Surface Area Basis Research Articles

Strategy to avoid patient-prosthesis mismatch: aortic root enlargement

The choice of a valve with an effective orifice area matching the body surface area and providing efficient hemodynamics is an important factor affecting mortality and morbidity in patients undergoing aortic valve replacement. Our preventative strategy was to implant a larger prosthetic valve by aortic root enlargement using the Nunez procedure in 17 patients between February 2010 and January 2011. The decision to enlarge the aortic root was taken when the 19-mm sizer could not be negotiated easily through the aortic root, or on the basis of body surface area of the patient or type of prosthesis available. Postoperative reductions in peak and mean pressure gradients across aortic valve of 12.8-16.5 and 10.2-12.6 mm Hg, respectively, were observed. Postoperative effective orifice areas of the aortic valves were 1.1-1.5 cm(2). By upsizing the aortic valve, we were able to eliminate patient-prosthesis mismatch in 5 patients, and reduce severe patient-prosthesis mismatch to moderate in 11. Aortic root enlargement is a safe procedure. Therefore, cardiac surgeons should not be reluctant to enlarge the aortic root with an autologous pericardial patch to permit implantation of an adequate size of aortic valve prosthesis, with minimal additional aortic crossclamp time and no added cost.

Factors influencing antibiotics adsorption onto engineered adsorbents

The study evaluated the adsorption of two antibiotics by four engineered adsorbents (hypercrosslinked resin MN-202, macroporous resin XAD-4, activated carbon F-400, and multi-walled carbon nanotubes (MWCNT)) from aqueous solutions. The dynamic results demonstrated the dominant influence of pore size in adsorption. The adsorption amounts of antibiotics on XAD-4 were attributed to the hydrophobic effect, whereas steric hindrance or micropore-filling played a main role in the adsorption of antibiotics by F-400 because of its high microporosity. Aside from F-400, similar patterns of pH-dependent adsorption were observed, implying the importance of antibiotic molecular forms to the adsorption process for adsorbents. Increasing the ionic concentration with CaCl2 produced particular adsorption characteristics on MWCNT at pH 2.0 and F-400 at pH 8.0, which were attributed to the highly available contact surfaces and molecular sieving, respectively. Its hybrid characteristics incorporating a considerable portion of mesopores and micropores made hypercross linked MN-202 a superior antibiotic adsorbent with high adsorption capacity. Furthermore, the adsorption capacity of MWCNT on the basis of surface area was more advantageous than that of the other adsorbents because MWCNT has a much more compact molecular arrangement.

