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1.
Nat Microbiol ; 7(7): 1001-1015, 2022 07.
Article in English | MEDLINE | ID: mdl-35668112

ABSTRACT

Beneficial microorganisms are used to stimulate the germination of seeds; however, their growth-promoting mechanisms remain largely unexplored. Bacillus subtilis is commonly found in association with different plant organs, providing protection against pathogens or stimulating plant growth. We report that application of B. subtilis to melon seeds results in genetic and physiological responses in seeds that alter the metabolic and developmental status in 5-d and 1-month-old plants upon germination. We analysed mutants in different components of the extracellular matrix of B. subtilis biofilms in interaction with seeds and found cooperation in bacterial colonization of seed storage tissues and growth promotion. Combining confocal microscopy with fluorogenic probes, we found that two specific components of the extracellular matrix, amyloid protein TasA and fengycin, differentially increased the concentrations of reactive oxygen species inside seeds. Further, using electron and fluorescence microscopy and metabolomics, we showed that both TasA and fengycin targeted the oil bodies in the seed endosperm, resulting in specific changes in lipid metabolism and accumulation of glutathione-related molecules. In turn, this results in two different plant growth developmental programmes: TasA and fengycin stimulate the development of radicles, and fengycin alone stimulate the growth of adult plants and resistance in the phylloplane to the fungus Botrytis cinerea. Understanding mechanisms of bacterial growth promotion will enable the design of bespoke growth promotion strains.


Subject(s)
Bacillus subtilis , Cucurbitaceae , Bacillus subtilis/metabolism , Cucurbitaceae/microbiology , Extracellular Polymeric Substance Matrix , Lipid Droplets , Seeds/microbiology
2.
Science ; 371(6527): 386-390, 2021 01 22.
Article in English | MEDLINE | ID: mdl-33479150

ABSTRACT

Convergent evolution provides insights into the selective drivers underlying evolutionary change. Snake venoms, with a direct genetic basis and clearly defined functional phenotype, provide a model system for exploring the repeated evolution of adaptations. While snakes use venom primarily for predation, and venom composition often reflects diet specificity, three lineages of cobras have independently evolved the ability to spit venom at adversaries. Using gene, protein, and functional analyses, we show that the three spitting lineages possess venoms characterized by an up-regulation of phospholipase A2 (PLA2) toxins, which potentiate the action of preexisting venom cytotoxins to activate mammalian sensory neurons and cause enhanced pain. These repeated independent changes provide a fascinating example of convergent evolution across multiple phenotypic levels driven by selection for defense.


Subject(s)
Elapid Venoms/enzymology , Elapidae/classification , Elapidae/genetics , Evolution, Molecular , Group IV Phospholipases A2/genetics , Pain , Sensory Receptor Cells/physiology , Adaptation, Biological/genetics , Animals , Elapid Venoms/genetics , Phylogeny , Sensory Receptor Cells/metabolism
3.
EBioMedicine ; 30: 303-316, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29463472

ABSTRACT

Classical activation of M1 macrophages with lipopolysaccharide (LPS) is associated with a metabolic switch from oxidative phosphorylation to glycolysis. However, the generalizability of such metabolic remodeling to other modes of M1 macrophage stimulation, e.g. type II interferons (IFNs) such as IFNγ, has remained unknown as has the functional significance of aerobic glycolysis during macrophage activation. Here we demonstrate that IFNγ induces a rapid activation of aerobic glycolysis followed by a reduction in oxidative phosphorylation in M1 macrophages. Elevated glycolytic flux sustains cell viability and inflammatory activity, while limiting reliance on mitochondrial oxidative metabolism. Adenosine triphosphate (ATP) distributed by aerobic glycolysis is critical for sustaining IFN-γ triggered JAK (Janus tyrosine kinase)-STAT-1 (Signal Transducer and Activator of Transcription 1) signaling with phosphorylation of the transcription factor STAT-1 as its signature trait. Inhibition of aerobic glycolysis not only blocks the M1 phenotype and pro-inflammatory cytokine/chemokine production in murine macrophages and also human monocytes/macrophages. These findings extend on the potential functional role of immuno-metabolism from LPS- to IFNγ-linked diseases such as atherosclerosis and autoimmune disease.


