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Vairimorpha imperfecta n.sp., a microsporidian exhibiting an abortive octosporous sporogony in Plutella xylostella L. (Lepidoptera: Yponomeutidae)

Canning EU, Curry A, Cheney S, Lafranchi-Tristem NJ, Haque MA

Parasitology, 1999 Sep;119 ( Pt 3):273-86.
PMID: 10503253

The microsporidian genus Nosema is characterized by development in direct control with host cell cytoplasm, diplokaryotic nuclei throughout development and disporous sporogony. The genus Vairimorpha exhibits the same features plus an octoporous sporogony producing uninucleate spores in a sporophorous vesicle. A microsporidium from diamondback moth, Plutella xylostella, falls between Nosema and Vairimorpha in that it initiates but fails to complete the octosporous sequence in this host. The name Vairimorpha imperfecta n.sp. is proposed. Merogony is mainly by formation of buds from multinucleate meronts, the buds remaining attached in chains. Diplokaryotic spores measure 4.3 x 2.0 microns (fresh) and have 15.5 coils of the polar tube in 1 rank. The octosporous sporogony is aborted owing to irregular formation of nuclear spindles, incomplete cytoplasmic fission and bizarre deposition of electron-dense episporontal secretions. Phylogenetic analyses of the sequences of the small subunit rRNA genes of V. imperfecta and of several Nosema and Vairimorpha spp. place V. imperfecta in a clade with Nosema spp. from Lepidoptera rather than in the clade containing the more typical species of Vairimorpha. It is suggested that the ancestors of the Vairimorpha/Nosema complex of species exhibited both disporous and octosporous sporogonies, as does the type species of Vairimorpha, Vairimorpha necatrix. It would follow that true Nosema spp. have lost the ability to express an octosporous sequence and that V. imperfecta is in the process of losing it. It is proposed that the genera Nosema and Vairimorpha be placed in the same family Nosematidae Labbé 1899, rather than in separate families and orders as at present.

Matched MeSH terms: Microscopy, Electron
Ultrastructural pathology of the upper respiratory tract of rabbits experimentally infected with Pasteurella multocida A:3

Al-Haddawi MH, Jasni S, Zamri-Saad M, Mutalib AR, Sheikh-Omar AR

Res Vet Sci, 1999 Oct;67(2):163-70.
PMID: 10502487

Twenty-four 8 to 9 week-old Pasteurella multocida -free rabbits were divided into three equal groups, the first group was pretreated with hydrocortisone and inoculated intranasally with pasteurella multocida serotype A:3. The second group was inoculated intranasally with P. multocida without hydrocortisone treatment. The third group was inoculated with phosphate buffered saline only and used as a control group. Pasteurella multocida was isolated from the nasal cavity of all infected rabbits in group 1 and 2 and from the trachea of seven rabbits in group 1 and five rabbits in group 2. This study was conducted to observe the ultrastructural changes of the upper respiratory tract of hydrocortisone treated and non-treated rabbits infected with P. multocida serotype A:3. The ultrastructural changes detected in infected rabbits were ciliary destruction and deciliation of the ciliated epithelial cells, cellular swelling, goblet cell hyperplasia and endothelial cell damage. Pasteurella multocida was observed attached to the degenerated cilia, microvilli and mucus. Pasteurella multocida infection was associated with inflammatory responses, which may have caused tissue damage. It is possible that hydrocortisone modulates the severity of infection as an immune suppressor and an inhibitor of goblet cell secretion.

Matched MeSH terms: Microscopy, Electron
Histopathology and cytopathology of white spot syndrome virus (WSSV) in cultured Penaeus monodon from peninsular Malaysia with emphasis on pathogenesis and the mechanism of white spot formation

Wang YG, Hassan MD, Shariff M, Zamri SM, Chen X

Dis Aquat Organ, 1999 Dec 22;39(1):1-11.
PMID: 11407399

Since 1994, white spot syndrome virus (WSSV) has been detected in cultured shrimp Penaeus monodon in Peninsular Malaysia. The gross signs, target organs and histo-cytopathology for the viral infection were studied and it was found to infect most organs and tissues including oocytes, but not hepatopancreatocytes and epithelial cells of the midgut, which were regarded as refractory tissues. Based on a time-sequence of ultrastructural cytopathology, 4 cytopathic profiles and 6 phases of viral morphogenesis were described. The virions were elliptical to short rods with trilamilar envelopes that measured 305 +/- 30 x 127 +/- 11 nm. Viral nucleosomes were often present singly in infected nuclei and were associated with the early stages of viral replication. The structure of WSSV pathognomonic white, cuticular lesions was examined at the microscopic and ultrastructural levels and the mechanism of their formation appeared to be related to the disruption of exudate transfer from epithelial cells to the cuticle via cuticular pore canals.

