Search

Persistent organic pollutants (POPs) are lipophilic, constant and bioaccumulative toxic compounds. In general, they are considered resistant to biological, photolytic, and chemical degradation with polychlorinated biphenyls (PCBs) belonging to these chemicals. PCBs were never produced in Serbia, but they were imported and mainly used in electrical equipment, transformers, and capacitors. Our study aimed to analyse sequential multi-stage aerobic/anaerobic microbial biodegradation of PCBs present in the river sediment from the area known for long-term pollution with these chemicals. The study with an autochthonous natural microbial community (NMC model system) and NMC augmented with allochthonous hydrocarbon-degrading (AHD) microorganisms (isolated from location contaminated with petroleum products) (NMC-AHD model system) was performed in order to estimate the potential of these microorganisms for possible use in future bioremediation treatment of these sites. The laboratory biodegradation study lasted 70 days, after which an overall >33 % reduction in the concentration of total PCBs was observed. This study confirmed the strong potential of the NMC for the reduction of the level of PCBs in the river sediment under alternating multi-stage aerobic/anaerobic conditions.

Optically active macromolecules, having a preferred- or single-handed helical conformation, play important roles in polymeric materials and in life. This article presents how helical polymers can be assessed from a view of chirality. These assessments, based on optical rotation (OR) and circular dichroism (CD) spectral measurements with associated information, include theoretical spectral calculations as well as chromatographic resolution. Specific applied examples are discussed for poly(9,9-dioctylfluorene-2,7-diyl) and derivatives, stereoregular polyolefins bearing centers of chirality in the side chain, isotactic poly(triphenylmethyl methacrylate), and π-stacked poly(dibenzofulvene). For more convincing establishment of a helix, it is important to correlate chiroptical properties with related information such as molar-mass effects, temperature effects, and chemical transformation effects on the properties. Helices of the polyolefins and poly(TrMA) were confirmed considering these aspects. In addition, comparison of chiroptical properties between the polymer in question and a monomeric unit model compound generally helps to confirm a helix. There are no general, reliable methods to quantify helical sense excess. On the other hand, absolute helical sense can be determined by comparing experimental and theoretical CD spectra as well as considering exciton coupling effects in CD spectra. The former method can be more generally applied for a wide range of polymers as far as a good model for calculations is designed, while the latter can be more conveniently and empirically applied for a certain class of polymer structures that are suited to exhibit exciton coupling without using computers.

Variation in the scanning strategy for β-type Ti alloys during additive manufacturing (AM) enables the fabrication of a singlecrystal-like microstructure possessing a crystallographic texture, in which the low-Young’s modulus- direction is aligned along a specific direction. Thus, metal biomaterial with low elasticity, comparable to the bone Young’s modulus, can be developed by AM, which will contribute to suppress the stress shielding of bone and prevent degradation of bone tissue anisotropy.

Chymotrypsin- or trypsin V- (a mixture of trypsin and chymotrypsin) digested β-lactoglobulin (BLG) peptides were prepared and were confirmed to have much less immunoglobulin (lg)G and lgE reactivity compared with intact BLG by IgG inhibition enzymelinked immunosorbent assay and IgE dot blotting. The lymphocyte responses to intact BLG and these peptides were examined using peripheral blood mononuclear cells (PBMCs) from 10 patients with cow's milk allergy. The PBMCs from most patients had lower lymphocyte responses to chymotrypsin- and trypsin V-digested BLG peptides than those to intact BLG. However, PBMCs from one and two patients retained significant proliferative responses to both peptides and to only the former peptide, respectively. Interferon-c production stimulated by chymotrypsin-digested peptides was still detectable in all five patients tested. Chymotrypsindigested BLG reduced lgE reactivity but still induced some lymphocyte responses.

Abstract Introduction Malignant pleural mesothelioma was once a rare finding but its incidence is increasing worldwide, most likely because of widespread exposure to asbestos. Although complete surgical resection is considered the only curative treatment, the results of surgery have shown a median survival time of only one year. In inoperable cases, chemotherapy, radiotherapy, and a combination of both have been considered as palliative therapy. Therefore, outcomes for inoperable cases have been poor. Here, we report the case of a long-term survivor treated with hyperthermia and chemotherapy. Case presentation A 61-year-old Japanese man with a performance status of 1 due to chest pain was referred to our hospital. He had a history of asbestos exposure for approximately five years. A computed tomography scan showed diffuse extensive right pleural thickening with small nodular lesions, and video-assisted thoracoscopy revealed tumor invasion of the ipsilateral chest wall muscles. The histopathologic findings were consistent with a diagnosis of malignant pleural mesothelioma (sarcomatoid type). The tumor was diagnosed as being stage cT3N0M0. Our patient refused any invasive therapies including surgery and radiotherapy, and was therefore treated with hyperthermia and systemic chemotherapy with agents such as cisplatin and irinotecan. He underwent three hyperthermia sessions and a single course of chemotherapy without any severe complications. One month after treatment, a follow-up computed tomography scan showed no definitive abnormality in the thoracic space. Our patient has subsequently survived without any evident disease for more than seven years. Conclusions The combination of hyperthermia and chemotherapy may be a novel and safe therapeutic option for malignant pleural mesothelioma, and can be considered for patients ineligible for radical treatment. Further clinical studies of the combination of hyperthermia and chemotherapy are needed to confirm the effects of this treatment on malignant pleural mesothelioma.