Subject(s)
Inflammation/metabolism , Inflammation/pathology , Interferon-gamma/pharmacology , Macrophages/metabolism , Macrophages/pathology , Adenosine Triphosphate/biosynthesis , Animals , Cell Differentiation/drug effects , Cell Survival/drug effects , Chemokines/metabolism , Citric Acid Cycle/drug effects , Deoxyglucose/pharmacology , Female , Galactose/metabolism , Glycolysis/drug effects , Humans , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Janus Kinases/metabolism , Lactic Acid/metabolism , Macrophage Activation/drug effects , Macrophages/drug effects , Metabolome/drug effects , Mice , Mitochondria/drug effects , Mitochondria/metabolism , Nitric Oxide/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Pyruvic Acid/metabolism , RAW 264.7 Cells , Reactive Oxygen Species/metabolism , STAT1 Transcription Factor/metabolism , Signal Transduction/drug effects
4.
J Card Fail ; 21(6): 460-9, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25911126

ABSTRACT

BACKGROUND: Heart failure (HF) is associated with ventricular dyssynchrony and energetic inefficiency, which can be alleviated by cardiac resynchronization therapy (CRT). The aim of this study was to determine the metabolomic signature in HF and its prognostic value regarding the response to CRT. METHODS AND RESULTS: This prospective study consisted of 24 patients undergoing CRT for advanced HF and 10 control patients who underwent catheter ablation for supraventricular arrhythmia but not CRT. Blood samples were collected before and 3 months after CRT. Metabolomic profiling of plasma samples was performed with the use of gas chromatography-mass spectrometry and nuclear magnetic resonance. The plasma metabolomic profile was altered in the HF patients, with a distinct panel of metabolites, including Krebs cycle and lipid, amino acid, and nucleotide metabolism. CRT improved the metabolomic profile. The succinate-glutamate ratio, an index of Krebs cycle activity, improved from 0.58 ± 0.13 to 2.84 ± 0.60 (P < .05). The glucose-palmitate ratio, an indicator of the balance between glycolytic and fatty acid metabolism, increased from 0.96 ± 0.05 to 1.54 ± 0.09 (P < .01). Compared with nonresponders to CRT, responders had a distinct baseline plasma metabolomic profile, including higher isoleucine, phenylalanine, leucine, glucose, and valine levels and lower glutamate levels at baseline (P < .05). CONCLUSIONS: CRT improves the plasma metabolomic profile of HF patients, indicating harmonization of myocardial energy substrate metabolism. CRT responders may have a favorable metabolomic profile as a potential biomarker for predicting CRT outcome.


Subject(s)
Cardiac Resynchronization Therapy/methods , Glucose/metabolism , Heart Failure , Isoleucine/metabolism , Phenylalanine/metabolism , Ventricular Dysfunction, Left/metabolism , Aged , Catheter Ablation/methods , Energy Metabolism/physiology , Female , Gas Chromatography-Mass Spectrometry/methods , Heart Failure/metabolism , Heart Failure/physiopathology , Heart Failure/therapy , Humans , Magnetic Resonance Spectroscopy/methods , Male , Metabolomics/methods , Middle Aged , Myocardium/metabolism , Predictive Value of Tests , Prognosis , Prospective Studies , Tachycardia, Supraventricular/surgery , Ventricular Dysfunction, Left/physiopathology , Ventricular Dysfunction, Left/therapy , Ventricular Remodeling/physiology
5.
Int J Artif Organs ; 30(12): 1098-108, 2007 Dec.
Article in English | MEDLINE | ID: mdl-18203072

