Bioactive Vitamins and Epigenetic Modifications in Diabetes: A Perspective

Diabetes is a complex metabolic disease that has been associated with epigenetic changes. External factors such as dietary patterns can induce an imbalance in the pools of micronutrients and macronutrients in the body. Consequently, bioactive vitamins may influence epigenetic mechanisms via several pathways: involvement in the control of gene expression, and in protein synthesis, by acting as coenzymes and co-factors in the metabolism of methyl groups or methylation of DNA and histones. Herein, we present a perspective on the relevance of bioactive vitamins in the epigenetic modifications that occur in diabetes.

Acute myocardial infarction in myeloproliferative neoplasms

Myeloproliferative neoplasms (MPNs) are a heterogeneous group of hematologic malignancies characterized by an abnormal proliferation of cells of the myeloid lineage. Affected individuals are at increased risk for cardiovascular and thrombotic events. Myocardial infarction (MI) may be one of the earliest clinical manifestations of MPNs or may be a thrombotic complication that develops during the natural course of the disease. In the present review, we examine the epidemiology, pathogenesis, clinical presentation, and management of MI in MPNs based on the available literature. Moreover, we review potential biomarkers that could mediate the MI-MPNs crosstalk, from classical biochemical tests, e.g., lactate dehydrogenase, creatine kinase and troponins, to pro-inflammatory cytokines, oxidative stress markers, and clonal hematopoiesis.

Molecular Aspects of Hematological Malignancies and Benign Hematological Disorders

Hematology represents a dynamic specialty in clinical medicine that requires solid knowledge of normal and pathological hematopoiesis, cytomorphology, pathology, immunology, genetics and molecular biology [...].

Budd-Chiari syndrome in myeloproliferative neoplasms: A review of literature

Myeloproliferative neoplasms (MPNs) are defined as clonal disorders of the hematopoietic stem cell in which an exaggerated production of terminally differentiated myeloid cells occurs. Classical, Philadelphia-negative MPNs, i.e., polycythemia vera, essential thrombocythemia and primary myelofibrosis, exhibit a propensity towards the development of thrombotic complications that can occur in unusual sites, e.g., portal, splanchnic or hepatic veins, the placenta or cerebral sinuses. The pathogenesis of thrombotic events in MPNs is complex and requires an intricate mechanism involving endothelial injury, stasis, elevated leukocyte adhesion, integrins, neutrophil extracellular traps, somatic mutations (e.g., the V617F point mutation in the JAK2 gene), microparticles, circulating endothelial cells, and other factors, to name a few. Herein, we review the available data on Budd-Chiari syndrome in Philadelphia-negative MPNs, with a particular focus on its epidemiology, pathogenesis, histopathology, risk factors, classification, clinical presentation, diagnosis, and management.

Development of a SPE-LC-MS Method for the Quantitation of Palbociclib and Abemaciclib in Human Plasma

Palbociclib and abemaciclib are two cyclin-dependent kinases 4 and 6 used for breast cancer treatment. Levels of these medicines present a significant interindividual variability, so monitoring those concentrations might be necessary in therapy. Most of the methods presented so far in the literature use simple protein precipitation of plasma proteins as sample preparation method followed by direct injection of the supernatant into the LC instrument, preceded or not by a simple filtration step. Within that approach, the probability of injecting proteins in the chromatographic system is increased. With the purpose of obtaining a cleaner extract of the drugs, we developed and validated a simple and accurate LC-MS method for determining palbociclib and abemaciclib in human plasma. Solid phase extraction (SPE) using Oasis PRiME HLB^® cartridges was used for plasma sample preparation. The method provided clean extracts with a recovery extraction higher than 85% for both compounds. Separation was achieved by high-performance liquid chromatography (HPLC), using a C18 (4.6 × 50 mm) column, with a gradient elution of ammonium acetate/acetic acid-acetonitrile as the mobile phase. Detection was performed by mass spectrometry (MS) in single ion recording (SIR) mode. Intra-day and inter-day precision data for both analytes were 3.8-7.2% and 3.6-7.4%, respectively. Calibration curves were both linear between 2 and 400 ng/mL with a correlation coefficient higher than 0.998. The LC-MS method can be used to quantify the drugs in human plasma in routine analysis. The method proved to be useful in determining real plasma levels in patients involved in cancer therapy. Drug concentrations were determined in a 10 min run-time, including re-equilibration of the column.

