Saturated buffers: Improvements and issues

Saturated buffers are a newly developed agricultural best management practice used to redirect tile flow away from waterways, thereby mitigating nutrient losses and downstream eutrophication. This study evaluated the potential benefits of a novel saturated buffer design, which included pitchfork-shaped (PF) dispersion lines and a backflow check valve, that was installed alongside a traditional or standard (ST) buffer on a field in Moultrie County, Illinois, in the spring of 2019. Daily flow measurements and routine water samples were used to monitor the movement of water through both buffers and estimate nutrient loads. During observation days in 2020 and 2021, the PF buffer diverted 35% and 1.9% of incoming tile flow, respectively, while the ST buffer increased effluent rates by 116% and 137% over the same period. Both the PF and ST buffers experienced backflow from 30% to 47% of the monitoring period, well above the often reported 5%. Ultimately, the efficacy of saturated buffers could be improved with minimal, low-cost additions to their designs. Check valves are a simple supplement to saturated buffer design that can enhance flow diversion and potential nutrient removal. Added dispersion lines provide more opportunity for diversion of tile flow; however, they require more land to be removed from agricultural production and could increase backflow volumes, so the costs and benefits should be weighed.

Investigating the impacts of airborne dust on herbicide performance on Amaranthus retroflexus

Dust pollution poses environmental hazards, affecting agriculture through reduced sunlight exposure, photosynthesis, crop yields, and food security. This study explores the interference of dust pollution on herbicide efficacy to control weeds in a semi-arid region. In a factorial experiment conducted in 2019 and replicated in 2020, the interaction of dust and various herbicide applications, including bentazon, sulfosulfuron, tribenuron-methyl, aminopyralid + florasulam, foramsulfuron + iodosulfuron + thiencarbazone, 2,4-D + MCPA, and acetochlor, in controlling Amaranthus retroflexus L. were assessed. Dust induced a 9.2% reduction in the total chlorophyll content of A. retroflexus, while herbicide application independently led to a 67.5% decrease. Contrary to expectations, herbicides performed better in dust, except bentazon, which caused a 28% drop in plant height and a 29% decrease in total biomass compared to non-dust conditions. Both herbicides and dust exerted suppressive effects on A. retroflexus's leaf and stem weights and overall biomass. Despite dust presence, tribenuron-methyl (95.8%), aminopyralid + florasulam (95.7%), sulfosulfuron (96.5%), and foramsulfuron + iodosulfuron + thiencarbazone (97.8%) effectively controlled A. retroflexus. These findings indicate that dust's effect on herbicide efficacy is herbicide-dependent but except bentazon, dust generally increased herbicide efficacy and amplified the control of A. retroflexus.

Co-inoculation of mycorrhizal fungi and plant growth-promoting rhizobacteria improve growth, biochemical and physiological attributes in Dracocephalum kotschyi Boiss. under water deficit stress

Background

Because of swift climate change, drought is a primary environmental factor that substantially diminishes plant productivity. Furthermore, the increased use of chemical fertilizers has given rise to numerous environmental problems and health risks. Presently, there is a transition towards biofertilizers to enhance crops' yield, encompassing medicinal and aromatic varieties.

Methods

This study aimed to explore the impacts of plant growth-promoting rhizobacteria (PGPR), both independently and in conjunction with arbuscular mycorrhizal fungi (AMF), on various morphological, physiological, and phytochemical characteristics of Dracocephalum kotschyi Boiss. This experimentation took place under different irrigation conditions. The irrigation schemes encompassed well watering (WW), mild water stress (MWS), and severe water stress (SWS). The study evaluated the effects of various biofertilizers, including AMF, PGPR, and the combined application of both AMF and PGPR (AMF + PGPR), compared to a control group where no biofertilizers were applied.

