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This article has been retracted. Please see the Retraction Notice for more detail: https://doi.org/10.1007/s11095-020-02971-0.
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BACKGROUND: Benign ethnic neutropenia (BEN), defined by neutrophil count <1.5â¯k/µL in the absence of other causes, is an asymptomatic condition more commonly observed in individuals of African ancestry. However, the natural history of this condition has been less well described. METHODS: Individuals with BEN were retrospectively identified by chart review or referral to hematology clinics. They were then invited to enroll in a prospective natural history study. Retrospective and prospective clinical and laboratory data were combined for descriptive analyses. FINDINGS: 46 participants, younger and older adults from 2 institutions, had BEN. Hypertension was reported in 30%, musculoskeletal disorders in 15%, and upper respiratory infection in 33% of these adults. Their leukopenia resulted from isolated neutropenia, ranging from 1000 and 1500â¯cells/µL. The severity of infections was mild and the frequency was similar to other healthy individuals in the ambulatory clinic. INTERPRETATION: In this group of BEN participants, their leukopenia was stable over time, and they had low rates of infections or common medical disorders, confirming the benign nature of this condition. The presence of BEN in children, younger adults, and older adults suggest a hereditary pattern for BEN.
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Población Negra , Neutropenia/epidemiología , Adolescente , Adulto , Anciano , Niño , Comorbilidad , Femenino , Humanos , Recuento de Leucocitos , Masculino , Persona de Mediana Edad , Neutropenia/complicaciones , Neutropenia/diagnóstico , Neutropenia/terapia , Neutrófilos , Vigilancia de la Población , Estudios Retrospectivos , Adulto JovenRESUMEN
We report a case of Streptococcus suis human disease in Ontario, Canada, caused by a serotype 2 strain genotypically similar to those commonly isolated from pigs in North America. Initially, the isolate was misidentified as a viridans group Streptococcus. Human S. suis infections may be underdiagnosed in North America.
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Filogenia , Infecciones Estreptocócicas/transmisión , Streptococcus suis/clasificación , Enfermedades de los Porcinos/transmisión , Anciano , Animales , Antibacterianos/uso terapéutico , Ceftriaxona/uso terapéutico , Agricultores , Humanos , Inmunoglobulinas Intravenosas/uso terapéutico , Masculino , Ontario , Serogrupo , Infecciones Estreptocócicas/diagnóstico , Infecciones Estreptocócicas/tratamiento farmacológico , Infecciones Estreptocócicas/microbiología , Streptococcus suis/inmunología , Streptococcus suis/aislamiento & purificación , Porcinos , Enfermedades de los Porcinos/microbiología , Resultado del TratamientoRESUMEN
BACKGROUND: Post-transplant lymphoproliferative disorders (PTLD) are a potentially fatal group of neoplasms arising in an immunodeficient environment. Although the cornerstone of treatment is reduced immunosuppression (RI), advanced cases often warrant treatment with chemoimmunotherapy. The chemoimmunotherapy regimen of dose-adjusted (DA)-EPOCH-R is superior to R-CHOP in HIV associated aggressive lymphomas, suggesting that it might also be favorable in the setting of PTLD. METHODS: We performed a retrospective analysis of patients with advanced monomorphic PTLD treated with first line DA-EPOCH-R in addition to RI at our institution from 2003-2016. RESULTS: Seven patients were included. Mean age was 51 and mean time from transplant to diagnosis was 71 months. Six of the seven patients received a kidney transplant, six had stage III or IV disease, six had tumors that were EBV positive, and six completed therapy. All six patients who completed therapy achieved a complete response. Mean PFS and OS were 46.6 and 52.6 months, respectively. Treatment was well-tolerated with no significant treatment related morbidity or mortality. CONCLUSIONS: Our findings support several observations in the literature that DA-EPOCH-R is efficacious and well-tolerated for the treatment of advanced, monomorphic PTLD.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Trastornos Linfoproliferativos/tratamiento farmacológico , Trastornos Linfoproliferativos/etiología , Trasplante de Órganos/efectos adversos , Adulto , Anciano , Ciclofosfamida/uso terapéutico , Doxorrubicina/uso terapéutico , Etopósido/uso terapéutico , Resultado Fatal , Femenino , Humanos , Terapia de Inmunosupresión , Trastornos Linfoproliferativos/diagnóstico , Trastornos Linfoproliferativos/mortalidad , Masculino , Persona de Mediana Edad , Prednisona/uso terapéutico , Estudios Retrospectivos , Rituximab/administración & dosificación , Resultado del Tratamiento , Vincristina/uso terapéuticoAsunto(s)
