MyMedR

Diagnostic Challenge in Veterinary Pathology: Metastatic Mammary Tumor in a Female Tiger (Panthera Tigris)

Fraser C, Keong Kok M, Shameha Abdul Razak I, Puspitasari Y, Salleh A

Vet Pathol, 2024 Jan 21.

PMID: 38247139 DOI: 10.1177/03009858241226650

Scale-up synthesis of lipase-catalyzed palm esters in stirred-tank reactor

Keng PS, Basri M, Ariff AB, Abdul Rahman MB, Abdul Rahman RN, Salleh AB

Bioresour Technol, 2008 Sep;99(14):6097-104.

PMID: 18243690 DOI: 10.1016/j.biortech.2007.12.049

Lipase-catalyzed production of palm esters by alcoholysis of palm oil with oleyl alcohol in n-hexane was performed in 2L stirred-tank reactor (STR). Investigation on the performance of reactor operation was carried out in batch mode STR with single impeller mounted on the centrally located shaft. Rushton turbine (RT) impellers provide the highest reaction yield (95.8%) at lower agitation speed as compared to AL-hydrofoil (AL-H) and 2-bladed elephant ear (EE) impellers. Homogenous enzyme particles suspension was obtained at 250 rpm by using RT impeller. At higher impeller speed, the shear effect on the enzyme particles caused by agitation has decreased the reaction performance. Palm esters reaction mixture in STR follows Newtons' law due to the linear relation between the shear stress (tau) and shear rate (dupsilon/dy). High stability of Lipozyme RM IM was observed as shown by its ability to be repeatedly used to give high percentage yield (79%) of palm esters even after 15 cycles of reaction. The process was successfully scale-up to 75 L STR (50 L working volume) based on a constant impeller tip speed approach, which gave the yield of 97.2% after 5h reaction time.

Lipase immobilized on poly(VP-co-HEMA) hydrogel for esterification reaction

Basri M, Samsudin S, Ahmad MB, Razak CN, Salleh AB

Appl Biochem Biotechnol, 1999 Sep;81(3):205-17.

PMID: 15304777

Lipase from Candida rugosa was immobilized by entrapment on poly(N-vinyl- 2-pyrrolidone-co-2-hydroxyethyl methacrylate) (poly[VP-co-HEMA]) hydrogel, and divinylbenzene was the crosslinking agent. The immobilized enzymes were used in the esterification reaction of oleic acid and butanol in hexane. The activities of the immobilized enzymes and the leaching ability of the enzyme from the support with respect to the different compositions of the hydrogels were investigated. The thermal, solvent, and storage stability of the immobilized lipases was also determined. Increasing the percentage of composition of VP from 0 to 90, which corresponds to the increase in the hydrophilicity of the hydrogels, increased the activity of the immobilized enzyme. Lipase immobilized on VP(%):HEMA(%) 90:10 exhibited the highest activity. Lipase immobilized on VP(%):HEMA(%) 50:50 showed the highest thermal, solvent, storage, and operational stability compared to lipase immobilized on other compositions of hydrogels as well as the native lipase.

Immobilization of hydrophobic lipase derivatives on to organic polymer beads

Basri M, Ampon K, Yunus WM, Razak CN, Salleh AB

J Chem Technol Biotechnol, 1994 Jan;59(1):37-44.

PMID: 7764496

A simple and effective method of lipase immobilization is described. Lipase from Candida rugosa was first modified with several hydrophobic modifiers before being adsorbed on to organic polymer beads. The soluble hydrophobic lipase derivatives adsorbed more strongly on to the various polymers as compared with the native lipase. The optimal adsorption temperature of the native and modified lipases on all the polymers was 40 degrees C. The optimal pH of adsorption was between 6 and 7. Lipase immobilized in this manner produced high catalytic recoveries which are affected by the type of modifiers, degree of modification and type of supports used. Monomethoxypolyethylene glycol (1900) activated with p-nitrophenyl chloroformate was found to be the best modifier of the enzyme at 95% modification, for adsorption to the polymers. Increasing the degree of modification of the enzyme increased the activity which was immobilized. Generally, both native and hydrophobic lipase derivatives showed higher specific activities when immobilized on polar polymers compared with non-polar polymers.

Water activity effect on lipase immobilized onto different compositions of poly(HEMA-MMA)

Esa NM, Yunus WM, Ahmad MB, Basri M, Razak CN, Salleh AB

Ann N Y Acad Sci, 1998 Dec 13;864:489-92.

PMID: 9928130

Development of an ELISA for detection of parathion, carbofuran, and 2,4-dichlorophenoxyacetic acid in water, soil, vegetables, and fruits

Razak CN, Salam F, Ampon K, Basri M, Salleh AB

Ann N Y Acad Sci, 1998 Dec 13;864:479-84.

