Sudden death of a child associated with invasive non-typeable Haemophilus influenzae infection with underlying IgG2 subclass deficiency.

Haemophilus influenzae can be divided into typeable and non-typeable strains. Although non-typeable Haemophilus influenzae (NTHi) is less likely to be a fatal bacterium, invasive NTHi infection has been reported to increase worldwide. This study presents a case of sudden death of a child with invasive NTHi infection and underlying immunoglobulin G2 (IgG2) deficiency. A two years seven months male child with a high fever was found unresponsive in bed, lying face down on a soft pillow. Later, the hospital declared the subject dead. An autopsy revealed that the only noteworthy finding was tissue congestion. The histopathological findings disclosed neutrophils within blood vessels of major organs. Meanwhile, the formation of the micro abscess was not visible, which indicated bacteremia. The bacterial blood culture was positive for Haemophilus Influenzae. Polymerase chain reaction assay revealed the absence of an entire capsule locus. The transmission electron microscopy showed that the colonies did not have polysaccharide capsules. Based on the above findings, the strain was identified as NTHi. Furthermore, the value of serum IgG2 was deficient, indicating the presence of IgG2 subclass deficiency. The subject eventually died from asphyxia by smothering due to a comorbid condition with a high fever brought on by NTHi-induced bacteremia and lying face down. IgG2 subclass deficiency contributed to the development of invasive NTHi infection. The invasive NTHi infection might present a risk of sudden death, particularly for immunocompromised children. As forensic pathologists and pediatricians may encounter such a problematic clinical condition, they should be aware of this.

Detection of deletion/insertion polymorphism profiles from single human hair shafts.

BACKGROUND: Hair is a frequently encountered biological evidence in personal identification. The amount of nuclear DNA that can be extracted from a single strand of rootless hair is most limited, making the detection of short tandem repeat (STR) polymorphisms difficult. To overcome these limitations, deletion/insertion polymorphisms (DIP) as a new type of genetic marker have shown their benefits in detecting low-copy-number DNA. The Investigator DIPplex kit contains 30 biallelic autosomal DIP and amelogenin. The analysis of DIPs combines the advantages of both STR and single nucleotide polymorphism analyses. Thus, this study aimed to detect the DIP distribution of individual hair shafts from individuals. METHODS AND RESULTS: DNA was extracted from the shaft of fresh, aged, and shed hair. After DNA was evaluated, the DIP profiles were detected by capillary electrophoresis. The results indicated that the amount of DNA extracted from hair roots was much higher than that from the hair shafts in the same individual for all samples. The degradation index values of DNA from the aged hair shafts were highest. It is classified to be "mildly degraded." Compared with their hair roots, the full DIP profiles were detected for fresh hair, 70% for aged hair, and 92% for shed hair. Contrarily, except for fresh hair shafts, only three STR loci of the aged and shed strands of hair could be genotyped using AmpFlSTR MiniFiler PCR Amplification Kit. CONCLUSIONS: These results indicate that the detection of DIP profile is an effective tool for personal identification from hair shafts, including aged hair.

Evaluation and SNP typing of DNA from ultraviolet-irradiated human bloodstains using TaqMan assay.

When detecting DNA profiles from forensic materials, it is pivotal to know the extent of degradation and which DNA marker can be genotyped. Ultraviolet (UV) is one of the common external factors that causes DNA damage, through which, an attempt to reveal cardinal genetic information can be made. In this study, after irradiation with three different UV wavelengths, UV-damaged DNA in the bloodstains was analyzed with long and short TaqMan assays using real-time PCR. In addition, both short tandem repeat (STR) profiles and single nucleotide polymorphisms (SNPs) from the damaged DNA at different stages of UV exposure were also assessed. With increasing in UV irradiation cycles, there was a delay of the amplification curves accompanied with a decrease in the DNA amounts collected. Despite the amplification of STR genotype was not altered after 75 cycles of UVC irradiation, all 12 SNP loci could still be detected. Furthermore, a short-assay line was detected in the absence of an amplification of the evaluation curve. The results indicate that, although the DNA template might not be useful and suitable for analysis of STR profile, this approach is of some values in detecting SNPs.

Real-time PCR assay for the detection of picoplankton DNA distribution in the tissues of drowned rabbits.