Abstract Introduction Chemotherapy and other systemic therapies are the primary treatments for patients with unresectable, locally advanced breast cancer. The clinical application of supportive care using Mohs paste has become widespread for the purpose of improving patients’ quality of life. Here, we report two cases of locally advanced breast cancer, for which the patients underwent radical surgery after a combination of systemic therapy and Mohs chemosurgery. Case presentations Patient 1 was a 90-year-old Japanese woman with right breast cancer diagnosed as stage IIIB (T4bN1M0). The treatment included Mohs paste application and hormonal therapies. Patient 2 was a 60-year-old Japanese woman with right breast cancer diagnosed as stage IIIB (T4cN2aM0). Her treatment included Mohs paste application, together with chemotherapy (four cycles of 5-fluorouracil, epirubicin, and cyclophosphamide, and four cycles of docetaxel). In both cases, a reduction in the primary tumor volume was observed, and radical mastectomy and axillary lymph node dissection were possible without relaxation incision or skin flap. Conclusion We report patients with no distant metastases who were able to undergo radical resection after a combination of systemic therapy and Mohs chemosurgery. For locally advanced breast cancer, Mohs chemosurgery, in addition to multidisciplinary treatment, is useful.

Abstract Background We evaluated the safety and validity of cholecystomucoclasis (CM) and compared its intraoperative characteristics with those of standard cholecystectomy (SC). Methods We enrolled 174 patients who underwent cholecystectomy and retrospectively evaluated the outcomes of patients in the SC and CM groups. Results Significant differences in age (71.1 vs. 61.9 years), American Society of Anesthesiologists physical status (ASA-PS), and serum C-reactive protein levels (CRP) (18.1 vs. 4.7 mg/dL) were observed between the CM and SC groups. Conversely, no significant differences were observed in the operation time (129 vs. 108 min), amount of blood loss (147 vs. 80 mL), intraoperative complications (0% vs. 5.7%), or duration of hospital stay (13.2 vs. 8.9 days) between the 2 groups. A high conversion rate (35.3%), postoperative complications (33%), and frequent drain insertions (94%) were observed in the CM group. Conclusions CM is a safe and valid surgical procedure and surgeons should not hesitate to transition to CM for patients who are of advanced age, in poor general condition (high ASA classification), or have high levels of serum CRP.

Abstract Background The treatment strategy of central lung tumors is not established. Intraluminal brachytherapy (ILBT) is widely used for palliative treatment of endobronchial tumors, however, it is also a promising option for curative treatment with limited data. This study evaluates the results after ILBT for endobronchial carcinoma. Method Sixteen-endobronchial carcinoma of 13 patients treated with ILBT in curative intent for 2000 to 2008 were retrospectively reviewed. ILBT using high dose rate 192 iridium thin wire system was performed with 5 Gy/fraction at mucosal surface. The patient age ranged from 57 to 82 years old with median 75 years old. The 16 lesions consisted of 13 central endobronchial cancers including 7 roentgenographically occult lung cancers and 3 of tracheal cancers. Of them, 10 lesions were treated with ILBT of median 20 Gy combined with external beam radiation therapy of median 45 Gy and 6 lesions were treated with ILBT alone of median 25 Gy. Results Median follow-up time was 32.5 months. Two-year survival rate and local control rate were 92.3% and 86.2%, respectively. Local recurrences were observed in 2 lesions. Three patients died due to lung cancer (1 patient) and intercurrent disease (2 patients). Complications greater than grade 2 were not observed except for one grade 3 dyspnea. Conclusions ILBT combined with or without EBRT might be a curative treatment option in inoperable endobronchial carcinoma patients with tolerable complication.

Abstract Background We conducted the present study to investigate the therapeutic effects of a combination treatment of alfacalcidol (ALF) and risedronate (RIS) on the bone mechanical properties of bone and calcium (Ca) metabolism using an ovariectomized (OVX) rat model of osteoporosis. Methods Female Wistar rats were OVX- or sham-operated at 40 weeks of age. Twelve weeks post-surgery, rats were randomized into seven groups: 1) sham + vehicle, 2) OVX + vehicle, 3) OVX + ALF 0.025 μg/kg/day, 4) OVX + ALF 0.05 μg, 5) OVX + RIS 0.3 mg, 6) OVX + RIS 3.0 mg, 7) OVX + ALF 0.025 μg + RIS 0.3 mg. Each drug was administered orally five times a week for 12 weeks. After treatment, we evaluated the mechanical properties of the lumbar vertebra and femoral midshaft. In the lumbar vertebra, structural and material analyses were performed using micro-computed tomography (micro-CT) and microbeam X-ray diffraction (micro-XRD), respectively. Biochemical markers in serum and urine were also determined. Results (1) With respect to improvement in the mechanical strength of the lumbar spine and the femoral midshaft, the combination treatment of ALF and RIS at their sub-therapeutic doses was more effective than each administered as a monotherapy; (2) In the suppression of bone resorption and the amelioration of microstructural parameters, the effects of ALF and RIS were considered to be independent and additive; (3) The improvement of material properties, such as microstructural parameters and the biological apatite (Bap) c-axis orientation, contributed to the reinforcement of spinal strength; and (4) The combination treatment of ALF and RIS normalized urinary Ca excretion, suggesting that this treatment ameliorated the changes in Ca metabolism. Conclusion These results demonstrate that the combination treatment of ALF and RIS at their sub-therapeutic doses can improve the mechanical properties of the spine as well as the femur and ameliorate changes in Ca metabolism in an animal model of osteoporosis, suggesting that the combination treatment of ALF and RIS has a therapeutic advantage over each monotherapy for the treatment of osteoporosis.

