[methyl-3H]Thymidine and [3H]leucine incorporation in Vibrio spp. grown in nutrient-limited continuous cultures

1994 ◽  
Vol 40 (5) ◽  
pp. 375-381 ◽  
Author(s):  
Richard A. Snyder ◽  
Richard D. Robarts ◽  
Douglas E. Caldwell
Keyword(s):  
Cell Volume ◽  
Bacterial Production ◽  
Conversion Factor ◽  
De Novo ◽  
Leucine Incorporation ◽  
Continuous Cultures ◽  
Average Cell ◽  
Conversion Factors ◽  
Significant Difference ◽  
Number Of Bacteria

Vibrio alginolyticus, Vibrio logei, Vibrio natriegens, and Vibrio neries were grown in nutrient-limited continuous cultures at generation times (TD) of 5–135 h on complex media with cell yields of 0.8–12 × 106 bacteria/mL. Average cell volume, as determined by image analysis of video fluorescence microscopy, decreased for V. logei and V. neries, did not change for V. alginolyticus, and increased for V. natriegens with increasing TD. The increase in cell volume observed for V. natriegens was due to the development of filamentous cells. Batch cultures were grown on media with 10 times the nutrient concentration of continuous cultures. Tritiated thymidine incorporation was measured using phenol–chloroform extractions; leucine incorporation was measured in trichloroacetic acid precipitates. At concentrations of exogenous thymidine high enough to inhibit de novo synthesis of thymidine, the number of bacteria produced per mole of thymidine incorporated did not vary with changing generation time, or between batch and continuous cultures examined in this study. However, the number of bacteria produced per mole of leucine incorporated decreased per unit production with increasing TD for all four vibrios. A significant difference in the bacterial production conversion factor (bacteria produced per mole of label incorporated) for thymidine was found for V. neries relative to the three other Vibrio species, but no significant differences were found between growth conditions within species. Corrections for biovolume differences between species and growth rates reduced variability in conversion factors, and also yielded a significantly different conversion factor for V. neries. Conversion factors for leucine incorporation spanned three orders of magnitude, from 1015 to 1018 bacteria/mol of leucine incorporated.Key words: leucine, thymidine, bacterial production, chemostats.

scholarly journals Empirical Leucine-to-Carbon Conversion Factors for Estimating Heterotrophic Bacterial Production: Seasonality and Predictability in a Temperate Coastal Ecosystem

2009 ◽  
Vol 75 (10) ◽  
pp. 3216-3221 ◽  
Author(s):  
Alejandra Calvo-D�az ◽  
Xos� Anxelu G. Mor�n
Keyword(s):  
Protein Synthesis ◽  
Bacterial Production ◽  
Heterotrophic Bacteria ◽  
Spatiotemporal Variability ◽  
Leucine Incorporation ◽  
Carbon Conversion ◽  
Conversion Factors ◽  
Production Studies ◽  
Favorable Conditions

ABSTRACT Leucine-to-carbon conversion factors (CFs) are needed for converting substrate incorporation into biomass production of heterotrophic bacteria. During 2006 we performed 20 dilution experiments for determining the spatiotemporal variability of empirical CFs in temperate Atlantic coastal waters. Values (0.49 to 1.92 kg C mol Leu−1) showed maxima in autumn to early winter and minima in summer. Spatially averaged CFs were significantly negatively correlated with in situ leucine incorporation rates (r = −0.91) and positively correlated with phosphate concentrations (r = 0.76). These relationships, together with a strong positive covariation between cell-specific leucine incorporation rates and carbon contents (r = 0.85), were interpreted as a strategy to maximize survival through protein synthesis and low growth rates under nutrient limitation (low CFs) until favorable conditions stimulate cell division relative to protein synthesis (high CFs). A multiple regression with in situ leucine incorporation rates and cellular carbon contents explained 96% of CF variance in our ecosystem, suggesting their potential prediction from more easily measurable routine variables. The use of the theoretical CF of 1.55 kg C mol Leu−1 would have resulted in a serious overestimation (73%) of annual bacterial production rates. Our results emphasize the need for considering the temporal scale in CFs for bacterial production studies.

scholarly journals Stacked volume conversion factor for geometric volume of Eucalyptus sp.

