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1.
Nucleic Acids Res ; 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39373482

RESUMO

The model organism Escherichia coli K-12 has one of the most extensively annotated genomes in terms of functional characterization, yet a significant number of genes, ∼35%, are still considered poorly characterized. Initially genes without known functional understanding were given 'y' gene names. However, due to inconsistency in changing 'y' names to non-'y' names over the years, gene name alone does not provide sufficient information as to the characterization level of genes. Attempts to characterize y-ome genes, i.e. those that lack experimental evidence for function, are ongoing, and recent categorization based on the level of experimental evidence has helped clarify those genes that are well characterized versus uncharacterized. EcoCyc, the most comprehensive, curated genome database for E. coli K-12 substr. MG1655, has updated this approach by expanding the categories to include Partially characterized genes using a set of computational rules that includes keywords, experimental evidence codes and Gene Ontology terms. Approximately half of the previously categorized y-ome genes are now categorized as Partially characterized, leaving 15.5% (738) as Uncharacterized genes in EcoCyc. This new categorization scheme is searchable in the EcoCyc database, will be updated as new experimental evidence is curated and provides important information for research decisions.

2.
Am J Perinatol ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38917867

RESUMO

OBJECTIVE: Maternal preconception diet influences pregnancy health and fetal outcomes. We examined the relationship between preconception fatty acid (FA) intake and uterine artery indices in mid-gestation in a large, heterogeneous cohort of nulliparous individuals. STUDY DESIGN: This is a secondary analysis of the nuMom2b (Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-be) study. Dietary ω-6 and ω-3 FA intake was assessed with food frequency questionnaires and uterine artery indices were obtained via Doppler studies in the second trimester. For our primary outcome of pulsatility index (PI) > 1.6, we compared proportions by each dichotomous FA exposure and tested differences with chi-square test. RESULTS: For PI > 1.6, odds ratio for the unfavorable FA quartile compared with remaining quartiles for the exposures were 0.96 to 1.25, p = 0.157 (ω-6 FA); 0.97 to 1.26, p = 0.124 (ω-3 FA); 0.87 to 1.14, p = 1.00 (ω-6:ω-3 FA ratio). CONCLUSION: No significant associations between self-reported maternal preconception ω-6 and ω-3 FA intake and uterine artery Doppler indices measured during the second trimester were observed. KEY POINTS: · Maternal diet impacts pregnancy health/fetal outcomes.. · ω-3 and ω-6 FA intake influences cardiovascular health.. · FA intake may affect blood flow to fetoplacental unit.. · Results are limited by inadequate adherence to dietary recommendations..

3.
Microbiology (Reading) ; 167(6)2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34170816

RESUMO

Marine plastic pollution is a growing concern worldwide and has the potential to impact marine life via leaching of chemicals, with zinc (Zn), a common plastic additive, observed at particularly high levels in plastic leachates in previous studies. At this time, however, little is known regarding how elevated Zn affects key groups of marine primary producers. Marine cyanobacterial genera Prochlorococcus and Synechococcus are considered to be some of the most abundant oxygenic phototrophs on earth, and together contribute significantly to oceanic primary productivity. Here we set out to investigate how two Prochlorococcus (MIT9312 and NATL2A) and two Synechococcus (CC9311 and WH8102) strains, representative of diverse ecological niches, respond to exposure to high Zn concentrations. The two genera showed differences in the timing and degree of growth and physiological responses to elevated Zn levels, with Prochlorococcus strains showing declines in their growth rate and photophysiology following exposure to 27 µg l-1 Zn, while Synechococcus CC9311 and WH8102 growth rates declined significantly on exposure to 52 and 152 µg l-1 Zn, respectively. Differences were also observed in each strain's capacity to maintain cell wall integrity on exposure to different levels of Zn. Our results indicate that excess Zn has the potential to pose a challenge to some marine picocyanobacteria and highlights the need to better understand how different marine Prochlorococcus and Synechococcus strains may respond to increasing concentrations of Zn in some marine regions.


Assuntos
Prochlorococcus/efeitos dos fármacos , Synechococcus/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Zinco/toxicidade , Prochlorococcus/crescimento & desenvolvimento , Água do Mar/análise , Água do Mar/microbiologia , Synechococcus/crescimento & desenvolvimento , Poluentes Químicos da Água/análise , Zinco/análise
4.
Biochem Soc Trans ; 49(6): 2465-2481, 2021 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-34882230