ABSTRACT

BACKGROUND: Achieving optimal dry body weight in hemodialysis is challenging. Clinical assessment alone is inadequate, and methods such as bioimpedance monitoring may be impractical for every patient treatment. Continuous blood volume monitoring, blood pressure and heart rate variability inform clinical decision-making, but integrated use of multiple methodologies to achieve dry weight and understand patient factors has not yet been described. METHODS: Nineteen chronic hemodialysis patients underwent thrice-weekly treatments for two weeks. Baseline hydration status and target weight were determined by bioimpedance. During subsequent treatments, ultrafiltration was adjusted and relative blood volume, blood pressure and pulse were recorded non-invasively. Bioimpedance was repeated to assess hydration. Response of variables to progressive change in weight was assessed and selected patients underwent additional autonomic function testing. RESULTS: Four distinct hemodynamic patterns emerged. Profile A: 4 patients demonstrated overhydration at baseline. With decreasing target, pulse and blood pressure remained stable while blood volume and bioimpedance demonstrated achievement of dry weight. Profile B: 8 patients demonstrated overhydration at baseline. With decreasing target, blood pressure remained stable while pulse increased. Profile C: 5 patients were overhydrated, but as weight decreased, blood pressure became unstable and heart rate failed to compensate. Further testing confirmed autonomic dysfunction. Profile D: 2 patients were dehydrated, and with increasing target demonstrated stable pulse and pressure, while blood volume and bioimpedance revealed achievement of dry weight. CONCLUSIONS: Integrating existing non-invasive, continuous monitoring during hemodialysis enabled achievement of dry weight and identified distinct profiles of the patients, some with autonomic dysfunction. This strategy may contribute to achieving optimum dry weight while improving cardiovascular tolerability of hemodialysis.


Subject(s)
Blood Pressure , Blood Volume , Body Weight , Heart Rate , Kidney Failure, Chronic/physiopathology , Renal Dialysis , Electric Impedance , Female , Humans , Kidney Failure, Chronic/therapy , Male , Predictive Value of Tests , Prospective Studies
6.
Int J Artif Organs ; 28(5): 482-8, 2005 May.
Article in English | MEDLINE | ID: mdl-15883963

ABSTRACT

Sequential dialysis techniques (i.e pure ultrafiltration followed by dialysis) have been used in the past, due to their capability to remove large volumes of fluids without inducing hemodynamic instability. The disadvantages of inadequate efficiency and lack of technology lead to the decline of such methods. Hemofiltration (HF) and hemodiafiltration (HDF) are recently being utilized in a greater proportion thanks to on-line fluid preparation systems. Each process (HF and HDF) has its own benefits in the removal of small, medium and high-molecular weight substances and in hemodynamic stability. Sequential convective therapies (SCT) such as hemofiltration-hemodiafiltration in sequence (HF-HDF) may combine the benefits and eliminate the disadvantages of each method and should be studied in order to explore their potential application in modern dialysis. Furthermore they can be easily applied nowadays, due to the development of new sophisticated dialysis machines. In order to evaluate the feasibility, safety, efficiency and tolerance of different SCT methods we studied 3 schedules: SCT1: 1h pre-dilution HF followed by 3h of post-dilution HDF (in the HF mode we lost 25% of the total fluid that had to be removed). SCT2: 1h pre-dilution HF followed by 3h of post-dilution HDF (in the HF mode we lost 50% of the total fluid that had to be removed). SCT3: 2h pre-dilution HF followed by 2h of post-dilution HDF (in the HF mode we lost 50% of the total fluid that had to be removed). We studied 6 chronic hemodialysis patients using the same machine (AK200 ULTRA), with on-line fluid preparation system and the same type of dialyzer (Polyflux 210). SCT schedules were compared to on-line HF, on-line HDF and high flux dialysis performed with the same dialyzers. The treatments resulted safe, easy, feasible and well tolerated with an improved hemodynamic response to high volume convective therapies. Adequacy of treatment was satisfactory in all SCT schedules while middle molecular weight solute clearance and removal resulted higher in treatments with higher convective component. SCT might represent an interesting option for the future especially in patients with hemodynamic instability and requirements for interventions during treatment.


