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991.
Mohd Shahrir Abdul Halim Soehardy Zainudin Rozita Mohamad Loo C Yuen Rashidi Saidin Norella Kong 《Journal of medical case reports》2010,4(1):1-2
Introduction
Esophageal intramural pseudodiverticulosis is a rare condition characterized by the dilatation of the submucosal glands.Case presentation
We present a case of esophageal intramural pseudodiverticulosis in a 72-year-old Caucasian man who presented with dysphagia and with a background history of alcohol abuse. An upper gastrointestinal endoscopy of our patient showed an esophageal stricture with abnormal mucosal appearances, but no malignant cells were seen at biopsy. Appearances on a barium esophagram were pathognomonic for esophageal intramural pseudodiverticulosis.Conclusion
We demonstrate the enduring usefulness of barium esophagography in the characterization of abnormal mucosal appearances at endoscopy. 相似文献992.
993.
Roghayeh Abedi Karjiban Mohd Basyaruddin Abdul Rahman Mahiran Basri Abu Bakar Salleh Donald Jacobs Habibah Abdul Wahab 《The protein journal》2009,28(1):14-23
Molecular Dynamics (MD) simulations have been used to understand how protein structure, dynamics, and flexibility are affected
by adaptation to high temperature for several years. We report here the results of the high temperature MD simulations of
Bacillus stearothermophilus L1 (L1 lipase). We found that the N-terminal moiety of the enzyme showed a high flexibility and dynamics during high temperature
simulations which preceded and followed by clear structural changes in two specific regions; the small domain and the main
catalytic domain or core domain of the enzyme. These two domains interact with each other through a Zn2+-binding coordination with Asp-61 and Asp-238 from the core domain and His-81 and His-87 from the small domain. Interestingly,
the His-81 and His-87 were among the highly fluctuated and mobile residues at high temperatures. The results appear to suggest
that tight interactions of Zn2+-binding coordination with specified residues became weak at high temperature which suggests the contribution of this region
to the thermostability of the enzyme.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
994.
Naz Chaibakhsh Mohd Basyaruddin Abdul Rahman Suraini Abd-Aziz Mahiran Basri Abu Bakar Salleh Raja Noor Zaliha Raja Abdul Rahman 《Journal of industrial microbiology & biotechnology》2009,36(9):1149-1155
Immobilized Candida antarctica lipase-catalyzed esterification of adipic acid and oleyl alcohol was investigated in a solvent-free system (SFS). Optimum
conditions for adipate ester synthesis in a stirred-tank reactor were determined by the response surface methodology (RSM)
approach with respect to important reaction parameters including time, temperature, agitation speed, and amount of enzyme.
A high conversion yield was achieved using low enzyme amounts of 2.5% w/w at 60°C, reaction time of 438 min, and agitation
speed of 500 rpm. The good correlation between predicted value (96.0%) and actual value (95.5%) implies that the model derived
from RSM allows better understanding of the effect of important reaction parameters on the lipase-catalyzed synthesis of adipate
ester in an organic solvent-free system. Higher volumetric productivity compared to a solvent-based system was also offered
by SFS. The results demonstrate that the solvent-free system is efficient for enzymatic synthesis of adipate ester. 相似文献
995.
Seong-Koon Lo Norlelawati Arifin Ling-Zhi Cheong Chin-Ping Tan Kamariah Long Mohd. Suria Affandi Yusoff Oi-Ming Lai 《Journal of Molecular Catalysis .B, Enzymatic》2009,57(1-4):136-144
A dual response approach using diacylglycerol (DAG) and triacylglycerol (TAG) as responses for optimization of 1-stearoyl-3(2)-oleoyl glycerol-enriched DAG synthesis using response surface methodology (RSM) was investigated. Four variables from a lipase-catalyzed esterification reaction were optimized using a central composite rotatable design. The following optimized conditions yielded 51 wt.% DAG and 22 wt.% TAG: reaction temperature of 55 °C, enzyme dosage of 9.5 wt.%, fatty acid/glycerol molar ratio of 2.1 and reaction time of 3 h. Results were repeatable at 10 kg production scale in a pilot packed-bed enzyme reactor. No significant losses in enzyme activity or changes in fatty acid selectivity on DAG synthesis were observed during the five pilot productions. Lipozyme RM IM showed selectivity towards the production of stearic acid enriched DAG. The purity of DAG oil after purification was 90 wt.%. 相似文献
996.
