Can resistance prehabilitation training bring additional benefits in valvular cardiac surgery? protocol for a randomized controlled trial.

INTRODUCTION: Cardiovascular diseases (CVD) are a group of illnesses that include coronary heart disease, cerebrovascular disease, congenital heart disease and deep vein thrombosis. Major surgery is often chosen as the treatment of choice for CVD. The concept of fast-track rehabilitation after surgery appeared in the 1970s. Participation in these exercise-based prehabilitation programmes may decrease postoperative complications and length of hospital stay. The primary aim of the present study is to evaluate whether the implementation of an additional resistance training (RT) prehabilitation protocol within cardiac exercises based prehabilitation can reduce intensive care unit (ICU) length of stay, postoperative complications and hospital length of stay (LOS). METHODS: A protocol of a prospective, parallel, randomised clinical trial includes 96 adult patients diagnosed with valvular pathology and who have been scheduled for surgery. The participants will be randomly assigned to two groups of 48. Control group will be treated with ventilatory and strengthening of respiratory muscles, and aerobic exercise. Experimental group, in addition, will be treated with RT of peripheral muscles. Both hospital stay and ICU stay will be assessed as main variables. Other secondary variables such as exercise capacity, quality of life and respiratory values will also be assessed. Quantitative variables will be analysed with a T-Test or ANOVA, or Mann Witney if the distribution is non-parametric. RESULTS AND CONCLUSION: This will be the first controlled clinical study focused on adding strength exercise as an additional treatment during prehabilitation. The results of this study will focus on helping to improve rehabilitation and prehabilitation protocols, considering that it is essential to maintain pulmonary training, as well as the inclusion of peripheral exercises that help people with heart disease to be in a better physical condition in order to increase their participation and sense of quality of life.

Frecuencia de toxoplasmosis y su relación con el diagnóstico clínico de pacientes que asistieron al Instituto SELADIS entre enero 2021 y julio 2022 / Frequency of toxoplasmosis and its relationship with the clinical diagnosis of patients attending the SELADIS Institute between January 2021 and July 2022

Introducción . La toxoplasmosis es una zoonosis parasitaria que compromete al ser humano y muchas otras especies de vertebrados, provocada por el agente etiológico Toxoplasma gondii. Objetivo . El objetivo del presente estudio es determinar la frecuencia de toxoplasmosis en muestras de pacientes atendidos en el Instituto SELADIS (*) durante el período de enero de 2021 a julio de 2022, además de su relación con el diagnóstico clínico que incluyen las solicitudes de pruebas. Materiales y métodos . Se consideraron 290 pruebas de pacientes con requerimiento de anticuerpos IgG e IgM anti-Toxoplasma gondii, utilizando la prueba de ELISA (comercial). Resultados . Se encontró que la frecuencia de anticuerpos IgM contra T. gondii fue del 7.24 % (21/290) y de anticuerpos IgG contra T. gondii, del 33.1 % (96/290). En relación con la edad, se observó que en pacientes adultos (mayores de 31 años) la frecuencia fue mayor (IgM: 4.14% % e IgG: 23.8%). El 6.9% de los pacientes tenían un diagnóstico relacionado con patología ocular, el 6.21% eran mujeres embarazadas y entre ellas la seropositividad para anticuerpos IgG fue del 24.64%; y para IgM fue del 8.70% (primer trimestre 2.90% y segundo 4.35%). La seropositividad para anticuerpos IgG, en pacientes trasplantados renales, fue del 1.4% y para IgM del 0%. En pacientes con adenomegalia, el 2.4% fueron positivos para IgG y el 0.69% para IgM. Conclusión . En conclusión, se encontró que la frecuencia de anticuerpos contra toxoplasmosis en la población de estudio fue de 33.1% para IgG y 7.24% para IgM. En relación con el diagnóstico clínico, se encontró que los tres principales escenarios de salud son (en orden descendente de importancia) para el Ac IgG contra toxoplasmosis: patología ocular, el embarazo y adenomegalias. En cambio, la relación con el diagnóstico de estos tres escenarios para el Ac IgM contra toxoplasmosis, son: el embarazo, patología ocular y adenomegalias.