Subject(s)
Hemodiafiltration/methods , Hemofiltration/methods , Kidney Failure, Chronic/therapy , Online Systems , Blood Pressure/physiology , Blood Volume/physiology , Creatinine/metabolism , Cross-Over Studies , Feasibility Studies , Humans , Middle Aged , Phosphorus/metabolism , Prospective Studies , Urea/metabolism , beta 2-Microglobulin/metabolism
7.
Contrib Nephrol ; 149: 115-120, 2005.
Article in English | MEDLINE | ID: mdl-15876835

ABSTRACT

Sequential dialysis techniques (i.e. pure ultrafiltration followed by dialysis) have been used in the past, due to their capability to remove large volumes of fluids without inducing hemodynamic instability. The disadvantages of the inadequate dialysis and the lack of technology lead to the decline such methods. Hemofiltration (HF) and hemodiafiltration (HDF) are recently being utilized in a greater proportion thanks to the on line fluid preparation systems. Each process (HF and HDF) has its own benefits in the removal of small, medium and high-molecular weight substances and in the hemodynamic stability. Sequential hemofiltration/ hemodiafiltration (SHF/HDF), may combine the benefits and eliminate the disadvantages of each method. Furthermore they can be easily applied nowadays, due to the development of new high technological hemodialysis machines. In order to evaluate the feasibility and the effects of SHF/HDF we studied 7 chronic hemodialysis patients (6 months of treatment with SHF/HDF switched to 6 months of SHDF/HF), using the same machine (AK200 ULTRA), with on line fluid preparation system and the same type of dialyzer (Polyflux 210). The feasibility of such techniques (SHF/HDF or vice versa) resulted excellent. All sessions left the patients in a condition of well-being making fulltime work. No difference was observed between the different period of treatment, but a reduction in pre value was observed in calcium-phosphorous product, C-reactive protein and beta2-microglobulin, at the end of the sequential techniques. SHF/HDF therapy is a very promising technique. Further studies are needed to better explore the potential of such a therapeutic approach in the quality of life, the hemodialysis adequacy and the hemodynamic stability of our patients.


Subject(s)
Hemodiafiltration/methods , Hemofiltration/methods , Adult , Aged , C-Reactive Protein/metabolism , Calcium/blood , Cross-Over Studies , Equipment Design , Feasibility Studies , Hemodiafiltration/instrumentation , Hemofiltration/instrumentation , Humans , Middle Aged , Phosphorus/blood , Treatment Outcome , beta 2-Microglobulin/blood
8.
Rozhl Chir ; 83(3): 144-8, 2004 Mar.
Article in Czech | MEDLINE | ID: mdl-15216700

ABSTRACT

AIM: The aim of this work was to show current opinions on performing acute laparoscopic exploration in penetrating injuries of the abdomen and to assess the authors' own experience in performing the above operation in conditions of the regional hospital. METHODOLOGY: The authors present 17 patients treated between the years 1997-2002 for penetrating injuries of the abdomen or suspected for a penetrating injury. Acute laparotomy was performed in 11 cases, acute laparoscopy in 6 patients. The authors specify certain indications which lead to the acute laparoscopy, the method performed and its diagnostic value. RESULTS AND CONCLUSION: In the group observed, an intraabdominal injury was diagnosed in 41% of the patients, in 59% of cases findings were negative. When the intraabdominal injuries were assessed, the group of the acute laparotomies had 54% of negative findings, the group of the acute laparoscopies had 66.6% of negative findings. Laparoscopy decreased the total number of all negative laparotomies from 59% down to 35%. Diagnostic laparotomy fits to complement a spectrum of examination methods. Especially in equivocal cases, when a penetrating injury is suspected, it decreases the number of so called "necessary" non-therapeutic laparotomies to a minimum. It is most efficient, compared to other diagnostic methods, in verifying injuries of the peritoneum and diaphragm. However, acute laparoscopy should be always performed by an experienced surgeon. A therapeutic potential of the acute laparoscopy depend on proficiency of the operating surgeon and on the technical potential of each hospital. However, they, mostly, still remain restricted to caring for minor, isolated intraabdominal injuries.


