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Background Spontaneous preterm birth (SPB) is a global public health concern with devastating health effects on SPB survivors. This study aimed to determine modifiable antenatal risk factors associated with SPB among women attending government healthcare facilities in Malaysia. Methodology A retrospective record review of 49,416 national obstetrics registry data from 2015 was conducted and analyzed using binary logistic regression based on six antenatal factor divisions. Results Mothers with pre-existing diabetes had higher odds (adjusted odds ratio (aOR) = 3.09) of delivering prematurely than mothers without diabetes. Mothers with chronic hypertension with superimposed pre-eclampsia (aOR = 2.51) and gestational hypertension (aOR = 1.44) had higher odds of experiencing preterm birth than mothers with no hypertension. Underweight mothers had higher odds (aOR = 1.27) of delivering prematurely than mothers with an ideal body mass index (18.5 to <25.0 kg/m2). Mothers with moderate anemia (hemoglobin level: 7 to <9 g/dL) had higher odds (aOR = 1.18) of preterm birth than mothers with normal hemoglobin levels (≥11 g/dL). Conclusions Maternal biomarkers, such as glucose level, blood pressure, BMI, and hemoglobin level, play an important role in reducing the rate of SPB in Malaysia. This study recommends strengthening pre-pregnancy, antenatal, and postpartum care through multidisciplinary and multi-agency team collaboration, addressing both modifiable and non-modifiable risk factors and adopting a dual approach that combines preventive and curative care.
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OBJECTIVE: To examine the contribution of preterm birth and size-for-gestational age in stillbirths using six 'newborn types'. DESIGN: Population-based multi-country analyses. SETTING: Births collected through routine data systems in 13 countries. SAMPLE: 125 419 255 total births from 22+0 to 44+6 weeks' gestation identified from 2000 to 2020. METHODS: We included 635 107 stillbirths from 22+0 weeks' gestation from 13 countries. We classified all births, including stillbirths, into six 'newborn types' based on gestational age information (preterm, PT, <37+0 weeks versus term, T, ≥37+0 weeks) and size-for-gestational age defined as small (SGA, <10th centile), appropriate (AGA, 10th-90th centiles) or large (LGA, >90th centile) for gestational age, according to the international newborn size for gestational age and sex INTERGROWTH-21st standards. MAIN OUTCOME MEASURES: Distribution of stillbirths, stillbirth rates and rate ratios according to six newborn types. RESULTS: 635 107 (0.5%) of the 125 419 255 total births resulted in stillbirth after 22+0 weeks. Most stillbirths (74.3%) were preterm. Around 21.2% were SGA types (PT + SGA [16.2%], PT + AGA [48.3%], T + SGA [5.0%]) and 14.1% were LGA types (PT + LGA [9.9%], T + LGA [4.2%]). The median rate ratio (RR) for stillbirth was highest in PT + SGA babies (RR 81.1, interquartile range [IQR], 68.8-118.8) followed by PT + AGA (RR 25.0, IQR, 20.0-34.3), PT + LGA (RR 25.9, IQR, 13.8-28.7) and T + SGA (RR 5.6, IQR, 5.1-6.0) compared with T + AGA. Stillbirth rate ratios were similar for T + LGA versus T + AGA (RR 0.7, IQR, 0.7-1.1). At the population level, 25% of stillbirths were attributable to small-for-gestational-age. CONCLUSIONS: In these high-quality data from high/middle income countries, almost three-quarters of stillbirths were born preterm and a fifth small-for-gestational age, with the highest stillbirth rates associated with the coexistence of preterm and SGA. Further analyses are needed to better understand patterns of gestation-specific risk in these populations, as well as patterns in lower-income contexts, especially those with higher rates of intrapartum stillbirth and SGA.
