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RNA Biology Feb 2017In vitro studies of translation provide critical mechanistic details, yet purification of large amounts of highly active eukaryotic ribosomes remains a challenge for...
In vitro studies of translation provide critical mechanistic details, yet purification of large amounts of highly active eukaryotic ribosomes remains a challenge for biochemists and structural biologists. Here, we present an optimized method for preparation of highly active yeast ribosomes that could easily be adapted for purification of ribosomes from other species. The use of a nitrogen mill for cell lysis coupled with chromatographic purification of the ribosomes results in 10-fold-increased yield and less variability compared with the traditional approach, which relies on sedimentation through sucrose cushions. We demonstrate that these ribosomes are equivalent to those made using the traditional method in a host of in vitro assays, and that utilization of this new method will consistently produce high yields of active yeast ribosomes.
Topics: Anion Exchange Resins; Chromatography, Ion Exchange; In Vitro Techniques; Potassium Chloride; Protein Biosynthesis; Ribosomes; Yeasts
PubMed: 27981882
DOI: 10.1080/15476286.2016.1270004 -
Anesthesiology Aug 1981Potassium and glucose are usually lacking in solutions employed for nerve conduction block. The significance of this for impulse conduction was studied in rabbit vagus...
Potassium and glucose are usually lacking in solutions employed for nerve conduction block. The significance of this for impulse conduction was studied in rabbit vagus nerve in vitro, incubated for 2 h Ringer's bicarbonate solution containing or lacking 5 mM glucose and 4 mM potassium chloride (n = 5 for each conditions). The c-fiber actin potential was recorded by periodic stimulation and the Na and K content of the desheathed nerve core was determined at the end of the incubation. In the presence of glucose, apparently normal conduction persisted for at least 2 h, even though the nerves incubated in potassium-free medium lost 20 per cent of their potassium. In the absence of glucose, reversible extinction of conduction was complete in 78 +/- 9 min when external potassium was present, and in 110 +/- 10 min when external potassium was absent. The data suggest that lack of glucose may reinforce C-fiber inexcitability during conduction block and that inclusion of a physiologic amount of potassium chloride in the solution may also be desirable.
Topics: Animals; Glucose; Nerve Block; Nerve Fibers; Neural Conduction; Potassium Chloride; Rabbits; Vagus Nerve
PubMed: 7258716
DOI: 10.1097/00000542-198108000-00013 -
Poultry Science Mar 1987Four experiments were conducted to study the impact of ambient temperature and relative humidity stress upon K excretion and the effects of KCl supplementation of...
Potassium balance of the 5 to 8-week-old broiler exposed to constant heat or cycling high temperature stress and the effects of supplemental potassium chloride on body weight gain and feed efficiency.
Four experiments were conducted to study the impact of ambient temperature and relative humidity stress upon K excretion and the effects of KCl supplementation of broilers exposed to chronic heat and cycling temperature stress. Potassium excretion, corrected for K intake and body weight, increased by 633% as ambient temperature was elevated from a constant 24 C to a constant 35 C. Feed (.73% K) and drinking water (0% K) were supplemented with KCl so effects of KCl on live weight gain and feed efficiency could be evaluated. In a previous study at thermoneutral temperature, no benefit of supplemental KCl was observed whereas in this study a dietary level of 1.5 to 2% K in the form of KCl improved gain under conditions of chronic high ambient temperature stress. This equals about 1.8 to 2.3 g K per chick daily or about .24 to .3% of the drinking water.
Topics: Animals; Body Weight; Chickens; Female; Hot Temperature; Male; Potassium; Potassium Chloride; Stress, Physiological
PubMed: 3601859
DOI: 10.3382/ps.0660487 -
Journal of Applied Microbiology Dec 2006To compare antifungal effects of cassia oil alone and in combination with potassium chloride (KCl) or sodium chloride (NaCl) against Alternaria alternata in vitro and in...