Matched MeSH terms: Microscopy, Electron
Mixed polymer coating for modified release from coated spheroids

Tan YT, Heng PW, Wan LS

Pharm Dev Technol, 1999;4(4):561-70.
PMID: 10578511

Modified-release drug spheroids coated with an aqueous mixture of high-viscosity hydroxypropylmethylcellulose (HPMC) and sodium carboxymethylcellulose (NaCMC) were formulated. The preparation of core drug spheroids and the coating procedures were performed using the rotary processor and a bottom-spray fluidized bed, respectively. Dissolution studies indicated that incorporation of suitable additives, such as poly(vinylpyrrolidone) (PVP) and poly(ethylene glycol) 400 (PEG) improved the flexibility and integrity of the coat layer by retarding the drug release. An increase in coating levels applied generally retarded the release rate of the drug. However, the ratio of HPMC to NaCMC in the mixed, plasticized polymeric coat played a more dominant role in determining the dissolution T50% values. The optimal ratio of HPMC to NaCMC for prolonged drug release was found to be 3:1, whereas an increase in the amount of NaCMC in the mixed polymer coat only increased drug release. The synergistic viscosity effect of HPMC and NaCMC in retarding drug release rate was greater in distilled water than in dissolution media of pH 1 and 7.2. Cross-sectional view of the scanning electron micrograph showed that all of the coated spheroids exhibited a well-fused, continuous, and distinct layer of coating film. The drug release kinetics followed a biexponential first-order kinetic model.

Matched MeSH terms: Microscopy, Electron, Scanning
Degumming of crude palm oil by membrane filtration

Ong KK, Fakhru'l-Razi A, Baharin BS, Hassan MA

Artif Cells Blood Substit Immobil Biotechnol, 1999 Sep-Nov;27(5-6):381-5.
PMID: 10595436

The application of membrane separation in palm oil refining process has potential for energy and cost savings. The conventional refining of crude palm oil results in loss of oil and a contaminated effluent. Degumming of crude palm oil by membrane technology is conducted in this study. The objective of this research is to study the feasibility of membrane filtration for the removal of phospholipids in the degumming of crude palm oil, including analyses of phosphorus content, carotene content free fatty acids (as palmitic acid), colour and volatile matter. A PCI membrane module was used which was equipped with polyethersulfone membranes having a molecular weight cut off of 9,000 (type ES209). In this study, phosphorus content was the most important parameter monitored. The membrane effectively removed phospholipids resulting in a permeate with a phosphorus content of less than 0.3 ppm The percentage removal of phosphorus was 96.4% and was considered as a good removal. Lovibond colour was reduced from 27R 50Y to 20R 30Y. The percentage removal of carotene was 15.8%. The removal of colour was considered good but the removal of carotene was considered insignificant by the membrane. Free fatty acids and volatile matter were not removed. Typical of membrane operations, the permeate flux decreased with time and must be improved in order to be adopted on an industrial scale. Membrane technology was found to have good potential in crude palm oil degumming. However, an appropriate method has to be developed to clean the membranes for reuse.

Matched MeSH terms: Microscopy, Electron, Scanning
Inadvertent expression of dengue 2 virus NS3-EGFP fusion protein in Escherlchla coll using the pEGFP-N 1 mammalian expression vector

Norazizah S, AbuBakar S

JUMMEC, 1999;4:41-46.

Dengue 2 New Guinea C (NGC) virus NS3 protein, a potentially important virulence factor was cloned to the N-terminus of the Aeqirorea victoria enhanced green fluorescent protein (EGFP) using the pEGFP-N1 mammalian expression vector. During amplification of the recombinant plasmid in E. coli, transformants expressing the EGFP were detected in vivo when viewed using fluorescence microscopy. This inadvertent expression of the recombinant fusion protein was confirmed further by detection of the T7.Tag peptide cloned to the aluino terminal of the fusion protein using T 7.Tag specific monoclonal antibody. These findings represent perhaps the first reported expression of the T7.Tag-NS3-EGFP fusion protein using the pEGFP-N1 mammalian expression vector in E. coli. KEYWORDS: Dengue, NS3, pEGFP-N1, fusion protein.