PMID: 9928128

Effect of reductive alkylation of Candida rugosa lipase on its enantioselective esterification reaction

Basri M, Th'ng BL, Razak CN, Salleh AB

Ann N Y Acad Sci, 1998 Dec 13;864:192-7.

PMID: 9928091

Lipase-catalyzed esterification of palm-based 9,10-dihydroxystearic acid and 1-octanol in hexane--a kinetic study

Awang R, Basri M, Ahmad S, Salleh AB

Biotechnol Lett, 2004 Jan;26(1):11-4.

PMID: 15005144

The esterification of palm-based 9,10-dihydroxystearic acid (DHSA) and 1-octanol in hexane as catalyzed by lipase from Rhizomucor meihei (Lipozyme IM) followed Michaelis-Menten kinetics. The esterification reaction follows a Ping-Pong, Bi-Bi mechanism. The maximum rate was estimated to be 1 micromol min(-1) mg(-1) catalyst in hexane at 50 degrees C, and the Michaelis-Menten constants for DHSA and 1-octanol were 1.3 M and 0.7 M, respectively.

Determinants of breastfeeding duration in Peninsular Malaysia

Awang H, Salleh AL

Asia Pac J Public Health, 2000;12(2):102-6.

PMID: 11836918

The health benefits of breastfeeding to infants and mothers have been well recognised. This study applies linear regression analysis to assess the determinants of breastfeeding duration of first born using data from the Second Malaysian Family Life Survey. The proportion of women who breastfed their first child is 82 percent, of which 97 percent reported their breastfeeding duration. The distribution of breastfeeding duration has a mean of 5.7 months and a median of two months. Important determinants of breastfeeding duration include maternal age, ethnicity, period of first birth, husband's occupation and work status of the woman.

Human health risk of polycyclic aromatic hydrocarbons from consumption of blood cockle and exposure to contaminated sediments and water along the Klang Strait, Malaysia

Tavakoly Sany SB, Hashim R, Rezayi M, Salleh A, Rahman MA, Safari O, et al.

Mar Pollut Bull, 2014 Jul 15;84(1-2):268-79.

PMID: 24855978 DOI: 10.1016/j.marpolbul.2014.05.004

The concentration of carcinogenic poly aromatic hydrocarbons (c-PAHs) present in water and sediment of Klang Strait as well as in the edible tissue of blood cockle (Anadara granosa) was investigated. The human health risk of c-PAHs was assessed in accordance with the standards of the United States Environmental Protection Agency (US EPA). The cancer risks of c-PAHs to human are expected to occur through the consumption of blood cockles or via gastrointestinal exposure to polluted sediments and water in Kalng Strait. The non-carcinogenic risks that are associated with multiple pathways based on ingestion rate and contact rates with water were higher than the US EPA safe level at almost all stations, but the non-carcinogenic risks for eating blood cockle was below the level of US EPA concern. A high correlation between concentrations of c-PAHs in different matrices showed that the bioaccumulation of c-PAHs by blood cockles could be regarded as a potential health hazard for the consumers.

Fulltext Two variants of uterine leiomyoma in Malaysia's last Sumatran rhinoceros (Dicerorhinus sumatrensis)

Salleh A, Zainuddin ZZ, Mohamed Tarmizi MR, Yap KC, Zamri-Saad M

Vet Q, 2020 Dec;40(1):250-257.

PMID: 33045934 DOI: 10.1080/01652176.2020.1836431

Following its capture in March 2014, an adult female Sumatran rhinoceros frequently showed profuse vaginal bleeding. An ultrasonography suggested the presence of multiple reproductive lesions, including two uterine masses which were suspected to be leiomyomas. Soon after, an open pyometra was confirmed. Later in November 2019, the patient died and necropsy confirmed the presence of two uterine masses; one was located at the cervico-uterine junction and another in the uterine body, with pyometra, and cystic endometrial hyerplasia. Based on histological, special stains, and immunohistochemical examination, it was shown that one of the masses was composed of large, ovoid and polyhedral neoplastic mesenchymal cells with eosinophilic cytoplasm and a few binucleated cells surrounded by collagen fibres. It was tested positive for SMA and vimentin, while negative for desmin, cytokeratin AE1/AE3, EMA, CD34, and S100. The other mass was composed of mesenchymal cells undergoing myxoid degeneration as evidenced by the presence of glycosaminoglycan-rich matrix. It was tested positive for SMA, vimentin, partially positive for desmin, and negative for the other markers. With the aid of human medical nomenclature, these masses were diagnosed as epithelioid leiomyoma and myxoid leiomyoma, respectively. This report provides a clinical presentation, and histologic descriptions of the two variants of leiomyomas that have not been reported in veterinary medicine.

Fulltext Ultrastructural changes in endothelial cells of buffaloes following in-vitro exposure to Pasteurella multocida B:2

Puspitasari Y, Salleh A, Zamri-Saad M

BMC Vet Res, 2020 Jun 09;16(1):186.

