Recombinant subunit ORF2.1 antigen and induction of antibody against immunodominant epitopes in the hepatitis E virus capsid protein

A recombinant subunit antigen (ORF2.1), representing the carboxy-terminal 267 amino acids of the 660-amino-acid hepatitis E virus (HEV) capsid protein, was expressed in Escherichia coli and used for the immunisation of rats. Purified antigen formulated with either Aluminium Hydroxide Gel Adjuvant (Alum) or Titermax gave high and equivalent levels of antibody after three doses. Responses to two doses of 15, 75, or 150 microg antigen, formulated with Alum and given at 0 and 4 weeks, were also equivalent by 17 weeks after immunisation. Rats initially developed antibody to a wide range of linear epitopes in the ORF2.1 region, but by 27 weeks the predominant response detected by Western immunoblotting was restricted to the conformational epitope unique to ORF2.1 [Li et al. (1997) Journal of Medical Virology 52:289-300], a pattern that was also observed when comparing acute-phase patient serum samples with serum samples from convalescing patients. Antibody from immunised rats blocked the majority of patients' serum reactivity in enzyme-linked immunosorbent assay against both ORF2.1 (57-92% inhibition) and virus-like particles of HEV produced using the baculovirus system (74-97% inhibition). Together, these results suggest that the ORF2.1 subunit vaccine induces an antibody response against immunodominant, conformational epitopes in the viral capsid, which largely mimics that seen in convalescent patients, who are presumed to be immune to HEV infection.     

Immunoglobulins in saliva of preterm and full-term infants

The aim of this longitudinal study was to determine salivary levels of total IgA, IgG and IgM in 84 preterm and 214 full-term infants, from birth to 18 months of age. Unstimulated whole saliva was collected from each infant at birth, and subsequently at 3-monthly intervals. Immunoglobulin levels were estimated using an ELISA technique. At birth, IgA was detected in 147/214 (69%) full-term infants but only 47/84 (56%) preterm infants (P < 0.01). In the case of IgG, 61% of full-term and 56% of preterm infants showed detectable levels, whereas IgM was found in 71% and 73%, respectively. Levels of IgA and IgG rose from birth to 18 months, whereas IgM levels did not change significantly. Increases in salivary levels of IgA were associated with introduction of solid foods (P < 0.001), as well as tooth eruption (P < 0.001). Our results indicate that the majority of full-term and preterm infants are orally immunocompetent at birth.     

A study of primary dental enamel from preterm and full-term children using light and scanning electron microscopy

PURPOSE: The aim of this study was to examine the enamel thickness of the maxillary primary incisors of preterm children with very low birth weight (< 1,500 g) compared to full-term children with normal birth weight. METHODS: A total of 90 exfoliated maxillary primary central incisors were investigated using light microscopy and scanning electron microscopy (SEM). Three serial buccolingual ground sections of each tooth were examined under light microscopy, and maximum dimensions of the prenatally and postnatally formed enamel were measured. RESULTS: The enamel of preterm teeth was approximately 20% thinner than that for full-term teeth. Most of the reduction was observed in the prenatally formed enamel. This was 5 to 13 times thinner than that for full-term children (P<.001). The "catch-up" thickness of postnatally formed enamel did not compensate fully for the decrease in prenatal enamel (P<.001). Although none of the teeth used in this study had enamel defects visible to the naked eye, 52% of preterm teeth showed enamel hypoplasia under SEM, compared with only 16% found on full-term teeth (P<.001). These defects were present as pits or irregular, shallow areas of missing enamel. CONCLUSIONS: Preterm primary dental enamel is abnormal in surface quality, and is significantly thinner compared to full-term enamel. The thinner enamel is due mainly to reduced prenatal growth and results in smaller dimensions of the primary dentition.     

Palmoplantar hyperkeratosis with short stature, facial dysmorphism, and hypodontia--a new syndrome?: case report

In this study, a possible new syndrome affecting 18 members of a family spanning 4 generations is described. The main features include palmoplantar hyperkeratosis, proportionate short stature, facial dysmorphism, clinodactyly, epilepsy, deafness, and hypodontia. This syndrome is inherited in an autosomal dominant manner with a high degree of penetrance but variable expressivity. This syndrome differs markedly from the autosomal recessive types of palmoplantar hyperkeratosis such as Papillon-Lefèvre syndrome which shows premature loss of both dentitions. It is also distinct from other previously described cases of autosomal dominant forms of palmoplantar hyperkeratosis such as the Unna-Thost syndrome in that it presents short stature, facial dysmorphism, and hypodontia. These features which previously have not been associated with palmoplantar hyperkeratosis suggest that this may be a new syndrome.     

