Palaeoproteomic identification of the original binder and modern contaminants in distemper paints from Uvdal stave church, Norway.

Two distemper paint samples taken from decorative boards in Uvdal stave church, Norway, were analysed using palaeoproteomics, with an aim of identifying their binder and possible contaminants. The results point at the use of calfskin to produce hide glue as the original paint binder, and are consistent with the instructions of binder production and resource allocation in the historical records of Norway. Although we did not observe any evidence of prior restoration treatments using protein-based materials, we found abundant traces of human saliva proteins, as well as a few oats and barley peptides, likely deposited together on the boards during their discovery in the 1970s. This work illustrates the need to fully consider contamination sources in palaeoproteomics and to inform those working with such objects about the potential for their contamination.

Metal nanoparticle-induced effects on green toads (Amphibia, Anura) under climate change: conservation implications.

The toxicity of aluminum oxide (Al2O3), copper oxide (CuO), iron oxide (Fe3O4), nickel oxide (NiO), zinc oxide (ZnO), and titanium dioxide (TiO2) nanoparticles (NPs) on amphibians and their interaction with high temperatures, remain unknown. In this study, we investigated the survival, developmental, behavioral, and histological reactions of Bufotes viridis embryos and larvae exposed to different NPs for a duration of 10 days, using lethal concentrations (LC25%, LC50%, and LC75% mg/L) under both ambient (AT: 18 °C) and high (HT: 21 °C) temperatures. Based on LC, NiONPs > ZnONPs > CuONPs > Al2O3NPs > TiO2NPs > Fe3O4NPs showed the highest mortality at AT. A similar pattern was observed at HT, although mortality occurred at lower concentrations and Fe3O4NPs were more toxic than TiO2NPs. The results indicated that increasing concentrations of NPs significantly reduced hatching rates, except for TiO2NPs. Survival rates decreased, abnormality rates increased, and developmental processes slowed down, particularly for NiONPs and ZnONPs, under HT conditions. However, exposure to low concentrations of Fe3O4NPs for up to 7 days, CuONPs for up to 72 h, and NiO, ZnONPs, and TiO2NPs for up to 96 h did not have a negative impact on survival compared with the control group under AT. In behavioral tests with larvae, NPs generally induced hypoactivity at AT and hyperactivity at HT. Histological findings revealed liver and internal gill tissue lesions, and an increase in the number of melanomacrophage centers at HT. These results suggest that global warming may exacerbate the toxicity of metal oxide NPs to amphibians, emphasizing the need for further research and conservation efforts in this context.

Interplay between LncRNA/miRNA and TGF-ß Signaling in the Tumorigenesis of Gynecological Cancer.

Gynecologic cancers are among the most common malignancies with aggressive features and poor prognosis. Tumorigenesis in gynecologic cancers is a complicated process that is influenced by multiple factors, including genetic mutations that activate various oncogenic signaling pathways, including the TGF-ß pathway. Aberrant activation of TGF-ß signaling is correlated with tumor recurrence and metastasis. It has been shown that non-coding RNAs (ncRNAs) have crucial effects on cancer cell proliferation, migration, and metastasis. Upregulation of various ncRNAs, including long non-coding RNAs (lncRNA) and microRNAs (miRNAs), has been reported in several tumors, like cervical, ovarian, and endometrial cancers, but their cellular mechanisms remain to be investigated. Thus, recognizing the role of ncRNAs in regulating the TGF-ß pathway may provide novel strategies for better treatment of cancer patients. The present study summarizes recent findings on the role of ncRNAs in regulating the TGF-ß signaling involved in tumor progression and metastasis in gynecologic cancers.

Marsh frog response to urea fertilizer during the embryonic, larval, and metamorphosis stages: a new perspective into urea toxicity on amphibians.