RESUMO

Marine cyanobacteria are key primary producers, contributing significantly to the microbial food web and biogeochemical cycles by releasing and importing many essential nutrients cycled through the environment. A subgroup of these, the picocyanobacteria (Synechococcus and Prochlorococcus), have colonised almost all marine ecosystems, covering a range of distinct light and temperature conditions, and nutrient profiles. The intra-clade diversities displayed by this monophyletic branch of cyanobacteria is indicative of their success across a broad range of environments. Part of this diversity is due to nutrient acquisition mechanisms, such as the use of high-affinity ATP-binding cassette (ABC) transporters to competitively acquire nutrients, particularly in oligotrophic (nutrient scarce) marine environments. The specificity of nutrient uptake in ABC transporters is primarily determined by the peripheral substrate-binding protein (SBP), a receptor protein that mediates ligand recognition and initiates translocation into the cell. The recent availability of large numbers of sequenced picocyanobacterial genomes indicates both Synechococcus and Prochlorococcus apportion >50% of their transport capacity to ABC transport systems. However, the low degree of sequence homology among the SBP family limits the reliability of functional assignments using sequence annotation and prediction tools. This review highlights the use of known SBP structural representatives for the uptake of key nutrient classes by cyanobacteria to compare with predicted SBP functionalities within sequenced marine picocyanobacteria genomes. This review shows the broad range of conserved biochemical functions of picocyanobacteria and the range of novel and hypothetical ABC transport systems that require further functional characterisation.


Assuntos
Proteínas de Transporte/metabolismo , Cianobactérias/metabolismo , Nutrientes/metabolismo , Água do Mar/microbiologia , Proteínas de Transporte/química , Metais/metabolismo , Nitrogênio/metabolismo , Fósforo/metabolismo , Conformação Proteica , Oligoelementos/metabolismo
5.
Wound Repair Regen ; 29(5): 830-842, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33956391

RESUMO

Microbial contamination of wounds is a significant problem that delays healing, particularly when bacterial biofilms are present. A novel combination of pectinic acid (PG) + caprylic acid (CAP) was previously found in vitro to be highly effective in eradicating various pathogens in biofilms with minimal cytotoxicity. In this study, a novel wound ointment was formulated with PG + CAP and first assessed in vitro using a well-established biofilm eradication model. In vitro, the PG + CAP ointment was shown to be efficacious in reducing the microbial biofilms. This ointment was then tested in vivo in two pilot porcine wound healing models, with and without Staphylococcus aureus microbial challenge. Ointments were applied to each wound daily, and healing by wound closure area measurement was assessed weekly over 4 weeks. After 4 weeks, pigs were sacrificed and wounds were scored for reepithelialization, inflammation, granulation tissue, and collagen deposition. We compared PG + CAP to hydroxyethylcellulose + glycerol ointment base (control) and MediHoney (comparator). In the porcine microbial challenge model, the novel antimicrobial PG + CAP wound ointment rapidly eradicated bacterial organisms embedded in wounds, was safe and well-tolerated, and was associated with enhanced healing compared to ointment base and MediHoney. Specifically, the cumulative histopathology, reepithelialization of epidermis, and mature granulation tissue in the wound bed was significantly better with PG + CAP than with control and MediHoney treatments. This ointment warrants further study as a non-antibiotic ointment for use in treating a wide array of infected wounds.


Assuntos
Anti-Infecciosos , Infecção dos Ferimentos , Animais , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Pomadas , Suínos , Cicatrização , Infecção dos Ferimentos/tratamento farmacológico
6.
Eur J Nutr ; 60(3): 1313-1326, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32671459

RESUMO

PURPOSE: Obesity and high-fat (HF) diet are associated with over activation of the endocannabinoid system (ECS). We have demonstrated that maternal HF diet induces early obesity and modulates cannabinoid signaling in visceral (VIS) and subcutaneous (SUB) white adipose tissue (WAT) in weanling rat offspring. We hypothesized that perinatal maternal HF diet would program the expression of ECS in adipose tissue in a long-term way in parallel to alterations in epigenetic markers and sex hormone signaling. METHODS: Progenitor female rats received control diet (C, 9% fat) or isocaloric high-fat diet (HF, 28% fat) for 8 weeks before mating, gestation, and lactation. All pups were weaned to C diet and they were euthanized at 180 days old. RESULTS: Maternal HF diet induced overweight and increased SUB WAT mass of male and female adult offspring. Maternal HF diet induced hypertrophy of VIS and SUB adipocytes only in female offspring associated with increased type 1 cannabinoid receptor protein (CB1) and mRNA (Cnr1) levels. These changes were associated with increased estrogen receptor α binding to Cnr1 promoter in SUB WAT of adult female offspring, which may contribute to higher expression of Cnr1. CONCLUSION: Increased CB1 signaling in adipose tissue might contribute to higher adiposity programmed by maternal HF diet because endocannabinoids stimulate the accumulation of fat in the adipose tissue. Our findings provide molecular insights into sex-specific targets for anti-obesity therapies based on the endocannabinoid system.


