Detection of Chlamydia trachomatis and Neisseria gonorrhoeae in urogenital and oral specimens using the cobas® 4800, APTIMA Combo 2® TMA, and ProbeTec™ ET SDA assays

This prospective, multicenter clinical trial was conducted to compare the performance of the cobas(®) 4800 CT/NG, APTIMA Combo 2(®), and ProbeTec(™) ET CT/GC assays for the detection of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) in Japan. From 1274 male and female patients, more than 1900 urine, endocervical and throat specimens were collected. Positive and negative concordance rates for CT and NG results obtained for urine and endocervical samples collected from the same patient were high in all three assays (range 96.0-99.6%). The accuracy of the cobas(®) 4800 CT/NG test did not differ significantly from that of the APTIMA Combo 2(®) and ProbeTec(™) ET CT/GC assays. The accuracy of the assays did not change depending on the order of collection of endocervical specimens. Concordance rates for results obtained for throat swabs and mouthwashes in the ProbeTec(™) ET CT/GC and cobas(®) 4800 CT/NG assays, respectively, were 98.8% for CT and 95.1% for NG. These data suggest that the cobas(®) 4800 CT/NG test is a reliable and highly accurate diagnostic tool for the detection of CT and NG in urine, genital, and oral specimens. Owing to the high correlation of urine and endocervical swab results and the ease of acquisition, urine samples are suggested as the specimen of choice for screening of CT and NG.

Involvement of brown adipose tissue in subcutaneous fat necrosis of the newborn

BACKGROUND

Subcutaneous fat necrosis (SCFN) of the newborn is a rare condition that manifests within days after birth. The interscapular region, axillae and shoulders are the most commonly affected sites, corresponding to anatomic sites of brown adipose tissue (BAT) in newborns.

OBJECTIVE

We postulated a specific involvement of BAT in SCFN and searched for brown adipocytes at affected sites.

METHODS

Biopsy specimens were immunostained with antibodies against uncoupling protein 1 (UCP-1) and examined by electron microscopy. We also examined BAT by (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography and computed tomography (PET-CT) scanning.

RESULTS

A few cells in biopsy specimens from two patients bound antibodies against UCP-1, and brown adipocytes were detected at several stages of degeneration. PET-CT scans revealed lower uptake of (18)F-FDG at major sites of SCFN.

CONCLUSION

SCFN and BAT can be found at the same sites, suggesting a pathophysiological connection.

Pure laparoscopic hepatectomy for hepatocellular carcinoma patients with severe liver cirrhosis

Hepatocellular carcinoma often arises in cirrhotic livers. Patients with severe liver cirrhosis who undergo hepatectomy often develop postoperative liver failure, even if the hepatectomy is limited. Here, we report six patients with severe liver cirrhosis (Child-Pugh B/C and indocyanine green retention rate at 15 min ≥ 40%) who underwent pure laparoscopic hepatectomy. Their perioperative course was favorable and comparable to that of other hepatocellular carcinoma patients with mild-moderate liver cirrhosis. In patients with severe liver cirrhosis, pure laparoscopic hepatectomy minimizes the disturbance in collateral blood and lymphatic flow caused by laparotomy and liver mobilization, as well as the mesenchymal injury caused by compression of the liver. It limits complications such as massive ascites, which can lead to severe postoperative liver failure. Good candidates for the procedure include patients with severe liver cirrhosis who have tumors on the liver surface and in whom adaptation to ablation therapy is difficult and/or who experience local recurrence after repeat treatments.

Levels of specific immunoglobulin G to the forsythia detaching factor of Tannerella forsythia in gingival crevicular fluid are related to the periodontal status

BACKGROUND AND OBJECTIVE

Forsythia detaching factor (FDF) is a putative virulence factor of Tannerella forsythia that induces detachment of adherent cells and interleukin-8 production in human fibroblasts. The objective of the present study was to clarify the relationship between anti-FDF IgG levels in gingival crevicular fluid and the clinical status in patients with periodontitis and in healthy subjects.

