Analysis of one-year follow-up results and treatment costs of patients with PTE in a tertiary care center.

Introduction: Pulmonary thromboembolism (PTE) is a life-threatening disease, with substantial treatment-related complications, difficult follow-up, treatment compliance, and high costs. This study aimed to assess treatment costs with various maintenance therapy regimens, complications, and patient adherence to treatment over a one-year follow-up period. Materials and Methods: This observational, prospective study included 142 patients with PTE who received maintenance anticoagulation therapy between November 2020 and March 2023. The patients were observed at three-month intervals for a year. Possible treatment-related complications, recurrence, mortality, and treatment costs were recorded. Result: Our results showed that there was no significant difference in bleeding risk based on the drugs used for initial or maintenance treatment. In maintenance therapy, low-molecular-weight heparin (LMWH), warfarin, and direct oral anticoagulant (DOAC) treatment regimens had similar treatment adherence and comparable efficacy and safety in terms of recurrence and bleeding (p> 0.05). Four patients (2.8%) were diagnosed with chronic thromboembolic disease. The one-year mortality rate was 24.6% (n= 35), of which 82.9% (n= 29) occurred within the first three months. Hospital mortality rates with the different maintenance therapies were 8.8% in the LMWH group, 5.7% in the warfarin group, and 3.2% in the DOAC group. The annual cost of using LMWH was higher than that of rivaroxaban, apixaban, and warfarin (p< 0.001) while there was no significant cost difference between DOACs and warfarin (p> 0.05). Conclusions: In our study, the LMWH, warfarin, and DOAC treatment regimens had similar efficacy, safety, and patient compliance. In terms of cost, LMWH was the costliest while DOAC and warfarin were similar.

Evaluation of 3-month follow-up of patients with postacute COVID-19 syndrome.

In addition to the highly variable clinical presentation of acute COVID-19 infection, it can also cause various postacute signs and symptoms. This study aimed to evaluate patients with postacute COVID-19 over 12 weeks of follow-up. The study included 151 patients who were diagnosed with COVID-19 by real-time polymerase chain reaction of a nasopharyngeal swab 1 month earlier, had radiologic findings consistent with COVID-19 pneumonia, and presented to the post-COVID-19 outpatient clinic between May and August 2021. The patients were divided into three groups based on COVID-19 severity: nonsevere pneumonia (Group 1), severe pneumonia (Group 2), and severe pneumonia requiring intensive care (Group 3). Evaluation of laboratory parameters at 4 and 12 weeks showed that Group 3 had a higher lactose dehydrogenase (LDH) level and a lower mean platelet volume than the other groups at both time points (p = 0.001 for all). Group 3 also had lower percent predicted forced vital capacity (FVC%), percent predicted forced expiration volume in 1 s (FEV1%), and percent predicted diffusion capacity of the lungs for carbon monoxide divided by alveolar volume (DLCO/VA%) compared to Groups 1 and 2 at Week 4 (p = 0.001, 0.004, 0.001, respectively) and compared to Group 1 at 12 weeks (p = 0.002, 0.03, 0.001, respectively). Patients with persistent dyspnea at 12 weeks had significantly lower FEV1%, FVC%, DLCO/VA%, and saturation levels in room air and significantly higher LDH, pro-BNP, D-dimer, and heart rate compared to those without dyspnea (p = 0.001 for all). Although the lungs are most commonly affected after COVID-19 infection, vascular and endothelial damage also causes multisystem involvement. Our study indicates that laboratory values, radiological signs, and pulmonary functional capacity improved in most patients after 12 weeks of follow-up.

When and how important is anti-fibrotic therapy in the post-COVID-19 period?