나노크기 매킨나와이트로 코팅된 알루미나에 의한 아비산염의 제거

나노크기 매킨나와이트(nanocrystalline mackinawite, FeS)는 높은 비표면적을 지닌 반응성 높은 광물로, 오염된 지하수나 토양의 복원을 위해 널리 사용된다. 또한 매킨나와이트는 혐기성 부식반응에 대해 열역학적으로 안정하고, 황산염 환원미생물의 대사에 의해 재생된다는 장점이 있다. 하지만 매킨나와이트 나노입자는 지하수 흐름에 의해 멀리 확산되거나 입자집적이 일어나 대수층 공극을 막는다. 따라서 현장복원을 위한 투과반응벽(permeable reactive barrier)의 설치를 위해서 나노크기 매킨나와이트에 대한 변형이 필요하다. 이를 위해 본 연구에서는 코팅법을 활용해 매킨나와이트 나노입자를 알루미나(alumina, <TEX>$Al_2O_3$</TEX>) 및 활성알루미나(activated alumina) 표면에 증착시켰다. 매킨나와이트의 코팅량은 pH에 따라 현저히 달랐으며, 두 종의 알루미나 모두 약 pH 6.9에서 최대 코팅이 관찰되었다. 이 pH에서 알루미나와 매킨나와이트는 반대의 표면전하(surface charge)를 띠어 두 광물 간 정전기적 인력이 발생하고, 이로 인해 효율적인 코팅이 일어났다. 이 pH에서 알루미나 및 활성 알루미나에 의한 코팅량은 각각 0.038 <TEX>$mmol{\cdot}FeS/g$</TEX>과 0.114 <TEX>$mmol{\cdot}FeS/g$</TEX>이었다. 혐기성 조건에서 코팅되지 않은 알루미나 및 활성 알루미나, 그리고 최적 pH에서 코팅된 알루미나 및 활성 알루미나를 사용해 아비산염(arsenite) 흡착실험을 수행했다. 코팅되지 않은 활성 알루미나는 코팅되지 않은 알루미나와 비교해 단위질량당 높은 아비산염의 제거를 보여주었으나, 매킨나와이트의 코팅에 의한 흡착량 증가를 보이지 않았다. 활성 알루미나는 높은 비표면적을 지니고 있어 반응성 높은 수산화작용기(hydroxyl functional group)가 다수 존재했고, 이로 인해 코팅된 매킨나와이트에 의한 아비산염의 제거가 중요하지 않았다. 반면 알루미나는 매킨나와이트 코팅에 의해 향상된 아비산염의 제거율을 보였는데, 이것은 알루미나에 존재한 수산화작용기가 아비산염과의 표면배위결합(surface complexation)에 소모되고, 코팅된 매킨나와이트에 의한 부가적인 흡착이 일어났기 때문이다. 코팅된 알루미나는 이전에 연구된 코팅된 실리카와 비교해보면 단위 비표면적당 매킨나와이트의 코팅량이 약 8배 높았으며, 더 높은 아비산염에 대한 흡착력을 보였다. 따라서 본 연구의 결과는 코팅된 알루미나는 투과반응벽의 설치에 적합한 물질이고, 특히 아비산염으로 오염된 지하수의 정화에 유용하게 적용될 수 있음을 지시하고 있다. Due to the large specific surface area and great reactivity toward environmental contaminants, nanocrystalline mackinawite (FeS) has been widely applied for the remediation of contaminated groundwater and soil. Furthermore, nanocrystalline FeS is rather thermodynamically stable against anoxic corrosion, and its reactivity can be regenerated continuously by the activity of sulfate-reducing bacteria. However, nanocrystalline mackinawite is prone to either spread out along the groundwater flow or cause pore clogging in aquifers by particle aggregation. Accordingly, this mineral should be modified for the application of permeable reactive barriers (PRBs). In this study, coating methods were investigated by which mackinawite nanoparticles were deposited on the surface of alumina or activated alumina. The amount of FeS coating was found to significantly vary with pH, with the highest amount occurring at pH ~6.9 for both minerals. At this pH, the surfaces of mackinawite and alumina (or activated alumina) were oppositely charged, with the resultant electrostatic attraction making the coating highly effective. At this pH, the coating amounts by alumina and activated alumina were 0.038 and 0.114 <TEX>$mmol{\cdot}FeS/g$</TEX>, respectively. Under anoxic conditions, arsenite sorption experiments were conducted with uncoated alumina, uncoated activated alumina, and both minerals coated with FeS at the optimal pH for comparison of their reactivity. Uncoated activated alumina showed the higher arsenite removal compared to uncoated alumina. Notably, the arsenite sorption capacity of activated alumina was little changed by the coating with FeS. This might be attributed to the abundance of highly reactive hydroxyl functional groups (<TEX>${\equiv}$</TEX>AlOH) on the surface of activated alumina, making the arsenite sorption by the coated FeS unnoticeable. In contrast, the arsenite sorption capacity of alumina was found to increase substantially by the FeS coating. This was due to the consumption of the surface hydroxyl functional groups on the alumina surface and the subsequent occurrence of As(III) sorption by the coated FeS. Alumina, on the surface area basis, has about 8 times higher FeS coating amount and higher As(III) sorption capacity than silica. This study indicates that alumina is a better candidate than silica for the coating of nanocrystalline mackinawite.

