Silver(I) complexes with voriconazole as promising anti-Candida agents

Recognizing that metal ions play an important role in modifying the pharmacological properties of known organic-based drugs, the present manuscript addresses the complexation of the antifungal agent voriconazole (vcz) with the biologically relevant silver(I) ion as a strategy for the development of new antimycotics. The synthesized silver(I) complexes with vcz were characterized by mass spectrometry, IR, UV-Vis and NMR spectroscopy and single-crystal X-ray diffraction analysis. The crystallographic results showed that complexes {[Ag(vcz)(H2O)]CH3SO3}n (1), {[Ag(vcz)2]BF4}n (2) and {[Ag(vcz)2]PF6}n (3) have polymeric structures in the solid state, in which silver(I) ions have a distorted tetrahedral geometry. On the other hand, DFT calculations revealed that the investigated silver(I) complexes 1-3 in DMSO exist as linear [Ag(vcz-N2)(vcz-N19)]+ (1a), [Ag(vcz-N2)(vcz-N4)]+ (2a) and [Ag(vcz-N4)2]+ (3a) species, respectively. The evaluated complexes showed an enhanced anti-Candida activity compared to the parent drug with minimal inhibitory concentration (MIC) values in the range of 0.02-1.05 μM. In comparison with vcz, the corresponding silver(I) complexes showed better activity in prevention hyphae and biofilm formation of C. albicans, indicating that they could be considered as promising agents against Candida that significantly inhibit its virulence. Also, these complexes are much better inhibitors of ergosterol synthesis in the cell membrane of C. albicans at the concentration of 0.5 × MIC. This is also confirmed by a molecular docking, which revealed that complexes 1a - 3a showed better inhibitory activity than vcz against the sterol 14α-demethylase enzyme cytochrome P450 (CYP51B), which plays a crucial role in the formation of ergosterol.

Silver(I) complexes containing antifungal azoles: significant improvement of the anti-Candida potential of the azole drug after its coordination to the silver(I) ion

Inspired by the emergence of resistance to currently available antifungal therapy and by the great potential of metal complexes for the treatment of various diseases, we synthesized three new silver(I) complexes containing clinically used antifungal azoles as ligands, [Ag(ecz)2]SbF6 (1, ecz is econazole), {[Ag(vcz)2]SbF6}n (2, vcz is voriconazole), and [Ag(ctz)2]SbF6 (3, ctz is clotrimazole), and investigated their antimicrobial properties. The synthesized complexes were characterized by mass spectrometry, IR, UV-vis and 1H NMR spectroscopy, cyclic voltammetry, and single-crystal X-ray diffraction analysis. In the mononuclear complexes 1 and 3 with ecz and ctz, respectively, the silver(I) ion has the expected linear geometry, in which the azoles are monodentately coordinated to this metal center through the N3 imidazole nitrogen atom. In contrast, the vcz-containing complex 2 has a polymeric structure in the solid state in which the silver(I) ions are coordinated by four nitrogen atoms in a distorted tetrahedral geometry. DFT calculations were done to predict the most favorable structures of the studied complexes in DMSO solution. All the studied silver(I) complexes have shown excellent antifungal and good to moderate antibacterial activities with minimal inhibitory concentration (MIC) values in the ranges of 0.01-27.1 and 2.61-47.9 μM on the selected panel of fungi and bacteria, respectively. Importantly, the complexes 1-3 have exhibited a significantly improved antifungal activity compared to the free azoles, with the most pronounced effect observed in the case of complex 2 compared to the parent vcz against Candida glabrata with an increase of activity by five orders of magnitude. Moreover, the silver(I)-azole complexes 2 and 3 significantly inhibited the formation of C. albicans hyphae and biofilms at the subinhibitory concentration of 50% MIC. To investigate the impact of the complex 3 more thoroughly on Candida pathogenesis, its effect on the adherence of C. albicans to A549 cells (human adenocarcinoma alveolar basal epithelial cells), as an initial step of the invasion of host cells, was studied.

