrations less than 30 ppm (0.31–0.45 mM in solution). The highest total new cell production and maximum specific growth rates from the stationary phase inocula were observed with CO2 inlet concentrations less than that of air. In contrast, the amount of CO2 fixed per new cell produced increased with increasing inlet CO2 concentrations above 100 ppm. Where inlet gas CO2 concentrations were increased above that of air the additional CO2 was consumed by the organisms but did not lead to increased cell production or significantly increase performance in terms of iron oxidation. It is proposed that At. ferrooxidans has two CO2 uptake mechanisms, a high affinity system operating at low available CO2 concentrations, which is subject to substrate inhibition and a low affinity system operating at higher available CO2 concentrations. L. ferriphilum has a single uptake system characterised by a moderate CO2 affinity. At. ferrooxidans performed better than L. ferriphilum at lower CO2 availabilities, and was less affected by CO2 starvation. Finally, the results demonstrate the limitations of using CO2 uptake or ferrous iron oxidation data as indirect measures of cell growth and performance across varying physiological conditions. Biotechnol. Bioeng. 2012;109: 1693–1703
- Published
- 2012
- Full Text
- View/download PDF
4. Plasma prolactin/oestradiol ratio at 38 weeks gestation predicts the duration of lactational amenorrhoea.
- Author
-
Campino, Carmen, Torres, Claudia, Rioseco, Alonso, Poblete, Andrés, Pugin, Edda, Valdés, Verónica, Catalán, Silvia, Belmar, Cristián, Serón-Ferré, María, Campino, C, Torres, C, Rioseco, A, Poblete, A, Pugin, E, Valdés, V, Catalán, S, Belmar, C, and Serón-Ferré, M
- Abstract
Background: Fully breastfeeding women experience an amenorrhoea of variable duration. Our aim was to identify in pregnancy, endocrine markers that could predict the duration of subsequent lactational amenorrhoea.Methods: We studied 17 healthy women at 34 and 38 weeks gestation, and 1 and 3 months post-partum. The women fully breastfed until 6 months post-partum. During pregnancy, prolactin (PRL), oestrogens (total oestradiol, unconjugated oestrone, unconjugated oestriol), sex hormone binding globulin (SHBG), dehydroepiandrosterone sulphate (DHEA-S), progesterone and placental lactogen, and during post-partum PRL, oestrogens and SHBG, were measured. Free oestradiol in pregnancy and post-partum was calculated.Results: Ten women experienced long (>6 months) and seven experienced short (<6 months) lactational amenorrhoea. At 38 weeks gestation, the women who experienced a long lactational amenorrhoea had twice as much PRL, about half the total oestradiol, lower SHBG concentration (P < 0.05, Student's t-test, Bonferroni modification) and similar free oestradiol concentration, compared with those who experienced short lactational amenorrhoea. The difference in PRL concentration persisted in post-partum postsuckling samples.Conclusion: At 38 weeks gestation, the ratio PRL/oestradiol identified all individual women according to the subsequent duration of their lactational amenorrhoea, suggesting that duration of lactational amenorrhoea is conditioned during pregnancy. [ABSTRACT FROM AUTHOR]- Published
- 2001
- Full Text
- View/download PDF
5. An Intrinsic Host Defense against HSV-1 Relies on the Activation of Xenophagy with the Active Clearance of Autophagic Receptors.
