Variants of the melanocortin 1 receptor gene (<Emphasis Type="Italic">MC1R</Emphasis>) and <Emphasis Type="Italic">P</Emphasis> gene as indicators of the population origin of an individual

The population origin of an individual is often requested to be determined from specimens left at a crime scene for identifying a suspect and individual identity. The melanocortin 1 receptor gene (MC1R) and P gene are associated with human pigmentation. Although several studies have reported that these genes are highly polymorphic in human populations, it is unclear if the allele variants can be used to determine the population origin of an individual. We aimed to determine the ethnic origin of an individual by using single nucleotide polymorphisms (SNPs). Eighteen SNPs in the MC1R gene and P genes were genotyped in 52 individuals by the direct sequencing method, and 4 SNPs (MC1R gene: R163Q and P gene: IVS5 + 1001, IVS13 + 113, and H615R) were selected on the basis of differences in frequencies. Subsequently, we genotyped these four SNPs in 422 volunteers from six ethnically defined populations using a polymerase chain reaction-based assay. The results revealed that the allele variants were present with high frequencies in Asian populations but were low in European and African populations. On the basis of these results, we defined a specific combination of a genotype (R163Q) and a diplotype group (IVS5 + 1001, IVS13 + 113, and H615R). This study indicates that the specific combination of a genotype and a diplotype group would be effective in estimating the population origin of an individual from a list of population groups. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

A parent-of-origin detectable polymorphism in the hypermethylated region upstream of the human<Emphasis Type="Italic"> H19</Emphasis> gene

The H19 gene is a paternally imprinted gene located on chromosome 11p15.5. In this study the H19FR haplotype polymorphism including three SNPs upstream of the H19 gene was investigated. Six genotypes derived from three alleles were detected in the Japanese population by means of PCR and subsequent constant denaturing gel electrophoresis. Based on the methylation status of the genomic DNA from blood samples, selective detection of the parental allele for H19FR was examined by using two types of enzyme, the methylation-sensitive restriction enzymes HpaII or HhaI and McrBC. Genomic DNA digested by either HpaII or HhaI, revealed a single band derived from the paternal allele, as a result of cleavage of unmethylated recognition sites on the maternal allele. On the contrary, the use of McrBC, which can digest a methylated paternal sequence, resulted in exclusively amplifying the maternal allele. This method could be one of the useful techniques for discriminating the parental origin of alleles.     

<Emphasis Type="Italic">Candida albicans</Emphasis> osteomyelitis of the cervical spine

Fungal osteomyelitis is a rare infection that usually develops in immunocompromised patients. Additionally, involvement of the cervical spine by Candida albicans is extremely rare; only three previous cases of Candida vertebral osteomyelitis have been reported in the literature. The diagnosis may be delayed due to nonspecific radiologic findings and a slow progression. We report the CT, MRI, bone scan, and PET-CT findings in a patient who developed Candida osteomyelitis, which was initially misdiagnosed as metastasis, at the atlas and axis following treatment for nasopharyngeal cancer.     

Fulminant endogenous <Emphasis Type="Italic">Klebsiella pneumoniae</Emphasis> endophthalmitis: imaging findings

Endogenous endophthalmitis is a rare but serious complication of Klebsiella pneumoniae infection that has been predominantly reported to occur in diabetic patients of East Asian origin with K. pneumoniae liver abscesses. The clinical symptoms and signs of endogenous endophthalmitis are nonspecific and may mimic other causes of an acute non-traumatic eye. Permanent visual loss and blindness are common sequelae because of delayed diagnosis and treatment. Computed tomography and magnetic resonance imaging can help to differentiate endophthalmitis from other causes of acute non-traumatic eye when the clinical findings are equivocal. Fluid attenuated inversion recovery and diffusion-weighted imaging with apparent diffusion coefficient map are superior to T2-weighted and gadolinium-enhanced T1-weighted sequences in demonstrating intra-ocular abscesses.     

