Comparison of serological markers between ACPA<Superscript>+</Superscript> and ACPA<Superscript>−</Superscript> of RA patients

Anti-citrullinated protein/peptide antibodies (ACPA) have recently emerged as sensitive and specific serological markers of rheumatoid arthritis (RA), providing superior alternative of the rheumatoid factor (RF) test in the laboratory diagnostics of RA. We compare the change of serum RF, CRP, IgG, IgM, IgA, total complement, C3 and C4. The sera sample was collected from 123 patients with RA. ACPA were detected with ELISA, and RF, CRP and total complement (Ct), C3 and C4 were examined by automatic biochemical analyzer. Serum RF and total complement concentrations were significantly higher in ACPA+ than in ACPA−, but there were no correlation between ACPA and RF and Ct. Between ACPA+ and ACPA−, there were no significant difference of CRP, IgG, IgM, IgA, total complement, C3 and C4. While there were significant correlation between the concentration of C3 and IgM and ACPA in ACPA+. Conclusion: This is the first study to show that ACPA concentration in ACPA+ patients with RA is positively related to serum IgM and C3 levels.     

Emerging therapies in transthyretin amyloidosis – a new wave of hope after years of stagnancy?

Transthyretin amyloidosis (ATTR) is a rare, yet underdiagnosed disease characterized by progressive impairment of neurologic and cardiac function due to deposition of misfolded transthyretin. Despite great efforts, such as the introduction of orthotopic liver transplant, the devastating prognosis for both variant and wild‐type ATTR patients remained unchanged over the last decades, mainly due to a lack of specific therapies. Fortunately, recent years saw the introduction of promising targeted therapies, which aim to interfere with the deposition of misfolded transthyretin (TTR) at various stages of the cascade underlying ATTR progression. These include TTR tetramer stabilizers (tafamidis, diflunisal, epigallocatechin‐3‐gallate), TTR silencers (inotersen, patisiran) and fibril disruptors (monoclonal antibodies, doxycycline and tauroursodeoxycholic acid). In the context of this review we explain their mechanisms of action, analyse their efficacy on neurologic and cardiac function based on all clinical trials conducted to date and discuss their clinical applicability. Eventually suggestions for future clinical research into the field are provided.     

Analysis of the 3′ Variable Region of the <Emphasis Type="Italic">cagA</Emphasis> Gene of <Emphasis Type="Italic">Helicobacter pylori</Emphasis> Isolated in Koreans

CagA protein of Helicobacter pylori is injected into epithelial cells, and it undergoes tyrosine phosphorylation, resulting in inducing cytoskeletal rearrangements. A few studies have suggested that the number of CagA tyrosine phosphorylation motifs (EPIYA) and subtypes of CagA were associated with gastric cancer. This study was performed to characterize the 3' variable regions of the cagA gene of H. pylori and to investigate whether or not there is any relationship between the diversities of cagA and the disease outcome in Korea. Seventy-nine patients (chronic gastritis, 15; duodenal ulcer, 27; benign gastric ulcer, 18; gastric cancer, 19) were enrolled. Biopsy specimens were taken from the antrum for H. pylori culture, and genomic DNA was extracted. PCR and DNA sequence analysis was carried out for the 3′ variable region of the cagA gene. Seventy-eight strains (98.8%) contained three EPIYA motifs and one strain (1.2%) isolated from a patient with duodenal ulcer contained four EPIYA motifs. Seventy-six strains (96.2%) were the East Asian type. In conclusion, there was no significant difference between the number of EPIYA motifs or CagA subtypes and various gastroduodenal diseases in Korea.     

Effects of the inhibition of cytosolic phospholipase A<Subscript>2</Subscript>α in non-small cell lung cancer cells

Purpose  

The aim of this study was to investigate the expression of cPLA₂α in non-small lung cancer cell lines and tissues, and we sought to determine the in vitro effects of the pyrrolidine-2 inhibitor on cPLA₂α sensitivity in three different non-small lung cancer cell lines.     