Matched MeSH terms: Microscopy
Sarcocystis levinei infection in Philippine water buffaloes (Bubalus bubalis)

Claveria FG, Cruz MJ

Parasitol Int, 2000 Jan;48(3):243-7.
PMID: 11227764

Ultrastructural studies of sarcocysts obtained from Philippine water buffaloes revealed the presence of the commonly reported macroscopic species, Sarcocystis fusiformis, and the microscopic species Sarcocystis levinei (Dissanaike A, Kan S. Studies on Sarcocystis in Malaysia. I: Sarcocystis levinei n.sp. from the water buffalo Bubalus bubalis. Z Parasitenkd 1978;55:127-38), (Huong L, Dubey J, Uggla A. Redescription of Sarcocystis levinei Dissanaike and Kan, 1978 (Protozoa: Sarcocystidae) of the water buffalo (Bubalus bubalis). J Parasitol 1997;83:1148-52). The globular to oval microscopic cysts commonly observed in the muscles of the diaphragm and neck exhibit compartmentalized arrangement of zoites with septal partitions and measure 13-48 microns in diameter. The parasitophorous vacuolar membrane of sarcocyst bears minute and hair-like villar protrusions measuring 2.3-2.75 microns long emanating at certain distances from the primary cyst wall and lack microfilaments. Villar protrusions have expanded to dome-shaped base measuring 0.33-1.6 microns long by 0.22-1.0 micron wide, and intermediate and tapering distal segments bent approximately 90 degrees and run parallel to the cyst surface. The distal segments at some areas join to form conical tufts. The primary cyst wall bears numerous prominent undulations that are arranged in small clusters. The ground substance is 0.42-0.57 micron thick. This paper documents the first report of S. levinei in Philippine water buffaloes possessing the type 7 cyst wall.

Matched MeSH terms: Microscopy, Electron/veterinary
Ultrastructural observation of nasal and pulmonary intracellular Pasteurella multocida A:3 in rabbits

Al-Haddawi MH, Jasni S, Zamri-Saad M, Mutalib AR, Son R, Sheikh-Omar AR

Vet Res Commun, 2000 Apr;24(3):153-67.
PMID: 10836274

Sixteen 8- to 9-week-old Pasteurella multocida-free rabbits were divided into two equal groups. Eight rabbits in one group were inoculated intranasally with P. multoida type A:3. The other eight were inoculated intranasally with phosphate-buffered saline and used as controls. Nasal swabs taken before and after inoculation were cultured for bacterial isolation. Post-mortem nasal swabs and lung samples were cultured for bacteriological isolation. Nasal mucosa and lung samples were collected and processed for transmission electron microscopy. Pasteurella multocida was isolated from the nasal cavity of all infected rabbits and from the lungs of four infected rabbits. Degenerative ultrastructural changes in epithelial cells and endothelial cells were seen in the infected rabbits. Deciliation of the ciliated epithelium and hyperplasia of the goblet cells in the nasal mucosa were noted. Thickening of the alveolar septa due to hyperplasia of type II pneumocytes, swelling of the endothelial lining of capillaries and infiltration of inflammatory cells were also observed. Intracellular invasion of the nasal epithelial cells and of type II pneumocytes by the organism was observed. Coccobacilli were observed in membrane-bound vacuoles in the cytoplasm of these cells. The vacuoles were adjacent to the host-cell mitochondria and some of these vacuoles appeared to be fused to the mitochondrial membrane. Some type I pneumocytes with intracellular membrane-bound vacuoles containing bacterial cells showed protrusions, which appeared to detach into the alveolar lumina. These results indicated that P. multocida serotype A:3 in rabbits can invade the epithelial cell and cause structural changes in the interstitium, epithelium and endothelium. Heterophils and macrophages appear to play important roles in tissue injury.