Biodistribution and radiation dosimetry of the norepinephrine transporter radioligand (<Emphasis Type="Italic">S</Emphasis>,<Emphasis Type="Italic">S</Emphasis>)-[<Superscript>18</Superscript>F]FMeNER-D<Subscript>2</Subscript>: a human whole-body PET study

Purpose (S,S)-[¹⁸F]FMeNER-D₂ is a recently developed positron-emission tomography (PET) radioligand for in vivo quantification of the norepinephrine transporter system. The aim of this study was to provide dosimetry estimates for (S,S)-[¹⁸F]FMeNER-D₂ based on human whole-body PET measurements. Methods PET scans were performed for a total of 6.4 h after the injection of 168.9 ± 31.5 MBq of (S,S)-[¹⁸F]FMeNER-D₂ in four healthy male subjects. Volumes of interest were drawn on the coronal images. Estimates of the absorbed dose of radiation were calculated using the OLINDA software. Results Uptake was largest in lungs, followed by liver, bladder, brain and other organs. Peak values of the percent injected dose (%ID) at a time after radioligand injection were calculated for the lung (21.6%ID at 0.3 h), liver (5.1%ID at 0.3 h), bladder (12.2%ID at 6 h) and brain (2.3%ID at 0.3 h). The largest absorbed dose was found in the urinary bladder wall (0.039 mGy/MBq). The calculated effective dose was 0.017 mSv/MBq. Conclusion Based on the distribution and dose estimates, the estimated radiation burden of (S,S)-[¹⁸F]FMeNER-D₂ is lower than that of [¹⁸F]FDG. The radioligand would allow multiple PET examinations in the same research subject per year.     

Feasibility of sodium/iodide symporter gene as a new imaging reporter gene: comparison with<Emphasis Type="Italic"> HSV1-tk</Emphasis>

Positron emission tomography (PET) imaging reporter genes, such as HSV1-tk and D₂ receptor genes, make it possible to visualise gene expression non-invasively and repetitively in vivo. However, these systems require the synthesis of complicated substrates and the availability of expensive PET equipment. Expression of the sodium/iodide symporter (NIS) gene can be easily monitored with radioiodines and technetium-99m using a gamma camera. To evaluate the possibility of using NIS as an imaging reporter gene, we compared its characteristics with those of the conventional HSV1-tk gene. The CM cell line was made by transfecting the HSV1-tk gene into CT-26 (mouse colon carcinoma cell line). The CTN and CMN cell lines were then made by transfecting the NIS gene into CT-26 and CM. We measured the uptake of iodine-125 iodovinyldeoxyuridine ([¹²⁵I]IVDU) and ¹²⁵I to evaluate the expression of the HSV1-tk and NIS genes, respectively. Each cell line was injected into four flank sites in Balb/c mice. The biodistribution study was performed after intravenously injecting [¹²⁵I]IVDU and ¹³¹I, and ¹³¹I scintigraphy was performed for the evaluation of NIS expression. In vitro studies indicated that CTN and CMN had 40- to 79-fold and 150- to 256-fold higher uptake of ¹²⁵I than CT-26 and CM, respectively. Furthermore, CM and CMN showed 57- to 69-fold higher uptake of [¹²⁵I]IVDU than CT-26 and CTN. NIS gene expression and ¹²⁵I accumulation were found to be directly correlated (R ²=0.923), as were HSV1-tk gene expression and [¹²⁵I]IVDU accumulation (R ²=0.956). Calculated signal per unit NIS and HSV1-tk mRNA expression was 23,240±3,755 cpm and 34,039±5,346 cpm, respectively. In vivo study indicated that CTN and CMN had 2.3- and 5.8-fold higher uptake of ¹³¹I than CT-26 and CM, and 1.8- and 3.5-fold higher uptake of [¹²⁵I]IVDU than CT-26 and CTN. Scintigraphy using ¹³¹I easily visualised CTN and CMN tumours. In conclusion, the NIS gene may be viewed as an imaging reporter gene with comparable performance to the HSV1-tk gene for monitoring target gene expression.     

