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Background Rapidly instituted antimicrobial therapy is important in severe infections, and reduced time to the antimicrobial susceptibility testing (AST) report is thus of importance. Disc diffusion (DD) is a cheap, rapidly adaptable, flexible and comprehensive method for phenotypic AST. Previous studies have shown that early reading of inhibition zones for non-fastidious species is possible. Objectives To evaluate zone reading after short incubation of DD in Haemophilus influenzae (n  = 73) and Streptococcus pneumoniae (n  = 112). Methods The readability was evaluated and susceptibility interpretation (SIR) was performed, using the EUCAST 18 ± 2 h incubation breakpoint table (version 12.0), after 6 and 8 h of incubation. Categorical agreement (CA) and error rates were calculated using standard DD and broth microdilution as reference. Results The proportion of readable zones in H. influenzae was 19% (6 h) and 89% (8 h). The CA was 98% after 8 h. The corresponding readability in S. pneumoniae was 63%/98% and CA was 95%/97% after 6 and 8 h, respectively. Early reading of the screening discs (benzylpenicillin 1 unit in H. influenzae and oxacillin 1 µg in S. pneumoniae) correctly identified 18/22 of the H. influenzae isolates and all the readable S. pneumoniae isolates with reduced β-lactam susceptibility. For non-β-lactam agents, very major errors were most common for quinolones in S. pneumoniae. Introduction of areas of technical uncertainty (ATUs) reduced the error rate to ≤1.1%. Conclusions We conclude that shortened incubation is feasible for H. influenzae and S. pneumoniae. To reduce the risk of false categorization a buffer zone (i.e. ATU) near the breakpoints must be used. [ABSTRACT FROM AUTHOR]

Abstract: NOX5 is a ROS-generating NADPH oxidase which contains an N-terminal EF-hand region and can be activated by cytosolic Ca2+ elevations. However the C-terminal region of NOX5 also contains putative phosphorylation sites. In this study we used HEK cells stably expressing NOX5 to analyze the size and subcellular localization of the NOX5 protein, its mechanisms of activation, and the characteristics of the ROS released. We demonstrate that NOX5 can be activated both by the protein kinase C activating phorbol esther PMA and by the Ca2+ ionophore ionomycin. The PMA- but not the ionomycin-dependent activation can be inhibited by protein kinase C inhibitors. NOX5 activity is inhibited by submicromolar concentrations of diphenyl iodonium (DPI), but not by apocynin. Western blot analysis showed a lower (∼70kDa) than expected (82kDa) molecular mass. Two arguments suggest that NOX5 is at least partially expressed on the plasma membrane: (i) the membrane-impermeant superoxide was readily detected by extracellular probes, and (ii) immunofluorescent labeling of NOX5 detected a fraction of the NOX5 protein at the plasma membrane. In summary, we demonstrate that NOX5 can be found intracellularly and at the cell surface. We also describe that it can be activated through protein kinase C, in addition to its Ca2+ activation. [Copyright &y& Elsevier]

Presents research which showed the generation of electron currents by the NADPH oxidase in human eosinophil granulocytes. Electron transport not usually found in plasma membrane of eukaryotic cells, except for the phagocyte NADPH oxidase; Importance of NADPH oxidase for host defense; Use of whole-cell patch-clamp technique; Possible role of NADPH oxidase in generation of electron currents across plasma membrane.

We have investigated Ca2+-induced exocytosis from human neutrophils using the whole cell patch­clamp capacitance technique. Microperfusion of Ca2+ buffer solutions (<30 nM to 5 mM free Ca2+) through the patch­clamp pipette revealed a biphasic activation of exocytosis by Ca2+. The first phase was characterized by high affinity (1.5–5 μM) and low apparent cooperativity (≤2) for Ca2+, and the second phase by low affinity (∼100 μM) and high cooperativity (>6). Only the second phase was accompanied by loss of myeloperoxidase, suggesting that the low-affinity exocytosis reflected release of peroxidase-positive (primary) granules, while the high-affinity exocytosis reflected release of peroxidase­negative (secondary and tertiary) granules. At submaximal Ca2+ concentrations, only a fraction of a given granule population was released. This submaximal release cannot simply be explained by Ca2+ modulation of the rate of exocytosis, and it suggests that the secretory response of individual cells is adjusted to the strength of the stimulus. The Ca2+ dependence of the high- and low-affinity phases of neutrophil exocytosis bears a resemblance to endocrine and neuronal exocytosis, respectively. The occurrence of such high- and low-affinity exocytosis in the same cell is novel, and suggests that the Ca2+ sensitivity of secretion is granule-, rather than cell-specific. [ABSTRACT FROM AUTHOR]

