Lipid Biosynthesis in Peroxisomes a

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74665/1/j.1749-6632.1996.tb18613.x.pd

Quantification, characterization and fatty acid composition of lysophosphatidic acid in different rat tissues

The amount and composition of lysophosphatidate present in different rat tissues have been estimated by an internal standard method in which a synthetic unnatural isomer (1‐heptadecanoyl‐rac‐glycerol‐3‐phosphate) was added to the total lipid extracts, and the fatty acid composition of purified lysophosphatidate was determined. Lipids from tissues were extracted under acidic conditions, and the lysophosphatidate was purified by solvent partitions followed by thin‐layer chromatography in multiple solvent systems. The purified lipid was shown to be 1‐acyl‐sn‐glycerol‐3‐phosphate by chromatographic and chemical analysis, by its resistance to hydrolysis when treated with phospholipase A2 and also by its complete conversion to 1‐acyl‐sn‐glycerol when treated with alkaline phosphatase. The fatty acid consituents of this lipid were determined by gas‐liquid chromatography of the derived methyl esters. The concentrations (nmol/g of tissue) of lysophosphatidate in various tissues were: 86.2±4.2 in brain, 60.3±6.3 in liver, 46.4±6.5 in kidney, 30.6±5.0 in testis, 22.3 in heart and 19.3 in lung. Mostly (80%) saturated fatty acids were found to be present in this lyso lipid. A significantly high level of stearic acid was present in this lipid from all the tissues (50–60% in liver, kidney, brain and testis, and about 40% in heart and lung) compared to plamitic acid (10–15% in liver, kidney and brain and 25–30% in testis, heart and lung). The fatty acid compositions of phosphatidic acid, the putative product of lysophosphatidate acylation, from different tissues were also determined and palmitate was found to be the major saturated fatty acid. These results suggest that tissue lysophosphatidic acid is not only formed byde novo biosynthesis but is also generated via the breakdown of phospholipids such as phosphoinositides.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141048/1/lipd0329.pd

Elektroencefalografske, elektrokardigrafske i spirometrijske promjene u koza uzrokovane propofolom

The effects of Propofol-induced electroencephalographic, electrocardiographic and spirometric changes were studied at a lower dose rate (0.4 mg/kg body mass, intravenously) and at higher dose rate (0.5 mg/kg body mass, intravenously) in four apparently healthy goats 10 to 14 months old, weighing 9 to 12 kg. Electroencephalographic results showed that anesthesia was induced with a change of distorted β wave patterns to α waves within one minute. The α wave patterns continued for 5 to 6 minutes at the lower dose (0.4 mg/kg body mass) while they persisted for 12 to 13 minutes at the higher dose (0.5 mg/kg body mass). At the lower dose, recovery was predictable after 5 minutes on reversal of the EEG pattern from α to β waves, whereas at the higher dose α wave patterns continued for 15 minutes. The occurrence of the righting reflfl ex was noticed after the disappearance of α waves. The heart rate increased with both the dose rates within the fifi rst 5 minutes and decreased after 10 and 15 minutes of induction. Inverted T waves were found in two goats at the lower dose while at the higher dose it was found to be inverted in three of the four goats. One of the goats inducted with the higher dose showed tachycardia, with ectopic beats from the 5th to 7th minute post induction. On average, apnea was noticed for the fifi rst 30 seconds at the lower dose and for 42 seconds at the higher dose. One of the animals receiving the higher dose showed apnea for 314 seconds. This goat was given artififi cial respiration after 106 seconds and then again after 296 seconds to resuscitate it. The animal showed severe respiratory distress with abdominal respiration during the fifi rst few seconds. The tidal volume did not return to normal until 15 minutes after induction. This indicates that Propofol has a respiratory depressant activity in goats and positive pressure ventilation must be provided. It does not induce analgesia and should be accompanied by analgesics .Istraživane su elektroencefalografske, elektrokardiografske i spirometrijske promjene uzrokovane propofolom u četiri zdrave koze u dobi od 10 do 14 mjeseci, mase od 9 do 12 kg. Propofol im je bio primijenjen intravenski u malim (0,4 mg/kg tjelesne mase) i većim (0,5 mg/kg tjelesne mase) dozama. Rezultati elektroencefalografi je pokazali su da se pri izazvanoj anesteziji obrazac β vala promijenio u α valove u tijeku jedne minute. Obrasci α vala nastavili su se tijekom 5 do 6 minuta kod primjene male doze (0,4 mg/kg tjelesne mase) dok su kod primjene veće doze (0,5 mg/kg tjelesne mase) trajali 12 do 13 minuta. Kod primjene manje doze oporavak se mogao očekivati nakon pet minuta s povratkom EEG obrasca s α na β val, dok je kod većih doza α val trajao do 15 minuta. Pojava refleksa dizanja bila je zapažena nakon nestanka α valova. Učestalost srčanih otkucaja povećala se kod primjene obiju doza tijekom prvih pet minuta, a smanjila se nakon 10 i 15 minuta. Negativan T val bio je ustanovljen u dvije koze kod primjene manje doze, dok je kod primjene veće doze on bio ustanovljen u tri koze. Jedna koza koja je dobila veću dozu pokazivala je tahikardiju s ektopičnim otkucajima od pete do sedme minute nakon indukcije. Apneja se prosječno javljala tijekom prvih 30 sekundi kod primjene manje doze, a tijekom 42 sekunde kod primjene veće doze. U jedne koze apneja je pri primjeni veće doze bila zabilježena tijekom 314 sekundi. Toj je kozi za buđenje dano umjetno disanje nakon 106 sekundi te ponovljeno nakon 296 sekundi. Životinje su pokazivale težak dišni poremećaj s trbušnim disanjem u tijeku prvih nekoliko sekundi. Vrijednosti su se vratile na normalu nakon 15 minuta. Rezultati pokazuju da propofol smanjuje dišnu aktivnost u koza te je nužno primijeniti ventilaciju s pozitivnim tlakom. On ne dovodi do gubitka osjeta boli te treba primijeniti analgetike

