Displaying publications 1 - 20 of 89 in total

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  1. Maitland HB
    Med J Malaya, 1965 Sep;20(1):8-10.
    PMID: 4221441
    Matched MeSH terms: Freeze Drying*
  2. Tan NH, Tan CS
    Toxicon, 1987;25(11):1249-53.
    PMID: 3433296
    The enzymatic activities of four samples of Malayan cobra venom were investigated. There was significant variation in the contents of L-amino acid oxidase, alkaline phosphomonoesterase, acetylcholinesterase, phospholipase A, 5'-nucleotidase and hyaluronidase. The phosphodiesterase content was, however, constant. Storage of the lyophilized venom powder at 25 degrees C for 1 month did not affect the enzymatic activities. The venom enzymatic activities were generally also stable at 4 degrees C in 0.85% saline solution. After incubation at 37 degrees C for 39 days in 0.85% saline solution, the venom still retained considerable amounts of enzymatic activities. SP-Sephadex C-25 ion-exchange chromatography of the venom showed that the phospholipase A, L-amino acid oxidase, 5'-nucleotidase, phosphodiesterase and alkaline phosphomonoesterase exist in multiple forms.
    Matched MeSH terms: Freeze Drying
  3. Cheong SK, Lim YC, Mok KL
    Malays J Pathol, 1991 Jun;13(1):51-2.
    PMID: 1795563
    Mixed reagents for the Glucose-6-phosphate dehydrogenase (G6PD) deficiency fluorescent screening test were freeze-dried in plastic tubes. The reagents were then reconstituted with distilled water and the test was performed in the usual way. Initial testing with the freeze-dried mixed reagents gave consistent positive reaction to 12 normal blood samples and negative reaction to 9 G6PD deficient blood samples. This will enable a laboratory with freeze-drying facilities to prepare reagent tubes in bulk. As these tubes can be kept at 4 degrees C and do not require to be stored at -20 degrees C, a major laboratory can prepare these tubes and supply small laboratories for screening purposes.
    Matched MeSH terms: Freeze Drying*
  4. Baharuddin, N.A., Kamin, S., Samsuddin, A.R.
    Ann Dent, 2003;10(1):-.
    MyJurnal
    This study evaluated the effectiveness of demineralized freeze-dried bone xenograft in reducing post-surgical pocket depth in moderate to advanced adult periodontitis in patients. Nine patients with a total of eighteen intrabony defects were selected for this study. The bony defects were matched for tooth type, location and pocket depth. Following an initial non-surgical treatment, only pockets of 5 to 7 mm deep were indicated for surgery. Periodontal pockets were measured pre-operatively and at 3, 6 and 9 months post-surgically. The study protocol included a split mouth design, where surgical treatment was carried out at both test and control sites. The test sites were assigned demineralized freeze-dried bone xenograft and the control sites were subjected to debridement alone without the use of demineralized freeze-dried bone xenograft. The results from this study showed a statistically significant difference in the mean pocket depth at 6 and 9 months post-operatively for both test and control groups, but there was no statistically significant difference at 3 months. In conclusion, demineralized freeze-dried bone xenograft was ineffective in reducing periodontal pocket depth in patients with moderate to severe periodontitis, as compared to surgical debridement alone.
    Matched MeSH terms: Freeze Drying
  5. Loqman MY, Wong CM, Hair-Bejo M, Zuki AB, Hafeez YM
    Med J Malaysia, 2004 May;59 Suppl B:113-4.
    PMID: 15468844
    A study was conducted to investigate the effectiveness of freeze-dried bovine pericardium (FDBP) as a biomaterial in diaphragmatic herniorrhapy in dogs. Eight adult dogs were randomly selected and divided into two equal groups. In FDBP group, a diaphragmatic defect was induced and repaired with an identical size of FDBP. In the control group, a diaphragmatic wall was incised at three-side border creating a flap and sutured. Grossly, only mild intrathoracic adhesion was observed for most of the animals, and no herniation occured. Microscopically, the biomaterial incorporated into the host's tissue by ingrowth of young muscle fiber and massive new blood vessel formation in between the fibrous tissue.
    Matched MeSH terms: Freeze Drying
  6. Baharuddin, N.A., Kamin, S., Samsuddin, A.R.
    Ann Dent, 2005;12(1):-.