Assuntos
Tecido Adiposo Branco , Dieta Hiperlipídica , Tecido Adiposo/metabolismo , Tecido Adiposo Branco/metabolismo , Adiposidade , Animais , Dieta Hiperlipídica/efeitos adversos , Estrogênios , Feminino , Masculino , Fenômenos Fisiológicos da Nutrição Materna , Gravidez , Ratos , Receptores de Canabinoides/metabolismo
7.
Sensors (Basel) ; 21(6)2021 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-33805690

RESUMO

In the midst of the COVID-19 pandemic, Remote Patient Monitoring technologies are highly important for clinicians and researchers. These connected-health technologies enable monitoring of patients and facilitate remote clinical trial research while reducing the potential for the spread of the novel coronavirus. There is a growing requirement for monitoring of the full 24 h spectrum of behaviours with a single research-grade sensor. This research describes a free-living and supervised protocol comparison study of the Verisense inertial measurement unit to assess physical activity and sleep parameters and compares it with the Actiwatch 2 actigraph. Fifteen adults (11 males, 23.4 ± 3.4 years and 4 females, 29 ± 12.6 years) wore both monitors for 2 consecutive days and nights in the free-living study while twelve adults (11 males, 23.4 ± 3.4 years and 1 female, 22 ± 0 years) wore both monitors for the duration of a gym-based supervised protocol study. Agreement of physical activity epoch-by-epoch data with activity classification of sedentary, light and moderate-to-vigorous activity and sleep metrics were evaluated using Spearman's rank-order correlation coefficients and Bland-Altman plots. For all activity, Verisense showed high agreement for both free-living and supervised protocol of r = 0.85 and r = 0.78, respectively. For physical activity classification, Verisense showed high agreement of sedentary activity of r = 0.72 for free-living but low agreement of r = 0.36 for supervised protocol; low agreement of light activity of r = 0.42 for free-living and negligible agreement of r = -0.04 for supervised protocol; and moderate agreement of moderate-to-vigorous activity of r = 0.52 for free-living with low agreement of r = 0.49 for supervised protocol. For sleep metrics, Verisense showed moderate agreement for sleep time and total sleep time of r = 0.66 and 0.54, respectively, but demonstrated high agreement for determination of wake time of r = 0.83. Overall, our results showed moderate-high agreement of Verisense with Actiwatch 2 for assessing epoch-by-epoch physical activity and sleep, but a lack of agreement for activity classifications. Future validation work of Verisense for activity cut-point potentially holds promise for 24 h continuous remote patient monitoring.


Assuntos
Acelerometria/instrumentação , Actigrafia/instrumentação , Exercício Físico/fisiologia , Monitorização Ambulatorial/instrumentação , Sono/fisiologia , Telemedicina , Telemetria/normas , Adolescente , Adulto , COVID-19 , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Ambulatorial/normas , Pandemias , Reprodutibilidade dos Testes , SARS-CoV-2
8.
Telemed J E Health ; 27(6): 625-634, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33030985

RESUMO

Background: The authors draw upon their experience with a successful, enterprise-level, telemedicine program implementation to present a "How To" paradigm for other academic health centers that wish to rapidly deploy such a program in the setting of the COVID-19 pandemic. The advent of social distancing as essential for decreasing viral transmission has made it challenging to provide medical care. Telemedicine has the potential to medically undistance health care providers while maintaining the quality of care delivered and fulfilling the goal of social distancing. Methods: Rather than simply reporting enterprise telemedicine successes, the authors detail key telemedicine elements essential for rapid deployment of both an ambulatory and inpatient telemedicine solution. Such a deployment requires a multifaceted strategy: (1) determining the appropriateness of telemedicine use, (2) understanding the interface with the electronic health record, (3) knowing the equipment and resources needed, (4) developing a rapid rollout plan, (5) establishing a command center for post go-live support, (6) creating and disseminating reference materials and educational guides, (7) training clinicians, patients, and clinic schedulers, (8) considering billing and credentialing implications, (9) building a robust communications strategy, and (10) measuring key outcomes. Results: Initial results are reported, showing a telemedicine rate increase to 45.8% (58.6% video and telephone) in just the first week of rollout. Over a 5-month period, the enterprise has since conducted over 119,500 ambulatory telemedicine evaluations (a 1,000-fold rate increase from the pre-COVID-19 time period). Conclusion: This article is designed to offer a "How To" potential best practice approach for others wishing to quickly implement a telemedicine program during the COVID-19 pandemic.