Encephalitis following <Emphasis Type="Italic">Mycoplasma</Emphasis> pneumonia (2007: 6b)

We report an unusual case concerning encephalitis following Mycoplasma pneumonia. This interpretation corner case showed an unusual pattern of lesion distribution, resembling primary nervous system angiitis. The distribution of the lesions according to the perivascular spaces suggests a predominant leptomeningeal infiltration.     

Mycotic osteomyelitis due to<Emphasis Type="Italic"> Scedosporium Apiospermum:</Emphasis> MR imaging-pathologic correlation

Mycotic osteomyelitis is rare and occurs in immunocompromised patients after inoculation of the pathogen at a penetrating trauma site. Mycotic osteomyelitis due to Scedosporium Apiospermum is extremely rare, with only 13 cases of septic arthritis reported previously. Ours is only the third case of S. apiospermum osteomyelitis in an immunocompromised patient and the only patient with a histopathologic diagnosis from an amputation specimen. Recognition of this pathogen may be delayed due to insidious onset and negative joint fluid cultures, often requiring synovial or bone biopsies to establish the diagnosis. Delay in appropriate treatment may result in disseminating infection or even death.     

Quantification of (<Emphasis Type="Italic">R</Emphasis>)-[<Superscript>11</Superscript>C]PK11195 binding in rheumatoid arthritis

Purpose  Rheumatoid arthritis (RA) involves migration of macrophages into inflamed areas. (R)-[¹¹C]PK11195 binds to peripheral benzodiazepine receptors, expressed on macrophages, and may be used to quantify inflammation using positron emission tomography (PET). This study evaluated methods for the quantification of (R)-[¹¹C]PK11195 binding in the knee joints of RA patients. Methods  Data from six patients with RA were analysed. Dynamic PET scans were acquired in 3-D mode following (R)-[¹¹C]PK11195 injection. During scanning arterial radioactivity concentrations were measured to determine the plasma (R)-[¹¹C]PK11195 concentrations. Data were analysed using irreversible and reversible one-tissue and two-tissue compartment models and input functions with various types of metabolite correction. Model preferences according to the Akaike information criterion (AIC) and correlations between measures were evaluated. Correlations between distribution volume (V_d) and standardized uptake values (SUV) were evaluated. Results  AIC indicated optimal performance for a one-tissue reversible compartment model including blood volume. High correlations were observed between V_d obtained using different input functions (R ²=0.80–1.00) and between V_d obtained with one- and two-tissue reversible compartment models (R ²=0.75–0.94). A high correlation was observed between optimal V_d and SUV after injection (R ²=0.73). Conclusion  (R)-[¹¹C]PK11195 kinetics in the knee were best described by a reversible single-tissue compartment model including blood volume. Applying metabolite corrections did not increase sensitivity. Due to the high correlation with V_d, SUV is a practical alternative for clinical use. Financial support: There were no sources of financial support other than the VU University Medical Centre. The authors had full control of all primary data and agree to allow EJNM to review their data if requested.     

CT imaging of acute <Emphasis Type="Italic">E. Coli</Emphasis>-related colitis

Patients with abdominal pain and bloody diarrhea often present in the acute setting to the emergency department for evaluation. After the appropriate clinical assessment, cross-sectional imaging is often utilized to evaluate for the severity of the disease. Although a wide spectrum of findings may be seen, diffuse colonic mural thickening, consistent with pancolitis, is most common. We report an Escherichia coli 0157:H7-related pancolitis in a patient with spinach intake linked to the recent outbreak.     

Real-time quantitative PCR assay for the detection of <Emphasis Type="Italic">Helicobacter pylori</Emphasis>: no association with sudden infant death syndrome