PURPOSE: In addition to the highly variable clinical presentation of acute COVID-19 infection, it can also cause various post-acute signs and symptoms. In our study, we aimed to examine the efficacy of anti-fibrotic therapy in patients who developed pulmonary fibrosis after COVID-19. METHODS: In total, 15 patients who applied to the Post-Covid Outpatient Clinic between May 2021 and August 2021 and were diagnosed with COVID-19 pneumonia, and whose cough, dyspnea, exertional dyspnea and low saturation continued to be present at least 12 weeks after the diagnosis, were included in the study. Off-label pirfenidone treatment was started according to the radiological findings, pulmonary function test parameters (PFT) and 6-minute walking test (6MWT) results. The patients were followed up for 12 weeks. RESULTS: While all of the FVC, FVC%, FEV1, FEV1%, DLCO%, DLCO/VA%, 6MWT, and room air saturation levels were observed to increase statistically significantly in the patients at the 12th week, it was determined that there was a statistically significant decrease in the pulse level in room air (p = 0.01, 0.01, 0.01, 0.01, 0.004, 0.001, 0.002, 0.001, and 0.002, respectively). In regression analysis based on radiological scoring, it was observed that the DLCO and room air saturation levels at the 12th week of the treatment were statistically significantly higher in patients with lower scores at the beginning (p = 0.04, 0.03). In addition, it was observed that anti-fibrotic treatment, which was started in the earliest period, i.e., 12 weeks after the diagnosis, resulted in an improvement in radiological, PFT and 6MWT parameters. CONCLUSION: Patients who still had dyspnea and low saturation 12 weeks after the diagnosis, defined as chronic COVID-19, should be evaluated for anti-fibrotic therapy after the necessary radiological and PFT evaluation. Early treatment commencement brings about, besides radiological improvement, a better response obtained in PFT and 6MWT (Tab. 2, Fig. 2, Ref. 21).

Evaluation of the relationship between pentraxin 3 (PTX3) rs2305619 (281A/G) and rs1840680 (1449A/G) polymorphisms and the clinical course of COVID-19.

Macrophage activation syndrome (MAS) is one of the main causes of morbidity and mortality in patients with coronavirus disease 2019 (COVID-19). This study aimed to investigate the relationship between the pentraxin 3 (PTX3) gene polymorphisms rs2305619 (281A/G) and rs1840680 (1449A/G) and the development of MAS in patients with COVID-19. The study included a total of 94 patients aged 18-45 who were diagnosed as having COVID-19 between June and December 2020. PTX3 281A/G and 1449A/G polymorphism frequencies were evaluated. PTX3 281A/G allele and genotype frequencies did not deviate from Hardy-Weinberg (HW) equilibrium in the MAS or non-MAS group (χ2 : 0.049, df: 2, p = 0.976, χ2 : 0.430, df: 2, p = 0.806). PTX3 1449A/G allele and genotype frequencies deviated significantly from HW equilibrium in the non-MAS group (χ2 : 6.794, df: 2, p = 0.033) but not in the MAS group (χ2 : 2.256, df: 2, p = 0.324). The AG genotype was significantly more frequent in the non-MAS group, while the AA genotype was significantly more frequent in the MAS group (χ2 : 11.099, df: 2, p= 0.004). Analysis of the PTX3 1449A/G polymorphism showed that individuals with the GG genotype had higher serum PTX3 levels than those with the AA and AG genotypes (p = 0.001 for both). Analysis of the PTX3 1449A/G polymorphism in patients with COVID-19 showed that those with the AG genotype were relatively more protected from MAS compared with individuals with the AA genotype. In addition, lower serum PTX3 levels are observed in patients carrying the A allele.

Comparison of high-flow and conventional nasal cannula oxygen in patients undergoing endobronchial ultrasonography.