Results

The findings of the study revealed that under water-stress conditions, the dry yield and relative water content of D. kotschyi Boiss. experienced a decline. However, the application of AMF, PGPR, and AMF + PGPR led to an enhancement in dry yield and relative water content compared to the control group. Among the treatments, the co-application of AMF and PGPR in plants subjected to well watering (WW) exhibited the tallest growth (65 cm), the highest leaf count (187), and the most elevated chlorophyll a (0.59 mg g-1 fw) and b (0.24 mg g-1 fw) content. Regarding essential oil production, the maximum content (1.29%) and yield (0.13 g plant -1) were obtained from mild water stress (MWS) treatment. The co-application of AMF and PGPR resulted in the highest essential oil content and yield (1.31% and 0.15 g plant-1, respectively). The analysis of D. kotschyi Boiss. essential oil identified twenty-six compounds, with major constituents including geranyl acetate (11.4-18.88%), alpha-pinene (9.33-15.08%), Bis (2-Ethylhexyl) phthalate (8.43-12.8%), neral (6.80-9.32%), geranial (9.23-11.91%), and limonene (5.56-9.12%). Notably, the highest content of geranyl acetate, geranial, limonene, and alpha-pinene was observed in plants subjected to MWS treatment following AMF + PGPR application. Furthermore, the co-application of AMF, PGPR, and severe water stress (SWS) notably increased the total soluble sugar (TSS) and proline content. In conclusion, the results indicate that the combined application of AMF and PGPR can effectively enhance the quantity and quality of essential oil in D. kotschyi Boiss., particularly when the plants are exposed to water deficit stress conditions.

Continuous no-till decreased soil nitrous oxide emissions during corn years after 48 and 50 years in a poorly-drained Alfisol

The soil quality benefits from switching from chisel-disk (CD) operations to continuous no-till (NT) in corn (Zea mays L.) and soybean (Glycine max L.) rotations have been proven over time; but to mitigate climate change, effects of continuous NT on nitrous oxide (N2O) emissions must be evaluated. The objectives of this study were to determine the influence of contrasting tillage practices (CD vs. NT) on soil N2O emissions, soil nitrogen (N) dynamics, corn grain yields, N removals and partial N balances, soil volumetric water content (VWC) and soil temperature following 48 and 50 years of tillage implementation in a long-term corn-soybean rotation experiment in a poorly-drained Alfisol. A four-time replicated randomized complete block design was conducted with tillage treatments [CD (grower's current practice) and NT] as main plots and fertility [a no-fertilizer control (CTR) and fertilizing corn N, P, and K (NPK)] as subplots. Corn grain yield, N removal, and partial N balances were greater in CD than NT in 2018 but not in 2020. Soil N2O-N was similar among tillage treatments in 2018 (3.2 kg N2O-N ha-1) but higher in CD (8.5 kg N2O-N ha-1) than in NT (6.2 kg N2O-N ha-1) in 2020. The CD treatment had higher two-yr cumulative N2O-N emissions (11.9 kg N2O-N ha-1) than NT (9.1 kg N2O-N ha-1), indicating that NT has a potential for reducing N2O-N in poorly-drained Alfisols. Grain yield-scaled N2O-N was lower in NT than CD in 2020 but not in 2018. Soil N2O emissions were positively associated with soil NO3-N, partial N balances, and corn grain yield and negatively associated with soil bulk density and temperature. We concluded that after 48 and 50 years, continuous NT can maintain corn grain yield and mitigate N2O-N emissions indicating to mitigate climate change and increase multi-sphere benefits, continuous NT practices should be implemented.

Arbuscular mycorrhizal Fungi and Changes in Primary and Secondary Metabolites

Medicinal and aromatic plants (MAPs) are able to synthesize a diverse group of secondary metabolites (SMs) such as terpenoids or terpenes, steroids, phenolics, and alkaloids with a broad range of therapeutic and pharmacological potentials. Extensive use of MAPs in various industries makes it important to re-evaluate their research, development, production, and use. In intensive agricultural systems, increasing plant productivity is highly dependent on the application of chemical inputs. Extreme use of chemical or synthetic fertilizers, especially higher doses of N fertilization, decrease the yield of bioactive compounds in MAPs. The plant-soil microbial interaction is an eco-friendly strategy to decrease the demand of chemical fertilizers. Arbuscular mycorrhizal fungi (AMF), belongs to phylum Glomeromycota, can form mutualistic symbiotic associations with more than 80% of plant species. The AMF-plant symbiotic association, in addition to increasing nutrient and water uptake, reprograms the metabolic pathways of plants and changes the concentration of primary and secondary metabolites of medicinal and aromatic plants. The major findings reported that inoculation of AMF with MAPs enhanced secondary metabolites directly by increasing nutrient and water uptake and also improving photosynthesis capacity or indirectly by stimulating SMs' biosynthetic pathways through changes in phytohormonal concentrations and production of signaling molecules. Overall, the AMF-MAPs symbiotic association can be used as new eco-friendly technologies in sustainable agricultural systems for improving the quantity and quality of MAPs.