Helicobacter pylori infection is known to be one of the most common chronic infectious diseases in humans. Recently, a hypothesis was proposed that H. pylori infection could be a frequent cause for sudden infant death syndrome (SIDS). We have investigated this postulated association by examining formalin-fixed paraffin-embedded gastric tissues of a retrospective cohort of 94 SIDS cases: The presence of H. pylori was inferred from a newly developed real-time quantitative PCR assay with SYBR Green I detection. This assay is based on the amplification of the single-copy H. pylori–specific glmM gene. Accuracy and precision were verified using a plasmid containing a 977-bp fragment of this glmM gene. The assay was very sensitive, and as few as 30 template copies per PCR reaction could be detected even in the presence of excess human DNA. The assay was validated on mucosal biopsy samples of patients with known H. pylori infections. Interfering effects due to SIDS gastric tissue were excluded. Only two (2.1%) of the SIDS samples yielded H. pylori DNA copy numbers and only beyond the lowest standard concentration. These results could be confirmed independently by immunohistochemistry using an H. pylori–specific antibody. Thus, an infection by H. pylori is very rare in cases of SIDS, and thus the postulated association of H. pylori infection and SIDS cannot be confirmed.This work was supported by grants from IMF (Innovative Medizinische Forschung, BA 2 1 01 05), Münster University Hospital, Germany, and the Ministry of Education and Science of Germany (01 ED 9401).     

Value of <Emphasis Type="Italic">O</Emphasis>-(2-[<Superscript>18</Superscript>F]fluoroethyl)-<Emphasis Type="SmallCaps">l</Emphasis>-tyrosine PET for the diagnosis of recurrent glioma

Purpose The prognosis of patients with recurrent gliomas depends on reliable and early diagnosis of tumour recurrence after initial therapy. In this context, magnetic resonance imaging (MRI) and computed tomography (CT) often fail to differentiate between radiation- and tumour-induced contrast enhancement. Furthermore, absence of contrast enhancement, or even of ¹⁸F-fluorodeoxyglucose uptake in PET, does not exclude recurrence. The aim of this study was to establish the diagnostic value of O-(2-[¹⁸F]fluoroethyl)-l-tyrosine (FET) PET in recurrent gliomas.Methods Fifty-three patients with glioma (primary grading: 27=WHO grade IV, 16=grade III, 9=grade II, 1=grade I) and clinically suspected recurrence underwent FET PET scans 4–180 months after different treatment modalities. For semiquantitative evaluation, maximal SUV (SUV_max) and mean SUV within 80% and 70% isocontour thresholds (SUV₈₀/SUV₇₀) were evaluated and the respective ratios to the background (BG) were calculated. PET results were correlated with MRI/CT, clinical follow-up or biopsy findings.Results All patients presented with FET uptake, of varying intensity, in the area of the primary tumour after initial therapy. In the 42 patients with confirmed recurrence, there was additional distinct focal FET uptake with significantly higher values compared with those in the 11 patients without clinical signs of recurrence and showing only low and homogeneous FET uptake at the margins of the resection cavity. With respect to tumour grading, there was a slight but non-significant increase from WHO II (SUV_max/BG: 2.53±0.28) to WHO III (SUV_max/BG: 2.84±0.49) and WHO IV (SUV_max/BG: 3.55±1.07) recurrence.Conclusion FET PET reliably distinguishes between post-therapeutic benign lesions and tumour recurrence after initial treatment of low- and high-grade gliomas.     

Validation of the multiplex kit<Emphasis Type="Italic"> genRES</Emphasis>MPX-2 for forensic casework analysis

Validation studies were carried out using the commercially available PCR multiplex system genRESMPX-2. In addition to amelogenin, this system comprises the complete set of eight STR systems which are components of the German DNA database established in 1998 by the Federal Criminal Office of Germany (BKA). The minimum amount of template DNA which gave a complete DNA pattern ranged between 100 pg and 200 pg. Mixed samples could clearly be assigned from ratios between 1:5 (ACTBP2) and 1:20 (VWA, FGA). Experimental investigations with different forensic materials, environmental studies, reproducibility and precision data as well as practical casework analysis revealed that the genRESMPX-2 kit can be regarded as a sensitive, reliable and robust multiplex system even in the case of samples containing limited amounts or degraded DNA.A. Junge and T. Lederer contributed equally to the data presented     

<Emphasis Type="Italic">Mycobacterium marinum</Emphasis>: MR imaging and clinical course of a rare soft tissue infection

Mycobacterium marinum is a rare cause of soft tissue infections. The imposing MR appearance of the soft tissue involvement is in contrast to the chronic painless clinical manifestation.     