BACKGROUND: Oxygen therapy is required to prevent hypoxaemia during the endobronchial ultrasonography (EBUS) procedure. AIMS: To compare the effectiveness of oxygen therapy delivered through high-flow nasal cannula (HFNC) and conventional nasal cannula (CNC) in patients undergoing EBUS. The primary outcome was the proportion of patients who desaturated. Patient compliance and satisfaction were also evaluated. METHODS: This single-centre prospective interventional study was conducted in a tertiary hospital among patients who presented to the EBUS unit in 2018 and 2019. Patients were randomly assigned to the HFNC group or the CNC group. RESULTS: The study included 170 patients (111 men and 59 women) with a mean age of 58 ± 14 years. The number of patients experiencing desaturation while receiving oxygen was statistically significantly lower (P < 0.001) in the HFNC group (n = 5) compared with the CNC group (n = 26). Oxygen therapy was adjusted in two patients in the CNC group due to desaturation. Saturation was significantly higher in the HFNC group (P < 0.0001) at the end of the EBUS procedure. Heart rate at the end of EBUS was lower in the HFNC group, but this difference was not statistically significant (96 ± 16 vs 101 ± 19, P = 0.13). Five patients in the HFNC group and 18 patients in the CNC group reported discomfort during the procedure (P = 0.006). CONCLUSION: Oxygen therapy delivered by HFNC seems to be safer and more effective than by CNC in patients undergoing EBUS. Oxygen therapy with HFNC may be considered as an alternative to CNC because it may increase patient comfort and thereby improve compliance.

Is endogenous carboxyhaemoglobin level a useful biomarker of clinical course and prognosis in COVID-19 patients?

OBJECTIVE: SARS-CoV-2 has caused nearly 4 million confirmed cases of COVID-19 worldwide in the approximately 4 months since it emerged in Wuhan, China in December 2019. Comorbidities increase morbidity and mortality in COVID-19, and many laboratory parameters have been associated with mortality. The aim of the present study was to identify the relationship between endogenous carboxyhaemoglobin (COHb) level and the clinical course and prognosis of COVID-19. METHODS: The study included 48 non-smokers or ex-smokers aged 18 years or older who presented to the emergency department, were diagnosed with COVID-19 by real-time PCR analysis of nasopharyngeal swab sample and were treated in the pulmonary diseases ward of the Atatürk University hospital after 24 March 2020 and 15 April 2020. The patients' laboratory parameters and demographic data were analysed retrospectively. RESULTS: Prothrombin time and C-reactive protein (CRP), troponin-I, and D-dimer levels decreased in COVID-19 patients during follow-up (P = .024, P = .001, P = .001, P = .001), while PaO2 /FiO2 ratio and COHb increased (P = .002, P = .001). COHb level at admission was significantly lower in patients who developed macrophage activation syndrome (MAS), acute respiratory distress syndrome (ARDS), and those who died compared with the other patients (P = .002, P = .001). COHb level on day 5 of treatment was significantly higher in patients with ARDS and patients who died (P = .001, P = .001). Significant correlations were detected between COHb level and CRP (r=-0.425, P = .001), ferritin (r = -.395, P = .001) and PaO2 /FiO2 ratio (r = .431, P = .001). CONCLUSIONS: COHb level may be an easily accessible biomarker that guides early follow-up and treatment planning to avoid ARDS, MAS and mortality in COVID-19.

Association of plasma netrin-1 level with inflammatory balance and comorbidities in patients with acute exacerbation of COPD.

INTRODUCTION: Chronic obstructive pulmonary disease (COPD) is a common lung disease characterized by airflow restriction and systemic inflammation. Netrin-1 is a protein mainly produced in the central nervous system and has proven anti-inflammatory activity. The aim of this study was to determine netrin-1 level and its relationship with comorbidities in patients with acute exacerbation of COPD. MATERIALS AND METHODS: The study included 232 patients aged over 40 years who were divided into 3 groups: Group 1: ex-smokers (≥ 20 pack-years) with COPD hospitalized for COPD exacerbation (n= 142), Group 2: current-smokers (≥ 20 pack-years) without COPD (n= 30), Group 3: a control group comprising healthy non-smokers (n= 60). Plasma netrin-1 levels were measured using commercial enzyme-linked immunosorbent assay (ELISA) kit. RESULT: There were significant differences in forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), FEV1/FVC, C-reactive protein (CRP), and plasma netrin-1 levels between patients with acute exacerbation of COPD and current smokers without COPD, healthy controls (p= 0.001 for all). Netrin-1 levels at discharge were lower in COPD patients with diabetes mellitus (DM) compared to nondiabetic COPD patients (p= 0.01). Weak correlation was observed between netrin-1 level at admission and FEV1, FVC, partial pressure of oxygen, and CRP levels (r= 0.394, p= 0.01; r= -0.366, p= 0.01; r= -0.19, p= 0.05; r= 0.306, p= 0.01). Netrin-1 level at admission was also moderately correlated with smoking history (pack-years) (r= 0.579, p= 0.01). CONCLUSIONS: Netrin-1 was elevated in acute exacerbation of COPD and may be an important element in inflammatory balance. Patients with both COPD and DM were found to have lower netrin-1 levels at discharge after resolution of the acute exacerbation.