Objective: Fecal microbiota transplantation (FMT) is a highly effective treatment for Clostridioides difficile infection (CDI). However, the fecal transplant's causal components translating into clearance of the CDI are yet to be identified. The commensal bacteria Faecalibacterium prausnitzii may be of great interest in this context, since it is one of the most common species of the healthy gut microbiota and produces metabolites with anti-inflammatory properties. Although there is mounting evidence that F. prausnitzii is an important regulator of intestinal homeostasis, data about its role in CDI and FMT are relatively scarce. Methods: Stool samples from patients with recurrent CDI were collected to investigate the relative abundance of F. prausnitzii before and after FMT. Twenty-one patients provided fecal samples before the FMT procedure, at 2 weeks post-FMT, and at 2–4 months post-FMT. The relative abundance of F. prausnitzii was determined using quantitative polymerase chain reaction. Results: The abundance of F. prausnitzii was elevated in samples (N = 9) from donors compared to pre-FMT samples (N = 15) from patients (adjusted P<0.001). No significant difference in the abundance of F. prausnitzii between responders (N = 11) and non-responders (N = 4) was found before FMT (P = 0.85). In patients with CDI, the abundance of F. prausnitzii significantly increased in the 2 weeks post-FMT samples (N = 14) compared to the pre-FMT samples (N = 15, adjusted P<0.001). The increase persisted 2–4 months post-FMT (N = 15) compared to pre-FMT samples (N = 15) (adjusted P<0.001). Conclusions: FMT increases the relative abundance of F. prausnitzii in patients with recurrent CDI, and this microbial shift remains several months later. The baseline abundance of F. prausnitzii in donors or recipients was not associated with future treatment response, although a true predictive capacity cannot be excluded because of the limited sample size. Further studies are needed to discern whether F. prausnitzii plays an active role in the resolution of CDI. [ABSTRACT FROM AUTHOR]

The modern wound dressing is produced to absorb fluid and protect against external contamination. The choice of which wound dressing to apply after surgery is usually based on local tradition. There are various impervious dressings on the market. Even if the wound is sterile before application, there will be subsequent recolonisation of skin microbiota. Previous studies suggest that a high bacterial load on the skin hampers wound healing and might be a risk for SSI.The aim was to compare bacterial recolonisation on the shoulder under three different wound dressings, 48 h after sterile preparation of the skin as in preparation for surgery.In 25 healthy volunteers, a standard pre-surgical skin disinfection for a deltopectoral incision was made on the left shoulder with 0.5% chlorhexidine solution in 70% ethanol. Three different wound dressings were then placed on the shoulder, and 48 h later the skin beneath each dressing was swabbed, subsequently cultured and bacterial density analysed using viable count.The bacterial recolonisation under air-dry (gauze) dressing was significantly lower (p = .0001) compared to semipermeable and occlusive wound dressings.Choosing a less permeable wound dressing may lead to an increased bacterial load on the skin during the first 48 h after surgery. [ABSTRACT FROM AUTHOR]

Progressive multifocal leukoencephalopathy (PML), caused by reactivation of JC-virus is a relatively rare complication seen in patients with compromised immune system. There are no evidence-based treatment available and prognosis is poor. Withdrawal of immunosuppressant can result in further neurological deterioration and for patients with solid organ transplantations, fatal graft rejection. We report a 52-year-old women that presented with seizures within 1 month after heart transplantation. Initial diagnosis was vascular disease. After clinical deterioration 10 months after transplantation, further examinations led to the diagnosis. Minimizing tacrolimus, to a concentration of 2 ng/ml, and extensive physical therapy has improved the physical capacity of the patient. The patient has now been clinically stable for 4 years and extended survival for 5 years. This case adds to the limited adult cases of PML within the population of heart transplant recipients and the need for increased awareness to minimize diagnosis delay. [ABSTRACT FROM AUTHOR]