Co-Application of TiO2 Nanoparticles and Arbuscular Mycorrhizal Fungi Improves Essential Oil Quantity and Quality of Sage (Salvia officinalis L.) in Drought Stress Conditions

Drought stress is known as a major yield-limiting factor in crop production that threatens food security worldwide. Arbuscular mycorrhizal fungi (AMF) and titanium dioxide (TiO₂) have shown to alleviate the effects of drought stress on plants, but information regarding their co-addition to minimize the effects of drought stress on plants is scant. Here, a two-year field experiment was conducted in 2019 and 2020 to evaluate the influence of different irrigation regimes and fertilizer sources on the EO quantity and quality of sage (Salvia officinalis L.). The experiment was laid out as a split plot arranged in a randomized complete block design with three replicates. The irrigation treatments were 25, 50, and 75% maximum allowable depletion (MAD) percentage of the soil available water as non-stress (MAD₂₅), moderate (MAD₅₀), and severe (MAD₇₅) water stress, respectively. Subplots were four fertilizer sources including no-fertilizer control, TiO₂ nanoparticles (100 mg L^-1), AMF inoculation, and co-addition of TiO₂ and AMF (TiO₂ + AMF). Moderate and severe drought stress decreased sage dry matter yield (DMY) by 30 and 65%, respectively. In contrast, application of TiO₂ + AMF increased DMY and water use efficiency (WUE) by 35 and 35%, respectively, compared to the unfertilized treatment. The highest EO content (1.483%), yield (2.52 g m^-2), and cis-thujone (35.84%, main EO constituent of sage) was obtained in MAD₅₀ fertilized with TiO₂ + AMF. In addition, the net income index increased by 44, 47, and 76% with application of TiO₂ nanoparticles, AMF, and co-addition of TiO₂ + AMF, respectively. Overall, the integrative application of the biofertilizer and nanoparticles (TiO₂ + AMF) can be recommended as a sustainable strategy for increasing net income and improving EO productivity and quality of sage plants in drought stress conditions. Future policy discussions should focus on incentivizing growers for replacing synthetic fertilizers with proven nano and biofertilizers to reduce environmental footprints and enhance the sustainability of sage production, especially in drought conditions.

Infective endocarditis in adult patients with congenital heart disease: results from the ESC EORP EURO-ENDO registry

Background

Congenital Heart Disease (CHD) predisposes to Infective Endocarditis (IE)

Purpose

To characterize and to determine the prognosis of IE in this specific population.

Methods

The ESC EORP EURO-ENDO study is a prospective international study in patients (n=3111) diagnosed with IE. In this pre-specified ancillary analysis, we aimed to describe adult patients with CHD (n=365, 11·7%) and compare them with patients without CHD (non-CHD, n=2746) in terms of baseline characteristics and 1-year outcome.

Results

CHD patients (73% men, age 44·8±16·6 years) were younger and had less comorbidities. Of the CHD patients, 14% had a dental procedure in the 6 months before hospitalization versus 7% in non-CHD patients (p<0·001) and more often positive blood cultures for Streptococcus viridans (16·4% vs 8·8%, p<0·001). As in non-CHD patients, IE affected most often the left-sided valves. For CHD patients, in-hospital mortality was 9·0% vs 18·1% in non-CHD patients (p<0·001), and also 1-year outcome was more favourable (log-rank for all-cause mortality p<0·0001), even after adjustment for age (Hazard Ratio (HR) 0·61; 95% CI 0·45–0·81). Within the CHD population, multivariable Cox regression revealed the following predictors for mortality: fistula (HR 6·97), cerebral embolus (HR 4·64), renal insufficiency (HR 3·44), Staphylococcus aureus as causative agent (HR 2·06) and failure to undertake surgery when indicated (HR 5·93).