The Involvement of Oxidative Stress in Psoriasis: A Systematic Review

Psoriasis is a chronic, immune-mediated inflammatory dermatosis characterized by the appearance of erythematous plaques, covered by white scales, occasionally pruritogenic, and distributed mainly on the extensor areas. Oxidative stress is defined as an imbalance or a transient or chronic increase in the levels of free oxygen/nitrogen radicals, either as a result of the exaggerated elevation in their production or the decrease in their ability to be eliminated by antioxidant systems. Although the pathogenesis of psoriasis remains far from elucidated, there are studies that delineate an involvement of oxidative stress in this skin disorder. Thus, a systematic search was computed in PubMed/Medline, Web of Science and SCOPUS and, in total, 1293 potentially eligible articles exploring this research question were detected. Following the removal of duplicates and the exclusion of irrelevant manuscripts based on the screening of their titles and abstracts (n = 995), 298 original articles were selected for full-text review. Finally, after we applied the exclusion and inclusion criteria, 79 original articles were included in this systematic review. Overall, the data analyzed in this systematic review point out that oxidative stress markers are elevated in psoriasis and share an association with the duration and severity of the disease. The concentrations of these biomarkers are impacted on by anti-psoriasis therapy. In addition, the crosstalk between psoriasis and oxidative stress is influenced by several polymorphisms that arise in genes encoding markers or enzymes related to the redox balance. Although the involvement of oxidative stress in psoriasis remains undisputable, future research is needed to explore the utility of assessing circulating serum, plasma, urinary and/or skin biomarkers of oxidative stress and of studying polymorphisms in genes regulating the redox balance, as well as how can these findings be translated into the management of psoriasis, as well in understanding its pathogenesis and evolution.

Liquid Biopsy and Potential Liquid Biopsy-Based Biomarkers in Philadelphia-Negative Classical Myeloproliferative Neoplasms: A Systematic Review

Myeloproliferative neoplasms (MPNs) are rare, clonal disorders of the hematopoietic stem cell in which an uncontrolled proliferation of terminally differentiated myeloid cells is noted. Polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF) are included in the category of Philadelphia-negative, so-called classical MPNs. The potential applications of liquid biopsy and liquid biopsy-based biomarkers have not been explored in MPNs until now. Thus, a systematic search was computed in PubMed/MEDLINE, Web of Science and The Cochrane Library and, in total, 198 potentially relevant papers were detected. Following the removal of duplicates (n = 85), 113 records were screened. After the exclusion of irrelevant manuscripts based on the screening of their titles and abstracts (n = 81), we examined the full texts of 33 manuscripts. Finally, after we applied the exclusion and inclusion criteria, 27 original articles were included in this review. Overall, the data analyzed in this review point out that liquid biopsy and liquid biopsy-based biomarkers (cell-free DNA, extracellular vesicles, microparticles, circulating endothelial cells) could be used in MPNs for diagnostic and prognostic purposes. Future research is needed to clarify whether this technique can be employed to differentiate between MPN subtypes and secondary causes of erythrocytosis, thrombocytosis and myelofibrosis, as well as to predict the development of thrombosis.

Evaluation of oxidative stress levels in obesity and diabetes by the free oxygen radical test and free oxygen radical defence assays and correlations with anthropometric and laboratory parameters

BACKGROUND

Obesity and diabetes are associated with high levels of oxidative stress. In Romanian patients with obesity and (or) diabetes, this association has not been sufficiently explored.

AIM

To evaluate oxidative stress in obese and (or) diabetic subjects and to investigate the possible correlations between oxidative stress and anthropometric/biochemical parameters.

METHODS

Oxidative stress was evaluated from a single drop of capillary blood. Reactive oxygen species (ROS) were evaluated using the free oxygen radical test (FORT). The free oxygen radical defence (FORD) assay was used to measure antioxidant levels.