Matched MeSH terms: Microscopy, Electron/veterinary
In vitro study of Pasteurella multocida adhesion to trachea, lung and aorta of rabbits

Al-Haddawi MH, Jasni S, Zamri-Saad M, Mutalib AR, Zulkifli I, Son R, et al.

Vet J, 2000 May;159(3):274-81.
PMID: 10775473

In vitro experiments were undertaken to study the adhesion and colonization to tracheal mucosa, lung and aorta explants from freshly killed rabbits of two different strains of Pasteurella multocida. Serotype A:3 (capsulated, fimbriae +, haemagglutination -, dermonecrotic toxin -) isolated from a rabbit with rhinitis, and serotype D:1 (non-capsulated, fimbriae +, haemagglutination +, dermonecrotic toxin +) isolated from a dead rabbit with septicaemia, were used. When the explants were observed under the scanning electron microscope, the type D strain was highly adherent to trachea and aorta explants compared to the type A strain. Adhesion to lung explants was best achieved by the type A strain after 45 min incubation, but after 2 h incubation no significant difference was observed between the strains. Our data indicate that the presence of fimbriae and the absence of capsule seem to enhance the adherence of P. multocida type D strain to tracheal tissue. The capsular material of P. multocida type A strain and the toxin of the type D strain seem to influence the adherence to lung tissue in rabbit. Adhesion of strain D to aorta may indicate the expression of receptors on the endothelium to that strain and may also explain the ability of certain strains to cause septicaemia.

Matched MeSH terms: Microscopy, Electron, Scanning
A new bacterial white spot syndrome (BWSS) in cultured tiger shrimp Penaeus monodon and its comparison with white spot syndrome (WSS) caused by virus

Wang YG, Lee KL, Najiah M, Shariff M, Hassan MD

Dis Aquat Organ, 2000 May 25;41(1):9-18.
PMID: 10907134

This paper describes a new bacterial white spot syndrome (BWSS) in cultured tiger shrimp Penaeus monodon. The affected shrimp showed white spots similar to those caused by white spot syndrome virus (WSSV), but the shrimp remained active and grew normally without significant mortalities. The study revealed no evidence of WSSV infection using electron microscopy, histopathology and nested polymerase chain reaction. Electron microscopy indicated bacteria associated with white spot formation, and with degeneration and discoloration of the cuticle as a result of erosion of the epicuticle and underlying cuticular layers. Grossly the white spots in BWSS and WSS look similar but showed different profiles under wet mount microscopy. The bacterial white spots were lichen-like, having perforated centers unlike the melanized dots in WSSV-induced white spots. Bacteriological examination showed that the dominant isolate in the lesions was Bacillus subtilis. The occurrence of BWSS may be associated with the regular use of probiotics containing B. subtilis in shrimp ponds. The externally induced white spot lesions were localized at the integumental tissues, i.e., cuticle and epidermis, and connective tissues. Damage to the deeper tissues was limited. The BWS lesions are non-fatal in the absence of other complications and are usually shed through molting.

Matched MeSH terms: Microscopy, Electron; Microscopy, Electron, Scanning
Fulltext Nipah virus: a recently emergent deadly paramyxovirus

Chua KB, Bellini WJ, Rota PA, Harcourt BH, Tamin A, Lam SK, et al.

Science, 2000 May 26;288(5470):1432-5.
PMID: 10827955

A paramyxovirus virus termed Nipah virus has been identified as the etiologic agent of an outbreak of severe encephalitis in people with close contact exposure to pigs in Malaysia and Singapore. The outbreak was first noted in late September 1998 and by mid-June 1999, more than 265 encephalitis cases, including 105 deaths, had been reported in Malaysia, and 11 cases of encephalitis or respiratory illness with one death had been reported in Singapore. Electron microscopic, serologic, and genetic studies indicate that this virus belongs to the family Paramyxoviridae and is most closely related to the recently discovered Hendra virus. We suggest that these two viruses are representative of a new genus within the family Paramyxoviridae. Like Hendra virus, Nipah virus is unusual among the paramyxoviruses in its ability to infect and cause potentially fatal disease in a number of host species, including humans.