Abstract: Through the use of genetic sequencing, molecular variants driving autoimmunity are increasingly identified in patients with chronic and refractory immune cytopenias. With the goal of discovering genetic variants that predispose to pediatric immune thrombocytopenia (ITP) or increase risk for chronic disease, we conducted a genome-wide association study in a large multi-institutional cohort of pediatric patients with ITP. A total of 591 patients were genotyped using an Illumina Global Screening Array BeadChip. Six variants met genome-wide significance in comparison between children with ITP and a cohort of healthy children. One variant in NAV2 was inversely associated with ITP (adjusted odds ratio [aOR], 0.52; P = 3.2 × 10-11). Two other variants in close proximity to NKD1 were also inversely associated with ITP (aOR, 0.43; P = 8.86 × 10-15; aOR, 0.48; P = 1.84 × 10-16). These genes have been linked to the canonical Wnt signaling pathway. No variants met genome-wide significance in comparison of those with ITP that self-resolved in <1 year versus those who developed chronic ITP. This study identifies genetic variants that may contribute to ITP risk and raises a novel pathway with a potential role in ITP pathogenesis., (© 2024 by The American Society of Hematology. Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution. All other rights reserved.)

Abstract: There are no agreed upon terminology to define "refractory" pediatric immune thrombocytopenia (ITP). Guidelines are therefore limited to arbitrary and outdated definitions. The Pediatric ITP Consortium of North America held a meeting in 2023 to define this entity. With 100% agreement, the faculty established that pediatric ITP that is refractory to emergent therapy could be defined as no platelet response after treatment with all eligible emergent pharmacotherapies. With 100% agreement, the working group established that pediatric patients with ITP that continue to demonstrate high disease burden and/or no platelet response despite treatment with multiple classes of disease-modifying therapies represent a challenging subset of ITP. These patients are at higher risk of ongoing disease burden and merit additional investigation as well as consideration for clinical trials or novel therapies. Future efforts to define disease burden and disease response will be completed in collaboration with the ITP International Working Group., (© 2024 by The American Society of Hematology. Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution. All other rights reserved.)

Objective: Rheumatologic disease-associated hemophagocytic lymphohistiocytosis (HLH), a rare, life-threatening, systemic hyperinflammatory syndrome, occurs as a complication of underlying rheumatologic disease. Real-world evidence is lacking on emapalumab, a fully human monoclonal antibody that neutralizes the proinflammatory cytokine interferon-γ, approved for treating patients with primary HLH., Methods: REAL-HLH, a retrospective medical chart review study conducted across 33 US hospitals, assessed real-world treatment patterns and outcomes in patients with HLH treated with one or more dose of emapalumab between November 20, 2018, and October 31, 2021. Data are presented for the subset of patients with rheumatologic disease-associated HLH., Results: Fifteen of 105 patients (14.3%) had rheumatologic disease-associated HLH. Of these, nine (60.0%) had systemic juvenile idiopathic arthritis, and one (6.7%) had adult-onset Still disease. Median (range) age at HLH diagnosis was 5 (0.9-39) years. Most patients (9 of 15; 60.0%) initiated emapalumab in an intensive care unit. Emapalumab was most frequently initiated for treating refractory or recurrent (10 of 15; 66.7%) disease. Most patients received HLH-related therapies before (10 of 15; 66.7%) and concurrently with (15 of 15; 100.0%) emapalumab. Emapalumab-containing regimens stabilized or achieved physician-determined normalization of most laboratory parameters, including absolute neutrophil count and absolute lymphocyte count (13 of 14; 92.9%), chemokine ligand 9 (9 of 11; 81.8%), and platelets and alanine transaminase (11 of 14; 78.6%), and reduced glucocorticoid dose by 80%. Overall survival and 12-month survival probability from emapalumab initiation were 86.7%., Conclusion: Emapalumab-containing regimens stabilized or normalized most key laboratory parameters, reduced glucocorticoid dose, and were associated with low disease-related mortality, thereby demonstrating potential benefits in patients with rheumatologic disease-associated HLH., (© 2024 The Author(s). Arthritis & Rheumatology published by Wiley Periodicals LLC on behalf of American College of Rheumatology.)

Severe aplastic anemia (SAA) is a rare potentially fatal hematologic disorder. Although overall outcomes with treatment are excellent, there are variations in management approach, including differences in treatment between adult and pediatric patients. Certain aspects of treatment are under active investigation in clinical trials. Because of the rarity of the disease, some pediatric hematologists may have relatively limited experience with the complex management of SAA. The following recommendations reflect an up-to-date evidence-based approach to the treatment of children with relapsed or refractory SAA., (© 2024 The Authors. Pediatric Blood & Cancer published by Wiley Periodicals LLC.)

Severe aplastic anemia (SAA) is a rare potentially fatal hematologic disorder. Although overall outcomes with treatment are excellent, there are variations in management approach, including differences in treatment between adult and pediatric patients. Certain aspects of treatment are under active investigation in clinical trials. Because of the rarity of the disease, some pediatric hematologists may have relatively limited experience with the complex management of SAA. The following recommendations reflect an up-to-date evidence-based approach to the treatment of children with newly diagnosed SAA., (© 2024 The Authors. Pediatric Blood & Cancer published by Wiley Periodicals LLC.)