    MyJurnal
    The aim of this study was to determine the effectiveness of demineralized freeze-dried bone xenograft (DFDBBX) in minimizing post-surgical recession in moderate to advanced adult periodontitis in patients. Nine patients with a total of eighteen intrabony defects were matched for the tooth type, location of defects and periodontal pocket depth (5 to 7mm). Following an initial nonsurgical treatment, recession at defects indicated for surgery was measured pre-operatively. Surgical treatment was carried out by split mouth design, where the test sites were assigned DFDBBX and the control sites were subjected to debridement without the use of DFDBBX. Recessions were measured at 3 months, 6 months and 9 months post-operatively. The results showed no statistically significant difference in mean recession at 3, 6 and 9 months post-operatively compared to baseline for both test and control groups. Thus, DFDBBX was ineffective in minimizing recession on patients with moderate to severe periodontitis, as compared to surgical debridement alone.
    Matched MeSH terms: Freeze Drying
  7. Aziah I, Ravichandran M, Ismail A
    Diagn Microbiol Infect Dis, 2007 Dec;59(4):373-7.
    PMID: 17964105
    Conventional polymerase chain reaction (PCR) testing requires many pipetting steps and has to be transported and stored in cold chain. To overcome these limitations, we designed a ready-to-use PCR test for Salmonella typhi using PCR reagents, primers against the ST50 gene of S. typhi, a built-in internal amplification control (IAC), and gel loading dye mixed and freeze-dried in a single tube. The 2-step dry-reagent-based assay was used to amplify a 1238-bp target gene and an 810-bp IAC gene from 73 BACTEC blood culture broths (33 true positives for S. typhi and 40 true negatives for non-S. typhi). The sensitivity, specificity, positive predictive value, and negative predictive value of the PCR assay were 87.9%, 100%, 100%, and 90.9%, respectively. We suggest that this rapid 2-step PCR test could be used for the rapid diagnosis of typhoid fever.
    Matched MeSH terms: Freeze Drying/methods*
  8. Sim JH, Kamaruddin AH
    Bioresour Technol, 2008 May;99(8):2724-35.
    PMID: 17697778
    Efforts in optimizing reducing agents, cysteine-HCl.H2O and sodium sulfide in order to attain satisfactory responses during acetic acid fermentation have been carried out in this study. Cysteine-HCl.H2O each with five concentrations (0.00-0.50 g/L) was optimized one at a time and followed by sodium sulfide component (0.00-0.50 g/L). Response surface methodology (RSM) was used to determine the optimum concentrations of cysteine-HCl.H2O and sodium sulfide. The statistical analysis showed that the amount of cells produced and efficiency in CO conversion were not affected by sodium sulfide concentration. However, sodium sulfide is required as it does influence the acetic acid production. The optimum reducing agents for acetic acid fermentation was at 0.30 g/L cysteine-HCl.H2O and sodium sulfide respectively and when operated for 60 h cultivation time resulted in 1.28 g/L acetic acid production and 100% CO conversion.
    Matched MeSH terms: Freeze Drying
  9. Kho YS, Vikineswary S, Abdullah N, Kuppusamy UR, Oh HI
    J Med Food, 2009 Feb;12(1):167-74.
    PMID: 19298211 DOI: 10.1089/jmf.2007.0568
    Auricularia auricula-judae is currently grown in Malaysia. In the present study, the methanolic extracts from fruit bodies (fresh, oven-dried, and freeze-dried) and mycelium of A. auricula-judae were evaluated for their antioxidant capacities based on 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity and ferric reducing antioxidant power (FRAP) assay. The total phenolic content in the extracts were also measured. The extract of freeze-dried fruit bodies of A. auricula-judae had potent DPPH free radical scavenging activity with a 50% effective concentration of 2.87 mg/mL, whereas the FRAP value of A. auricula-judae mycelium was 5.22 micromol of FeSO(4).7H(2)O equivalents/g of mycelium sample. Further, a positive correlation (R(2) = 0.7668) between FRAP level of A. auricula-judae extracts and the total phenolic contents was observed. Thus the method of processing of fresh fruit bodies had an effect on the antioxidant potential of A. auricula-judae.
