Correction: Hokynar, K. et al. Chlamydia-Like Organisms (CLOs) in Finnish Ixodes ricinus Ticks and Human Skin. Microorganisms 2016, 4, 28.

The authors wish to make the following modification to this paper [...].

Chlamydia-Like Organisms (CLOs) in Finnish Ixodes ricinus Ticks and Human Skin.

Ticks carry several human pathogenic microbes including Borreliae and Flavivirus causing tick-born encephalitis. Ticks can also carry DNA of Chlamydia-like organisms (CLOs). The purpose of this study was to investigate the occurrence of CLOs in ticks and skin biopsies taken from individuals with suspected tick bite. DNA from CLOs was detected by pan-Chlamydiales-PCR in 40% of adult ticks from southwestern Finland. The estimated minimal infection rate for nymphs and larvae (studied in pools) was 6% and 2%, respectively. For the first time, we show CLO DNA also in human skin as 68% of all skin biopsies studied contained CLO DNA as determined through pan-Chlamydiales-PCR. Sequence analyses based on the 16S rRNA gene fragment indicated that the sequences detected in ticks were heterogeneous, representing various CLO families; whereas the majority of the sequences from human skin remained "unclassified Chlamydiales" and might represent a new family-level lineage. CLO sequences detected in four skin biopsies were most closely related to "uncultured Chlamydial bacterium clones from Ixodes ricinus ticks" and two of them were very similar to CLO sequences from Finnish ticks. These results suggest that CLO DNA is present in human skin; ticks carry CLOs and could potentially transmit CLOs to humans.

The effects of low-intensity pulsed ultrasound on bioabsorbable self-reinforced poly L-lactide screws.

The effects of low-intensity pulsed ultrasound on the mechanical and molecular properties of self-reinforced poly L-lactide (SR-PLLA) screws were studied in vitro. SR-PLLA screws of 4.5 mm diameter were exposed on low-intensity ultrasound for 1, 3. 6, 9, and 12 weeks. After exposure, the bending strength, shear strength, and molecular weight were investigated. There were no differences in the investigated properties between the ultrasound exposure and control groups. We found no evidence that low-intensity ultrasound has any effect on the mechanical or molecular properties of SR-PLLA screws in vitro. The present results suggest that biodegradable SR-PLLA fixation devices are compatible with low-intensity ultrasound in vitro.

A long-term clinical study on dislocated ankle fractures fixed with self-reinforced polylevolactide (SR-PLLA) implants.

Sixteen patients with dislocated ankle fractures fixed between 1988 and 1991 with self-reinforced poly(L-lactide; SR-PLLA) screws and/or rods were followed up after 8.6 to 11.7 years (mean 9.6 years) at the Department of Orthopaedics and Traumatology, Helsinki University Central Hospital. In all patients accurate reduction of the fractures was retained and uneventful bony union was achieved. Good or excellent long-term functional results were observed in 15 out of 16 patients. One patient had post-traumatic osteoarthritis. In 5 patients, a late tissue reaction was observed over an extruding screw head with mild symptoms, which led to removal of small palpable masses. There were two superficial wound infections, one after a primary operation and one caused by a late tissue reaction after an operation. The correct operative technique, where all extruding extraosseous SR-PLLA material should be removed during the primary operation, should be followed.

Fixation of experimental osteotomies with bioabsorbable SR-polylactide-polyglycolide (80/20) polymeric rods.

Self-reinforced polylactide-polyglycolide (80/20) composite rods, 2 mm in diameter and 36 mm in length, were implanted into the dorsal subcutaneous tissue of 20 rabbits. Osteotomies of the distal femur were fixed with these rods (2x15 mm) in the rabbits. The follow-up times varied from 3 to 104 weeks. After sacrifice, three-point bending and shear tests and molecular weight measurements were performed for subcutaneously placed rods. Radiological, histological, microradiographic, oxytetracycline-fluorescence, and histomorphometrical studies of the osteotomized and intact control femora were performed. After 6 weeks the mechanical properties had decreased significantly, but osteotomies had healed uneventfully. The present investigation showed that the mechanical strength and fixation properties of SR-Polylactide-glycolide (80/20) rods are suitable for fixation of cancellous bone osteotomies in rabbits provided that the operative technique is correct. The present article is the first report on the application of these rods for fixation of cancellous bone osteotomies.

The effect of low-intensity pulsed ultrasound on bone healing in SR-PLLA rod fixed experimental distal femur osteotomy in rat.