Background: Patients with telomere biology disorders (TBD) develop hepatic disease, including hepatitis, cirrhosis, and hepatopulmonary syndrome. No specific treatment exists for TBD-related liver disease, and the role of liver transplantation (LT) remains controversial. Our study objectives were to describe the clinical characteristics, management, and outcomes in patients with TBD-related liver disease, and their LT outcomes., Methods: Data from 83 patients with TBD-associated liver disease were obtained from 17 participating centers in the Clinical Care Consortium of Telomere-Associated Ailments and by self-report for our retrospective, multicenter, international cohort study., Results: Group A ("Advanced") included 40 patients with advanced liver disease. Of these, 20 underwent LT (Group AT). Group M ("Mild") included 43 patients not warranting LT evaluation, none of whom were felt to be medically unfit for liver transplantation. Supplemental oxygen requirement, pulmonary arteriovenous malformation, hepatopulmonary syndrome, and higher bilirubin and international normalized ratio values were associated with Group A. Other demographics, clinical manifestations, and laboratory findings were similar between groups. Six group A patients were declined for LT; 3 died on the waitlist. Median follow-up post-LT was 2.9 years (range 0.6-13.2 y). One-year survival post-LT was 73%. Median survival post-LT has not been reached. Group AT patients had improved survival by age compared to all nontransplant patients (log-rank test p = 0.02). Of 14 patients with pretransplant hypoxemia, 8 (57%) had improved oxygenation after transplant., Conclusions: LT recipients with TBD do not exhibit excessive posttransplant mortality, and LT improved respiratory status in 57%. A TBD diagnosis should not exclude LT consideration., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Association for the Study of Liver Diseases.)

Background and Objectives: Kaposiform hemangioendothelioma (KHE) and tufted angioma (TA) are rare vascular tumors in children historically associated with significant morbidity and mortality. This study was conducted to determine first-line therapy in the absence of available prospective clinical trials., Methods: Patients from 17 institutions diagnosed with KHE/TA between 2005 and 2020 with more than 6 months of follow-up were included. Response rates to sirolimus and vincristine were compared at 3 and 6 months. Durability of response and response to other treatment modalities were also evaluated., Results: Of 159 unique KHE/TA subjects, Kasabach-Merritt phenomenon (KMP) was present in 64 (40.3%), and only two patients were deceased (1.3%). Over 60% (n = 96) demonstrated treatment response at 3 months, and more than 70% (n = 114) by 6 months (no significant difference across groups). The vincristine group had higher radiologic response at 3 months compared to sirolimus (72.7% vs. 20%, p = .03), but there were no differences between these groups at 6 months. There were no differences in rates of recurrent or progressive disease between vincristine and sirolimus., Conclusions: In this large, multicenter cohort of 159 patients with KHE/TA, rates of KMP were consistent with historical literature, but the mortality rate (1.3%) was much lower. Overall treatment response rates were high (>70%), and there was no significant difference in treatment response or durability of disease comparing sirolimus to vincristine. Our results support individualized treatment decision plans depending on clinical scenario and patient/physician preferences. Response criteria and response rates reported here will be useful for guiding future treatment protocols for vascular tumors., (© 2023 Wiley Periodicals LLC.)

The MECOM gene encodes multiple protein isoforms that are essential for hematopoietic stem cell self-renewal and maintenance. Germline MECOM variants have been associated with congenital thrombocytopenia, radioulnar synostosis and bone marrow failure; however, the phenotypic spectrum of MECOM-associated syndromes continues to expand and novel pathogenic variants continue to be identified. We describe eight unrelated patients who add to the previously known phenotypes and genetic defects of MECOM-associated syndromes. As each subject presented with unique MECOM variants, the series failed to demonstrate clear genotype-to-phenotype correlation but may suggest a role for additional modifiers that affect gene expression and subsequent phenotype. Recognition of the expanded hematologic and non-hematologic clinical features allows for rapid molecular diagnosis, early identification of life-threatening complications, and improved genetic counseling for families. A centralized international publicly accessible database to share annotated MECOM variants would advance their clinical interpretation and provide a foundation to perform functional MECOM studies., (© 2023 Wiley Periodicals LLC.)

Central conducting lymphatic anomaly (CCLA) due to congenital maldevelopment of the lymphatics can result in debilitating and life-threatening disease with limited treatment options. We identified 4 individuals with CCLA, lymphedema, and microcystic lymphatic malformation due to pathogenic, mosaic variants in KRAS. To determine the functional impact of these variants and identify a targeted therapy for these individuals, we used primary human dermal lymphatic endothelial cells (HDLECs) and zebrafish larvae to model the lymphatic dysplasia. Expression of the p.Gly12Asp and p.Gly13Asp variants in HDLECs in a 2‑dimensional (2D) model and 3D organoid model led to increased ERK phosphorylation, demonstrating these variants activate the RAS/MAPK pathway. Expression of activating KRAS variants in the venous and lymphatic endothelium in zebrafish resulted in lymphatic dysplasia and edema similar to the individuals in the study. Treatment with MEK inhibition significantly reduced the phenotypes in both the organoid and the zebrafish model systems. In conclusion, we present the molecular characterization of the observed lymphatic anomalies due to pathogenic, somatic, activating KRAS variants in humans. Our preclinical studies suggest that MEK inhibition should be studied in future clinical trials for CCLA due to activating KRAS pathogenic variants.