2019 ◽  
Vol 13 ◽  
pp. 46
Author(s):  
André Salgado De Andrade Sandim ◽  
Ariadna Coelho Mota ◽  
Mario Lima Dos Santos ◽  
Welton Dos Santos Barros ◽  
Beatriz Cordeiro Costa ◽  
...  
Keyword(s):  
Conversion Factor ◽  
Diameter Class ◽  
Wood Volume ◽  
Conversion Factors ◽  
Mean Values ◽  
Significant Difference ◽  
Clonal Plantation ◽  
Real Value ◽  
Different Diameters ◽  
Diameter Classes

Post-harvest, wood volume can be calculated with a stacking factor which can be influenced by diameter classes involved. Consequently, the following question arises: there is a difference between the volume conversion factor for stacked to geometric volume between piles of clonal plantation logs of different diameters classes? The hypothesis is: if smaller logs have a higher stacked to geometric volume conversion factor, between-log voids will be smaller and the overall stacks will therefore have lower volumes. Therefore, the objective of this study was to compare stacking and cubing factors in stacks of logs with different diameters for two Eucalyptus sp. clones. The study was conducted in Barra do Corda municipality, Maranhão State, Brazil. Timber was laid in piles of logs by diameter class, composed of logs of smaller (9-10.99 cm) and larger (11-13 cm) diameters. Stacking factor means for clone 1 were 1.88 for the larger diameter and 2.00 for the smaller diameter class, while for clone 2 mean values were 1.62 and 1.65, for stacks with larger and smaller diameter classes, respectively. For logs from the same clone there was no significant difference for the conversion factors between the stacks with the largest and smallest diameter. However, there was a significant difference in the conversion factors between the two clones, proving the hypothesis tested. Thus, for each genetic lineage, a proper stacking factor must be established so that the estimated volume comes close to the real value.

scholarly journals Inhibition of Kynurenine Metabolism and Its Effect in Mitochondrial Function in Hepatocellular Carcinoma

2020 ◽  
Vol 4 (Supplement_1) ◽  
pp. 124-125
Author(s):  
Raul Castro-Portuguez ◽  
Samuel Freitas ◽  
George Sutphin
Keyword(s):  
Hepatocellular Carcinoma ◽  
Mitochondrial Function ◽  
De Novo ◽  
Principal Component ◽  
Kynurenine Pathway ◽  
The Cancer Genome Atlas ◽  
Wilcoxon Test ◽  
Nad Synthesis ◽  
Significant Difference ◽  
Kynurenine Metabolism

Abstract Hepatocellular carcinoma (HCC) is the most prevalent cancer in the liver. The majority of ingested tryptophan is processed in the liver through the kynurenine pathway, the endpoint of which is de novo NAD+ biosynthesis. Dysregulation of tryptophan-kynurenine metabolism and NAD+ synthesis may promote mitochondrial malfunction, tumor reprogramming, and carcinogenesis. Using a publicly available gene expression dataset from liver hepatocellular carcinoma (LIHC) samples available through The Cancer Genome Atlas (TCGA; n = 371), we employed Principal Component Analysis (PCA), hierarchical clustering, gene-pattern expression profiling, and survival analysis to cluster patients and determine overall survival. Our analysis of genes encoding kynurenine pathway enzymes determined that patients with high QPRT expression had a poor prognosis with decreased median survival, with no effect on the maximum survival. There is a significant difference in the survival between patients with high QPRT expression relative to patients with high HAAO/AFMID expression (HR = 1.2, [95% CI 0.5-1.8] P = 0.0181, Gehan-Breslow-Wilcoxon Test). Patients with high QPRT expression have higher survival rates compared with low QPRT expression (HR = 1.4, [95% CI 0.9-2.2] P = 0.0344, Gehan-Breslow-Wilcoxon Test). To test the consequences of kynurenine-pathway inhibition in mitochondrial function and morphology we use 4-Cl-3HAA, an irreversible HAAO inhibitor, and observed a small increase in mitochondrial fragmentation in HepG2 cells after 24 hours of treatment. We conclude that kynurenine metabolism may be useful as a biomarker to predict patient prognosis among HCC patients. In ongoing work, we are testing QPRT inhibitors in cell culture as a potential adjuvant for chemotherapies.

Predictors Factors of Onset de Novo Heart failure after STEMI

2021 ◽  
Vol 28 (Supplement_1) ◽  
Author(s):  
S Abouradi ◽  
H Choukrani ◽  
A Maaroufi ◽  
A Drighil ◽  
R Habbal
Keyword(s):  
Heart Failure ◽  
De Novo ◽  
Microvascular Disease ◽  
Prior History ◽  
Killip Class ◽  
Funding Sources ◽  
Significant Difference ◽  
Primary Coronary Angioplasty ◽  
History Of ◽  
Predictor Factors