Subject(s)
Abdominal Injuries/diagnosis , Abdominal Injuries/surgery , Wounds, Penetrating/diagnosis , Wounds, Penetrating/surgery , Algorithms , Humans , Laparotomy
9.
Rozhl Chir ; 82(1): 14-6, 2003 Jan.
Article in Czech | MEDLINE | ID: mdl-12687943

ABSTRACT

The authors describe the case-history of an uncommon traumatic haemoperitoneum which developed during sexual intercourse in a 49-year-old woman. She was admitted to the department of surgery of the Kromeríz Hospital on account of pain in the epigastrium. Previously the patient was free from complaints and collapsed on the way to the toilet. On admission she lacked sign of cardiopulmonary failure, on examination of the abdomen only deep painfulness on palpation in the epigastrium was found, on laboratory examination leukocytosis, the sonographic finding was negative. Two hours after admission signs of haemorrhagic shock developed, on abdomen symptoms of diffuse peritoneal irritation and on repeated sonographic examination accumulation of fluid in the abdominal cavity. The patient was subjected to an urgent operation with finding of rupture of a lienal aneurysm. Resection of the aneurysm and splenectomy were performed. During the subsequent course the patient was twice revised on account of a left-sided subphrenic abscess, now (six month after the first operation) she is free from complaints. The authors analyze incidence, etiology, clinical picture and treatment of aneurysm of the lienal artery. As to the clinical picture they emphasize the typical picture of two-stage rupture.


Subject(s)
Abdominal Injuries/complications , Aneurysm, Ruptured/complications , Hemoperitoneum/etiology , Splenic Artery , Aneurysm, Ruptured/diagnosis , Coitus , Female , Humans , Middle Aged
10.
Int J Artif Organs ; 23(11): 750-3, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11132019

ABSTRACT

The purpose of this study was to determine the changes in calcium and potassium content in the red blood cells (RBC) of uremic patients during a hemodialysis (HD) session and a 6/hrs CAPD exchange. RBC calcium and potassium were determined in 20 patients on HD in three blood samples collected at 0'-HD (pre-HD), 45'-HD and 240'-HD (end-HD), in 20 patients on CAPD, in two blood samples, collected at 0' time (pre-inflow) and 120', (solution in peritoneal cavity) during a 6/hrs exchange (4 exchanges / 24 h) and in 20 normal subjects. The mean value (+/-SD) of RBC calcium in controls was 15.6+/-3.75 micromol/L, in hemodialysed patients at 0'-HD, 45'-HD and 240'-HD 51.5+/-8.5, 70.4+/-12.5 and 51.1+/-10 micromol/L respectively and CAPD patients at time 0' and 120 of an exchange 53.6+/-23.4 and 70.6+/-9.2 respectively. These values show that RBC calcium in hemodialysed patients is generally significantly higher (p < 0.0001) than in controls. The value at 45'-HD is also significantly higher (p < 0.0001) than at 0' or 240'-HD. In CAPD patients, at 0' and 120' of a 6/hrs exchange, it is significantly higher (p < 0.0001) than in controls, as is the value at 120' (p < 0.001) in comparison to 0'. The mean value (+/-SD) of RBC potassium at the aforementioned time measurements were 95.9+/-3.34, 92.5+/-4.32 and 93.85+/-3.89 mmol/L respectively for patients on HD, 95+/-3.3 and 94.6+/-5.28 mmol/L respectively for patients on CAPD and 99.1+/-3.70 mmol/L in controls. These values show that RBC potassium of hemodialysed patients is significantly lower in comparison to that of controls (0'-HD: p < 0.01, 45'-HD and 240'-HD: p < 0.001); also the value at 45'-HD and 240'-HD is significantly lower (p < 0.001, p < 0.01 respectively) when compared to that at 0'-HD. In patients on CAPD, at 0' time and 120' during 6/hrs exchange, potassium is significant lower (p < 0.001) in comparison to that of controls. In conclusion, uremic patients present high erythrocyte calcium and low potassium with fluctuation during HD-sessions and CAPD 6/hrs exchange.