Leucemia Linfocítica Crónica de Células B/patología , Linfoma de Células B de la Zona Marginal/patología , Células Plasmáticas/patología , Neoplasias Cutáneas/patología , Anciano de 80 o más Años , Antineoplásicos Inmunológicos/uso terapéutico , Biopsia , Diferenciación Celular , Diagnóstico Diferencial , Humanos , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/inmunología , Linfoma de Células B de la Zona Marginal/genética , Linfoma de Células B de la Zona Marginal/inmunología , Masculino , Células Plasmáticas/inmunología , Valor Predictivo de las Pruebas , Rituximab/uso terapéutico , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/inmunología , Resultado del TratamientoRESUMEN
Patients with cancer are at increased risk for venous thromboembolism (VTE). An online survey to measure PE/DVT terminology awareness and understanding of VTE risks revealed 24% and 15% of the 500 cancer patients surveyed had heard of term DVT/PE; 19% and 17% could name signs/ symptoms of DVT/PE; 3% recognized cancer treatments as risk factors for DVT/PE. Only 25% of the patients received prevention education from providers; <50% received VTE prophylaxis. Cancer patient awareness of VTE terminology and cancer and/or its treatment as risk for VTE is low. More effective patient/physician dialogue about VTE risk and thromboprophylaxis is needed.
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Neoplasias/complicaciones , Embolia Pulmonar/epidemiología , Embolia Pulmonar/etiología , Trombosis de la Vena/epidemiología , Trombosis de la Vena/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Tromboembolia Venosa/epidemiología , Tromboembolia Venosa/etiologíaRESUMEN
BACKGROUND: Although well-established for suspected lower limb deep venous thrombosis, an algorithm combining a clinical decision score, d-dimer testing, and ultrasonography has not been evaluated for suspected upper extremity deep venous thrombosis (UEDVT). OBJECTIVE: To assess the safety and feasibility of a new diagnostic algorithm in patients with clinically suspected UEDVT. DESIGN: Diagnostic management study. (ClinicalTrials.gov: NCT01324037) SETTING: 16 hospitals in Europe and the United States. PATIENTS: 406 inpatients and outpatients with suspected UEDVT. MEASUREMENTS: The algorithm consisted of the sequential application of a clinical decision score, d-dimer testing, and ultrasonography. Patients were first categorized as likely or unlikely to have UEDVT; in those with an unlikely score and normal d-dimer levels, UEDVT was excluded. All other patients had (repeated) compression ultrasonography. The primary outcome was the 3-month incidence of symptomatic UEDVT and pulmonary embolism in patients with a normal diagnostic work-up. RESULTS: The algorithm was feasible and completed in 390 of the 406 patients (96%). In 87 patients (21%), an unlikely score combined with normal d-dimer levels excluded UEDVT. Superficial venous thrombosis and UEDVT were diagnosed in 54 (13%) and 103 (25%) patients, respectively. All 249 patients with a normal diagnostic work-up, including those with protocol violations (n = 16), were followed for 3 months. One patient developed UEDVT during follow-up, for an overall failure rate of 0.4% (95% CI, 0.0% to 2.2%). LIMITATIONS: This study was not powered to show the safety of the substrategies. d-Dimer testing was done locally. CONCLUSION: The combination of a clinical decision score, d-dimer testing, and ultrasonography can safely and effectively exclude UEDVT. If confirmed by other studies, this algorithm has potential as a standard approach to suspected UEDVT. PRIMARY FUNDING SOURCE: None.
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Algoritmos , Técnicas de Apoyo para la Decisión , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Ultrasonografía Doppler en Color , Trombosis Venosa Profunda de la Extremidad Superior/diagnóstico , Estudios de Factibilidad , Humanos , Probabilidad , Estudios Prospectivos , Trombosis Venosa Profunda de la Extremidad Superior/diagnóstico por imagenRESUMEN
Cold agglutinins produced in the setting of B cell neoplasms, such as lymphoplasmacytic lymphoma and plasma cell myeloma, can mediate autoimmune haemolytic anemia. Transfusion of these patients can exacerbate cold agglutinin-mediated haemolysis. Moreover, the workup for these reactions represents a diagnostic challenge due in part to false negative direct antiglobulin tests (DATs). Here, we report an anaemic patient who after a red blood cell (RBC) transfusion performed without blood warming, experienced a DAT-negative haemolytic transfusion reaction, and was later diagnosed with IgA-multiple myeloma, which showed an uncommon granular pattern by CD138 immunohistochemistry. Extensive workup excluded other diagnostic possibilities, including the presence of Donath-Landsteiner antibodies and cryoglobulins. Successful treatment with CyBorD (cyclophosphamide, bortezomib and dexamethasone) achieved complete remission, and additional RBC transfusions using warmers were completed uneventfully.
