Zahirrah Begam Mohamed Rasheed
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Previous Organizations / Institutes
The organizations / institutes from the scholar's other articles in the past ten years
Research Subjects
Zahirrah Begam Mohamed Rasheed has a total of 64 co-authors. Here are the top co-authors by number of shared publications:
- Lynne Sykes
Imperial College London
2 shared publications - Ahmad Shuhud Irfani Zakaria
Discipline of Paediatric Dentistry, Department of Family Oral Health, Faculty of Dentistry, National University of Malaysia, Kuala Lumpur, Malaysia
1 shared publication - Alison E. P. Ho
St. Mary’s Hospital, Imperial College Healthcare NHS Trust, London W2 1NY, UK
1 shared publication - Carolyn Gabriel
St. Mary’s Hospital, Imperial College Healthcare NHS Trust, London W2 1NY, UK
1 shared publication - Charlotte Frise
Queen Charlotte's and Chelsea Hospital, London, UK
1 shared publication - Chew Wei Sheng
Department of Family Oral Health, Faculty of Dentistry, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, Kuala Lumpur 50300, Malaysia
1 shared publication
Latest Publications
- Open Access
Evaluating the Erosive Effects of Freshly Squeezed Local Fruit Juices on Human Dental Enamel and Consumption Patterns Among Malaysian Adults
Background: The increasing popularity of fruit juices as part of perceived healthy dietary choices has raised concerns regarding their erosive effects on dental enamel. While prior in vitro studies have largely relied on commercial fruit drinks and non-human enamel samples, this study adopts a more ecologically valid approach by using fresh local fruit juices and extracted human teeth to evaluate enamel erosion. Objectives: This study aimed to assess the consumption patterns, oral hygiene behaviours, and awareness of the erosive potential of fruit juices among Malaysian adults and to evaluate the erosive effects of freshly squeezed local fruit juices on human dental enamel under simulated oral conditions. Methods: A questionnaire-based cross-sectional survey (n = 189) was conducted among dental clinic attendees to assess fruit juice intake habits, oral health practices, and awareness levels. In parallel, an in vitro study was performed using 40 extracted premolar teeth immersed in lime juice, pineapple juice, citric acid (positive control), or distilled water (negative control) over a 10-day period. Enamel volume loss, surface roughness, and microhardness were analysed pre- and post-immersion. Results: Fruit juice consumption was highly prevalent, with lime (57.7%) being the most commonly consumed, followed by watermelon (53.0%), star fruit (15.9%), and pineapple (15.4%). The majority of respondents preferred sweetened juices (75.7%) and demonstrated only moderate oral hygiene, with just 53.4% reporting brushing their teeth twice daily. Awareness of the dental effects of acidic beverages was limited. In vitro results confirmed that both lime and pineapple juices significantly reduced enamel microhardness and increased surface roughness (p < 0.0001), with lime juice causing the greatest enamel volume loss due to its higher acidity. Conclusions: These findings highlight the need for public health strategies that raise awareness on the implications of dietary acids and promote protective oral health behaviours. Dental practitioners should incorporate dietary counselling in routine care, particularly for populations at higher risk.
Open AccessEvaluating the Erosive Effects of Freshly Squeezed Local Fruit Juices on Human Dental Enamel and Consumption Patterns Among Malaysian Adults
Background: The increasing popularity of fruit juices as part of perceived healthy dietary choices has raised concerns regarding their erosive effects on dental enamel. While prior in vitro studies have largely relied on commercial fruit drinks and non-human enamel samples, this study adopts a more ecologically valid approach by using fresh local fruit juices and extracted human teeth to evaluate enamel erosion. Objectives: This study aimed to assess the consumption patterns, oral hygiene behaviours, and awareness of the erosive potential of fruit juices among Malaysian adults and to evaluate the erosive effects of freshly squeezed local fruit juices on human dental enamel under simulated oral conditions. Methods: A questionnaire-based cross-sectional survey (n = 189) was conducted among dental clinic attendees to assess fruit juice intake habits, oral health practices, and awareness levels. In parallel, an in vitro study was performed using 40 extracted premolar teeth immersed in lime juice, pineapple juice, citric acid (positive control), or distilled water (negative control) over a 10-day period. Enamel volume loss, surface roughness, and microhardness were analysed pre- and post-immersion. Results: Fruit juice consumption was highly prevalent, with lime (57.7%) being the most commonly consumed, followed by watermelon (53.0%), star fruit (15.9%), and pineapple (15.4%). The majority of respondents preferred sweetened juices (75.7%) and demonstrated only moderate oral hygiene, with just 53.4% reporting brushing their teeth twice daily. Awareness of the dental effects of acidic beverages was limited. In vitro results confirmed that both lime and pineapple juices significantly reduced enamel microhardness and increased surface roughness (p < 0.0001), with lime juice causing the greatest enamel volume loss due to its higher acidity. Conclusions: These findings highlight the need for public health strategies that raise awareness on the implications of dietary acids and promote protective oral health behaviours. Dental practitioners should incorporate dietary counselling in routine care, particularly for populations at higher risk.