The sorption of organic carbon onto differing clay minerals in the presence and absence of hydrous iron oxide

Sorption of organic carbon onto phyllosilicate clays and hydrous iron oxides influences the accumulation and stabilisation of organic carbon in soils. However, the effects of interactions between hydrous iron oxides and phyllosilicate clays on the sorption of dissolved organic carbon (DOC) are poorly understood. We carried out a batch experiment to examine the effects of goethite coatings on kaolinite, illite, and smectite on DOC sorption. The effect of coating illitic clay with different hydrous iron oxides (haematite, goethite, ferrihydrite) on DOC sorption was studied in another experiment. Organic matter extracted from dried medic (Medicago truncatula cv. Praggio) shoot residue was reacted with minerals at DOC concentrations ranging from 0 to 200mgCL−1 at pH6.0. The maximum adsorption capacity (Qmax) of phyllosilicate clays, as determined from fits to the Langmuir equation, increased in the order kaolinite<illite<smectite on a mass basis and illite<smectite<kaolinite on a surface area basis. The sorption capacity of kaolinitic clay increased significantly with goethite coating, whereas the sorption capacity of illitic and smectitic clays was not affected by goethite coating. Ferrihydrite coating increased the sorption capacity of the illitic clays, while haematite coating decreased the sorption capacity; goethite-coated illitic clays had a sorption capacity similar to pure illitic clays. Desorption experiments resulted in the removal of 6–14% of the sorbed DOC. The presence of goethite reduced desorption from kaolinitic clays but did not influence desorption from illitic and smectitic clays. The results suggest that interactions of hydrous iron oxides and phyllosilicate clays can modify DOC sorption and desorption, probably by affecting the surface charges. Therefore, sorption and desorption of organic matter from soils may vary with mineral assemblage, with increasing suppression of the contribution of hydrous oxides at circumneutral to slightly alkaline soil reaction.

2D-ultrasound and endocrinologic evaluation of placentation in early pregnancy and its relationship to fetal birthweight in normal pregnancies and pre-eclampsia

ObjectivesTo study the relationships between 2D ultrasound measurements of placentation and maternal serum (MS) levels of PAPP-A, inhibin A and fβhCG in early pregnancy and subsequent fetal growth in pregnancies with a normal and abnormal outcome. Study designProspective population-based cohort study of 301 pregnancies with a normal outcome, 18 with a pregnancy complicated by pre-term delivery (PTD) and 14 with subsequent pre-eclampsia (PE). Main outcome measuresBasal placental surface area, placental thickness, ellipsivity and volume; MS PAPP-A and fβhCG at 11–13 + 6 weeks, MS inhibin A at 15–22 weeks and birthweight centile at delivery. ResultsIn the normal group, the basal surface area showed a significantly (P < 0.001) positive correlation with placental thickness and placental ellipsivity. With the exception of placental ellipsivity, all other placental ultrasound parameters were significantly related with birthweight centile. Inhibin A showed a significant (P < 0.005) correlation with birthweight centiles. The basal plate surface area and MS PAPP-A were significantly (P < 0.01 and P < 0.001, respectively) lower and MS inhibin A significantly (P < 0.01) higher in PE than in controls. No changes were found in pregnancies complicated by PTD. ConclusionThe basal plate surface area at 11–14 weeks reflects indirectly normal and abnormal placentation and development of the definitive placenta. Combined with MS PAPP-A and/or inhibin A levels this parameter could be useful in identifying from the end of the first trimester, pregnancies subsequently complicated with PE.

Reductive dissolution of goethite and hematite by reduced flavins

The abiotic reductive dissolution of goethite and hematite by the reduced forms of flavin mononucleotide (FMNH2) and riboflavin (RBFH2), electron shuttles secreted by the dissimilatory iron-reducing bacterium Shewanella, was investigated under stringent anaerobic conditions. At pH 7.0, the reductive dissolution rates of goethite were 3.5μmolesm−2h−1 by 50μM FMNH2 and 0.27μmolesm−2h−1 by 50μM RBFH2; the reductive dissolution rates of hematite were 29μmolesm−2h−1 by 50μM FMNH2 and 151μmolesm−2h−1 by 50μM RBFH2. The extent of reaction was limited by the thermodynamic driving force at circumneutral pH. Both the initial reaction rate and reaction extent increased with decreasing pH. On a unit surface area basis, goethite was less reactive than hematite between pH 4.0 and 7.0. AH2DS, the reduced form of the well-studied synthetic electron shuttle anthraquinone-2,6-disulfonate, yielded higher rates than FMNH2 under most reaction conditions. Two additional model compounds, methyl viologen and benzyl viologen, were investigated under similar reaction conditions to explore the relationship between reaction rate and thermodynamic properties. Relevant kinetic data from the literature were also included in the analysis to span a large range in half-cell potentials. Other conditions being equal, the surface area normalized initial reaction rate (ra) increased as the redox potential of the reductant became more negative. A non-linear relationship was observed between logra and the redox potential for eight reductants at pH 7.0. When pH and reductant concentration were fixed, logra was positively correlated to the redox potential of four Fe(III) oxides over a wide pH range, following a non-linear relationship as well.