Upcycling of food waste streams to valuable biopigments pyocyanin and 1-hydroxyphenazine

Phenazines, including pyocyanin (PYO) and 1-hydroxyphenazine (1-HP) are extracellular secondary metabolites and multifunctional pigments of Pseudomonas aeruginosa responsible for its blue-green color. These versatile molecules are electrochemically active, involved in significant biological activities giving fitness to the host, but also recognized as antimicrobial and anticancer agents. Their wider application is still limited partly due to the cost of carbon substrate for production, which can be solved by the utilization of carbon from food waste within the biorefinery concept. In this study, a variety of food waste streams (banana peel, potato peel, potato washing, stale bread, yoghurt, processed meat, boiled eggs and mixed canteen waste) was used as sole nutrient source in submerged cultures of P. aeruginosa BK25H. Stale bread was identified as the most suitable substrate to support phenazine biopigments production and bacterial growth. This was further increased in 5-liter fermenter when on average 5.2 mg L-1 of PYO and 4.4 mg L-1 of 1-HP were purified after 24 h batch cultivations from the fermentation medium consisting of homogenized stale bread in tap water. Purified biopigments showed moderate antimicrobial activity, and showed different toxicity profiles, with PYO not being toxic against Caenorhabditis elegans, a free-living soil nematode up to 300 µg mL-1 and 1-HP showing lethal effects at 75 µg mL-1. Therefore, stale bread waste stream with minimal pretreatment should be considered as suitable biorefinery feedstock, as it can support the production of valuable biopigments such as phenazines.

Pediatric acute myeloid leukemia: Insight into genetic landscape and novel targeted approaches

Acute myeloid leukemia (AML) is a very heterogeneous hematological malignancy that accounts for approximately 20% of all pediatric leukemia cases. The outcome of pediatric AML has improved over the last decades, with overall survival rates reaching up to 70%. Still, AML is among the leading types of pediatric cancers by its high mortality rate. Modulation of standard therapy, like chemotherapy intensification, hematopoietic stem cell transplantation and optimized supportive care, could only get this far, but for the significant improvement of the outcome in pediatric AML, development of novel targeted therapy approaches is necessary. In recent years the advances in genomic techniques have greatly expanded our knowledge of the AML biology, revealing molecular landscape and complexity of the disease, which in turn have led to the identification of novel therapeutic targets. This review provides a brief overview of the genetic landscape of pediatric AML, and how it's used for precise molecular characterization and risk stratification of the patients, and also for the development of effective targeted therapy. Furthermore, this review presents recent advances in molecular targeted therapy and immunotherapy with an emphasis on the therapeutic approaches with significant clinical benefits for pediatric AML.

Perception and management of cancer predisposition in pediatric cancer centers: A European-wide questionnaire-based survey

The European Union-funded COST Action (LEukaemia GENe Discovery by data sharing, mining, and collaboration) LEGEND was an international and multidisciplinary collaboration between clinicians and researchers that covered a range of aspects of genetic predisposition in childhood leukemia. Within this framework, we explored the perception and handling of genetic predisposition in the daily practice of European treatment centers. Herein, we present the results of our questionnaire-based survey. We found that the overall awareness is quite high, and respondents remarked that identification and treatment of the most common predisposition syndromes were present. Nevertheless, high demand for continuous education and routinely updated resources remains.

Advancing PHBV Biomedical Potential with the Incorporation of Bacterial Biopigment Prodigiosin

The quest for sustainable biomaterials with excellent biocompatibility and tailorable properties has put polyhydroxyalkanoates (PHAs) into the research spotlight. However, high production costs and the lack of bioactivity limit their market penetration. To address this, poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) was combined with a bacterial pigment with strong anticancer activity, prodigiosin (PG), to obtain functionally enhanced PHBV-based biomaterials. The samples were produced in the form of films 115.6-118.8 µm in thickness using the solvent casting method. The effects of PG incorporation on the physical properties (morphology, biopolymer crystallinity and thermal stability) and functionality of the obtained biomaterials were investigated. PG has acted as a nucleating agent, in turn affecting the degree of crystallinity, thermal stability and morphology of the films. All samples with PG had a more organized internal structure and higher melting and degradation temperatures. The calculated degree of crystallinity of the PHBV copolymer was 53%, while the PG1, PG3 and PG3 films had values of 64.0%, 63.9% and 69.2%, respectively. Cytotoxicity studies have shown the excellent anticancer activity of films against HCT116 (colon cancer) cells, thus advancing PHBV biomedical application potential.