Amphibian populations are declining worldwide. These declines are caused by a variety of factors, one of which is the use of fertilizers in agriculture. This is especially true for tadpoles, which may develop in fertilizer-polluted agricultural water bodies. Nevertheless, there is little data on the toxicological consequences of fertilizers on amphibians. The goal of this study was to determine the acute and chronic toxicity of urea fertilizer on marsh frogs' (Pelophylax sp.) embryonic, larval, and metamorphic stages. For this purpose, in a static-renewal test, individuals were exposed to twelve nominal concentrations (0 to 15000 mg/L) of urea for 122 days to determine hatching success, survival, growth, development, and metamorphic traits, as well as histological consequences. Based on the results, at concentrations greater than 500 mg/L, no hatching occurred. Survivorship was unaffected for the first 72 hours, but it reached 0% on day 26 at concentrations greater than 150 mg/L. Survival and development rates decreased significantly in 100 and 150 mg/L treatments after a longer duration (day 86). Growth was reduced as well, but it was only significant at 150 mg/L. Metamorphosis time and percentage were significantly impacted, but not metamorphosis size. Increased urea fertilizer concentrations had significant histopathological consequences for the skin, gills, liver, kidneys, and striated muscles. Our results suggest that urea fertilizer, at concentrations commonly found in agroecosystems, may pose a serious threat to temperate anuran species inhabiting these conditions.

Human papillomavirus maybe is a critical player in the regulation of chemoresistance related factors (P53, Rb, TWIST, Bcl-2, Bcl-XL, c-IAP2, cytochrome C, and caspase 3) in breast cancer.

As one of the frequent malignancies, breast cancer (BCa) is the foremost reason for cancer-related deaths among women. The role of Human papillomavirus (HPV) in chemoresistance has rarely been investigated in previous studies. The current study sets out to the possible role of HPV in BCa chemoresistance. In this research, 90 BCa tissue and 33 normal breast tissue were collected. We evaluated the presence of the HPV genome along with the viral (E2, E6, E7) and cellular gene expression associated with cell resistance to death. Statically significant differences in the prevalence of HPV between the BCa group (25.2% or 23/90) and the control group (21.8% or 7/32) were not found. HPV-16 and HPV-18 genotypes were the abundant HPV genotypes. Resistance to the Adriamycin-Cyclophosphamide (AC), paclitaxel regimen was elevated in the HPV- group (56/70) in comparison to the HPV+ group (14/70). Nevertheless, there was no significant difference in the prevalence of resistance to AC + paclitaxel + triple-negative breast cancer combination therapy between the HPV+ group (9/20) and in the HPV- group (11/20). In the BCa group in contrast to the control group, the expression level of Bcl-2, BCL-XL, and c-IAP2 demonstrated a significant decrease, while, the expression level of cytochrome C and caspase 3 was significantly increased. This study suggests that HPV infection might contribute to BCa chemoresistance through disrupt cellular genes involved in cell death.

The anti-cancer effect of chitosan/resveratrol polymeric nanocomplex against triple-negative breast cancer; an in vitro assessment.

Herein, the authors synthesised chitosan nanoparticles (Cs NPs) as a resveratrol (RSV) carrier and evaluated their efficacy in stimulating apoptosis in MDA-MB 231 cells. Blank (Cs NPs) and RSV- Cs NPs (RSV-Cs NPs) were synthesised via ionic gelation and characterised by using fourier-transform infrared spectroscopy (FTIR), Scanning electron microscope, dynamic light scattering/Zeta potential and RSV release. MDA-MB 231 cells were treated with RSV, Cs NPs and RSV-Cs NPs (24, 48, and 72 h), followed by the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay. Cell toxicity was evaluated using lactate dehydrogenase assay, and real-time polymerase chain reaction was performed to explore apoptosis induction. FTIR spectra confirmed the NPs via the formation of cross-linking bonds. Cs and RSV-Cs NPs sizes were about 75 and 198 nm with 14 and 24 mV zeta potentials. The RSV entrapment efficiency was 52.34 ± 0.16%, with an early rapid release followed by a sustained manner. Cs and RSV-Cs NPs inhibited cell proliferation at lower concentrations and IC50 values. RSV-Cs NPs had the most cytotoxic effect and stimulated intrinsic apoptotic pathway, indicated by increased Bcl-2-associated x (BAX), BAX/Bcl-2 ratio, P53 expressions, reduced Bcl-2 and upregulated caspases 3, 8 and 9. RSV-Cs NPs have a great potential to suppress invasive breast cancer cell proliferation by targeting mitochondrial metabolism and inducing the intrinsic apoptotic pathway.