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OBJECTIVE: To examine the prevalence of novel newborn types among 165 million live births in 23 countries from 2000 to 2021. DESIGN: Population-based, multi-country analysis. SETTING: National data systems in 23 middle- and high-income countries. POPULATION: Liveborn infants. METHODS: Country teams with high-quality data were invited to be part of the Vulnerable Newborn Measurement Collaboration. We classified live births by six newborn types based on gestational age information (preterm <37 weeks versus term ≥37 weeks) and size for gestational age defined as small (SGA, <10th centile), appropriate (10th-90th centiles), or large (LGA, >90th centile) for gestational age, according to INTERGROWTH-21st standards. We considered small newborn types of any combination of preterm or SGA, and term + LGA was considered large. Time trends were analysed using 3-year moving averages for small and large types. MAIN OUTCOME MEASURES: Prevalence of six newborn types. RESULTS: We analysed 165 017 419 live births and the median prevalence of small types was 11.7% - highest in Malaysia (26%) and Qatar (15.7%). Overall, 18.1% of newborns were large (term + LGA) and was highest in Estonia 28.8% and Denmark 25.9%. Time trends of small and large infants were relatively stable in most countries. CONCLUSIONS: The distribution of newborn types varies across the 23 middle- and high-income countries. Small newborn types were highest in west Asian countries and large types were highest in Europe. To better understand the global patterns of these novel newborn types, more information is needed, especially from low- and middle-income countries.
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Antimicrobial peptides (AMPs), the self-defence products of organisms, are extensively distributed in plants. They can be classified into several groups, including thionins, defensins, snakins, lipid transfer proteins, glycine-rich proteins, cyclotides and hevein-type proteins. AMPs can be extracted and isolated from different plants and plant organs such as stems, roots, seeds, flowers and leaves. They perform various physiological defensive mechanisms to eliminate viruses, bacteria, fungi and parasites, and so could be used as therapeutic and preservative agents. Research on AMPs has sought to obtain more detailed and reliable information regarding the selection of suitable plant sources and the use of appropriate isolation and purification techniques, as well as examining the mode of action of these peptides. Well-established AMP purification techniques currently used include salt precipitation methods, absorption-desorption, a combination of ion-exchange and reversed-phase C18 solid phase extraction, reversed-phase high-performance liquid chromatography (RP-HPLC), and the sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) method. Beyond these traditional methods, this review aims to highlight new and different approaches to the selection, characterisation, isolation, purification, mode of action and bioactivity assessment of a range of AMPs collected from plant sources. The information gathered will be helpful in the search for novel AMPs distributed in the plant kingdom, as well as providing future directions for the further investigation of AMPs for possible use on humans.
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Peptídeos Catiônicos Antimicrobianos/isolamento & purificação , Plantas/química , Peptídeos Catiônicos Antimicrobianos/química , Cromatografia Líquida de Alta Pressão , Eletroforese em Gel de PoliacrilamidaRESUMO
The sharp increase in incidence of dengue infection has necessitated the development of methods for the rapid diagnosis of this deadly disease. Here we report the design and development of a reliable, sensitive, and specific optical immunosensor for the detection of the dengue nonstructural protein 1 (NS1) biomarker in clinical samples obtained during early stages of infection. The present optical NS1 immunosensor comprises a biosensing surface consisting of specific monoclonal NS1 antibody for immunofluorescence-based NS1 antigen determination using fluorescein isothiocyanate (FITC) conjugated to IgG antibody. The linear range of the optical immunosensor was from 15-500ngmL-1, with coefficient of determination (R2) of 0.92, high reproducibility (the relative standard deviation obtained was 2%), good stability for 21days at 4°C, and low detection limit (LOD) at 15ngmL-1. Furthermore, the optical immunosensor was capable of detecting NS1 analytes in plasma specimens from patients infected with the dengue virus, with low cross-reaction with plasma specimens containing the Japanese encephalitis virus (JEV) and Zika virus. No studies have been performed on the reproducibility and cross-reactivity regarding NS1 specificity, which is thus a limitation for optical NS1 immunosensors. In contrast, the present study addressed these limitations carefully where these two important experiments were conducted to showcase the robustness of our newly developed optical-based fluorescence immunosensor, which can be practically used for direct NS1 determination in any untreated clinical sample.