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Anemia Hemolítica Autoinmune , Mieloma Múltiple , Reacción a la Transfusión , Humanos , Mieloma Múltiple/complicaciones , Mieloma Múltiple/diagnóstico , Mieloma Múltiple/terapia , Crioglobulinas , Anemia Hemolítica Autoinmune/diagnóstico , Anemia Hemolítica Autoinmune/etiología , Anemia Hemolítica Autoinmune/terapia , Inmunoglobulina ARESUMEN
Myelodysplastic neoplasms (MDS) are a heterogenous clonal disorder of hemopoietic stem cells characterized by cytomorphologic dysplasia, ineffective hematopoiesis, peripheral cytopenias and risk of progression to acute myeloid leukemia (AML). Our understanding of this disease has continued to evolve over the last century. More recently, prognostication and treatment have been determined by cytogenetic and molecular data. Specific genetic abnormalities, such as deletion of the long arm of chromosome 5 (del(5q)), TP53 inactivation and SF3B1 mutation, are increasingly associated with disease phenotype and outcome, as reflected in the recently updated fifth edition of the World Health Organization Classification of Hematolymphoid Tumors (WHO5) and the International Consensus Classification 2022 (ICC 2022) classification systems. Treatment of lower-risk MDS is primarily symptom directed to ameliorate cytopenias. Higher-risk disease warrants disease-directed therapy at diagnosis; however, the only possible cure is an allogenic bone marrow transplant. Novel treatments aimed at rational molecular and cellular pathway targets have yielded a number of candidate drugs over recent years; however few new approvals have been granted. With ongoing research, we hope to increasingly offer our MDS patients tailored therapeutic approaches, ultimately decreasing morbidity and mortality.
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Síndromes Mielodisplásicos , Humanos , Síndromes Mielodisplásicos/terapia , Síndromes Mielodisplásicos/genéticaRESUMEN
Standard treatment regimens for the management of patients with refractory splenic marginal zone lymphoma (SMZL) are currently unavailable. Here, we report a case of SMZL, which, after failing multiple therapeutics, demonstrated an impressive clinical response to combined Venetoclax and Velcade (V2), a treatment combination currently being investigated in the setting of refractory multiple myeloma. We also report a unique histopathology and mutational profile that may have important implications for the characterization and prognosis of SMZL.
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Leucemia Linfocítica Crónica de Células B , Linfoma , Neoplasias del Bazo , Bortezomib/uso terapéutico , Compuestos Bicíclicos Heterocíclicos con Puentes , Humanos , Neoplasias del Bazo/tratamiento farmacológico , Neoplasias del Bazo/patología , SulfonamidasRESUMEN
Although acute lymphoblastic leukemia (ALL) and monoclonal B cell lymphocytosis (MBL) are common neoplasia, a simultaneous presentation is very unusual. Here, we present two different B cell clones, MBL and B-ALL, cocirculating in a 78-year-old African American male. Detailed molecular characterization revealed an unusual MPL (T487I) point mutation and unmutated VH4-39. After nonstandard chemotherapy, the patient remains in morphologic remission. These findings may stimulate further research to clarify the pathogenesis of hematologic neoplasms.
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Acute chest syndrome (ACS) is a common complication and reason for hospital admission in patients with sickle cell disease (SCD). It is also the most common cause of death in this patient population. Most of the time, the trigger for ACS in an individual patient cannot be identified. However, although infection is the most common identifiable cause for ACS, other important triggers are vaso-occlusive crisis (VOC) and asthma. This comprehensive review will focus on the pathogenesis, clinical characteristics, complications and treatment available to manage ACS. But importantly, this review will highlight new possible etiologies, with the goal of improving oxygenation and, therefore, a reduction in sickling and lung damage in this patient population.
