Search

This paper presents simulation of a photovoltaic panel connected to a load through a boost converter. Due to the nonlinear characteristics of the PV panel and in order to increase its performance, reduce cost of the application and improve the efficiency of the photovoltaic system, maximum power point tracking algorithm is necessary. We present also an implementation of three maximum power point tracking algorithms: Perturb and Observe (P&O), Incremental Conductance (INC-COND) and Fractional Open Circuit Voltage (FOCV) which are widely studied and used in many researches papers. Experimental and simulation results are obtained using Matlab/Simulink software. The results show the efficiency of these MPPT algorithms in tracking the maximum power and its faster response to adapt to the change in irradiation condition.

In this paper, we present the study of the structural, mechanical, magneto-electronic and thermodynamic properties of the perovskite KBeO_3. The calculations were performed by the full potential augmented plane wave method, implemented in the WIEN2k code which is based on density functional theory, using generalized gradient approximation. The computed formation energy and elastic constants indicate the synthesizability and mechanical stability of KBeO_3. Moreover, our results showed that the latter is a half-metallic material with half-metallic gap of 0.67 eV and an integer magnetic moment of 3μB per unit cell. In addition, KBeO_3 maintains the half-metallic character under the pressure up to about 97 GPa corresponding to the predicted magnetic-phase transition pressure from ferromagnetic to non-magnetic state. The volume ratio V/V_0, bulk modulus, heat capacity, thermal expansion and the Debye temperature are analyzed using the quasi-harmonic Debye model.

Background: The incidence of TB among Inuit is the highest in Canada. A significantly shorter latent TB infection (LTBI) treatment with rifapentine and isoniazid once weekly for 12 weeks (3HP) is now available in limited settings in Canada. Methods: A prospective open -label 2-year observational postmarketing study was conducted introducing 3HP for the first time in Canada in Iqaluit followed by a program rollout in Qikiqtarjuaq, Nunavut. Results: A total of 247 people were offered 3HP, 102 in the Iqaluit postmarketing study and 145 in the Qikiqtarjuaq program roll out. Although statistical significance was not reached, more people who started treatment completed treatment in the 3HP group (Iqaluit, 60/73 (82.2%) and Qikiqtarjuaq, 89/115 (77.4%)) than in the historical control 9INHgroup (306/420 = 72.9%) (p = 0.2). Most of the adverse events in 3HP treated patients were associated with mild discomfort but no disruption of normal daily activity. Not drinking alcohol was associated with increased 3HP completion (OR 13.33, 95% CI, 2.27–78.20) as was not taking concomitant medications (OR 7.19, 95% CI, 1.47–35.30). Conclusions: The present study supports the feasibility and safety profile of 3HP for the treatment of LTBI in Nunavut.

BACKGROUND A comparative method of adding honey to culture media with and without starch was used to evaluate the role of amylases present in honey in enhancing its antibacterial activity. MATERIAL AND METHODS Three varieties of honey from different origins were tested for their antibacterial activity against a strain of Staphylococcus aureus using an agar incorporation technique. For each variety the Minimum Inhibitory Concentration (MIC) was determined by finding the plate with the lowest concentration of honey on which the strain would not grow. A solution of 10 % starch was used to add the given concentration to honey. An equivalent volume of water was added to honey as control. Honey and starch as well as honey and water were incubated for 24 hours at 37°C before being incorporated to nutrient agar. The same volume of starch was added to media without honey as control. The MIC for each batch of media was then determined. MAIN RESULTS The MIC for the three varieties of honey without starch was 11 %, 24 % and 29 %. When starch was added to the media containing honey the MIC obtained was 5 %, 19 % and 25 % respectively. The inhibitory action was shown neither in the media containing starch only nor in media with honey and water with the corresponding MIC. CONCLUSION As amylases originating from bees and pollen are present in honey, these split starch chains to randomly produce dextrin and maltose and probably increase the osmotic effect in the media by increasing the amount of sugars and consequently increase the antibacterial activity. Clinical trials using a mixture of honey and starch to treat infections could validate this finding. [ABSTRACT FROM AUTHOR]