Kaur M Singh K Rup PJ Saxena AK Khan RH Ashraf MT Kamboj SS Singh J 《Archives of biochemistry and biophysics》2006,445(1):156-165
An anti-insect and anti-cancer lectin has been isolated from Arisaema helleborifolium Schott by affinity chromatography using asialofetuin-linked amino activated silica beads. The bound A. helleborifolium lectin (AHL) was eluted with 100mM glycine-HCl buffer, pH 2.5. It gave a single band on SDS-PAGE, pH 8.3, and PAGE, pH 4.5. However, multiple bands were obtained in PAGE at pH 8.3 and isoelectric focusing. The lectin was a homotetramer having subunit molecular mass 13.4kDa while its native molecular mass was 52kDa. It was a glycoprotein with 3.40% carbohydrate and was stable up to 60 degrees C for 30min. It showed anti-insect activity towards second instar larvae of Bactrocera cucurbitae (Coquillett) with LC(50) value of 16.4microg/ml. Larvae fed on artificial diet containing sub-lethal dose of AHL showed a significant decrease in acid phosphatase and alkaline phosphatase activity while esterase activity markedly increased as compared to larvae fed on diet without lectin. AHL was also found to inhibit in vitro proliferation of some well established human cancer cell lines viz HOP-62 (95%), HCT-15 (92%), HEP-2 (66%), HT-29 (68%), PC-3 (39.4%), and A-549 (20.7%). 相似文献
997.
Muhammad Faris Abdul Aziz Marina Mohd. Top @ Mohd. Tah Shamarina Shohaimi Nurul Izza Ab Ghani Christine Fletcher 《Ecology and evolution》2021,11(16):10741
A research study on morphometrics of Kalophrynus palmatissimus (commonly known as Lowland Grainy Frog) at Ayer Hitam Forest Reserve (AHFR), Selangor and Pasoh Forest Reserve (PFR), Negeri Sembilan was carried out from 12 November 2016 to 13 September 2017. The study was to examine data on the morphometric traits of K. palmatissimus at the two forest reserves. 15 morphometric traits of K. palmatissimus that were taken by using vernier calipers. Frog surveys were done by using 15 and 18 nocturnal 400 m transect lines with an interval distance of 20 m at AHFR and PFR, respectively. The GPS coordinates for all frog samples were recorded to ensure the precise geographic location. In addition, five climatic data were recorded. The results showed that most morphometric traits in AHFR (n = 34) and PFR (n = 31) were positively correlated with each other. On the other hand, climatic factor, which was soil pH, had a significant positive influence on most of the morphometric traits (p < .01), except for tympanum diameter and upper eyelid width (p ≥ .05). Meanwhile, the temperature had a significantly negative influence on all morphometric traits (p < .01). General linear model (GLM) analysis showed that snout‐vent length (SVL) influenced most morphometric traits (F ≤ 80.86, p < .01), except for hand length (HAL: F = 0.299, p > .05). Later, it was found that the snout‐vent length of K. palmatissimus at AHFR was slightly larger than at PFR (AHFR: μ = 37.00 mm, SE = 1.16 c.f. PFR: μ = 30.29 mm, SE = 1.07). It showed that there were variations in morphometric traits of K. palmatissimus at AHFR and PFR. From PCA analysis, morphometric traits are grouped into two components for AHFR and PFR, respectively. In AHFR, head length, eye diameter, head width, internarial distance, interorbital distance, forearm length, tibia length, foot length, and thigh length were strongly correlated, while snout length and eye‐nostril distance were strongly correlated. In PFR, eye diameter, head width, internarial distance, interorbital distance, foot length, and thigh length were strongly correlated, though snout length and eye‐nostril distance were strongly correlated, hence, suggested that all morphometric traits grow simultaneously in K. palmatissimus with eye‐nostril distance (EN), and snout length (SL) growing almost simultaneously at AHFR (r = .91) and PFR (r = .97). There is still a lack of available information regarding the distribution and morphometric studies of K. palmatissimus in Malaysia, especially at AHFR and PFR. This study showed 15 different morphometric traits of K. palmatisssimus between AHFR and PFR, with K. palmatissimus at AHFR were found to be slightly larger than at PFR. 相似文献
998.
