Aktivitas Antibakteri Ekstrak Rumput Laut Eucheuma Cottoni Terhadap Bakteri Escherichia Coli, Staphylococcus Aureus, Vibrio Cholera Dan Salmonella Typhosa

Seaweed (Eucheuma cottonii) is one of the marine biological resources that contain flavonoid compounds as antibacterial agents. In a previous study the antibacterial Eucheuma cottonii, had been performed by dipping the disc paper into antibacterial extract, while in this study the antibacterial extract in exact volume will be dropped onto the disc paper, so we will know the volume certainty. The aims of the study were to determine the antibacterial activity and the minimum inhibitory concentration of the extract of Eucheuma cottonii test bacteria by using methanol solvent. The study was conducted in September-October 2012. In this study, seaweed extract made by using maceration method while the antibacterial activity testing by using agar diffusion method. The study results showed that the extract of Eucheuma cottonii antibacterial activity inhibited the growth of Staphylococcus aureus with inhibition zone diameter 17.33 mm, Escherichia coli with inhibition zone diameter 16,33 mm, Vibrio cholera with inhibition zone diameter 13,67 mm and Salmonella typhosa with inhibition zone diameter 11,67 mm. Minimum inhibitory concentration of Eucheuma cottonii to Escherichia coli, Staphylococcus aureus and Vibrio cholera were at 1% concentration while Salmonella typhosa was at 5 % concentration

Antibacterial Activity Assay of Mangrove Extracts Against Salmonella Typhi and Listeria Monocytogenes

The antibacterial activities of mangrove species, Avicennia marina, Sonneratia caseolaris (collected from Teluk Payo, Banyuasin, South Sumatera), Ceriops tagal, Rizhopora apiculata, and Sonneratia alba (collected from Sadai, South Bangka) were screened against Salmonella typhi and Listeria monocytogenes by agar disk diffusion assays. Extractions were conducted using organic solvents (methanol, ethyl acetate, and acetone, subsequently). Most of the extracts tested showed potential antibacterial activity against both pathogens. The methanol extracts of the bark from S. alba and the fruit from A. marina showed particularly large inhibition zones (15 mm) against S. typhi. The acetone extract of S. alba leaves showed the largest inhibition zone (14 mm) when tested against L. Monocy-togenes. Further partial purifications of selected extracts which showed strong inhibition were performed by silica gel column chromatography using various eluent compositions with different polarities. The third fraction of methanol extract from S.alba leaves eluted with chloroform:methanol (1:5) resulted in a remarkably large inhibition zone (23 mm) against S. typhi. The third and seventh fractions of acetone extract from S. alba leaves eluted with ethyl acetate:methanol (7:3) resulted in a large inhibition zones (15 mm) against L. monocytogenes. In addition, the sixth fraction of methanol extract from A. marina fruit eluted with chloroform : methanol (6:4) resulted in the largest inhibition zone (17 mm) against L. monocytogenes. These results indicated that mangrove extracts could be developed as potential biomaterials for biopharmaceutical as well as biopreservation industries

Reliable intraocular pressure measurement using automated radio-wave telemetry

Purpose To present an autonomous intraocular pressure (IOP) measurement technique using a wireless implantable transducer (WIT) and a motion sensor. Methods: The WIT optical aid was implanted within the ciliary sulcus of a normotensive rabbit eye after extracapsular clear lens extraction. An autonomous wireless data system (AWDS) comprising of a WIT and an external antenna aided by a motion sensor provided continuous IOP readings. The sensitivity of the technique was determined by the ability to detect IOP changes resulting from the administration of latanoprost 0.005% or dorzolamide 2%, while the reliability was determined by the agreement between baseline and vehicle (saline) IOP. Results: On average, 12 diurnal and 205 nocturnal IOP measurements were performed with latanoprost, and 26 diurnal and 205 nocturnal measurements with dorzolamide. No difference was found between mean baseline IOP (13.08±2.2 mmHg) and mean vehicle IOP (13.27±2.1 mmHg) (P=0.45), suggesting good measurement reliability. Both antiglaucoma medications caused significant IOP reduction compared to baseline; latanoprost reduced mean IOP by 10% (1.3±3.54 mmHg; P<0.001), and dorzolamide by 5% (0.62±2.22 mmHg; P<0.001). Use of latanoprost resulted in an overall twofold higher IOP reduction compared to dorzolamide (P<0.001). Repeatability was ±1.8 mmHg, assessed by the variability of consecutive IOP measurements performed in a short period of time (≤1 minute), during which the IOP is not expected to change. Conclusion: IOP measurements in conscious rabbits obtained without the need for human interactions using the AWDS are feasible and provide reproducible results