AIMS
To compare antifungal effects of cassia oil alone and in combination with potassium chloride (KCl) or sodium chloride (NaCl) against Alternaria alternata in vitro and in vivo.
METHODS AND RESULTS
The inhibitory effect of cassia oil alone, or in combination with KCl and NaCl were tested in vitro. The spore germination and germ tube elongation of the pathogen was evaluated in potato dextrose broth with light microscopy analysis. The inhibitory effect of cassia oil alone, or in combination with KCl and NaCl, was determined on cherry tomatoes in vivo. The cassia oil in combination with KCl and NaCl exhibited strong antifungal effect in vivo and in vitro.
CONCLUSIONS
The antifungal effect of cassia oil against Alt. alternata was enhanced significantly by combining with KCl and NaCl both in vitro and in vivo.
SIGNIFICANCE AND IMPACT OF THE STUDY
The combination of cassia oil and KCl or NaCl may enhance antifungal effect of cassia oil and reduce cost.
Topics: Alternaria; Cassia; Industrial Microbiology; Solanum lycopersicum; Mycoses; Oils, Volatile; Plant Diseases; Potassium Chloride; Sodium Chloride; Spores
PubMed: 17105562
DOI: 10.1111/j.1365-2672.2006.03024.x -
Journal of Structural Biology Oct 2018Mitochondria are central organelles for energy supply of cells and play an important role in maintenance of ionic balance. Consequently mitochondria are highly sensitive...
Mitochondria are central organelles for energy supply of cells and play an important role in maintenance of ionic balance. Consequently mitochondria are highly sensitive to any kind of stress to which they mainly response by disturbance of respiration, ROS production and release of cytochrome c into the cytoplasm. Many of the physiological and molecular stress reactions of mitochondria are well known, yet there is a lack of information on corresponding stress induced structural changes. 3-D visualization of high-pressure frozen cells by FIB-SEM tomography and TEM tomography as used for the present investigation provide an excellent tool for studying structure related mitochondrial stress reactions. In the present study it is shown that mitochondria in the unicellular fresh-water algal model system Micrasterias as well as in the closely related aquatic higher plant Lemna fuse to local networks as a consequence of exposure to ionic stress induced by addition of KCl, NaCl and CoCl. In dependence on concentration and duration of the treatment, fusion of mitochondria occurs either by formation of protuberances arising from the outer mitochondrial membrane, or by direct contact of the surface of elongated mitochondria. As our results show that respiration is maintained in both model systems during ionic stress and mitochondrial fusion, as well as formation of protuberances are reversible, we assume that mitochondrial fusion is a ubiquitous process that may help the cells to cope with stress. This may occur by interconnecting the respiratory chains of the individual mitochondria and by enhancing the buffer capacity against stress induced ionic imbalance.
Topics: Cobalt; Electron Microscope Tomography; Microscopy, Electron, Transmission; Mitochondria; Osmolar Concentration; Potassium Chloride; Sodium Chloride
PubMed: 29981486
DOI: 10.1016/j.jsb.2018.06.010 -
British Journal of Anaesthesia Aug 1983A double-blind investigation of the effect of adrenaline on conduction blockade was undertaken in six groups of rats (n = 12 or more) using a standardized injection of...
A double-blind investigation of the effect of adrenaline on conduction blockade was undertaken in six groups of rats (n = 12 or more) using a standardized injection of 0.4 ml of solution into the left infraorbital nerve. All six solutions contained lignocaine 0.25 g dl-1. In groups 1-3, the solutions were isotonic, in groups 4-6 the osmolarity was 0.6 isotonic. Solutions 1 and 4 contained potassium chloride 4 mmol litre-1 but no adrenaline; solutions 2 and 5 potassium chloride and adrenaline 5 micrograms ml-1 (1:200 000); solutions 3 and 6 adrenaline but no potassium chloride. The presence and duration of sensory blockade was determined from the reflex submandibular electromyographic response to periodic electrical stimulation of the homolateral and contralateral upper lips. In groups 1 and 4 (adrenaline absent) the mean durations of blockade (+/- SD) were 45 +/- 24 and 43 +/- 19 min. In groups 2, 3, 5 and 6 (adrenaline present) the durations of block averaged 97 +/- 4, 97 +/- 38, 105 +/- 21 and 92 +/- 16 min, respectively. Thus adrenaline approximately doubled the duration of blockade irrespective of osmolarity or potassium chloride concentration of the local anaesthetic solution (P less than 0.001).
