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OALib Journal期刊

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KARAKTERISTIK SPEKTROSKOPI KOMPONEN ANTIBAKTERI BIJI ATUNG (Parinarium glaberrimum Hassk) [Spectroscopic Characteristics of Antibacterial Component of Atung (Parinarium glaberrimum Hassk) Seeds]
Murhadi1),Soewarno T Soekarto2),Betty S.L Jennie2),Anton Apriyantono2)
Jurnal Teknologi dan Industri Pangan , 2004,
Abstract: Relative purity assay on antibacterial components (isolates) of “atung” seeds using HPLC system (linier gradient of water-methanol, detection on UV at 280/254 nm) showed that the isolate-9 had the highest purity (94%), followed by isolate-6 (69%), isolate-7 (66%), and isolate-12 (66%) respectively; while the other isolates only had 50% of purity. The UV-Visible spectrophotometer analysis on the isolate-9, showed that the λmax (in methanol) were at 213 and 269 nm. From IR spectrum of the isolate, no more information can be obtained except the presence of C-H stretching. Furthermore, the MS spectrum showed that the fragment ion series of 44 (100%), 57, 69, 83, 97, 115, maybe predicted as aliphatic amine compounds.
Ultra-Rapid Relief of Skin Pruritus by a 10% High-Concentration 35 kDa Hyaluronic Acid Fragment Gel: A Case Series  [PDF]
Fenghe Xu, Xiaoxiao Jia, Jessica H. Hui, Vera Gorbunova, Mizhou Hui
Journal of Biosciences and Medicines (JBM) , 2026, DOI: 10.4236/jbm.2026.142029
Abstract: High concentrations of hyaluronic acid (HA) have been associated with reduced itch responses in certain biological systems, suggesting a potential role for HA fragments in pruritus modulation. This case series evaluated the preliminary efficacy and safety of a 10% high-concentration 35 kDa HA fragment gel (HA35 gel) for the management of human skin pruritus. Methods: This case series included five patients with moderate-to-severe pruritus of diverse etiologies, including eczema, neurodermatitis, insect bites, urticaria, and postoperative wound–associated pruritus. HA35 gel was applied topically to affected areas. Pruritus intensity was assessed using a Numerical Rating Scale (NRS) at baseline and selected post-application time points, including an early patient-reported onset assessment at approximately 10 seconds and extended follow-up intervals of up to 24 hours, depending on individual symptom evolution. Results: Across all cases, topical application of HA35 gel was associated with a rapid reduction in pruritus intensity, with marked relief reported within seconds after application. In most patients, symptom control persisted for several hours, with sustained relief observed for approximately 8 - 12 hours. No local irritation, allergic reactions, or other adverse skin events were reported during the observation period. Conclusion: In this small case series, topical application of a 10% high-concentration HA35 gel was associated with rapid and sustained alleviation of pruritus across different etiologies, accompanied by improvement in inflammatory skin signs. These findings should be interpreted as hypothesis-generating and suggest that HA35 gel may represent a potential fast-acting, non-steroidal topical option for pruritus management, warranting further controlled investigation.
Methods for the Determination of Stable Isotopes of Carbon and Nitrogen Directly in Valine, Proline, Glutamine, and Glutamic Acid  [PDF]
Lamzira Farulava, Levani Eliashvili, Vakhtang Betlemidze, Bachana Sulava
American Journal of Analytical Chemistry (AJAC) , 2023, DOI: 10.4236/ajac.2023.1410027
Abstract: Amino acids are very important compounds for the body and are involved in important functions that keep us healthy. Amino acids are essential components such as valine, proline, glutamine and glutamic acid. They can be synthesized either naturally or artificially. To examine the metabolism and regulate the synthesis process, compounds labeled with nitrogen or carbon isotopes need to be used. These isotopic compounds allow for more extensive research and enable studies that would otherwise be impossible. However, their use is dependent on the availability of simple, efficient methods for isotopic analysis. Currently, the determination of the atomic fraction of carbon and nitrogen isotopes is only possible through their conversion into molecular nitrogen or carbon monoxide or carbon dioxide. This leads to the loss of information about isotopic enrichment in specific centers of the molecule. This article explores a new direct approach to determining the atomic fraction of carbon and nitrogen isotopes in the isotope-modified or identical centers of these compounds. This method eliminates the transfer process and dilution due to nitrogen and carbon impurities. It is now possible to simultaneously determine the atomic fraction of nitrogen and carbon isotopes in the research substance. This method can be applied to amino acids, making it an effective tool for proposing new research methods. Several articles [1] [2] [3] have proposed similar methods for organic compounds and amino acids.