Clinical Efficacy of Inhaler Devices Containing β<Subscript>2</Subscript>-Agonist Bronchodilators in the Treatment of Asthma

Background: A number of different inhaler devices are available to deliver β₂-adrenoceptor agonist (β₂-agonist) bronchodilators in asthma. These include hydrofluoroalkane or chlorofluorocarbon (CFC)-free propelled pressurized metered-dose inhalers (pMDIs), many dry powder inhalers and breath-actuated inhalers. Objective: To determine the clinical efficacy of all available hand-held inhaler devices compared with the standard CFC-containing pMDI for the delivery of short-acting β₂-agonist bronchodilators in nonacute asthma in both children and adults. Methodology: A systematic review and meta-analysis was carried out of all available randomized, controlled trials (RCTs) using the standard pMDI compared with any other hand-held inhaler device, delivering short-acting β₂-agonist bronchodilators in patients with stable asthma. Results: One hundred and eighteen RCTs were included in this review. No clinical differences were found between the standard CFC-containing pMDI and 12 other hand-held inhaler devices for most outcome measures. We found no evidence of clinical differences between studies using either a 1 : 1 (pMDI: another inhaler) or a 2 : 1 dosing ratio. Conclusions: In patients with stable asthma, short-acting β₂-agonist bronchodilators in standard CFC-pMDIs are as effective as any other hand-held inhaler device; therefore the cheapest available device that the patient is able to use should always be considered. Pharmaceutical companies should in future submit to regulatory authorities clinical outcome data (as opposed to in vitro data) in support of any dosing schedules greater than 1 : 1 when compared with the standard pMDI. Clinical effectiveness studies that use an intention-to-treat analysis and report more patient-centered outcomes are required.     

In vivo assessment of stent recoil of biodegradable polymer-coated cobalt–chromium sirolimus-eluting coronary stent system

IntroductionImmediate and acute stent recoil has been observed following balloon deflation in normal and diseased coronary arteries, and the degree varies by stent design.MethodsA total of 19 patients, who underwent elective stent implantation for single de novo native coronary artery lesions, were enrolled: all patients treated with the biodegradable polymer-coated sirolimus-eluting cobalt–chromium coronary stent system (Supralimus-Core^®). The immediate, acute and cumulative stent recoil was assessed by quantitative coronary angiography. The cumulative stent recoil was measured at 24 h of stent implantation.ResultsThe absolute late loss due to recoil was found 0.08 ± 0.19 mm for Immediate Stent Recoil (ISR), 0.05 ± 0.21 mm for Acute Stent Recoil (ASR) and 0.11 ± 0.25 mm for Cumulative Stent Recoil (CSR) respectively.ConclusionsIn vivo acute stent recoil of the Supralimus-Core^® has higher radial strength compared to other available standard drug-eluting stents.     

Does Nonresponse Bias the Results of Retrospective Surveys of End‐of‐Life Care?

OBJECTIVES: To evaluate the effect of nonresponse bias on reports of the quality of end‐of‐life care that older adults receive. DESIGN: Nationwide retrospective survey of end‐of‐life care. SETTING: Sixty‐two Veterans Affairs Medical Centers. PARTICIPANTS: Patients were eligible if they died in a participating facility. One family member per patient was selected from medical records and invited to participate. MEASUREMENTS: The telephone survey included 14 items describing important aspects of the patient's care in the last month of life. Scores (0–100) reflect the percentage of items for which the family member reported that the patient received the best possible care, and a global item defined the proportion of families who said the patient received “excellent” care. To examine the effect of nonresponse bias, a model was created to predict the likelihood of response based on patient and family characteristics; then this model was used to apply weights that were equivalent to the inverse of the probability of response for that individual. RESULTS: Interviews were completed with family members of 3,897 of 7,110 patients (55%). Once results were weighted to account for nonresponse bias, the change in mean individual scores was 2% of families reporting “excellent” care. Of the 62 facilities in the sample, the scores of only 19 facilities (31%) changed more than 1% in either direction, and only 10 (16%) changed more than 2%. CONCLUSION: Although nonresponse bias is a theoretical concern, it does not appear to have a significant effect on the facility‐level results of this retrospective family survey.     