MATERIAL AND METHODS

Gingival crevicular fluid and subgingival plaque samples were obtained from both the diseased and healthy sites of 37 patients with periodontitis and from 30 healthy subjects. Anti-FDF IgG levels were evaluated, and both the fdf gene and T. forsythia 16S ribosomal RNA (rRNA) were detected using the PCR.

RESULTS

Anti-FDF IgG levels (of both diseased and healthy sites) of patients with periodontitis were significantly higher than those of healthy subjects. Among the patients with periodontitis, anti-FDF IgG levels of healthy sites were significantly higher than those of diseased sites and the levels showed negative correlations with probing pocket depth and clinical attachment level. Among the patients with periodontitis, T. forsythia 16S rRNA was detected in 18 of 37 diseased sites and in 5 of 29 healthy sites, and the fdf gene was detected in 19 of 37 diseased sites and in 7 of 29 healthy sites. By contrast, no healthy subjects were positive for T. forsythia 16S rRNA or the fdf gene.

CONCLUSION

These data suggest that anti-FDF IgG levels in gingival crevicular fluid are related to the periodontal status.

Penumbral mismatch is underestimated using standard volumetric methods and this is exacerbated with time

BACKGROUND AND AIMS

The mismatch between perfusion weighted images (PWI) and diffusion weighted images (DWI) using MR is increasingly being applied in patient selection for therapeutic trials. Two approaches to the calculation of the mismatch volume exist--the commonly used volumetric and the more precise co-registration method, the latter of which considers lesion topography. That there are differences in the mismatch volume analysed by each method and that these are time dependent was hypothesised.

METHODS

Patients within 48 h of ischaemic stroke onset had baseline MR PWI/DWI mismatch and T2 outcome volumes at 3 months. Volumetric mismatch volume was defined as PWI minus DWI lesion. Co-registration mismatch volume was defined as the PWI defect lesion not overlapped by the co-registered DWI lesion.

RESULTS

72 patients of median age 74.0 years were studied. Median baseline MR was at 5.9 h (IQR 3.0, 20.4 h) after stroke onset. Consistent underestimation of the mismatch volume occurred using the volumetric method (volumetric median 9.3 ml, IQR 0, 63 ml; co-registration median 20.1 ml, IQR 3.2, 69.8 ml; p<0.0001). This difference increased with time from stroke onset (p = 0.006).

CONCLUSIONS

Volumetric analysis consistently underestimates the PWI/DWI mismatch volume compared with the more precise co-registration method. This effect increases with time.

Pro-inflammatory cytokine production from normal human fibroblasts is induced by Tannerella forsythia detaching factor

BACKGROUND AND OBJECTIVE

Tannerella forsythia is a periodontal pathogen. Recently, we have reported that the cytopathic component of T. forsythia contains two distinct factors. One arrests the cell cycle at the G2 phase and the other, named forsythia detaching factor, detaches adhesion-dependent immortalized human cells. In this study, we investigated the biological function of forsythia detaching factor using human normal fibroblasts.

MATERIAL AND METHODS

A recombinant forsythia detaching factor, reported previously, was used. TIG-3 cells, cultured in the absence or presence of forsythia detaching factor, were lysed and the supernatant was analyzed by western blotting with polyclonal forsythia detaching factor antibodies. The cells were subsequently fractionated to isolate the cytoplasmic, mitochondrial and remaining fractions. In order to measure the activity of mitochondria using nicotinamide adenine dinucleotide-linked reductase, the water-soluble tetrazolium method was used. The mitochondrial oxidative membrane potential was estimated by measuring the oxidization-dependent fluorogenic conversion of dihydrotetramethylrosamine using flow cytometry. The concentration of interleukin-8 in the culture supernatant was assayed using a Human IL-8 ELISA kit.