Introduction . Toxoplasmosis is a parasitic zoonosis disease that affects humans and many other vertebrate species, and is caused by the etiological agent known as Toxoplasma gondii. Objective . The aim of this study is to determine the frequency of toxoplasmosis in samples from patients who were assisted in the SELADIS Institute (*) in the period between January 2021 and July 2022, in addition to its relation to the clinical diagnosis including requested tests. Materials and methods . 290 samples from patients were considered that also required IgG and IgM anti-Toxoplasma gondii antibodies, using an ELISA assay (commercial kit). Results. The frequency of IgM antibodies against T. gondii was 7.24% (21/290) and IgG antibodies against T. gondii were 33.1% (96/290). In relation to age, it was observed that in adult patients (over 31 years of age) the frequency was higher (IgM: 4.14%, IgG: 23.8%). 6.9% of the patients had a diagnosis related to ocular pathology, 6.21% were pregnant women and among them the seropositivity for IgG antibodies was 24.64%; and for IgM it was 8.70% (first trimester 2.90% and second 4.35%). The seropositivity for IgG antibodies in kidney transplant patients was 1.4% and 0% for IgM. In patients with adenomegaly, 2.4% were positive for IgG and 0.69% for IgM. Conclusion . In conclusion, it was found that the frequency of antibodies against Toxoplasmosis in the study population was 33.1% for IgG and 7.24% for IgM. In relation to clinical diagnosis, it was found that the three main health scenarios are (in descending order of importance), for IgG Ab against toxoplasmosis: ocular pathology, pregnancy and adenomegaly. Besides this, it was found that the relation of these three scenarios diagnoses to IgM Ab against toxoplasmosis are: pregnancy, ocular pathology and adenomegaly.

Impact of the COVID pandemic on vascular access creation for haemodialysis in 16 Spanish haemodialysis centres.

Background: The coronavirus disease (COVID) pandemic has resulted in a major disruption in healthcare that has affected several medical and surgical specialties. European and American Vascular Societies have proposed deferring the creation of an elective vascular access (VA) [autologous or prosthetic arteriovenous fistula (AVF) or arteriovenous graft (AVG)] in incident patients on haemodialysis (HD) in the era of the COVID pandemic. The aim of this study is to examine the impact of the COVID pandemic on VA creation and the central venous catheter (CVC)-related hospitalizations and complications in HD patients dialyzed in 16 Spanish HD units of three different regions. Methods: We compared retrospectively two periods of time: the pre-COVID (1 January 2019-11 March 2020) and the COVID era (12 March 2020-30 June 2021) in all HD patients (prevalent and incident) dialyzed in our 16 HD centres. The variables analysed were type of VA (CVC, AVF and AVG) created, percentage of CVC in incident and prevalent HD patients, CVC-related hospitalizations and complications (infection, extrusion, disfunction, catheter removal) and percentage of CVC HD sessions that did not reach the goal of Kt (>45) as a marker of HD adequacy. Results: A total of 1791 VAs for HD were created and 905 patients started HD during the study period. Patients who underwent vascular access surgery during the COVID period compared with pre-COVID period were significantly younger, with a significant decrease in surgical activity to create AVFs and AVGs in older HD patients (>75 and >85 years of age). There was a significant increase in CVC placement (from 59.7% to 69.5%; P < 0.001) from the pre-COVID to the COVID period. During the COVID pandemic, a significantly higher number of patients started HD through a CVC (80.3% versus 69.1%; P < 0.001). The percentage of CVC in prevalent HD patients has not decreased in the 19 months since the start of the pandemic [414 CVC/1058 prevalent patients (39.4%)]. No significant changes were detected in CVC-related hospitalizations between the pre-COVID and COVID periods. In the COVID period, a significant increase in catheter replacement and the percentage of HD session that did not reach the HD dose objective (Kt > 45) was observed. Conclusions: COVID has presented a public health system crisis that has influenced VA for HD, with an increase in CVCs relative to AVFs. A decrease in HD sessions that did not reach the HD dose objective was observed in the COVID period compared with a pre-COVID period.

Frecuencia y distribución de enteroparásitos en área rural del departamento de La Paz / Frequency and distribution of enteroparasites in rural area in La Paz