Acquired aplastic anemia (AA) is caused by autoreactive T cell-mediated destruction of early hematopoietic cells. Somatic loss of human leukocyte antigen (HLA) class I alleles was identified as a mechanism of immune escape in surviving hematopoietic cells of some patients with AA. However, pathogenicity, structural characteristics, and clinical impact of specific HLA alleles in AA remain poorly understood. Here, we evaluated somatic HLA loss in 505 patients with AA from 2 multi-institutional cohorts. Using a combination of HLA mutation frequencies, peptide-binding structures, and association with AA in an independent cohort of 6,323 patients from the National Marrow Donor Program, we identified 19 AA risk alleles and 12 non-risk alleles and established a potentially novel AA HLA pathogenicity stratification. Our results define pathogenicity for the majority of common HLA-A/B alleles across diverse populations. Our study demonstrates that HLA alleles confer different risks of developing AA, but once AA develops, specific alleles are not associated with response to immunosuppression or transplant outcomes. However, higher pathogenicity alleles, particularly HLA-B*14:02, are associated with higher rates of clonal evolution in adult patients with AA. Our study provides insights into the immune pathogenesis of AA, opening the door to future autoantigen identification and improved understanding of clonal evolution in AA.

Objective: To evaluate the effect of the RAS-MAPK pathway inhibitor trametinib on medically refractory chylous effusions in 3 hospitalized patients with Noonan syndrome., Study Design: Pharmacologic MEK1/2 inhibition has been used to treat conditions associated with Noonan syndrome, given that activation of RAS-MAPK pathway variants leads to downstream MEK activation. We describe our experience with 3 patients with Noonan syndrome (owing to variants in 3 distinct genes) and refractory chylous effusions treated successfully with MEK inhibition. A monitoring protocol was established to standardize medication dosing and monitoring of outcome measures., Results: Subjects demonstrated improvement in lymphatic leak with additional findings of improved growth and normalization of cardiac and hematologic measurements. Trametinib was administered safely, with only moderate skin irritation in 1 subject., Conclusions: Improvements in a variety of quantifiable measurements highlight the potential utility of MEK1/2 inhibition in patients with Noonan syndrome and life-threatening lymphatic disease. Larger, prospective studies are needed to confirm efficacy and assess long-term safety., (Published by Elsevier Inc.)

Detailed genomic and epigenomic analyses of MECOM (the MDS1 and EVI1 complex locus) have revealed that inversion or translocation of chromosome 3 drives inv(3)/t(3;3) myeloid leukemias via structural rearrangement of an enhancer that upregulates transcription of EVI1. Here, we identify a novel, previously unannotated oncogenic RNA-splicing derived isoform of EVI1 that is frequently present in inv(3)/t(3;3) acute myeloid leukemia (AML) and directly contributes to leukemic transformation. This EVI1 isoform is generated by oncogenic mutations in the core RNA splicing factor SF3B1, which is mutated in >30% of inv(3)/t(3;3) myeloid neoplasm patients and thereby represents the single most commonly cooccurring genomic alteration in inv(3)/t(3;3) patients. SF3B1 mutations are statistically uniquely enriched in inv(3)/t(3;3) myeloid neoplasm patients and patient-derived cell lines compared with other forms of AML and promote mis-splicing of EVI1 generating an in-frame insertion of 6 amino acids at the 3' end of the second zinc finger domain of EVI1. Expression of this EVI1 splice variant enhanced the self-renewal of hematopoietic stem cells, and introduction of mutant SF3B1 in mice bearing the humanized inv(3)(q21q26) allele resulted in generation of this novel EVI1 isoform in mice and hastened leukemogenesis in vivo. The mutant SF3B1 spliceosome depends upon an exonic splicing enhancer within EVI1 exon 13 to promote usage of a cryptic branch point and aberrant 3' splice site within intron 12 resulting in the generation of this isoform. These data provide a mechanistic basis for the frequent cooccurrence of SF3B1 mutations as well as new insights into the pathogenesis of myeloid leukemias harboring inv(3)/t(3;3)., (© 2022 by The American Society of Hematology.)

Congenital lymphatic leak may develop in patients with maldeveloped lymphatics and result in life-threatening fluid and electrolyte imbalance, protein deficiency, and immunodeficiency. Rapid diagnosis and therapy are necessary to prevent these complications; however, the field lacks clinical trials to support standardized diagnostic treatment guidelines. We present our current multidisciplinary approach to the diagnosis and management of congenital lymphatic leak including chylous pleural effusions and ascites. Depending on the rate of lymphatic leak, therapy can range from observation with nutritional modifications to surgical and interventional procedures aimed to reduce lymphatic drainage. Modalities to image central and peripheral lymphatics have advanced considerably. Genetic variants and subsequent targets that drive lymphatic maldevelopment have expanded the repertoire of possible pharmacotherapeutic options., (© 2021 Wiley Periodicals LLC.)

The timely identification of germline genetic causes of pediatric bone marrow failure (BMF) impacts medical screening practices, family counseling, therapeutic decision-making, and risk of progression to myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML). At diagnosis, treatment decisions need to be made quickly to mitigate risks associated with profound cytopenias. As genetic testing options are rapidly evolving, an efficient multi-disciplinary approach and algorithm, including early involvement of a genetics team, is needed to expedite diagnosis and therapeutic decision-making. This process aids in the identification of appropriate candidates for molecular genetic testing. We present our single center experience reviewing the implementation of genetic counseling and a diagnostic and therapeutic algorithm used to guide genetic evaluation of pediatric BMF. Disease-specific next-generation sequencing (NGS) panels were most often pursued in patients who presented with a clinical phenotype consistent with a known inherited BMF syndrome and when trying to reduce incidental or uninformative results. Broader BMF NGS panels were most often utilized when unable to narrow the suspected etiology to a single disorder. Whole exome sequencing helped with optimizing treatment decision-making in higher risk children with BMF who required expedited hematopoietic stem cell transplantation. The experience has led to improvements to our process for evaluating patients with BMF., (© 2021 National Society of Genetic Counselors.)