Breast tumor characteristics of <Emphasis Type="Italic">BRCA1</Emphasis> and <Emphasis Type="Italic">BRCA2</Emphasis> gene mutation carriers on MRI

The appearance of malignant lesions in BRCA1 and BRCA2 mutation carriers (BRCA-MCs) on mammography and magnetic resonance imaging (MRI) was evaluated. Thus, 29 BRCA-MCs with breast cancer were retrospectively evaluated and the results compared with an age, tumor size and tumor type matched control group of 29 sporadic breast cancer cases. Detection rates on both modalities were evaluated. Tumors were analyzed on morphology, density (mammography), enhancement pattern and kinetics (MRI). Overall detection was significantly better with MRI than with mammography (55/58 vs 44/57, P = 0.021). On mammography, lesions in the BRCA-MC group were significantly more described as rounded (12//19 vs 3/13, P = 0.036) and with sharp margins (9/19 vs 1/13, P = 0.024). On MRI lesions in the BRCA-MC group were significantly more described as rounded (16/27 vs 7/28, P = 0.010), with sharp margins (20/27 vs 7/28, P < 0.001) and with rim enhancement (7/27 vs 1/28, P = 0.025). No significant difference was found for enhancement kinetics (P = 0.667). Malignant lesions in BRCA-MC frequently have morphological characteristics commonly seen in benign lesions, like a rounded shape or sharp margins. This applies for both mammography and MRI. However the possibility of MRI to evaluate the enhancement pattern and kinetics enables the detection of characteristics suggestive for a malignancy.     

Comparison of [<Superscript>18</Superscript>F]FHBG and [<Superscript>14</Superscript>C]FIAU for imaging of <Emphasis Type="Italic">HSV1-tk</Emphasis> reporter gene expression: adenoviral infection vs stable transfection

Earlier studies involving comparison of different reporter probes have shown conflicting results between pyrimidine nucleosides [e.g., 2'-fluoro-2'-deoxy-1--d-arabinofuranosyl-5-iodouracil (FIAU)] and acycloguanosine derivatives [e.g., penciclovir (PCV), 9-(4-fluoro-3-hydroxymethylbutyl)guanine (FHBG)]. We hypothesized that this reported discrepancy may be related to how the reporter gene is delivered to the cells—stably transfected vs adenoviral infection. We directly compared the uptake characteristics of [¹⁸F]FHBG, [³H]PCV, and [¹⁴C]FIAU in cell culture and in vivo using an adenoviral mediated gene transfer model and stably transfected cells. We further compared the uptake of three reporter probes using both HSV1-tk and a mutant HSV1-sr39tk expressing cells to assess the optimal reporter probe/reporter gene combination. [¹⁴C]FIAU accumulation was greater than that of [³H]PCV and [¹⁸F]FHBG in control cells and in HSV1-tk stably transfected cells (P<0.001). After infection of C6 cells with AdCMV-HSV1-tk (1.5×10⁸ pfu), [¹⁸F]FHBG and [³H]PCV accumulation was significantly greater than that of [¹⁴C]FIAU (P<0.01). [¹⁸F]FHBG and [³H]PCV accumulated to a significantly greater extent than [¹⁴C]FIAU in C6-stb-sr39tk+ and AdCMV-HSV1-sr39tk infected C6 cells (P<0.001). Results from the nude mice supported the results in cell culture. [¹⁴C]FIAU led to significantly higher %ID/g in C6-stb-tk+ xenografts than [¹⁸F]FHBG (P<0.05); however, compared with [¹⁴C]FIAU, [¹⁸F]FHBG led to as high %ID/g in HSV1-tk expressing hepatocytes and to significantly greater %ID/g in C6-stb-sr39tk+ xenografts and HSV1-sr39tk expressing hepatocytes. Dynamic sequential images showed that [¹⁸F]FHBG was well retained in HSV1-sr39tk expressing cells (C6-stb-sr39tk+) for at least 4 h after injection, while it was rapidly cleared from HSV1-tk expressing cells (MH3924A-stb-tk+). [¹⁴C]FIAU accumulated in HSV1-tk stably expressing cells to a greater extent than either [³H]PCV or [¹⁸F]FHBG. However, the accumulation of [³H]PCV and [¹⁸F]FHBG in adenoviral infected C6 cells or hepatocytes was equivalent to or greater than that of [¹⁴C]FIAU. These results may be due to intracellular biochemical changes (e.g., thymidine) when cells are infected with adenovirus. For adenoviral studies, the [¹⁸F]FHBG/HSV1-sr39tk combination was shown to be more sensitive than the [¹⁴C]FIAU/HSV1-tk combination HSV1-tk.     