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Técnicas Biossensoriais/métodos , Vírus da Dengue/imunologia , Dengue/diagnóstico , Proteínas não Estruturais Virais/isolamento & purificação , Anticorpos Monoclonais/imunologia , Biomarcadores/análise , Reações Cruzadas/imunologia , Dengue/sangue , Dengue/virologia , Vírus da Dengue/isolamento & purificação , Vírus da Encefalite Japonesa (Espécie)/imunologia , Vírus da Encefalite Japonesa (Espécie)/isolamento & purificação , Encefalite Japonesa/sangue , Encefalite Japonesa/virologia , Imunofluorescência/métodos , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Proteínas não Estruturais Virais/sangue , Proteínas não Estruturais Virais/imunologia , Zika virus/imunologia , Zika virus/isolamento & purificação , Infecção por Zika virus/sangue , Infecção por Zika virus/virologiaRESUMO
BACKGROUND: Currently, several assays can diagnose acute dengue infection. However, none of these assays can predict the severity of the disease. Biomarkers that predicts the likelihood that a dengue patient will develop a severe form of the disease could permit more efficient patient triage and allows better supportive care for the individual in need, especially during dengue outbreaks. METHODS: We measured 20 plasma markers i.e. IFN-γ, IL-10, granzyme-B, CX3CL1, IP-10, RANTES, CXCL8, CXCL6, VCAM, ICAM, VEGF, HGF, sCD25, IL-18, LBP, sCD14, sCD163, MIF, MCP-1 and MIP-1ß in 141 dengue patients in over 230 specimens and correlate the levels of these plasma markers with the development of dengue without warning signs (DWS-), dengue with warning signs (DWS+) and severe dengue (SD). RESULTS: Our results show that the elevation of plasma levels of IL-18 at both febrile and defervescence phase was significantly associated with DWS+ and SD; whilst increase of sCD14 and LBP at febrile phase were associated with severity of dengue disease. By using receiver operating characteristic (ROC) analysis, the IL-18, LBP and sCD14 were significantly predicted the development of more severe form of dengue disease (DWS+/SD) (AUC = 0.768, P < 0.0001; AUC = 0.819, P < 0.0001 and AUC = 0.647, P = 0.014 respectively). Furthermore, we also found that the levels of VEGF were directly correlated and sCD14 was inversely correlated with platelet count, suggesting that the endothelial activation and microbial translocation may played a role in pathogenesis of dengue disease. CONCLUSIONS: Given that the elevation IL-18, LBP and sCD14 among patients with severe form of dengue disease, our findings suggest a pathogenic role for an aberrant inflammasome and monocyte activation in the development of severe form of dengue disease.
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Dengue/sangue , Dengue/imunologia , Monócitos/citologia , Dengue Grave/sangue , Dengue Grave/imunologia , Proteínas de Fase Aguda , Adulto , Área Sob a Curva , Biomarcadores/sangue , Proteínas de Transporte/sangue , Citocinas/metabolismo , Dengue/diagnóstico , Vírus da Dengue , Surtos de Doenças , Feminino , Humanos , Inflamassomos , Inflamação , Interleucina-18/sangue , Receptores de Lipopolissacarídeos/sangue , Estudos Longitudinais , Masculino , Glicoproteínas de Membrana/sangue , Contagem de Plaquetas , Curva ROC , Dengue Grave/diagnóstico , Adulto JovemRESUMO
BACKGROUND: The neonatal Apgar score at 5 min has been found to be a better predictor of outcomes than the Apgar score at 1 min. A baby, however, must pass through the first minute of life to reach the fifth. There has been no research looking at predictors of recovery (Apgar scores ≥7) by 5 min in neonates with 1 min Apgar scores <4. METHODS: An analysis of observational data was conducted using live, singleton, term births recorded in the Malaysian National Obstetrics Registry between 2010 and 2012. A total of 272,472 live, singleton, term births without congential anomalies were recorded, of which 1,580 (0.59%) had 1 min Apgar scores <4. Descriptive methods and bi- and multi-variable logistic regression were used to identify risk factors associated with recovery (5 min Apgar score ≥7) from 1 min Apgar scores <4. RESULTS: Less than 1% of births have a 1 min Apgar scores <4. Only 29.4% of neonates with 1 min Apgar scores <4 recover to a 5 min Apgar score ≥7. Among uncomplicated vaginal deliveries, after controlling for other factors, deliveries by a doctor of neonates with a 1 min Apgar score <4 had odds of recovery 2.4 times greater than deliveries of neonates with a 1 min Apgar score <4 by a nurse-midwife. Among deliveries of neonates with a 1 min Apgar score <4 by doctors, after controlling for other factors, planned and unplanned CS was associated with better odds of recovery than uncomplicated vaginal deliveries. Recovery was also associated with maternal obesity, and there was some ethnic variation - in the adjusted analysis indigenous (Orang Asal) Malaysians had lower odds of recovery. CONCLUSIONS: A 1 min Apgar score <4 is relatively rare, and less than a third recover by five minutes. In those newborns the qualification of the person performing the delivery and the type of delivery are independent predictors of recovery as is maternal BMI and ethnicity. These are associations only, not necessarily causes, and they point to potential areas of research into health systems factors in the labour room, as well as possible biological and cultural factors.