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Síndrome Torácico Agudo/etiología , Anemia de Células Falciformes/complicaciones , Síndrome Torácico Agudo/prevención & control , Síndrome Torácico Agudo/terapia , Arteriopatías Oclusivas/complicaciones , Asma/complicaciones , Humanos , OxígenoRESUMEN
Breast cancer is becoming increasingly prevalent in the women greater than 65 years of age. Most tumors are hormone receptor-positive in this group. Breast cancer screening recommendations for older women should be tailored based on life expectancy. Early stage breast cancer should be treated with conservative surgery followed by adjuvant endocrine therapy in HR+ patients. Primary endocrine therapy is a low-risk option for those with limited life expectancy. Adjuvant radiation therapy can be avoided in early stage, low-risk cancers. Evaluation should include comprehensive geriatric assessment. Treatment with less cytotoxic chemotherapy, HER-2 targeted therapies, and other biomarker-driven, molecularly targeted therapies should be sought whenever possible.
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Neoplasias de la Mama , Anciano , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/terapia , Quimioterapia Adyuvante , Terapia Combinada , Detección Precoz del Cáncer , Femenino , HumanosRESUMEN
Splenic diffuse red pulp small B-cell lymphoma (SDRPL) is a rare disease, representing <1% of all non-Hodgkin lymphomas (NHL). The most common clinical manifestations include splenomegaly, lymphocytosis, and hemocytopenia. A diagnosis of SDRPL can be challenging, as it shares multiple clinical and laboratory features with splenic marginal zone lymphoma (SMZL), hairy cell leukemia (HCL), and HCL variant (HCL-v). Obtaining splenic tissue remains the gold standard for diagnosis. In the cases where splenic tissue is not available, diagnosis can be established by a review of peripheral blood and bone marrow studies. SDRPL is characterized by a diffuse involvement of the splenic red pulp by monomorphous small-to-medium sized mature B lymphocytes effacing the white pulp. The characteristic immunophenotype is positive for CD20, DBA.44 (20 to 90%), and IgG, and typically negative for CD5, CD10, CD23, cyclin D1, CD43, annexin A1, CD11c, CD25, CD123, and CD138. The Ki-67 proliferative index is characteristically low. Cyclin D3 is expressed in the majority of SDRPL in contrast with other types of small B-cell lymphomas, thus facilitating the recognition of this disease. There is no standard treatment regimen for SDRPL. Initial treatment options include splenectomy, rituximab monotherapy, or a combination of both. Chemoimmunotherapy should be considered in patients with advanced disease at baseline or progression.
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Leucemia de Células Pilosas , Leucemia Linfocítica Crónica de Células B , Linfoma de Células B , Neoplasias del Bazo , Humanos , Inmunofenotipificación , Leucemia de Células Pilosas/diagnóstico , Leucemia de Células Pilosas/metabolismo , Leucemia de Células Pilosas/terapia , Linfoma de Células B/diagnóstico , Linfoma de Células B/patología , Linfoma de Células B/terapia , Neoplasias del Bazo/diagnóstico , Neoplasias del Bazo/genética , Neoplasias del Bazo/terapiaRESUMEN
BACKGROUND: Male breast cancer (MBC) comprises <1% of all cancers and continues to rise. Because of rarity, there is paucity in the literature; therefore, management of MBC is generalized from female breast cancer (FBC). METHODS: Data from 152 VA Medical Centers were used to analyze the database of Veteran patient with breast cancer diagnosed between 1998 and 2016 using biostatistical software (SAS 9.3). Our primary objective is to compare patient's demographics, breast cancer characteristics, and outcomes for male and female Veterans. FINDING: In total, 8864 patients' records were reviewed;1528 MBC were compared with 7336 FBC with a mean follow up time of 5.5 years (SD 4.17). The mean age at diagnosis was 68.6 years and 57.3 years for MBC and FBC, respectively (P < .0001). Higher numbers of MBC patients (95%) were >50 years of age compared to FBC patients (72%). More MBC patients (16.8 vs. 9.1% and 9 vs. 4%) presented with higher disease stage (III and IV, respectively). Estrogen receptor-positive tumors were more common in MBC (59 versus 52%). Hormonal treatment was received by 27% of MBC versus 19% FBC; chemotherapy 21.3% versus 41.5% and radiation 23.5% versus 60.9%. Forty-two percent MBC and 20% FBC Veterans died during study. Male patients had higher death rate 1.285 (95% CI: 1.150, 1.434, P < .0001) compared to females after adjusting data for age, race, stage, and grade. INTERPRETATION: To the best of our knowledge, this is the largest comparison series of MBC and FBC to date in the Veterans population. The higher mortality rate in MBC patients may be due to late presentation, higher stage at the time of diagnosis and/or tumor biology. Veteran's exposures to hazardous materials during their military deployments as an additional factor for worse prognosis need further investigation.