- Author
-
Pino-Belmar C, Aguilar R, Valenzuela-Nieto GE, Cavieres VA, Cerda-Troncoso C, Navarrete VC, Salazar P, Burgos PV, Otth C, and Bustamante HA
- Subjects
- Humans, Herpes Simplex virology, Herpes Simplex immunology, Herpes Simplex metabolism, Macroautophagy, Virus Replication, Autophagosomes metabolism, Keratinocytes virology, Keratinocytes metabolism, Sequestosome-1 Protein metabolism, Host-Pathogen Interactions, Animals, Nuclear Proteins, Cell Cycle Proteins, Membrane Transport Proteins, Herpesvirus 1, Human physiology, Autophagy
- Abstract
Autophagy engulfs cellular components in double-membrane-bound autophagosomes for clearance and recycling after fusion with lysosomes. Thus, autophagy is a key process for maintaining proteostasis and a powerful cell-intrinsic host defense mechanism, protecting cells against pathogens by targeting them through a specific form of selective autophagy known as xenophagy. In this context, ubiquitination acts as a signal of recognition of the cargoes for autophagic receptors, which direct them towards autophagosomes for subsequent breakdown. Nevertheless, autophagy can carry out a dual role since numerous viruses including members of the Orthoherpesviridae family can either inhibit or exploit autophagy for its own benefit and to replicate within host cells. There is growing evidence that Herpes simplex virus type 1 (HSV-1), a highly prevalent human pathogen that infects epidermal keratinocytes and sensitive neurons, is capable of negatively modulating autophagy. Since the effects of HSV-1 infection on autophagic receptors have been poorly explored, this study aims to understand the consequences of HSV-1 productive infection on the levels of the major autophagic receptors involved in xenophagy, key proteins in the recruitment of intracellular pathogens into autophagosomes. We found that productive HSV-1 infection in human neuroglioma cells and keratinocytes causes a reduction in the total levels of Ub conjugates and decreases protein levels of autophagic receptors, including SQSTM1/p62, OPTN1, NBR1, and NDP52, a phenotype that is also accompanied by reduced levels of LC3-I and LC3-II, which interact directly with autophagic receptors. Mechanistically, we show these phenotypes are the result of xenophagy activation in the early stages of productive HSV-1 infection to limit virus replication, thereby reducing progeny HSV-1 yield. Additionally, we found that the removal of the tegument HSV-1 protein US11, a recognized viral factor that counteracts autophagy in host cells, enhances the clearance of autophagic receptors, with a significant reduction in the progeny HSV-1 yield. Moreover, the removal of US11 increases the ubiquitination of SQSTM1/p62, indicating that US11 slows down the autophagy turnover of autophagy receptors. Overall, our findings suggest that xenophagy is a potent host defense against HSV-1 replication and reveals the role of the autophagic receptors in the delivery of HSV-1 to clearance via xenophagy.
- Published
- 2024
- Full Text
- View/download PDF
6. Association between eating habits and quality of life among Chilean university students.
- Author
-
Lanuza F, Morales G, Hidalgo-Rasmussen C, Balboa-Castillo T, Ortiz MS, Belmar C, and Muñoz S
- Subjects
- Adolescent, Chile, Cross-Sectional Studies, Humans, Surveys and Questionnaires, Universities, Young Adult, Feeding Behavior, Quality of Life, Students
- Abstract
Objective To estimate the association between eating habits and quality of life (QOL) in Chilean university students. Participants: 1,212 students from the Universidad de La Frontera, Chile (mean age 18.7 ± 2.15) were surveyed in January-March 2018. Methods: Participants completed a cross-sectional self-report survey to evaluate QOL using the WHOQOL-BREF scale and eating habits with a food habits survey. Results: Students reporting a better healthy eating habits score also presented a higher QOL. Eating breakfast and eating home-cooked meals is a protective factor for QOL in each domain. The consumption of sweet snacks was shown to be a risk factor for the physical health and environment domains. The consumption of fast food is shown as the greatest risk factor in the physical domain. Conclusion: Healthy and unhealthy eating habits are associated with different dimensions of QOL. University authorities should develop new policies to improve the QOL of the entire university community.
- Published
- 2022
- Full Text
- View/download PDF
7. Chemical Characterization of Lavandula dentata Essential Oil Cultivated in Chile and Its Antibiofilm Effect against Candida albicans.
- Author
-
Müller-Sepúlveda A, Chevecich CC, Jara JA, Belmar C, Sandoval P, Meyer RS, Quijada R, Moura S, López-Muñoz R, Díaz-Dosque M, and Molina-Berríos A
- Subjects
- Antifungal Agents pharmacology, Biofilms, Candida albicans, Chile, Humans, Microbial Sensitivity Tests, Lavandula, Oils, Volatile pharmacology
- Abstract
Candida albicans is the most common human fungal pathogen, and with the increase in resistance rates worldwide, it is necessary to search for new pharmacological alternatives. Lavandula dentata L. essential oil is recognized as having antimicrobial properties. However, its effect against fungal biofilms has been poorly described. C. albicans -related infections involve the development of biofilms, which are highly resistant to conventional antifungals. In this work, we evaluated the antibiofilm effect of L. dentata L. essential oil against C. albicans. First, we characterized the essential oil by gas chromatography-mass spectrometry. The antifungal effect on C. albicans reference strains was evaluated by a disk diffusion assay and the minimal inhibitory concentration was obtained through a microdilution assay. The effect of the essential oil on the adhesion ability of C. albicans was determined through a crystal violet assay, and morphogenesis inhibition was assessed by light microscopy. The effect of the essential oil on the microarchitecture of biofilms was evaluated through scanning electron microscopy. Finally, the antibiofilm effect was evaluated through an adapted biofilm scratch assay and XTT viability assay. The main constituent of the essential oil was the monoterpenoid eucalyptol (60%). The essential oil presented minimal inhibitory concentrations of 156 and 130 µg/mL against two strains assayed. This minimal inhibitory concentration inhibited adhesion, morphogenesis, biofilm formation, altered microarchitecture, and decreased the viability of established biofilms formed on abiotic surfaces for both strains assayed. This study demonstrates that the essential oil from L. dentata could be a promising treatment against C. albicans biofilms., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)