RESULTS

Forsythia detaching factor-treated cells detached from the substratum and aggregated from 3 to 24 h. Then, the detached cells resumed adhesion and proliferated after 48 h. The western blot analysis revealed that most forsythia detaching factor trans-located into the mitochondrial fraction. Forsythia detaching factor suppressed the nicotinamide adenine dinucleotide-linked reductase activity in a dose-dependent manner and consequently increased the mitochondrial oxidative membrane potential. The production of interleukin-8 was reinforced in forsythia detaching factor-treated cells at 72 h through an increase of the mitochondrial oxidative membrane potential.

CONCLUSION

The forsythia detaching factor might be involved in the virulence of T. forsythia through induction of the pro-inflammatory cytokine interleukin-8.

Isolation and identification of a cytopathic activity in Tannerella forsythia

Interactions between pathogens and host induce human disorders including periodontitis, disintegration of the tooth supporting tissues. Tannerella forsythia has been linked to the periodontitis and several cytopathic reagents have been found in the bacterium; however, its contribution to the disease remains unclear. Biochemical approach to explore the cytopathic effect revealed two distinct activities in T. forsythia (ATCC 43037) extract; one detaches adherent cells from substratum and another arrests cells at G2. An executor of former activity, forsythia detaching factor (FDF) was identified; its genomic sequence and peptidase activity revealed that FDF is a substantial form of putative PrtH; prtH gene was hypothetically identified directly from a DNA fragment of the bacterium and its native product has never been shown. Since FDF was found in the bacterial culture supernatant, its activity implies a contribution to the disintegration of tissues although the mechanism how FDF disturbs cellular anchors remains elusive.

Rapid detection and differentiation of Gram-negative and Gram-positive pathogenic bacteria in urine using TaqMan probe

Urinary tract infection has been shown to be quite complicated and often difficult to diagnose and treat. For appropriate diagnosis, it is very important to find the correct Gram stain classification as soon as possible, especially in severe cases where there is a possibility of severe sepsis developing. In order to solve this problem, we developed a new method to detect a Gram stain of bacteria obtained from 1 ml of urine from urinary tract infection patients using a consensus real-time PCR protocol with a TaqMan probe that allows detection of spiked bacterial 16S DNA from urine. We extracted DNA of 55 urine samples obtained from patients with complicated urinary tract infection and at the same time performed urine culture testing. After DNA extraction, they were subjected to real-time PCR using a TaqMan discrimination system. Sixteen kinds of bacteria were cultured from the urine culture testing. Of these bacteria, eight were classified as Gram-positive bacteria and the other eight were classified as Gram-negative bacteria. Of the 55 samples, the TaqMan technique result showed 27 samples that were classified as Gram-negative bacteria; 11 samples that were Gram-positive, 10 that included both Gram-negative and -positive bacteria, and 7 that showed no amplification. The classifications of all samples corresponded exactly to those determined by urine culture testing. The present genotyping method of real-time PCR using a TaqMan discrimination system could be applied to the rapid detection of Gram-positive or -negative bacteria in urine of urinary tract infection patients. This assay can differentiate those species tested, but whether the presence of other (untested) bacteria could lead to misinterpretation is unknown. For further investigation, it is important to test other (untested) bacteria in the near future.

Susceptibilities of Neisseria gonorrhoeae to fluoroquinolones and other antimicrobial agents in Hyogo and Osaka, Japan

OBJECTIVES

Decreasing susceptibility of Neisseria gonorrhoeae to fluoroquinolones has been reported in several countries. Knowledge of local N gonorrhoeae susceptibilities to various antimicrobials is important for establishing a rational treatment strategy in each region.

METHODS

Isolates of N gonorrhoeae from male urethritis patients attending four urological clinics in Hyogo and Osaka prefectures in Japan were collected during 2002. The MICs for nine antimicrobials: penicillin G, tetracycline, cefixime, ceftriaxone, levofloxacin, gatifloxacin, ciprofloxacin, moxifloxacin, and spectinomycin were determined for each isolate. All isolates were also tested for beta lactamase producing profiles.