Are Serum Interleukin 6 and Surfactant Protein D Levels Associated with the Clinical Course of COVID-19?

PURPOSE: SARS-CoV-2 (COVID-19) has infected more than 7 million people worldwide in the short time since it emerged in Wuhan, China in December 2019. The aim of this study was to investigate the relationship between serum interleukin 6 (IL-6) and surfactant protein D (SP-D) levels and the clinical course and prognosis of COVID-19. MATERIALS AND METHODS: The study included a total of 108 individuals: 88 patients who were diagnosed with COVID-19 by real-time PCR of nasopharyngeal swab samples and admitted to the Atatürk University Pulmonary Diseases and the Erzurum City Hospital Infectious Diseases department between March 24 and April 15, and 20 asymptomatic healthcare workers who had negative real-time PCR results during routine COVID-19 screening in our hospital. RESULTS: Patients who developed macrophage activation syndrome had significantly higher IL-6 and SP-D levels at the time of admission and on day 5 of treatment compared to the other patients (IL-6: p = 0.001 for both; SP-D: p = 0.02, p = 0.04). Patients who developed acute respiratory distress syndrome had significantly higher IL-6 and SP-D levels at both time points compared to those who did not (p = 0.001 for all). Both parameters at the time of admission were also significantly higher among nonsurvivors compared to survivors (IL-6: p = 0.001, SP-D: p = 0.03). CONCLUSION: In addition to IL-6, which has an important role in predicting course and planning treatment in COVID-19, SP-D may be a novel pneumoprotein that can be used in the clinical course, follow-up, and possibly in future treatments.

Is Vimentin the Cause or Effect of Obstructive Sleep Apnea Development?

PURPOSE: In obstructive sleep apnea (OSA), hypoxia secondary to apnea and hypopnea and the resulting systemic inflammatory response are the main causes of comorbidities. The aim of this study was to investigate the relationship between OSA and vimentin, which plays an important role in the activation of cells that synthesize inflammatory cytokines. MATERIALS AND METHODS: The study included 150 OSA patients (50 mild, 50 moderate, and 50 severe OSA) and 50 patients without OSA as a control group. Plasma vimentin levels were measured from peripheral blood samples using a commercial enzyme-linked immunosorbent assay (ELISA) kit. RESULTS: The OSA patients in our study had significantly higher body mass index, apnea-hypopnea index (AHI), triglyceride level, mean oxygen desaturation, and plasma vimentin levels compared to the healthy control group (p = 0.007, 0.001, 0004, 0.001, and 0.001, respectively). Plasma vimentin level was significantly higher in the moderate and severe OSA groups compared to the control and mild OSA groups (p = 0.001 for all). There was no difference between severe and moderate OSA. There were significant correlations between plasma vimentin levels and OSA patients' AHI and mean oxygen desaturation (r = 0.46, p = 0.001; r = 0.214, p = 0.005). CONCLUSION: In this study, we observed significant positive correlations between plasma vimentin level and OSA severity, weight, AHI, and mean oxygen desaturation. Vimentin may have utility as a biomarker in the follow-up and treatment of OSA.

The association of OSAS and uvula: the role of MRI in this egg-chicken problem in OSAS.