A UGT1A1 genotype-directed phase II toxicity and efficacy-finding study of irinotecan combined with S-1 as first-line treatment in advanced gastric cancer.

TPS4154 Background: The best chemotherapy regimen for advanced gastric cancer (AGC) is uncertain, but promising findings have been reported with Irinotecan (IRI) plus S-1. However, IRI can induce severe neutropenia or diarrhea associated with homozygosity of the UGT1A1*28 or UGT1A1*6 alleles. This trial was designed to compare the toxicity and efficacy on different doses of IRI combined with S-1 according to UGT1A1 genotype as first-line chemotherapy in AGC in Chinese patients. Methods: Previously untreated patients with histologically proven gastric or gastroesophageal junction adenocarcinoma, aged between 18 and 75 years with ECOG performance status 0-2 were classified according to UGT1A1 genotype: wild-type (none of *28 or *6 allele); heterozygous (only one of *28 or *6 allele); or homozygous (*28/*28, *6/*6, or double heterozygous for *28 and *6). Patients were randomized (1:1) to receive either low or high dose of IRI given i.v. (90 min) on day 1 in each genotype group. The low and high dose of IRI were 80mg/m2 and 200 mg/m2 in the wild-type group, 80 mg/m2 and 150 mg/m2 in the heterozygous group, 40 mg/m2 and 80 mg/m2 in the homozygous group. S-1 was administered orally at a dose level set on the basis of the body surface area (BSA): 40 (BSA&lt;1.25 m2), 50 (BSA≥1.25 to&lt;1.5 m2 ) or 60 mg (BSA≥1.5 m2) twice a day on day1-7. Courses were repeated every 2 weeks, unless disease progression, unacceptable toxicity or patient refusal. The primary endpoint was to explore the safety and efficacy on different doses of IRI combined with S-1 according to UGT1A1 polymorphism. Based on the frequency of UGT1A1*28 and UGT1A1*6 gene polymorphism in Asian gastrointestinal cancer patients, the chi-square test and fisher exact test were used to evaluate the planned sample size which is 100 in total: 40 for the wild-type, 40 for the heterozygous and 20 for the homozygous group. Until now, 8 patients have been enrolled. Clinical trial information: ChiCTR-OCH-12002472.

Iron aluminium mixed pillared montmorillonite and the rare earth exchanged analogues as efficient catalysts for phenol oxidation

Iron aluminium mixed pillared montmorillonite prepared by partial hydrolysis method was exchanged with lanthanum, cerium and thorium metal salts. The pillared montmorillonite shows considerable increase in basal spacing and surface area. 27Al and 29Si nuclear magnetic resonance spectra show the presence of iron substituted Keggin cation as the pillaring species. Energy dispersive X-ray analysis shows the presence of about 2% rare earth metals. The prepared systems are excellent catalysts for hydroxylation of phenol underlining the use of eco-friendly clay catalysts for effective removal of pollutants. A detailed study of reaction variables suggests that oxidation of phenol increases with temperature and maximum conversion is obtained at 90°C. Hydroquinone selectivity increases with phenol concentration and time but decreases with temperature.

