Magnetic resonance imaging of wrist and finger joints in healthy subjects occasionally shows changes resembling erosions and synovitis as seen in rheumatoid arthritis

OBJECTIVE: To explore the presence of changes resembling rheumatoid arthritis erosions and synovitis in metacarpophalangeal (MCP) and wrist joints of healthy individuals on magnetic resonance imaging (MRI) and to compare the MRI findings with conventional radiographic, clinical, and biochemical findings. METHODS: Twenty-eight healthy individuals were studied. Contrast-enhanced MRI and conventional radiography of the dominant wrist and second through fifth MCP joints were performed, coupled with standard clinical assessments and biochemical analyses. MR images were evaluated according to the latest OMERACT (Outcome Measures in Rheumatology Clinical Trials) recommendations with respect to synovitis, erosions, and bone marrow edema. RESULTS: Conventional radiography revealed erosion-like changes in 1 of 224 MCP joint bones (0.4%) and in 1 of 420 wrist joint bones (0.2%). MRI depicted low-grade erosion-like changes in 5 of 224 MCP joint bones (2.2%) and in 7 of 420 wrist joint bones (1.7%), but postcontrast enhancement within the lesion was detected in only 8.3% of these. MRI depicted low-grade synovitis-like changes in 10 of 112 MCP joints (8.9%) and in 8 of 84 assessed wrist areas (9.5%), while only minimal early synovial enhancement was detected by dynamic MRI. Three subjects had elevated serum levels of C-reactive protein, and these subjects displayed 44.5% of the synovitis-like changes and 41.7% of the erosion-like changes. Bone marrow edema-like changes were not found in any joints. CONCLUSION: Changes resembling mild synovitis or small bone erosions are occasionally found in the MCP and wrist joints of healthy controls. Signs of synovitis on dynamic MRI, enhancement within bone erosion-like changes, and signs of bone marrow edema appear rarely or are absent in healthy controls. These signs may thus prove to be very specific in the distinction between arthritic and normal joints.     

Myocardial injury secondary to acute pulmonary embolism - a case report

A case of a 37-year-old male admitted to the hospital due to dyspnea and chest pain is presented. Electrocardiogram showed negative T waves in V1 and V2 as well as subtle ST segment elevation in all precordial leads. Cardiac enzymes were moderately elevated. The initial diagnosis was myocarditis or acute coronary syndrome, however, transthoracic echocardiography showed a marked right ventricular overload which suggested acute pulmonary embolism. The latter diagnosis was confirmed by transesophageal echocardiography which revealed thrombosis of both left and right pulmonary arteries. The patient received thrombolysis and anticoagulants, and his condition improved. He was discharged home and the course of a six-month follow-up was uneventful.     

Shaping Physiological Indices,Swimming Technique,and Their Influence on 200m Breaststroke Race in Young Swimmers

The aim of this study was to investigate somatic properties and physiological capacity, and analyze kinematic parameters in the 200 m breaststroke swimming race. Twenty-seven male swimmers participated in the study. They were 15.7±1.98 years old. Their average height was 1.80 ± 0.02 m and lean body mass (LBM) was 62.45 ± 8.29 kg. Physiological exercise capacity was measured in two separate 90 sec. all-out tests, one for the arms and second for legs. During the tests total work of arm cranking (TWAR) and cycling (TWLG) as well as peak of VO₂ for arm (VO_2peakAR) and leg (VO_2peakLG) were measured. The underwater swimmers body movements were recorded during the all-out swimming 200m breaststroke speed test using an underwater camera installed on a portable trolley. The swimming kinematic parameters and propulsive or non-propulsive movement phases of the arms and legs as well as average speed (V200), surface speed (V200surface) and swimming speed in turn zones (V200turns) were extracted. V200surface was significantly related to the percentage of leg propulsion and was shown to have large effect on VO_2peakLG in the Cohen analysis. V200turns depended significantly on the indicators of physiological performance and body structure: TWAR, VO_2peak LG and LBM, LBM, which in turn strongly determined the measured results of TWAR, TWLG, VO_2peakAR and VO_2peakLG. The V200turns and V200surface were strongly associated with V200, 0.92, p < 0.001 and 0.91, p < 0.001 respectively. In each lap of the 200m swimming there was an increased percentage of propulsion of limb movement observed simultaneously with a reduction in the gliding phase in the breaststroke cycles.

Key points

• This study investigated the influence of the selected indicators of somatic properties and physiological capacity as well kinematic and coordination parameters on breaststroke swimming.
• In this observations the body’s functional capacity have an important impact on achieving good breaststroke swimming results, the V₂₀₀ was moderately associated on VO₂peakLG, moreover, separate V₂₀₀turns depended with VO₂peakLG and on LBM and TWAR.
• The speed of surface breaststroke swimming - V₂₀₀surface similarly as V₂₀₀turns had a very strong influence on the end result of V_{200 ,} 0.91, p<0.001 and 0.92, p<0.001 respectively.
• The ability to swim fast on the surface (V₂₀₀surface) was positively and significantly associated with the percentage time of propulsion generation -LP in the breaststroke cycle.