PURPOSE: Obstructive sleep apnea syndrome (OSAS) is a condition resulting from repetitive partial or complete upper airway obstruction, and its etiology remains uncertain. Polysomnography is the gold standard diagnostic test for OSAS. However, there are long wait times for this evaluation, so questionnaires or ancillary diagnostic methods are used to select appropriate patients. One of these is magnetic resonance imaging (MRI). The present study aimed to investigate the association between clinical features of OSAS and uvular changes on MRI. MATERIALS AND METHODS: A total of 102 participants, 80 with OSAS and 22 controls, were included in the study. All participants underwent full-night polysomnography, MRI, and anthropometric measurements. RESULTS: In comparisons of MRI measurements of the uvula, statistically significant differences in uvular length, thickness, and angle were observed between the OSAS and control groups. MRI measurement significantly associated with apnea-hypopnea index was uvular thickness. Evaluation of anthropometric and MRI measurements revealed statistically significant associations between waist circumference and uvular thickness, uvular width, and oropharyngeal space among the OSAS patients. CONCLUSION: Thickened uvula on MRI is associated with the presence of OSAS, and its thickness is well correlated with the severity of the diseases. Thus, it may be a reliable indicator of OSAS and could be used as a supportive finding to identify patients suitable for referral for diagnostic polysomnography.

A massive pulmonary thromboembolism after pulmonary endarterectomy: A case report.

Pulmonary endarterectomy is a first choice treatment for chronic thromboembolic pulmonary hypertension which may be a complication of pulmonary thromembolism. Here, we present a 70-year-old female who admitted to our clinic with acute massive pulmonary thromboembolism after a pumonary endarterectomy operation because of non-compliance to anticoagulation treatment.

Evaluation of the relationship of serum vitamin D levels in COVID-19 patients with clinical course and prognosis.

INTRODUCTION: SARS-CoV-2 (COVID-19), which emerged in Wuhan, China in December 2019, infected more than six million people in a short time. In COVID-19, the relationship of many laboratory parameters to morbidity and mortality has been defined. In our study, we aimed to determine the relationship of serum vitamin D level to clinical course and prognosis. MATERIALS AND METHODS: This study included 108 patients; 88 patients who stayed in Ataturk University and Erzurum City Hospital between March 24, 2020 and May 15, 2020, who were identified as COVID-19 by real-time PCR method from the nasopharyngeal swab and 20 asymptomatic voluntary medical personnel who tested negative for real-time PCR after routine check-up in our hospital. RESULT: In statistical analysis conducted between healthy control group and vitamin D levels of patients admitted due to COVID-19, it was observed that patients infected with COVID-19 had a lower level (p= 0.004). In 20 patients developing MAS, a lower level of vitamin D was observed (p= 0.004) compared to 68 patients who did not develop. In the comparison of vitamin D levels of the patients (n= 8) who developed exitus in their follow up due to COVID-19, it was observed that vitamin D levels were statistically significantly lower compared to the living (p= 0.009). CONCLUSIONS: Due to COVID-19, pandemic, long-running quarantines caused insufficient use of sunlight and worsening of vitamin D deficiency. We wanted to draw attention again with our study to vitamin D which can be responsible for the heavy clinical course of COVID-19 and whose replacement is easy to apply.

Can tissue elemental analysis be used to differentiate sarcoidosis and tuberculous lymphadenitis?