Is a “false‐positive” clinical diagnosis of knee osteoarthritis just the early diagnosis of pre–radiographic disease?

Objective

In routine practice, diagnosis of knee osteoarthritis (OA) currently relies on the combination of conventional risk factors and the presence of cardinal signs and symptoms. However, their role in early diagnosis has received little attention compared with biomarker research.

Methods

Using data from 122 adults ages ≥50 years with knee pain but no definite radiographic OA, we tested whether the clinical diagnostic probability of OA, based on risk factors, signs, and symptoms, was associated with subsequent incidence of radiographic OA 3 years later.

Results

Clinical diagnostic probability performed only modestly in discriminating incident radiographic knee OA (area under the receiver operating characteristic curve = 0.59, 95% confidence interval 0.49–0.70).

Conclusion

Improving the measurement of conventional markers and using study designs that test the ability of new biomarkers to add to or replace conventional markers are priorities for research in the early diagnosis of OA.     

Pharmacological Stimulation of β <Subscript>2</Subscript>-adrenergic Receptors (β <Subscript>2</Subscript>AR) Enhances Therapeutic Effectiveness of β <Subscript>1</Subscript>AR Blockade in Rodent Dilated Ischemic Cardiomyopathy

Background. We have reported that β ₂ adrenoreceptor (β ₂AR) stimulation is anti-apoptotic, and has strong beneficial effect on cardiac remodeling in an experimental model of post myocardial infarction chronic heart failure (CHF) in rats. Here we investigate whether the addition of chronic pharmacological β ₂AR stimulation enhances the therapeutic effects of β ₁AR blockade on cardiac remodeling in the same model. Methods and Results. Metoprolol, a β ₁AR blocker, given alone (β ₁) or in combination with β ₂AR agonist, fenoterol (β ₁β ₂) were administered to rats via drinking water for 6 weeks, beginning 2 weeks following permanent coronary ligation. Progressive left ventricular (LV) remodeling of untreated animals, assessed by repeated echocardiography, occurred during the observation time, i.e., 42% and 25% increases in end-systolic and end-diastolic LV volumes respectively, 27% fall in ejection fraction, and 35% infarct expansion. Pressure-volume loop analyses at 2d and 8th post infarction weeks showed continuous deterioration of systolic and diastolic functions and arterio-ventricular mismatch. Histological evaluation at the end of 8 weeks revealed the MI expansion and hypertrophy of cardiomyocytes. β ₁β ₂ prevented LV remodeling, MI expansion and cardiomyocytes hypertrophy to a greater degree than β ₁, due, in large part, to a vasodilatory effect of β ₂AR stimulation and thus improvement of arterio-ventricular mismatch. The abnormal diastolic performance improved only in β ₁β ₂. β ₁β ₂ treatment reduced myocardial apoptosis throughout myocardium, but β ₁ reduced apoptopsis only in the areas remote from MI. Conclusion. The therapeutic effects of chronic β ₁AR blockade on cardiac remodeling of heart failure are enhanced and extended when supplemented with β ₂AR stimulation. This research was supported by the Intramural Research Program of the National Institute on Aging, NIH.     

The “Short‐Coupled” Variant of Right Ventricular Outflow Ventricular Tachycardia: A Not‐So‐Benign Form of Benign Ventricular Tachycardia?