Assuntos
COVID-19 , Telemedicina , Humanos , Pacientes Internados , Pandemias , SARS-CoV-2
9.
Am J Physiol Lung Cell Mol Physiol ; 315(5): L816-L833, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30211655

RESUMO

Preterm birth and mechanical ventilation (MV) frequently lead to bronchopulmonary dysplasia, the histopathological hallmark of which is alveolar simplification. How developmental immaturity and ongoing injury, repair, and remodeling impact completion of alveolar formation later in life is not known, in part because of lack of suitable animal models. We report a new model, using former-preterm lambs, to test the hypothesis that they will have persistent alveolar simplification later in life. Moderately preterm lambs (~85% gestation) were supported by MV for ~6 days before being transitioned from all respiratory support to become former-preterm lambs. Results are compared with term control lambs that were not ventilated, and between males (M) and females (F). Alveolar simplification was quantified morphometrically and stereologically at 2 mo (4 M, 4 F) or 5 mo (4 M, 6 F) corrected postnatal age (cPNA) compared with unventilated, age-matched term control lambs (4 M, 4 F per control group). These postnatal ages in sheep are equivalent to human postnatal ages of 1-2 yr and ~6 yr, respectively. Multivariable linear regression results showed that former-preterm lambs at 2 or 5 mo cPNA had significantly thicker distal airspace walls ( P < 0.001 and P < 0.009, respectively), lower volume density of secondary septa ( P < 0.007 and P < 0.001, respectively), and lower radial alveolar count ( P < 0.003 and P < 0.020, respectively) compared with term control lambs. Sex-specific differences were not detected. We conclude that moderate preterm birth and MV for ~6 days impedes completion of alveolarization in former-preterm lambs. This new model provides the opportunity to identify underlying pathogenic mechanisms that may reveal treatment approaches.


Assuntos
Displasia Broncopulmonar/patologia , Pulmão/patologia , Animais , Animais Recém-Nascidos , Feminino , Idade Gestacional , Masculino , Modelos Animais , Respiração Artificial/métodos , Ovinos
10.
South Med J ; 111(9): 544-548, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30180252

RESUMO

OBJECTIVES: To determine the effect of maternal age (MA) and paternal age (PA) on the risk of gestational hypertension, preeclampsia, and eclampsia in women who delivered on the Texas-Mexico border. METHODS: A cohort study using birth certificate data (singleton pregnancies, years 2005-2010) from El Paso County, Texas, was conducted. Six parental age-exposure categories were created with MA 20 to 34 years and PA younger than 35 years serving as the referent. A directed acyclic graph was created. Adjusted risk ratios for the composite outcome of gestational hypertension, preeclampsia, or eclampsia were calculated using Poisson regression. RESULTS: A total of 85,114 records were identified, with a majority of the mothers being of Hispanic ethnicity (89.2%). The incidence of the composite outcome ranged from 2.8% in the MA 20 to 34 years old and PA 35 years and older group to 4.4% in the MA younger than 20 years old and PA 35 years and older group. Compared to the MA 20 to 34 years old and PA younger than 35 years group, women in the MA 35 years and older and PA 35 years and older groups were more likely to experience the outcome (adjusted risk ratio 1.57, 95% confidence interval 1.39-1.77, P < 0.0001). CONCLUSIONS: Couples in which both parents are 35 years old and older should be counseled on the increased risk of gestational hypertension or preeclampsia/eclampsia.


Assuntos
Hipertensão Induzida pela Gravidez/etiologia , Idade Materna , Idade Paterna , Pré-Eclâmpsia/etiologia , Adulto , Feminino , Humanos , Hipertensão Induzida pela Gravidez/epidemiologia , Incidência , Masculino , Pré-Eclâmpsia/epidemiologia , Gravidez , Estudos Retrospectivos , Fatores de Risco , Texas/epidemiologia , Adulto Jovem
11.
BMC Bioinformatics ; 17(1): 528, 2016 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-27955641

RESUMO

BACKGROUND: The large-scale analysis of phenomic data (i.e., full phenotypic traits of an organism, such as shape, metabolic substrates, and growth conditions) in microbial bioinformatics has been hampered by the lack of tools to rapidly and accurately extract phenotypic data from existing legacy text in the field of microbiology. To quickly obtain knowledge on the distribution and evolution of microbial traits, an information extraction system needed to be developed to extract phenotypic characters from large numbers of taxonomic descriptions so they can be used as input to existing phylogenetic analysis software packages. RESULTS: We report the development and evaluation of Microbial Phenomics Information Extractor (MicroPIE, version 0.1.0). MicroPIE is a natural language processing application that uses a robust supervised classification algorithm (Support Vector Machine) to identify characters from sentences in prokaryotic taxonomic descriptions, followed by a combination of algorithms applying linguistic rules with groups of known terms to extract characters as well as character states. The input to MicroPIE is a set of taxonomic descriptions (clean text). The output is a taxon-by-character matrix-with taxa in the rows and a set of 42 pre-defined characters (e.g., optimum growth temperature) in the columns. The performance of MicroPIE was evaluated against a gold standard matrix and another student-made matrix. Results show that, compared to the gold standard, MicroPIE extracted 21 characters (50%) with a Relaxed F1 score > 0.80 and 16 characters (38%) with Relaxed F1 scores ranging between 0.50 and 0.80. Inclusion of a character prediction component (SVM) improved the overall performance of MicroPIE, notably the precision. Evaluated against the same gold standard, MicroPIE performed significantly better than the undergraduate students. CONCLUSION: MicroPIE is a promising new tool for the rapid and efficient extraction of phenotypic character information from prokaryotic taxonomic descriptions. However, further development, including incorporation of ontologies, will be necessary to improve the performance of the extraction for some character types.