Experimentally determined dissolution kinetics of SON68 glass at 90 °C over a silica saturation interval: Evidence against a linear rate law

Flow-through dissolution experiments were carried out on the SON68 glass—the inactive analog of the French high-level waste glass—at 90°C and pH=9 over a silica saturation interval [0–150ppm Si(aq)]. Two types of specimens were subjected to dissolution studies: powders (249–150, 149–75 or 74–45μm diameter size fractions) or monoliths (∼1cm×1cm×4mm). At each Si concentration interval individual coupon and glass powder experiments were run at the same flow-to-surface area (q/S) conditions. Under dilute solution conditions, the dissolution rate becomes independent of q/S and define the forward rate of reaction of 0.30g/(m2d). Dissolution rates of powders normalized on either a geometric or a B.E.T. surface area basis were compared to rates determined on monoliths. In every case, the geometric surface area normalized rates matched those of the monoliths, conclusively showing that B.E.T. normalized rates are too low by a factor of ∼3×. In Si-free solutions changes in flow rates resulted in differences in Al released to solution (∼50 to 3140ppb), correlating inversely with dissolution rates. Si was added to input solutions and kept constant (“direct”), but in select experiments Si concentrations were above target concentrations, and then dropped to their target values (“indirect”). Both “direct” and “indirect” Si addition experiments yielded identical dissolution rates within experimental uncertainty. Progressive addition of Si to the input solution caused a decrease in rates from 0.30 to 0.0020g/(m2d), or a factor of ∼150×, but the decrease is strongly non-linear with respect to Si. These data are inconsistent with simple models relating glass dissolution to the chemical affinity of reaction.

Outdoor Prototype Results for Direct Atmospheric Capture of Carbon Dioxide

At Carbon Engineering, we have built a prototype air contactor with 10 m3 of packing volume, and have absorbed carbon dioxide from ambient air for over 1000hours of outdoor operation. Our prototype was built to: a) test our cross-flow, pulsed-liquid, PVC packing-based contactor design in an operational environment; b) to evaluate fan and liquid pumping energy requirements of our design; c) to assess technical and safety risks involved with liquid solution loss through entrained “drift” droplets, and; d) to examine for packing or solution fouling by atmospheric particulates. In this paper we present our results on the liquid pumping and fan energy requirements of our prototype, and show preliminary analyses we have conducted on liquid loss through “drift” droplets and NPE fouling.Our operation with pulsed liquid flow allows us to fully wet the surface of our structured packing with a brief period of full flow, then to cut flow for a duration of several minutes to let the liquid slowly react away as CO2 is absorbed. Using this technique we have cut average liquid flow to 10% of full manufacturer's specifications while retaining an average of over 80% of the capture rate observed at full flow. This method, under patent application, has allowed us to reduce our mgh fluid pumping energy requirement for the contactor to <40MJ/ton-CO2 (<11 kWh/ton-CO2). Here we report this energy requirement without accounting for pump efficiency, which we nominally assume to be ηpump=90%.Our prototype contactor has utilized high-performance XF12560 structured packing from Brentwood Industries (Reading, PA), manufactured from PVC rather than a stainless-steel. This choice has given us several advantages, chiefly that it costs far less on a per-surface-area basis, and that is provides a much lower pressure drop on a per- surface-area basis. We have previously shown data that suggests these plastic packings absorb CO2 with equal performance to traditional stainless-steel designs once wetted properly [1]. The high-performance and low pressure drop characteristics of our XF12560 product have allowed us to achieve PV work requirements of <350MJ/ton-CO2 (<100 kWh/ton-CO2). Again, this value does not reflect fan efficiency, which we commonly use as ηfan=55% in our analyses. This current value for PV work requirement is higher than we had previously reported, due to a specific cause of under-performance in our prototype which is discussed in this paper. Despite this, we are in fact very encouraged by the results of our first attempt at long-duration outdoor contacting, and we have numerous design improvements stemming from our prototype operation that will be included in the next iteration of our full-scale contactor design.Extensive air sampling was carried out during our contactor operation to measure the loss of liquid solution via “drift” droplets. During normal pulsed-flow contactor operation, 6 hour air samples taken from the contact outflow and measured for our K+ ion tracer, showed OH concentrations to be <5% of the OHSA regulated indoor respiratory requirement. After our 1000hours of integrated CO2 absorption time, we have as of yet been unable to observe any significant performance decrease in the absorptive properties of our working solution or in the efficiency of our structured packing product.