INTRODUCCIÓN: las enfermedades parasitarias representan un problema de salud pública debido a su alta prevalencia por todo el mundo sobre todo en países en desarrollo, especialmente en áreas rurales y Bolivia no es la excepción. OBJETIVO: el presente estudio tuvo el objetivo de determinar la frecuencia y distribución de enteroparásitos en 8 municipios rurales del departamento de La Paz durante el periodo de agosto a septiembre de 2014. MATERIALES Y MÉTODOS: el trabajo es un estudio tipo transversal-descriptivo con un universo de trabajo de 1238 muestras de heces fecales conservadas con formol, las cuales fueron enviadas por el equipo médico de SUYANA (organización no gubernamental sin fines de lucro) a los laboratorios del Instituto SELADIS (Servicios de Laboratorio de Diagnóstico e Investigación en Salud). RESULTADOS: se realizaron estudios coproparasitológicos directos de cada una de las muestras y la observación microscópica dio los siguientes resultados. Se evidencio la presencia de enteroparásitos en 89,5% de la población estudiada, de los cuales 97,2% representan protozoarios tales como B. hominis, E. coli (protoozoos comensales) y G. lamblia (protozoo intestinal patógeno) los cuales estarían como los de mayor distribución, por otro lado el 2.8% de la población total corresponden a helmintos donde H. nana tiene una distribución de 1,8%, A. lumbricoides 0,7% y T. trichiura, S. stercoralis, Uncinarias estarían en el 0,1% de la población. También se pudo evidenciar que la mayor distribución de enteroparásitos estaría entre 1-10 años de edad (37,4%). Finalmente se evidencio que de las 8 poblaciones de estudio Charazani, Calacoto, Comanche presentarían mayor distribución de enteroparásitos (10-11 parásitos). CONCLUSIÓN: se evidencio que casi el 90% de la población en estudio, presentarían parásitos intestinales, con un claro predominio de los protozoarios sobre los helmintos. Esta información epidemiológica servirá de apoyo para mejorar los programas de salud en estas poblaciones.

INTRODUCTION: parasitic diseases represent a public health problem because of its high prevalence throughout the world, especially in developing countries, particularly in rural areas and Bolivia is no exception. OBJETIVE: therefore, the present study had the objective of determining the frequency and distribution of enteroparasites in eight municipalities of La Paz between August and September in 2014. MATERIALS AND METHODS: this was a cross-sectional-descriptive study with a universe of 1238 formalin-preserved stool samples, which were sent for analysis by the medical team of SUYANA (a non-profi t organization) to the Bolivian Institute of Health Diagnostic and Research Laboratory Services (SELADIS, acronym in Spanish). RESULTS: Copro-parasitological studies of each sample and microscopic analysis were detected. As a result, prevalence of infection by any given enteroparasites were detected, 89.5% of protozoans (B. hominis, E. coli (commensal protozoa) and 97.2%, G. lamblia (pathogenic intestinal protozoa) which represent the highest distribution. Besides, we identified, 2.8% of helmintos, among them, 1.8% of H. nana, 1.7% of A. lumbricoides and 0.1% of others (T. trichiura, S. stercoralis and Uncinarias). According to age group, 37.4% were people between 1 and 10 years old (enteroparasites infection). From eight municipalities, Charazani, Calacoto, and Comanche had the highest distribution of enteparasites (10-11 parasites). CONCLUSIONS: the present study showed that 90% of the population had intestinal parasites, where protozoans were higher than helminths. This epidemiological information could be reliable to improve health care programs for these populations.

Students' Perceptions of Instructional Rubrics in Neurological Physical Therapy and Their Effects on Students' Engagement and Course Satisfaction.

One of the main challenges faced by physical therapy (PT) students is to learn the practical skills involved in neurological physical therapy (PT). To help them to acquire these skills, a set of rubrics were designed for formative purposes. This paper presents the process followed in the creation of these rubrics and their application in the classroom, noting that students perceived them as valid, reliable, and highly useful for learning. The perception of the validity and usefulness of the rubrics has different closely related dimensions, showing homogeneous values across the students´ sociodemographic and educational variables, with the exception of dedication to studying, which showed a significant relationship with schoolwork engagement and course satisfaction. The adequacy of the hypothesized structural model of the relationships among the variables was confirmed. Direct effects of the perception of the rubrics' validity and engagement on course satisfaction were found, as well as direct effects of the assessment of the usefulness of the rubrics on schoolwork engagement and indirect effects on course satisfaction through this latter variable. The results are discussed taking into account the conclusions of previous research and different instructional implications.

Validity of the International Physical Activity Questionnaire Long Form for Assessing Physical Activity and Sedentary Behavior in Subjects with Chronic Stroke.