Assuntos
Automação/métodos , Bactérias/classificação , Biologia Computacional/métodos , Células Procarióticas/classificação , Algoritmos , Automação/instrumentação , Bactérias/genética , Bactérias/metabolismo , Evolução Biológica , Biologia Computacional/instrumentação , Mineração de Dados/métodos , Armazenamento e Recuperação da Informação , Fenótipo , Células Procarióticas/metabolismo
12.
Pediatr Res ; 80(5): 719-728, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27429203

RESUMO

BACKGROUND: Preterm birth and respiratory support with invasive mechanical ventilation frequently leads to bronchopulmonary dysplasia (BPD). A hallmark feature of BPD is alveolar simplification. For our preterm lamb model of BPD, invasive mechanical ventilation is associated with postnatal feeding intolerance (reduced nutrition) and sedation. In contrast, preterm lambs managed by noninvasive support (NIS) have normal alveolar formation, appropriate postnatal nutrition, and require little sedation. We used the latter, positive-outcome group to discriminate the contribution of reduced nutrition vs. sedation on alveolar simplification. We hypothesized that, restricted nutrition, but not sedation with pentobarbital, contributes to impaired indices of alveolar formation in preterm lambs managed by NIS. METHODS: Preterm lambs managed by NIS for 21d were randomized into three groups: NIS control, NIS plus restricted nutrition, and NIS plus excess sedation with pentobarbital. We quantified morphological and biochemical indices of alveolar formation, as well as mesenchymal cell apoptosis and proliferation. RESULTS: Restricted nutrition impaired morphological and biochemical indices of alveolar formation, and reduced mesenchymal cell apoptosis and proliferation. Excess sedation with pentobarbital did not alter these indices, although mesenchymal cell apoptosis was less. CONCLUSION: Our results demonstrate that restricted nutrition, but not excess sedation, contributes to impaired alveolar formation during the evolution of BPD in chronically ventilated preterm lambs.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Displasia Broncopulmonar/patologia , Pentobarbital/administração & dosagem , Alvéolos Pulmonares/patologia , Animais , Animais Recém-Nascidos , Apoptose , Restrição Calórica , Proliferação de Células , Dieta , Feminino , Idade Gestacional , Hipnóticos e Sedativos/administração & dosagem , Hipnóticos e Sedativos/efeitos adversos , Pulmão/patologia , Masculino , Células-Tronco Mesenquimais/metabolismo , Estado Nutricional , Pentobarbital/efeitos adversos , Distribuição Aleatória , Respiração Artificial/efeitos adversos , Ovinos , Carneiro Doméstico , Fatores de Tempo
13.
Biochem Cell Biol ; 93(2): 119-27, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25493710

RESUMO

Perinatal insults, including intrauterine growth restriction, preterm birth, maternal exposure to toxins, or dietary deficiencies produce deviations in the epigenome of lung cells. Occurrence of perinatal insults often coincides with the final stages of lung development. The result of epigenome disruptions in response to perinatal insults during lung development may be long-term structural and functional impairment of the lung and development of lung disease. Understanding the contribution of epigenetic mechanisms to life-long lung disease following perinatal insults is the focus of the developmental origins of adult lung disease field. DNA methylation, histone modifications, and microRNA changes are all observed in various forms of lung disease. However, the perinatal contribution to such epigenetic mechanisms is poorly understood. Here we discuss the developmental origins of adult lung disease, the interplay between perinatal events, lung development and disease, and the role that epigenetic mechanisms play in connecting these events.


