Relationship of tryptophan metabolites with the type and severity of multiple sclerosis.

Background: Tryptophan is an essential amino acid primarily metabolized by the kynurenine pathway in mammals. Intermediate metabolites emerging in this pathway have been associated with many neurogenerative diseases. This study aimed to compare tryptophan pathway metabolite levels in patients with multiple sclerosis (MS) and healthy controls and reveal the relationship of tryptophan metabolites with disease subtype and the Expanded Disability Status Scale (EDSS) score.

Oxidative Stress-Related miRNAs in Patients with Severe Acne Vulgaris.

Background: Acne vulgaris is a common chronic inflammatory skin disease in adolescents and oxidative stress plays an important role in acne pathology. However, the pathology of acne has not yet been fully elucidated. miRNAs are small noncoding RNAs, and there is increasing evidence for their role in the pathogenesis of skin diseases such as psoriasis, atopic dermatitis, and other inflammatory diseases.

Assessment of serum neopterin and calprotectin as biomarkers for subclinical inflammation in patients with familial Mediterranean fever.

Background: Familial Mediterranean fever (FMF) is the most common autoinflammatory disease characterized by short, repeated, and self-limiting attacks of fever and serositis. Subclinical inflammation can persist in the periods with no symptoms and result in amyloidosis even with colchicine treatment. Neopterin and calprotectin have been considered essential players in inflammation and immune response.

Raised total methylated arginine load in patients with gout.

The aim of this study was to measure serum levels of methylarginine derivatives and related metabolites in patients with gout. This study enrolled 100 patients with gout and 80 patients in the control group. Serum asymmetric dimethylarginine, symmetric dimethylarginine, L-N-monomethylarginine, arginine, homoarginine, citrulline and ornithine levels were measured with tandem mass spectrometry.

Kynurenine pathway of tryptophan metabolism in patients with familial Mediterranean fever.

Background: Familial Mediterranean fever (FMF) is an autoinflammatory syndrome characterized by recurrent episodes of fever and aseptic polyserositis. Subclinical inflammation generates a hidden threat to the development of FMF complications such as amyloidosis in attack-free intervals. The kynurenine pathway (KP) has been considered an important player in inflammation and immune response.

Determination of serum methylarginine levels by tandem mass spectrometric method in patients with ankylosing spondylitis.

Our aim in this study was to measure serum levels of methylarginines and related metabolites in patients with ankylosing spondylitis (AS), moreover, to investigate the relationship between these parameters and various clinical and laboratory parameters of patients with AS. The study included 60 patients with AS and 60 healthy volunteers. Serum asymmetric dimethylarginine (ADMA), L-N monomethylarginine (L-NMMA), symmetric dimethylarginine (SDMA), arginine (Arg), homoarginine (hArg), ornithine, and citrulline concentrations were measured with tandem mass spectrometry.

Altered methylarginine levels after surgery in subjects with multinodular goiter.

Objectives: Thyroid disorders are important risk factor for cardiovascular diseases. Levels of methylarginines such as asymmetric dimethyl arginine (ADMA), L-monomethyl arginine (L-NMMA), symmetric dimethyl arginine (SDMA) are increase in cardiovascular diseases. Multinodular goiter (MNG) is the most common type of goiter in adults.

Serum ADMA levels were positively correlated with EDSS scores in patients with multiple sclerosis.

Multiple sclerosis (MS) is an autoinflammatory, chronic central nervous system disease. In the pathogenesis of the disease increased nitric oxide (NO) levels play an important role. Nitric oxide (NO) has neuroprotective effects in physiological conditions, however, it is thought that excessive NO formation in MS may lead to demyelination and axonal damage.

The relationship between serum clozapine concentrations and hematological parameters by a validated mass spectrometric method.

Objective: Clozapine is one of the most effective drugs for resistant schizophrenia, but its severe metabolic and hematological side effects limit the use of clozapine. It has been reported that clozapine blood concentrations should be maintained between 350-600 ng/mL. Our aim was to develop a determination method for clozapine and its main metabolites norclozapine and clozapine-N-oxide, to perform validation studies and to investigate the change of various biochemical parameters in patients using clozapine.

Determination of serum imatinib and its' metabolite in patients chronic myeloid leukemia.

Introduction: Imatinib has favorable pharmacokinetic properties, but primary and secondary resistance mechanisms may cause a decrease in clinical response over time. There is a positive correlation between serum imatinib concentrations and treatment response. Our aim was to develop a method for the measurement of imatinib and its' active metabolite N-desmethyl imatinib.