Rutin improves endotoxin‐induced acute lung injury via inhibition of iNOS and VCAM‐1 expression

Endotoxins exist anywhere including in water pools, dust, humidifier systems, and machining fluids. The major causal factor is endotoxins in many serious diseases, such as fever, sepsis, multi‐organ failure, meningococcemia, and severe morbidities like neurologic disability, or hearing loss. Endotoxins are also called lipopolysaccharide (LPS) and are important pathogens of acute lung injury (ALI). Rutin has potential beneficial effects including anti‐inflammation, antioxidation, anti‐hyperlipidemia, and anti‐platelet aggregation. Pre‐treatment with rutin inhibited LPS‐induced neutrophil infiltration in the lungs. LPS‐induced expression of vascular cell adhesion molecule (VCAM)‐1 and inducible nitric oxide synthase (iNOS) was suppressed by rutin, but there was no influence on expression of intercellular adhesion molecule‐1 and cyclooxygenase‐2. In addition, activation of the nuclear factor (NF)κB was reduced by rutin. Furthermore, we found that the inhibitory concentration of rutin on expression of VCAM‐1 and iNOS was similar to NFκB activation. In conclusion, rutin is a potential protective agent for ALI via inhibition of neutrophil infiltration, expression of VCAM‐1 and iNOS, and NFκB activation. © 2014 Wiley Periodicals, Inc. Environ Toxicol 31: 185–191, 2016.     

Involvement of L‐type Ca2+ channel and toll‐like receptor‐4 in nickel‐induced interleukin‐8 gene expression

The metal nickel (Ni²⁺) is found everywhere in our daily lives, including coins, costume jewelry, and even nuts and chocolates. Nickel poisoning can cause inflammatory reactions, respiratory diseases, and allergic contact dermatitis. To clarify the mechanism by which nickel induces mediators of inflammation, we used the human acute monocytic leukemia THP‐1 cell line as a model. Interleukin (IL)‐8 promoter activity as well as gene expression were tested by luciferase assay and real‐time polymerase chain reaction. The underlying mechanisms of nickel‐induced IL‐8 were investigated. We found that nickel induced IL‐8 gene expression via the L‐type Ca²⁺ channel, Toll‐like receptor‐4 (TRL‐4) and nuclear factor NF‐κB signal transduction pathways. Nickel activated NF‐κB expression through extracellular signal‐regulated kinase 1/2 phosphorylation and then increased IL‐8 expression. Thus, the L‐type Ca²⁺ channel and TRL‐4 play important roles in nickel‐induced inflammatory gene expressions. © 2014 Wiley Periodicals, Inc. Environ Toxicol 31: 5–12, 2016.     

Cell viability of acute myeloid leukaemia blasts in culture correlates with treatment outcome

Despite the advances in understanding the pathophysiology of acute myeloid leukaemia (AML), the cure rate for acute myeloid leukaemia patients remains low. Cytogenetic abnormalities and age are the prognostic factors that guide treatment decisions. However, many AML patients still die. The biological factors that influence treatment outcome are largely unknown. Thus, the objective of our study was to use the in vitro viability test to correlate with treatment outcome. Acute myeloid leukaemia blasts demonstrated differing ability to survive in culture. Our examination of blast phenotype at various days in culture showed two possible growth directions. First, cells underwent maturation by increased expression of CD16 and down-regulated CD34 (a haemopoietic stem cell marker). These cells also appeared to have undergone apoptosis. Alternatively, cells continued to survive in culture and maintained high expression of CD34. An MTT assay was carried out to determine viability after three days of culture. Lower optical density values were obtained for samples that underwent apoptosis and higher values were obtained for samples that survived in culture. Apoptosis was measured by Annexin V/propidium iodide staining. A comparison between results of MTT assay and duration of disease free survival revealed that a higher viability in vitro correlated significantly with shorter survival duration in the patient (R -0.761, p=0.002, n=13). Thus, this study further supports the hypothesis that AML patients with poor survival may be related to having blasts with a biologically more immature or stem cell-like nature.     

Immunoglobulins in saliva of preterm and full‐term infants.

The aim of this longitudinal study was to determine salivary levels of total IgA, IgG and IgM in 84 preterm and 214 full‐term infants, from birth to 18 months of age. Unstimulated whole saliva was collected from each infant at birth, and subsequently at 3‐monthly intervals. Immunoglobulin levels were estimated using an ELISA technique. At birth, IgA was detected in 147/214 (69%) full‐term infants but only 47/84 (56%) preterm infants (P < 0.01). In the case of IgG, 61% of full‐term and 56% of preterm infants showed detectable levels, whereas IgM was found in 71% and 73%, respectively. Levels of IgA and IgG rose from birth to 18 months, whereas IgM levels did not change significantly. Increases in salivary levels of IgA were associated with introduction of solid foods (P < 0.001), as well as tooth eruption (P < 0.001). Our results indicate that the majority of full‐term and preterm infants are orally immunocompetent at birth.