Key words: Breaststroke swimming, physiological indices, lean body mass, kinematic indices     

Ischemic preconditioning inhibits development of edematous cerulein-induced pancreatitis： Involvement of cyclooxygenases and heat shock protein 70

AIM: To determine whether ischemic preconditioning (IP) affects the development of edematous cerulein-induced pancreatitis and to assess the role of cyclooxygenase-1 (COX-1), COX-2, and heat shock protein 70 (HSP 70) in this process, METHODS: In male Wistar rats, IP was performed by clamping of celiac artery (twice for 5 min at 5-min intervals). Thirty minutes after IP or sham operation, acute pancreatitis was induced by cerulein. Activity of COX-1 or COX-2 was inhibited by resveratrol or rofecoxib, respectively (10 mg/kg). RESULTS: IP significantly reduced pancreatic damage in cerulein-induced pancreatitis as demonstrated by the improvement of pancreas histology, reduction in serum lipase and poly-C ribonuclease activity, and serum concentration of pro-inflammatory interleukin (IL)-lp. Also, IP attenuated the pancreatitis-evoked fall in pancreatic blood flow and pancreatic DNA synthesis. Serum level of anti-inflammatory IL-10 was not affected by IP. Cerulein-induced pancreatitis and IP increased the content of HSP 70 in the pancreas. Maximal increase in HSP 70 was observed when IP was combined with cerulein-induced pancreatitis. Inhibition of COXs, especially COX-2, reduced the protective effect of IP in edematous pancreatitis. CONCLUSION: Our results indicate that IP reduces pancreatic damage in cerulein-induced pancreatitis and this effect, at least in part, depends on the activity of COXs and pancreatic production of HSP 70.     

Association of the ScaI atrial natriuretic peptide gene polymorphism with nonfatal myocardial infarction and extent of coronary artery disease

Background There is growing evidence from recent studies that atrial natriuretic peptide (ANP) plays an important part in coronary blood flow regulation and in atherosclerosis. Transition T2238→C in the atrial natriuretic peptide (ANP) precursor gene, which leads potentially to the translation of ANP with 2 additional arginines, has been suggested to be associated with salt-sensitive hypertension. According to our knowledge, this study is the first to look for the potential association of the ScaI ANP gene polymorphism with the history of nonfatal myocardial infarction and the extent of coronary artery disease (CAD).Methods The study was performed in 847 consecutive, white patients (719 men and 128 women) with significant coronary artery stenosis confirmed by means of elective coronary angiography (at least 1 coronary artery with ≥50% lumen narrowing). Screening for the T2238→C substitution was performed by means of polymerase chain reaction of genomic DNA, followed by ScaI digestion and agarose gel electrophoresis.Results We found a significant association of the A2A2 ScaI ANP genotype with a higher incidence of positive history of nonfatal myocardial infarction (odds ratio 1.85, 95% CI 1.33-2.58) and multiple-vessel CAD (odds ratio 1.45, 95% CI 1.02-2.06). The ScaI ANP genotype distribution did not differ with age, sex, body mass index, plasma lipids, hypertension, diabetes mellitus, and family history of CAD in studied groups.Conclusions Our results suggest that the ScaI ANP polymorphism may be associated with nonfatal myocardial infarction and the extent of CAD. However, the precise mechanism of this association remains to be determined. (Am Heart J 2003;145:125-31.)     

Very small embryonic-like stem cells: characterization, developmental origin, and biological significance

Bone marrow (BM) was, for many years, primarily envisioned as the "home organ" of hematopoietic stem cells (HSC). Augmenting evidence demonstrates, however, that BM, in addition to HSC, also contains a heterogeneous population of non-HSC. Recently, our group identified in BM and other adult tissues a population of very small embryonic-like stem cells (VSELs), which express several markers characteristic for pluripotent stem cells that are characteristic for epiblast/germ line-derived stem cells. Thus, we hypothesize that VSELs are a population of epiblast-derived cells that are deposited during early gastrulation in developing tissues/organs and play an important role in turnover of tissue-specific/committed stem cells. In this context, VSELs deposited in BM can give rise to long-term repopulating HSC. VSELs could be also mobilized into peripheral blood (PB), and the number of these cells circulating in PB increases during stress and tissue/organ injuries. Finally, we envision that in pathological situations VSELs are involved in development of some malignancies (e.g., teratomas, germinal tumors).     