The impact of frame numbers on cardiac ECG-gated SPECT images with interpolated extra frames using echocardiography.

Background: Cardiac echocardiography and cardiac ECG-gated single-photon emission computed tomography (SPECT) are the most common modalities for left ventricle (LV) volumes and function assessment. The temporal resolution of SPECT images is limited and an ECG provides better temporal resolution. This study investigates the impact of frame numbers on images in terms of qualitative and quantitative assessments. Methods: In this study, 5 patients underwent echocardiography and cardiac ECG-gated SPECT imaging, and 5 standard views of the LV were recorded to determine LV walls boundaries and volumes. Also, 2 original images with 8 frames and 16 frames per cardiac cycle were recorded simultaneously in a single gantry orbit. Using the data extracted from the LV model, 8 extra new frames were created with interpolation between existing frames of the original 8-frame image. Three series of images (8 and 16 original and 16 interpolated) were reconstructed separately. LV volumes and ejection fraction (EF) were calculated using Quantitative Gated SPECT (QGS) software. Results: Compared to the original 8-frame gating, original 16-frame gated images resulted in larger end-diastole volume (EDV) (mean ± SD: 68.6 ± 27.11 mL vs 66.2±25.41 mL, p<0.001), smaller end-systole volume (ESV) (mean ± SD: 24.6±8.7 mL vs 26±7.3 mL, p<0.001), and higher EF (64% vs 60.2%, p<0.001). The results for the interpolated series were also different from the original images (closer to the original 16-frame series rather than 8-frame). Conclusion: Changing the frame number from 8 to 16 in cardiac ECG-gated SPECT images caused a significant change in LV volumes and EF. Frame interpolation with sophisticated algorithms can be used to improve the temporal resolution of SPECT images.

Infrared spectroscopic and chemometric approach for identifying binding medium in Sukias mansion's wall paintings.

This paper addresses the application of infrared spectroscopy in combination with chemometrics to identify wall painting's binding medium while employing pattern recognition techniques to process FTIR data-set of complex samples. In this regard, based on the historical documents and previous researches, firstly 56 standard samples were prepared to represent strata of Persian wall paintings in the Safavid period in addition to real historic samples from the case study; Sukias mansion. Then, each sample was analysed by the means of FTIR and chemometrics. Finally, SIMCA was applied to the whole region of studied IR spectra which predicted egg yolk as the binding medium of Sukias mansion samples.

A biophysical study on the mechanism of interactions of DOX or PTX with α-lactalbumin as a delivery carrier.

Doxorubicin and paclitaxel, two hydrophobic chemotherapeutic agents, are used in cancer therapies. Presence of hydrophobic patches and a flexible fold could probably make α-Lactalbumin a suitable carrier for hydrophobic drugs. In the present study, a variety of thermodynamic, spectroscopic, computational, and cellular techniques were applied to assess α-lactalbumin potential as a carrier for doxorubicin and paclitaxel. According to isothermal titration calorimetry data, the interaction between α-lactalbumin and doxorubicin or paclitaxel is spontaneous and the K (M-1) value for the interaction of α-lactalbumin and paclitaxel is higher than that for doxorubicin. Differential scanning calorimetry and anisotropy results indicated formation of α-lactalbumin complexes with doxorubicin or paclitaxel. Furthermore, molecular docking and dynamic studies revealed that TRPs are not involved in α-Lac's interaction with Doxorubicin while TRP 60 interacts with paclitaxel. Based on Pace analysis to determine protein thermal stability, doxorubicin and paclitaxel induced higher and lower thermal stability in α-lactalbumin, respectively. Besides, fluorescence lifetime measurements reflected that the interaction between α-lactalbumin with doxorubicin or paclitaxel was of static nature. Therefore, the authors hypothesized that α-lactalbumin could serve as a carrier for doxorubicin and paclitaxel by reducing cytotoxicity and apoptosis which was demonstrated during our in vitro cell studies.