Magnetotactic bacteria (MTB), ubiquitous in soil and fresh and saltwater sources have been identified in the microbiome of humans and many animals. MTB endogenously produce magnetic nanocrystals enabling them to orient and navigate along geomagnetic fields. Similar magnetite deposits have been found throughout the tissues of the human brain, including brain regions associated with orientation such as the cerebellum and hippocampus, the origins of which remain unknown. Speculation over the role and source of MTB in humans, as well as any association with the brain, remain unanswered. We performed a metagenomic analysis of the gut microbiome of 34 healthy females as well as grey matter volume analysis in magnetite-rich brain regions associated with orientation and navigation with the goal of identifying specific MTB that could be associated with brain structure in orientation and navigation regions. We identified seven MTB in the human gut microbiome: Magnetococcus marinus, Magnetospira sp. QH-2, Magnetospirillum magneticum, Magnetospirillum sp. ME-1, Magnetospirillum sp. XM-1, Magnetospirillum gryphiswaldense, and Desulfovibrio magneticus. Our preliminary results show significant negative associations between multiple MTB with bilateral flocculonodular lobes of the cerebellum and hippocampus (adjusted for total intracranial volume, uncorrected P<0.05). These findings indicate that MTB in the gut are associated with grey matter volume in magnetite-rich brain regions related to orientation and navigation. These preliminary findings support MTB as a potential biogenic source for brain magnetite in humans. Further studies will be necessary to validate and elucidate the relationship between these bacteria, magnetite concentrations, and brain function. [ABSTRACT FROM AUTHOR]

Phagolysosome fusion and granule exocytosis in neutrophils are calcium-dependent processes. The calcium requirements vary between granule types, suggesting the presence of different calcium sensors. The synaptotagmins, a family of calcium-binding proteins, previously shown to participate in vesicle fusion and vesicle recycling in excitable cells, are putative calcium-sensors of exocytosis in excitable cells. In this study, we show that synaptotagmin II is present in human neutrophils and may participate in phagocytic and in exocytotic processes. In protein extracts from human neutrophils, we identified synaptotagmin II by Western blot as an 80 kDa protein. Subcellular fractionation revealed that synaptotagmin II was associated with the specific granules. In fMLP-stimulated cells, synaptotagmin II translocated to the plasma membrane. This correlated with the upregulation of complement receptor 3 (CR 3), reflecting the translocation of specific granules to the cell surface. Synaptotagmin II also translocated to the phagosome after complement-mediated phagocytosis in the presence of calcium. LAMP-1 translocated in parallel but probably was located to another subcellular compartment than synaptotagmin II. Under calcium-reduced conditions, neither synaptotagmin II nor LAMP-1 translocated to the phagosome. We therefore suggest a role for synaptotagmin II as calcium-sensor during phagocytosis and secretion in neutrophils. [Copyright &y& Elsevier]

Objectives: When bloodstream infections are caused by resistant bacteria, rapid antimicrobial susceptibility testing (RAST) is important for adjustment of therapy. The EUCAST RAST method, directly from positive blood cultures, was validated in a multi-laboratory study in Europe.Methods: RAST was performed in 40 laboratories in northern Europe (NE) and 15 in southern Europe (SE) from clinical blood cultures positive for Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus or Streptococcus pneumoniae. Categorical results at 4, 6 and 8 h of incubation were compared with results for EUCAST standard 16-20 h disc diffusion. The method, preliminary breakpoints and the performance of the laboratories were evaluated.Results: The total number of isolates was 833/318 in NE/SE. The number of zone diameters that could be read (88%, 96% and 99%) and interpreted (70%, 81% and 85%) increased with incubation time (4, 6 and 8 h). The categorical agreement was acceptable, with total error rates in NE/SE of 2.4%/4.9% at 4 h, 1.1%/3.5% at 6 h and 1.1%/3.3% at 8 h. False susceptibility at 4, 6 and 8 h of incubation was below 0.3% and 1.1% in NE and SE, respectively, and the corresponding percentages for false resistance were below 1.9% and 2.8%. After fine-tuning breakpoints, more zones could be interpreted (73%, 89% and 93%), with only marginally affected error rates.Conclusions: The EUCAST RAST method can be implemented in routine laboratories without major investments. It provides reliable antimicrobial susceptibility testing results for relevant bloodstream infection pathogens after 4-6 h of incubation. [ABSTRACT FROM AUTHOR]