Background: Diffuse large B-cell lymphoma (DLBCL) exhibits heterogeneous clinical features and a marked variable response to treatment. Patients and methods: We investigated the prognostic significance of the methylation status of DAPK, GSTP1, P14, P15, P16, P33, RB1, SHP1, CDH1, APC, BLU, VHL, TIMP3, and RASSF1A genes in 46 DLBCL specimens from Tunisian patients. Methylation status of each gene was correlated with clinicopathological parameters including the International Prognostic Index (IPI), the germinal center immunophenotype, and response to treatment and survival. Overall survival (OS) and disease-free survival (DFS) rates were calculated by the Kaplan–Meier method and differences were compared with the log-rank test. Results: Hypermethylation of SHP1 was associated with elevated lactate dehydrogenase level (P = 0.031). P16 and VHL were frequently hypermethylated in patients with high IPI scores (P = 0.006 and 0.004) and a performance status of two or more (P = 0.007 and 0.047). In addition, hypermethylation of P16 was significantly associated with advanced clinical stages and B symptoms (P = 0.041 and 0.012). Interestingly, hypermethylation of DAPK was significantly correlated with resistance to treatment (P = 0.023). With regard to survival rates, promoter hypermethylation of DAPK, P16, and VHL were significantly associated with shortened OS (P = 0.003, 0.001, and 0.017, respectively) and DFS (P = 0.006, 0.003, and 0.046, respectively). In multivariate analysis, hypermethylation of DAPK remains an independent prognostic factor in predicting shortened OS (P = 0.001) and DFS (P = 0.024), as well as the IPI and the germinal center status. Conclusions: This study demonstrates that DLBCLs with hypermethylated P16, VHL, DAPK, and SHP1 commonly show a biologically aggressive phenotype and worse prognosis. Interestingly, hypermethylation of DAPK was found to be an independent prognostic factor that may be used in conjunction with the conventional prognostic factors such as the IPI and the germinal center status. [ABSTRACT FROM AUTHOR]

BACKGROUND Sahara honey was compared with other varieties of Algerian honey for its effectiveness against Pseudomonas aerugenosa. MATERIAL AND METHODS Six varieties of honey from different regions in Algeria were used to determine their potency against Pseudomonas aerugenosa. Four varieties originated from northern Algeria and two from the Sahara. Two types of media were used: nutrient broth and King A agar. The media incorporation technique was used. For each variety the Minimum Inhibitory Concentration (MIC) was determined by finding the plate with the lowest concentration of honey on which the strain would not grow or the tube with the lowest concentration of honey without the development of a veil of colonies on its top. MAIN RESULTS On the King A agar the MIC of the four northern varieties ranged from 25 % to 31 % whereas the MIC of the two varieties of Sahara honey was 12 % and 15 %. On nutrient broth the MIC of the northern varieties ranged from 10 % to 21 % whereas the MIC of the two varieties of Sahara honey was 9%. CONCLUSION The botanic flora of the Sahara is known in Algeria for its medicinal use. The higher potency of the Sahara honey is most probably due to its plant-derived antibacterial substances. Further studies may elucidate the nature of these substances. [ABSTRACT FROM AUTHOR]

Clostridioides difficile causes a wide range of intestinal diseases through the action of two main cytotoxins, TcdA and TcdB. Ingested spores germinate in the intestine establishing a population of cells that produce toxins and spores. The pathogenicity locus, PaLoc, comprises several genes, including those coding for TcdA/B, for the holin-like TcdE protein, and for TcdR, an auto-regulatory RNA polymerase sigma factor essential for tcdA/B and tcdE expression. Here we show that tcdR, tcdA, tcdB and tcdE are expressed in a fraction of the sporulating cells, in either the whole sporangium or in the forespore. The whole sporangium pattern is due to protracted expression initiated in vegetative cells by σ D , which primes the TcdR auto-regulatory loop. In contrast, the forespore-specific regulatory proteins σ G and SpoVT control TcdR production and tcdA/tcdB and tcdE expression in this cell. We detected TcdA at the spore surface, and we show that wild type and ΔtcdA or ΔtcdB spores but not ΔtcdR or ΔtcdA/ΔtcdB spores are cytopathic against HT29 and Vero cells, indicating that spores may serve as toxin-delivery vehicles. Since the addition of TcdA and TcdB enhance binding of spores to epithelial cells, this effect may occur independently of toxin production by vegetative cells., (© 2024. The Author(s).)

