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1.
J Org Chem ; 88(15): 10881-10904, 2023 Aug 04.
Article in English | MEDLINE | ID: mdl-37441763

ABSTRACT

The synthesis of di- and trisubstituted vinyl fluorides with high isomeric purity remains a challenge for organic synthesis. While many methods exist to access these compounds, the separation of the desired isomer from the minor isomer and/or starting materials often is difficult. Herein, we report a practical method to access di- and trisubstituted vinyl fluorides via a selective Horner-Wadsworth-Emmons olefination/hydrolysis, which provides crystalline 2-fluoroacrylic acids in high (>98%) E-isomeric purity. A subsequent silver-catalyzed stereoretentive decarboxylation provides the title substances with high isomeric purity and without the need for tedious chromatography to remove the minor isomer. The process was amenable to a variety of aldehydes and ketones and provided a diverse array of di- and trisubstituted vinyl fluorides. The sequence was applied to the synthesis of antibacterial and anti-inflammatory compounds.

2.
Am Surg ; 89(6): 2777-2779, 2023 Jun.
Article in English | MEDLINE | ID: mdl-34734534

ABSTRACT

Giant paraesophageal hernias contain greater than fifty percent of the stomach above the diaphragm. Over fifty percent of large bowel obstructions are due to colorectal adenocarcinoma. Here, we present a rare case of a 69-year-old female patient who developed a closed loop colonic obstruction caused by a colonic mass in the distal transverse colon within a giant paraesophageal hernia. We successfully performed emergent paraesophageal hernia reduction and mesh repair with extended right hemicolectomy and ileocolonic anastomosis. Emergent hernia repair via an abdominal approach can be used in this setting.


Subject(s)
Colon, Transverse , Hernia, Hiatal , Intestinal Obstruction , Laparoscopy , Female , Humans , Aged , Hernia, Hiatal/diagnosis , Hernia, Hiatal/diagnostic imaging , Colon, Transverse/diagnostic imaging , Colon, Transverse/surgery , Diaphragm , Stomach , Intestinal Obstruction/diagnostic imaging , Intestinal Obstruction/etiology , Intestinal Obstruction/surgery , Laparoscopy/adverse effects
3.
Environ Sci Technol ; 56(12): 7729-7740, 2022 06 21.
Article in English | MEDLINE | ID: mdl-35670821

ABSTRACT

Tracking Saharan-Sahelian dust across the globe is essential to elucidate its effects on Earth's climate, radiation budget, hydrologic cycle, nutrient cycling, and also human health when it seasonally enters populated/industrialized regions of Africa, Europe, and North America. However, the elemental composition of mineral dust arising locally from construction activities and aeolian soil resuspension overlaps with African dust. Therefore, we derived a novel "isotope-resolved chemical mass balance" (IRCMB) method by employing radiogenic strontium, neodymium, and hafnium isotopes to accurately differentiate and quantitatively apportion collinear proximal and synoptic-scale crustal and anthropogenic mineral dust sources. IRCMB was applied to two air masses that transported African dust to Barbados and Texas to track particulate matter (PM) spikes at both locations. During Saharan-Sahelian intrusions, the radiogenic content of urban PM2.5 increased with respect to 87Sr/86Sr and 176Hf/177Hf but decreased in terms of 143Nd/144Nd, demonstrating the ability of these isotopes to sensitively track African dust intrusions even in complex metropolitan atmospheres. The principal aerosol strontium, neodymium, and hafnium end members were concrete dust and soil, soil and motor vehicles, and motor vehicles and North African dust, respectively. IRCMB separated and quantified local soil and distal crustal dust even when PM2.5 concentrations were low, opening a promising source apportionment avenue for urbanized/industrialized atmospheres.