Determination of Carbon and Nitrogen Isotope Fractions in Tartaric Acid, Oxalic Acid, Glucose and Fructose
—National Center of High Technologies of Georgia  [PDF]
Lamzira Pharulava, Levani Eliashvili, Vakhtang Betlemidze, Bachana Sulava
American Journal of Analytical Chemistry (AJAC) , 2024, DOI: 10.4236/ajac.2024.158015
Abstract: Tartaric acid, oxalic acid, glucose, and fructose are highly important compounds. A comprehensive study of these substances is fascinating from a scientific perspective. They are key components found in wine, vegetables, and fruits. Understanding the isotopic compositions in organic compounds is crucial for comprehending various biochemical processes and the nature of substances present in different natural products. Tartaric acid, oxalic acid, glucose, and fructose are widely distributed compounds, including in vegetables and fruits. Tartaric acid plays a significant role in determining the quality and taste properties of wine, while oxalic acid is also prevalent but holds great interest for further research, especially in terms of carbon isotopic composition. We can unveil the mechanisms of processes that were previously impossible to study. Glucose and fructose are the most common monosaccharides in the hexose group, and both are found in fruits, with sweeter fruits containing higher amounts of these substances. In addition to fruits, wheat, barley, rye, onions, garlic, lentils, peppers, dried fruits, beans, broccoli, cabbage, tomatoes, and other foods are also rich sources of fructose and glucose. To determine the mass fraction of the carbon-13 isotope in these compounds, it is important to study their changes during natural synthesis. These compounds can be modified with a carbon center. According to the existing isotopic analysis method, these compounds are converted into carbon oxide or dioxide [1]. At this point, the average carbon content in the given compound is determined, but information about isotope-modified centers is lost. Dilution may occur through the transfer of other carbon-containing organic compounds in the sample or by dilution with natural carbon or carbon dioxide during the transfer process. This article discusses the possibility of carbon-13 isotope propagation directly in these compounds, both completely modified and modified with individual carbon centers. The literature provides information on determining carbon-13 substance in organic compounds, both with a general approach and for individual compounds [2] [3].
Multifactorial Understanding of Ion Abundance in Tandem Mass Spectrometry Experiments
Bruce R Southey,Jonathan V. Sweedler,L. Rodriguez-Zas,Zeeshan Fazal
- , 2013, DOI: 10.4172/jpb.1000256
Abstract: In a bottom-up shotgun approach, the proteins of a mixture are enzymatically digested, separated, and analyzed via tandem mass spectrometry. The mass spectra relating fragment ion intensities (abundance) to the mass-tocharge are used to deduce the amino acid sequence and identify the peptides and proteins. The variables that influence intensity were characterized using a multi-factorial mixed-effects model, a ten-fold cross-validation, and stepwise feature selection on 6,352,528 fragment ions from 61,543 peptide ions. Intensity was higher in fragment ions that did not have neutral mass loss relative to any mass loss or that had a +1 charge state. Peptide ions classified for proton mobility as non-mobile had lowest intensity of all mobility levels. Higher basic residue (arginine, lysine or histidine) counts in the peptide ion and low counts in the fragment ion were associated with lower fragment ion intensities. Higher counts of proline in peptide and fragment ions were associated with lower intensities. These results are consistent with the mobile proton theory. Opposite trends between peptide and fragment ion counts and intensity may be due to the different impact of factor under consideration at different stages of the MS/MS experiment or to the different distribution of observations across peptide and fragment ion levels. Presence of basic residues at all three positions next to the fragmentation site was associated with lower fragment ion intensity. The presence of proline proximal to the fragmentation site enhanced fragmentation and had the opposite trend when located distant from the site. A positive association between fragment ion intensity and presence of sulfur residues (cysteine and methionine) on the vicinity of the fragmentation site was identified. These results highlight the multi-factorial nature of fragment ion intensity and could improve the algorithms for peptide identification and the simulation in tandem mass spectrometry experiments.
Case Report: Osteochondral Fragment—A Rare Cause of Locked Metacarpophalangeal Joint  [PDF]
Kelvin Ramsey, S. Overstall, A. Fleming
Surgical Science (SS) , 2011, DOI: 10.4236/ss.2011.26076
Abstract: We describe the presentation of a patient with sudden, sharp pain associated with a snapping sensation, swelling and pain over the metacarpophalangeal joint (MCPJ) with no history of direct trauma. The finger was held in 30 degrees of flexion and significantly deviated to the ulnar side with loss of extension. A diagnosis of traumatic rupture of the radial sagittal band of the extensor mechanism was made but the cause at exploration was found to be impingement of an osteochondral fracture fragment. This is a rare cause of irreducible loose body ‘locking’ of the metacarpophalangeal joint.