Solar Photovoltaic (PV) systems are increasingly vital for enhancing energy security worldwide. However, their efficiency and power output can be significantly reduced by hotspots and snail trails, predominantly caused by cracks in PV modules. This article introduces a novel methodology for the automatic segmentation and analysis of such anomalies, utilizing unsupervised sensing algorithms coupled with 3D Augmented Reality (AR) for enhanced visualization. The methodology outperforms existing segmentation techniques, including Weka and the Meta Segment Anything Model (SAM), as demonstrated through computer simulations. These simulations were conducted using the Cali-Thermal Solar Panels and Solar Panel Infrared Image Datasets, with evaluation metrics such as the Jaccard Index, Dice Coefficient, Precision, and Recall, achieving scores of 0.76, 0.82, 0.90, 0.99, and 0.76, respectively. By integrating drone technology, the proposed approach aims to revolutionize PV maintenance by facilitating real-time, automated solar panel detection. This advancement promises substantial cost reductions, heightened energy production, and improved performance of solar PV installations. Furthermore, the innovative integration of unsupervised sensing algorithms with 3D AR visualization opens new avenues for future research and development in the field of solar PV maintenance., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Author(s).)

Explainable machine learning is increasingly used in drug discovery to help rationalize compound property predictions. Feature attribution techniques are popular choices to identify which molecular substructures are responsible for a predicted property change. However, established molecular feature attribution methods have so far displayed low performance for popular deep learning algorithms such as graph neural networks (GNNs), especially when compared with simpler modeling alternatives such as random forests coupled with atom masking. To mitigate this problem, a modification of the regression objective for GNNs is proposed to specifically account for common core structures between pairs of molecules. The presented approach shows higher accuracy on a recently-proposed explainability benchmark. This methodology has the potential to assist with model explainability in drug discovery pipelines, particularly in lead optimization efforts where specific chemical series are investigated., (© 2023. The Author(s).)

B cells play a significant role in established Rheumatoid Arthritis (RA). However, it is unclear to what extent differentiated B cells are present in joint tissue already at the onset of disease. Here, we studied synovial biopsies (n = 8) captured from untreated patients at time of diagnosis. 3414 index-sorted B cells underwent RNA sequencing and paired tissue pieces were subjected to spatial transcriptomics (n = 4). We performed extensive bioinformatics analyses to dissect the local B cell composition. Select plasma cell immunoglobulin sequences were expressed as monoclonal antibodies and tested by ELISA. Memory and plasma cells were found irrespective of autoantibody status of the patients. Double negative memory B cells were prominent, but did not display a distinct transcriptional profile. The tissue architecture implicate both local B cell maturation via T cell help and plasma cell survival niches with a strong CXCL12-CXCR4 axis. The immunoglobulin sequence analyses revealed clonality between the memory B and plasma cell pools further supporting local maturation. One of the plasma cell-derived antibodies displayed citrulline autoreactivity, demonstrating local autoreactive plasma cell differentiation in joint biopsies captured from untreated early RA. Hence, plasma cell niches are not a consequence of chronic inflammation, but are already present at the time of diagnosis., (© 2022. The Author(s).)