Topics: Animals; Epinephrine; Lidocaine; Male; Nerve Block; Orbit; Osmolar Concentration; Potassium Chloride; Rats; Time Factors
PubMed: 6882611
DOI: 10.1093/bja/55.8.719 -
Heart (British Cardiac Society) Oct 1998
Review
Topics: Anti-Arrhythmia Agents; Combined Modality Therapy; Electric Countershock; Emergency Treatment; Humans; Lidocaine; Magnesium Sulfate; Potassium Chloride; Time Factors; Ventricular Fibrillation
PubMed: 9875125
DOI: 10.1136/hrt.80.4.408 -
Journal of Applied Physiology... May 2004Numerous studies have been devoted to the regeneration of the motor pathway toward a denervated muscle after nerve injury. However, the regeneration of sensory muscle...
Numerous studies have been devoted to the regeneration of the motor pathway toward a denervated muscle after nerve injury. However, the regeneration of sensory muscle endings after repair by self-anastomosis are little studied. In previous electrophysiological studies, our laboratory showed that the functional characteristics of tibialis anterior muscle afferents are differentially affected after injury and repair of the peroneal nerve with and without chronic electrostimulation. The present study focuses on the axonal regeneration of mechano- (fibers I and II) and metabosensitive (fibers III and IV) muscle afferents by evaluating the recovery of their response to different test agents after nerve injury and repair by self-anastomosis during 10 wk of treadmill running (LSR). Data were compared with control animals (C), animals with nerve lesion and suture (LS), and animals with lesion, suture, and chronic muscle rehabilitation by electrostimulation (LSE) with a biphasic current modulated in pulse duration and frequency, eliciting a pattern mimicking the activity delivered by the nerve to the muscle. Compared with the C group, results indicated that 1) muscle weight was smaller in LS and LSR groups, 2) the fatigue index was greater in the LS group and smaller in the LSE group, 3) metabosensibility remained altered in the LS and LSE groups, and 4) mechanosensitivity presented a large increase of the activation pattern in the LS and LSE groups. Our data indicated that chronic muscle electrostimulation partially favors the recovery of muscle properties (i.e., muscle weight and twitch response were close to the C group) and that rehabilitation by treadmill running also efficiently induced a better functional muscle afferent recovery (i.e., the discharge pattern was similar to the C group). The effectiveness of the chronic electromyostimulation and the treadmill exercise on afferent recovery is discussed with regard to parameters listed above.
Topics: Action Potentials; Animals; Axons; Electric Stimulation; Female; Injections; Lactic Acid; Motor Activity; Muscle Contraction; Muscle Fatigue; Muscle, Skeletal; Nerve Regeneration; Neuromuscular Junction; Neurons, Afferent; Organ Size; Peripheral Nerve Injuries; Potassium Chloride; Rats; Rats, Sprague-Dawley; Tendons; Vibration; Wound Healing; Wounds and Injuries
PubMed: 14634028
DOI: 10.1152/japplphysiol.00775.2003 -
Annals of Epidemiology Mar 1995We conducted a randomized, double-blind, placebo-controlled trial of oral potassium chloride supplementation (60 mmol/d) in 353 men and women with an initial average... (Clinical Trial)
Clinical Trial Randomized Controlled Trial
The effect of potassium supplementation in persons with a high-normal blood pressure. Results from phase I of the Trials of Hypertension Prevention (TOHP). Trials of Hypertension Prevention (TOHP) Collaborative Research Group.