- Published
- 2020
- Full Text
- View/download PDF
8. Sclerosing angiomatoid nodular transformation of the spleen: unusual case presentation in an intravenous drug user.
- Author
-
Sánchez Belmar C, White A, Majeed M, and Redmond HP
- Subjects
- Adult, Angiomatosis chemically induced, Humans, Male, Sclerosis, Splenic Diseases chemically induced, Substance Abuse, Intravenous complications, Angiomatosis pathology, Spleen pathology, Splenic Diseases pathology, Substance Abuse, Intravenous pathology
- Abstract
An unusual presentation of sclerosing angiomatoid nodular transformation in a 42-year-old man who was admitted with jaundice, deranged liver function tests and subsequently diagnosed with acute hepatitis C infection in the context of recent intravenous drug use. During his admission, he had an ultrasound of the abdomen followed by a CT thorax, abdomen and pelvis which showed splenomegaly and a large splenic lower pole mass that was hypoechoic and concerning for lymphoma. A bone marrow biopsy showed no evidence of lymphoma and an ultrasound-guided biopsy of the splenic mass suggested unusual features with vascular proliferation, either neoplastic or reactive, with no evidence of lymphoma or high-grade sarcoma. Given the concern for malignancy, an open splenectomy was required to determine the nature of the lesion with histologic findings consistent with a non-neoplastic benign vascular lesion favouring sclerosing angiomatoid nodular transformation., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2020. No commercial re-use. See rights and permissions. Published by BMJ.)
- Published
- 2020
- Full Text
- View/download PDF
9. Correction to: A thiotrophic microbial community in an acidic brine lake in Northern Chile.
- Author
-
Escudero L, Oetiker N, Gallardo K, Tebes-Cayo C, Guajardo M, Nuñez C, Davis-Belmar C, Pueyo JJ, Díaz GC, and Demergasso C
- Abstract
In Table 1 of the original article, the unit mg/L was incorrectly published as ng/L in the aluminum, chloride, sulphate and OM columns.
- Published
- 2018
- Full Text
- View/download PDF
10. A thiotrophic microbial community in an acidic brine lake in Northern Chile.
- Author
-
Escudero L, Oetiker N, Gallardo K, Tebes-Cayo C, Guajardo M, Nuñez C, Davis-Belmar C, Pueyo JJ, Chong Díaz G, and Demergasso C
- Subjects
- Bacteria metabolism, Biodiversity, Carbon Cycle, Chile, DNA, Bacterial genetics, Energy Metabolism, Geologic Sediments microbiology, Metagenomics, RNA, Ribosomal, 16S genetics, Bacteria classification, Lakes microbiology, Phylogeny, Salts, Sulfur metabolism
- Abstract
The endorheic basins of the Northern Chilean Altiplano contain saline lakes and salt flats. Two of the salt flats, Gorbea and Ignorado, have high acidic brines. The causes of the local acidity have been attributed to the occurrence of volcanic native sulfur, the release of sulfuric acid by oxidation, and the low buffering capacity of the rocks in the area. Understanding the microbial community composition and available energy in this pristine ecosystem is relevant in determining the origin of the acidity and in supporting the rationale of conservation policies. Besides, a comparison between similar systems in Australia highlights key microbial components and specific ones associated with geological settings and environmental conditions. Sediment and water samples from the Salar de Gorbea were collected, physicochemical parameters measured and geochemical and molecular biological analyses performed. A low diversity microbial community was observed in brines and sediments dominated by Actinobacteria, Algae, Firmicutes and Proteobacteria. Most of the constituent genera have been reported to be either sulfur oxidizing microorganisms or ones having the potential for sulfur oxidation given available genomic data and information drawn from the literature on cultured relatives. In addition, a link between sulfur oxidation and carbon fixation was observed. In contrast, to acid mine drainage communities, Gorbea microbial diversity is mainly supported by chemolithoheterotrophic, facultative chemolithoautotrophic and oligotrophic sulfur oxidizing populations indicating that microbial activity should also be considered as a causative agent of local acidity.