Subject(s)
Air Pollutants , Particulate Matter , Aerosols/analysis , Air Pollutants/analysis , Atmosphere , Dust/analysis , Environmental Monitoring/methods , Hafnium/analysis , Humans , Isotopes , Minerals , Neodymium/analysis , Particulate Matter/analysis , Soil , Strontium , Texas
4.
Talanta ; 241: 123236, 2022 May 01.
Article in English | MEDLINE | ID: mdl-35074680

ABSTRACT

We present novel chemical separation protocols for isotopic analysis of low mass aliquots (0.3 mg and 25 mg) of several reference materials and real-world samples of relevance to urban airborne particulate matter (PM) investigations. A high-yielding gravity flow column chromatography scheme was developed for facile and quantitative separation of Sr, Nd, and Hf prior to multi collector - inductively coupled plasma - mass spectrometry (MC-ICP-MS). Because we are interested in isolating and accurately quantitating individual anthropogenic and natural aerosol sources in complex industrial/metropolitan atmospheric environments, laboratory protocols were optimized using National Institute of Standards and Technology Standard Reference Material (SRM) 1648a (urban atmospheric PM), SRM 1633b (coal fly ash), and European Commission standards BCR-723 (vehicular road dust), and BCR-2 (basalt rock standard). Sr, Nd, and Hf procedural blanks from column chromatography were low (averaging only 37 pg, 17 pg, 11 pg, respectively) and recoveries were high (averaging 95%, 82%, and 92%, respectively). A volume-adjustment protocol was established using isotope reference solutions SRM 987 (SrCO3), JNdi (Nd2O3), and in-house Hf standards to dilute the dried samples prior to MC-ICP-MS based on projected uncertainties for low sample masses. 87Sr/86Sr, 143Nd/144Nd, and 176Hf/177Hf isotopic ratios in SRM 1648a, BCR-723, and SRM 1633b are reported for the first time that can serve as provisional reference values. The novel method was used to characterize isotopic ratios and elemental abundances in two anthropogenic urban aerosol sources, namely motor vehicles and petroleum refining using airborne fine PM collected in a vehicular tunnel and fluidized-bed catalytic cracking catalysts, respectively. Two other important mineral-rich urban PM sources, namely soil (i.e., resuspended crustal material) and concrete/cement dust (i.e., construction activity) were also characterized. These are the first isotopic measurements in these environmental compartments and were compared with literature data for long-range transported North African dust, which is a prominent summertime PM source in urban regions in southeastern United States. We demonstrate the capability of coupled Sr-Nd-Hf isotopes to uniquely trace different mineral dust sources with overlapping elemental composition (Sahara-Sahel region, local soil, and concrete/cement) and accurately isolate various urban PM sources demonstrating the superiority of isotopic markers over elemental tracers.


Subject(s)
Air Pollutants , Particulate Matter , Aerosols/analysis , Air Pollutants/analysis , Atmosphere , Dust/analysis , Environmental Monitoring/methods , Particulate Matter/analysis
5.
Article in English | MEDLINE | ID: mdl-34531632

ABSTRACT

Renal segmentation on contrast-enhanced computed tomography (CT) provides distinct spatial context and morphology. Current studies for renal segmentations are highly dependent on manual efforts, which are time-consuming and tedious. Hence, developing an automatic framework for the segmentation of renal cortex, medulla and pelvicalyceal system is an important quantitative assessment of renal morphometry. Recent innovations in deep methods have driven performance toward levels for which clinical translation is appealing. However, the segmentation of renal structures can be challenging due to the limited field-of-view (FOV) and variability among patients. In this paper, we propose a method to automatically label the renal cortex, the medulla and pelvicalyceal system. First, we retrieved 45 clinically-acquired deidentified arterial phase CT scans (45 patients, 90 kidneys) without diagnosis codes (ICD-9) involving kidney abnormalities. Second, an interpreter performed manual segmentation to pelvis, medulla and cortex slice-by-slice on all retrieved subjects under expert supervision. Finally, we proposed a patch-based deep neural networks to automatically segment renal structures. Compared to the automatic baseline algorithm (3D U-Net) and conventional hierarchical method (3D U-Net Hierarchy), our proposed method achieves improvement of 0.7968 to 0.6749 (3D U-Net), 0.7482 (3D U-Net Hierarchy) in terms of mean Dice scores across three classes (p-value < 0.001, paired t-tests between our method and 3D U-Net Hierarchy). In summary, the proposed algorithm provides a precise and efficient method for labeling renal structures.