Pediatric Precursor B-Cell Lymphoblastic Malignancies: From Extramedullary to Medullary Involvement

B-cell lymphoblastic lymphoma (BCP-LBL) and B-cell acute lymphoblastic leukemia (BCP-ALL) are the malignant counterparts of immature B-cells. BCP-ALL is the most common hematological malignancy in childhood, while BCP-LBL accounts for only 1% of all hematological malignancies in children. Therefore, BCP-ALL has been well studied and treatment protocols have changed over the last decades, whereas treatment for BCP-LBL has stayed roughly the same. Clinical characteristics of 364 pediatric patients with precursor B-cell malignancies were studied, consisting of BCP-LBL (n = 210) and BCP-ALL (n = 154) patients. Our results indicate that based on the clinical presentation of disease, B-cell malignancies probably represent a spectrum ranging from complete isolated medullary disease to apparent complete extramedullary disease. Hepatosplenomegaly and peripheral blood involvement are the most important discriminators, as both seen in 80% and 95% of the BCP-ALL patients and in 2% of the BCP-LBL patients, respectively. In addition, we show that the overall survival rates in this cohort differ significantly between BCP-LBL and BCP-ALL patients aged 1−18 years (p = 0.0080), and that the outcome for infants (0−1 years) with BCP-LBL is significantly decreased compared to BCP-LBL patients of all other pediatric ages (p < 0.0001).

Primary post-transplant lymphoproliferative disorder of the central nervous system: characteristics, management and outcome in 25 paediatric patients

Primary central nervous system (CNS) post-transplant lymphoproliferative disorder (PTLD) in childhood is rare. Twenty-five patients were retrieved from nine European Intergroup for Childhood Non-Hodgkin's Lymphoma and/or international Berlin-Frankfurt-Münster Study Group members. Types of allografts included kidney (n = 11), liver (n = 4), heart (n = 5), bowel (n = 1) and haematopoietic stem cells (n = 4). Eighteen were male, 16 ≥ 10 years old, 21 had monomorphic disease and 24 solid intracranial tumour masses. Four-year event-free and overall survival rates were 50% ± 10% and 74% ± 9% respectively. This report represents the largest paediatric series of CNS PTLD reported to date, showing favourable survival odds following systemic and intrathecal chemotherapy and rituximab administration.

Flash survey on severe acute respiratory syndrome coronavirus-2 infections in paediatric patients on anticancer treatment

INTRODUCTION

Since the beginning of COVID-19 pandemic, it is known that the severe course of the disease occurs mostly among the elderly, whereas it is rare among children and young adults. Comorbidities, in particular, diabetes and hypertension, clearly associated with age, besides obesity and smoke, are strongly associated with the need for intensive treatment and a dismal outcome. A weaker immunity of the elderly has been proposed as a possible explanation of this uneven age distribution. Thus, there is concern that children treated for cancer may allso be at risk for an unfavourable course of infection. Along the same line, anecdotal information from Wuhan, China, mentioned a severe course of COVID-19 in a child treated for leukaemia.

AIM AND METHODS

We made a flash survey on COVID-19 incidence and severity among children on anticancer treatment. Respondents were asked by email to fill in a short Web-based survey.

RESULTS

We received reports from 25 countries, where approximately 10,000 patients at risk are followed up. At the time of the survey, more than 200 of these children were tested, nine of whom were positive for COVID-19. Eight of the nine cases had asymptomatic to mild disease, and one was just diagnosed with COVID-19. We also discuss preventive measures that are in place or should be taken and treatment options in immunocompromised children with COVID-19.

CONCLUSION

Thus, even children receiving anticancer chemotherapy may have a mild or asymptomatic course of COVID-19. While we should not underestimate the risk of developing a more severe course of COVID-19 than that observed here, the intensity of preventive measures should not cause delays or obstructions in oncological treatment.