Subject(s)
Calcium/analysis , Erythrocytes/chemistry , Peritoneal Dialysis, Continuous Ambulatory/adverse effects , Potassium/analysis , Renal Dialysis/adverse effects , Uremia/therapy , Adult , Aged , Aged, 80 and over , Calcium/blood , Female , Humans , Male , Middle Aged , Peritoneal Dialysis, Continuous Ambulatory/methods , Potassium/blood , Probability , Reference Values , Renal Dialysis/methods , Uremia/blood
11.
Eur J Surg ; 162(4): 297-301, 1996 Apr.
Article in English | MEDLINE | ID: mdl-8739416

ABSTRACT

OBJECTIVE: To try and establish a consensus about the ideal secondary access for haemodialysis by assessing factors that affect the longevity of various access routes. DESIGN: Multicentre survey, by questionnaire. SETTING: General hospital, Athens. SUBJECTS: All 1516 patients in the Athens area receiving chronic haemodialysis. MAIN OUTCOME MEASURES: Longevity of present and any previous access routes (n = 2323). Data including type of access, age, sex and the existence of diabetes, hypertension, hyperlipidaemia, or other systematic diseases were recorded. RESULTS: Some 1220 (80%) of the patients were using autologous access, 1049 (69%) arteriovenous (AV) fistulas at wrist and 171 (11%) at elbow. Variables were analysed using Cox's proportional hazard model. Age and female sex were significantly associated with failure of autogenous access (p < 0.001) although not affecting synthetic grafts. Autogenous fistula at the elbow was the only secondary access that was less likely to fail than the initial (baseline) fistula at the wrist. Among the various grafts, straight arm grafts had the best prognosis and straight forearm grafts were the most likely to fail (p < 0.001). CONCLUSION: An AV fistula at the elbow should be considered the second best after the fistula at wrist, but is not always feasible. A synthetic graft is more likely to be needed in elderly patients and women, in whom an autogenous AV fistula is more likely to fail.


Subject(s)
Arteriovenous Shunt, Surgical , Blood Vessel Prosthesis , Polytetrafluoroethylene , Renal Dialysis , Age Factors , Brachiocephalic Trunk/surgery , Brachiocephalic Veins/surgery , Female , Graft Occlusion, Vascular/epidemiology , Greece , Humans , Male , Middle Aged , Proportional Hazards Models , Radial Artery/surgery , Sex Factors , Time Factors , Vascular Patency
12.
J Nurs Adm ; 21(3): 32-6, 1991 Mar.
Article in English | MEDLINE | ID: mdl-1900328

ABSTRACT

Documentation typically is an area that can be streamlined, thereby saving nursing time and money. The authors' nursing division created a combination intervention record and nursing progress notes form for a 24-hour period. The results yielded a savings of 90 minutes of RN time in a 24-hours period, a 36% reduction in charting time, and an annual cost savings of $437,000.


Subject(s)
Nursing Records/standards , Cost-Benefit Analysis , Documentation , Humans , Nursing Administration Research , Nursing Diagnosis , Nursing Process , Nursing Records/economics , Professional Staff Committees/organization & administration , Time Factors
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