Graphene Nanosheets and Graphite Oxide as Promising Adsorbents for Removal of Organic Contaminants from Aqueous Solution

Graphenes are an emerging class of carbon nanomaterials whose adsorption properties toward organic compounds have not been well understood. In the present study, graphene nanosheets were prepared by reoxidation and abrupt heating of graphite oxide, which was prepared by sequential chemical oxidation of commercial nonporous graphite powder. Adsorption properties of three aromatic compounds (naphthalene, 2-naphthol, and 1-naphthylamine) and one pharmaceutical compound (tylosin) on graphene nanosheets and graphite oxide were examined to explore the potential of these two adsorbents for the removal of organic contaminants from aqueous solutions. Compared with the literature data of adsorption on carbon nanotubes, adsorption of bulky, flexible tylosin on graphene nanosheets exhibited markedly faster adsorption kinetics, which can be attributed to their opened-up layer structure. Graphene nanosheets and graphite oxide showed similar sequences of adsorption affinity: 1-naphthylamine > 2-naphthol > tylosin > naphthalene (with much larger differences observed on graphite oxide). It was proposed that the strong adsorption of the three aromatic compounds was mainly due to π-π electron donor-acceptor interactions with the graphitic surfaces of adsorbents. Additionally, Lewis acid-base interaction was likely an important factor contributing to the strong adsorption of 1-naphthylamine and tylosin, especially for the O-functionality-abundant graphite oxide. After being normalized on the basis of adsorbent surface area, adsorption affinities of all four tested adsorbates on graphene nanosheets were very close to those on nonporous graphite powder, reflecting complete accessibility of the adsorbent surface area in adsorption.

Single and binary adsorption of heavy metals on fly ash samples from aqueous solution

Thousands of toxins are released every day into the environment through numerous industrial operations and this resulted in continuous search for newer adsorbents. Two types of adsorbents, 1:10 fly ash and 1:15 fly ash samples were prepared from coal fired thermal power plant fly ash by treating it with calculated amount of calcium carbonate and phosphoric acid. Adsorbents were characterized on the basis of FTIR, XRF, surface area, pH and particle size studies. Adsorption of Pb(II), Ni(II) and Cr(VI) from single metal solutions on 1:10 fly ash from aqueous solution was carried out as a function of initial metal ion concentration, adsorbent dose, contact time and pH of the solution. Adsorption data obtained was analyzed with Langmuir, Freundlich and Temkin adsorption isotherm equations. Binary adsorption of Pb(II) and Ni(II) was studied on 1:10 and 1:15 fly ash samples as a function of initial metal ion concentration to investigate their efficiencies in removing metal ions from aqueous solution. In the case of 1:10 and 1:15 fly ash samples, Pb(II) and Ni(II) removal was observed to be almost the same. The significant difference observed between single and binary metal adsorption is in the initial metal removal rate. Slightly lower initial metal removal rate observed in the case of binary adsorption is probably due to the presence of competing metal ions in the solution. Fly ash based adsorbents prepared in the laboratory exhibited comparatively more adsorption capacity than that of the parent material, fly ash. Further, used adsorbents can be disposed in the form of concrete blocks as leaching of toxic metals is almost nil both under mild acidic and basic conditions. As cost involved in developing adsorbents from fly ash is comparatively less than other commercial adsorbents, reactivation or regeneration of used adsorbents was not considered.

Porous Nanostructured Metals for Electrocatalysis

AbstractNanoporous metals have been used to enhance electrocatalysis. The origin of their capability is understood on the basis of enlarged surface area. On the other hand, the nanoconfined space of nanoporous metals can significantly affect the electrochemical efficiency. Moreover, molecular dynamics in nanoconfined spaces is capable of offering much more chances of interaction between a redox molecule and a metal surface. These unique properties come from simply nanoporous structure and suggest new opportunity to innovative electrocatalysts in the future. This review addresses recent advances in the field of nanoporous metals and discusses respective important electrocatalytic applications.