With the Coronavirus disease 2019 (COVID-19) spread, causing a world pandemic, and recently, the virus new variants continue to appear, making the situation more challenging and threatening, the visual assessment and quantification by expert radiologists have become costly and error-prone. Hence, there is a need to propose a model to predict the COVID-19 cases at the earliest possible to control the disease spread. In order to assist the medical professionals and reduce workload and the time the COVID-19 diagnosis cycle takes, this paper proposes a novel neural network architecture termed as O-Net to automatically segment chest Computerised Tomography Ct-scans infected by COVID-19 with optimised computing power and memory occupation. The O-Net consists of two convolutional autoencoders with an upsampling channel and a downsampling channel. Experimental tests show our proposal's effectiveness and potential, with a dice score of 0.86, pixel accuracy, precision, specificity of 0.99, 0.99, 0.98, respectively. Performance on the external dataset illustrates generalisation and scalability capabilities of the O-Net model to Ct-scan obtained from different scanners with different sizes. The second objective of this work is to introduce our virtual reality platform, COVIR, that visualises and manipulates 3D reconstructed lungs and segmented infected lesions caused by COVID-19. COVIR platform acts as a reading and visualisation support for medical practitioners to diagnose COVID-19 lung infection. The COVIR platform could be used for medical education professional practice and training. It was tested by Thirteen participants (medical staff, researchers, and collaborators), they conclude that the 3D VR visualisation of segmented Ct-Scan provides an aid diagnosis tool for better interpretation., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 Elsevier Ltd. All rights reserved.)

Based on the epidemiological link between periodontitis and rheumatoid arthritis (RA), and the unique feature of the periodontal bacterium Porphyromonas gingivalis to citrullinate proteins, it has been suggested that production of anti-citrullinated protein antibodies (ACPA), which are present in a majority of RA patients, may be triggered in the gum mucosa. To address this hypothesis, we investigated the antibody response to a citrullinated P. gingivalis peptide in relation to the autoimmune ACPA response in early RA, and examined citrulline-reactivity in monoclonal antibodies derived from human gingival B cells. Antibodies to a citrullinated peptide derived from P. gingivalis (denoted CPP3) and human citrullinated peptides were analyzed by multiplex array in 2,807 RA patients and 372 controls; associations with RA risk factors and clinical features were examined. B cells from inflamed gingival tissue were single-cell sorted, and immunoglobulin (Ig) genes were amplified, sequenced, cloned and expressed (n=63) as recombinant monoclonal antibodies, and assayed for citrulline-reactivities by enzyme-linked immunosorbent assay. Additionally, affinity-purified polyclonal anti-cyclic-citrullinated peptide (CCP2) IgG, and monoclonal antibodies derived from RA blood and synovial fluid B cells (n=175), were screened for CPP3-reactivity. Elevated anti-CPP3 antibody levels were detected in RA (11%), mainly CCP2+ RA, compared to controls (2%), p<0.0001, with a significant association to HLA-DRB1 shared epitope alleles, smoking and baseline pain, but with low correlation to autoimmune ACPA fine-specificities. Monoclonal antibodies derived from gingival B cells showed cross-reactivity between P. gingivalis CPP3 and human citrullinated peptides, and a CPP3+/CCP2+ clone, derived from an RA blood memory B cell, was identified. Our data support the possibility that immunity to P. gingivalis derived citrullinated antigens, triggered in the inflamed gum mucosa, may contribute to the presence of ACPA in RA patients, through mechanisms of molecular mimicry., Competing Interests: Karolinska Institutet has been a partner with Thermo Fisher Scientific within the Innovative Medicines Initiative BTCure, a public–private partnership between the EU and the European Federation of Pharmaceutical Industries (www.BTcure.eu). Thermo Fisher Scientific has contributed to this consortium with in-kind contributions for the development of the multiplex assay used in the study. LM-A is employed by Thermo Fischer Scientific. JR is member of the Thermo Fisher Scientific advisory board. KL is co-inventor of patent: US12/524,465, describing the diagnostic use of the CEP-1 epitope. RH is a co-inventor of patent: US Patent 7 148 020, protecting the use of the CitC1 peptide. GJ was employed by Praktikertjänst AB. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Sherina, de Vries, Kharlamova, Sippl, Jiang, Brynedal, Kindstedt, Hansson, Mathsson-Alm, Israelsson, Stålesen, Saevarsdottir, Holmdahl, Hensvold, Johannsen, Eriksson, Sallusto, Catrina, Rönnelid, Grönwall, Yucel-Lindberg, Alfredsson, Klareskog, Piccoli, Malmström, Amara and Lundberg.)