Assuntos
Metilação de DNA/genética , Epigênese Genética , Histonas/genética , Pneumopatias/embriologia , MicroRNAs/genética , Adulto , Animais , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Pulmão/embriologia , Masculino , Camundongos , Gravidez , Ratos , Ovinos
14.
Nature ; 458(7234): 69-72, 2009 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-19182781

RESUMO

Phosphorus is an obligate requirement for the growth of all organisms; major biochemical reservoirs of phosphorus in marine plankton include nucleic acids and phospholipids. However, eukaryotic phytoplankton and cyanobacteria (that is, 'phytoplankton' collectively) have the ability to decrease their cellular phosphorus content when phosphorus in their environment is scarce. The biochemical mechanisms that allow phytoplankton to limit their phosphorus demand and still maintain growth are largely unknown. Here we show that phytoplankton, in regions of oligotrophic ocean where phosphate is scarce, reduce their cellular phosphorus requirements by substituting non-phosphorus membrane lipids for phospholipids. In the Sargasso Sea, where phosphate concentrations were less than 10 nmol l-1, we found that only 1.3 +/- 0.6% of phosphate uptake was used for phospholipid synthesis; in contrast, in the South Pacific subtropical gyre, where phosphate was greater than 100 nmol l-1, plankton used 17 6% (ref. 6). Examination of the planktonic membrane lipids at these two locations showed that classes of sulphur- and nitrogen-containing membrane lipids, which are devoid of phosphorus, were more abundant in the Sargasso Sea than in the South Pacific. Furthermore, these non-phosphorus, 'substitute lipids' were dominant in phosphorus-limited cultures of all of the phytoplankton species we examined. In contrast, the marine heterotrophic bacteria we examined contained no substitute lipids and only phospholipids. Thus heterotrophic bacteria, which compete with phytoplankton for nutrients in oligotrophic regions like the Sargasso Sea, appear to have a biochemical phosphorus requirement that phytoplankton avoid by using substitute lipids. Our results suggest that phospholipid substitutions are fundamental biochemical mechanisms that allow phytoplankton to maintain growth in the face of phosphorus limitation.


Assuntos
Metabolismo dos Lipídeos , Lipídeos/química , Fósforo/deficiência , Fitoplâncton/metabolismo , Água do Mar/química , Carbono/análise , Lipídeos de Membrana/química , Nitrogênio/análise , Nitrogênio/metabolismo , Oceanos e Mares , Fosfatos/metabolismo , Fosfolipídeos/biossíntese , Fósforo/análise , Água do Mar/microbiologia , Synechococcus/química , Synechococcus/metabolismo
15.
Can Vet J ; 56(1): 35-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25565711

RESUMO

The use and efficacy of continuous rate infusion (CRI) of regular insulin intravenously for the treatment of feline diabetic ketoacidosis was retrospectively evaluated. The study focused on the rate of glucose decline, time to resolution of inappetence, time to long-term injectable insulin, and length of hospital stay. Review of medical records from 2009 to 2011 identified 10 cases that met the inclusion criteria. Six cats were existing diabetics, 3 of whom had recent insulin changes. Five cats had concurrent diseases. The mean time to long-term injectable insulin was 55 hours. The mean length of hospitalization was 3.8 days. Five cats survived to discharge. In 5 patients, an insulin CRI permitted a short hospital stay and transition to long-term injectable insulin. Many cats with diabetic ketosis or diabetic ketoacidosis are prior diabetics with concurrent disease and/or a history of recent insulin changes.


Évaluation rétrospective du taux d'infusion continu d'insuline régulière par intraveineuse pour la gestion de l'acidocétose diabétique féline. L'utilisation et l'efficacité de l'infusion à taux continu (ITC) de l'insuline régulière par intraveineuse pour le traitement de l'acidocétose ont été évaluées rétrospectivement. L'étude a porté sur le taux de diminution du glucose, le temps de résolution de l'inappétence, le délai jusqu'à l'insuline injectable à long terme et la durée du séjour à l'hôpital. L'examen des dossiers médicaux de 2009 à 2011 a identifié 10 cas qui satisfaisaient aux critères d'inclusion. Six chats étaient déjà diabétiques et 3 d'entre eux avaient présenté des changements récents de l'insuline. Cinq chats avaient des maladies concomitantes. Le délai moyen jusqu'à l'insuline injectable à long terme était de 55 heures. La durée moyenne de l'hospitalisation était de 3,8 jours. Cinq chats ont survécu au congé. Chez 5 patients, un ITC d'insuline a permis un court séjour à l'hôpital et une transition à l'insuline injectable à long terme. Plusieurs chats atteints d'acétose diabétique ou d'acidocétose diabétique étaient déjà diabétiques avec une maladie concomitante et/ou une anamnèse de changements récents de l'insuline.(Traduit par Isabelle Vallières).


Assuntos
Doenças do Gato/tratamento farmacológico , Cetoacidose Diabética/veterinária , Insulina/farmacologia , Animais , Glicemia/efeitos dos fármacos , Gatos , Cetoacidose Diabética/tratamento farmacológico , Esquema de Medicação , Feminino , Injeções Intravenosas , Insulina/administração & dosagem , Masculino , Estudos Retrospectivos
16.
Curr Top Microbiol Immunol ; 367: 75-98, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23224710

RESUMO

Certain vertebrates are capable of regenerating parts of the eye, including the lens. Depending on the species, two principal forms of in vivo lens regeneration have been described wherein the new lens arises from either the pigmented epithelium of the dorsal iris or the cornea epithelium. These forms of lens regeneration are triggered by retinal factors present in the eye. Studies have begun to illuminate the nature of the signals that support lens regeneration. This review describes evidence for the involvement of specific signaling pathways in lens regeneration, including the FGF, retinoic acid, TGF-beta, Wnt, and Hedgehog pathways.