Shwachman-Diamond syndrome (SDS) is an inherited bone marrow failure syndrome with leukemia predisposition. An understanding of the hematologic complications of SDS with age could guide clinical management, but data are limited for this rare disease. We conducted a cohort study of 153 subjects from 143 families with confirmed biallelic SBDS mutations enrolled on the North American Shwachman Diamond Registry or Bone Marrow Failure Registry. The SBDS c.258 + 2T>C variant was present in all but 1 patient. To evaluate the association between blood counts and age, 2146 blood counts were analyzed for 119 subjects. Absolute neutrophil counts were positively associated with age (P < .0001). Hemoglobin was also positively associated with age up to 18 years (P < .0001), but the association was negative thereafter (P = .0079). Platelet counts and marrow cellularity were negatively associated with age (P < .0001). Marrow cellularity did not correlate with blood counts. Severe marrow failure necessitating transplant developed in 8 subjects at a median age of 1.7 years (range, 0.4-39.5), with 7 of 8 requiring transplant prior to age 8 years. Twenty-six subjects (17%) developed a myeloid malignancy (16 myelodysplasia and 10 acute myeloid leukemia) at a median age of 12.3 years (range, 0.5-45.0) and 28.4 years (range, 14.4-47.3), respectively. A lymphoid malignancy developed in 1 patient at the age of 16.9 years. Hematologic complications were the major cause of mortality (17/20 deaths; 85%). These data inform surveillance of hematologic complications in SDS., (© 2022 by The American Society of Hematology. Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution. All other rights reserved.)

The North American Pediatric Aplastic Anemia Consortium (NAPAAC) is a group of pediatric hematologist-oncologists, hematopathologists, and bone marrow transplant physicians from 46 institutions in North America with interest and expertise in aplastic anemia, inherited bone marrow failure syndromes, and myelodysplastic syndromes. The NAPAAC Bone Marrow Failure Diagnosis and Care Guidelines Working Group was established with the charge of harmonizing the approach to the diagnostic workup of aplastic anemia in an effort to standardize best practices in the field. This document outlines the rationale for initial evaluations in pediatric patients presenting with signs and symptoms concerning for severe aplastic anemia., (© 2021 Wiley Periodicals LLC.)

To understand the mechanisms that mediate germline genetic leukemia predisposition, we studied the inherited ribosomopathy Shwachman-Diamond syndrome (SDS), a bone marrow failure disorder with high risk of myeloid malignancies at an early age. To define the mechanistic basis of clonal hematopoiesis in SDS, we investigate somatic mutations acquired by patients with SDS followed longitudinally. Here we report that multiple independent somatic hematopoietic clones arise early in life, most commonly harboring heterozygous mutations in EIF6 or TP53. We show that germline SBDS deficiency establishes a fitness constraint that drives selection of somatic clones via two distinct mechanisms with different clinical consequences. EIF6 inactivation mediates a compensatory pathway with limited leukemic potential by ameliorating the underlying SDS ribosome defect and enhancing clone fitness. TP53 mutations define a maladaptive pathway with enhanced leukemic potential by inactivating tumor suppressor checkpoints without correcting the ribosome defect. Subsequent development of leukemia was associated with acquisition of biallelic TP53 alterations. These results mechanistically link leukemia predisposition to germline genetic constraints on cellular fitness, and provide a rational framework for clinical surveillance strategies.

The field of vascular anomalies has grown tremendously in the last few decades with the identification of key molecular pathways and genetic mutations that drive the formation and progression of vascular anomalies. Understanding these pathways is critical for the classification of vascular anomalies, patient care, and development of novel therapeutics. The goal of this review is to provide a basic understanding of the classification of vascular anomalies and knowledge of their underlying molecular pathways. Here we provide an organizational framework for phenotype/genotype correlation and subsequent development of a diagnostic and treatment roadmap. With the increasing importance of genetics in the diagnosis and treatment of vascular anomalies, we highlight the importance of clinical geneticists as part of a comprehensive multidisciplinary vascular anomalies team., (Copyright © 2020 Borst, Nakano, Blei, Adams and Duis.)

Background: Myelodysplastic syndromes (MDS) represent a group of clonal hematopoietic stem cell disorders that commonly progress to acute myeloid leukemia (AML). The diagnostics, prognostics, and treatment of adult MDS are established but do not directly translate to children and adolescents. Pediatric MDS is a rare disease, characterized by unique cytogenetics and histology compared with adult MDS, and often arises secondary to germline predisposition or cytotoxic exposures. Our objective was to highlight aspects of diagnosis/management that would benefit from further systematic review toward the development of clinical practice guidelines for pediatric MDS., Procedure: The North American Pediatric Aplastic Anemia Consortium (NAPAAC) is composed of collaborative institutions with a strong interest in pediatric bone marrow failure syndromes and hematologic malignancies. The NAPAAC MDS working group developed a national survey distributed to 35 NAPAAC institutions to assess data on (1) clinical presentation of pediatric MDS, (2) diagnostic evaluation, (3) criteria for diagnosis, (4) supportive care and treatment decisions, and (5) role of hematopoietic stem cell transplantation (HSCT)., Results: Twenty-eight of 35 institutions returned the survey. Most centers agreed on a common diagnostic workup, though there was considerable variation regarding the criteria for diagnosis. Although there was consensus on supportive care, treatment strategies, including the role of cytoreduction and HSCT, varied across centers surveyed., Conclusions: There is lack of national consensus on diagnosis and treatment of pediatric MDS. This survey identified key aspects of MDS management that will warrant systematic review toward the goal of developing national clinical practice guidelines for pediatric MDS., (© 2020 Wiley Periodicals LLC.)