RESULTS

FORT levels were higher in obese subjects (3.04 ± 0.36 mmol/L H₂O₂) vs controls (2.03 ± 0.14 mmol/L H₂O₂) (P < 0.0001). FORD levels were lower in obese subjects (1.27 ± 0.13 mmol/L Trolox) vs controls (1.87 ± 1.20 mmol/L Trolox) (P = 0.0072). Obese diabetic subjects had higher FORT values (3.16 ± 0.39 mmol/L H₂O₂) vs non-diabetic counterparts (2.99 ± 0.33 mmol/L H₂O₂) (P = 0.0233). In obese subjects, FORT values correlated positively with body mass index (BMI) (r = 0.48, P = 0.0000), waist circumference (WC) (r = 0.31, P = 0.0018), fasting plasma glucose (FPG) (r = 0.31, P = 0.0017), total cholesterol (TC) (r = 0.27, P = 0.0068) and uric acid (r = 0.36, P = 0.0001). FORD values correlated negatively with BMI (r = -0.43, P = 0.00001), WC (r = -0.28, P = 0.0049), FPG (r = -0.25, P = 0.0130), TC (r = -0.23, P = 0.0198) and uric acid (r = -0.35, P = 0.0002). In obese diabetic subjects, FORT values correlated positively with BMI (r = 0.49, P = 0.0034) and TC (r = 0.54, P = 0.0217). FORD values were negatively associated with BMI (r = -0.54, P = 0.0217) and TC (r = -0.58, P = 0.0121).

CONCLUSION

Oxidative stress levels, as measured by the FORT and FORD assays, were higher in obese subjects vs controls. ROS levels were elevated in diabetic obese patients vs obese non-diabetic patients and controls.

Anticonvulsant effect of anacardic acid in murine models: Putative role of GABAergic and antioxidant mechanisms

Epilepsy is a neurological disease affecting people of all ages worldwide. Side effects of antiepileptic drugs and their association with oxidative stress stimulate the search for new drugs, which would be more affordable with fewer adverse effects. Accordingly, the aim of the present work is to evaluate the anticonvulsant effect of anacardic acid (AA), a natural compound extracted from cashew liquid (Anacardium occidentalis), in murine models, as well as its antioxidant actions in Saccharomyces cerevisiae. AA (>90% purity) was tested, in vivo, in male Swiss mice (25-30 g) with four convulsive models, (1) pentylenetetrazole, (2) pilocarpine, (3) electroshock, and (4) kainic acid, at doses of 25, 50, and 100 mg/kg, body weight (B.W.) Additionally, the effective dose, toxic dose, and protective index studies were also performed. Results revealed that AA exhibits anticonvulsive effects in models 1, 3, and 4, with a mean effective dose (ED₅₀) of 39.64 (model 1) >100 mg/kg, B.W. (model 2), and 38.36 (model 3); furthermore, AA displays a protection index of 1.49 (model 1), <0.6 (model 2, and 1.54 (model 3). In addition, AA showed antioxidant activities in S. cerevisiae mutated for superoxide dismutases (SOD). In conclusion, these results show that AA exhibits significant anticonvulsant and antioxidant activities and may be used as a promising natural product for the treatment of epilepsy.

Andrographolide, a diterpene lactone from Andrographis paniculata and its therapeutic promises in cancer

The diterpene lactone andrographolide, isolated from Andrographis paniculata, has been proven to possess several important protective biological activities, including antioxidant, anti-inflammatory, immunomodulatory, antiseptic, antimicrobial, cytotoxic, hypolipidemic, cardioprotective, hepatoprotective, and neuroprotective effects. In addition, it has been reported to play a therapeutic role in the treatment of major human diseases, such as Parkinson's disease, rheumatoid arthritis, and colitis. This systematic review aims to highlight andrographolide as a promising agent in cancer treatment. To this purpose, a number of databases were used to search for the cytotoxic/anticancer effects of andrographolide in pre-clinical and clinical studies. Among 1703 identified literature articles, 139 were included in this review; 109 were investigated as non-clinical, whereas 24, 3, and 3 were pre-clinical, clinical, and non-pre-clinical trials, respectively. Among the model systems, cultured cell lines appeared as the most frequently (79.14%) used, followed by in vivo models using rodents, among others. Furthermore, andrographolide was found to exert cytotoxic/anticancer effects on almost all types of cell lines with the underlying mechanisms involving oxidative stress, cell cycle arrest, anti-inflammatory and immune system mediated effects, apoptosis, necrosis, autophagy, inhibition of cell adhesion, proliferation, migration, invasion, anti-angiogenic activity, and other miscellaneous actions. After careful consideration of the relevant evidence, we suggest that andrographolide can be one of the potential agents in the treatment of cancer in the near future.