INTRODUCTION: Sarcoidosis and tuberculous lymphadenitis are granulomatous inflammatory diseases. Differentiating lymph node involvement in these two diseases can be challenging. This study evaluated whether elemental analysis of tissue samples could facilitate the differentiation of these histopathologically and clinically similar diseases. MATERIALS AND METHODS: A total of 152 tissue samples were included: 57 caseating granulomatous inflammation, 58 non-caseating granulomatous inflammation, and 37 reactive lymph node specimens. The tissue samples were analyzed for calcium, magnesium, iron, copper, zinc, chrome, molybdenum, nickel and selenium with inductively coupled plasma-optical emission spectroscopy (ICP-OES). RESULT: Comparison of element levels in the three groups revealed that caseating granulomatous inflammation had higher calcium content (662.6 ± 4.6 ppm, p< 0.001) and lower iron content (48.7 ± 83 ppm, p< 0.001) compared to non-caseating granulomatous inflammation. Compared to reactive lymph tissue, caseating granulomatous inflammation had higher calcium and lower iron and magnesium content while non-caseating granulomatous inflammation had higher levels of iron and lower magnesium; however, these differences were not statistically significant. In caseating granulomatous inflammation, a calcium cut-off value of 207 ppm yielded 85% specificity and 63% sensitivity. For iron, a cut-off value of 51 ppm had 74% specificity and 58% sensitivity. CONCLUSIONS: High calcium and low iron levels in lymph tissue may be suggestive of caseating granulomatous inflammation and tuberculosis. In cases where differentiating between sarcoidosis and tuberculous lymphadenitis is difficult, performing tissue elemental analysis may provide additional supportive evidence for differential diagnosis.

Could HIF-1α be a novel biomarker for the clinical course and treatment of pulmonary embolism?

Background/aim: Pulmonary embolism (PE) is associated with high morbidity and mortality rates if not diagnosed and treated rapidly. The aim of our study was to investigate the relationship between levels of hypoxia-induced factor-1 alpha (HIF-1α) and clinical course and prognosis in patients with intermediate low-risk, intermediate high-risk, and high-risk PE. Materials and methods: The study included 240 subjects in 4 groups: a healthy control group (n = 60, mean age = 60 ± 15.2, female/male = 30/30 ), intermediate low-risk PE group (n = 60, mean age = 60 ± 12,5, female/male = 27/33), intermediate high-risk PE group (n = 60, mean age = 61,4 ± 14,8, female/male = 36/24), and high-risk PE group (n = 60, mean age = 62,3 ± 15, female/male = 33/27). Plasma HIF-1α levels were measured using commercial enzyme-linked immunosorbent assay (ELISA) kit. Results: Comparison of HIF-1α levels revealed a statistically significant difference between the groups in proportion to clinical scoring (P = 0.001 for all). Comparison of initial HIF-1α and troponin levels in intermediate high-risk PE patients given thrombolytic therapy and those treated with enoxaparin sodium showed that HIF-1α levels were significantly higher in the group that received thrombolytic therapy (P = 0.001), while there was no difference in troponin levels (P = 0.146). Conclusion: HIF-1α can be used in the PE clinical risk stratification and monitoring of PE and may also serve as a valuable early indicator in intermediate high-risk PE, for which early reperfusion therapy is important.

The Frequency of Monocyte Chemoattractant Protein-1 Gene Polymorphism in Obstructive Sleep Apnea Syndrome.

PURPOSE: In obstructive sleep apnea syndrome (OSAS) many proinflammatory cytokines are released from activated endothelial cells due to repeated decreases in arterial oxygen saturation. Some of these proinflammatory cytokines are involved in the etiology of coronary artery disease (CAD). Although the association between OSAS and CAD is known, risk factors for CAD have not been determined in this patient group. Monocyte chemoattractant protein-1 (MCP-1) is a proinflammatory cytokine that plays a key role in the development of atherosclerosis. In this study, we compared the frequency of MCP1 rs1024610-rs1024611 single-nucleotide polymorphisms (SNPs) in OSAS patients with no comorbidity, OSAS patients with no comorbidity except CAD, and healthy individuals. MATERIAL AND METHODS: The study included 301 subjects. Two hundred one patients with OSAS (OSAS only and OSAS + CAD groups) and 100 healthy control subjects underwent polysomnography. MCP1 rs1024610 and rs1024611 mutation frequencies were determined. RESULTS: Body mass index, apnea-hypopnea index, triglyceride levels, and mean oxygen desaturation were significantly higher in the OSAS patients than in the healthy population (p < 0.05). In MCP1 rs1024611 SNP analysis, homozygous mutation was significantly more common in the OSAS + CAD group than in the OSAS and control groups (p < 0.001). MCP1 rs1024610 SNP analysis showed no significant differences among the study groups. CONCLUSION: OSAS patients with homozygous MCP1 rs1024611 SNP are at higher risk for CAD. The MCP1 rs1024610 SNP was not associated with incidence of CAD. Patients with OSAS and MCP1 rs1024611 homozygous mutation are more susceptible to CAD and early detection and treatment may significantly reduce mortality and morbidity.