A typical clinical symptom of human norovirus infection is projectile vomiting. Although norovirus RNA and viral particles have been detected in vomitus, infectivity has not yet been reported. We detected replication-competent norovirus in 25% of vomit samples with a 13-fold to 714-fold increase in genomic equivalents, confirming infectious norovirus. [ABSTRACT FROM AUTHOR]

Lyme borreliosis (LB), caused by spirochetes belonging to the Borrelia burgdorferi sensu lato complex, is the most common tick-borne infection in Europe. Laboratory diagnosis of LB is mainly based on the patients' medical history, clinical signs and symptoms in combination with detection of Borrelia-specific antibodies where indirect enzyme-linked-immunosorbent assay (ELISA) is the most widely used technique. The objective of the study was to evaluate and compare the diagnostic accuracy (sensitivities and specificities) of serological tests that are currently in use for diagnosis of LB in clinical laboratories in Northern Europe, by use of a large serum panel. The panel consisted of 195 serum samples from well-characterized and classified patients under investigation for clinically suspected LB (n = 59) including patients with Lyme neuroborreliosis, Lyme arthritis, acrodermatitis chronica atrophicans, erythema migrans or other diseases (n = 112). A total of 201 serum samples from healthy blood donors were also included. The panel (396 serum samples altogether) was sent to 12 clinical laboratories (using five different ELISA methods) as blinded for group affiliation and the laboratories were asked to perform serological analysis according to their routine procedure. The results from the study demonstrated high diagnostic concordance between the laboratories using the same diagnostic assay and lower diagnostic concordance between laboratories using different diagnostic assays. For IgG, the results were in general rather homogenous and showed an average sensitivity of 88% (range 85–91%) compared to IgM which showed lower average sensitivity of 59% (range 50–67%) and more heterogeneous results between assays and laboratories. [ABSTRACT FROM AUTHOR]

Summary: Objectives: To identify the epidemiology and antifungal susceptibilities of Candida spp. among blood culture isolates to identify the epidemiology and antifungal susceptibilities of Candida spp. among blood culture isolates in Sweden. Methods: The study was a retrospective, observational nationwide laboratory‐based surveillance for fungaemia and fungal meningitis and was conducted from September 2015 to August 2016. Results: In total, 488 Candida blood culture isolates were obtained from 471 patients (58% males). Compared to our previous study, the incidence of candidaemia has increased from 4.2/100 000 (2005‐2006) to 4.7/100 000 population/year (2015‐2016). The three most common Candida spp. isolated from blood cultures were Candida albicans (54.7%), Candida glabrata (19.7%) and species in the Candida parapsilosis complex (9.4%). Candida resistance to fluconazole was 2% in C. albicans and between 0% and 100%, in non‐albicans species other than C. glabrata and C. krusei. Resistance to voriconazole was rare, except for C. glabrata, C. krusei and C. tropicalis. Resistance to anidulafungin was 3.8% while no Candida isolate was resistant to amphotericin B. Conclusions: We report an overall increase in candidaemia but a minor decrease of C. albicans while C. glabrata and C. parapsilosis remain constant over this 10‐year period. [ABSTRACT FROM AUTHOR]

The purpose of this study was to assess the seroprevalence of C6 ELISA antibodies in healthy blood donors in Kalmar County, Sweden, in relation to age, sex and time of year (peak season vs off season). In addition, we wanted to assess serological status over time in a group of C6 ELISA seropositive blood donors. Sera were collected from 273 (131 women, 142 men) blood donors in autumn 2011 and 300 (144 women, 156 men) in winter 2014. All sera were analysed in the C6 ELISA and the results were interpreted according to the manufacturer′s instructions. The seroprevalence was 22% (females 16%, males 28%) in 2011 and 24% (females 15%, males 33%) in 2014. The seroprevalence was significantly higher in males and increased with age. The highest seroprevalence was observed among elderly men, 60-70 years old (46% in 2011 and 52% in 2014). No significant difference was detected in seropositivity between the samples collected in winter and autumn. All (34/34) seropositive blood donors followed over time remained seropositive at follow-up after 22-29 months. C6 ELISA seroprevalence in healthy blood donors is high in Kalmar County, thereby reducing the specificity of a positive test result regarding the clinical diagnosis of Lyme borreliosis ( LB). Although C6 seroprevalence appears not to be affected by seasonal sample time, it varies greatly with age and sex. A careful evaluation of pre-test probability is therefore of the utmost importance in the clinical diagnosis of LB, especially in elderly men. We suggest that colleagues in other endemic regions also consider initiating similar evaluations to optimize the laboratory and clinical diagnosis of LB in relation to age and sex. [ABSTRACT FROM AUTHOR]