- Published
- 2018
- Full Text
- View/download PDF
11. Preventive letter: doubling the return rate after gestational diabetes mellitus.
- Author
-
Olmos PR, Borzone GR, Berkowitz L, Mertens N, Busso D, Santos JL, Poblete JA, Vera C, Belmar C, Goldenberg D, Samith B, Acosta AM, and Escalona M
- Subjects
- Adult, Amino Acids, C-Peptide blood, Chile, Chromium, Diabetes, Gestational blood, Diabetes, Gestational therapy, Female, Humans, Kaplan-Meier Estimate, Nicotinic Acids, Postnatal Care methods, Pregnancy, Schools, Medical, Correspondence as Topic, Diabetes Mellitus, Type 2 prevention & control, Health Promotion methods, Health Promotion statistics & numerical data, Patient Compliance statistics & numerical data
- Abstract
To measure the impact of a "Preventive Letter" designed to encourage the return of gestational diabetes mellitus (GDM) mothers to follow up visit after delivery, in the context of a worldwide concern about low return rates after delivery of these patients. Mothers with GDM require medical evaluation and an oral glucose tolerance test (OGTT) 6 weeks after delivery, in order to: [a] confirm remission of GDM and [b] provide advice on the prevention of type 2 diabetes. In the year 2003 we developed a "Preventive Letter", containing three aspects: [a] current treatment, [b] suggested management during labor, and [c] a stapled laboratory order for OGTT to be performed 6 weeks after delivery. The return rate after delivery was assessed in two groups of GDM mothers: [a] "Without Preventive Letter" (n = 253), and "With Preventive Letter" (n = 215). Both groups, similar with respect to age (33.0 ± 5.4 and 32.3 ± 4.9 years respectively, p = 0.166) and education time (14.9 ± 1.8 and 15.0 ± 1.8 years respectively, p = 0.494), showed a significant difference in the 1-year return rate after delivery, as assessed by the Kaplan-Meier test: 32.0 % for the group "Without Preventive Letter", and 76.0 % for the group "With Preventive Letter" (p < 0.001). The 1-year return rate after delivery of GDM mothers was 2.4 times higher in the group "With Preventive Letter" than in the group without it. We believe that this low-cost approach could be useful in other institutions caring for pregnant women with diabetes.
- Published
- 2015
- Full Text
- View/download PDF
12. Maternal hypertriglyceridemia: A link between maternal overweight-obesity and macrosomia in gestational diabetes.
- Author
-
Olmos PR, Rigotti A, Busso D, Berkowitz L, Santos JL, Borzone GR, Poblete JA, Vera C, Belmar C, Goldenberg D, Samith B, Acosta AM, Escalona M, Niklitschek I, Mandiola JR, and Mertens N
- Subjects
- Adult, Body Weight, Female, Gestational Age, Humans, Infant, Newborn, Pregnancy, Prospective Studies, Diabetes, Gestational, Fetal Macrosomia etiology, Hypertriglyceridemia complications, Obesity, Pregnancy Complications
- Abstract
Objective: Infants born from overweight and obese mothers with glucose-controlled gestational diabetes (GDM) tend to be large-for-gestational age (LGA). It is hypothesized that this is due to an excessive rise in maternal triglyceride levels., Methods: Two-hundred and seventy nine singleton GDM pregnancies were divided into three groups according to prepregnancy BMI: normal weight (BMI = 20-24.9; n = 128), overweight (BMI = 25-29.9; n = 105), and obese (BMI ≥ 30; n = 46). Individual z-scores (ZS) of maternal triglycerides and of newborn weight (NWZS) were calculated as deviations from published 50th percentiles. Mean z-scores (MZS) were the average of triglyceride ZSs. MZS of triglycerides, HbA1c and NWZS were compared. Variables are expressed as mean ± SD., Results: In the three groups respectively: LGA (%) = 10.1%, 19.0% and 30.4% (P = 0.015). Birth weight (g) = 3274.2 ± 501.3, 3342.4 ± 620.2 and 3366.3±644.7 (RSPEARMAN = 0.111, P = 0.027). HbA1c (%) = 5.2 ± 0.39, 5.3 ± 0.50 and 5.4 ± 0.47 (P = NS). Triglyceride MZS = 1.20 ± 1.13, 1.52 ± 1.37 and 1.62 ± 1.42 (RSPEARMAN = 0.116, P = 0.024). Correlations between triglyceride MZS and NWZS were, respectively: r = 0.12 (P = NS), r = 0.42 (P <0.001), and r = 0.47 (P < 0.001)., Conclusions: In overweight and obese GDM mothers, maternal triglycerides are partially responsible for LGA infants despite good maternal glucose control during pregnancy., (Copyright © 2014 The Obesity Society.)