Matched MeSH terms: Microscopy, Electron
Diagnosis of nipah virus encephalitis by electron microscopy of cerebrospinal fluid

Chow VT, Tambyah PA, Yeo WM, Phoon MC, Howe J

J Clin Virol, 2000 Dec;19(3):143-7.
PMID: 11090749

BACKGROUND: between 1998 and 1999, an outbreak of potentially fatal viral encephalitis erupted among pig farm workers in West Malaysia, and later spread to Singapore where abattoir workers were afflicted. Although Japanese encephalitis virus was initially suspected, the predominant aetiologic agent was subsequently confirmed to be Nipah virus, a novel paramyxovirus related to but distinct from Hendra virus.
OBJECTIVE: to describe a case of Nipah virus encephalitis in a pig farm worker from Malaysia.
STUDY DESIGN: the clinical, laboratory and radiological findings of this patient were scrutinized. Special emphasis was placed on the electron microscopic analysis of the cerebrospinal fluid (CSF) specimen from this patient.
RESULTS: the neurological deficits indicative of cerebellar involvement were supported by the magnetic resonance imaging that showed prominent cerebellar and brainstem lesions. CSF examination provided further evidence of viral encephalitis. Complement fixation and/or RT-PCR assays were negative for Japanese encephalitis, herpes simplex, measles and mumps viruses. ELISA for detecting IgM and IgG antibodies against Hendra viral antigens were equivocal for the CSF specimen, and tested initially negative for the first serum sample but subsequently positive for the repeat serum sample. Transmission electron microscopy of negatively-stained preparations of CSF revealed enveloped virus-like structures fringed with surface projections as well as nucleocapsids with distinctive helical and herringbone patterns, features consistent with those of other paramyxoviruses, including Hendra virus.
CONCLUSION: this case report reiterates the relevant and feasible role of diagnostic electron microscopy for identifying and/or classifying novel or emerging viral pathogens for which sufficiently specific and sensitive tests are lacking.

Matched MeSH terms: Microscopy, Electron
Ultrastructural pathology of nasal and tracheal mucosa of rabbits experimentally infected with Pasteurella multocida serotype D:1

Al-Haddawi MH, Jasni S, Israf DA, Zamri-Saad M, Mutalib AR, Sheikh-Omar AR

Res Vet Sci, 2001 Jun;70(3):191-7.
PMID: 11676614

Sixteen 8- to 9-week-old Pasteurella multocida-free New Zealand White rabbits were divided into two equal groups. The first group was inoculated intranasally with P multocida serotype D:1 strain and the second group that was inoculated with phosphate-buffered saline (PBS) only was used as a control group. Pasteurella multocida was isolated from the nasal cavity of all infected rabbits in group 1 and from tracheal swabs of seven rabbits in this group. Four rabbits in group 1 died with clinical signs of septicaemia, two rabbits had mucopurulent nasal discharge and pneumonic lesions and the other two did not show any clinical signs or gross lesions. The ultrastructural changes detected were deciliation or clumping of cilia of ciliated epithelium, cellular swelling, vacuolation and sloughing. The subepithelial capillaries showed congestion, intravascular fibrin deposition, platelets aggregation and endothelial injury. Pasteurella multocida was observed attached to the injured endothelial cells. Heterophils, mast cells, vacuolated monocytes and macrophages infiltrated the lamina propria and between the degenerated epithelial cells.

Matched MeSH terms: Microscopy, Electron/veterinary
Keloids - the sebum hypothesis revisited

Fong EP, Bay BH

Med Hypotheses, 2002 Apr;58(4):264-9.
PMID: 12027517

The aetiology of the keloid scar has not been completely elucidated. Numerous hypotheses have been proposed in the past to explain the unusual characteristics of the keloid scar. While we do know that there is excessive and ongoing collagen-deposition, the exact triggering stimulus is a subject of conjecture. We present some of our photographic records of keloids and electron microscopic findings of keloid edges and reiterate the sebum hypothesis. We also attempt to explain the features of keloids in the light of the present knowledge of immunology and cell biology.