Background: Data to inform surveillance and treatment for leukaemia predisposition syndromes are scarce and recommendations are largely based on expert opinion. This study aimed to investigate the clinical features and outcomes of patients with myelodysplastic syndrome or acute myeloid leukaemia and Shwachman-Diamond syndrome, an inherited bone marrow failure disorder with high risk of developing myeloid malignancies., Methods: We did a multicentre, retrospective, cohort study in collaboration with the North American Shwachman-Diamond Syndrome Registry. We reviewed patient medical records from 17 centres in the USA and Canada. Patients with a genetic (biallelic mutations in the SBDS gene) or clinical diagnosis (cytopenias and pancreatic dysfunction) of Shwachman-Diamond syndrome who developed myelodysplastic syndrome or acute myeloid leukaemia were eligible without additional restriction. Medical records were reviewed between March 1, 2001, and Oct 5, 2017. Masked central review of bone marrow pathology was done if available to confirm leukaemia or myelodysplastic syndrome diagnosis. We describe the clinical features and overall survival of these patients., Findings: We initially identified 37 patients with Shwachman-Diamond syndrome and myelodysplastic syndrome or acute myeloid leukaemia. 27 patients had samples available for central pathology review and were reclassified accordingly (central diagnosis concurred with local in 15 [56%] cases), 10 had no samples available and were classified based on the local review data, and 1 patient was excluded at this stage as not eligible. 36 patients were included in the analysis, of whom 10 (28%) initially presented with acute myeloid leukaemia and 26 (72%) initially presented with myelodysplastic syndrome. With a median follow-up of 4·9 years (IQR 3·9-8·4), median overall survival for patients with myelodysplastic syndrome was 7·7 years (95% CI 0·8-not reached) and 0·99 years (95% CI 0·2-2·4) for patients with acute myeloid leukaemia. Overall survival at 3 years was 11% (95% CI 1-39) for patients with leukaemia and 51% (29-68) for patients with myelodysplastic syndrome. Management and surveillance were variable. 18 (69%) of 26 patients with myelodysplastic syndrome received upfront therapy (14 haematopoietic stem cell transplantation and 4 chemotherapy), 4 (15%) patients received no treatment, 2 (8%) had unavailable data, and 2 (8%) progressed to acute myeloid leukaemia before receiving treatment. 12 patients received treatment for acute myeloid leukaemia-including the two patients initially diagnosed with myelodysplastic who progressed- two (16%) received HSCT as initial therapy and ten (83%) received chemotherapy with intent to proceed with HSCT. 33 (92%) of 36 patients (eight of ten with leukaemia and 25 of 26 with myelodysplastic syndrome) were known to have Shwachman-Diamond syndrome before development of a myeloid malignancy and could have been monitored with bone marrow surveillance. Bone marrow surveillance before myeloid malignancy diagnosis was done in three (33%) of nine patients with leukaemia for whom surveillance status was confirmed and 11 (46%) of 24 patients with myelodysplastic syndrome. Patients monitored had a 3-year overall survival of 62% (95% CI 32-82; n=14) compared with 28% (95% CI 10-50; n=19; p=0·13) without surveillance. Six (40%) of 15 patients with available longitudinal data developed myelodysplastic syndrome in the setting of stable blood counts., Interpretation: Our results suggest that prognosis is poor for patients with Shwachman-Diamond syndrome and myelodysplastic syndrome or acute myeloid leukaemia owing to both therapy-resistant disease and treatment-related toxicities. Improved surveillance algorithms and risk stratification tools, studies of clonal evolution, and prospective trials are needed to inform effective prevention and treatment strategies for leukaemia predisposition in patients with Shwachman-Diamond syndrome., Funding: National Institute of Health., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Quality of response to immunosuppressive therapy and long-term outcomes for pediatric severe aplastic anemia remain incompletely characterized. Contemporary evidence to inform treatment of relapsed or refractory severe aplastic anemia for pediatric patients is also limited. The clinical features and outcomes for 314 children treated from 2002 to 2014 with immunosuppressive therapy for acquired severe aplastic anemia were analyzed retrospectively from 25 institutions in the North American Pediatric Aplastic Anemia Consortium. The majority of subjects (n=264) received horse anti-thymocyte globulin (hATG) plus cyclosporine (CyA) with a median 61 months follow up. Following hATG/CyA, 71.2% (95%CI: 65.3,76.6) achieved an objective response. In contrast to adult studies, the quality of response achieved in pediatric patients was high, with 59.8% (95%CI: 53.7,65.8) complete response and 68.2% (95%CI: 62.2,73.8) achieving at least a very good partial response with a platelet count ≥50×10 9 L. At five years post-hATG/CyA, overall survival was 93% (95%CI: 89,96), but event-free survival without subsequent treatment was only 64% (95%CI: 57,69) without a plateau. Twelve of 171 evaluable patients (7%) acquired clonal abnormalities after diagnosis after a median 25.2 months (range: 4.3-71 months) post treatment. Myelodysplastic syndrome or leukemia developed in 6 of 314 (1.9%). For relapsed/refractory disease, treatment with a hematopoietic stem cell transplant had a superior event-free survival compared to second immunosuppressive therapy treatment in a multivariate analysis (HR=0.19, 95%CI: 0.08,0.47; P =0.0003). This study highlights the need for improved therapies to achieve sustained high-quality remission for children with severe aplastic anemia., (Copyright© 2019 Ferrata Storti Foundation.)