Tetralogy of Fallot and Aortic Root Dilation: A Long-Term Outlook

Dilation of the sinus of Valsalva (SoV) has been increasingly observed after repaired tetralogy of Fallot (TOF). We estimate the prevalence of SoV dilation in adults with repaired TOF and analyze possible factors related to aortic disease. Adults with TOF [n = 109, median age 33.2 years (range 18.1 to 69.5)] evaluated at Johns Hopkins Hospital from 2001 to 2009 were reviewed in an observational retrospective cohort study. Median follow-up was 27.3 (range 0.1-48.8) years. SoV dilation was defined as >95 % confidence interval adjusted for age and body surface area (z-score > 2). The prevalence of SoV dilation was 51 % compared with that of a normal population with a mean z-score of 2.03. Maximal aortic diameters were ≥ 4 cm in 39 % (42 of 109), ≥ 4.5 cm in 21 % (23 of 109), ≥ 5 cm in 8 % (9 of 109), and ≥ 5.5 cm in 2 % (2 of 109). There was no aortic dissection or death due contributable to aortic disease. Aortic valve replacement was performed in 1.8 % and aortic root or ascending aorta (AA) replacement surgery in 2.8 % of patients. By multivariate logistic regression analysis, aortic regurgitation (AR) [odds ratio (OR) = 3.09, p = 0.005], residual ventricular septal defect (VSD) (OR = 4.14, p < 0.02), and TOF with pulmonary atresia (TOF/PA) (OR = 6.75, p = 0.03) were associated with increased odds of dilated aortic root. SoV dilation after TOF repair is common and persists with aging. AR, residual VSD, and TOF/PA are associated with increased odds of dilation. AA evaluation beyond the SoV is important. Indexed values are imperative to avoid bias on the basis of age and body surface area.

Structural separations by ion mobility-MS for glycomics and glycoproteomics.

This chapter describes the utility of ion mobility-mass spectrometry (IM-MS) for the detection and characterization of glycoproteins and associated glycoconjugates. IM-MS provides separations in two dimensions; one on the basis of molecular surface area or structure, and the other on molecular mass which creates the ability to differentiate biomolecular classes and isobaric species. When applied to the characterization of glycoproteins, IM-MS separates peptides from the associated glycans in the same digest without purification, and can also be used to separate different isomeric glycans which is a significant challenge in current glycomic studies. The chapter details the methodologies to use IM-MS for the study of glycans and glycoproteins for an audience ranging from new and potential practitioners to those already utilizing the technique.

Phase II tailored S-1 regimen study of first-line chemotherapy in elderly patients with advanced and recurrent non-small cell lung cancer

We investigated the efficacy and toxicity of a novel oral 5-fluorouracil (5-FU) formulation (S-1), administered according to a tailored dose regimen. S-1 was administered orally for 28 days, followed by 14 days of no treatment, in 23 patients who received a tailored dose of S-1, adjusted on the basis of individual creatinine clearance and body surface area. In 8 of the patients, pharmacokinetic study was performed on the 6 points on 7th day after S-1 administration. Of the 23 patients enrolled in this study, 2 (8.7 %) had a partial response and 14 (60.9 %) had stable disease. The disease control rate was 69.6 % (16/23) (95 % confidence interval, 50.8-88.4 %). Grade 3/4 hematologic and non-hematologic toxicities were minor. In the pharmacokinetic study group, the maximum plasma concentration (C (max)) and the area under the plasma concentration curve of 5-FU at all 6 points after administration of the tailored S-1 dose regimen were similar to the values reported in a previous study describing cancer patients with normal renal function who received a standard dose of S-1 (80 mg/m(2)/day). Our results suggest that tailored S-1 monotherapy is safe and therapeutically useful as first-line treatment for elderly patients with advanced and recurrent non-small cell lung cancer.

Tolerability of adjuvant chemotherapy with S-1 after curative resection in patients with stage II/III gastric cancer

The results of the Japan Clinical Oncology Group trial demonstrated that adjuvant chemotherapy with S-1 for stage II/III gastric cancer is effective and suggested that this therapy should be adopted as the standard treatment following curative D2 gastric dissection. We reviewed treatment outcomes in 58 consecutive patients who received adjuvant therapy with S-1 for stage II/III gastric cancer following curative D2 dissection; the standard dosage used was determined on the basis of the patient body surface area. Twenty-four patients (41.3%) discontinued treatment before 12 months. Patients who completed 12 months of adjuvant therapy with S-1 were younger and more frequently treated by senior doctors (>15 years of experience) than those who did not. However, no differences existed in pathological features and surgical procedures between groups. Overall survival and relapse-free survival were better in patients who completed 12 months of adjuvant therapy with S-1. Fatigue and nausea were associated with discontinuation of S-1 treatment. In conclusion, immediately after surgery, fatigue and gastrointestinal symptoms of ≤ grade 2 may have a major impact on treatment compliance. Prior to the commencement of S-1 administration, both patients and doctors should be made completely aware of the toxicity, compliance and efficacy issues associated with this adjuvant therapy.