Conclusion

CHD patients with IE have better outcome in terms of all-cause mortality. The observed high incidence of dental procedures prior to IE fuels the discussion about the need for antibiotic prophylaxis.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): Since the start of EORP, the following companies have supported the program: Abbott Vascular Int. (2011–2021), Amgen Cardiovascular (2009–2018), AstraZeneca (2014–2021), Bayer AG (2009–2018), Boehringer Ingelheim (2009–2019), Boston Scientific (2009–2012), The Bristol Myers Squibb and Pfizer Alliance (2011–2019), Daiichi Sankyo Europe GmbH (2011–2020), The Alliance Daiichi Sankyo Europe GmbH and Eli Lilly and Company (2014–2017), Edwards (2016–2019), Gedeon Richter Plc. (2014–2016), Menarini Int. Op. (2009–2012), MSD-Merck & Co. (2011–2014), Novartis Pharma AG (2014–2020), ResMed (2014–2016), Sanofi (2009–2011), Servier (2009–2021), Vifor (2019–2022). Survival CHD vs non-CHD patients

Impact of the Iranian Registry of Infective Endocarditis (IRIE) and multidisciplinary team approach on patient management

BACKGROUNDS

The last 30 years have witnessed major improvements in understanding of all aspects of infective endocarditis (IE). The Iranian Registry of Infective Endocarditis (IRIE) was formed to address epidemiological aspects of IE vis-à-vis its main pathogens and underlying heart diseases over a 12-year period. Indeed, a multidisciplinary team (MDT) for IE was developed alongside.

METHODS

In a longitudinal observational study, data of adult patients with definite or possible IE based on modified Duke criteria were collected from 2007 to 2016 in our tertiary centre, Iran. From 2016 until 2019, we run a prospective observational study using formation of an IE MDT to provide better patient management and compared data before and after this.

RESULTS

Totally, 645 patients with mean age of 48 ± 17 years were enrolled. Data of 445 and 200 patients were compared before and after IRIE and MDT formation, respectively. We found significantly reduced type and number of applied antibiotics (p = 0.04) and higher rate of positive blood culture (p = 0.001). Hospital length of stay increased significantly after formation of the IRIE and IE MDT (p = 0.02). The rate of heart failure, new abscess formation and cerebral emboli were significantly decreased after IRIE and IE MDT (p < 0.001) and consequently in-hospital mortality reduced significantly (p = 0.05).

CONCLUSION

Developing national registries and MDTs has potential to enhance patient management and reduce IE burden. Our results demonstrated that establishment of the Iranian IRIE and IE MDT conferred better diagnoses, standardised treatments and significantly reduced cardiac and extra cardiac morbidity.

Comparison between cheatham-platinum stent and self-expandable uncovered nitinol stent in patients with coarctation of aorta – a randomized controlled trial

Background

Endovascular treatment is considered the main therapeutic approach for native coarctation of aorta (CoA) in adult patients. Balloon-expandable stents (BE) have been introduced as the primary choice for coarctoplasty. However during the recent years, self-expandable (SE) stents with acceptable radial force have been suggested as an alternative. Still, no randomized controlled (RCT) trials have compared the efficacy and safety of both strategies.

Methods

The present study is a prospective, single center, parallel-group, open-label RCT on patients with native CoA (Figure). Patients were randomized into Bare Cheatham-Platinum Stents and Uncovered Nitinol Stent (SE). All patients were scheduled to be followed in 1-, 6-, 12-month and 36-month intervals. The present report, focuses on the one-year outcome of the study.

Results

Of 101 patients with native CoA referred to our center, 93 patients have been randomized into BE- (47 patients) and SE-arm (46 patients). One year follow up is scheduled to be completed on March 2020. In the preliminary analysis of 62 patients, 1 intraprocedural stent migration has occurred in each group. No aortic perforation was detected in the study. Vascular access site complications were similar between the two groups (3 (6.3%) in BE versus 1 (2.1%) in SE, p value= 0.432). One nonfatal stroke occurred in BE group. No mortality or bailout surgical repair happened in one year study in the two groups. One patient with re-coarctations were detected during one year follow up in each of the groups (p value=0.210). No aortic pseudoaneurysm or aneurysmal formation were observed in 12-month follow up aortic CT angiography.