Effect of Stevia rebaudiana Bertoni extract on sexual dysfunction in Streptozotocin-induced diabetic male rats.

Stevia rebaudiana Bertoni has been used locally as a non-calorie sweetener in medicine and diabetic diet which claimed to have aphrodisiac properties, although no scientific data of this function have been reported. The aim of this study was to investigate the effect of S. rebaudiana extract on sexual dysfunction, testosterone levels and number of Leydig cells in Streptozotocin (STZ)-induced diabetic male rats. A total of 28 diabetic male rats were randomly divided into 4 groups: diabetic group without any extract and 3 extract groups (5, 50 and 100 mg/kg). Seven normal control rats were treated with vehicle mount latency and frequency of (ML, MF), intromission latency and frequency (IL, IF), ejaculation latency and frequency of (EL, EF), the mount latency post ejaculation (MPE), the intromission latency post ejaculation (ILE), the intromission frequency post ejaculation (IFE) were recorded during 30 min on days 0, 14, 28. The serum testosterone levels, blood glucose, sex organs weight, number of leydig cells and histology of testicular tissue were measured. The stevia group (5 mg/kg) had a significant (p<0.05) increase in EF and IF. The number of Leydig cells in the diabetic group were significantly (p<0.05) reduced compared to the normal group and diabetic groups with extract (5 and 50 mg/kg). The serum testosterone levels and other sexual behaviors did not show any significant differences. The low- dose stevia extract with attention to antioxidant, vasodilator and anti-diabetic properties can be aphrodisiac in STZ- induced diabetic male rats.

Biochemical and Histopathological Evidence on Beneficial Effects of Standardized Extract from Tragopogon graminifolius as a Dietary Supplement in Fatty Liver: Role of Oxidative Stress.

Nonalcoholic fatty liver disease (FLD) is a worldwide common liver disorder. Tragopogon graminifolius is used as a dietary supplement for liver disorders. This study aimed to assess the beneficial effects of a standardized preparation from T. graminifolius extract (TGE) in animal model of FLD induced by high-fat diet (HFD). The standardization of TGE based on phenolic compounds was performed using high-performance liquid chromatography (HPLC) analysis. The HFD induced metabolic and hepatic damages. TGE significantly reduced the elevations of serum triglyceride, cholesterol, low-density lipoprotein (LDL), and hepatic enzymes (p =.001 for 25, 50, and 100 mg/kg of TGE). Histopathological studies also confirmed beneficial effects of TGE in FLD. Activity of total antioxidant power, content of total thiol, myeloperoxidase (MPO) enzyme activity, and lipid peroxidation were significantly improved (p <.001). Dietary supplementation with TGE results in improvement of biochemical as well as histopathological parameters. Clinical trials are warranted to prove its efficacy and tolerability in patients with FLD.

Left ventricular torsional parameters before and after atrial fibrillation ablation: a velocity vector imaging study.

BACKGROUND AND AIM: Effects of atrial fibrillation (AF) and its ablative treatment on LV torsion have not yet been fully investigated. This study aimed to examine whether AF patterns of LV contraction and its ablative correction can exert a significant impact on LV torsion by velocity vector imaging (VVI). METHODS: This case-control study conducted in Rajaie Cardiovascular, Medical and Research Center between October 2012 and June 2013. Study participants were 30 consecutive patients with symptomatic paroxysmal AF who met the inclusion criteria. The control group included 24 healthy participants with no history of cardiovascular disease. All individuals were in sinus rhythm at the time of echocardiography before and after the ablation procedure. Two-dimensional (2D) and Doppler echocardiography on a commercially available ultrasound system was performed for all the patients. Scanning was done by a wide-band ultrasound transducer with the frequency range between 2.5-3.5 MHz. The two short-axis views at basal and apical levels were subsequently processed off-line by VVI XStrain software. In order for data analysis, SPSS 16 utilized using paired and independent t-test. p-value ≤0.05 was considered significant. RESULTS: LV torsion (°/cm) mean ± SD was significantly lower in paroxysmal AF patients before ablation (0.8±0.3) than the control group (1.5±0.4) (p<0.001) and increased significantly after ablation (1.1±0.5) compared with before ablation (p=0.004), but still significantly lower than the control group (p=0.003). LV Twist, twist rate and untwist rate mean ± SD were significantly lower in paroxysmal AF patients before ablation than the control group and increased significantly after ablation compared with before ablation, but still significantly lower than the control group. CONCLUSION: Subclinical LV dysfunction may be detected in paroxysmal AF rhythm by measuring torsional parameters through VVI which improves after AF ablation.