Idiopathic ventricular tachycardia (VT) originating from the right ventricular outflow tract (RVOT-VT) and idiopathic RVOT-extrasystoles are generally considered benign arrhythmias. We described three cases who originally presented with typical "benign looking" RVOT-extrasystoles or RVOT-VT but developed malignant polymorphic VT during follow-up. The unusual aspect of their RVOT-extrasystoles was their coupling interval, which appears to be intermediate between the ultra-short coupling interval of idiopathic VF and the long coupling interval seen in the truly benign RVOT-VT.     

Diastolic dysfunction and arrhythmias caused by overexpression of CaMKIIδ<Subscript>C</Subscript> can be reversed by inhibition of late Na<Superscript>+</Superscript> current

Transgenic (TG) Ca²⁺/calmodulin-dependent protein kinase II (CaMKII) δ_C mice develop systolic heart failure (HF). CaMKII regulates intracellular Ca²⁺ handling proteins as well as sarcolemmal Na⁺ channels. We hypothesized that CaMKII also contributes to diastolic dysfunction and arrhythmias via augmentation of the late Na⁺ current (late I _Na) in early HF (8-week-old TG mice). Echocardiography revealed severe diastolic dysfunction in addition to decreased systolic ejection fraction. Premature arrhythmogenic contractions (PACs) in isolated isometrically twitching papillary muscles only occurred in TG preparations (5 vs. 0, P < 0.05) which could be completely terminated when treated with the late I _Na inhibitor ranolazine (Ran, 5 μmol/L). Force–frequency relationships revealed significantly reduced twitch force amplitudes in TG papillary muscles. Most importantly, diastolic tension increased with raising frequencies to a greater extent in TG papillary muscles compared to WT specimen (at 10 Hz: 3.7 ± 0.4 vs. 2.5 ± 0.3 mN/mm²; P < 0.05). Addition of Ran improved diastolic dysfunction to 2.1 ± 0.2 mN/mm² (at 10 Hz; P < 0.05) without negative inotropic effects. Mechanistically, the late I _Na was markedly elevated in myocytes isolated from TG mice and could be completely reversed by Ran. In conclusion, our results show for the first time that TG CaMKIIδ_C overexpression induces diastolic dysfunction and arrhythmogenic triggers possibly via an enhanced late I _Na. Inhibition of elevated late I _Na had beneficial effects on arrhythmias as well as diastolic function in papillary muscles from CaMKIIδ_C TG mice. Thus, late I _Na inhibition appears to be a promising option for diastolic dysfunction and arrhythmias in HF where CaMKII is found to be increased.     

Impaired response or insufficient dosage?—Examining the potential causes of “inadequate response” to allopurinol in the treatment of gout

Objectives

Gout is one of the most common forms of arthritis. It is well established that urate-lowering therapy that aims for a serum urate less than at least 0.36 mmol/l (6 mg/dl) is required for the successful management of gout. Allopurinol, a xanthine oxidase (XO) inhibitor, is the most commonly used urate-lowering therapy. However, many patients fail to achieve the target serum urate on allopurinol; these patients can be considered to have “inadequate response” to allopurinol. Herein, we examine the potential mechanisms and implications of inadequate response to allopurinol.

Methods

The literature was reviewed for potential causes for failure to reach target serum urate in patients receiving allopurinol.

Results

The two most common causes of inadequate response to allopurinol are poor adherence and under-dosing of allopurinol. Adherent patients who fail to achieve target serum urate on standard doses of allopurinol form a group that could be considered to be “partially resistant” to allopurinol. There are four potential mechanisms for partial allopurinol resistance: decreased conversion of allopurinol to oxypurinol; increased renal excretion of oxypurinol; abnormality in XO structure and/or function such that oxypurinol is rendered less effective and/or drug interactions.

Conclusions

It is important to determine the reasons for failure to achieve treatment targets with allopurinol, particularly as newer agents become available. The knowledge of the mechanisms for inadequate response may help guide the clinician towards making a therapeutic choice that is more likely to result in achieving the serum urate target.