Dietary ether lipid incorporation into tissue plasmalogens of humans and rodents

Chronic feeding of 1‐O‐octadecyl‐sn‐glycerol (batyl alcohol) to patients suffering from congenital deficiency in tissue ether glycerolipids showed an increase in the plasmalogens content of their erythrocytes. However, nothing is known about the ether lipid content of other tissues in these patients. Feeding 1‐O‐heptadecyl‐sn‐glycerol to young rats showed that this uncommon ether lipid was incorporated to a high extent into the plasmalogens of all tissues except brain. Comparative studies with other precursors, such as 3‐O‐heptadecyl‐sn‐glycerol, heptadecanol and heptadecanoic acid, indicated a stereospecific incorporation of the dietary 1‐O‐alkyl‐sn‐glycerols into tissue plasmalogens without cleavage of the ether bond. Dietary ether lipids were also shown to be transferred from mothers to suckling rats, but not from pregnant rats to fetuses. The implication of these results to possible dietary ether lipid therapy for patients suffering from peroxisomal disorders is discussed.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141558/1/lipd0401.pd

Eleketroencefalografski pokazatelji za vrijeme anestezije propofolom i ksilazin-ketaminom u koza

The use of intravenous anaesthesia for short term surgical procedures in animal husbandry practices is increasing. However, information on the quality of an anaesthetic regime in goats has remained inadequate. Therefore, electroencephalographic studies were conducted on twelve apparently healthy adult female Barbari crossbred goats, aged 2 to 4 years, to assess the anaesthetic quality of a propofol and xylazine-ketamine combination. Quantitative analysis of EEG parameters [Total power, Median Frequency, Spectral Edge Frequency 90 (SEF-90) and Relative Power (RP) of different frequency bands delta (δ), theta (θ), alpha (α) and beta (β)] were assessed pre-experimentally (control), and at one, five, 10, 30 min, one hr, and two hr after intravenous propofol (4 mg/kg) and xylazine (0.05 mg/kg)-ketamine (4 mg/kg) administration. After propofol and xylazine-ketamine administration total power, RP-δ and θ increased significantly (P<0.05) while SEF 90, MF, RP-α and RP-β decreased. Most of the EEG changes were adequately depicted in vertex and parietal channels. Spectral analysis of EEG tracings suggested that propofol produced minimum anaesthetic stress and is a safer and better choice for short term anaesthesia in goats.U stočarskoj praksi se za kratkotrajne kirurške zahvate sve više primjenjuje intravenska anestezija. Nedostaju međutim podaci na temelju kojih bi se ustanovila kvaliteta anestezijskog protokola u koza. Kako bi se procijenila kvaliteta kombinacije anestetika propofola i ksilazin-ketamina, provedena je analiza elektoencefalografskih pokazatelja u 12 zdravih odraslih koza. Koze su bili križanci barbari pasmine u dobi od 2 do 4 godine. Kvantitativna analiza EEG pokazatelja (total power, median frequency, SEF-90, relative power delta-δ, theta-θ, alfa-α i beta-β frekvencijskih pojaseva) procijenjeni su prije pokusa (kontrolna skupina), te 1, 5, 10, 30 minuta, jedan sat i dva sata nakon intravenske primjene propofola (4 mg/kg) i ksilazin (0,05 mg/kg)-ketamina (4 mg/kg). Nakon primjene propofola i ksilazin-ketamina total power, te relative power-δ i relative power-θ znakovito su porasli (P < 0,05), dok su se SEF 90, median frequency, relative power-α i relative power-β snizili. Većina EEG promjena odgovarajuće je prikazana u verteksu i parijetalnim kanalima. Spektralna analiza EEG-a upućuje na to da propofol u anestezijskom protokolu uzrokuje minimalan stres te je, u usporedbi sa ksilazin-ketaminom, za kratkotrajnu anesteziju koza sigurniji i bolji izbor