Adenovirus-like inclusion body hepatitis in a flock of broiler chickens in Kermanshah province, Iran.

Inclusion body hepatitis (IBH) has been reported in many countries in the world. The IBH or similar cases characterized by hepatitis and presence of intra-nuclear inclusion bodies in hepatocytes have not been reported in broiler chickens in Iran. This is the first report on outbreak of adenovirus-like inclusion body hepatitis in Iran. On October 2012, an onset of high acute mortality in a flock of 2 day-old broiler chickens was reported to the Veterinary Clinic, Faculty of Veterinary Medicine, Razi University, Kermanshah, Iran. The birds showed lethargy, huddling, ruffled feathers, and inappetence. At necropsy the livers were the primary organ affected which were enlarged, pale yellow with necrotic foci and multiple petechial hemorrhages. Tissue samples of liver, kidneys and heart were fixed in 10% buffered formalin. They were processed and stained with hematoxylin and eosin for histopathological studies. Significant microscopic lesions were seen in the livers. Large eosinophilic intra-nuclear inclusion bodies were seen in hepatocytes. Based on the acute high mortality, age of the broilers, gross lesions and histopathological findings (especially intra-nuclear inclusion bodies), the condition was diagnosed as adenovirus-like inclusion body hepatitis.

Diagnostic Pitfalls and Challenges in Interpretation of Heart Transplantation Rejection in Endomyocardial Biopsies With Focus on our Experience.

BACKGROUND: The current trend of heart transplantation in recent years has taken a quantum leap forward. We decided to look back at our experience in this center. OBJECTIVES: Here, we focus on the diagnostic pitfalls and challenges in these biopsies. PATIENTS AND METHODS: Forty two patients based on the standard protocol of heart transplantation group, yielded 63 biopsy samples over a period of 33 months (April 2010 - December 2012). The mean age was 30.4 years (ranging from 16 to 58 years) with 51 males (81%) and 12 females (19%). All the patients were examined periodically and biopsy samples were taken from the right ventricular wall. RESULTS: Rarely fewer than three pieces of myocardial samples were procured. Scar, adipose tissues and blood clots may be seen instead. Quilty effect (nodular endocardial lesions composed of inflammatory cell infiltrates) was seen in 8 cases (12.7%). Other findings not directly related to rejection including early ischemic injury, Quilty effect and post-transplant lymphoproliferative disorders (PTLD) were not encountered. CONCLUSIONS: Specimen inadequacy was not a major problem in our center. It poses a great limitation, because suboptimal specimens sometimes mislead the pathologist. Other findings especially Quilty effect were within the range defined for this finding.

Impact of metabolic syndrome on mortality and morbidity after coronary artery bypass grafting surgery.