Mechanism of oligomerisation of cyclase-associated protein from Dictyostelium discoideum in solution
Yusof AM Jaenicke E Pedersen JS Noegel AA Schleicher M Hofmann A 《Journal of molecular biology》2006,362(5):1072-1081
Cyclase-associated protein (CAP) is a highly conserved modular protein implicated in the regulation of actin filament dynamics and a variety of developmental and morphological processes. The protein exists as a high molecular weight complex in cell extracts and purified protein possesses a high tendency to aggregate, a major obstacle for crystallisation. Using a mutagenesis approach, we show that two structural features underlie the mechanism of oligomerisation in Dictyostelium discoideum CAP. Positively charged clusters on the surface of the N-terminal helix-barrel domain are involved in inter-molecular interactions with the N or C-terminal domains. Abolishing these interactions mainly renders dimers due to a domain swap feature in the extreme C-terminal region of the protein that was previously described. Based on earlier studies with yeast CAP, we also generated constructs with mutations in the extreme N-terminal region of Dictyostelium CAP that did not show significantly altered oligomerisation behaviour. Constructs with mutations in the earlier identified protein-protein interaction interface on the N-terminal domain of CAP could not be expressed as soluble protein. Assessment of the soluble proteins indicates that the mutations did not affect their overall fold. Further studies point to the correlation between stability of full-length CAP with its multimerisation behaviour, where oligomer formation leads to a more stable protein. 相似文献
999.
Siti Najwa-Sawawi Nur Munira Azman Mohd Uzair Rusli Amirrudin Ahmad Muhammad Fahmi-Ahmad Nik Fadzly 《Saudi Journal of Biological Sciences》2021,28(9):5053-5060
Sea turtle eggs incubation involves natural and artificial incubation of eggs, and indeed the depth will be varied and presumably affect the development of hatchlings. For nest relocation, the researcher needs to decide on the depth to incubate the eggs. Sea turtle eggs clutches may vary between 40 and 120 eggs for the green turtle, thus using a single value as the standard procedure might affect the quality of hatchlings. Here we quantify the dimension of the natural (in-situ) nest constructed by the nester and the artificial (ex-situ) built by our ranger during nest relocation. We suggest a linear regression calculation of Y = 0.2366X + 59.3267, better predict a more accurate nest depth based on the number of eggs to imitate the natural nest. 相似文献
1000.
Gokula Kumar Appalanaido Syadwa Abdul Shukor Ang Soo Fan Soon Eu Chong Hasma Hussin Noor Khairiah A. Karim Leow Voon Meng Mohd Zahri Abdul Aziz 《Reports of Practical Oncology and Radiotherapy》2021,26(4):647
Brachytherapy (BT) is an important local treatment of tumor and it can be applied to different anatomical sites either in a curative or palliative setting. BT can deliver large dose of radiation to the tumor while sparing the surrounding normal tissue which translates into a better therapeutic ratio compared to external beam radiotherapy. However, the evidence for the use of brachytherapy in the palliative setting is lacking in the literature. In this case report, we describe the brachytherapy technique and outcome of a patient with squamous cell carcinoma of the hypopharynx who underwent palliative brachytherapy to the hypopharynx and metastatic tumor at the right axilla. 相似文献