Organizing pneumonia associated with <Emphasis Type="Italic">Mycoplasma pneumoniae</Emphasis> infection

Mycoplasma pneumoniae infection is known to produce infiltrative and/or nodular opacities that are often localized. A patient presented to us with diffuse centrilobular, peribronchovascular, and perilobular opacities after documented Mycoplasma pneumoniae infection. A surgical biopsy proved the lung disease to be organizing pneumonia, which dramatically resolved in response to treatment with corticosteroid. This case represents an unusual radiological manifestation associated with M. pneumoniae infection, thereby stressing the importance of this disease in the differential diagnosis for patients with diffuse opacities of the lungs.     

Fatal influenza A infection with<Emphasis Type="Italic"> Staphylococcus aureus</Emphasis> superinfection in a 49-year-old woman presenting as sudden death

A fatal case of influenza A infection with Staphylococcus aureus superinfection in a previously healthy 49-year-old woman presenting as sudden, unexpected death is reported. Autopsy revealed severe necrotizing tracheobronchitis and hemorrhagic pneumonia. Microscopic examination of the trachea and bronchi showed mucosal necrosis and a dense lympho-monocytic infiltration of all layers. The lungs showed focal hemorrhagic pneumonia. No pathological changes were detectable in the myocardium. Influenza A virus was detected in bronchi and lung samples obtained during autopsy by the polymerase chain reaction (PCR) and bacterial superinfection with Staphylococcus aureus was shown by culturing from tracheal, bronchial and pulmonary swabs obtained during autopsy. PCR assays for the detection of Panton-Valentine leukocidin performed from all samples were negative. This case demonstrates the need for an interdisciplinary approach towards an organism-specific diagnosis of potentially infection-related deaths undergoing a medico-legal autopsy. With improved diagnostic possibilities such as PCR and DNA sequencing, forensic pathologists can, in close association with the field of microbiology, make a significant contribution to the detection of highly infectious agents which must be notified to the authorities. This will increase particularly the knowledge about the influence of these agents on sudden, unexpected deaths in outpatients.     

Imaging the norepinephrine transporter with positron emission tomography: initial human studies with (<Emphasis Type="Italic">S,S</Emphasis>)-[<Superscript>18</Superscript>F]FMeNER-D<Subscript>2</Subscript>

Introduction (S,S)-[¹⁸F]FMeNER-D₂ is a recently developed positron emission tomography (PET) ligand for in vivo quantification of norepinephrine transporter. A monkey occupancy study with the radioligand indicated that (S,S)-[¹⁸F]FMeNER-D₂ can be useful for quantitative PET analysis. In this preliminary study, regional distributions in the living human brain were evaluated. Materials and methods Brain PET measurements were performed for a total of 255 min after the injection of 188.3 ± 5.7 MBq of (S,S)-[¹⁸F]FMeNER-D₂ in four healthy male subjects. Regions of interests were drawn on the thalamus and the caudate in the coregistered MRI/PET images. Results (S,S)-[¹⁸F]FMeNER-D₂ displayed good brain penetration and selective retention in regions rich in norepinephrine reuptake sites. The transient peak equilibrium was reached during the PET measurements. The ratios of radioactivity uptake in the thalamus to that in the caudate were 1.50 ± 0.06 for the time period of 90–255 min. Conclusion The present preliminary investigation indicates that (S,S)-[¹⁸F]FMeNER-D₂ has suitable characteristics for probing the norepinephrine reuptake system with PET in the human brain.