The effects of low-intensity pulsed ultrasound (30 mW/cm2) were investigated in experimental cancellous bone fracture healing in bioabsorbable self-reinforced poly-L-lactide (SR-PLLA) rod fixed distal femur osteotomy in rats. A transverse transcondylar osteotomy was fixed with one SR-PLLA rod in 32 male Wistar rats of the age of 20 weeks. Half of the rats had a daily 20-min ultrasound exposure for three weeks. The follow-up times were three, six, and 12 weeks. Radiographical, histological, microradiographical, oxytetracycline labeling, and histomorphometrical analyses were performed. No foreign-body reactions were noted. The biocompatibility of SR-PLLA and ultrasound was found to be good. In the radiological and histological assessments there was a slight tendency for enhanced healing in the ultrasound group at three weeks, but at six and 12 weeks no differences were observed. The histomorphometrical and oxytetracycline labeling analyses showed that ultrasound exposure had no significant effects on bone healing. The present study shows that there were no obvious findings to support the hypothesis that low-intensity pulsed ultrasound enhances bone healing in self-reinforced poly-L-lactide (SR-PLLA) rod fixed experimental metaphyseal distal femur osteotomy in rats. The observed good biocompatibility provides a safe starting-point for clinical trials on bioabsorbable fixation combined with low-intensity ultrasound.

Bioabsorbable screw fixation for the treatment of ankle fractures.

BACKGROUND: Self-reinforced poly(L/dL)lactide 70:30 (SR-PLA70) retains its strength in bone for 24 weeks, whereas self-reinforced poly-L-lactide (SR-PLLA) retains its strength for over 36 weeks. In this prospective randomized study, bioabsorbable 4.5-mm SR-PLA70 screws were compared with SR-PLLA screws in the treatment of displaced ankle fractures in adults. METHODS: Sixty-two patients with ankle fractures needing operative treatment were randomized into two groups. Comminuted fractures needing plating were excluded. In total 54 of 62 patients were followed up for 1 year by clinical evaluation, radiographs, and Olerud-Molander score. RESULTS: The study groups differed significantly only in the mean duration of sick leave (SR-PLA70, 60 days; SR-PLLA, 65 days; P = 0.02). At the 1-year follow-up, syndesmotic ossification was more common in the SR-PLA70 group (5 versus 1 patient, not significant). Radiologically, the screw channel had not disappeared in any of the patients by the 1-year follow-up. CONCLUSIONS: Both implant types proved to have good biocompatibility. SR-PLA70 and SR-PLLA screws are suitable in selected cases for the fixation of ankle fractures, but the mechanical stability of the fixation has to be carefully monitored perioperatively.

Bioportfolio: lifelong persistence of variant and prototypic erythrovirus DNA genomes in human tissue.

Human erythrovirus is a minute, single-stranded DNA virus causing many diseases, including erythema infectiosum, arthropathy, and fetal death. After primary infection, the viral genomes persist in solid tissues. Besides the prototype, virus type 1, two major variants (virus types 2 and 3) have been identified recently, the clinical significance and epidemiology of which are mostly unknown. We examined 523 samples of skin, synovium, tonsil, or liver (birth year range, 1913-2000), and 1,640 sera, by qualitative and quantitative molecular assays for the DNA of human erythroviruses. Virus types 1 and 2 were found in 132 (25%) and 58 (11%) tissues, respectively. DNA of virus type 1 was found in all age groups, whereas that of type 2 was strictly confined to those subjects born before 1973 (P < 0.001). Correspondingly, the sera from the past two decades contained DNA of type 1 but not type 2 or 3. Our data suggest strongly that the newly identified human erythrovirus type 2 as well as the prototype 1 circulated in Northern and Central Europe in equal frequency, more than half a century ago, whereafter type 2 disappeared from circulation. Type 3 never attained wide occurrence in this area during the past > or =70 years. The erythrovirus DNA persistence in human tissues is lifelong and represents a source of information about our past, the Bioportfolio, which, at the individual level, provides a registry of one's infectious encounters, and at the population level, a database for epidemiological and phylogenetic analyses.

The effect of low intensity ultrasound and bioabsorbable self-reinforced poly-L-lactide screw fixation on bone in lateral malleolar fractures.

INTRODUCTION: There are no previous reports of low intensity pulsed ultrasound therapy in connection with bioabsorbable fracture fixation. In this randomised, prospective, double-blind and placebo-controlled study, the effects of ultrasound on bone mineral density and bone healing were examined in lateral malleolar fractures fixed with a bioabsorbable self-reinforced poly-L-lactide screw (SR-PLLA). MATERIALS AND METHODS: Thirty adult patients with SR-PLLA screw-fixed lateral malleolar fracture underwent ultrasound therapy 20 min daily for 6 weeks. Half of the patients were provided randomly with a sham ultrasound device. Bone mineral density and bone healing were assessed by dual-energy X-ray absorptiometry (DXA) and by radiographs. RESULTS: Bone mineral density of the fractured lateral malleolus tended to increase slightly during 12 weeks of follow-up. The increase was symmetrical and statistically non-significant between the ultrasound and non-ultrasound group. All the fractures healed uneventfully. The biocompatibility of the bioabsorbable SR-PLLA fixation device and low intensity pulsed ultrasound was good. Despite the slight tendency for more frequent callus formation in the ultrasound group, no statistically significant effect of low intensity pulsed ultrasound on lateral malleolar fracture healing could be observed. CONCLUSION: It was not possible to observe any statistically significant effect of low intensity pulsed ultrasound on lateral malleolar fracture healing in this study. Further studies are needed to examine the role of ultrasound therapy in the healing of fractures treated with bioabsorbable fixation devices.