Objective: Anti-citrullinated protein antibodies (ACPAs) are a hallmark of seropositive rheumatoid arthritis (RA). Yet, the precise disease-relevant autoantigens that are targeted by ACPAs remains a matter of debate. This study utilized patient-derived monoclonal ACPAs, rather than serum autoantibody analysis, to characterize the multireactivity to different protein modifications and to reveal autoantibody subsets in patients with RA., Methods: Twelve human monoclonal ACPAs (positive by the second-generation cyclic citrullinated peptide test) were generated from 6 RA patients, and a head-to-head comparison of their reactivities was performed. For profiling, we used a complementary DNA-based protein array (Engine GmbH) and 3 peptide-screening platforms with RA autoantigens (Thermo Fisher Scientific), citrullinated and carbamylated peptides (NimbleGen/Roche), or histone-derived peptides with different posttranslational modifications (JPT Histone Code), covering >207,000 peptides (>7,800 gene products)., Results: The fine-specificity profiles of the investigated ACPAs varied, but all of the monoclonal ACPAs displayed multireactivity to a large number of citrullinated peptides/proteins, each characterized by specific binding properties. ACPA subsets could be defined by clone-distinct consensus binding motifs (e.g., Cit-Gly, Gly-Cit, or Arg-Cit-Asp), with the most common ACPA recognition being that of a Gly in the +1 flanking position, but with additional amino acid preferences. For ACPA protein recognition, we observed a preference for citrullinated RNA-binding proteins with high Arg/Gly content. Six of the 12 ACPA clones also bound acetylated lysine (KAc) or homocitrulline peptide motifs, displaying a similar affinity or higher apparent affinity than that for citrullinated peptides., Conclusion: ACPAs and anti-modified protein autoantibodies represent overlapping facets of RA autoimmunity and bind to a wide variety of modified proteins, extending well beyond the historically recognized set of RA autoantigens. So far, KAc reactivity has been detected only in the context of anti-carbamylated and anti-citrullinated peptide autoantibody responses, postulating the existence of hierarchies of autoreactivity in RA. Future investigations of ACPA fine specificities and functionality should take into consideration the presence of consensus Cit/Carb/KAc motifs and the multireactivity of these autoantibodies in patients with RA., (© 2020 The Authors. Arthritis & Rheumatology published by Wiley Periodicals LLC on behalf of American College of Rheumatology.)

We describe here a detailed, refined protocol for the generation of citrulline-specific monoclonal antibodies from single human B cells from rheumatoid arthritis (RA) patients. This protocol provides a detailed guide of the procedure starting from single B cells of your choice and followed by amplification of the variable region of immunoglobulin genes by RT-PCR, subsequent immunoglobulin gene cloning, recombinant IgG1 monoclonal antibody (mAb) production and quality controls. The produced mAbs can be used for further studies including reactivity towards candidate antigens and functionality both in vitro and in vivo . This protocol can be used to generate antigen-specific mAbs from B cells derived from different tissues and compartments, including peripheral blood, synovial fluid, digested biopsies, bone marrow aspirations, and bronchoalveolar lavage fluid. Notably, although examples are given on how to identify citrulline-specific autoantibodies the general methods can also be applied to other reactivities., Competing Interests: Competing interestsThe authors have no conflict of interest., (Copyright © 2019 The Authors; exclusive licensee Bio-protocol LLC.)