RESULTS

Among the 87 isolates obtained, only one isolate was revealed to produce beta lactamase. MIC90 values for ciprofloxacin, levofloxacin, gatifloxacin, and moxifloxacin were over 8 microg/ml, over 8 microg/ml, 4 microg/ml, and 2 microg/ml, respectively. The proportion of isolates resistant to fluoroquinolones was over 60% (ciprofloxacin, 70.1%; levofloxacin, 65.5%; gatifloxacin, 70.1%). Chromosomally mediated penicillin and tetracycline resistance was identified in 12.6% and 33.3% of the isolates. MIC90 values for cefixime and ceftriaxone and were 0.5 microg/ml and 0.0063 microg/ml. All isolates were sensitive to ceftriaxone and 90.8% of them were sensitive to cefixime. MIC90 for spectinomycin was 32 microg/ml and all isolates were sensitive to it. Fluoroquinolone resistance correlated significantly with MICs for penicillin G but not tetracycline.

CONCLUSION

Ceftriaxone and spectinomycin demonstrated lower MICs and so are recommended for N gonorrhoeae. Susceptibilities of N gonorrhoeae should be monitored periodically by region.

Differential expression of mRNA for Th1 and Th2 cytokine-associated transcription factors and suppressors of cytokine signalling in peripheral blood mononuclear cells of patients with atopic dermatitis

Atopic dermatitis is characterized by Th2-dominant immunity. Recently many intracellular molecules have been reported to regulate cytokine expression and T cell differentiation. GATA-3 and T-box expressed in T cells (T-bet) are transcription factors that play a critical role in the development of Th2 and Th1 immunity, respectively. Suppressor of cytokine signalling (SOCS)-3 and SOCS-5, are negative regulators of the cytokine signalling induced by IL-12 and IL-4, respectively. Txk is a transcription factor that activates IFN-gamma gene directly. The present study was designed to identify intracellular molecules that are responsible for the pathogenesis and the imbalance of cytokines in atopic dermatitis. Semi-quantitative RT-PCR revealed that in peripheral blood mononuclear cells without any stimulation the levels of mRNA for GATA-3 and SOCS-3 were elevated, the levels of mRNA for Txk were depressed and the levels of mRNA for T-bet and SOCS-5 were comparable in patients with atopic dermatitis as compared with healthy controls. In addition, successful therapy normalized levels of mRNA for GATA-3 and Txk, although those for the others including IL-4, IL-5, IL-10, IL-13 and IFN-gamma did not change. Levels of Txk mRNA correlated with those of IFN-gamma, while the mRNA levels of the other regulators did not correlate with those of any of the cytokines. These results suggest GATA-3 and Txk might be involved in skin lesions, while SOCS-3 might be associated with an imbalance of cytokines that is difficult to normalize in atopic dermatitis.

Biological activities of Bacteroides forsythus lipoproteins and their possible pathological roles in periodontal disease

Bacteroides forsythus is a gram-negative, anaerobic, fusiform bacterium and is considered to be an etiological agent in periodontal disease. A lipoprotein fraction prepared from B. forsythus cells by Triton X-114 phase separation (BfLP) activated human gingival fibroblasts and a human monocytic cell line, THP-1, to induce interleukin-6 production and tumor necrosis factor alpha production. BfLP was found to be capable of inducing nuclear factor-kappaB translocation in human gingival fibroblasts and THP-1 cells. By using Chinese hamster ovary K1 cells transfected with Toll-like receptor genes together with a nuclear factor-kappaB-dependent CD25 reporter plasmid, it was found that signaling by BfLP was mediated by Toll-like receptor 2 but not by CD14 or Toll-like receptor 4. BfLP induced apoptotic cell death in human gingival fibroblasts, KB cells (an oral epithelial cell line), HL-60 cells (a human myeloid leukemia cell line), and THP-1 cells but not in MOLT4 cells (a T-cell leukemia cell line). Caspase-8, an initiator caspase in apoptosis, was found to be activated in these cells in response to BfLP stimulation. Thus, this study suggested that BfLP plays some etiological roles in oral infections, especially periodontal disease, by induction of cell activation or apoptosis.