Assuntos
Cristalino/fisiologia , Regeneração/fisiologia , Transdução de Sinais/fisiologia , Animais , Fatores de Crescimento de Fibroblastos/fisiologia , Proteínas Hedgehog/fisiologia , Fator de Crescimento Transformador beta/fisiologia , Tretinoína/fisiologia , Via de Sinalização Wnt/fisiologia
17.
Pediatr Res ; 76(1): 17-23, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24727947

RESUMO

BACKGROUND: Maternal tobacco smoke (MTS) predisposes human and rat offspring to visceral obesity in early adulthood. Glucocorticoid excess also causes visceral obesity. We hypothesized that in utero MTS would increase visceral adiposity and alter the glucocorticoid pathway in young adult rats. METHODS: We developed a novel model of in utero MTS exposure in pregnant rats by exposing them to cigarette smoke from E11.5 to term. Neonatal rats were cross-fostered to control dams and weaned to standard rat chow through young adulthood (postnatal day 60). RESULTS: We demonstrated increased visceral adiposity (193%)*, increased visceral adipose 11-ß hydroxysteroid dehydrogenase 1 mRNA (204%)*, increased serum corticosterone (147%)*, and no change in glucocorticoid receptor protein in adult male MTS rat offspring. Female rats exposed to MTS in utero demonstrated no change in visceral or subcutaneous adiposity, decreased serum corticosterone (60%)*, and decreased adipose glucocorticoid receptor protein (66%)*. *P < 0.05. CONCLUSION: We conclude that in utero MTS exposure increased visceral adiposity and altered in the glucocorticoid pathway in a sex-specific manner. We speculate that in utero MTS exposure programs adipose dysfunction in adult male rat offspring via alteration in the glucocorticoid pathway.


Assuntos
Adipócitos/efeitos dos fármacos , Corticosterona/sangue , Gordura Intra-Abdominal/efeitos dos fármacos , Nicotiana/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal/patologia , Fumar/efeitos adversos , 11-beta-Hidroxiesteroide Desidrogenases/metabolismo , Adipocinas/sangue , Adiposidade , Animais , Cotinina/sangue , Feminino , Glucocorticoides , Inflamação/patologia , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/sangue , Ratos , Receptores de Glucocorticoides/metabolismo , Fumaça/efeitos adversos , Fatores de Tempo
18.
Pediatr Res ; 76(5): 432-40, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25119340

RESUMO

BACKGROUND: Intrauterine growth restriction (IUGR) increases the risk of adult-onset hypercholesterolemia. High-fat diet (HFD) consumption potentiates IUGR-induced increased cholesterol. Cholesterol is converted to bile acids by Cyp7a1 in preparation for excretion. We hypothesized that IUGR rats fed a HFD will have increased cholesterol, decreased Cyp7a1 protein levels, and decreased bile acids compared to control rats fed a HFD. METHODS: At day 21, IUGR and control pups were placed on one of three diets: a regular chow or one of two HFDs containing 1% or 2% cholesterol. Cholesterol levels and hepatic Cyp7a1 protein levels were quantified a postnatal week 28. RESULTS: Both HFDs increased serum cholesterol levels in control rats, and HFD fed IUGR rats had further increased serum cholesterol up to 35-fold. Both HFDs increased hepatic cholesterol levels, and IUGR further increased hepatic cholesterol levels up to fivefold. IUGR decreased hepatic Cyp7a1 protein up to 75%, and hepatic bile acids up to 54%. CONCLUSION: IUGR increased cholesterol and bile acids and decreased Cyp7a1 protein in rats fed a HFD without changing food intake. These findings suggest that IUGR increases the vulnerability of HFD fed rats to hypercholesterolemia via decreased cholesterol conversion to bile acids.