- Open Access
Oral Microbiome Dynamics in Treated Childhood Caries: A Comparative Study
Background: Dental caries is a multifactorial disease that results from interactions of susceptible host, cariogenic microorganisms, and fermentable carbohydrate sources. Our study explored oral microbiome shifts in children before and after dental treatment. Methods: Initial saliva samples were collected from caries free, moderate caries, and severe caries children based on the decayed, missing, and filled teeth index (DMFT/dmft) index. After three months of dental treatment, second saliva samples were gathered from the moderate and severe caries groups. The microbiota was analyzed by 16S rRNA gene-based high-throughput sequencing. Results: Most children with caries were between seven and eight years of age (40%), from middle-income group families (61%), highly educated parents (18% secondary level and 75% tertiary level) with good oral hygiene practices. There was a significant increase in alpha-diversity post-dental intervention. Firmicutes, Bacteroidota, and Proteobacteria were abundant across all samples. Post-treatment, Actinobacteria, and Firmicutes significantly decreased (p < 0.05) while Fusobacteria, Proteobacteria, Spirochaetota, and Synergistota significantly increased (p < 0.05). At genus level, a decreased trend was seen in Streptococcus, Prevotella_7, and Rothia and an increased trend was seen in Fusobacterium, Neisseria, Haemophilus, and Leptotrichia, but was not statistically significant. Conclusions: This study on Malaysian children highlights that dental caries are influenced by factors like age, socioeconomic status, and diet, with oral microbiome diversity increasing post-treatment, though some harmful bacteria persist, indicating a need for targeted oral health education and further research on probiotics’ role in caries prevention.
Open AccessOral Microbiome Dynamics in Treated Childhood Caries: A Comparative Study
Background: Dental caries is a multifactorial disease that results from interactions of susceptible host, cariogenic microorganisms, and fermentable carbohydrate sources. Our study explored oral microbiome shifts in children before and after dental treatment. Methods: Initial saliva samples were collected from caries free, moderate caries, and severe caries children based on the decayed, missing, and filled teeth index (DMFT/dmft) index. After three months of dental treatment, second saliva samples were gathered from the moderate and severe caries groups. The microbiota was analyzed by 16S rRNA gene-based high-throughput sequencing. Results: Most children with caries were between seven and eight years of age (40%), from middle-income group families (61%), highly educated parents (18% secondary level and 75% tertiary level) with good oral hygiene practices. There was a significant increase in alpha-diversity post-dental intervention. Firmicutes, Bacteroidota, and Proteobacteria were abundant across all samples. Post-treatment, Actinobacteria, and Firmicutes significantly decreased (p < 0.05) while Fusobacteria, Proteobacteria, Spirochaetota, and Synergistota significantly increased (p < 0.05). At genus level, a decreased trend was seen in Streptococcus, Prevotella_7, and Rothia and an increased trend was seen in Fusobacterium, Neisseria, Haemophilus, and Leptotrichia, but was not statistically significant. Conclusions: This study on Malaysian children highlights that dental caries are influenced by factors like age, socioeconomic status, and diet, with oral microbiome diversity increasing post-treatment, though some harmful bacteria persist, indicating a need for targeted oral health education and further research on probiotics’ role in caries prevention.
- Open Access
Autologous Human Mesenchymal Stem Cell-Based Therapy in Infertility: New Strategies and Future Perspectives
Infertility could be associated with a few factors including problems with physical and mental health, hormonal imbalances, lifestyles, and genetic factors. Given that there is a concern about the rise of infertility globally, increased focus has been given to its treatment for the last several decades. Traditional assisted reproductive technology (ART) has been the prime option for many years in solving various cases of infertility; however, it contains significant risks and does not solve the fundamental problem of infertility such as genetic disorders. Attention toward the utilization of MSCs has been widely regarded as a promising option in the development of stem-cell-based infertility treatments. This narrative review briefly presents the challenges in the current ART treatment of infertility and the various potential applications of autologous MSCs in the treatment of these reproductive diseases.