Validation studies of questionnaires used to assess physical activity (PA) and sedentary behavior (SB) in stroke survivors are scarce. This cross-sectional study aimed to examine the validity of the International Physical Activity Questionnaire long-form (IPAQ-LF) in community living adults with post-stroke sequelae (≥6 months) and preserved ambulation. Participants' functional mobility, lower limb strength, ambulatory level, stroke severity, and disability were assessed. An accelerometer (ActiGraph GT3X+) was worn for ≥7 consecutive days. Subsequently, the IPAQ-LF was interview-administered. Fifty-six participants (58.1 ± 11.1 years, 66.1% male) were included. A strong correlation between the two methods was found for total PA time (ρ = 0.55, p < 0.001). According to the Bland-Altman analyses, over-reporting moderate-to-vigorous PA and under-reporting total PA in the IPAQ-LF were found in those participants with higher PA levels. Both methods measured sedentary time similarly, though random error was observed between them. Moderate-strong correlations were found between the IPAQ-LF and physical function (ρ = 0.29-0.60, p < 0.05). In conclusion, in people with chronic stroke, the IPAQ-LF presented acceptable levels of validity for estimating total PA time in those who are insufficiently active. Therefore, it could be a useful tool to screen for inactive individuals with chronic stroke who can benefit from PA interventions addressed to implement healthier lifestyles.

Mediterranean diet and health: A systematic review of epidemiological studies and intervention trials.

Diet is a crucial variable for a healthy life. A rapidly growing number of studies in recent years support the hypothesis that the Mediterranean diet (MedDiet) has a beneficial effect on certain body systems, but the highly varied objectives and quality of these publications warrants an updated assessment. In the present review we performed a comprehensive evaluation of current evidence on the impact of the MedDiet on human health, assessing its effect on the incidence or progression of the main non-communicable diseases and their intermediate outcomes and risk factors. We scrutinised the clinical evidence from observational studies and randomised controlled trials. Cardiovascular disease was the condition with most information. The MedDiet showed a general preventive effect, which was reproduced to varying degrees for certain intermediate cardiovascular outcomes such as blood pressure, lipids, obesity, metabolic syndrome and diabetes. Benefits were also found for several types of cancer, brain function (including cognition, mood and to a lesser extent Parkinson's disease) and mortality. The quality of the published evidence was, however, generally moderate or low. In conclusion, the MedDiet shows a favourable impact on health. General adoption of a MedDiet is concordant with current policies promoting healthy and sustainable nutrition worldwide. Nonetheless, more high-quality research is needed to improve the consistency of the findings.

The Mediterranean diet: A historical perspective on food for health.

The Mediterranean diet (MedDiet) represents the crystallisation of the centuries-old cooking legacies of different civilisations. The association of the MedDiet with longevity and low cardiovascular risk prompted the Seven Countries Study, which provided epidemiological evidence on the health effects of diet. This led to further studies, both epidemiological and interventional. Scales to measure adherence as well as studies of food components have consolidated a body of knowledge that is of great interest to institutions and governmental agencies. The recognition of its benefits for health has made the widespread introduction of the MedDiet an urgent challenge. Parallel efforts are being made to extend research through experimental and clinical studies. The purpose of this review is to present the historical background of the MedDiet, the main steps leading to the recognition of its health benefits, and the current strategy to facilitate its global implementation.

Cross-sectional study of quadriceps properties and postural stability in patients with chronic stroke and limited vs. non-limited community ambulation.

Background: Changes in the paretic-side metabolism post-stroke and quadriceps muscle mechanical properties favour muscle wasting, affecting postural instability and walking impairment. Further clarification is needed in subjects post-stroke who show limited or non-limited community ambulation. Objectives: To analyze between-limb differences in quadriceps muscle thickness, strength and thigh cutaneous temperature, as well as investigate postural stability in subjects with chronic stroke and limited vs. non-limited community ambulation and compared against healthy controls. Methods: In this controlled cross-sectional study, 26 participants with chronic hemiparesis post-stroke (divided in a slow gait group (SG<0.8 m/s) (n = 13) and a fast gait group with full community ambulation speed (FG≥0.8 m/s)) and 18 healthy people were recruited. Thigh surface temperature, rectus femoris (RF) and vastus intermedius (VI) muscles thickness, quadriceps' isometric maximal voluntary contraction and postural stability were measured. Results: The SG presented significantly lower RF (P = .019) and VI (P = .006) muscle thickness, less peak force (P < .001) and lower temperature (P = .002) in the paretic vs the non-paretic limb. The FG showed significantly lower VI thickness (P = .036) and peak force (P < .001) in the paretic vs the non-paretic limb. Regarding balance, all indices were worse in the SG versus the FG and CG. Conclusions: Subjects of the FG, despite showing full community ambulation speed, had less quadriceps strength and VI muscle thickness but not RF muscle wasting in the paretic limb. The paretic VI muscle wasting may be an important factor to reach normal walking. The SG showed between-limb differences in all the studied variables and the worst postural stability.