Flash survey on severe acute respiratory syndrome coronavirus-2 infections in paediatric patients on anticancer treatment

Introduction

Since the beginning of COVID-19 pandemic, it is known that the severe course of the disease occurs mostly among the elderly, whereas it is rare among children and young adults. Comorbidities, in particular, diabetes and hypertension, clearly associated with age, besides obesity and smoke, are strongly associated with the need for intensive treatment and a dismal outcome. A weaker immunity of the elderly has been proposed as a possible explanation of this uneven age distribution. Thus, there is concern that children treated for cancer may allso be at risk for an unfavourable course of infection. Along the same line, anecdotal information from Wuhan, China, mentioned a severe course of COVID-19 in a child treated for leukaemia.

Aim and methods

We made a flash survey on COVID-19 incidence and severity among children on anticancer treatment. Respondents were asked by email to fill in a short Web-based survey.

Results

We received reports from 25 countries, where approximately 10,000 patients at risk are followed up. At the time of the survey, more than 200 of these children were tested, nine of whom were positive for COVID-19. Eight of the nine cases had asymptomatic to mild disease, and one was just diagnosed with COVID-19. We also discuss preventive measures that are in place or should be taken and treatment options in immunocompromised children with COVID-19.

Conclusion

Thus, even children receiving anticancer chemotherapy may have a mild or asymptomatic course of COVID-19. While we should not underestimate the risk of developing a more severe course of COVID-19 than that observed here, the intensity of preventive measures should not cause delays or obstructions in oncological treatment.

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Flash survey was used to get data on COVID-19 incidence and severity.

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Paediatric haematology/oncology departments of 25 countries responded.

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COVID-19 may have a mild course in these immunocompromised children.

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Precautions should be taken to prevent any infections including COVID-19.

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Malignancy is a primary danger; preventive measures should not hinder its treatment.

Aromatic Guanylhydrazones for the Control of Heme-Induced Antibody Polyreactivity

In a healthy immune repertoire, there exists a fraction of polyreactive antibodies that can bind to a variety of unrelated self- and foreign antigens. Apart from naturally polyreactive antibodies, in every healthy individual, there is a fraction of antibody that can gain polyreactivity upon exposure to porphyrin cofactor heme. Molecular mechanisms and biological significance of the appearance of cryptic polyreactivity are not well understood. It is believed that heme acts as an interfacial cofactor between the antibody and the newly recognized antigens. To further test this claim and gain insight into the types of interactions involved in heme binding, we herein investigated the influence of a group of aromatic guanylhydrazone molecules on the heme-induced antibody polyreactivity. From the analysis of SAR and the results of UV-vis absorbance spectroscopy, it was concluded that the most probable mechanism by which the studied molecules inhibit heme-mediated polyreactivity of the antibody is the direct binding to heme, thus preventing heme from binding to antibody and/or antigen. The inhibitory capacity of the most potent compounds was substantially higher than that of chloroquine, a well-known heme binder. Some of the guanylhydrazone molecules were able to induce polyreactivity of the studied antibody themselves, possibly by a mechanism similar to heme. Results described here point to the conclusion that heme indeed must bind to an antibody to induce its polyreactivity, and that both π-stacking interactions and iron coordination contribute to the binding affinity, while certain structures, such as guanylhydrazones, can interfere with these processes.

Influence of variants in folate metabolism genes on 6-mercaptopurine induced toxicity during treatment for childhood acute lymphocytic leukemia

PURPOSE

To analyze influence of variants in TYMS, MTHFR, SLC19A1 and DHFR genes on 6-mercaptopurine (MP) induced toxicity during maintenance phase of treatment for childhood acute lymphocytic leukemia (ALL).

METHODS

One-hundred twenty-seven children with ALL that received maintenance therapy were involved in this study. All patients were treated according to Berlin-Frankfurt-Muenster (BFM) based protocols. Myelotoxicity and hepatotoxicity were evaluated using surrogate markers (median 6-MP dose, number of leukopenic episodes and levels of bilirubin and transaminases on each visit).