Inhibition of pathogenic bacterial biofilms on PDMS based implants by L. acidophilus derived biosurfactant

Abstract Background Lactobacillus spp. predominantly shows its presence as a normal mucosal flora of the mouth and intestine. Therefore, the objective of our research is to investigate the in-vitro conditions for the prospective of medically valuable biosurfactants (BSs) derived from Lactobacillus spp. Biosurfactant (BS) obtained from Lactobacillus spp. exhibit antibiofilm and antiadhesive activity against broad range of microbes. In the present study we investigated the production, purification and properties of key components of the cell-associated-biosurfactant (CABS) from Lactobacillus acidophilus NCIM 2903. Results Extracted, purified, freeze-dried CABS shows reduction in surface tension (SFT) of phosphate buffer saline (PBS @pH 7.0) from 71 to 26 mN/m and had a critical micelle concentration (CMC) of 23.6 mg/mL. The CABS showed reduction in interfacial tension (IFT) against various hydrocarbons and had effective spreading capability as reflected through the decrease in contact angle (CA) on different surfaces (polydimethylsiloxane - PDMS, Teflon tape, glass surface, polystyrene film and OHP sheet). The anionic nature of CABS displayed stability at different pH and temperatures and formed stable emulsions. Thin layer chromatography (TLC) and Fourier transform infrared spectroscopy (FTIR) revealed CABS as glycolipoprotein type. The Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis (SDS-PAGE) showed presence of multiple bands in a molecular range of 14.4 to 60 kDa, with prominent bands of 45 kDa. The CABS has significant antiadhesion and antibiofilm activity against tested bacterial strains. Conclusion The current challenging situation is to develop methods or search for the molecules that will prevent the formations of biofilm on medical bioimplants of PDMS based materials. These findings are supportive for the use of Lactobacilli derived BS as potential antiadhesive agent on various surfaces of biomedical devices

Lactobacillus acidophilus Derived Biosurfactant as a Biofilm Inhibitor: A Promising Investigation Using Microfluidic Approach

Background: Biomedical devices and implants are adversely affected by biofilm-associated infections that pose serious public health issues. Biosurfactants (BSs) can combat pathogenic biofilms through their antimicrobial, antibiofilm and antiadhesive capabilities. The objective of our research was to produce biosurfactant (BS) from Lactobacillus acidophilus NCIM 2903 and investigate its antibiofilm, antiadhesive potential using microfluidics strategies by mimicking the micro-environment of biofilm. Methods: Antibiofilm and antiadhesive potential was effectively evaluated using different methods like microfluidics assay, catheter assay, polydimethlysiloxane (PDMS) disc assay. Along with this chemical and physical characteristics of BS were also evaluated. Results: Cell free biosurfactant (CFBS) obtained was found to be effective against biofilm which was validated through the microfluidic (MF) or Lab on Chip (LOC) approach. The potency of CFBS was also evaluated on catheter tubing and PDMS surfaces (representative bioimplants). The efficacy of CFBS was also demonstrated through the reduction in surface tension, interfacial tension, contact angle and low critical micelle concentration. Conclusion: CFBS was found to be a potent antimicrobial and antibiofilm agent. We believe that perhaps this is the first report on demonstrating the inhibiting effect of Lactobacillus spp. derived CFBS against selected bacteria via LOC approach. These findings can be explored to design various BSs based formulations exhibiting antimicrobial, antibiofilm and antiadhesive potential for biomedical applications