A case of hairy cell leukemia variant

Hairy cell leukemia variant (HCLv) is a rare B-cell chronic lymphoproliferative disorder with features of the classic HCL but presenting some particularities, a poor response to conventional therapy of classic HCL and a more aggressive course of disease with shorter survival than classic HCL. We present a case of a 52-year-old man hospitalized in July 2012 in the Clinic of Hematology of Craiova, Romania, having splenomegaly, leukocytosis with lymphocytosis, anemia and thrombocytopenia, without monocytopenia, which exposed, in the peripheral blood and bone marrow cells, intermediate morphology between hairy cells and prolymphocytes and immunophenotype of mature B-cell phenotype CD19, CD20, CD22, CD11c, CD103, low positive for CD25 and negative for CD3, diagnosed with HCL variant, with no response to conventional chemotherapy and interferon-alpha, an aggressive course of disease and a survival of less than a year from diagnosis.

The occurrence of chronic lymphocytic leukemia after chronic phase of chronic myeloid leukemia: case report and literature review

The occurrence of chronic myeloid leukemia (CML) and chronic lymphocytic leukemia (CLL) in the same patient is a rare event. In published literature, CML diagnosis follows CLL diagnosis or both leukemias are diagnosed simultaneously or rarely, CLL diagnosis follows CML diagnosis. We report the case of one patient with renal adenocarcinoma who was diagnosed with CLL 60 months after CML diagnosis. At that time, the patient was in complete cytogenetic response (CCyR) and major molecular response (MMR) of CML clone according to European LeukemiaNet (ELN) recommendations and presented clinical and hematological signs of progressive CLL clone. After 24 months of regular monitoring, the patient presented signs of CLL clone expansion. The FISH (fluorescence in situ hybridization) analysis for CLL prognostic factors, performed before treatment, was positive for tumor protein p53 (TP53) and 13q14.3 mutations. The Li-Fraumeni syndrome (LFS) was considered but TP53 mutation was considered acquired and patient's reduced overall, progression free and disease free survival might sustained that hypothesis. Imatinib (IM) was stopped and patient received chemotherapy until obtained a stable partial response. Twelve months after last cycle of chemotherapy, the patient received second line treatment due CLL clone progression signs but died due to neutropenia related complications. This article is the first Romanian report of CLL occurrence after CML diagnosis and as far as we know the fourth case report of such association in published literature.

Deficiency Of Antithrombin III (AT III) - Case Report and Review of the Literature

Antithrombin III (AT III) is a plasmatic α-glicoprotein formed by a single peptidic chain. AT III inhibits thrombin (first target) and free Xa, IXa ,VIIa plasmatic factors. In plasma AT III is found under two forms: α-antithrombin and β-antithrombin. Deficiency of AT III represents a risk factor for thromboembolic disease. There are known both quantitative and qualitative AT III deficiencies. Incidence of AT III inherited deficiency is relative rare (1:10.000). Acquired deficiency of AT III is more frequent. The transmission of AT III deficiency is autosomal dominant with variable shield factor. Homozygous is incompatible with life (death immediately after birth). Thrombosis appears around the age of twenty years, and in 4-5 decades of life 2/3 of patients are symptomatics. Traumatisms, surgical interventions, estrogenic treatment, precipitated thrombotic complications. Obesity and dyslipidemic syndrome are risk factors. Thrombosis affects the venous system at these patients. Arterial thrombosis are less reported. The most frequent localisations are: the veins of the legs, mesenteric veins, cave veins, superficial periombilical veins. Treatment of AT III deficiency is: administration of AT III concentrates (with a plasmatic level by 80% from normal value) and heparinotherapy. The treatment with AT III concentrates is for patients which faced major surgical interventions, pregnant women with AT III deficiency. The women with AT III deficiency should avoid the utilisation of oral contraceptives.

Evaluation of parameters with potential prognosis impact in patients with primary gastric diffuse large B-cell lymphoma (PG-DLBCL)

BACKGROUND

Primary gastric lymphoma is the most common malignancy of the stomach after gastric adenocarcinoma. Most cases are represented by the aggressive histological type (diffuse large B-cell lymphoma).