RESULTS

Higher number of leukopenic episodes, as a surrogate marker of 6-MP myelotoxicity, was found in carriers of TYMS 3R3R and 3R4R genotypes (p=0.067) as well as in TYMS 3R6bp+ (28bp VNTR, 6bp indel) haplotype carriers (p=0.015). Carriers of DHFR CATAG (-680, -675, -556, -464, -317) haplotype were also found to have higher number of leukopenic episodes (p=0.070). SLC19A1 c.80A allele (p=0.079) and TYMS 2R6bp+ (5'UTR VNTR, 6bp indel) haplotype carriers (p=0.078) had fewer leukopenic episodes. No difference in genotype frequencies between the control group of volunteered blood donors and childhood ALL patients was found.

CONCLUSIONS

Variants in TYMS, SLC19A1 and DHFR genes are potential biomarkers of myelotoxicity and could be used for 6-MP therapy individualization in maintenance phase of childhood ALL treatment, alongside with well-established TPMT variants.

Variants in TPMT, ITPA, ABCC4 and ABCB1 Genes As Predictors of 6-mercaptopurine Induced Toxicity in Children with Acute Lymphoblastic Leukemia

BACKGROUND

Acute lymphoblastic leukemia is the most common childhood malignancy. Optimal use of anti leukemic drugs has led to less toxicity and adverse reactions, and a higher survival rate. Thiopurine drugs, including 6-mercaptopurine, are mostly used as antileukemic medications in the maintenance phase of treatment for children with acute lymphoblastic leukemia. For those patients, TPMT genotype- tailored 6-mercaptopurine therapy is already implemented in the treatment protocols. We investigated the role of TPMT, ITPA, ABCC4 and ABCB1 genetic variants as predictors of outcome and 6-mercaptopurine induced toxicity during the maintenance phase of treatment in pediatric acute lymphoblastic leukemia.

METHODS

Sixty-eight children with acute lymphoblastic leukemia were enrolled in this study. Patients have been treated according to ALL IC-BFM 2002 or ALL IC-BFM 2009 protocols. Toxicity and adverse events have been monitored via surrogate markers (off-therapy weeks, episodes of leu - ko penia and average 6-mercaptopurine dose) and a prob- abilistic model was employed to predict overall 6-mercaptopurine related toxicity.

RESULTS

We confirmed that patients with acute lymphoblastic leukemia that carry inactive TPMT allele(s) require 6- mercaptopurine dose reduction. ITPA and ABCC4 genetic variants failed to show an association with 6-mercapto - purine induced toxicity during the maintenance phase. Carriers of ABCB1 variant allele experienced greater hepatotoxicity. The probabilistic model Neural net which considered all the analysed genetic variants was assessed to be the best prediction model. It was able to discriminate ALL patients with good and poor 6-mercaptopurin tolerance in 71% of cases (AUC=0.71).

CONCLUSIONS

This study contributes to the design of a panel of pharmacogenetic markers for predicting thiopurineinduced toxicity in pediatric ALL.

Children and adolescents with marginal zone lymphoma have an excellent prognosis with limited chemotherapy or a watch-and-wait strategy after complete resection

Data on management of pediatric marginal zone lymphoma (MZL) are scarce. This retrospective study assessed characteristics and outcome in 66 patients who were <18 years old. Forty-four (67%) had an extranodal MZL (EMZL), 21 (32%) a nodal MZL (NMZL), and one patient a splenic MZL. Thirty-three patients (50%) received a variable combination of adjuvant chemotherapy/immunotherapy/radiotherapy, while the remainder, including 20 of 21 with NMZL, entered an active observation period. Overall survival was excellent (98 ± 2%), although 11 patients relapsed (17%; NMZL, n = 1; EMZL, n = 10), seven after any therapy and four after complete resection only. In conclusion, outcome of NZML, in particular, seems to be excellent after (in)complete resection and observation only.