Effect of ultrasound therapy on bone healing of lateral malleolar fractures of the ankle joint fixed with bioabsorbable screws.

BACKGROUND: We investigated the effect of low-intensity ultrasound on bone healing in bioabsorbable self-reinforced poly-L: -lactic acid (SR-PLLA) screw-fixed lateral malleolar fractures. The study design was prospective, randomized, double-blind, and placebo-controlled. METHODS: A total of 22 fractures were fixed with one SR-PLLA screw. All the patients were instructed to use an ultrasound device 20 min daily for 42 days without knowing whether it was active or inactive. Eleven patients had active and eleven sham ultrasound devices. The causes of error during treatment with head module placement and attachment to the convex surface of the lateral distal fibula were minimized by careful targeting and using coupling gel. Radiological fracture healing was assessed by radiographs and multidetector computed tomography (CT) scans in a blinded manner by a radiologist and orthopedic surgeons. RESULTS: The overall compliance to the daily ultrasound treatments was good. All wounds healed uneventfully, and no foreign body reactions were observed. No difference was observed between the groups regarding either fracture line visualization or callus formation assessed by plain radiographs. In the CT images at 9 weeks, the share of the endosteal united fracture line compared to the non-united fracture line was slightly higher in the active ultrasound device group than in the sham ultrasound device group, but the difference was not statistically significant. CONCLUSION: The study indicates that the biocompatibility of ultrasound therapy and bioabsorbable SR-PLLA screw fixation is good. There was no obvious effect of low-intensity ultrasound on lateral malleolar fracture healing. However, the relatively small number of patients must be kept in mind when interpreting our results. It is also important to limit any conclusions based on the present study to malleolar fractures fixed with the SR-PLLA screw.

Stress reaction in the carpal bones caused by breakdancing.

Stress reactions in the bones of the lower extremities are a common finding on magnetic resonance (MR) imaging. The primary finding in the bone marrow is nonspecific edema without any visible fracture line that may even mimic tumor or infection. Continuing stress may eventually lead to a stress fracture. We present the case of a stress reaction related to breakdancing in a less typical localization, in the triquetral bone in the wrist.

Healing of subcapital femoral osteotomies fixed with self-reinforced poly-L-lactide screws: an experimental long-term study in sheep.

Subcapital femoral osteotomies of ten young adult sheep were fixed with two bioabsorbable, self-reinforced, poly- L-lactide (SR-PLLA) lag screws of 4.5 mm in diameter. At 3 weeks radiographs were taken to check the reduction and fixation achieved. After follow-up periods of 12 weeks, 1 year and 3 years with three sheep in each group, and of 7 years and 4 months with one sheep, the sheep were killed, and the healing of the osteotomies, degradation and tissue response of the implants were examined radiographically, histologically and microradiographically. All osteotomies healed with a firm bony union. There was no dislocation or wound infection. Histologically, there was no marked tissue response in the bone tissue. At 12 weeks the implants were grossly intact, at 1 year granulation tissue and new bone formation had started to penetrate into the implant, and at 3 years the implant area was mostly replaced by connective tissue and new bone, but implant material was still seen as little islands surrounded by some lymphocytes. At 7 years and 4 months, the implant material had been degraded and replaced by tight bone. Self-reinforced poly- L-lactide lag screws seem to possess adequate mechanical properties and good biocompatibility for this demanding fixation.

A new parvovirus genotype persistent in human skin.

Parvovirus B19 is the exclusive human pathogen of the Erythrovirus genus. In classical view, the B19 DNA sequence shows little variability, with no disease-specific or tissue type specific associations. We examined skin biopsies from patients with B19-unrelated skin disease or from constitutionally healthy adults by polymerase chain reaction assays for four different genomic regions of the B19 virus. Sequencing showed that the skin-derived viral DNA differed within the protein-coding region from the B19 reference sequences by 10.8% and from the V9 variant by 8.6% and within the noncoding region (covering nucleotides 189-435 of the promoter region) by 26.5 and 17.2%, respectively. Despite this sequence difference, the promoter region was shown by a luciferase gene expression assay to be biologically active. We have detected a new B19 virus genotype, K71, which differs extensively from the known B19-virus genotypes and is persistently carried in human skin.