Maturation-associated gene expression profiles during normal human bone marrow erythropoiesis.

Erythropoiesis has been extensively studied using in vitro and in vivo animal models. Despite this, there is still limited data about the gene expression profiles (GEP) of primary (ex vivo) normal human bone marrow (BM) erythroid maturation. We investigated the GEP of nucleated red blood cell (NRBC) precursors during normal human BM erythropoiesis. Three maturation-associated populations of NRBC were identified and purified from (fresh) normal human BM by flow cytometry and the GEP of each purified cell population directly analyzed using DNA-oligonucleotide microarrays. Overall, 6569 genes (19% of the genes investigated) were expressed in ≥1 stage of BM erythropoiesis at stable (e.g., genes involved in DNA process, cell signaling, protein organization and hemoglobin production) or variable amounts (e.g., genes related to cell differentiation, apoptosis, metabolism), the latter showing a tendency to either decrease from stage 1 to 3 (genes associated with regulation of erythroid differentiation and survival, e.g., SPI1, STAT5A) or increase from stage 2 to stage 3 (genes associated with autophagy, erythroid functions such as heme production, e.g., ALAS1, ALAS2), iron metabolism (e.g., ISCA1, SLC11A2), protection from oxidative stress (e.g., UCP2, PARK7), and NRBC enucleation (e.g., ID2, RB1). Interestingly, genes involved in apoptosis (e.g., CASP8, P2RX1) and immune response (e.g., FOXO3, TRAF6) were also upregulated in the last stage (stage 3) of maturation of NRBC precursors. Our results confirm and extend on previous observations and providing a frame of reference for better understanding the critical steps of human erythroid maturation and its potential alteration in patients with different clonal and non-clonal erythropoietic disorders.

Maturation-associated gene expression profiles along normal human bone marrow monopoiesis.

Human monopoiesis is a tightly coordinated process which starts in the bone marrow (BM) haematopoietic stem cell (HSC) compartment and leads to the production of circulating blood mature monocytes. Although mature monocytes/macrophages have been extensively studied in both normal or inflammatory conditions, monopoiesis has only been assessed in vitro and in vivo animal models, due to low frequency of the monocytic precursors in the normal human BM. Here we investigated the transcriptional profile along normal human BM monopoiesis. Five distinct maturation-associated stages of monocytic precursors were identified and isolated from (fresh) normal human BM through fluorescence-activated cell sorting, and the gene expression profile (GEP) of each monocytic precursor subset was analysed by DNA-oligonucleotide microarrays. Overall, >6000 genes (18% of the genes investigated) were expressed in ≥1 stage of BM monopoiesis at stable or variable amounts, showing early decrease in cell proliferation with increased levels of expression of genes linked with cell differentiation. The here-defined GEP of normal human BM monopoiesis might contribute to better understand monocytic differentiation and the identification of novel monocytic candidate markers, while also providing a frame of reference for the study of monocytic maturation in both neoplastic and non-neoplastic disease conditions involving monocytic precursor cells.

Phenotypic, transcriptomic, and genomic features of clonal plasma cells in light-chain amyloidosis.

Immunoglobulin light-chain amyloidosis (AL) and multiple myeloma (MM) are 2 distinct monoclonal gammopathies that involve the same cellular compartment: clonal plasma cells (PCs). Despite the fact that knowledge about MM PC biology has significantly increased in the last decade, the same does not apply for AL. Here, we used an integrative phenotypic, molecular, and genomic approach to study clonal PCs from 24 newly diagnosed patients with AL. Through principal-component-analysis, we demonstrated highly overlapping phenotypic profiles between AL and both monoclonal gammopathy of undetermined significance and MM PCs. However, in contrast to MM, highly purified fluorescence-activated cell-sorted clonal PCs from AL (n = 9) showed almost normal transcriptome, with only 38 deregulated genes vs normal PCs; these included a few tumor-suppressor (CDH1, RCAN) and proapoptotic (GLIPR1, FAS) genes. Notwithstanding, clonal PCs in AL (n = 11) were genomically unstable, with a median of 9 copy number alterations (CNAs) per case, many of such CNAs being similar to those found in MM. Whole-exome sequencing (WES) performed in 5 AL patients revealed a median of 15 nonrecurrent mutations per case. Altogether, our results show that in the absence of a unifying mutation by WES, clonal PCs in AL display phenotypic and CNA profiles similar to MM, but their transcriptome is remarkably similar to that of normal PCs.