We conducted a randomized, double-blind, placebo-controlled trial of oral potassium chloride supplementation (60 mmol/d) in 353 men and women with an initial average diastolic blood pressure between 80 and 89 mm Hg. In the active (n = 178) compared to the placebo (n = 175) treatment group, the urinary potassium level was significantly (p < 0.001) increased by an average of 44.0 and 42.3 mmol/24 h following 3 and 6 months of therapy, respectively. Compared to placebo, active treatment was associated with a small (mean = 1.8 mm Hg) but significant (p = 0.04) reduction in diastolic blood pressure following 3 months of therapy. Following 6 months, however, this apparent treatment effect had virtually disappeared (mean reduction in diastolic blood pressure = 0.3 mm Hg). There was no significant effect of potassium supplementation on systolic blood pressure at either follow-up visit. There was a significant, independent, dose-response relationship between change in both 24-hour urinary potassium excretion and urinary sodium-potassium ratio and the corresponding change in diastolic blood pressure (-1.49 mm Hg for the highest versus the lowest quartile of change in urinary potassium excretion.
Topics: Administration, Oral; Adult; Blood Pressure; Dose-Response Relationship, Drug; Double-Blind Method; Female; Humans; Hypertension; Male; Middle Aged; Nutritional Physiological Phenomena; Potassium Chloride; Prognosis
PubMed: 7795836
DOI: 10.1016/1047-2797(94)00053-v -
American Journal of Obstetrics and... Jul 1994Our goal was to develop the most comprehensive database possible to counsel patients about selective termination for fetal abnormalities, because no one center has...
OBJECTIVE
Our goal was to develop the most comprehensive database possible to counsel patients about selective termination for fetal abnormalities, because no one center has sufficient data to assess much more than crude loss rates.
STUDY DESIGN
A total of 183 completed cases of selective termination from 9 centers in 4 countries were combined (169 twins, 11 triplets, 3 quadruplets). Variables included indications, methods, (potassium chloride, exsanguination, air embolus), gestational age at procedure, pregnancies lost (< or = 24 weeks), gestational age at delivery, and neonatal outcome.
RESULTS
Indications for selective termination were 96 chromosomal, 76 structural, and 11 mendelian. Selective termination was technically successful in 100% of cases. In 23 of 183 (12.6%) miscarriage occurred before 24 weeks; 2 of 37 (5.4%) occurred when the procedure done at < or = 16 weeks and 21 of 146 (14.4%) when it was done thereafter. Air embolization had a higher loss rate: 10 of 24 (41.7%) compared with 13 of 156 (8.3%) by potassium chloride (chi 2 = 117, p < 0.0001). Three cases of selective termination performed in monochorionic pregnancies all resulted in pregnancy loss. Among 183 potentially viable deliveries, 7 occurred before 28 weeks, 19 at 29 to 32 weeks, 41 at 33 to 36 weeks, and 93 at > or = 37 weeks. Gestational age at delivery was not influenced by the technique used or the indication but was negatively correlated with gestational age at the time of selective termination. No coagulopathy or ischemic damage was observed in survivors. There was no maternal morbidity.
CONCLUSIONS
(1) Selective termination in experienced hands for a dizygotic abnormal twin is safe and effective when done with potassium chloride. A total of 83.8% of viable deliveries occurred after 33 weeks and only 4.3% at 25 to 28 weeks. (2) Gestational age at the procedure correlated positively with loss rate and inversely with gestational age at delivery; this emphasizes the need for early diagnosis in multifetal pregnancies. (3) Coagulopathy tests are probably unnecessary.
Topics: Abortion, Therapeutic; Chromosome Aberrations; Chromosome Disorders; Embolism, Air; Female; Fetal Diseases; Fetus; Humans; Potassium Chloride; Pregnancy; Pregnancy Outcome; Pregnancy Trimester, Second; Pregnancy, Multiple
PubMed: 8030739
DOI: 10.1016/s0002-9378(94)70083-4