National data from Denmark, Finland, Norway and Sweden demonstrate remarkable differences in candidaemia epidemiology. Only Denmark has reported a high incidence of 10 per 100 000 inhabitants and a species shift towards increased C. glabrata candidaemias. The reasons for this development remain unclear. The aim of this study was to explore possible contributing factors for the differences in Candida epidemiology in the Nordic countries. We used public data from 2011 from Denmark, Finland, Norway and Sweden on epidemiology, demographics, health facilities, predisposing risk factors, consumption of antimicrobial drugs and fungicides in agricultural industry. Only the prevalence of haematological malignancies ( P < 0.001) was significantly higher in Denmark compared to the other Nordic countries. The antibacterial drug use of metronidazole, piperacillin-tazobactam, ciprofloxacin, colistin and carbapenems, and antifungal use of fluconazole in humans ( P < 0.001), were significantly higher in Denmark compared to the other Nordic countries (all P < 0.001). Our findings suggest haematological malignancy, the use of certain antibacterial drugs and azoles in humans as possible contributing factors for the differences in Candida epidemiology. However, our results should be interpreted with caution due to the lack of long-term, case-specific data. Further studies are needed. [ABSTRACT FROM AUTHOR]

Herpes simplex virus 2 (HSV-2) is one of the most common sexually transmitted infections globally, with a very high prevalence in many countries. During HSV-2 infection, viral particles become coated with complement proteins and antibodies, both present in genital fluids, which could influence the activation of immune responses. In genital mucosa, the primary target cells for HSV-2 infection are epithelial cells, but resident immune cells, such as dendritic cells (DCs), are also infected. DCs are the activators of the ensuing immune responses directed against HSV-2, and the aim of this study was to examine the effects opsonization of HSV-2, either with complement alone or with complement and antibodies, had on the infection of immature DCs and their ability to mount inflammatory and antiviral responses. Complement opsonization of HSV-2 enhanced both the direct infection of immature DCs and their production of new infectious viral particles. The enhanced infection required activation of the complement cascade and functional complement receptor 3. Furthermore, HSV-2 infection of DCs required endocytosis of viral particles and their delivery into an acid endosomal compartment. The presence of complement in combination with HSV-1- or HSV-2-specific antibodies more or less abolished HSV-2 infection of DCs. Our results clearly demonstrate the importance of studying HSV-2 infection under conditions that ensue in vivo, i.e., conditions under which the virions are covered in complement fragments and complement fragments and antibodies, as these shape the infection and the subsequent immune response and need to be further elucidated. [ABSTRACT FROM AUTHOR]

Background The aim of this study was to evaluate diagnostic tests in order to introduce a diagnostic strategy to identify the most common gram-positive bacteria (pneumococci, enterococci, β- haemolytic streptococci and S. aureus) found in blood cultures within 6 hours after signalling growth. Methods The tube coagulase test was optimized and several latex agglutination tests were compared and evaluated before a validation period of 11 months was performed on consecutive positive blood culture patient samples from Kalmar County Hospital, Sweden. Results During the validation period 150 (91%) of a total of 166 gram-positive cocci ( 119 in clusters, 45 in chains or pairs and 2 undefined morphology) were correctly identified as S. aureus, CoNS, Pneumococci, Enterococci or group A streptococci (GAS), group B streptococci (GBS), group G streptococci (GGS) within 6 hours with a minimal increase in work-load and costs. The remaining samples (9%) were correctly identified during the next day. No samples were incorrectly grouped with this diagnostic strategy and no patient came to risk by early reporting. Conclusion A simple strategy gives reliable and cost-effective reporting of >90% of the most common gram-positive cocci within 6 hours after a blood cultures become positive. The high specificity of the tests used makes preliminary reports reliable. The reports can be used to indicate the focus of infection and not the least, support faster administration of proper antimicrobial treatment for patients with serious bacterial infections. [ABSTRACT FROM AUTHOR]