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Índice de Apgar , Cesárea/estatística & dados numéricos , Enfermeiros Obstétricos/estatística & dados numéricos , Obesidade/epidemiologia , Obstetrícia , Médicos/estatística & dados numéricos , Complicações na Gravidez/epidemiologia , Sistema de Registros , Parto Obstétrico/estatística & dados numéricos , Procedimentos Cirúrgicos Eletivos/estatística & dados numéricos , Emergências , Feminino , Humanos , Recém-Nascido , Malásia/epidemiologia , Gravidez , Fatores de Risco , Nascimento a TermoRESUMO
Influenza viruses belong to the family Orthomyxoviridae of enveloped viruses and are an important cause of respiratory infections worldwide. The influenza virus is able to infect a wide variety species as diverse as poultry, marine, pigs, horses, and humans. Upon infection with influenza virus the innate immunity plays a critical role in efficient and rapid control of viral infections as well as in adaptive immunity initiation. The humoral immune system produces antibodies against different influenza antigens, of which the HA-specific antibody is the most important for neutralization of the virus and thus prevention of illness. Cell mediated immunity including CD4+ helper T cells and CD8+ cytotoxic T cells are the other arms of adaptive immunity induced upon influenza virus infection. The complex inherited factors and age related changes are associated with the host immune responses. Here, we review the different components of immune responses against influenza virus. Additionally, the correlation of the immune response to age and inherited factors has been discussed. These determinations lead to a better understanding of the limitations of immune responses for developing improved vaccines to control influenza virus infection.
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Chemotherapies remain far from ideal due to drug resistance; therefore, novel chemotherapeutic agents with higher effectiveness are crucial. The extracts of four Phyllanthus species, namely Phyllanthus niruri, Phyllanthus urinaria, Phyllanthus watsonii, and Phyllanthus amarus, were shown to induce apoptosis and inhibit metastasis of breast carcinoma cells (MCF-7). The main objective of this study was to determine the pathways utilized by these four Phyllanthus species to exert anti-metastatic activities. A cancer 10-pathway reporter was used to investigate the pathways affected by the four Phyllanthus species. Results indicated that these Phyllanthus species suppressed breast carcinoma metastasis and proliferation by suppressing matrix metalloprotein 2 and 9 expression via inhibition of the extracellular signal-related kinase (ERK) pathway. Additionally, inhibition of hypoxia-inducible factor 1-α in the hypoxia pathway caused reduced vascular endothelial growth factor and inducible nitric oxide synthase expression, resulting in anti-angiogenic effects and eventually anti-metastasis. Two-dimensional gel electrophoresis identified numerous proteins suppressed by these Phyllanthus species, including invasion proteins, anti-apoptotic protein, protein-synthesis proteins, angiogenic and mobility proteins, and various glycolytic enzymes. Our results indicated that ERK and hypoxia pathways are the most likely targets of the four Phyllanthus species for the inhibition of MCF-7 metastasis.