Abstract Funding Acknowledgements Type of funding sources: None. INTRODUCTION STEMI gets complicated very often by a heart failure (HF), which it is important to know associated factors. The aim of this study  was to determinate the predictor factors of onset of de novo HF after STEMI in patients with no prior history of heart failure recorded at baseline. METHODS A retrospective, descriptive study from 1 center in Morocco, including 210 patients hospitalized in a cardiology intensive care unit for STEMI from September 2019 to November 2020. The main outcomes were HF Killip class at hospital presentation and intra-hospital mortality. RESULTS The main age was 59.3 ± 7.02 and Sex ratio: 2, 86. The incidence of de novo HF at admission was higher in women (40, 4% vs. 29.5%, [OR 1, 61; 95%, [CI] 0, 83-3, 11). Forty-nine point eight percent were in Killip≥ 2. The method of early revascularization was Thrombolysis in 82, 3% compared to primary coronary angioplasty without significant difference in onset of the novo HF. There was no association of age, comorbidities, delay to hospital presentation and coronary involvement with incidence of onset of de novo HF.  Women had higher mortality than men with the novo HF (28, 6% vs. 20.5%; OR: 1, 55; 95%). CONCLUSION  Gender has appeared associated to onset of de novo HF after STEMI with a superiority of the female sex after controlling for others factors described in the literature. Anterior studies have related this to the increased prevalence of microvascular disease in women predisposing them to heart failure after STEMI.

scholarly journals Health-Related Quality of Life following Cytoreductive Radical Prostatectomy in Patients with de-novo Oligometastatic Prostate Cancer

Cancers ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 5636
Author(s):  
Michael Chaloupka ◽  
Lina Stoermer ◽  
Maria Apfelbeck ◽  
Alexander Buchner ◽  
Vera Wenter ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Prostate Cancer ◽  
Radical Prostatectomy ◽  
De Novo ◽  
Health Related Quality ◽  
Significant Difference ◽  
Related Quality ◽  
Health Related

(1) Background: local treatment of the primary tumor has become a valid therapeutic option in de-novo oligo-metastatic prostate cancer (PC). However, evidence regarding radical prostatectomy (RP) in this setting is still subpar, and the effect of cytoreductive RP on postoperative health-related quality of life (HRQOL) is still unclear. (2) Methods: for the current study, patients with de-novo oligo-metastatic PC (cM1-oligo), defined as ≤5 bone lesions in the preoperative staging, were included, and matched cohorts using the variables age, body-mass index (BMI), and pT-stage were generated. Patient-reported outcome measures (PROMS) were assessed pre- and postoperatively using the validated EORTC-QLQ-C30, IIEF-5, and ICIQ-SF questionnaires. The primary endpoint for univariate and multivariable analysis was good general HRQOL defined by previously validated cut-off values. (3) Results: in total, 1268 patients (n = 84 (7%) cM1-oligo) underwent RP between 2012 and 2020 at one tertiary care center. A matched cohort of 411 patients (n = 79 with oligo-metastatic bone disease (cM1-oligo) and n = 332 patients without clinical indication of metastatic disease (cM0)) was created. The median follow-up was 25mo. There was no significant difference in good general HRQOL rates between cM1-oligo-patients and cM0-patients before RP (45.6% vs. 55.2%, p = 0.186), and at time of follow-up (44% vs. 56%, p = 0.811). Global health status (GHS) worsened significantly in cM0-patients compared to baseline (−5, p = 0.001), whereas GHS did not change significantly in cM1-oligo-patients (+3.2, p = 0.381). In multivariate analysis stratified for good erectile function (IIEF5 > 18; OR 5.722, 95% CI 1.89–17.36, p = 0.002) and continence recovery (OR 1.671, 95% CI 1.03–2.70, p = 0.036), cM1-oligo was not an independent predictive feature for general HRQOL (OR 0.821, 95% CI 0.44–1.53, p = 0.536). (4) Conclusions: in this large contemporary retrospective analysis, we observed no significant difference in HRQOL in patients with the oligometastatic bone disease after cytoreductive radical prostatectomy, when compared to patients with localized disease at time of surgery.

scholarly journals De-novo multilayering in fibrovascular pigment epithelial detachment

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Manoj Soman ◽  
Jay U. Sheth ◽  
Asmita Indurkar ◽  
Padmanabhan Meleth ◽  
Unnikrishnan Nair
Keyword(s):  
De Novo ◽  
Median Number ◽  
Final Visit ◽  
Low Grade ◽  
Vascular Endothelial ◽  
Pigment Epithelial Detachment ◽  
Pigment Epithelial ◽  
Anti Vegf ◽  
Significant Difference ◽  
Endothelial Growth Factor