Phenotypic and genomic analysis of multiple myeloma minimal residual disease tumor cells: a new model to understand chemoresistance.

Persistence of chemoresistant minimal residual disease (MRD) plasma cells (PCs) is associated with inferior survival in multiple myeloma (MM). Thus, characterization of the minor MRD subclone may represent a unique model to understand chemoresistance, but to our knowledge, the phenotypic and genetic features of the MRD subclone have never been investigated. Here, we compared the antigenic profile of MRD vs diagnostic clonal PCs in 40 elderly MM patients enrolled in the GEM2010MAS65 study and showed that the MRD subclone is enriched in cells overexpressing integrins (CD11a/CD11c/CD29/CD49d/CD49e), chemokine receptors (CXCR4), and adhesion molecules (CD44/CD54). Genetic profiling of MRD vs diagnostic PCs was performed in 12 patients; 3 of them showed identical copy number alterations (CNAs), in another 3 cases, MRD clonal PCs displayed all genetic alterations detected at diagnosis plus additional CNAs that emerged at the MRD stage, whereas in the remaining 6 patients, there were CNAs present at diagnosis that were undetectable in MRD clonal PCs, but also a selected number of genetic alterations that became apparent only at the MRD stage. The MRD subclone showed significant downregulation of genes related to protein processing in endoplasmic reticulum, as well as novel deregulated genes such as ALCAM that is prognostically relevant in MM and may identify chemoresistant PCs in vitro. Altogether, our results suggest that therapy-induced clonal selection could be already present at the MRD stage, where chemoresistant PCs show a singular phenotypic signature that may result from the persistence of clones with different genetic and gene expression profiles. This trial was registered atwww.clinicaltrials.gov as #NCT01237249.

Phenotypic profile of expanded NK cells in chronic lymphoproliferative disorders: a surrogate marker for NK-cell clonality.

Currently, the lack of a universal and specific marker of clonality hampers the diagnosis and classification of chronic expansions of natural killer (NK) cells. Here we investigated the utility of flow cytometric detection of aberrant/altered NK-cell phenotypes as a surrogate marker for clonality, in the diagnostic work-up of chronic lymphoproliferative disorders of NK cells (CLPD-NK). For this purpose, a large panel of markers was evaluated by multiparametric flow cytometry on peripheral blood (PB) CD56(low) NK cells from 60 patients, including 23 subjects with predefined clonal (n = 9) and polyclonal (n = 14) CD56(low) NK-cell expansions, and 37 with CLPD-NK of undetermined clonality; also, PB samples from 10 healthy adults were included. Clonality was established using the human androgen receptor (HUMARA) assay. Clonal NK cells were found to show decreased expression of CD7, CD11b and CD38, and higher CD2, CD94 and HLADR levels vs. normal NK cells, together with a restricted repertoire of expression of the CD158a, CD158b and CD161 killer-associated receptors. In turn, NK cells from both clonal and polyclonal CLPD-NK showed similar/overlapping phenotypic profiles, except for high and more homogeneous expression of CD94 and HLADR, which was restricted to clonal CLPD-NK. We conclude that the CD94(hi)/HLADR+ phenotypic profile proved to be a useful surrogate marker for NK-cell clonality.

Ex vivo identification and characterization of a population of CD13(high) CD105(+) CD45(-) mesenchymal stem cells in human bone marrow.

INTRODUCTION: Mesenchymal stem cells (MSCs) are multipotent cells capable of self-renewal and multilineage differentiation. Their multipotential capacity and immunomodulatory properties have led to an increasing interest in their biological properties and therapeutic applications. Currently, the definition of MSCs relies on a combination of phenotypic, morphological and functional characteristics which are typically evaluated upon in vitro expansion, a process that may ultimately lead to modulation of the immunophenotypic, functional and/or genetic features of these cells. Therefore, at present there is great interest in providing markers and phenotypes for direct in vivo and ex vivo identification and isolation of MSCs. METHODS: Multiparameter flow cytometry immunophenotypic studies were performed on 65 bone marrow (BM) samples for characterization of CD13(high) CD105(+) CD45(-) cells. Isolation and expansion of these cells was performed in a subset of samples in parallel to the expansion of MSCs from mononuclear cells following currently established procedures. The protein expression profile of these cells was further assessed on (paired) primary and in vitro expanded BM MSCs, and their adipogenic, chondrogenic and osteogenic differentiation potential was also determined. RESULTS: Our results show that the CD13(high) CD105(+) CD45(-) immunophenotype defines a minor subset of cells that are systematically present ex vivo in normal/reactive BM (n = 65) and that display immunophenotypic features, plastic adherence ability, and osteogenic, adipogenic and chondrogenic differentiation capacities fully compatible with those of MSCs. In addition, we also show that in vitro expansion of these cells modulates their immunophenotypic characteristics, including changes in the expression of markers currently used for the definition of MSCs, such as CD105, CD146 and HLA-DR. CONCLUSIONS: BM MSCs can be identified ex vivo in normal/reactive BM, based on a robust CD13(high) CD105(+) and CD45(-) immunophenotypic profile. Furthermore, in vitro expansion of these cells is associated with significant changes in the immunophenotypic profile of MSCs.