Matched MeSH terms: Microscopy, Electron
Inhibition of hepatitis B virus assembly with synthetic peptides derived from the viral surface and core antigens

Tan WS

J Gen Appl Microbiol, 2002 Apr;48(2):103-7.
PMID: 12469306

The long surface antigen (L-HBsAg) of hepatitis B virus (HBV) plays a central role in the production of infectious virions. During HBV morphogenesis, both the PreS and S domains of L-HBsAg form docking sites for the viral nucleocapsids. Thus, a compound that disrupts the interaction between the L-HBsAg and nucleocapsids could serve as a therapeutic agent against the virus based upon inhibition of morphogenesis. Synthetic peptides correspond to the binding sites in L-HBsAg inhibited the association of L-HBsAg with core antigen (HBcAg). A synthetic peptide carrying the epitope for a monoclonal antibody to the PreS1 domain competed weakly with L-HBsAg for HBcAg, but peptides corresponding to a linear sequence at the tip of the nucleocapsid spike did not, showing that the competing peptide does not resemble the tip of the spike.

Matched MeSH terms: Microscopy, Electron
Self-assembled nanocomposite of organic-inorganic hybrid: 2,4-dichlorophenoxyacetate in Zn-Al hydrotalcite-like layers

Hussein MZ, Mohd Amin JB, Zainal Z, Yahaya AH

J Nanosci Nanotechnol, 2002 Apr;2(2):143-6.
PMID: 12908300

Hydrotalcite-like inorganic layers of Zn-Al, a host containing an organic moiety, 2,4-dichlorophenoxy-acetate, as a guest, was prepared by the spontaneous self-assembly method from an aqueous solution for the formation of a new layered organic-inorganic hybrid nanocomposite material. In this synthesis, the host- and guest-forming species were simultaneously included in the mother liquor, aged, and separated. Various Zn/Al ratios (R = 2, 3, and 4), concentrations of 2,4-dichlorophenoxyacetic acid (0.03-0.1 M), and pH (7 and 10) were studied to optimize the formation of the layered nancomposite. It was found that the optimum conditions for the formation of the nanocomposite were R = 4, pH 7, and concentration of 2,4-dichlorophenoxyacetic acid = 0.08 M. X-ray diffraction shows that this sample affords a nanolayered structure with a basal spacing of 24.6 A.

Matched MeSH terms: Microscopy, Electron, Scanning
Iridovirus disease in two ornamental tropical freshwater fishes: African lampeye and dwarf gourami

Sudthongkong C, Miyata M, Miyazaki T

Dis Aquat Organ, 2002 Apr 5;48(3):163-73.
PMID: 12033703

Many species of ornamental freshwater fishes are imported into Japan from all over the world. We found African lampeye Aplocheilichthys normani and dwarf gourami Colisa lalia suffering from an iridovirus infection just after being imported by tropical fish wholesalers from Singapore. African lampeye were cultured on the Indonesian Island of Sumatra and dwarf gourami were cultured in Malaysia before export. Diseased fishes displayed distinct histopathological signs of iridovirus infection: systemic appearance of inclusion body-bearing cells, and necrosis of splenocytes and hematopoietic cells. Electron microscopy revealed viral particles (African lampeye:180 to 200 nm in edge to edge diameter; dwarf gourami: 140 to 150 nm in diameter) in an inclusion body within the cytoplasm of inclusion body-bearing cells as well as in the cytoplasm of necrotized cells. Experimental infection with an iridovirus isolate from African lampeye (ALIV) revealed pathogenicity of ALIV to African lampeye and pearl gourami Trichogaster leeri. Polymerase chain reaction (PCR) products from ALIV and an iridovirus isolate from dwarf gourami (DGIV) using iridovirus-specific primers were indistinguishable. The nucleotide sequence of PCR products derived from ALIV (696 base pairs) and DGIV (701 base pairs) had 95.3% identity. These results indicate that ALIV and DGIV have a single origin.

Matched MeSH terms: Microscopy, Electron/veterinary
Floral synomone of a wild orchid, Bulbophyllum cheiri, lures Bactrocera fruit flies for pollination