Incidence and risk predictors for osteonecrosis of the jaw in cancer patients treated with intravenous bisphosphonates

Introduction

The aim of this study was to establish the incidence of bisphosphonate-related osteonecrosis of the jaws (BRONJ) in oncologic patients and to determine risk predictors with respect to this condition.

Material and methods

This retrospective review included 197 oncologic patients treated from January 2005 to December 2010 with administration of bisphosphonates (BPs) as part of management. Sex, age, type of cancer diagnosed, period of substantial disease, oral surgery, type of bisphosphonate, number of doses, and cases of BRONJ diagnosis were recorded. The cumulative incidence and incidence rate of BRONJ were calculated. The factors that influenced BRONJ were assessed with multivariate logistic regression and with estimations of 95% confidence intervals and odd ratios. Values of p ≤ 0.05 were considered significant.

Results

The BRONJ appeared in 9.64% of patients. The BRONJ incidence rate was 1 in 28 patients per year of BP treatment. Logistic regression showed that the odds of osteonecrosis increased 1.0172-fold with each given dose of BP. The BRONJ risk with zoledronate was 5-fold higher than that with pamidronate or ibandronate. The risk of BRONJ increased by 40-fold after dental surgery.

Conclusions

Period of BP administration and type of BP used are important risk predictors for the development of BRONJ in oncologic patients treated with intravenous administration of these drugs. Patient-related factors are dental or periodontal events connected with need for oral surgery.     

人类少突胶质细胞在髓鞘修复中的作用

有关髓鞘和少突胶质细胞的研究大部分与脱髓鞘疾病相关,如多发性硬化、脑白质营养不良或脊髓损伤。髓鞘慢性脱失,慢慢导致神经退行性变,最终导致永久而严重的神经功能丧失。因此,尽快恢复髓鞘是修复脱髓鞘疾病的最有效方法。移植外源性的髓鞘再生细胞是一个有希望的治疗方法。已有多项在体和离体实验将各种具有髓鞘形成功能细胞(少突胶质细胞、施万细胞、嗅鞘细胞等)进行移植,观察其髓鞘修复功能。本综述对将人类少突胶质细胞用于治疗脱髓鞘疾病的相关研究进行总结。首先,对人类少突胶质细胞从胚胎发育晚期到产后早期的发育过程进行简要的综述。然后,对各种内源性和外源性的少突胶质细胞调节因子的研究进行总结。在离体实验中,必须调控好各种调节因子才能使培养的少突胶质细胞达到足够的数量用于移植。之后,探讨了人类少突胶质细胞的可能来源,包括一些新型的少突胶质细胞生产策略,如诱导多能干细胞诱导直接分化为少突胶质细胞。最后,本综述对人类少突胶质细胞的髓鞘再生功能和效率进行了系统的回顾。     

Mechanical Properties of Different Nanopatterned TiO2 Substrates and Their Effect on Hydrothermally Synthesized Bioactive Hydroxyapatite Coatings

Nanotechnology is a very attractive tool for tailoring the surface of an orthopedic implant to optimize its interaction with the biological environment. Nanostructured interfaces are promising, especially for orthopedic applications. They can not only improve osseointegration between the implant and the living bone but also may be used as drug delivery platforms. The nanoporous structure can be used as a drug carrier to the surrounding tissue, with the intention to accelerate tissue–implant integration as well as to reduce and treat bacterial infections occurring after implantation. Titanium oxide nanotubes are promising for such applications; however, their brittle nature could be a significantly limiting factor. In this work, we modified the topography of commercially used titanium foil by the anodization process and hydrothermal treatment. As a result, we obtained a crystalline nanoporous u-shaped structure (US) of anodized titanium oxide with improved resistance to scratch compared to TiO₂ nanotubes. The US titanium substrate was successfully modified with hydroxyapatite coating and investigated for bioactivity. Results showed high bioactivity in simulated body fluid (SBF) after two weeks of incubation.     

Strength Properties of a Porous Titanium Alloy Ti6Al4V with Diamond Structure Obtained by Laser Power Bed Fusion (LPBF)

This paper presents the results of experimental research on the strength properties of porous structures with different degrees of density manufactured of Ti6Al4V titanium alloy by Laser Power Bed Fusion. In the experiment, samples with diamond structure of porosity: 34%, 50%, 73% and 81% were used, as well as samples with near-zero porosity. Monotonic tensile tests were carried out to determine the effective values of axial modulus of elasticity, ultimate tensile strength, offset yield strength, ultimate elongation and Poisson ratio for titanium alloys with different porosities. The paper also proposes relationships that can be easily used to estimate the strength and rigidity of a porous material manufactured by 3D printing. They were obtained by the approximation of two quotients. The first one refers to the relationship between the tensile strength of a material with a defined porosity to the strength of full-filled material. The second similarly determines the change in the value of the axial modulus of elasticity. The analysis of microscopic observations of fracture surfaces and also microtomography visualization of the material structure are also presented.