Background: Systemic lupus erythematosus (SLE) is a systemic autoimmune disease, which exhibits multiple B cell abnormalities including expanded populations of memory B cells and elevated levels of autoantibodies. Belimumab is a monoclonal antibody targeting the B cell cytokine BAFF (a.k.a. BLyS), approved for the treatment of SLE., Methods: In this prospective cohort study, B cells from peripheral blood of 23 SLE patients initiating belimumab treatment and followed longitudinally for up to three years, were assessed using mass cytometry., Findings: B cells decreased during the study period, with a rapid decrease of both naïve and CD11c + CD21 - B cells at the first follow-up visit, followed by a continuous reduction at subsequent follow-ups. In contrast, plasma cells and switched memory B cells remained stable throughout the study. The observed immunological changes correlated with early, but not late, clinical improvements. Moreover, high baseline B cell counts were predictive of failure to attain low disease activity. In summary, our data unveiled both rapid and gradual later therapy-associated alterations of both known and unforeseen B cell phenotypes., Interpretation: Our results suggest that evaluation of B cell counts might prove useful prior to initiation of belimumab treatment and that early treatment evaluation and discontinuation might underestimate delayed clinical improvements resultant of late B cell changes., (Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.)

Objective: Anti-citrullinated protein antibodies (ACPAs) have proven highly useful as biomarkers for rheumatoid arthritis (RA). However, composition and functionality of the associated autoreactive B cell repertoire have not been directly assessed. We aimed to selectively investigate citrullinated autoantigen-specific B cell receptors (BCRs) involved in RA and initiate studies on their pathogenicity., Methods: Blood samples were obtained from patients in a University of Minnesota cohort with ACPA-positive RA (n = 89). Tetramer sets bearing citrullinated filaggrin peptide cfc1 or citrullinated α-enolase peptide were constructed to specifically capture autoreactive B cells from the unaltered, polyclonal repertoire in RA patients. Citrullinated peptide tetramer-bound B cells were subjected to flow cytometric cell sorting and single-cell IGH, IGK, and IGL gene sequencing for B cell lineage determinations. BCR gene sequences were also expressed as recombinant monoclonal antibodies (mAb) for direct evaluation of citrullinated autoantigen binding and effector functionality., Results: Using citrullinated peptide tetramer enrichment to investigate single autoreactive blood B cells, we identified biased V-region gene usage and conserved junction arrangements in BCRs from RA patients. Parsimonious clustering of related immunoglobulin gene nucleotide sequences revealed clonal expansions of rare individual B cell clades, in parallel with divergent sequence mutations. Correspondingly, recombinant mAb generated from such BCR lineages demonstrated citrulline-dependent cross-reactivity extending beyond the citrullinated peptides used for B cell capture. A pair of citrullinated autoantigen-specific mAb with cross-reactive binding profiles also promoted arthritis in mice., Conclusion: Our findings suggest that broad ACPA specificities in RA arise from a restricted repertoire of evolving citrulline-multispecific B cell clades with pathogenic potential., (© 2018, American College of Rheumatology.)

This manuscript is a companion paper to Amara et al. [1]. Data shown here include detailed clinical characteristics from anonymized patients, the Ig subclass data generated from B cells sorted from four individual patients, tables detailing variable gene region sequences from sorted cells linked to the patient information and the sequence yields from individual patients. Furthermore a URL link to the RNAseq datasets submitted to GEO is included.

Immunglobulin G (IgG) sialylation represents a key checkpoint that determines the engagement of pro- or anti-inflammatory Fcγ receptors (FcγR) and the direction of the immune response. Whether IgG sialylation influences osteoclast differentiation and subsequently bone architecture has not been determined yet, but may represent an important link between immune activation and bone loss. Here we demonstrate that desialylated, but not sialylated, immune complexes enhance osteoclastogenesis in vitro and in vivo. Furthermore, we find that the Fc sialylation state of random IgG and specific IgG autoantibodies determines bone architecture in patients with rheumatoid arthritis. In accordance with these findings, mice treated with the sialic acid precursor N-acetylmannosamine (ManNAc), which results in increased IgG sialylation, are less susceptible to inflammatory bone loss. Taken together, our findings provide a novel mechanism by which immune responses influence the human skeleton and an innovative treatment approach to inhibit immune-mediated bone loss.