A novel, rapid and sensitive UPLC-MS/MS method for the determination of macitentan in patients with pulmonary arterial hypertension.

Macitentan is an endothelin receptor antagonist commonly used in the treatment of pulmonary arterial hypertension (PAH). A novel, rapid, simple and sensitive UPLC-MS/MS method was developed and validated for pharmacokinetic study and the determination of macitentan in PAH patients. Macitentan and bosentan, which are used as internal standards, were detected using atmospheric pressure chemical ionization in positive ion and multiple reaction monitoring mode by monitoring the mass transitions m/z 589.1 → 203.3 and 552.6 → 311.5, respectively. Chromatographic separation was performed on a reverse-phase C18 column (5 µm, 4.6 × 150 mm) with an isocratic mobile phase, which consisted of water containing 0.2% acetic acid-acetonitrile (90:10, v/v) at a flow rate of 1 mL/min. Retention times were 1.97 and 1.72 min for macitentan and IS, respectively. The calibration curve with high correlation coefficient (0.9996) was linear in the range 1-500 ng/mL. The lower limit of quantitation and average recovery values were determined as 1 ng/mL and 89.8%, respectively. This method is the first UPLC-MS/MS method developed and validated for the determination of macitentan from human plasma. The developed analytical method was fully validated for linearity, selectivity, specificity, accuracy, precision, sensitivity, stability, matrix effect and recovery according to US Food and Drug Administration guidelines. The developed method was applied successfully for pharmacokinetic study and the determination of macitentan in PAH patients.

The effect of unilateral forced nostril breathing on sleep in healthy right-handed men: a preliminary report.

PURPOSE: Although we spend about one-third of our lives in sleep and recognize its necessity for good health, sleep has only been partially elucidated in the last century. The nasal cycle of congestion and decongestion during sleep has various effects on human physiology. The aim of the present study was to investigate the effect of unilateral forced nostril breathing on sleep. METHODS: Twenty-one healthy male volunteers aged 18-24 years were included in the study. Only individuals with right-hand dominance were included. Subjects were observed during sleep for three nights under different conditions: no obstruction (normal sleep) on the first night, right nasal obstruction on the second night, and left nasal obstruction on the third night. RESULTS: The main findings of our study are that sleep efficiency, NREM stage III, and total sleep duration were greater during left nasal obstruction (right nostril dominant respiration), while apnea-hypopnea index (AHI), frequency of periodic limb movements, and oxygen desaturation were higher during right nasal obstruction (left nostril dominant respiration). CONCLUSION: The nasal cycle has a significant impact on sleep which is reflected in sleep recordings. Our result supports that nasal obstructions, due to deviations, concha hypertrophy, or congestion/decongestion, might affect the physiology of respiration and sleep. Nasal obstruction should be taken into consideration when evaluating patients in sleep laboratories and further studies are required to elucidate the situation in the patients with nasal obstruction.

The effect of surgical specimen-derived phosphorus and lead concentrations in non small cell lung cancer patients on disease course.

INTRODUCTION: Lung cancer is one of the leading causes of cancer-related mortality. There are many exogenic and endogenic factors associated with the development of lung cancer. One of these factors is trace elements. Under- or overabundance of trace elements can disrupt cellular functions and lead to the formation of cancer. In this study we conducted elemental analysis of lung cancer tissue and normal lung tissue to investigate the role of tissue trace element concentrations in lung cancer. MATERIALS AND METHODS: Elemental analysis was performed on 30 lung cancer tissue samples and a control group of 15 normal lung tissue samples, all taken from patients diagnosed, treated and followed at our hospital between 2005 and 2010. The solubilized tissue samples were analyzed for the presence of 19 elements using inductively coupled plasma-optical emission spectroscopy (ICP-OES). Total element amounts in the tissue were calculated. RESULT: Concentrations of magnesium, potassium, zinc, manganese, lead, boron, chromium and phosphorus were significantly higher in the patient group compared to the control group. Deceased patients had significantly lower phosphorus concentrations and significantly higher lead concentrations than the other patients. CONCLUSIONS: Elevated levels of magnesium, potassium, zinc, manganese, lead, boron, chromium and phosphorus in lung cancer tissue indicate that these elements may play a role in the development of lung cancer. The results of our evaluation of the association between trace elements and lung cancer suggest that, together with other factors, low phosphorus concentration and high lead concentration in tumor tissue may influence disease course.