- Published
- 2014
- Full Text
- View/download PDF
13. Microbial life in a fjord: metagenomic analysis of a microbial mat in Chilean patagonia.
- Author
-
Ugalde JA, Gallardo MJ, Belmar C, Muñoz P, Ruiz-Tagle N, Ferrada-Fuentes S, Espinoza C, Allen EE, and Gallardo VA
- Subjects
- Chile, DNA, Bacterial genetics, Energy Metabolism genetics, Gammaproteobacteria classification, Gammaproteobacteria genetics, Metabolic Networks and Pathways genetics, Molecular Sequence Annotation, Molecular Typing, Phylogeny, RNA, Ribosomal, 16S genetics, Rivers, Sequence Analysis, DNA, Metagenome, Microbial Consortia genetics, Water Microbiology
- Abstract
The current study describes the taxonomic and functional composition of metagenomic sequences obtained from a filamentous microbial mat isolated from the Comau fjord, located in the northernmost part of the Chilean Patagonia. The taxonomic composition of the microbial community showed a high proportion of members of the Gammaproteobacteria, including a high number of sequences that were recruited to the genomes of Moritella marina MP-1 and Colwelliapsycherythraea 34H, suggesting the presence of populations related to these two psychrophilic bacterial species. Functional analysis of the community indicated a high proportion of genes coding for the transport and metabolism of amino acids, as well as in energy production. Among the energy production functions, we found protein-coding genes for sulfate and nitrate reduction, both processes associated with Gammaproteobacteria-related sequences. This report provides the first examination of the taxonomic composition and genetic diversity associated with these conspicuous microbial mat communities and provides a framework for future microbial studies in the Comau fjord.
- Published
- 2013
- Full Text
- View/download PDF
14. The effect of CO2 availability on the growth, iron oxidation and CO2-fixation rates of pure cultures of Leptospirillum ferriphilum and Acidithiobacillus ferrooxidans.
- Author
-
Bryan CG, Davis-Belmar CS, van Wyk N, Fraser MK, Dew D, Rautenbach GF, and Harrison ST
- Subjects
- Bioreactors, Oxidation-Reduction, Acidithiobacillus growth & development, Acidithiobacillus metabolism, Bacteria growth & development, Bacteria metabolism, Carbon Dioxide metabolism, Iron metabolism
- Abstract
Understanding how bioleaching systems respond to the availability of CO(2) is essential to developing operating conditions that select for optimum microbial performance. Therefore, the effect of inlet gas and associated dissolved CO(2) concentration on the growth, iron oxidation and CO(2) -fixation rates of pure cultures of Acidithiobacillus ferrooxidans and Leptospirillum ferriphilum was investigated in a batch stirred tank system. The minimum inlet CO(2) concentrations required to promote the growth of At. ferrooxidans and L. ferriphilum were 25 and 70 ppm, respectively, and corresponded to dissolved CO(2) concentrations of 0.71 and 1.57 µM (at 30°C and 37°C, respectively). An actively growing culture of L. ferriphilum was able to maintain growth at inlet CO(2) concentrations less than 30 ppm (0.31-0.45 µM in solution). The highest total new cell production and maximum specific growth rates from the stationary phase inocula were observed with CO(2) inlet concentrations less than that of air. In contrast, the amount of CO(2) fixed per new cell produced increased with increasing inlet CO(2) concentrations above 100 ppm. Where inlet gas CO(2) concentrations were increased above that of air the additional CO(2) was consumed by the organisms but did not lead to increased cell production or significantly increase performance in terms of iron oxidation. It is proposed that At. ferrooxidans has two CO(2) uptake mechanisms, a high affinity system operating at low available CO(2) concentrations, which is subject to substrate inhibition and a low affinity system operating at higher available CO(2) concentrations. L. ferriphilum has a single uptake system characterised by a moderate CO(2) affinity. At. ferrooxidans performed better than L. ferriphilum at lower CO(2) availabilities, and was less affected by CO(2) starvation. Finally, the results demonstrate the limitations of using CO(2) uptake or ferrous iron oxidation data as indirect measures of cell growth and performance across varying physiological conditions., (Copyright © 2012 Wiley Periodicals, Inc.)
- Published
- 2012
- Full Text
- View/download PDF
15. Functional link between adenosine and insulin: a hypothesis for fetoplacental vascular endothelial dysfunction in gestational diabetes.