Conclusion

The preliminary results showed no significant difference in efficacy and safety of both treatment modalities. The final result is pending.

Study Flow Chart

Funding Acknowledgement

Type of funding source: None

3D right ventricular ejection fraction and longitudinal strain are independent predictors of major adverse cardiovascular events in patients with rrhythmogenic right ventricular cardiomyopathy

Introduction

Evaluation of right ventricular (RV) function is essential in the follow up of patients with arrhythmogenic right ventricular cardiomyopathy (ARVC). Role of advance echocardiography including 3D transthoracic echocardiography (3DTTE) for evaluation of 3D RV function and RV longitudinal strain in predicting prognosis in ARVC patients, has not been well investigated.

Purpose

We aimed to evaluate 3DTTE parameters in predicting major advance cardiovascular events (MACE) defined as ventricular arrhythmia, cardiac hospitalization, heart transplantation, and death in ARVC patients.

Methods

Forty-eight definite ARVC subjects based on the 2010 Task force criteria were evaluated with standard 2D transthoracic echocardiography (2DTTE) and 3DTTE. Patients with poor image quality were excluded. RV function was evaluated by 2D and 3D TTE including: fractional area change (FAC), RV global and free wall longitudinal strain (RV2DGLS and RV2DFWLS) and 3D RV ejection fraction (RV3DEF), RV global and free wall longitudinal strain (RV3DGLS, and RV3DFWLS). The patients were followed up for a median period of 12 months (6–18 months) to record MACE.

Results

Forty-eight patients with mean age =38.5±14 years; 79.2% male, and mean RV3DEF =30.33%, were included. During the mean follow up 12 months, 12 patients (25%, with mean RV3DEF = 24.8±9%) experienced MACE whereas mean RV3EF in patient without any cardiovascular events during follow up was 34.21±9%. The most common causes of hospitalization were arrhythmia, right-sided heart failure, and RV clot as the following: Ventricular arrhythmia in 7 patients (14.6%, with mean RV3DEF = 29.01±8.82%), RV clot in 2 cases (4.2%, with mean RV3DEF = 20.2%), right-sided heart failure in 3 patients (6.3%, with mean RV3DEF = 16.83±3.6%) that 2 of them (2.1%, with mean RV3DEF = 14.58±0.63) underwent heart transplantation.

Logistic regression analysis revealed RV3DTTE (p-value = 0.03, OR=0.90, CI: 0.82–0.99), RV3DGLS (p-value = 0.05, OR=1.27, CI: 0.99–1.61) and RV3DFWLS (p-value = 0.01, OR=1.29, CI: 1.05–1.59), predicted cardiac adverse events, but there were no significant association between RV2DGLS, RV2DEWLS and FAC with MACE.

Conclusion

RV3DEF, RV3DGLS, and RV3DFWLS were powerful predictors of morbidity and mortality and can be useful as a valuable method in the prediction of major cardiovascular complications in ARVC patients.

Funding Acknowledgement

Type of funding source: None

Water vapor capturing using an array of traveling liquid beads for desalination and water treatment

Growing concern over the scarcity of freshwater motivates the development of compact and economic vapor capture methods for distributed thermal desalination or harvesting of water. We report a study of water vapor condensation on cold liquid beads traveling down a massive array of vertical cotton threads that act as pseudo-superhydrophilic surfaces. These liquid beads form through intrinsic flow instability and offer localized high-curvature surfaces that enhance vapor diffusion toward the liquid surface, a critical rate-limiting step. As the liquid flow rate increases, the bead spacing decreases, whereas the bead size and speed stay nearly constant. The resulting increase in the spatial bead density leads to mass transfer conductances and hence condensation rates per volume that are almost three times higher than the best reported values. Parallel and contiguous gas flow paths also result in a substantial reduction in gas pressure drop and hence electric fan power consumption.