Abstract: NADPH oxidase Nox4 is expressed in a wide range of tissues and plays a role in cellular signaling by providing reactive oxygen species (ROS) as intracellular messengers. Nox4 oxidase activity is thought to be constitutive and regulated at the transcriptional level; however, we challenge this point of view and suggest that specific quinone derivatives could modulate this activity. In fact, we demonstrated a significant stimulation of Nox4 activity by 4 quinone derivatives (AA-861, tBuBHQ, tBuBQ, and duroquinone) observed in 3 different cellular models, HEK293E, T-REx™, and chondrocyte cell lines. Our results indicate that the effect is specific toward Nox4 versus Nox2. Furthermore, we showed that NAD(P)H:quinone oxidoreductase (NQO1) may participate in this stimulation. Interestingly, Nox4 activity is also stimulated by reducing agents that possibly act by reducing the disulfide bridge (Cys226, Cys270) located in the extracellular E-loop of Nox4. Such model of Nox4 activity regulation could provide new insight into the understanding of the molecular mechanism of the electron transfer through the enzyme, i.e., its potential redox regulation, and could also define new therapeutic targets in diseases in which quinones and Nox4 are implicated. [Copyright &y& Elsevier]

Aichi virus (AiV), genus Kobuvirus, family Picornaviridae, is associated with gastroenteritis in humans. Previous studies have shown high seroprevalence but low incidence (0.9-4.1%) in clinical samples. We report here the first detection of AiV in Sweden. Two hundred twenty-one specimens from hospitalized patients with diarrhea, who were negative for other enteric viruses, were included in the study. AiV were detected in three specimens, all from elderly patients. Phylogenetic analysis revealed that the three Swedish isolates belonged to genotype A and were genetically closest to European and Asian strains of AiV. [ABSTRACT FROM AUTHOR]

Abstract: Reactive oxygen species (ROS) and deposition of cleaved products of amyloid precursor protein (APP) are thought to contribute to neuronal loss observed in Alzheimer''s disease (AD). The relationship between these factors was studied in a neuroblastoma and microglia co-culture system. Overexpression of wild-type APP (APP-wt) or APP with three mutations typical of familial AD (APP-3m) in SH-SY5Y neuroblastoma cells did not directly alter their morphology, growth rate, cell cycle or H2O2 sensitivity. In a co-culture of APP-wt neuroblastoma cells with microglia, microglial cells generated ROS and neuronal cells died. The cell death was more pronounced in APP-3m-expressing neurons. Neuroblastoma cell death was attenuated by ROS-scavengers and was dose-dependently inhibited by the NADPH oxidase inhibitor diphenyleneiodonium chloride (DPI). Macrophage cell lines behaved similarly to microglia in the co-culture model. However, a macrophage cell line deficient in the NADPH oxidase subunit, gp91phox, failed to kill neurons. These results suggest that APP-dependent microglia activation and subsequent ROS generation by the phagocyte NADPH oxidase play a crucial role in neuronal killing in a cellular model of AD. [Copyright &y& Elsevier]

In cases where antibody- and complement-mediated hyperacute rejection (HAR) of vascularized organ xenografts has been prevented, acute vascular rejection (AVR) and acute T cell-mediated rejection (ACR) cause graft destruction. Infiltration of leukocytes (innate and graft-primed T cells) into the graft execute the latter two rejection modalities. The leukocyte extravasation process, which is a prerequisite for graft infiltration, is governed by adhesion molecules, including the selectin, integrin and immunoglobulin protein families, and the chemokine protein family. The compatibility between porcine endothelial cell and human leukocyte adhesion molecules was investigated in dynamic adhesion and static transendothelial migration assays. The effect of human anti-pig antibodies on human leukocyte adhesion to, and transendothelial migration across, porcine endothelium was assessed under dynamic and static conditions, respectively. In contrast to previously published results, no difference in the ability of neutrophils to adhere to pig and human endothelium was observed. Furthermore, no evident quantitative or qualitative differences in the capacity of human and porcine endothelium to support transendothelial migration of human leukocytes (T, B and natural killer (NK) cells, monocytes, and neutrophils) could be detected. The presence of human anti-pig antibodies (Abs) modulated the migration of leukocytes across porcine endothelium, as well as neutrophil adhesion to porcine endothelium under conditions of flow. Antibodies specific for pig endothelial adhesion molecules can potentially be used as species (graft)-specific immunosuppressive reagents in order to prevent cellular organ xenograft rejection. [Copyright &y& Elsevier]