Non-Hodgkin lymphoma and pre-existing conditions: spectrum, clinical characteristics and outcome in 213 children and adolescents

Children and adolescents with pre-existing conditions such as DNA repair defects or other primary immunodeficiencies have an increased risk of non-Hodgkin lymphoma. However, large-scale data on patients with non-Hodgkin lymphoma and their entire spectrum of pre-existing conditions are scarce. A retrospective multinational study was conducted by means of questionnaires sent out to the national study groups or centers, by the two largest consortia in childhood non-Hodgkin lymphoma, the European Intergroup for Childhood non-Hodgkin Lymphoma, and the international Berlin-Frankfurt-Münster Study Group. The study identified 213 patients with non-Hodgkin lymphoma and a pre-existing condition. Four subcategories were established: a) cancer predisposition syndromes (n=124, 58%); b) primary immunodeficiencies not further specified (n=27, 13%); c) genetic diseases with no increased cancer risk (n=40, 19%); and d) non-classifiable conditions (n=22, 10%). Seventy-nine of 124 (64%) cancer predispositions were reported in groups with more than 20 patients: ataxia telangiectasia (n=32), Nijmegen breakage syndrome (n=26), constitutional mismatch repair deficiency (n=21). For the 151 patients with a known cancer risk, 5-year event-free survival and overall survival rates were 40%±4% and 51%±4%, respectively. Five-year cumulative incidences of progression/relapse and treatment-related death as a first event were 22%±4% and 24%±4%, respectively. Ten-year incidence of second malignancy was 24%±5% and 7-year overall survival of the 21 patients with a second malignancy was 41%±11%. Patients with non-Hodgkin lymphoma and pre-existing conditions have an inferior survival rate with a large proportion of therapy-related deaths compared to patients with non-Hodgkin lymphoma and no pre-existing conditions. They may require special vigilance when receiving standard or modified/reduced-intensity chemotherapy or when undergoing allogeneic stem cell transplantation.

Characterisation of general proteolytic, milk clotting and antifungal activity of Ficus carica latex during fruit ripening

BACKGROUND

The physiological role of fig latex is to protect the plant from pathogens. Latex is a rich source of proteases, predominantly ficin. Fig latex also contains collagenolytic protease and chitinolytic enzymes. Our aim was to investigate changes in protein composition, enzyme and antifungal activities of fig latex during fruit ripening.

RESULTS

Comparison of latex samples in different time periods showed a uniform increase of protein concentration in chronological order. The content of collagenolytic protease did not differ significantly in the latex samples, while the content of ficin decreased. Ficin-specific activity towards casein was the highest at the beginning of fruit development (about 80 U mg(-1)). Specific milk clotting activity increased as well as the abundance of casein band in the clots. Specific chitinolytic activity at the beginning of flowering was 6.5 times higher than the activity in the period when fruits are ripe. Antifungal activity is the most extensive in spring.

CONCLUSION

Ficin forms with different casein specificities are present in different proportions during fruit ripening, which is of importance for applications in the dairy industry. The protection mechanism against insects and fungi, which relies on chitinolytic activity, is the most important in the early phases of flowering and is replaced with other strategies over time.

Extreme hypertriglyceridemia in an infant with hemophagocytic lymphohistiocytosis and hydroxycobalamin deficiency

Introduction. Hemophagocytic lymphohistiocytosis (HLH) is a severe hyperinflammatory condition characterized by fever, cytopenias, hepatosplenomegaly and hemophagocytosis. HLH may be primary or secondary to infection, autoimmune disease or malignancy. Hypertriglyceridemia is a common abnormality in HLH and one of the HLH-2004 diagnostic criteria. Case Outline. We present an infant with severe hypotonia and hypoproteinemic edema who also had extreme hypertriglyceridemia (21 mmol/l) and was diagnosed with HLH based on six of eight HLH- 2004 criteria (fever, hepatosplenomegaly, bicytopenia, hypertriglyceridemia with hypofibrinogenemia, sIL-2R > 2400 IU/ml, hemophagocytosis). The presence of IgM antibodies to Epstein-Barr virus and cytomegalovirus indicated a probable infectious trigger. The child was cured by the HLH-2004 protocol for secondary HLH (consisting of dexamethasone and cyclosporine). He was also found to have low serum hydroxycobalamin levels, promptly corrected upon hydroxycobalamin administration. Conclusion. The presented case history underlines the need to ascertain the presence or absence of each of the eight HLH-2004 criteria in any patient suspected to suffer from HLH.