PMID: 32517749 DOI: 10.1186/s12917-020-02415-2

BACKGROUND: Pasteurella multocida B:2 causes haemorrhagic septicaemia in cattle and buffaloes. However, buffaloes are found to be more susceptible to the infection than cattle. Upon infection, the pathogen rapidly spread from the respiratory tract to the blood circulation within 16-72 h, causing septicaemia. So far, limited study has been conducted to evaluate the response of endothelial cells of buffalo towards P. multocida B:2 and its lipopolysaccharide (LPS). This study aimed to evaluate the ultrastructural changes in the aortic endothelium of buffaloes (BAEC) following exposure to P. multocida B:2 and its endotoxin. The endothelial cells were harvested from the aorta of healthy buffaloes and were prepared as monolayer cell cultures. The cultures were divided into 3 groups before Group 1 was inoculated with 107 cfu/ml of whole cell P. multocida B:2, Group 2 with LPS, which was extracted earlier from 107 cfu/ml of P. multocida B:2 and Group 3 with sterile cell culture medium. The cells were harvested at 0, 6, 12, 18, 24, 36, and 48 h post-inoculation for assessment of cellular changes using transmission electron microscopy.

RESULTS: The BAEC of Groups 1 and 2 demonstrated moderate to severe endothelial lysis, suggestive of acute cellular injury. In general, severity of the ultrastructural changes increased with the time of incubation but no significant difference (p > 0.05) in the severity of the cellular changes between Groups 1 and 2 was observed in the first 18 h. The severity of lesions became significant (p

Fulltext Dentinogenic Ghost Cell Tumor in a Sumatran Rhinoceros

Salleh A, Zainuddin ZZ, Tarmizi RMM, Yap CK, Jeng CR, Zamri-Saad M

Animals (Basel), 2021 Apr 20;11(4).

PMID: 33923894 DOI: 10.3390/ani11041173

An adult female Sumatran rhinoceros was observed with a swelling in the left infraorbital region in March 2017. The swelling rapidly grew into a mass. A radiograph revealed a cystic radiolucent area in the left maxilla. In June 2017, the rhinoceros was euthanized. At necropsy, the infraorbital mass measured 21 cm × 30 cm. Samples of the infraorbital mass, left parotid gland, and left masseter muscle were collected for histopathology (Hematoxylin & Eosin, Von Kossa, Masson's trichrome, cytokeratin AE1/AE3, EMA, p53, and S-100). Numerous neoplastic epithelial cells showing pleomorphism and infiltration were observed. Islands of dentinoid material containing ghost cells and keratin pearls were observed with the aid of the two special histochemistry stains. Mitotic figures were rarely observed. All the neoplastic odontogenic cells and keratin pearls showed an intense positive stain for cytokeratin AE1/AE3, while some keratin pearls showed mild positive stains for S-100. All samples were negative for p53 and S-100 immunodetection. The mass was diagnosed as a dentinogenic ghost cell tumor.

Fulltext Pathological changes, distribution and detection of Brucella melitensis in foetuses of experimentally-infected does

Mazlan M, Khairani-Bejo S, Hamzah H, Nasruddin NS, Salleh A, Zamri-Saad M

Vet Q, 2021 Dec;41(1):36-49.

PMID: 33349157 DOI: 10.1080/01652176.2020.1867328

BACKGROUND: Brucellosis of goats is caused by Brucella melitensis. It is a re-emerging zoonotic disease in many countries due to transmission from domestic animals and wildlife such as ibex, deer and wild buffaloes.

OBJECTIVE: To describe the pathological changes, identification and distribution of B. melitensis in foetuses of experimentally infected does.

METHODS: Twelve female goats of approximately 90 days pregnant were divided into 4 groups. Group 1 was exposed intra-conjunctival to 100 µL of sterile PBS while goats of Groups 2, 3 and 4 were similarly exposed to 100 µL of an inoculum containing 109 CFU/mL of live B. melitensis. Goats of these groups were killed at 15, 30 and 60 days post-inoculation, respectively. Foetal fluid and tissues were collected for bacterial identification (using direct bacterial culture, PCR and immuno-peroxidase staining) and histopathological examination.

RESULTS: Bilateral intra-conjunctival exposure of pregnant does resulted in in-utero infection of the foetuses. All full-term foetuses of group 4 were either aborted or stillborn, showing petechiations of the skin or absence of hair coat with subcutaneous oedema. The internal organs showed most severe lesions. Immune-peroxidase staining revealed antigen distribution in all organs that became most extensive in group 4. Brucella melitensis was successfully isolated from the stomach content, foetal fluid and various other organs.

CONCLUSION: Vertical transmission of caprine brucellosis was evident causing mild to moderate lesions in different organs. The samples of choice for isolation and identification of B. melitensis are stomach content as well as liver and spleen tissue.

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