    Matched MeSH terms: Freeze Drying
  10. Mohd Zainol, M.K., Abdul-Hamid A., Abu Bakar, F., Pak Dek, S.
    MyJurnal
    The effect of different drying methods on the degradation of flavonoids in Centella asiatica was evaluated. C. asiatica leaf, root and petiole were dried using air-oven, vacuum oven and freeze drier. Flavonoid was determined utilizing reverse-phase high performance liquid chromatography (RP-HPLC). Results of the study revealed the presence of high concentration of flavonoids in C. asiatica leaf, root and petiole, which include, naringin (4688.8 ± 69 μg/100 g, 3561.3 ± 205 μg/ 100 g, and 978.3 ± 96 μg/ 100 g), rutin (905.6 ± 123 μg/ 100 g, 756.07 ± 95 μg/ 100 g, and 557.25 ± 58 μg/ 100 g), quercetin (3501.1 ± 107 μg/ 100 g, 1086.31 ± 90 μg/ 100 g, and 947.63 ± 83 μg/ 100 g) and catechin (915.87 ± 6.01 μg/ 100 g, 400.6 ± 67 μg/ 100 g, and 250.56 ± 18 μg/ 100g). Luteolin, kaempferol and apigenin on the other hand, were inconsistently present in some parts of C. asiatica. Air-oven treatment resulted in the highest total flavonoids degradation followed by vacuum oven and freeze dried with percent degradation of 97%, 87.6% and 73%, respectively. Catechin and rutin were found to be the most stable flavonoids with percent degradation up to 35%, 66% and 76% for freeze dried, vacuum oven and air oven, respectively.
    Matched MeSH terms: Freeze Drying
  11. Tan SL, Sulaiman S, Pingguan-Murphy B, Selvaratnam L, Tai CC, Kamarul T
    Cell Tissue Bank, 2011 Feb;12(1):59-70.
    PMID: 19953328 DOI: 10.1007/s10561-009-9164-x
    This study investigates the feasibility of processed human amnion (HAM) as a substrate for chondrogenic differentiation of mesenchymal stem cells (MSCs). HAM preparations processed by air drying (AD) and freeze drying (FD) underwent histological examination and MSC seeding in chondrogenic medium for 15 days. Monolayer cultures were used as control for chondrogenic differentiation and HAMs without cell seeding were used as negative control. Qualitative observations were made using scanning electron microscopy analysis and quantitative analyses were based on the sulfated glycosaminoglycans (GAG) assays performed on day 1 and day 15. Histological examination of HAM substrates before seeding revealed a smooth surface in AD substrates, while the FD substrates exhibited a porous surface. Cell attachment to AD and FD substrates on day 15 was qualitatively comparable. GAG were significantly highly expressed in cells seeded on FD HAM substrates. This study indicates that processed HAM is a potentially valuable material as a cell-carrier for MSC differentiation.
    Matched MeSH terms: Freeze Drying
  12. Khoramnia A, Abdullah N, Liew SL, Sieo CC, Ramasamy K, Ho YW
    Anim Sci J, 2011 Feb;82(1):127-35.
    PMID: 21269371 DOI: 10.1111/j.1740-0929.2010.00804.x
    A rotatable central composite design (CCD) was used to study the effect of cryoprotectants (skim milk, sucrose and lactose) on the survival rate of a probiotic Lactobacillus strain, L. reuteri C10, for poultry, during freeze-drying and storage. Using response surface methodology, a quadratic polynomial equation was obtained for response value by multiple regression analyses: Y = 8.59546-0.01038 X(1)-0.09382 X(2)-0.07771 X(3)-0.054861 X(1)(2)-0.04603 X(3)(2)-0.10938 X(1)X(2). Based on the model predicted, sucrose exerted the strongest effect on the survival rate. At various combinations of cryoprotectants, the viability loss of the cells after freeze-drying was reduced from 1.65 log colony forming units (CFU)/mL to 0.26-0.66 log CFU/mL. The estimated optimum combination for enhancing the survival rate of L. reuteri C10 was 19.5% skim milk, 1% sucrose and 9% lactose. Verification experiments confirmed the validity of the predicted model. The storage life of freeze-dried L. reuteri C10 was markedly improved when cryoprotectants were used. At optimum combination of the cryoprotectants, the survival rates of freeze-dried L. reuteri C10 stored at 4°C and 30°C for 6 months were 96.4% and 73.8%, respectively. Total viability loss of cells which were not protected by cryoprotectants occurred after 12 and 8 weeks of storage at 4°C and 30°C, respectively.
    Matched MeSH terms: Freeze Drying*
  13. Krishnamurithy G, Shilpa PN, Ahmad RE, Sulaiman S, Ng CL, Kamarul T
    J Biomed Mater Res A, 2011 Dec 01;99(3):500-6.