Antibodies targeting citrullinated proteins (ACPAs [anticitrullinated protein antibodies]) are commonly found in patients with rheumatoid arthritis (RA), strongly associate with distinct HLA-DR alleles, and predict a more aggressive disease course as compared with seronegative patients. Still, many features of these antibodies, including their site of production and the extent of MHC class II-driven T cell help, remain unclarified. To address these questions, we have used a single B cell-based cloning technology to isolate and express immunoglobulin (Ig) genes from joint-derived B cells of active RA patients. We found ∼25% of synovial IgG-expressing B cells to be specific for citrullinated autoantigens in the investigated ACPA(+) RA patients, whereas such antibodies were not found in ACPA(-) patients. The citrulline-reactive monoclonal antibodies did not react with the unmodified arginine peptides, yet several reacted with more than one citrullinated antigen. A role for active antigen selection of the citrulline-reactive synovial B cells was supported by the strong bias toward amino acid replacement mutations in ACPA(+) antibodies and by their loss of reactivity to citrullinated autoantigens when somatic mutations were reverted to the corresponding germline sequences.

Objective: To evaluate the clinical and radiological outcome of anterior vascularized bone graft in the treatment of primitive nonunion of the scaphoid., Methods: This is a retrospective study of 26 scaphoid nonunion cases treated by this technique between 2004 and 2009. The mean age was 38 years. Nonunion was of types IIA and IIB according to the Alnot's classification and only one case showed a proximal pole necrosis (type IV). The fixation was ensured by K-wire. The mean immobilization period was 9 weeks., Results: At mean 19 months follow-up, the bone union rate was 88.5%. Failure was noted in three cases. No significant complications secondary to this technique were observed. The mobility in extension and flexion had an average recovery of 18 degree Nineteen patients (73%) were free of pain, and the others had occasional pain., Conclusions: It is a meticulous surgical technique that provides better union rates than those of conventional scaphoid graft. This technique is first adopted in cases of failure of conventional grafts in the treatment of scaphoid nonunion but the encouraging results suggest expanding indications to primitive nonunion.

The aim of this study was to evaluate the prevalence of broad range of anogenital HPVs in a series of 123 Tunisian breast carcinoma cases. PCR assays were performed to amplify regions within the L1, E1, E6 and E7 open reading frames of a broad range of anogenital HPVs and specific types HPV16, 18, 31 and 33. In addition, we performed an in situ hybridization analysis using HPV biotinylated DNA probes for the detection of broad spectrum of anogenital HPV types, high-risk HPV types (16 and 18), intermediate-risk HPV types (31 and 33) and low-risk HPV types (6 and 11). None of the 123 breast carcinoma samples showed PCR amplification of HPV DNA using the broad spectrum consensus primer-pairs E1-350L/E1-547R and GP5+/GP6+ primers. Furthermore, neither high risk nor low-risk HPV types were detected in any of these cases. Moreover, using in situ hybridization for the detection of HPVs, we failed to detect a positive signal in neoplastic cells in any case. Our results suggest that anogenital papillomaviruses are unlikely to play a role in the development of breast carcinomas in Tunisian patients., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Diffuse large B-cell lymphomas (DLBCL) are the most common type of aggressive lymphomas, with considerable heterogeneity in clinical presentation, molecular characteristics, and outcome. Previous studies have showed significant correlations between DNA methyltransferase (DNMT) overexpression and unfavorable prognosis in human cancers. Therefore, we investigated in this study the biological and prognostic significance of DNMT1, DNMT3a, and DNMT3b protein expression in DLBCL. DNA methyltransferase (DNMT) expression was analyzed by immunohistochemistry in 81 DLBCL cases and correlated with clinicopathological parameters. Kaplan-Meier curves were used to estimate survival rates, and the Cox proportional hazard regression model was used to evaluate the prognostic impact of DNMT expression. Our results showed that overexpression of DNMT1, DNMT3a, and DNMT3b were detected in 48%, 13%, and 45% of investigated cases, respectively. DNA methyltransferase 1 (DNMT1) and DNMT3b overexpression was significantly correlated with advanced clinical stages (P = 0.028 and P = 0.016, respectively). Moreover, concomitant expression of DNMT1 and DNMT3b was significantly correlated with resistance to treatment (P = 0.015). With regard to survival rates, although data was available only for 40 patients, DNMT3b overexpression was significantly correlated with shorter overall survival (P = 0.006) and progression-free survival (P = 0.016). Interestingly, multivariate analysis demonstrated that DNMT3b overexpression was an independent prognostic factor for predicting shortened overall survival (P = 0.004) and progression-free survival (P = 0.024). In conclusion, DNMT3b overexpression was identified as an independent prognostic factor for predicting shortened survival of patients with DLBCL and could be, therefore, useful in identifying patients who would benefit from aggressive therapy.