AIM

Identification of factors with potential prognosis impact in the aggressive primary gastric lymphoma and the prognosis profile of the patient with impact on the response to therapy and overall survival.

PATIENTS AND METHODS

The study group is composed of 49 patients diagnosed with primary gastric diffuse large-cell non-Hodgkin's malignant lymphoma at "Fundeni" Hematology Clinic of Bucharest and at the Hematology Clinic of Craiova, Romania, in the period 2005-2010. There were evaluated the following parameters in the attempt to establish correlations between the various studied parameters and the response to treatment, in order to establish the prognosis factors: erythrocyte sedimentation rate (ESR), hemoglobin, serum albumin, serum lactate dehydrogenase (LDH), beta-2 microglobulin, presence of serous infiltration, presence of locoregional adenopathies, bulky tumor, stage of disease, international prognostic index (IPI), quick response to therapy (reduction of >50% in tumor volume after two courses), presence of disease relapses, type of treatment - resection + chemotherapy versus chemotherapy alone, chemotherapy versus chemotherapy + Rituximab.

RESULTS

We found the following negative prognosis factors: the presence of disease relapse, the value of beta-2 microglobulin higher than 3 mg/dL, the presence of serous infiltration, IPI 3.

CONCLUSIONS

Identifying prognostic factors is important for personalized therapy approach to obtain optimal response with minimal adverse reaction.

Refractory anemia with ringed sideroblasts and thrombocytosis without JAK2 V617F mutation: report of three cases

In the WHO classification, there is a provisional entity called Myelodysplastic/Myeloproliferative Neoplasm, Unclassifiable (MDS/MPN, U). Refractory anemia with ringed sideroblasts associated with marked thrombocytosis (RARS-T) was included in this category. Recently published studies report a small percentage of patients with RARS-T. Sixty percent of these have JAK2 V617F mutation, which can suggest the coexistence of two pathological conditions (MDS and MPN). In this paper, we analyzed three patients diagnosed with RARS-T in the Department of Hematology, "Fundeni" Clinical Institute, Bucharest, Romania, during the period 2005-2011. The patients were investigated with cytogenetic exam and molecular biology. In these three cases were identified morphological features of multilineage dysplasia (two-lineage dysplasia in two cases and three-lineage dysplasia in one case). In two cases, thrombocytosis was under 1000×10(3)/μL and clinical evolution was similar to the myelodysplastic syndrome (transfusion dependent anemia with response to administration of erythropoietin). In the third case, the platelets were over 1000×10(3)/μL and with response to the treatment with Hydrea, which improved anemia. JAK2 V617F mutation was not identified in any case. RARS-T remains a provisional entity and requires a complex investigation of patients for the correct diagnosis of these patients. Therapeutic options should be personalized to each case in part because there is not yet a standardized treatment of these patients.

A case of non-Hodgkin lymphoma in a patient with chronic myeloid leukemia

Chronic myeloid leukemia is a clonal expansion of hematopoietic progenitor cells characterized by exaggerated proliferation of granulocytic lineage, with chronic phase, accelerated phase and blast crisis. Accelerated phase and blast crisis may be associated with extramedulary disease. Extramedullary transformation of CML can be determined both in nodal and extranodal sites. Non-Hodgkin lymphoma is rare in chronic myeloid leukemia and may be misdiagnosed as an extramedullary lymphoid blast transformation; the majorities are T-cell lymphomas with an immature thymic phenotype, while peripheral B-cell lymphomas are rarer. We report the case of a 79-year-old woman carrier Ph+ chronic myeloid leukemia who developed at eight months of diagnosis an accelerated phase of CML associated simultaneous with a tumor of soft palate, which was initial considering an extramedullary disease. The patient was treated with specific chemotherapy for accelerated phase of CML (Cytosinarabinoside) + Anagrelide, and reversed to secondary chronic phase of CML, but soft palate tumor persists. The immunohistochemical findings of bone marrow trephine biopsy examination showed chronic phase of CML (negativity for immature cells such as CD34, Tdt) and the biopsy of soft palate tumor and immunohistochemical findings revealed a primitive non-Hodgkin lymphoma (NHL) with medium B-cells (CD20, CD79a positive) and excluding an extramedullary blast crisis (CD34 negative, Tdt negative). Cytogenetic analysis in tumor revealed absence of Philadelphia chromosome. The patient was treated with local radiotherapy for NHL, with a favorable evolution and Hydroxyurea 1 g/day for CML with hematological remission. A localized lymphoid neoplasm may be an extramedullary localized blast crisis of CML or a distinct malignancy, with distinguished therapy and prognosis. A correct diagnosis based on a complex investigation: immunohistochemistry, conventional cytogenetic analysis and fluorescence in situ hybridization (FISH), molecular analysis (Southern blot and RT-PCR) is necessary. Further studies are required to clarify the pathogenetic relationship between chronic myeloid leukemia and non-Hodgkin lymphomas.