- Author
-
Guzmán-Gutiérrez E, Abarzúa F, Belmar C, Nien JK, Ramírez MA, Arroyo P, Salomón C, Westermeier F, Puebla C, Leiva A, Casanello P, and Sobrevia L
- Subjects
- Animals, Endothelium, Vascular pathology, Female, Fetal Diseases etiology, Humans, Hyperinsulinism etiology, Placental Circulation, Pregnancy, Receptor, Insulin metabolism, Adenosine metabolism, Diabetes, Gestational physiopathology, Insulin metabolism
- Abstract
Gestational diabetes mellitus (GDM) is a syndrome compromising the health of the mother and the fetus. Endothelial damage and reduced metabolism of the vasodilator adenosine occur and fetal hyperinsulinemia associated with deficient insulin response and a metabolic rather than mitogenic phenotype is characteristic of this pathology. These phenomena lead to endothelial dysfunction of the fetoplacental unit. Major databases were searched for the relevant literature in the field. Special attention was placed on publications related with diabetes and hormone/metabolic disorders. We aimed to summarize the information regarding insulin sensitivity changes in GDM and the role of adenosine in this phenomenon. Evidence supporting the possibility that fetal endothelial dysfunction involves a functional link between adenosine and insulin signaling in the fetal endothelium from GDM pregnancies is summarized. Since insulin acts via membrane receptors type A (preferentially associated with mitogenic responses) or type B (preferentially associated with metabolic responses), a differential activation of these receptors in this syndrome is proposed.
- Published
- 2011
- Full Text
- View/download PDF
16. Near-optimal glycemic control in Chilean women with pregestational type-2 diabetes: persistent macrosomia relates to maternal pre-pregnancy overweight.
- Author
-
Olmos PR, Araya-Del-Pino AP, González-Carvello CA, Laso-Ulloa P, Hodgson MI, Irribarra V, Borzone GR, Belmar C, Poblete A, Berríos C, Becker J, Zajer-Amar CM, Manzur A, Bozinovic M, Miranda RJ, Diez A, Vidal H, Ramírez-Armijo R, Olmos RI, Tabilo C, and Ahuad J
- Subjects
- Birth Weight, Body Mass Index, Cesarean Section, Chile, Diabetes Mellitus, Type 1 physiopathology, Diabetes Mellitus, Type 2 physiopathology, Female, Fetal Death epidemiology, Gestational Age, Glycated Hemoglobin metabolism, Humans, Infant, Newborn, Pregnancy, Pregnancy Complications physiopathology, Diabetes Mellitus, Type 1 blood, Diabetes Mellitus, Type 2 blood, Overweight physiopathology, Pregnancy in Diabetics blood
- Abstract
Unlabelled: After a 10-year program intending to improve glycemic control in diabetic pregnancies, we evaluated whether factors underlying macrosomia are similar for type-1 and -2 pregestational diabetic women., Patients and Methods: Twenty-three pregnancies in type-1 diabetics (PDM1, age 28.3+/-1.1 years) and 51 pregnancies in type-2 diabetics (PDM2, age 32.8+/-0.6 years) were followed and treated with intensified insulin therapy. Several factors potentially influencing macrosomia were evaluated., Statistics: chi-square, Fisher's exact, Student's "t" and Mann-Whitney "U" tests, and ROC analysis., Results: In PDM1 and PDM2, respectively, large-for-gestational-age (LGA) frequencies were 26.08% and 37.25% (NS), antepartum HbA1c values were 6.5+/-0.32 and 6.1+/-0.16 (NS), and pre-pregnancy body mass indexes (BMI) were 23.03+/-0.66 and 30.01+/-0.89 (p<0.0001). In PDM1 the main predictor of LGA was an antepartum HbA1c> or =6.8% (p=0.046), whereas in PDM2 pregestational BMI> or =24 the variable associated (p=0.032) with LGA newborns., Conclusions: PDM1 and PDM2 differ in the underlying factors related to macrosomia. Whereas in PDM1 the antepartum HbA1c emerged as the most significant variable, suggesting that glycemic control largely determines macrosomia, in PDM2 with near-optimal glycemic control, macrosomia related to pregestational BMI.
- Published
- 2009
- Full Text
- View/download PDF
17. Morphologic and functional predictors of eventual circulation in the fetus with pulmonary atresia or critical pulmonary stenosis with intact septum.