    PMID: 21913317 DOI: 10.1002/jbm.a.33184
    Human amniotic membrane (HAM) is an established biomaterial used in many clinical applications. However, its use for tissue engineering purposes has not been fully realized. A study was therefore conducted to evaluate the feasibility of using HAM as a chondrocyte substrate/carrier. HAMs were obtained from fresh human placenta and were process to produced air dried HAM (AdHAM) and freeze dried HAM (FdHAM). Rabbit chondrocytes were isolated and expanded in vitro and seeded onto these preparations. Cell proliferation, GAG expression and GAG/cell expression were measured at days 3, 6, 9, 12, 15, 21, and 28. These were compared to chondrocytes seeded onto plastic surfaces. Histological analysis and scanning electron microscopy was performed to observe cell attachment. There was significantly higher cell proliferation rates observed between AdHAM (13-51%, P=0.001) or FdHAM (18-48%, p = 0.001) to chondrocytes in monolayer. Similarly, GAG and GAG/cell expressed in AdHAM (33-82%, p = 0.001; 22-60%, p = 0.001) or FdHAM (41-81%, p = 0.001: 28-60%, p = 0.001) were significantly higher than monolayer cultures. However, no significant differences were observed in the proliferation rates (p = 0.576), GAG expression (p = 0.476) and GAG/cell expression (p = 0.135) between AdHAM and FdHAM. The histology and scanning electron microscopy assessments demonstrates good chondrocyte attachments on both HAMs. In conclusion, both AdHAM and FdHAM provide superior chondrocyte proliferation, GAG expression, and attachment than monolayer cultures making it a potential substrate/carrier for cell based cartilage therapy and transplantation.
    Matched MeSH terms: Freeze Drying
  14. Lee SV, Tai ES, Mutalib AR, Khairani-Bejo S, Bahaman AR
    Trop Biomed, 2011 Dec;28(3):497-505.
    PMID: 22433877 MyJurnal
    A simple and reliable tool for the early diagnosis of leptospirosis is urgently needed. We report the development of a lyophilized reagent-based polymerase chain reaction (PCR) assay targeting lipL32 gene, which is present only in pathogenic leptospires. To determine the effectiveness of the newly developed assay in the early diagnosis of leptospirosis, the sensitivity and specificity was evaluated. In simulated clinical samples, the assay was able to detect 10² and 10³ leptospires/ml in spiked urine and blood samples, respectively. In experimentally infected animals, leptospiral DNA could be detected in blood and lung samples as early as Day 1 post infection. This assay was also shown to be stable and remained sensitive for up to five months at ambient temperature. Hence, this lyophilized reagent-based PCR assay with high specificity, sensitivity and stability would provide a simple, rapid and reliable method in diagnosing acute leptospirosis, especially in the field of veterinary medicine.
    Matched MeSH terms: Freeze Drying*
  15. Shofian NM, Hamid AA, Osman A, Saari N, Anwar F, Dek MS, et al.
    Int J Mol Sci, 2011;12(7):4678-92.
    PMID: 21845104 DOI: 10.3390/ijms12074678
    The effects of freeze-drying on antioxidant compounds and antioxidant activity of five tropical fruits, namely starfruit (Averrhoa carambola L.), mango (Mangifera indica L.), papaya (Carica papaya L.), muskmelon (Cucumis melo L.), and watermelon Citruluss lanatus (Thunb.) were investigated. Significant (p < 0.05) differences, for the amounts of total phenolic compounds (TPC), were found between the fresh and freeze-dried fruit samples, except muskmelon. There was no significant (p > 0.05) change, however, observed in the ascorbic acid content of the fresh and freeze-dried fruits. Similarly, freeze-drying did not exert any considerable effect on β-carotene concentration of fruits, except for mango and watermelon, where significantly (p < 0.05) higher levels were detected in the fresh samples. The results of DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging and reducing power assays revealed that fresh samples of starfruit and mango had relatively higher antioxidant activity. In case of linoleic acid peroxidation inhibition measurement, a significant (p < 0.05) but random variation was recorded between the fresh and freeze-dried fruits. Overall, in comparison to β-carotene and ascorbic acid, a good correlation was established between the result of TPC and antioxidant assays, indicating that phenolics might have been the dominant compounds contributing towards the antioxidant activity of the fruits tested.
    Matched MeSH terms: Freeze Drying
  16. Lan G, Abdullah N, Jalaludin S, Ho YW
    J Sci Food Agric, 2012 Jan 30;92(2):266-73.
    PMID: 21796639 DOI: 10.1002/jsfa.4570
    Phytate-bound phosphorus (P) in poultry diets is poorly available to chickens. Hence exogenous phytase is often added to their diets. Mitsuokella jalaludinii is a rumen bacterial species that produces high phytase activity. In this study the effects of freeze-dried active M. jalaludinii culture (FD-AMJC) and Natuphos(®) phytase (phytase N) supplementations on the growth performance and nutrient utilisation of broiler chickens fed a low-available P (aP) diet were evaluated.