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Neoplasias de la Mama Masculina/epidemiología , Neoplasias de la Mama Masculina/patología , Disparidades en el Estado de Salud , Veteranos/estadística & datos numéricos , Distribución por Edad , Factores de Edad , Anciano , Neoplasias de la Mama Masculina/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Factores Sexuales , Análisis de Supervivencia , Tasa de Supervivencia , Estados UnidosRESUMEN
Hematological malignancies with a BCR-JAK2 rearrangement have been described only sporadically in the literature over the last three decades. Although most patients suffer from a chronic myeloid neoplasm with marked eosinophilia, the clinical presentation varies significantly and can even manifest as a lymphoid malignancy. In this case report, we present a patient with a therapy-related BCR-JAK2 + myeloid neoplasm with extensive extramedullary disease localizing in the lymph nodes. While treatment with a JAK2 inhibitor (ruxolitinib) was not able to stop disease progression, combination treatment with inhibitors of both JAK2 and BCL2 (venetoclax) resulted in disease control for over 1.5 years. Combining these two inhibitors might be strategic in these patients, not only because BCL2 is a downstream target of JAK/STAT signaling but also because BCL2 is crucial for JAK2 inhibitor resistance. The recent inclusion of JAK2-rearranged malignancies in major classification systems and guidelines emphasizes the importance of not only getting a better understanding of the clinical phenotype of these rare disorders but also of identifying alternative treatment options for patients ineligible for allogeneic stem cell transplantation. Considering the low toxicity of combination treatment with these two small molecule inhibitors, this regimen could be further explored in future studies.
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BACKGROUND: Within the US Department of Veterans Affairs (VA), breast cancer prevalence has more than tripled from 1995 to 2012. Women veterans may be at an increased breast cancer risk based on service-related exposures and posttraumatic stress disorder (PTSD). METHODS: Women veterans aged ≥ 35 years with no personal history of breast cancer were enrolled at 2 urban VA medical centers. We surveyed women veterans for 5-year and lifetime risks of invasive breast cancer using the Gail Breast Cancer Risk Assessment Tool (BCRAT). Data regarding demographics, PTSD status, eligibility for chemoprevention, and genetic counseling were also collected. Descriptive statistics were used to determine results. RESULTS: A total of 99 women veterans participated, of which 60% were Black. In total, 35% were high risk with a 5-year BCRAT > 1.66%. Breast biopsies had been performed in 22% of our entire population; 57% had a family history positive for breast cancer. Comparatively, in our high-risk Black population, 33% had breast biopsies and 94% had a family history. High-risk patients were referred for chemoprevention; 5 accepted and 13 were referred for genetic counseling. PTSD was present in 31% of the high-risk subgroup. CONCLUSIONS: A high percentage of Black patients participated in this pilot study, which also showed an above average rate of PTSD among women veterans who are at high risk for developing breast cancer. Historically, breast cancer rates among Black women are lower than those found in the general population. High participation among Black women veterans in this pilot study uncovered the potential for further study of this population, which is otherwise underrepresented in research. Limitations included a small sample size, exclusively urban population, and self-selection for screening. Future directions include the evaluation of genetic and molecular mutations in high risk Black women veterans, possibly even a role for PTSD epigenetic changes.