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Neoplasias da Mama , Hipóxia Celular , Humanos , Sistema de Sinalização das MAP Quinases , Células MCF-7 , Phyllanthus , Extratos Vegetais , Fator A de Crescimento do Endotélio VascularRESUMO
In the title compound, C14H15N3O2, one of the methyl C atoms of the tert-butyl group lies almost in the plane of the chromene ring system [deviation = -0.097â (2)â Å], one lies above and one lies below [deviations = 1.460â (3) and 1.006â (3)â Å, respectively]. The C-C-N-N torsion angle is 142.33â (17)°. In the crystal, moelcules are linked by weak C-Hâ¯O hydrogen bonds to generate C(6) chains propagating in the [010] direction.
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In the title mol-ecule, C13H13N3O2, the benzo-pyran ring system is essentially planar, with a maximum deviation of 0.017â (1)â Å. In the crystal, weak C-Hâ¯O hydrogen bonds link mol-ecules into ladders along [010]. In addition, π-π inter-actions between inversion-related mol-ecules, with centroid-centroid distances in the range 3.679â (2)-3.876â (2)â Å, complete a two-dimensional network parallel to (001).
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The role of T-cell immunosenescence and functional CD8(+) T-cell responses in HIV/TB co-infection is unclear. We examined and correlated surrogate markers of HIV disease progression with immune activation, immunosenescence and differentiation using T-cell pools of HIV/TB co-infected, HIV-infected and healthy controls. Our investigations showed increased plasma viremia and reduced CD4/CD8 T-cell ratio in HIV/TB co-infected subjects relative to HIV-infected, and also a closer association with changes in the expression of CD38, a cyclic ADP ribose hydrolase and CD57, which were consistently expressed on late-senescent CD8(+) T cells. Up-regulation of CD57 and CD38 were directly proportional to lack of co-stimulatory markers on CD8(+) T cells, besides diminished expression of CD127 (IL-7Rα) on CD57(+)CD4(+) T cells. Notably, intracellular IFN-γ, perforin and granzyme B levels in HIV-specific CD8(+) T cells of HIV/TB co-infected subjects were diminished. Intracellular CD57 levels in HIV gag p24-specific CD8(+) T cells were significantly increased in HIV/TB co-infection. We suggest that HIV-TB co-infection contributes to senescence associated with chronic immune activation, which could be due to functional insufficiency of CD8(+) T cells.
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Linfócitos T CD8-Positivos/imunologia , Senescência Celular/imunologia , Infecções por HIV/imunologia , Imunossenescência/imunologia , Tuberculose Pulmonar/imunologia , ADP-Ribosil Ciclase 1/biossíntese , Adulto , Relação CD4-CD8 , Antígenos CD57/biossíntese , Antígenos CD57/metabolismo , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/patologia , Diferenciação Celular/imunologia , Proliferação de Células , Coinfecção/imunologia , Progressão da Doença , Feminino , Granzimas/metabolismo , Cadeias alfa de HLA-DR/imunologia , Humanos , Interferon gama/metabolismo , Subunidade alfa de Receptor de Interleucina-7/biossíntese , Ativação Linfocitária/imunologia , Masculino , Glicoproteínas de Membrana/biossíntese , Perforina/metabolismoRESUMO
Oxalate toxicity is mediated through generation of reactive oxygen species (ROS) via a process that is partly dependent on mitochondrial dysfunction. Here, we investigated whether C-phycocyanin (CP) could protect against oxidative stress-mediated intracellular damage triggered by oxalate in MDCK cells. DCFDA, a fluorescence-based probe and hexanoyl-lysine adduct (HEL), an oxidative stress marker were used to investigate the effect of CP on oxalate-induced ROS production and membrane lipid peroxidation (LPO). The role of CP against oxalate-induced oxidative stress was studied by the evaluation of mitochondrial membrane potential by JC1 fluorescein staining, quantification of ATP synthesis and stress-induced MAP kinases (JNK/SAPK and ERK1/2). Our results revealed that oxalate-induced cells show markedly increased ROS levels and HEL protein expression that were significantly decreased following pre-treatment with CP. Further, JC1 staining showed that CP pre-treatment conferred significant protection from mitochondrial membrane permeability and increased ATP production in CP-treated cells than oxalate-alone-treated cells. In addition, CP treated cells significantly decreased the expression of phosphorylated JNK/SAPK and ERK1/2 as compared to oxalate-alone-treated cells. We concluded that CP could be used as a potential free radical-scavenging therapeutic strategy against oxidative stress-associated diseases including urolithiasis.