Colon carcinoma in a child treated with oxaliplatin and antiangiogenic treatment regimens

Colorectal carcinoma is an extremely rare tumor in childhood. Therefore, the role of adjuvant chemotherapy has not been adequately evaluated in children leading to limited data on safety profile and treatment response after application of novel drugs and novel targeted agents. In this report, we describe a case of colon adenocarcinoma in a 13-year-old girl treated with standard adult treatment as well as novel targeted therapy. This case report illustrates initial good disease control with FOLFOX therapy. On the other hand, targeted therapy revealed no improvement in disease control and good safety profile without significant adverse effects.

Late vitamin K deficiency bleeding in an infant with choledochal cyst

Infantile choledochal cyst (CC) usually presents as jaundice, vomiting, acholic stools, and hepatomegaly, and it can resemble biliary atresia. Although bleeding tendency is a rare clinical presentation of CC, it can be the first symptom, especially in infants less than 12 months of age. We report a case of a two-month-old infant with choledochal cyst presenting as late vitamin K deficiency bleeding (VKDB). Early recognition of diseases predisposing to VKDB and immediate investigation and treatment of warning bleeds help to prevent the worst consequences. Late VKDB is often the presenting feature of a serious underlying disease that may be recognized early. The sudden onset of bleeding tendency in infants with congenital liver or biliary tract disease may suggest not only biliary atresia but also, although extremely rare, CC. Early vitamin K administration leads to rapid normalization of hemostatic parameters, which enables major liver surgery.

Bone marrow findings in juvenile idiopathic arthritis

The diagnosis of juvenile idiopathic arthritis (JIA) is an exclusion one due to heterogeneous clinical presentation and lack of specific laboratory tests. The authors investigated bone marrow of 25 untreated children with JIA at the onset of the disease. Bone marrow smears were evaluated for cell populations as well as myelodysplastic features and compared to two control groups. The characteristic of bone marrow in JIA was myeloid hyperplasia and elevated plasmocyte count. There was no difference between JIA patients and control groups in terms of myelodysplastic features. These findings can be helpful in explaining hematological alterations in JIA.

Myeloid sarcoma presenting with bilateral proptosis and kidney infiltration

The authors describe a male infant with a history of transient pancytopenia who developed progressive bilateral proptosis associated with diffuse infiltration of the kidney and normal bone marrow. The histopathological examination of the kidney revealed diffuse infiltration of cells of myeloid origin with monocytic differentiation. Although orbital involvement by myeloid sarcoma, with or without concurrent acute myeloid leukemia, is well known, there are distinctive features in this patient that are not reported in the literature, namely bilateral proptosis and simultaneous presence of bilateral kidney infiltration, which enabled diagnosis.

Concordant in situ and in vitro data show that maternal cigarette smoking negatively regulates placental cytotrophoblast passage through the cell cycle

Maternal cigarette smoking is associated with fetal growth restriction and other pregnancy complications. To investigate possible mechanisms involving the placenta, we studied the morphology of first trimester chorionic villi from mothers who smoked. In mothers who smoked > 20 cigarettes/day, floating villi showed focal defects including an absence of cytotrophoblast stem cells and an abnormal thinning of the syncytium. Anchoring villi displayed a striking increase in the number of cytotrophoblast columns that failed to reach the uterus or degenerated in the intervillous space. Many samples showed a significant reduction in the number of anchoring villi. Also, the number of Ki67-positive cytotrophoblasts was dramatically decreased, indicating that fewer cells were in S phase of the mitotic cycle. Together, these results suggested premature depletion of the cytotrophoblast stem cell population. To test this hypothesis, we exposed anchoring villi from nonsmokers to nicotine in vitro and analyzed the effects on cytotrophoblast passage through the cell cycle. Nicotine (0.23 to 6.0 microM) negatively affected the expression of a number of cell cycle regulators/markers and BrdU incorporation, without discernable effects on apoptosis. These results link abnormal placental development secondary to maternal cigarette smoking to a substantial decrease in the mitotic potential of cytotrophoblasts.

The E2 region of HPV 16 in relation to different types of cervical lesions

The presence of the E2 region of HPV 16 was determined by the polymerase chain reaction in biopsy samples with different histopathological diagnoses. The absence of the E2 gene was observed in 17 of 30 cases examined. The E2 deletions were not confined exclusively to invasive carcinomas or to integrated viral forms. In the majority of cases, the course of cervical lesions was consistent with the state of the E2 gene.