Unusual Cause of Acute Appendicitis: Bone Fragment  [PDF]
Leh Bi Kalou Ismaèl, Anzoua Kouakou Ibrahim, N’Dri Ahou Bernadette, Ekra Amos Serge, Kouakou Blaise Amos, Dager Nahed, Bittar Issam, Emmanuel Gruss
Surgical Science (SS) , 2023, DOI: 10.4236/ss.2023.143025
Abstract: Foreign bodies are a rare cause of appendicitis, because in most cases these ingested foreign bodies cross the digestive tract asymptomatically [1] [2] [3]. However, some penetrate the lumen of the appendix causing its inflammation. We report an unusual observation of acute appendicitis induced by a foreign body namely a bone fragment in the visceral surgery department of the Centre Hospitalier Intercommunal de Villeneuve Saint-Georges.
Preliminary study on molecular mechanism of lotus mutants induced by ion implantation
离子注入诱变莲花突变体分子机理的初步研究
DENG Chuan-Liang,JIA Yan-Yan,REN Ying-Xue,GAO Wu-Jun,ZHANG Tao,LI Peng-Fei,LU Long-Dou,
邓传良,贾彦彦,任映雪,高武军,张涛,李鹏飞,卢龙斗
遗传 , 2011,
Abstract: Ion implantation, as a new biophysically mutagenic technique, has shown a great potential for horticultural plant breeding. Up to date, little is known about the mutation mechanism of ion implantation at the DNA level. To reveal the mutation effect of Fe+ ion implantation on Baiyangdian red lotus, the random amplified polymorphic DNA (RAPD) was used, and then the bands of mutants and the control in the radiation-sensitive sites were cloned to be sequenced for comparing their DNA sequences. The results indicated that the total base mutation rate of mutants was 0.87%, and there was different in the six mutants. The types of base changes included base transition, transversion, deletion, and insertion. Among the 159 base changes detected, the frequency of single base substitutions (61.01%) was higher than that of base deletions and insertions (38.99%), and the frequency of base transitions (44.65%) was 2.7 times of that of the base transversions (16.35%). The transitions between C and T accounted for largest proportion, A→G transitions and A→T transversions were also present at high frequency. Adenine, thymine, guanine or cytosine could be replaced by any of other three bases, except that there was no C → G substitution. However, thymine was more sensitive to the irradiation than other bases. In our study, we found many purine bases around the purine mutational sites, and many pyrimidine bases around the pyrimidine mutational sites. These will further help us to understand the mechanism of mutagenesis by ion implantation.
Nonextensivity and Tsallis Entropy in DNA Fragmentation Patterns by Ionizing Radiation  [PDF]
Carlos Antonio Marante Valdés, Fidel Antonio Castro Smirnov, Oscar Rodríguez Hoyos, Jo？o Dias de Toledo Arruda-Neto
Journal of Modern Physics (JMP) , 2012, DOI: 10.4236/jmp.2012.36059
Abstract: Nonextensive statistical mechanics as in Tsallis formalism was used in this study, along with the dynamical Hamiltonian rod-like DNA model and the maximum entropy criteria for Tsallis’ entropy, so as to obtain length distribution of plasmid fragments, after irradiation with very high doses, assuming that the system reaches metaequilibrium. By intensively working out the Grand Canonical Ensemble (used to take into account the variation of the number of base pairs) a simplified expression for Fragment Size Distribution Function (FSDF) was obtained. This expression is dependent on two parameters only, the Tsallis q value and the minimal length of the fragments. Results obtained from fittings to available experimental data were adequate and the characteristic behavior of the shortest fragments was clearly documented and reproduced by the model, a circumstance never verified from theoretical distributions. The results point to the existence of an entropy which characterizes fragmentation processes and depending only on the q entropic index.
Correlation between Solar Semi-Diameter and Geomagnetic Time Series  [PDF]
Eugênio Reis Neto, Vitor Hugo Alves Dias, Andrés Reinaldo Rodriguez Papa, Alexandre Humberto Andrei, Jucira Lousada Penna, Irineu Figueiredo, Sérgio Calderari Boscardin, Victor de Amorin d’ávila
International Journal of Geosciences (IJG) , 2012, DOI: 10.4236/ijg.2012.32034
Abstract: We study the correlation between geomagnetic and solar semi-diameter measurements made at two of our ground stations (Vassouras and Rio de Janeiro, Brazil). The study comprises the period from March 1998 to November 2003, for which daily means were compared. Both series describe correlated, but different, phenomena and, consequently, before a correlation study, an individual analysis of each data set was necessary. One of the motivations of the present work was to further explore the correlation with lags found between the solar semi-diameter and some solar activity estimators, which supports the probabilistic forecasting of the solar activity and hence, of the solar driven geomagnetic variations.
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