Correlating diameter, mechanical and structural properties of poly(l-lactide) fibres from needleless electrospinning

The development and application of nanofibres requires a thorough understanding of the mechanical properties on a single fibre level including respective modelling tools for precise fibre analysis. This work presents a mechanical and morphological study of poly-l-lactide nanofibres developed by needleless electrospinning. Atomic force microscopy (AFM) and micromechanical testing (MMT) were used to characterise the mechanical response of the fibres within a diameter range of 200-1400 nm. Young's moduli E determined by means of both methods are in sound agreement and show a strong increase for thinner fibres below a critical diameter of 800 nm. Similar increasing trends for yield stress and hardening modulus were measured by MMT. Finite element analyses show that the common practice of modelling three-point bending tests with either double supported or double clamped beams is prone to significant bias in the determined elastic properties, and that the latter is a good approximation only for small diameters. Therefore, an analytical formula based on intermediate boundary conditions is proposed that is valid for the whole tested range of fibre diameters, providing a consistently low error in axial Young's modulus below 10%. The analysis of fibre morphology by differential scanning calorimetry and 2D wide-angle X-ray scattering revealed increasing polymer chains alignment in the amorphous phase and higher crystallinity of fibres for decreasing diameter. The combination of these observations with the mechanical characterisation suggests a linear relationship between Young's modulus and both crystallinity and molecular orientation in the amorphous phase. STATEMENT OF SIGNIFICANCE: Fibrous membranes have rapidly growing use in various applications, each of which comes with specific property requirements. However, the development and production of nanofibre membranes with dedicated mechanical properties is challenging, in particular with techniques suitable for industrial scales such as needleless electrospinning. It is therefore a key step to understand the mechanical and structural characteristics of single nanofibres developed in this process, and to this end, the present work presents changes of internal fibre structure and mechanical properties with diameter, based on dedicated models. Special attention was given to the commonly used models for analyzing Young's modulus of single nanofibers in three-point bending tests, which are shown to be prone to large errors, and an improved robust approach is proposed.

Echocardiographic assessment of myocardial infarction: comparison of a rat model in two strains

The purpose of this study was to induce myocardial infarction (MI) and compare the echocardiographic parameters and mortality ratio of Lewis inbred and Wistar outbred strain before and after the procedure to help choose the best one for MI studies. In this study MI was induced in 46 Lewis and 34 Wistar by occlusion of left anterior descending artery (LAD). Doppler, two-dimensional (2-D) and 2-D guided M-mode images were recorded from parasternal long-axis and parasternal short-axis and apical four-chamber views. The following parameters were acquired. Interventricular septum diastolic and systolic dimension (IVSd, s), diastolic and systolic left ventricular internal diameter (LVIDd, s), diastolic and systolic left ventricular posterior wall dimension (LVPWd, s), ejection fraction (EF), and fractional shortening (FS). The significant changes were observed in systolic IVS, LVID and EF and FS before and after MI and no significant difference was detected between Lewis and Wistar. The high mortality rate of 51% was seen in the procedure, including anesthesia in Lewis compared to 34% in Wistar. As a conclusion the echocardiographic parameters of these two strains were similar, but according to mortality rate and more cardiac anatomic variation in Lewis rats, Wistar is better for MI studies.

Remineralization of artificial enamel lesions by theobromine

OBJECTIVE

This study investigated the remineralization potential of theobromine in comparison to a standard NaF dentifrice.

METHODS

Three tooth blocks were produced from each of 30 teeth. Caries-like lesion was created on each block using acidified gel. A smaller block was cut from each block for baseline scanning electron microscopy imaging and electron-dispersive spectroscopy (EDS) analysis for surface Ca level. A tooth slice was cut from each lesion-bearing block for transverse microradiography (TMR) quantification of baseline mineral loss (Δz) and lesion depth (LD). Then baseline surface microhardness (SMH) of each lesion was measured. The three blocks from each tooth were assigned to three remineralizing agents: (1) artificial saliva; (2) artificial saliva with theobromine (0.0011 mol/l), and (3) NaF toothpaste slurry (0.0789 mol/l F). Remineralization was conducted using a pH cycling model with storage in artificial saliva. After a 28-day cycle, samples were analyzed using EDS, TMR, and SMH. Intragroup comparison of pre- and posttest data was performed using t tests (p < 0.05). Intergroup comparisons were performed by post hoc multistep comparisons (Tukey).