Reliable intraocular pressure measurement using automated radio-wave telemetry

Purpose To present an autonomous intraocular pressure (IOP) measurement technique using a wireless implantable transducer (WIT) and a motion sensor. Methods: The WIT optical aid was implanted within the ciliary sulcus of a normotensive rabbit eye after extracapsular clear lens extraction. An autonomous wireless data system (AWDS) comprising of a WIT and an external antenna aided by a motion sensor provided continuous IOP readings. The sensitivity of the technique was determined by the ability to detect IOP changes resulting from the administration of latanoprost 0.005% or dorzolamide 2%, while the reliability was determined by the agreement between baseline and vehicle (saline) IOP. Results: On average, 12 diurnal and 205 nocturnal IOP measurements were performed with latanoprost, and 26 diurnal and 205 nocturnal measurements with dorzolamide. No difference was found between mean baseline IOP (13.08±2.2 mmHg) and mean vehicle IOP (13.27±2.1 mmHg) (P=0.45), suggesting good measurement reliability. Both antiglaucoma medications caused significant IOP reduction compared to baseline; latanoprost reduced mean IOP by 10% (1.3±3.54 mmHg; P<0.001), and dorzolamide by 5% (0.62±2.22 mmHg; P<0.001). Use of latanoprost resulted in an overall twofold higher IOP reduction compared to dorzolamide (P<0.001). Repeatability was ±1.8 mmHg, assessed by the variability of consecutive IOP measurements performed in a short period of time (≤1 minute), during which the IOP is not expected to change. Conclusion: IOP measurements in conscious rabbits obtained without the need for human interactions using the AWDS are feasible and provide reproducible results

Research Priorities on the Role of α-Synuclein in Parkinson\u27s Disease Pathogenesis

\ua9 2024 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.Various forms of Parkinson\u27s disease, including its common sporadic form, are characterized by prominent α-synuclein (αSyn) aggregation in affected brain regions. However, the role of αSyn in the pathogenesis and evolution of the disease remains unclear, despite vast research efforts of more than a quarter century. A better understanding of the role of αSyn, either primary or secondary, is critical for developing disease-modifying therapies. Previous attempts to hone this research have been challenged by experimental limitations, but recent technological advances may facilitate progress. The Scientific Issues Committee of the International Parkinson and Movement Disorder Society (MDS) charged a panel of experts in the field to discuss current scientific priorities and identify research strategies with potential for a breakthrough. \ua9 2024 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society

Le Numidien de la Tunisie septentrionale: données stratigraphiques et interprétation géodynamique

The Numidian flysch consists of a thick turbiditic sandy and clayey formation of Oligocene-Lower Miocene age which outcrops largely in northern Tunisia. Concerning the relationship between the Numidian formation and its «substratum», two hypothesis are discussed : i) allochtonous Numidian units (tangential abnormal contact) ; ii) autochtonous Numidian units (sedimentary contact : locally downlap). Detailed investigation undertaken in the study area, based on the survey and the dating of lithological logs, coupled with geodynamic and petrogenetic events, lead to the following results : i) absence of tangential tectonic contact in the base of Numidian series ; ii) a significant Tertiary tectonics attested by several phases. Moreover, the Numidian siliciclastic series are affected, like the other Tertiary formations in the North of Tunisia, by south-east ward deep-seated thrusts, oriented N50-60.El flysch Numidiense es una formación arenisco-arcillosa de gran espesor y de edad Oligoceno-Mioceno inferior, que aflora en el norte de Túnez. La naturaleza del contacto basal de esta formación ha suscitado numerosas discusiones. De ellas destacan dos hipótesis: 1) las unidades numidienses alóctonas se apoyan en forma de contacto anormal tangencial, y 2) se trata de unidades autóctonas (contacto sedimentario normal, a veces de tipo "downlap").El levantamiento de cortes litológicos detallados y su datación, combinado con datos de tipo geodinámico y petrogenético, ha permitido confirmar la ausencia de un contacto tectónico tangencial en la base del Numidiense y por el contrario, establecer la existencia de una significativa tectónica terciaria desarrollada en varias fases. Asi, las series siliciclásticas Numidienses se ven afectadas, como otras formaciones terciarias del norte de Túnez, por cabalgamientos de vergencia SE

Modeling oscillatory Microtubule--Polymerization

Polymerization of microtubules is ubiquitous in biological cells and under certain conditions it becomes oscillatory in time. Here simple reaction models are analyzed that capture such oscillations as well as the length distribution of microtubules. We assume reaction conditions that are stationary over many oscillation periods, and it is a Hopf bifurcation that leads to a persistent oscillatory microtubule polymerization in these models. Analytical expressions are derived for the threshold of the bifurcation and the oscillation frequency in terms of reaction rates as well as typical trends of their parameter dependence are presented. Both, a catastrophe rate that depends on the density of {\it guanosine triphosphate} (GTP) liganded tubulin dimers and a delay reaction, such as the depolymerization of shrinking microtubules or the decay of oligomers, support oscillations. For a tubulin dimer concentration below the threshold oscillatory microtubule polymerization occurs transiently on the route to a stationary state, as shown by numerical solutions of the model equations. Close to threshold a so--called amplitude equation is derived and it is shown that the bifurcation to microtubule oscillations is supercritical.Comment: 21 pages and 12 figure