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Citoproteção/efeitos dos fármacos , Mitocôndrias/patologia , Oxalatos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Ficocianina/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Cães , Ativação Enzimática/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Células Madin Darby de Rim Canino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Substâncias Protetoras/farmacologia , Espécies Reativas de Oxigênio/metabolismoRESUMO
BACKGROUND: Rapid and early dengue diagnosis is essential for patient management and early disease intervention. MP Diagnostics ASSURE(®) Dengue IgA Rapid Test (Dengue IgA RT) was developed for the rapid detection of anti-dengue IgA in patients' biological samples. The performance of Dengue IgA RT was examined using multiple categories of well-characterized samples. MATERIALS AND METHODS: Dengue IgA RT was designed and developed. Following characterization of samples by reference ELISAs, the performance of the kit was evaluated. RESULTS: The overall sensitivity and specificity of Dengue IgA RT were 86.70% (n=233) and 86.05% (n=681) respectively; in which Dengue IgA RT detected 77.42% primary and 92.86% secondary cases; compared to 70.97% and 72.14% by IgM-Cap ELISA and 89.25% and 20% by Non-Structural Protein 1 (NS1) Ag ELISA respectively. Using 125 paired samples, Dengue IgA RT showed 84.80% sensitivity at acute phase and 99.20% sensitivity at convalescent phase; with 92% specificity at both phases. Dengue IgA RT also demonstrated a consistent performance (sensitivity: 85.53%, specificity: 80%) with 76 whole blood samples. In detecting all four serotypes of DENV (n=162), the performance of Dengue IgA RT was comparable with in-house IgM-Cap ELISA. Kinetics of anti-dengue IgA production was elucidated with 42.86% detection level as early as one-two days after fever onset, which increased to 83.33% between five and seven days after fever onset. CONCLUSION: Dengue IgA RT demonstrated a good performance and is applicable as one of the dengue early diagnostic tools at all levels of health care system.
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Anti-dengue virus immunoglobulin M kits were evaluated. Test sensitivities were 21%-99% and specificities were 77%-98% compared with reference ELISAs. False-positive results were found for patients with malaria or past dengue infections. Three ELISAs showing strong agreement with reference ELISAs will be included in the World Health Organization Bulk Procurement Scheme.
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Anticorpos Antivirais/sangue , Vírus da Dengue/imunologia , Dengue/diagnóstico , Imunoglobulina M/sangue , Kit de Reagentes para Diagnóstico , Dengue/virologia , Ensaio de Imunoadsorção Enzimática , Reações Falso-Positivas , Humanos , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Tioman virus (TioPV) and Menangle virus (MenPV) are two antigenically and genetically related paramyxoviruses (genus: Rubulavirus, family: Paramyxoviridae) isolated from Peninsular Malaysia (2001) and Australia (1997), respectively. Both viruses are potential zoonotic agents. In the present study, the infectivity, growth kinetics, morphology and morphogenesis of these two paramyxoviruses in a human neuronal cell (SK-N-SH) line were investigated. Sub-confluent SK-N-SH cells were infected with TioPV and MenPV at similar multiplicity of infection. These cells were examined by conventional and immunoelectron microscopy, and virus titres in the supernatants were assayed. Syncytia were observed for both infections in SK-N-SH cells and were more pronounced during the early stages of TioPV infection. The TioPV titre increased consistently (10(1)) every 12 h after infection. In MenPV-infected cells, cellular material was frequently observed within budding virions, and microfilaments and microtubules were abundant. Viral budding was common, and extracellular MenPVs tended to be more pleomorphic compared to TioPVs, which appeared to be more spherical in appearance. The MenPV cytoplasmic viral inclusion appeared to be comparatively smaller, loose and interspersed with randomly scattered circle-like particles, whereas huge tubule-like cytoplasmic inclusions were observed in TioPV-infected cells. Both viruses also displayed different cellular pathology in the SK-N-SH cells. The intracellular ultrastructural characteristics of these two viruses in infected neuronal cells may allow them to be differentiated by electron microscopy.