Broad-range amplification and sequencing of the 16S rRNA gene, directly from clinical samples, is a method that potentially allows detection of any cultivable or non-cultivable bacteria. However, the method is prone to false positive results due to PCR contamination. Another concern is the human DNA abundance compared to bacterial DNA in samples from sterile sites. Those factors may decrease the sensitivity and specificity of the assay and can complicate the analysis and interpretation of the results. The objective of this prospective study was to try to avoid the most common pitfalls, mentioned above, and develop a molecular 16S assay with a high clinical sensitivity and specificity. Fifty-six consecutive tissue samples from patients with suspected deep infections were extracted by 3 different DNA-extraction methods; two based on a principle of bacterial DNA enrichment, and one conventional DNA extraction method. We compared three primer pairs, including both conventional and DPO principle, targeting different variable regions of the 16S rRNA gene. Results from routine tissue culture were used as reference. Clinical data was recorded from patient charts and analyzed in parallel. Of a total of 56 samples, collected from 39 patients, 70% (39 samples) were assessed as true infections by analysis of clinical data. Bacterial enrichment extraction increased sensitivity from 54% to 72%. The 2 sets of primer pairs defining region V1-V3 and V3-V4, showed similar sensitivity, but DPO-primers resulted in better specificity, i.e. less contaminations. The primer pairs covering V1-V8 show significantly lower sensitivity (p <.001) than V1-V3 and V3-V4. Optimizing extraction protocols and choice of primers can increase the sensitivity and specificity of a molecular 16S-analysis, rendering a valuable complement to tissue culture. • 16S rRNA analysis can be improved by the choice of extraction technique and primers. • A more sensitive 16S rRNA method generates more contamination results than culture. • The 16S rRNA analysis is particularly valuable from abscesses and fluids. • Molecular detection of 16S rRNA can be a valuable complement to culture. [ABSTRACT FROM AUTHOR]

Abstract: Background: Hepatitis C diagnostics involve antibody screening and confirmation of current infection by detection of HCV RNA positivity. In screening instruments with fixed pipetting needle, there is a risk of sample carry-over contamination. Objectives: The aim of this study was to evaluate the risk of such contamination in a proposed clinical setting. Study design: In the present study, known HCV RNA positive (n =149) and negative (n =149) samples were analysed by anti-HCV Abbott in an Architect instrument in an alternating fashion in order to test for contamination. Results: In subsequent retesting of the previously HCV RNA-negative samples, six samples (4%) were positive by the Cobas Taqman assay with a maximum level of 33IU/mL. The results show that there is a risk for transfer of HCV in the Architect instrument but they also show that the levels of HCV RNA observed are low. Conclusions: We conclude that complementary HCV RNA testing on samples identified as anti-HCV positive by screening can be recommended because the complementary results are reliable in the majority of cases when either HCV RNA is negative or HCV RNA is positive with a level >1000IU/mL. In a minority of cases, with low HCV RNA after anti-HCV antibody screening, cross-contamination should be suspected and a new sample requested for HCV RNA testing. This strategy would reduce the need for obtaining a new sample from the vast majority of patients with a newly discovered HCV antibody positivity. [Copyright &y& Elsevier]

Background: The aim of this study was to evaluate diagnostic tests in order to introduce a diagnostic strategy to identify the most common gram-positive bacteria (pneumococci, enterococci, β-haemolytic streptococci and S. aureus) found in blood cultures within 6 hours after signalling growth.Methods: The tube coagulase test was optimized and several latex agglutination tests were compared and evaluated before a validation period of 11 months was performed on consecutive positive blood culture patient samples from Kalmar County Hospital, Sweden.Results: During the validation period 150 (91%) of a total of 166 gram-positive cocci (119 in clusters, 45 in chains or pairs and 2 undefined morphology) were correctly identified as S. aureus, CoNS, Pneumococci, Enterococci or group A streptococci (GAS), group B streptococci (GBS), group G streptococci (GGS) within 6 hours with a minimal increase in work-load and costs. The remaining samples (9%) were correctly identified during the next day. No samples were incorrectly grouped with this diagnostic strategy and no patient came to risk by early reporting.Conclusion: A simple strategy gives reliable and cost-effective reporting of >90% of the most common gram-positive cocci within 6 hours after a blood cultures become positive. The high specificity of the tests used makes preliminary reports reliable. The reports can be used to indicate the focus of infection and not the least, support faster administration of proper antimicrobial treatment for patients with serious bacterial infections. [ABSTRACT FROM AUTHOR]