AbstractThis study describes the occurrence of multilayered pigment-epithelial detachment (MLPED) as a De-novo phenomenon (DN-MLPED) and compare the features with multi-layering secondary to chronic anti-vascular endothelial growth factor (anti-VEGF) therapy (s-MLPED). We did a retrospective evaluation of spectral-domain optical coherence tomography (SD-OCT) features, treatment-profile, and visual-acuity (VA) outcomes in eyes with MLPED. Out of 17 eyes with MLPED, 7 eyes had DN-MLPED and 10 eyes had s-MLPED. There was no significant difference in baseline and final VA between the groups. At the final visit, no significant visual improvement was noted in both the groups, although a possible trend towards an improvement was seen in DN-MLPED eyes while the s-MLPED demonstrated a declining trend (DN-MLPED—LogMAR-BCVA: Baseline = 0.79 [∼ 20/123] ± 0.91; Final = 0.76 [∼ 20/115] ± 0.73; p = 0.87; s-MLPED—LogMAR BCVA: Baseline = 0.43 [∼ 20/54] ± 0.68; Final = 0.94 [∼ 20/174] ± 0.71; p = 0.06). Moreover, after presentation, the median number of injections in DN-MLPED eyes were significantly lower compared to s-MLPED eyes (DN-MLPED:4; s-MLPED:12; p = 0.03) (Median follow-up: DN-MLPED = 26 months; s-MLPED = 54 months; p = 0.15). Subretinal hyperreflective-material (SHRM) deposition heralded the onset of multilayering and was seen to progress in all DN-PED eyes and 1/4 eyes of s-MLPED. To conclude, MLPED is a unique form of cicatrizing fibrovascular-PED which can evolve denovo too. Long-standing disease with intermittent or low-grade activity can potentially explain this unique phenomenon. With fewer anti-VEGF therapy, the de-novo MLPED eyes show more visual stability as compared to s-MLPED eyes.

scholarly journals CNNM2-Related Disorders: Phenotype and Its Severity Were Associated With the Mode of Inheritance

2021 ◽  
Vol 9 ◽  
Author(s):  
Han Zhang ◽  
Ye Wu ◽  
Yuwu Jiang
Keyword(s):  
De Novo ◽  
Serum Magnesium ◽  
Brain Magnetic Resonance Imaging ◽  
Functional Studies ◽  
Pathogenic Variants ◽  
Significant Difference ◽  
Domain Variations ◽  
Type 3

CNNM2 (Cystathionine-β-synthase-pair Domain Divalent Metal Cation Transport Mediator 2) pathogenic variants have been reported to cause hypomagnesemia, epilepsy, and intellectual disability/developmental delay (ID/DD). We identified two new cases with CNNM2 novel de novo pathogenic variants, c.814T>C and c.976G>C. They both presented with infantile-onset epilepsy with DD and hypomagnesemia refractory to magnesium supplementation. To date, 21 cases with CNNM2-related disorders have been reported. We combined all 23 cases to analyze the features of CNNM2-related disorders. The phenotypes can be classified into three types: type 1, autosomal dominant (AD) inherited simple hypomagnesemia; type 2, AD inherited hypomagnesemia with epilepsy and ID/DD; and type 3, autosomal recessive (AR) inherited hypomagnesemia with epilepsy and ID/DD. All five type 1 cases had no epilepsy or ID/DD; they all had hypomagnesemia, and three of them presented with symptoms secondary to hypomagnesemia. Fifteen type 2 patients could have ID/DD and seizures, which can be controlled with antiseizure medications (ASMs); their variations clustered in the DUF21 domain of CNNM2. All three type 3 patients had seizures from 1 to 6 days after birth; the seizures were refractory, and 1/3 had status epilepticus; ID/DD in these AR-inherited cases was more severe than that of AD-inherited cases; they all had abnormalities of brain magnetic resonance imaging (MRI). Except for one patient whose serum magnesium was the lower limit of normal, others had definite hypomagnesemia. Hypomagnesemia could be improved after magnesium supplement but could not return to the normal level. Variations in the CBS2 domain may be related to lower serum magnesium. However, there was no significant difference in the level of serum magnesium among the patients with three different types of CNNM2-related disorders. The severity of different phenotypes was therefore not explained by decreased serum magnesium. We expanded the spectrum of CNNM2 variants and classified the phenotypes of CNNM2-related disorders into three types. We found that DUF21 domain variations were most associated with CNNM2-related central nervous system phenotypes, whereas hypomagnesemia was more pronounced in patients with CBS2 domain variations, and AR-inherited CNNM2-related disorders had the most severe phenotype. These results provide important clues for further functional studies of CNNM2 and provide basic foundations for more accurate genetic counseling.

Sign in / Sign up

Export Citation Format

Share Document