Hairy cell leukemia--a rare type of leukemia. A retrospective study on 39 patients

Hairy cell leukemia (HCL) is a chronic B-cell lymphoid leukemia characterized by pancytopenia, splenomegaly, myelofibrosis and the presence in peripheral blood, bone marrow and spleen of atypical lymphoid cells with a hairy aspect. This is a retrospective analysis of 39 patients hospitalized in the Clinic of Hematology, "Filantropia" Municipal Hospital, Craiova, Romania, between 1997-2012, devised by age, sex, and HCL type. Characteristic features of diagnosis (including clinical features, laboratory data: complete blood cell count, differential count, peripheral blood and bone marrow infiltration with atypical lymphoid cells with cytoplasm fine prolongations, immunophenotyping of peripheral blood, bone marrow, spleen or lymph node biopsies with histopathological exams and immunohistochemistry), types of therapy (focused on IFN-α), complications (infections, hemorrhage, autoimmune, second malignancies) and survival rate were monitored. Conclusions of the study revealed the importance of histopathology and immunohistochemistry for diagnosis, of the therapeutic options in the absence of purine nucleoside analogues, the most frequent complications and the decrease of their incidence correlated with therapy and increased count of neutrophils.

Follicular non-Hodgkin's lymphoma: correlation between histology, pathophysiology, cytogenetic, prognostic factors, treatment, survival

BACKGROUND

Folicullar lymphoma (FL) is one of the most common types of all non-Hodgkin's lymphomas (25-40%), characterized by a slowly progressive enlargement of lymph nodes, impairment of hematopoiesis, increased risk to infections, a relatively good prognosis, but usually incurable. Histopathologically, FL has been graded according to the proportion of centroblasts and stratified into grades 1-3: FL grade 1-2 (low-grade), which include cases with few centroblasts, and FL grade 3, divided into grades 3a and 3b, based on the absence of centrocytes in the latter category. Several studies have identified some differences between grade 3a and grade 3b of FL, with most cases of FL grade 3b being more closely related to diffuse large B-cell lymphoma (DLBCL) at molecular level. Several multicenter prospective randomized trials demonstrated an improved outcome when Rituximab (R) was added to chemotherapy for the treatment of follicular non-Hodgkin's lymphomas and a beneficial effect in the quality of life after Rituximab maintenance therapy at these patients.

AIM OF STUDY

To establish some correlation between histology, prognostic factors, treatment and evaluate whether maintenance therapy with anti-CD20+ monoclonal antibodies prolonged progression free survival compared to observation only at the patients with follicular lymphomas treated with R-chemotherapy regimens.

PATIENTS AND METHODS

We studied nineteen patients with follicular non-Hodgkin's lymphomas (grades 1-3) treated with R-CHOP/R-miniCHOP regimens hospitalized in the Clinic of Hematology from Craiova (Romania), between 2008-2011. After these treatments, nine patients with stage III/IV follicular lymphomas were treated with Rituximab maintenance therapy (eight cycles Rituximab 375 mg/m(2), i.v., once every three months for two years) vs. observation only at 10 patients.

RESULTS

In our study, low-grade FL was correlated with a good prognosis at patients with FLIPI score 0-2; the statistical analysis revealed that the progression free survival (PFS) was prolonged at the patients with stage III/IV follicular lymphomas who received Rituximab maintenance therapy compared to the ones with observation only with 1.9 years.

CONCLUSIONS

Low-grade (1-2) FL was correlated with a good prognosis in patients with FLIPI score 0-2; Rituximab maintenance therapy compared with observation only is safe and prolonged progression free survival at patients with follicular lymphomas treated with R-chemotherapy as first line therapy.