BACKGROUND: The prevalence of Metabolic syndrome (MetS) has been increased in Asian countries. It represents a cluster of cardiovascular risk factors including obesity, insulin resistance, lipid abnormality and hypertension. OBJECTIVES: The purpose of this study was to assess the association between MetS and outcome in patients undergoing coronary artery bypass grafting surgery (CABG). PATIENTS AND METHODS: This prospective study was performed on patients scheduled for coronary artery bypass grafting surgery (CABG). All the patients were followed up in hospital and three months afterward. Patients were excluded if they were younger than 18 years or had severe comorbidities, a history of valvular heart disease, and low ejection fraction. RESULTS: A total of 235 patients (135 women) with a mean age of 59 ± 9.3 years were included. MetS was more prevalent in women (P < 0.001). The most prevalent complications were bleeding [20 (8.5%)] and dysrhythmia [18 (7.7%)]. At three months follow-up, the frequency rates of readmission [24 (10.2%)] and mediastinitis [9 (3.8%)] were higher than other complications. Diabetes and MetS were risk factors for a long ICU stay (> 5 days) and atelectasia (P < 0.05). Significant associations were observed between diabetes and pulmonary embolism (P = 0.025) and mediastinitis (P = 0.051). CONCLUSIONS: Identification of MetS before CABG can predict the surgery outcome. Patients with MetS have increased risks for longer ICU stay and atelectasia.

The time interval between the onset of tricuspid E wave and annular Ea wave (TE-Ea) can predict right atrial pressure in patients with heart failure.

OBJECTIVE: There is conflicting data regarding the tricuspid annular velocities and their relation to right ventricular filling pressures. We aimed to assess if the time interval between the onset of tricuspid E wave and annular Ea wave has any correlation with right sided filling pressure in patients with heart failure. METHODS: Thirty heart failure patients (left ventricular ejection fraction≤35%) were enrolled. Echocardiography was performed to obtain tricuspid inflow and tissue Doppler annular velocities just before a standard right heart catheterization. The right atrial pressure was obtained from right heart catheterization. The E/Ea [the ratio of peak velocity of early tricuspid inflow wave (E) to peak velocity of early diastolic wave of the lateral tricuspid annulus (Ea)] and the time intervals between the beginning of R wave of electrocardiogram and onset of E (TE) as well as between the beginning of R wave and onset of Et (TEa) were measured, TE-Ea was calculated as TE-TEa. RESULTS: The mean right atrial pressure (RAP) was 8.8 (SD=4.7) mm Hg. The mean TE-Ea was + 8.61 milliseconds. There was no significant correlation between RAP and E/Ea (r=0.08, p>0.05) but the correlation between TE-Ea and RAP was significant (r=0.5, p=0.01). CONCLUSION: According to our results and in contrary to some prior studies, we showed for the first time that right side TE-Ea stands as a better surrogate of right atrial pressure than E/Ea in heart failure patients. This finding needs more accurate studies and could present TE-Ea as a feasible tool to look into hemodynamics of heart failure patients.

Effect of obesity on mortality and morbidity after coronary artery bypass grafting surgery in Iranian patients.

BACKGROUND: Recent years have witnessed the emergence of obesity as a major public health concern. The drastic rise in obesity and its concomitant co-morbidities is a reflection of the recent changes in dietary habits in Iran and many other developing countries. A recent large population study in Tehran reported that 58% and 75% of middle-aged Iranian men and women, respectively, were either overweight or obese. OBJECTIVES: Considering the impact of obesity on mortality and morbidity after coronary artery bypass graft surgery (CABG), we sought to investigate the association between central obesity and the body mass index (BMI) and the post-CABG mortality and morbidity in Iranian patients. PATIENTS AND METHODS: This prospective study was on 235 adult patients scheduled for isolated CABG in a university hospital. The patients were divided in two groups according to BMI ≥ 30 (obese; n = 60) and BMI < 30 (non-obese; n = 175). In-hospital and late (after 3 months) morbidity and mortality rates were compared between obese and non-obese patients. RESULTS: A total of 235 patients (135 women) with a mean age of 59 ± 9.2 years (range = 29 to 79 years), mean BMI of 27.3 ± 4.2 (range = 17 to 40), and mean waist circumference of 101.2 ± 14.7 cm (range = 55 to 145 cm) were included. By the third postoperative month, wound infection had significantly increased in patients with BMI ≥ 30 (P = 0.022). In-hospital and late morbidity and mortality rates were comparable between the two groups (P > 0.05). CONCLUSIONS: In our patients obesity was a risk factor for wound infection but not atelectasis or the need for intra-aortic balloon pump or re-exploration. Obesity was not associated with increased in-hospital or 3 months mortality rates after CABG.