Background: Lymphatic malformations (LMs) are congenital and arise from errors in vascular embryogenesis. LMs are categorized by cyst size as microcystic, macrocystic, or combined. Abdominal LMs are rare. Surgical resection of abdominal LMs has been the mainstay of therapy, but recurrence and morbidity are high. We sought to determine the effectiveness of sclerotherapy treatment for abdominal LM., Methods: A single-center, retrospective review from 2014 to 2018 was conducted evaluating pediatric patients with abdominal LM., Results: Ten patients were included, n = 9 had macrocystic LM and one patient had combined disease. The average age at first treatment was 6.8 y. The most common presenting symptoms were abdominal distention, pain, infection, and anemia. Preprocedural imaging was performed for all patients; median pretreatment volume was 1572.9 cm 3 (range, 67.2-13,226.4). LMs were accessed using ultrasound guidance and injected with opacified doxycycline. Patients received a mean of 7.1 sclerotherapy injections. Complications included intraperitoneal doxycycline extravasation (n = 1), managed conservatively, and LM infection (n = 1), treated with intravenous antibiotics and drainage. One patient went on to surgical resection due to inability gain stable intracystic access; follow-up ultrasonography showed no recurrence. Postprocedural imaging was available in n = 8. Volume decreased by 96.7% after sclerotherapy. The median remaining volume was 0 cm 3 (range, 0-599.7) (P = 0.016). Postsclerotherapy magnetic resonance imaging was obtained in n = 6, with complete resolution in 83.3%. All patients had resolution of presenting symptoms. Follow-up duration was 12.3 mo., Conclusions: Initial results demonstrate that sclerotherapy is an effective and durable treatment for symptom resolution and volume reduction of abdominal LM., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The presence of a vascular anomaly suggests that capillaries, veins, arteries, and/or lymphatic vessels have demonstrated abnormal development and growth. Often dilated and misshaped, these vessels augment normal flow of blood and lymphatic fluids that increases the overall risk to develop intralesional thrombosis. Abnormal endothelial and lymphoendothelial cells activate hemostasis and hyperfibrinolytic pathways through poorly understood mechanisms, which contribute to the development of localized intravascular coagulopathy. Vascular malformations, tumors, and complex combined syndromes demonstrate varying degrees of prothrombotic activity and consumptive coagulopathy depending on the vessels involved and the pattern and extent of abnormal growth. The clinical impact of venous thromboembolism in pediatric vascular anomalies varies from painful syndromes that disrupt quality of life to life-threatening embolic disease. There remains little literature on the study, evaluation, and treatment of thrombosis in pediatric vascular anomalies. However, there have been great advances in our ability to image complex lesions, to surgically and interventionally augment disease, and to provide enhanced supportive care including patient education, compression therapy, and strategic use of anticoagulation.

Infiltration of T cells in breast tumors correlates with improved survival of patients with breast cancer, despite relatively few mutations in these tumors. To determine if T-cell specificity can be harnessed to augment immunotherapies of breast cancer, we sought to identify the alpha-beta paired T-cell receptors (TCRs) of tumor-infiltrating lymphocytes shared between multiple patients. Because TCRs function as heterodimeric proteins, we used an emulsion-based RT-PCR assay to link and amplify TCR pairs. Using this assay on engineered T-cell hybridomas, we observed ∼85% accurate pairing fidelity, although TCR recovery frequency varied. When we applied this technique to patient samples, we found that for any given TCR pair, the dominant alpha- or beta-binding partner comprised ∼90% of the total binding partners. Analysis of TCR sequences from primary tumors showed about fourfold more overlap in tumor-involved relative to tumor-free sentinel lymph nodes. Additionally, comparison of sequences from both tumors of a patient with bilateral breast cancer showed 10% overlap. Finally, we identified a panel of unique TCRs shared between patients' tumors and peripheral blood that were not found in the peripheral blood of controls. These TCRs encoded a range of V, J, and complementarity determining region 3 (CDR3) sequences on the alpha-chain, and displayed restricted V-beta use. The nucleotides encoding these shared TCR CDR3s varied, suggesting immune selection of this response. Harnessing these T cells may provide practical strategies to improve the shared antigen-specific response to breast cancer.

Although sialic acids have a key role in many aspects of human biology, the expression of polysialic acid (PSA) in human tissues is thought to be relatively rare. We identified a derivative of PSA called neuraminic acid-containing PSA or NeuPSA that was highly expressed in primary human melanoma tumors and in several cancer cell lines. Moreover, anti-NeuPSA antibodies could induce apoptosis of cancer cells. However, little was known about NeuPSA expression in normal or diseased tissues. In this study we investigated the complete expression profile of NeuPSA in human tissues and a few primary tumors using the anti-NeuPSA monoclonal antibody, SEAM 3. Almost every human tissue tested spanning a representative sample of all organ types was positive for SEAM 3 binding. Specificity of SEAM 3 binding was established by inhibition with NeuPSA but not closely related meningococcal C polysaccharide and loss of SEAM 3 binding when specimens were treated with periodate at high pH, which specifically destroys NeuPSA. Only subsets of cells in each specimen stained positive, and the relative staining between tissues was variable. The distribution and amount of NeuPSA antigen in tissues was correlated with known levels of polysialyltransferase PST or STX expression. The majority of anti-NeuPSA binding occurred intracellularly in the cytoplasm of cells. Tumors generally exhibited considerably increased staining compared with corresponding normal tissues. Identifying the diverse tissue distribution and intracellular location of NeuPSA provides a foundation for investigating the functional role of NeuPSA in human health and disease.