- Author
-
Gardiner HM, Belmar C, Tulzer G, Barlow A, Pasquini L, Carvalho JS, Daubeney PE, Rigby ML, Gordon F, Kulinskaya E, and Franklin RC
- Subjects
- Area Under Curve, Female, Fetal Diseases diagnostic imaging, Health Status Indicators, Heart Ventricles diagnostic imaging, Heart Ventricles surgery, Humans, Infant, Newborn, Male, Models, Statistical, Postnatal Care, Predictive Value of Tests, Pregnancy, Prospective Studies, Pulmonary Atresia diagnostic imaging, Pulmonary Atresia surgery, Pulmonary Valve, Pulmonary Valve Stenosis diagnostic imaging, Pulmonary Valve Stenosis surgery, Time Factors, Fetal Diseases physiopathology, Heart Septum diagnostic imaging, Heart Ventricles physiopathology, Pulmonary Atresia physiopathology, Pulmonary Valve Stenosis physiopathology, Ultrasonography, Prenatal
- Abstract
Objectives: The purpose of this study was to determine the morphologic and physiological predictors of post-natal surgical pathway in a longitudinal series of fetuses with pulmonary atresia with intact ventricular septum (PAIVS) and/or critical pulmonary stenosis with reversal of ductal flow (CPS) using statistical modeling., Background: Pulmonary atresia with intact ventricular septum is rarely associated with chromosomal or extra cardiac malformations, so decisions about continuing a pregnancy are strongly influenced by the prediction of univentricular (UV) or biventricular (BV) circulation., Methods: Predictive scores were derived, using a combination of z-scores of fetal cardiac measurements (for femoral length) and tricuspid/mitral valve (TV/MV) ratios, to facilitate early prediction of UV or BV circulation in 21 fetuses with PAIVS (18 fetuses) or CPS (3 fetuses) between 1998 and 2004. We also assessed the predictive value of coronary fistulae and right atrial pressure (RAP) score (comprising the tricuspid valve, foramen ovale, and ductus venosus Doppler)., Results: One-half of the cohort was first assessed before 23 gestational weeks (range 15.7 to 33.7 weeks). The TV z-score was a good predictor at all gestations, but the best predictive scores for specific gestations were pulmonary valve (PV) z-score (<23 weeks), median TV z-score (<26 weeks), the combination of median PV z-score and the median TV/MV ratio (26 to 31 weeks), and the combination of median TV z-score and median TV/MV ratio (>31 weeks). The RAP score and coronary fistulae were good independent predictors: RAP score >3 predicted BV with area under the curve of 0.833, and detection of fistulae usually predicted a UV route., Conclusions: The best predictive scores for post-natal outcome in fetal PAIVS/CPS are a combination of morphologic and physiological variables, which predict a BV circulation with a sensitivity of 92% and specificity of 100% before 26 weeks.
- Published
- 2008
- Full Text
- View/download PDF
18. Fetal ECG: a novel predictor of atrioventricular block in anti-Ro positive pregnancies.
- Author
-
Gardiner HM, Belmar C, Pasquini L, Seale A, Thomas M, Dennes W, Taylor MJ, Kulinskaya E, and Wimalasundera R
- Subjects
- Adolescent, Adult, Atrioventricular Block drug therapy, Atrioventricular Block immunology, Echocardiography, Doppler, Electrocardiography, Epidemiologic Methods, Female, Fetal Diseases drug therapy, Fetal Diseases immunology, Fetal Therapies, Glucocorticoids therapeutic use, Humans, Pregnancy, Ultrasonography, Prenatal methods, Antibodies, Antinuclear blood, Atrioventricular Block diagnosis, Fetal Diseases diagnosis
- Abstract
Objective: Approximately 2.8% of pregnancies are Ro/La antibody positive. 3-15% of fetuses develop complete heart block (CHB). First-degree atrioventricular heart block (1 degrees AVB) is reported in a third of Ro/La fetuses but as most have a normal postnatal ECG this may reflect inadequacies of Doppler measurement techniques., Methods: Comparison was made between mechanical (mPR) and electrical (ePR) intervals obtained prospectively using Doppler and non-invasive fetal ECG (fECG) in 52 consecutive Ro/La pregnancies in 46 women carrying 54 fetuses in an observational study at a fetal medicine unit. 121 mPR and 37 ePR intervals were recorded in 49 Ro/La fetuses. Five were referred with CHB and excluded. ePR was measured successfully in 35/37 (94%) and mPR was measured in all cases. 1 degrees AVB was defined as PR >95% CI. Logistic regression predicted abnormal final fetal rhythm from first mPR or ePR., Results: The ePR model gave 66.7% sensitivity (6 of 8 final abnormal fetal rhythm cases were predicted correctly in fetuses >20 weeks) and 96.2% specificity. mPR gave 44.4% sensitivity (4 of 9 cases) and 88.5% specificity. Z scores for ePR (zPR) were calculated from 199 normal fetuses. The area under the receiver operator characteristic (ROC) curve was 0.88 (95% CI, 0.754 to 1.007). A cut-off of 1.65 gave a sensitivity of 87.5% and specificity of 95% for those with prolonged and normal ePR intervals, respectively., Conclusion: zPR is better than mPR at differentiating between normal and prolonged PR intervals, suggesting that fECG is the diagnostic tool of choice to investigate the natural history and therapy of conduction abnormalities in Ro/La pregnancies.