When one plus one does not equal two: fluorescence anisotropy in aggregates and multiply labeled proteins.

The behavior of fluorescence anisotropy and polarization in systems with multiple dyes is well known. Homo-FRET and its consequent energy migration cause the fluorescence anisotropy to decrease as the number of like fluorophores within energy transfer distance increases. This behavior is well understood when all subunits within a cluster are saturated with fluorophores. However, incomplete labeling as might occur from a mixture of endogenous and labeled monomer units, incomplete saturation of binding sites, or photobleaching produces stochastic mixtures. Models in widespread and longstanding use that describe these mixtures apply an assumption of equal fluorescence efficiency for all sites first stated by Weber and Daniel in 1966. The assumption states that fluorophores have the same brightness when free in solution as they do in close proximity to each other in a cluster. The assumption simplifies descriptions of anisotropy trends as the fractional labeling of the cluster changes. However, fluorophores in close proximity often exhibit nonadditivity due to such things as self-quenching behavior or exciplex formation. Therefore, the anisotropy of stochastic mixtures of fluorophore clusters of a particular size will depend on the behavior of those fluorophores in clusters. We present analytical expressions for fractionally labeled clusters exhibiting a range of behaviors, and experimental results from two systems: an assembled tetrameric cluster of fluorescent proteins and stochastically labeled bovine serum albumin containing up to 24 fluorophores. The experimental results indicate that clustered species do not follow the assumption of equal fluorescence efficiency in the systems studied with clustered fluorophores showing reduced fluorescence intensity. Application of the assumption of equal fluorescence efficiency will underpredict anisotropy and consequently underestimate cluster size in these two cases. The theoretical results indicate that careful selection of the fractional labeling in strongly quenched systems will enhance opportunities to determine cluster sizes, making accessible larger clusters than are currently considered possible.

A rare case of community-acquired native quadruple-valve endocarditis.

We report the case of a male patient with community-acquired quadruple-valve endocarditis on presumed normal native valves. This patient had originally presented elsewhere with generalized edema and malaise and had been diagnosed with suspicious endocarditis and renal dysfunction, for which he unfortunately received incomplete treatment. Transthoracic and transesophageal echocardiographic examinations confirmed quadruple-valve endocarditis and ventricular septal defect.

Assessment of subclinical left ventricular dysfunction in patients with chronic mitral regurgitation using torsional parameters described by tissue Doppler imaging.

BACKGROUND: Left ventricular (LV) twist is due to oppositely directed apical and basal rotation and has been proposed as a sensitive marker of LV function. We sought to assess the impact of chronic pure mitral regurgitation (MR) on the torsional mechanics of the left human ventricle using tissue Doppler imaging. METHODS: Nineteen severe MR patients with a normal LV ejection fraction and 16 non-MR controls underwent conventional echocardiography and apical and basal short-axis color Doppler myocardial imaging (CDMI). LV rotation at the apical and basal short-axis levels was calculated from the averaged tangential velocities of the septal and lateral regions, corrected for the LV radius over time. LV twist was defined as the difference in LV rotation between the two levels, and the LV twist and twisting/untwisting rate profiles were analyzed throughout the cardiac cycle. RESULTS: LV twist and LV torsion were significantly lower in the MR group than in the non-MR group (10.38° ± 4.04° vs. 13.95° ± 4.27°; p value = 0.020; and 1.29 ± 0.54 °/cm vs. 1.76 ± 0.56 °/cm; p value = 0.021, respectively), both suggesting incipient LV dysfunction in the MR group. Similarly, the untwisting rate was lower in the MR group (-79.74 ± 35.97 °/s vs.-110.96 ± 34.65 °/s; p value = 0.020), but there was statistically no significant difference in the LV twist rate. CONCLUSION: The evaluation of LV torsional parameters in MR patients with a normal LV ejection fraction suggests the potential role of these sensitive variables in assessing the early signs of ventricular dysfunction in asymptomatic patients.