Biophysical Limits of Protein–Ligand Binding

In classic work, Kuntz et al. (Proc. Nat. Acad. Sci. USA 1999, 96, 9997-10002) introduced the concept of ligand efficiency. Though that study focused primarily on drug-like molecules, it also showed that metal binding led to the greatest ligand efficiencies. Here, the physical limits of binding are examined across the wide variety of small molecules in the Binding MOAD database. The complexes with the greatest ligand efficiencies share the trait of being small, charged ligands bound in highly charged, well buried binding sites. The limit of ligand efficiency is -1.75 kcal/mol·atom for the protein-ligand complexes within Binding MOAD, and 95% of the set have efficiencies below a "soft limit" of -0.83 kcal/mol·atom. On the basis of buried molecular surface area, the hard limit of ligand efficiency is -117 cal/mol·Å(2), which is in surprising agreement with the limit of macromolecule-protein binding. Close examination of the most efficient systems reveals their incredibly high efficiency is dictated by tight contacts between the charged groups of the ligand and the pocket. In fact, a misfit of 0.24 Å in the average contacts inherently decreases the maximum possible efficiency by at least 0.1 kcal/mol·atom.

Proton-promoted dissolution of α-FeOOH nanorods and microrods: Size dependence, anion effects (carbonate and phosphate), aggregation and surface adsorption

Iron-containing oxide nanoparticles are of great interest from a number of technological perspectives and they are also present in the natural environment. Although recent evidence suggests that particle size plays an important role in the dissolution of metal oxides, a detailed fundamental understanding of the influence of particle size is just beginning to emerge. In the current study, we investigate whether nanoscale size-effects are observed for the dissolution of iron oxyhydroxide under different conditions. The dissolution of two particle sizes of goethite, α-FeOOH in the nanoscale and microscale size regimes (herein referred to as nanorods and microrods), in aqueous suspensions at pH 2 is investigated. It is shown here that in the presence of nitrate, nanorods shows greater dissolution on both a per mass and per surface area basis relative to microrods, in agreement with earlier studies. In the presence of carbonate and phosphate, however, dissolution of α-FeOOH nanorods at pH 2 is significantly inhibited, despite the fact that these anions result in a three- to fivefold enhancement of the dissolution of microrods relative to the nitrate anion. Light scattering techniques and electron microscopy show that nanorod suspensions are less stable compared to microrod suspensions resulting in nanorod aggregation under conditions where microrods stay more dispersed. Furthermore, spectroscopic studies using ATR–FTIR spectroscopy show distinct differences in phosphate and carbonate adsorption on nanorods compared to microrods. These results demonstrate that aggregation and the details of surface adsorption are important in the dissolution behavior of nanoscale materials.

Adsorption of Four Representative Biological Compounds onto Graphite Nanofibers

The present study investigates the adsorption of four compounds important in carbon adsorption hemoperfusion. Graphite nanofibers (GNFs) having different carbon plane orientations have structural features that make them potentially attractive in this application compared to activated carbon. Generally, adsorption capacity increased in the order of ribbon > herringbone > platelet fiber types. All fibers were poor adsorbents for creatinine. Herringbone and platelet fibers had sorption capacities less than 25% of activated carbon for all adsorbates on a mass basis. Except for vitamin B12, behavior of ribbon fibers was similar; vitamin B12 adsorption was nearly 50% greater than activated carbon on a mass basis. In contrast, on the basis of surface area, all of the fibers were comparable to or outperformed activated carbon for the adsorption of all adsorbates. This suggests that in addition to BET surface area, interactions between adsorbate and exposed basal planes in carbon are important in determining adsor...