Open AccessAutologous Human Mesenchymal Stem Cell-Based Therapy in Infertility: New Strategies and Future Perspectives
Infertility could be associated with a few factors including problems with physical and mental health, hormonal imbalances, lifestyles, and genetic factors. Given that there is a concern about the rise of infertility globally, increased focus has been given to its treatment for the last several decades. Traditional assisted reproductive technology (ART) has been the prime option for many years in solving various cases of infertility; however, it contains significant risks and does not solve the fundamental problem of infertility such as genetic disorders. Attention toward the utilization of MSCs has been widely regarded as a promising option in the development of stem-cell-based infertility treatments. This narrative review briefly presents the challenges in the current ART treatment of infertility and the various potential applications of autologous MSCs in the treatment of these reproductive diseases.
- Open Access
- 3 November 2022
- Published by Elsevier in International Journal of Infectious Diseases
- Vol. 125, 216-226
SARS-CoV-2 genomic surveillance in Malaysia: displacement of B.1.617.2 with AY lineages as the dominant Delta variants and the introduction of Omicron during the fourth epidemic wave
- 3 November 2022
- Published by Elsevier in International Journal of Infectious Diseases
- Vol. 125, 216-226
Open AccessSARS-CoV-2 genomic surveillance in Malaysia: displacement of B.1.617.2 with AY lineages as the dominant Delta variants and the introduction of Omicron during the fourth epidemic wave
- Open Access
Rhombencephalitis in Pregnancy—A Challenging Case of Probable Listeria Infection
Rhombencephalitis refers to inflammation of the brainstem and cerebellum, and can be caused by infections, autoimmune disorders or paraneoplastic syndromes. The most common infective cause is the bacterium Listeria monocytogenes. Listeria monocytogenes is the predominant species to cause human listeriosis, and is commonly due to the ingestion of contaminated foods. Symptoms include a mild gastroenteritis, fever (often with extreme temperature variations), headache, and myalgia. In more severe cases, invasive disease may lead to bacteraemia and neurolisteriosis. Pregnant women are more susceptible to listeriosis, which is believed to be due to pregnancy-related immune modulation. Maternal-neonatal infection with adverse pregnancy outcomes include neonatal listeriosis, spontaneous miscarriage and intrauterine fetal demise. Diagnosis may be challenging due to initial nonspecific symptoms and low sensitivity and specificity of confirmatory diagnostic laboratory tests. Here, we describe a case of rhombencephalitis in pregnancy, attributed to Listeria, and review the clinical features, diagnosis and multidisciplinary management. Lastly, we describe the immunological response to Listeria monocytogenes and show in vitro pro-inflammatory effects of Listeria monocytogenes on peripheral blood mononuclear cells and placental explants.
Open AccessRhombencephalitis in Pregnancy—A Challenging Case of Probable Listeria Infection
Rhombencephalitis refers to inflammation of the brainstem and cerebellum, and can be caused by infections, autoimmune disorders or paraneoplastic syndromes. The most common infective cause is the bacterium Listeria monocytogenes. Listeria monocytogenes is the predominant species to cause human listeriosis, and is commonly due to the ingestion of contaminated foods. Symptoms include a mild gastroenteritis, fever (often with extreme temperature variations), headache, and myalgia. In more severe cases, invasive disease may lead to bacteraemia and neurolisteriosis. Pregnant women are more susceptible to listeriosis, which is believed to be due to pregnancy-related immune modulation. Maternal-neonatal infection with adverse pregnancy outcomes include neonatal listeriosis, spontaneous miscarriage and intrauterine fetal demise. Diagnosis may be challenging due to initial nonspecific symptoms and low sensitivity and specificity of confirmatory diagnostic laboratory tests. Here, we describe a case of rhombencephalitis in pregnancy, attributed to Listeria, and review the clinical features, diagnosis and multidisciplinary management. Lastly, we describe the immunological response to Listeria monocytogenes and show in vitro pro-inflammatory effects of Listeria monocytogenes on peripheral blood mononuclear cells and placental explants.