    Matched MeSH terms: Freeze Drying
  17. Foo PC, Chan YY, See Too WC, Tan ZN, Wong WK, Lalitha P, et al.
    J Med Microbiol, 2012 Sep;61(Pt 9):1219-1225.
    PMID: 22556327 DOI: 10.1099/jmm.0.044552-0
    Entamoeba histolytica is the only Entamoeba species that causes amoebiasis in humans. Approximately 50 million people are infected, with 100, 000 deaths annually in endemic countries. Molecular diagnosis of Entamoeba histolytica is important to differentiate it from the morphologically identical Entamoeba dispar to avoid unnecessary medication. Conventional molecular diagnostic tests require trained personnel, cold-chain transportation and/or are storage-dependent, which make them user-unfriendly. The aim of this study was to develop a thermostabilized, one-step, nested, tetraplex PCR assay for the detection of Entamoeba histolytica, Entamoeba dispar and Entamoeba species in cold-chain-free and ready-to-use form. The PCR test was designed based on the Entamoeba small subunit rRNA (SSU-rRNA) gene, which detects the presence of any Entamoeba species, and simultaneously can be used to differentiate Entamoeba histolytica from Entamoeba dispar. In addition, a pair of primers was designed to serve as an internal amplification control to help identify inhibitors in the samples. All PCR reagents together with the designed primers were thermostabilized by lyophilization and were stable at 24 °C for at least 6 months. The limit of detection of the tetraplex PCR was found to be 39 pg DNA or 1000 cells for Entamoeba histolytica and 78 pg DNA or 1000 cells for Entamoeba dispar, and the specificity was 100 %. In conclusion, this cold-chain-free, thermostabilized, one-step, nested, multiplex PCR assay was found to be efficacious in differentiating Entamoeba histolytica from other non-pathogenic Entamoeba species.
    Matched MeSH terms: Freeze Drying
  18. Mehrnoush A, Mustafa S, Yazid AM
    Int J Mol Sci, 2012;13(3):2939-50.
    PMID: 22489134 DOI: 10.3390/ijms13032939
    Response surface methodology (RSM) along with central composite design (CCD) was applied to optimize the freeze drying conditions for purified pectinase from mango (Mangifera indica cv. Chokanan) peel. The effect of pectinase content (-2.66, 62.66 mg/mL), Arabic gum (-1.21, 10.21%, w/v), and maltodextrin (0.73, 7.26%, w/v) as independent variables on activity, yield, and storage stability of freeze-dried enzyme was evaluated. Storage stability of pectinase was investigated after one week at 4 °C and yield percentage of the enzyme after encapsulation was also determined. The independent variables had the most significant (p < 0.05) effect on pectinase activity and yield of the enzyme. It was observed that the interaction effect of Arabic gum and maltodextrin improved the enzymatic properties of freeze-dried pectinase. The optimal conditions for freeze-dried pectinase from mango peel were obtained using 30 mg/mL of pectinase content, 4.5 (%, w/v) of Arabic gum, and 4 (%, w/v) of maltodextrin. Under these conditions, the maximum activity (11.12 U/mL), yield (86.4%) and storage stability (84.2%) of encapsulated pectinase were achieved.
    Matched MeSH terms: Freeze Drying/methods*
  19. Mirhosseini H, Amid BT
    Chem Cent J, 2013 Jan 04;7(1):1.
    PMID: 23289739 DOI: 10.1186/1752-153X-7-1
    BACKGROUND: A natural carbohydrate biopolymer was extracted from the agricultural biomass waste (durian seed). Subsequently, the crude biopolymer was purified by using the saturated barium hydroxide to minimize the impurities. Finally, the effect of different drying techniques on the flow characteristics and functional properties of the purified biopolymer was investigated. The present study elucidated the main functional characteristics such as flow characteristics, water- and oil-holding capacity, solubility, and foaming capacity.

    RESULTS: In most cases except for oven drying, the bulk density decreased, thus increasing the porosity. This might be attributed to the increase in the inter-particle voids of smaller sized particles with larger contact surface areas per unit volume. The current study revealed that oven-dried gum and freeze-dried gum had the highest and lowest compressibility index, thus indicating the weakest and strongest flowability among all samples. In the present work, the freeze-dried gum showed the lowest angle of repose, bulk, tapped and true density. This indicates the highest porosity degree of freeze dried gum among dried seed gums. It also exhibited the highest solubility, and foaming capacity thus providing the most desirable functional properties and flow characteristics among all drying techniques.

    CONCLUSION: The present study revealed that freeze drying among all drying techniques provided the most desirable functional properties and flow characteristics for durian seed gum.

    Matched MeSH terms: Freeze Drying
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