RESULTS

SMH indicated significant (p < 0.01) remineralization only with theobromine (38 ± 32%) and toothpaste (29 ± 16%). With TMR (Δz/lD), theobromine and toothpaste exhibited significantly (p < 0.01) higher mineral gain relative to artificial saliva. With SMH and TMR, remineralization produced by theobromine and toothpaste was not significantly different. With EDS, calcium deposition was significant in all groups, but not significantly different among the groups (theobromine 13 ± 8%, toothpaste 10 ± 5%, and artificial saliva 6 ± 8%).

CONCLUSION

The present study demonstrated that theobromine in an apatite-forming medium can enhance the remineralization potential of the medium.

Evaluation of surgical treatment of developmental dysplasia of hip for avascular necrosis of femoral head in children

Developmental Dysplasia of the Hip (DDH) is a common congenital malformation. Avascular necrosis of femoral head is the major complication of both close and open reduction of the dislocated joint. Aim of this study was to determine the incidence and influencing factors in different types of a vascular necrosis of femoral head, following surgical treatment of developmental dysplasia of hip in 1-7 years patients. In this study, 120 patients aged from 1 to 7 years old with DDH who had been undergone open surgery, entered to the study. All of these patients followed up for at least 1 year. Surgery procedures divided to 4 groups: open reduction, open reduction+salter osteotomy, open reduction+femur shortening and open reduction+salter osteotomy+femur shortening. The presence of Avascular Necrosis (AVN) had been appraised. 27.5% of surgeries performed on male and 72.5 on female patients. 35.0% of DDH cases were unilateral and remaining was bilateral. 36 patients (30%) shows radiologic findings of AVN, although all of them placed at group I of Bucholz-Ogden classification. 40% of group A patients, 25% of group B, 14.3% of group C and 36.4% of group D patients developed this findings. Open reduction of DDH in older children is effective in the management of DDH and if all of the contrivance considered in the surgery, the rate of AVN would be low and mild (at least in short term follow ups).

Predictors of functional improvement among patients with hip fracture at a rehabilitation ward

To determine possible predictors of FIM scores in patients with hip fracture at discharge a prospective cohort study of 117 patients with either DHS or hip arthroplasty admitted to a rehabilitation service was done. They were classified into four subgroups of underweight (BMI < 18.5), normal (18.5 < BMI < 24.9), overweight (25 < BMI < 29.9) and obese (30 < BMI < 35). Functional evaluations using FIM score as well as sitting, standing, walking days and length of stay for each patient were assessed by a highly skilled therapist at rehabilitation admission; discharge and a post discharge follow up. Recovery was significant in terms of motor subscale. No significant correlation was evident between hospitalization and discharge time with respect to cognitive subscale. The study showed only the age and FIM score at hospitalization to be the independent predictors of total FIM score at discharge. Elevated BMI has not adverse effect on FIM gains in patients with hip fractures. Simple surgery methods such as DHS revealed earlier recovery time than complicated procedures.

Accelerated inactivation in a mutant Na(+) channel associated with idiopathic ventricular fibrillation

Idiopathic ventricular fibrillation (IVF) can cause sudden death in both adults and children. One form of IVF (Brugada syndrome), characterized by S-T segment elevation (STE) in the electrocardiogram, has been linked to mutations of SCN5A, the gene encoding the voltage-gated cardiac Na(+) channel. A missense mutation of SCN5A that substitutes glutamine for leucine at codon 567 (L567Q, in the cytoplasmic linker between domains I and II) is identified with sudden infant death and Brugada syndrome in one family. However, neither the functional effect of the L567Q mutation nor the molecular mechanism underlying the pathogenicity of the mutation is known. Patch-clamp analysis of L567Q channels expressed in human embryonic kidney cells revealed a marked acceleration and a negative shift in the voltage dependence of inactivation. Unlike other Brugada mutations, this phenotype was expressed independently of temperature or auxiliary beta(1)-subunits. These results support a proposed linkage between Brugada syndrome and some instances of sudden infant death and the hypothesis that reduced Na(+) conductance is the primary cause of IVF with STE.