The cellular origin and malignant transformation of Waldenström macroglobulinemia.

Although information about the molecular pathogenesis of Waldenström macroglobulinemia (WM) has significantly advanced, the precise cell of origin and the mechanisms behind WM transformation from immunoglobulin-M (IgM) monoclonal gammopathy of undetermined significance (MGUS) remain undetermined. Here, we undertook an integrative phenotypic, molecular, and genomic approach to study clonal B cells from newly diagnosed patients with IgM MGUS (n = 22), smoldering (n = 16), and symptomatic WM (n = 11). Through principal component analysis of multidimensional flow cytometry data, we demonstrated highly overlapping phenotypic profiles for clonal B cells from IgM MGUS, smoldering, and symptomatic WM patients. Similarly, virtually no genes were significantly deregulated between fluorescence-activated cell sorter-sorted clonal B cells from the 3 disease groups. Interestingly, the transcriptome of the Waldenström B-cell clone was highly different than that of normal CD25(-)CD22(+) B cells, whereas significantly less genes were differentially expressed and specific WM pathways normalized once the transcriptome of the Waldenström B-cell clone was compared with its normal phenotypic (CD25(+)CD22(+low)) B-cell counterpart. The frequency of specific copy number abnormalities [+4, del(6q23.3-6q25.3), +12, and +18q11-18q23] progressively increased from IgM MGUS and smoldering WM vs symptomatic WM (18% vs 20% and 73%, respectively; P = .008), suggesting a multistep transformation of clonal B cells that, albeit benign (ie, IgM MGUS and smoldering WM), already harbor the phenotypic and molecular signatures of the malignant Waldenström clone.

Involvement of primary mesenchymal precursors and hematopoietic bone marrow cells from chronic myeloid leukemia patients by BCR-ABL1 fusion gene.

For decades now, it is well established that chronic myeloid leukemia (CML) is a hematopoietic stem cell(HPC) disorder. However, it remains to be determined whether BCR-ABL1 gene rearrangement occurs in a HPC or at an earlier stem cell and whether the degree of involvement of hematopoiesis by the BCR-ABL1 fusion gene relates to the response to therapy. Here, we have investigated by interphase fluorescence in situ hybridization (iFISH) the distribution of BCR-ABL1 fusion gene in FACS-sorted bone marrow (BM) populations of mesenchymal precursor cells (MPC) and other hematopoietic cell populations from 18 newly diagnosed CML patients. Overall, our results showed systematic involvement at relatively high percentages of BM maturing neutrophils (97%615%), basophils (95%612%), eosinophils (90%68%), CD341 precursors cells (90%67%),monocytes (84%630%), nucleated red blood cells (87%624%), and mast cells (77%633%). By contrast, MPC(30%634%), B-cells (15%627%), T-lymphocytes (50%626%), and NK-cells (35%634%) were involved at lower percentages. In 8/18 CML patients, 2 tumor BCR-ABL11 subclones were detected by iFISH. Of note, all tumor cell subclones were systematically detected in CD341 cells, whereas MPC were only involved by the ancestral tumor cell subclone. In summary, here we confirm the presence at diagnosis of the BCR-ABL1 fusion gene inMPC, CD341 precursors, and other different BM hematopoietic myeloid cell lineages from CML patients,including also in a significant fraction of cases, a smaller percentage of T, B, and NK lymphocytes.Interestingly, involvement of MPC was restricted to the ancestral BCR-ABL11 subclone.

Circulating clonotypic B cells in multiple myeloma and monoclonal gammopathy of undetermined significance.