- Published
- 2007
- Full Text
- View/download PDF
19. PR interval: a comparison of electrical and mechanical methods in the fetus.
- Author
-
Pasquini L, Seale AN, Belmar C, Oseku-Afful S, Thomas MJ, Taylor MJ, Roughton M, and Gardiner HM
- Subjects
- Adult, Female, Heart Rate, Fetal, Humans, Pregnancy, Cardiotocography methods, Electrocardiography, Fetus physiology
- Abstract
Background: Mechanical surrogates are used to assess fetal cardiac electrical activity., Aims: To compare electrical PR interval measured using non-invasive fetal electrocardiography (fECG) with mechanical atrioventricular (AV) interval using Doppler., Study Design and Subjects: Prospective study of 55 recordings made in 50 human fetuses. Those with structural heart defects, second degree or complete heart block were excluded., Outcome Measures: Mechanical AV interval was measured from the onset of mitral A wave to onset of aortic ejection. Electrical PR interval was measured from a coherent averaged signal obtained using non-invasive fECG recorded from the maternal abdomen. Wilcoxon signed rank test was used to compare both methods. Agreement between AV and PR intervals was assessed using linear regression and by Bland-Altman plots. Bland-Altman analysis assessed inter-observer and intra-observer variability., Results: There was no significant difference in the heart rates of the 55 paired traces measured consecutively using both methods (p<0.35). AV interval was longer than PR (median [range] 116 [96-169] vs. 102 [75-143] ms; p<0.001), with mean difference -16.47 ms (95% Confidence Interval -43.43, 10.44), reflecting the increased proportion of the cardiac cycle measured. Using fECG, PR inter-observer and intra-observer mean differences were 0.4 ms (CI -7.29, 8.09) and 0.7 ms (CI -3.22, 4.62) respectively. R values for inter and intra-observer studies were 0.95 and 0.99 respectively. Using Doppler methods, AV inter-observer and intra-observer mean differences were -2.69 ms, (CI -15.33, 9.95) and 0.92 ms, (CI -9.41, 11.26) respectively. R values for AV measurements were 0.93 for inter-observer and 0.96 for intra-observer variation., Conclusions: Non-invasive fECG is a robust tool to measure the PR interval with narrow limits of agreement.
- Published
- 2007
- Full Text
- View/download PDF
20. Prenatal diagnosis of absent right and persistent left superior vena cava.
- Author
-
Pasquini L, Belmar C, Seale A, and Gardiner HM
- Subjects
- Adult, Female, Humans, Infant, Newborn, Live Birth, Pregnancy, Twins, Dizygotic, Diseases in Twins diagnostic imaging, Echocardiography, Heart Defects, Congenital pathology, Ultrasonography, Prenatal methods, Vena Cava, Superior abnormalities
- Abstract
Objective: Persistence of left superior vena cava (LSVC) is a known variant of the systemic venous return. In the setting of an otherwise structurally normal heart, absence of the right superior vena cava (RSVC) but persistence of the LSVC is rare., Methods: We describe the prenatal findings of a fetus with absent right and persistent LSVC., Results: A dichorionic diamniotic twin pregnancy was referred to our centre with cardiac disproportion. Twin A had disproportion at four-chamber level, an absent right but persistent LSVC draining to an enlarged coronary sinus and a hypoplastic transverse aortic arch (<2 mm). Postnatal echocardiography of the asymptomatic baby confirmed the prenatal diagnosis, and serial echocardiograms demonstrated general hypoplasia of the aortic arch but no discrete coarctation (CoA). No intervention was required and the baby is thriving aged 10 months., Conclusion: Persistence of LSVC is a known variant of the systemic venous return. In the setting of an otherwise structurally normal heart, absence of the right but persistence of LSVC is rare.
- Published
- 2006
- Full Text
- View/download PDF
21. Total knee arthroplasty in patients 90 years of age and older.
- Author
-
Belmar CJ, Barth P, Lonner JH, and Lotke PA
- Subjects
- Aged, Aged, 80 and over, Follow-Up Studies, Humans, Pain surgery, Arthroplasty, Replacement, Knee adverse effects, Postoperative Complications epidemiology
- Abstract
With increasing longevity, more patients older than age 90 now are becoming candidates for total knee arthroplasty. This article reviews our experience with the perioperative morbidity and early outcomes in 12 patients older than age 90, undergoing 15 total knee surgeries. Postoperative Knee Society clinical and functional scores showed excellent outcomes, and the quality of life is enhanced. There were no significant surgical complications; however, there were several nonsurgical complications, including mental confusion (3), urinary retention (3), atrial fibrillation (2), atrial flutter (1), and gallstone retention and gastrointestinal bleed (1). Most of these complications stemmed directly from the preoperative medical condition. These are predictive and therefore may be recognized early and treated aggressively. Total knee surgery can be performed safely in patients older than 90 years old with excellent pain relief and enhanced quality of life. The surgeon should be aware of the patient's past medical history because this predisposes to postoperative morbidity.
- Published
- 1999
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.