- Open Access
- 3 November 2015
- Published by Wiley in Immunology
- Vol. 146 (4) , 630-644
Sulfasalazine augments a pro‐inflammatory response in interleukin‐1β‐stimulated amniocytes and myocytes
Summary: Preterm birth occurs in 10% of pregnancies and is a major cause of neonatal morbidity and mortality. The majority of cases of early preterm labour are associated with infection/inflammation, which places the fetal central nervous system at risk. Targeting immune activation is therefore an appealing therapeutic strategy for the prevention of preterm labour and neonatal brain injury. The expression of many labour‐associated and inflammatory‐response genes is controlled by the transcription factors nuclear factor‐κB (NF‐κB) and activator protein‐1 (AP‐1), which makes them therapeutic targets of interest. Sulfasalazine (SASP) has been shown to inhibit NF‐κB and reduce lipopolysaccharide‐induced cytokine concentrations in fetal membrane explants and reduce the rate of Escherichia coli‐induced preterm labour in mice. Its effects upon AP‐1 in the context of pregnancy are unknown. In this study the effect of SASP on interleukin‐1β (IL‐1β) ‐induced NF‐κB and AP‐1 activity, cytokine production and cyclo‐oxygenase‐2 (COX‐2) expression was examined in amniocytes and myocytes. A supra‐therapeutic concentration (5 mm) was required to inhibit IL‐1β‐induced NF‐κB (P < 0·0001) in amniocytes and IL‐1β‐induced NF‐κB (P < 0·01), AP‐1 (P < 0·01) and COX‐2 (P < 0·05) in myocytes. Despite inhibiting IL‐1β‐induced cytokines, a basal increase in IL‐6 (P < 0·01), IL‐8 (P < 0·0001) and tumour necrosis factor‐α (TNF‐α) (P < 0·001) was seen with 5 mm SASP in amniocytes, and significant cytotoxic effects were seen in myocytes. The therapeutic concentration of 0·015 mm had no inhibitory effects on pro‐inflammatory mediators, but led to an augmented response to IL‐1β‐induced IL‐6 (P < 0·01), IL‐8 (P < 0·05) and TNF‐α (P < 0·05) in amniocytes and IL‐8 (P < 0·05) in myocytes. SASP is therefore an unlikely therapeutic candidate for the prevention of inflammation‐induced preterm labour.
- 3 November 2015
- Published by Wiley in Immunology
- Vol. 146 (4) , 630-644
Open AccessSulfasalazine augments a pro‐inflammatory response in interleukin‐1β‐stimulated amniocytes and myocytes
Summary: Preterm birth occurs in 10% of pregnancies and is a major cause of neonatal morbidity and mortality. The majority of cases of early preterm labour are associated with infection/inflammation, which places the fetal central nervous system at risk. Targeting immune activation is therefore an appealing therapeutic strategy for the prevention of preterm labour and neonatal brain injury. The expression of many labour‐associated and inflammatory‐response genes is controlled by the transcription factors nuclear factor‐κB (NF‐κB) and activator protein‐1 (AP‐1), which makes them therapeutic targets of interest. Sulfasalazine (SASP) has been shown to inhibit NF‐κB and reduce lipopolysaccharide‐induced cytokine concentrations in fetal membrane explants and reduce the rate of Escherichia coli‐induced preterm labour in mice. Its effects upon AP‐1 in the context of pregnancy are unknown. In this study the effect of SASP on interleukin‐1β (IL‐1β) ‐induced NF‐κB and AP‐1 activity, cytokine production and cyclo‐oxygenase‐2 (COX‐2) expression was examined in amniocytes and myocytes. A supra‐therapeutic concentration (5 mm) was required to inhibit IL‐1β‐induced NF‐κB (P < 0·0001) in amniocytes and IL‐1β‐induced NF‐κB (P < 0·01), AP‐1 (P < 0·01) and COX‐2 (P < 0·05) in myocytes. Despite inhibiting IL‐1β‐induced cytokines, a basal increase in IL‐6 (P < 0·01), IL‐8 (P < 0·0001) and tumour necrosis factor‐α (TNF‐α) (P < 0·001) was seen with 5 mm SASP in amniocytes, and significant cytotoxic effects were seen in myocytes. The therapeutic concentration of 0·015 mm had no inhibitory effects on pro‐inflammatory mediators, but led to an augmented response to IL‐1β‐induced IL‐6 (P < 0·01), IL‐8 (P < 0·05) and TNF‐α (P < 0·05) in amniocytes and IL‐8 (P < 0·05) in myocytes. SASP is therefore an unlikely therapeutic candidate for the prevention of inflammation‐induced preterm labour.