The B-cell compartment in which multiple myeloma stem cells reside remains unclear. We investigated the potential presence of mature, surface-membrane immunoglobulin-positive B lymphocytes clonally related to the tumor bone marrow plasma cells among different subsets of peripheral blood B cells from ten patients (7 with multiple myeloma and 3 with monoclonal gammopathies of undetermined significance). The presence of clonotypic immunoglobulin heavy chain gene rearrangements was determined in multiple highly-purified fractions of peripheral blood B-lymphocytes including surface-membrane IgM(+) CD27(-) naïve B-lymphocytes, plus surface-membrane IgG(+), IgA(+) and IgM(+) memory CD27(+) B cells, and normal circulating plasma cells, in addition to (mono)clonal plasma cells, by a highly-specific and sensitive allele-specific oligonucleotide polymerase chain reaction directed to the CDR3 sequence of the rearranged IGH gene of tumor plasma cells from individual patients. Our results showed systematic absence of clonotypic rearrangements in all the different B-cell subsets analyzed, including M-component isotype-matched memory B-lymphocytes, at frequencies <0.03 cells/µL (range: 0.0003-0.08 cells/µL); the only exception were the myeloma plasma cells detected and purified from the peripheral blood of four of the seven myeloma patients. These results indicate that circulating B cells from patients with multiple myeloma and monoclonal gammopathies of undetermined significance are usually devoid of clonotypic B cells while the presence of immunophenotypically aberrant myeloma plasma cells in peripheral blood of myeloma patients is a relatively frequent finding.

Detailed characterization of multiple myeloma circulating tumor cells shows unique phenotypic, cytogenetic, functional, and circadian distribution profile.

Circulating myeloma tumor cells (CTCs) as defined by the presence of peripheral blood (PB) clonal plasma cells (PCs) are a powerful prognostic marker in multiple myeloma (MM). However, the biological features of CTCs and their pathophysiological role in MM remains unexplored. Here, we investigate the phenotypic, cytogenetic, and functional characteristics as well as the circadian distribution of CTCs vs paired bone marrow (BM) clonal PCs from MM patients. Our results show that CTCs typically represent a unique subpopulation of all BM clonal PCs, characterized by downregulation (P < .05) of integrins (CD11a/CD11c/CD29/CD49d/CD49e), adhesion (CD33/CD56/CD117/CD138), and activation molecules (CD28/CD38/CD81). Fluorescence in situ hybridization analysis of fluorescence-activated cell sorter-sorted CTCs also unraveled different cytogenetic profiles vs paired BM clonal PCs. Moreover, CTCs were mostly quiescent and associated with higher clonogenic potential when cocultured with BM stromal cells. Most interestingly, CTCs showed a circadian distribution which fluctuates in a similar pattern to that of CD34(+) cells, and opposite to stromal cell-derived factor 1 plasma levels and corresponding surface expression of CXC chemokine receptor 4 on clonal PCs, suggesting that in MM, CTCs may egress to PB to colonize/metastasize other sites in the BM during the patients' resting period.

Gene expression profile of highly purified bone marrow mast cells in systemic mastocytosis.

BACKGROUND: Despite the fact that a great majority (>90%) of patients with systemic mastocytosis (SM) carry a common genetic lesion, the D816V KIT mutation, little is known regarding the molecular and biological pathways underlying the clinical heterogeneity of the disease. OBJECTIVE: We sought to analyze the gene expression profile (GEP) of bone marrow mast cells (BMMCs) in patients with SM and its association with distinct clinical variants of the disease. METHODS: GEP analyses were performed by using DNA-oligonucleotide microarrays in highly purified BMMCs from patients with SM carrying the D816V KIT mutation (n=26) classified according to the diagnostic subtype of SM versus normal/reactive BMMCs (n=7). Validation of GEP results was performed with flow cytometry in the same set of samples and in an independent cohort of 176 subjects. RESULTS: Overall, 758 transcripts were significantly deregulated in patients with SM, with a common GEP (n=398 genes) for all subvariants of SM analyzed. These were characterized by upregulation of genes involved in the innate and inflammatory immune response, including interferon-induced genes and genes involved in cellular responses to viral antigens, together with complement inhibitory molecules and genes involved in lipid metabolism and protein processing. Interestingly, aggressive SM additionally showed deregulation of apoptosis and cell cycle-related genes, whereas patients with indolent SM displayed increased expression of adhesion-related molecules. CONCLUSION: BMMCs from patients with different clinical subtypes of SM display distinct GEPs, which might reflect new targetable pathways involved in the pathogenesis of the disease.