Predictive Value of Mean Platelet Volume for Pulmonary Embolism Recurrence.

PURPOSE: Recurrence is a major clinical problem in patients with pulmonary embolism and can affect mortality. The decision to discontinue treatment is important for recurrence and is based on patients' clinical features as well as certain blood parameters. Our aim in this study was to evaluate whether mean platelet volume (MPV) and platelet distribution width (PDW) have utility as new predictive parameters for recurrence and mortality in pulmonary embolism. MATERIALS AND METHODS: A total of 440 patients with pulmonary embolism underwent computed tomography, Doppler ultrasonography, and echocardiography before and at the conclusion of treatment. Thrombocyte count, MPV, PDW, and D-dimer parameters were also evaluated at the same time points. RESULTS: MPV and PDW were significantly higher in deceased patients (8.8 ± 1.2 fl and 17.4 ± 0.8) compared to surviving patients (7.7 ± 0.9 fl and 17 ± 0.9) (p < 0.0001). Initial MPV and PDW were also significantly higher in patients with recurrence (8.4 ± 0.7 vs 7.6 ± 0.8 fl, p < 0.0001 and 17.3 ± 0.8 vs 16.9 ± 0.9, p = 0.002, respectively) than in patients without recurrence. At the end of treatment, MPV was still higher in patients with recurrence compared to patients without recurrence (8.7 ± 0.5 and 7.5 ± 0.7 fl, respectively, p < 0.0001). MPV values over 8.05 fl at the end of treatment predicted recurrence with 91% sensitivity and 77% specificity. CONCLUSION: MPV seems to be an indicator of recurrence in pulmonary embolism and may have utility in the prediction of recurrence. Elevated MPV can also be used to predict mortality in pulmonary embolism.

Added value of DCE-MRI in the management of cystic-cavitary lung lesions.

BACKGROUND AND OBJECTIVE: We evaluated the added value of dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) to CT in the evaluation of cystic-cavitary lung lesions. We aimed to compare morphological parameters, including wall thickness and inner wall irregularity, and to determine whether DCE-MRI with morphological and dynamic parameters was useful in indeterminate lesions. We also aimed to investigate the added value of DCE-MRI in terms of whether to biopsy, and if so the site of biopsy. METHODS: This prospective study included 39 consecutive patients with cystic and/or cavitary lung lesions detected by CT who then underwent additional DCE-MRI. After initial evaluation, the lesions were classified as benign, indeterminate or malignant and the findings of CT and DCE-MRI compared with each other by considering the final diagnosis that was determined by histopathological findings and clinical evaluation and follow up. RESULTS: The mean values for wall thickness obtained by DCE-MRI were lower and the range of wall thickness for indeterminate lesions was narrower than those obtained by CT (5.50-11.50 mm and 5.75-13.50 mm for DCE-MRI and CT), and inner wall irregularity on DCE-MRI was more sensitive in malignant lesions. Also, DCE-MRI obviated biopsy in three benign patients and changed the biopsy site in two patients. CONCLUSION: Our study suggests that DCE-MRI is helpful in indeterminate cystic-cavitary lung lesions, with morphological and dynamic features. It narrowed the range of wall thickness used for indeterminate lesions, was more sensitive than CT in determining malignant inner wall irregularity, and was also useful in determining the need for and appropriate site of biopsy. See article, page 576.