Tan KH, Nishida R, Toong YC

J Chem Ecol, 2002 Jun;28(6):1161-72.
PMID: 12184394 DOI: 10.1023/A:1016277500007

The major fruit fly attractant component in the floral fragrance of Bulbophyllum cheiri (fruit fly orchid) is methyl eugenol (ME). In the lowland rain forest of Malaysia, the solitary and nonresupinate flowers of the fruit fly orchid attract only males of the ME-sensitive fruit fly species (Bactrocera carambolae, B. papayae. and B. umbrosa. During the morning, the fruit fly orchid flower is visited by many fruit flies, which can sometimes cover the whole flower. The number of visitors dwindles in the afternoon. Headspace analysis of the flower shows a high ME peak in the morning, a small one between 12:00 and 14:00 hr, and no detectable ME peak after 14:00 hr. The process of pollination in the wild is initiated by attraction of fruit flies to floral ME. The flower, with the aid of its specialized hinged see-saw lip (labellum), temporarily traps (< 1 min) a fruit fly pollinator between its lip and column. Just prior to this, the fly is rewarded by the opportunity to feed on the floral attractant found on surfaces of petals, sepals, and lip. The pollinaria borne by two wild B. papayae males (caught on and near the fruit fly orchid flower) are identical in morphology and structure with those obtained from the flower. Many of the B. papayae males (17 of 22 analyzed) attracted to the fruit fly orchid already possessed both ME metabolites, trans-coniferyl alcohol and 2-allyl-4,5-dimethoxyphenol, in their rectal glands. indicating that they had previously consumed ME. In this orchid-fruit fly association, both organisms gain direct reproductive benefits: the orchid flower gets pollinated without having to offer nectar, while the fruit fly boosts its pheromone and defense system, as well as its sexual competitiveness by feeding on the ME produced by the flower.

Matched MeSH terms: Microscopy, Electron, Scanning
Isolation, identification and characterization of chicken anaemia virus in Malaysia

Chowdhury SM, Omar AR, Aini I, Hair-Bejo M, Jamaluddin AA, Kono Y, et al.

J. Biochem. Mol. Biol. Biophys., 2002 Aug;6(4):249-55.
PMID: 12186740

A study was conducted to isolate and identify chicken anaemia virus (CAV) from field samples of clinically infected broiler chickens in Malaysia. A total of 125 samples were collected from chickens aged 2-6 weeks with clinically depressed and retarded growth, of which five samples were found positive to CAV directly by polymerase chain reaction (PCR). Later, five isolates of CAV from the respective five PCR positive samples were isolated in MDCC-MSB1 cells at passage 4 based on cytopathic effects, PCR and indirect immunofluorescent antibody test. The isolates were identified as BL-1, BL-2, BL-3, BL-4 and BL-5. These CAV isolates were found to resist treatment with chloroform and heat at 37 degrees C for 2 h, 56 degrees C for 30 min and 70 degrees C for 5 min. One of the isolates, BL-5 produced significant reduction (p < 0.001) of hematocrit values (9-19%), pale bone marrow, thymus atrophy and haemorrhages in skin/muscle when inoculated into 1-day old SPF chickens. Restriction enzyme digestion of 926 bp genomic fragments of all the isolates including Cux-1 isolate with HindIII exhibited a similar pattern of bands in 2% agarose gel. The present findings confirmed the presence of CAV in Malaysia.

Matched MeSH terms: Microscopy, Fluorescence
Redescription of Serpinema octorugatum (Baylis, 1933) nematoda: Camallanidae from the Malayan box turtle Cuora amboinensis Daudin Chelonia: Bataguridae

Sharma RS, Rigby MC, Sumita S, Sani RA, Vidyadaran MK, Jasni S, et al.

Syst Parasitol, 2002 Sep;53(1):19-28.
PMID: 12378130

We redescribe the camallanid nematode Serpinema octorugatum (Baylis, 1933) from the box turtle Cuora amboinensis (Daudin) collected in Malaysia. In this redescription, we amend the original description by noting that there are only four cephalic papillae and that there are five pairs of post-anal papillae, and propose that the name of this species be corrected from S. octorugatus to S. octorugatum. Additionally, we removed the tissues overlying the buccal capsule and have used SEM studies to show that the peribuccal shields extend laterally from the buccal capsule, forming a surface possibly used in muscle attachment. Furthermore, we show that the supposedly non-cuticularised cylinder connecting the buccal capsule to the oesophagus in the Camallanidae is part of the buccal capsule and is, therefore, likely to be cuticularised. We also examine morphological measurements of taxonomic interest for correlations with total body length and find that many characters traditionally used for inter- and intra-specific comparisons are correlated with total body length in adult female worms. This suggests that comparisons between samples of adult female worms that do not account for the potential effect of total body length may be misleading. However, we show that some features of taxonomic interest are not correlated with total body length.

Matched MeSH terms: Microscopy, Electron, Scanning

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