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INTRODUCTION: Breast cancer is the most common cancer diagnosed among women and the second most common cause of cancer death among women. There are ways to reduce a woman's risk of breast cancer; however, most eligible women in the United States are neither offered personalized screening nor chemoprevention. Surveys have found that primary care providers are largely unaware of breast cancer risk assessment models or chemoprevention. This survey aims to investigate Veterans Health Administration primary care providers' comfort level, practice patterns, and knowledge of breast cancer risk assessment and chemoprevention. MATERIALS AND METHODS: An online, Research Electronic Data Capture-generated survey was distributed to VHA providers in internal medicine, family medicine, and obstetrics/gynecology. Survey domains were provider demographics, women's health experience, comfort level, practice patterns, barriers to using risk models and chemoprevention, and knowledge of chemoprevention. RESULTS: Of the 167 respondents, 33.1% used the Gail model monthly or more often and only 2.4% prescribed chemoprevention in the past 2 years. Most VHA primary care providers did not answer chemoprevention knowledge questions correctly. Designated women's health providers were more comfortable with risk assessment (P < 0.018) and chemoprevention (P < 0.011) and used both breast cancer risk models (P < 0.0045) and chemoprevention more often (P < 0.153). Reported barriers to chemoprevention were lack of education and provider time. CONCLUSIONS: VHA providers and women Veterans would benefit from a system to ensure that women at increased risk of breast cancer are identified with risk modeling and that risk reduction options, such as chemoprevention, are offered when appropriate. VHA providers requested risk reduction education, which could improve primary care provider comfort level with chemoprevention.
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Neoplasias de la Mama , Quimioprevención , Veteranos , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/prevención & control , Femenino , Humanos , Atención Primaria de Salud , Medición de Riesgo , Estados Unidos , United States Department of Veterans AffairsRESUMEN
Nucleoside diphosphate kinases (Ndks) play an important role in a plethora of regulatory and metabolic functions. Inhibition of the B. anthracis Ndk mRNA results in the formation of nonviable aberrant spores. We report the characterization and crystal structure of the enzyme from B. anthracis nucleoside diphosphate kinase (BaNdk), the first from sporulating bacteria. The enzyme, although from a mesophilic source, is active at extremes of pH (3.5-10.5), temperature (10-95 degrees C) and ionic strength (0.25-4.0M NaCl). It exists as a hexamer that is composed of two SDS-stable trimers interacting in a back-to-back association; mutational analysis confirms that the enzyme is a histidine kinase. The high-resolution crystal structure reported here reveals an unanticipated change in the conformation of residues between 43 and 63 that also regulates substrate entry in other Ndks. A comparative structural analysis involving Ndks from seven mesophiles and three thermophiles has resulted in the delineation of the structure into relatively rigid and flexible regions. The analysis suggests that the larger number of intramolecular hydrogen bonds and to a lesser extent ionic interactions in BaNdk contributes to its high thermostability. Mutational analysis and Molecular Dynamics simulations were used to probe the role of a highly conserved Gly19 (present at the oligomeric interface in most of the Ndks). The results suggest that the mutation leads to a rigidification of those residues that facilitate substrate entry and consequently leads to a large reduction in the kinase activity. Overall, the enzyme characterization helps to understand its apparent adaptation to perform under stress conditions.
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Bacillus anthracis/enzimología , Nucleósido-Difosfato Quinasa/química , Secuencia de Aminoácidos , Bacillus anthracis/metabolismo , Cristalografía por Rayos X , Concentración de Iones de Hidrógeno , Modelos Moleculares , Datos de Secuencia Molecular , Nucleósido-Difosfato Quinasa/metabolismo , Conformación Proteica , Alineación de Secuencia , TemperaturaRESUMEN
The propensity of bacterium to sporulate or retain the vegetative form depends on the amount of phosphorylated Spo0A (Spo0A(-P)), regulated by Spo0E multigene family of phosphatases (Spo0E, YisI and YnzD). Phylogenetic analysis revealed that Spo0E multigene family of phosphatases (SMFP) descends in two distinct clades of aerobic (Bacillus cluster) and anaerobic (Clostridia cluster) sporulating bacteria. High sequence conservation within species gives a notion that these members could have evolved through lineage and species-specific duplication event. Of the five genes in Bacillus cereus group, three are pathogen specific, and their synteny suggests that these paralogs could be involved in the regulation of amino acid metabolism and its transport. Overexpression of B. subtilis Spo0E, an ortholog of SMFP members in B. anthracis (BAS1251), resulted in sporulation deficient phenotype in B. anthracis. B. anthracis Spo0A(-P) binds to a consensus DNA sequence 5'-TGNCGAA-3' ('0A-like box') and loses its DNA binding ability following treatment with B. subtilis Spo0E. Thus, B. subtilis Spo0E acts on B. anthracis Spo0A(-P) and, therefore could complement the function of BAS1251. Further, since '0A-like box' are present in the promoter region of abrB gene, a known regulator of anthrax toxin gene expression, cross talk among SMFP members and Spo0A(-P)-AbrB could regulate the expression of anthrax toxin genes.