Previously we have reported the presence of simian virus 40 DNA in 56% of diffuse large B-cell lymphomas in Tunisia. Here, we investigated the relationship between the status of simian virus 40 and t(14;18) translocation, germinal center status, and P53 and BCL2 expression to assess the clinical and biological relevance of simian virus 40 presence in diffuse large B-cell lymphomas. Therefore, we evaluated by immunohistochemistry the expression patterns of CD10, BCL6, MUM1, BCL2, and P53 in 86 diffuse large B-cell lymphomas (48 simian virus 40-positive and 38 simian virus 40-negative cases). The t(14;18) translocation was investigated by polymerase chain reaction. Immunostaining patterns for CD10, BCL6, and MUM1 were used to subclassify diffuse large B-cell lymphoma cases as germinal center or non-germinal center phenotypes. Germinal center phenotype, t(14;18), P53, and BCL2 expression were found in 71, 30, 55, and 65% of cases, respectively. Interestingly, germinal center phenotype, t(14;18), and P53 accumulation were found to be more frequent in simian virus 40-positive cases than in simian virus 40-negative ones (81, 44, 69 vs 58, 13, 37%; P=0.018, 0.002, and 0.003, respectively). However, there were no correlations between the presence of simian virus 40 and the expression of CD10, BCL6, MUM1 and BCL2, patient's age and gender, clinical stage, or the International Prognosis Index. Multivariate logistic regression analyses revealed that the germinal center phenotype, P53 accumulation, and t(14;18) were independent factors for simian virus 40 association (P=0.029, 0.006, and 0.014, respectively). There were no significant differences in overall survival regarding P53, BCL2, or t(14;18) status. However, patients with germinal center phenotype or low International Prognosis Index scores displayed a significantly better survival than those with non-germinal center phenotype or high International Prognosis Index scores (P=0.003 and 0.0001, respectively). These two prognosis factors remain independent in multivariate analyses (P=0.001 and <0.0001, respectively). Interestingly, among patients with germinal center phenotype, simian virus 40-positive subgroup displayed a significantly shorter survival than simian virus 40-negative subgroup (P=0.034). In summary, these findings support a role of simian virus 40 in the pathogenesis of diffuse large B-cell lymphomas. On other hand, they suggest that a significant proportion of diffuse large B-cell lymphoma cases with germinal center phenotype may result from early transformation by simian virus 40, mainly those harboring the t(14;18). Modern Pathology (2008) 21, 282-296; doi:10.1038/modpathol.3800993; published online 28 December 2007.

The role of amylase present in honey in enhancing its antibacterial activity was evaluated in the presence and absence of starch. Two strains of pathogenic bacteria have been used: Staphylococcus aureus and Escherichia coli. For S. aureus, the minimum inhibitory concentration (MIC) for the three varieties of honey tested without starch was 11%, 24%, and 29% (vol/vol), respectively. When starch was added with honey to the media the MIC obtained was 5%, 19%, and 25% (vol/vol), respectively. For E. coli, the MIC for the three varieties without starch was 23%, 28%, and 25% (vol/vol), respectively. When starch was added with honey to media, the MIC was 19%, 26%, and 23% (vol/vol), respectively. It is speculated that the amylase present in honey hydrolyzed the starch chains to randomly produce dextrin and maltose and that this increased the osmotic effect of the media, which consequently increased the antibacterial activity.