Assuntos
Colesterol/sangue , Dieta Hiperlipídica , Retardo do Crescimento Fetal , Hipercolesterolemia/etiologia , Efeitos Tardios da Exposição Pré-Natal , Animais , Ácidos e Sais Biliares/metabolismo , Biomarcadores/sangue , Colesterol 7-alfa-Hidroxilase/metabolismo , Modelos Animais de Doenças , Ingestão de Alimentos , Ácidos Graxos/sangue , Feminino , Hipercolesterolemia/sangue , Hipercolesterolemia/enzimologia , Fígado/enzimologia , Masculino , Gravidez , Ratos Sprague-Dawley , Fatores de Tempo , Regulação para Cima , Aumento de Peso
19.
Prenat Diagn ; 34(2): 128-33, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24190763

RESUMO

OBJECTIVE: Despite standardization in care, heterogeneity in outcomes persists for infants with hypoplastic left heart syndrome (HLHS). One potential factor is in utero stressors. Uteroplacental insufficiency (UPI) induces systemic vascular and myocardial adaptations in the absence of structural heart disease. The effect of UPI in HLHS is unknown. METHODS: We retrospectively analyzed infants undergoing Norwood palliation for HLHS from 2007 to 2012. We compared the umbilical artery systolic to diastolic (SD) ratio to growth outcomes and postoperative right ventricular function. RESULTS: Forty three infants met our inclusion criteria. Fetuses without a declining SD ratio with advancing gestational age had asymmetric birth biometry, defined as birth weight minus head circumference z scores (-0.9 vs -0.05, p < 0.01). The SD ratio near the end of gestation negatively correlated with asymmetric birth biometry (R = -0.521, p < 0.01) and interstage growth (R = -0.49, p = 0.04). Males with higher SD ratios had a greater postoperative incidence of abnormal right ventricular function. CONCLUSIONS: A higher umbilical artery SD ratio was associated with asymmetric prenatal growth, poor weight gain, and decreased myocardial performance in infants with HLHS. Better understanding of UPI's effects on cardiovascular development and metabolism in HLHS will help identify new strategies for targeting morbidity in this high risk population.


Assuntos
Pressão Arterial/fisiologia , Desenvolvimento Fetal/fisiologia , Coração Fetal/diagnóstico por imagem , Feto/irrigação sanguínea , Síndrome do Coração Esquerdo Hipoplásico/diagnóstico por imagem , Insuficiência Placentária/diagnóstico por imagem , Artérias Umbilicais/diagnóstico por imagem , Adaptação Fisiológica , Estudos de Coortes , Diástole , Ecocardiografia Doppler , Feminino , Coração Fetal/fisiopatologia , Humanos , Síndrome do Coração Esquerdo Hipoplásico/fisiopatologia , Síndrome do Coração Esquerdo Hipoplásico/cirurgia , Recém-Nascido , Masculino , Procedimentos de Norwood , Circulação Placentária/fisiologia , Insuficiência Placentária/fisiopatologia , Gravidez , Estudos Retrospectivos , Sístole , Ultrassonografia Pré-Natal , Artérias Umbilicais/fisiopatologia
20.
Pediatr Cardiol ; 35(4): 616-21, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24154504

RESUMO

The risk of necrotizing enterocolitis (NEC) in association with congenital heart disease is highest in patients with hypoplastic left heart syndrome (HLHS). Within the HLHS population, however, risk factors for NEC remain debated. We hypothesized that some infants with HLHS have vascular changes that contribute to gut hypoperfusion independent of diastolic runoff and low cardiac output. We analyzed the abdominal aorta pulsatility index and right-ventricular function on routine preoperative and postoperative echocardiograms for all infants who underwent stage I palliation for HLHS from January 2007 to January 2012. The echocardiography findings and clinical course were compared between those with and those without an episode of NEC. Of the 61 cases reviewed, 11 (18 %) developed NEC during a mean follow-up of 3.8 ± 1.3 years. Those with NEC had a lower abdominal aorta pulsatility index compared with those without NEC both on stage I preoperative (3.38 ± 0.15 vs. 3.89 ± 0.09, p < 0.05) and postoperative echocardiograms (2.21 ± 0.28 vs. 3.05 ± 0.78, p = 0.01) despite similar ventricular function and operative risk. Abdominal aorta Doppler pulsations are lower in patients with HLHS whose clinical course is complicated by NEC. This finding suggests that the systemic vasculature in a subset of neonates with HLHS may be inherently abnormal. Further investigation is warranted to determine if this is secondary to structural changes in the mesenteric and/or systemic vasculature.


Assuntos
Aorta Abdominal/fisiopatologia , Enterocolite Necrosante/etiologia , Síndrome do Coração Esquerdo Hipoplásico/complicações , Fluxo Sanguíneo Regional/fisiologia , Aorta Abdominal/diagnóstico por imagem , Enterocolite Necrosante/epidemiologia , Enterocolite Necrosante/fisiopatologia , Feminino , Seguimentos , Humanos , Síndrome do Coração Esquerdo Hipoplásico/mortalidade , Síndrome do Coração Esquerdo Hipoplásico/fisiopatologia , Incidência , Recém-Nascido , Masculino , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Fatores de Tempo , Ultrassonografia Doppler Dupla , Utah/epidemiologia , Função Ventricular Direita/fisiologia
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