The detection of plankton DNA is one of the important methods for the diagnosis of drowning from postmortem tissues. This study investigated the quantities of picoplankton (Cyanobacteria) DNA in the lung, liver, kidney tissues and blood of drowned and non-drowned rabbits, and the sensitivity of detection of picoplankton DNA by polymerase chain reaction (PCR) detect for the diagnosis of death from drowning. For this purpose, the DNA of the 16S ribosomal RNA gene of picoplankton was quantitatively assayed from the tissues of drowned and non-drowned rabbits immersed in water after death. Each of the liver, kidney and lung tissues and blood were obtained from drowned and non-drowned rabbits. Picoplankton DNA in the tissues was extracted using the DNeasy® Blood & Tissue kit to determine the yield of picoplankton DNA from each tissue. TaqMan real-time PCR was performed for quantitative analysis of picoplankton DNA. Target DNA was detected in the liver, kidney and lung samples obtained from the drowned rabbits, while no picoplankton DNA was detected in the non-drowned rabbit tissues (except in lung samples). The results verified that direct PCR for the detection of picoplankton DNA is useful for the diagnosis of drowning. Although we observed seasonal changes in the quantity of picoplankton in river water, we were able to detect DNA from various organs of drowned bodies during the season when picoplankton were not the most abundant.

Fundamental characteristics of synthetic adsorbents intended for industrial chromatographic separations.

With the aim of obtaining comprehensive information on the selection of synthetic adsorbents for industrial applications, effect of pore and chemical structure of industrial-grade synthetic adsorbents on adsorption capacity of several pharmaceutical compounds was investigated. For relatively low molecular mass compounds, such as cephalexin, berberine chloride and tetracycline hydrochloride, surface area per unit volume of polystyrenic adsorbents dominated the equilibrium adsorption capacity. On the contrary, effect of pore size of the polystyrenic adsorbents on the equilibrium adsorption capacity was observed for relatively high molecular mass compounds, such as rifampicin, Vitamin B12 and insulin. Polystyrenic adsorbent with high surface area and small pore size showed small adsorption capacity for relatively high molecular mass compounds, whereas polystyrenic adsorbent with relatively small surface area but with large pore size showed large adsorption capacity. Effect of chemical structure on the equilibrium adsorption capacity of several pharmaceutical compounds was also studied among polystyrenic, modified polystyrenic and polymethacrylic adsorbents. The modified polystyrenic adsorbent showed larger adsorption capacity for all compounds tested in this study due to enhanced hydrophobicity. The polymethacrylic adsorbent possessed high adsorption capacity for rifampicin and insulin, but it showed lower adsorption capacity for the other compounds studied. This result may be attributed to hydrogen bonding playing major role for the adsorption of compounds on polymethacrylic adsorbent. Furthermore, column adsorption experiments were operated to estimate the effect of pore characteristics of the polystyrenic adsorbents on dynamic adsorption behavior, and it is found that both surface area and pore size of the polystyrenic adsorbents significantly affect the dynamic adsorption capacity as well as flow rate.

Use of synthetic adsorbents in preparative normal-phase liquid chromatography.

Normal-phase liquid chromatographic separation using polymeric synthetic adsorbents was investigated. The retention behavior of dialkyl phthalates under a hexane-isopropanol eluent system revealed that both polystyrenic and polymethacrylic adsorbents can be used for normal-phase liquid chromatography, and that the polymethacrylic adsorbent has stronger retentivity than the polystyrenic adsorbent. Applicability of these synthetic adsorbents, especially the polymethacrylic adsorbents, was verified by the separation of polyunsaturated fatty acids, schizandrin in Schisandra chinensis fruit, tocopherols and tocotrienols in vegetable oils using a 10-microm adsorbent packed into an HPLC column. Furthermore, the separation was expanded to preparative scale by using polymethacrylic adsorbents with 17- and 31-microm fine grade particle sizes. The effect of loading volume on the retention or separation was also examined, and separation was maintained up to the loading of several grams per liter adsorbent. These results demonstrate that commercially available synthetic adsorbents possess considerable performance as normal-phase chromatographic media for more precise purification of bioactive compounds. including pharmaceuticals and nutraceuticals with scale-up possibilities.