Transcriptional activation of the cholesterol 7alpha-hydroxylase gene (CYP7A) by nuclear hormone receptors

The gene encoding cholesterol 7alpha-hydroxylase (CYP7A), the rate-limiting enzyme in bile acid synthesis, is transcriptionally regulated by bile acids and hormones. Previously, we have identified two bile acid response elements (BARE) in the promoter of the CYP7A gene. The BARE II is located in nt -149/-118 region and contains three hormone response element (HRE)-like sequences that form two overlapping nuclear receptor binding sites. One is a direct repeat separated by one nucleotide DR1 (-146- TGGACTtAGTTCA-134) and the other is a direct repeat separated by five nucleotides DR5 (-139-AGTTCAaggccGGG TAA-123). Mutagenesis of these HRE sequences resulted in lower transcriptional activity of the CYP7A promoter/reporter genes in transient transfection assay in HepG2 cells. The orphan nuclear receptor, hepatocyte nuclear factor 4 (HNF-4)1, binds to the DR1 sequence as assessed by electrophoretic mobility shift assay, and activates the CYP7A promoter/reporter activity by about 9-fold. Cotransfection of HNF-4 plasmid with another orphan nuclear receptor, chicken ovalbumin upstream promoter-transcription factor II (COUP-TFII), synergistically activated the CYP7A transcription by 80-fold. The DR5 binds the RXR/RAR heterodimer. A hepatocyte nuclear factor-3 (HNF-3) binding site (-175-TGTTTGTTCT-166) was identified. HNF-3 was required for both basal transcriptional activity and stimulation of the rat CYP7A promoter activity by retinoic acid. Combinatorial interactions and binding of these transcription factors to BAREs may modulate the promoter activity and also mediate bile acid repression of CYP7A gene transcription.

The opposing effects of retinoic acid and phorbol esters converge to a common response element in the promoter of the rat cholesterol 7 alpha-hydroxylase gene (CYP7A)

The activity of the rat CYP7A/luciferase reporter gene was increased five-fold by all-trans retinoic acid (atRA) or 9-cis retinoic acid (9cRA) in transient transfection assay in HepG2 cells. Cotransfection with retinoid X receptor (RXR) stimulated the promoter activity in the absence of ligand, however, addition of atRA inhibited the transcriptional activity. Cotransfection with retinoic acid receptor (RAR) did not have much effect on CYP7A promoter activity. The CYP7A promoter, when linked upstream to the SV40/ luciferase reporter gene, strongly repressed the phorbol 12-myristate 13-acetate (PMA)-stimulated SV40/ luciferase reporter gene activity. The regions conferring the effects of RA and PMA were mapped to nt-176/ -117 and nt-148/-129, respectively. Several direct repeats of hormone response element (AGTTCA) in this region are required for RA response. AP-1 like sequences are located within the region responding to both RA and PMA. Site-directed mutagenesis of the AP-1 site abolished the effects of both RA and phorbol esters. Retinoic acid effect was antagonized by PMA. Moreover, cotransfection of Fos and Jun expression vectors blunted the stimulatory effect of retinoic acid on the CYP7A/luciferase gene activity. Therefore, effects of two different signal transduction pathways converge to a common response element. This regulatory cross-talk may be involved in bile acid repression and regulates CYP7 gene transcription in the liver.

Combined effects of caffeine and alcohol during pregnancy on bones in newborn rats

The combined effects of caffeine and alcohol on mineral contents of fetal mandibles and femurs were studied. Pregnant rats were divided into four groups: group 1, control; group 2, caffeine; group 3, alcohol; and group 4, caffeine-plus-alcohol. Alcohol (1.0 g ethanol/kg body weight) was intubated twice daily, beginning at day 9 of gestation. Caffeine (2 mg/100 g body weight) was given as a dietary supplement. Groups 1 and 2 were intubated with isocaloric sucrose solution. At birth, randomly selected pups were killed and the mandible and femur were removed and dried. Ca, P, Mg, Zn and hydroxyproline in these bones were measured. Notwithstanding the dams' intake of caffeine and alcohol administered separately, the present results suggest that the combination of caffeine and alcohol exhibited the most detrimental effects.