6.
DNA Repair (Amst) ; 108: 103213, 2021 12.
Article in English | MEDLINE | ID: mdl-34464900

ABSTRACT

Fapy•dG and 8-OxodGuo are formed in DNA from a common N7-dG radical intermediate by reaction with hydroxyl radical. Although cellular levels of Fapy•dG are often greater, its effects on replication are less well understood than those of 8-OxodGuo. In this study plasmid DNA containing Fapy•dG in three mutational hotspots of human cancers, codons 248, 249, and 273 of the p53 tumor suppressor gene, was replicated in HEK 293T cells. TLS efficiencies for the Fapy•dG containing plasmids varied from 72 to 89%, and were further reduced in polymerase-deficient cells. The mutation frequency (MF) of Fapy•dG ranged from 7.3 to 11.6%, with G→T and G→A as major mutations in codons 248 and 249 compared to primarily G→T in codon 273. Increased MF in hPol ι-, hPol κ-, and hPol ζ-deficient cells suggested that these polymerases more frequently insert the correct nucleotide dC opposite Fapy•dG, whereas decreased G→A in codons 248 and 249 and reduction of all mutations in codon 273 in hPol λ-deficient cells indicated hPol λ's involvement in Fapy•dG mutagenesis. In vitro kinetic analysis using isolated translesion synthesis polymerases and hPol λ incompletely corroborated the mutagenesis experiments, indicating codependence on other proteins in the cellular milieu. In conclusion, Fapy•dG mutagenesis is dependent on the DNA sequence context, but its bypass by the TLS polymerases is largely error-free.


Subject(s)
DNA Adducts , Formamides , Furans , Genes, p53 , Pyrimidines , DNA Damage , DNA Replication , Humans , Kinetics , Mutation , Tumor Suppressor Protein p53/genetics
7.
J Organomet Chem ; 9362021 Mar 15.
Article in English | MEDLINE | ID: mdl-33953436

ABSTRACT

Tricarbonylrhenium(I)(α-diimine) complexes are of importance because of their strong cytotoxic and fluorescence properties. Syntheses of such complexes were achieved through a two-step process. First, the pentylcarbonato complexes, fac-(CO)3(α-diimine)ReOC(O)OC5H11 were synthesized through a microwave-assisted reaction of Re2(CO)10, α-diimine, 1-pentanol and CO2 in a few hours. Second, the pentylcarbonato complexes are treated with carboxylic, sulfonic and halo acids to obtain the corresponding carboxylato, sulfonato and halido complexes. This is the first example of conversion of Re2(CO)10 into a rhenium carbonyl complex through microwave-assisted reaction.

8.
Med Phys ; 48(3): 1276-1285, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33410167

ABSTRACT

PURPOSE: Dynamic contrast-enhanced computed tomography (CT) is widely used to provide dynamic tissue contrast for diagnostic investigation and vascular identification. However, the phase information of contrast injection is typically recorded manually by technicians, which introduces missing or mislabeling. Hence, imaging-based contrast phase identification is appealing, but challenging, due to large variations among different contrast protocols, vascular dynamics, and metabolism, especially for clinically acquired CT scans. The purpose of this study is to perform imaging-based phase identification for dynamic abdominal CT using a proposed adversarial learning framework across five representative contrast phases. METHODS: A generative adversarial network (GAN) is proposed as a disentangled representation learning model. To explicitly model different contrast phases, a low dimensional common representation and a class specific code are fused in the hidden layer. Then, the low dimensional features are reconstructed following a discriminator and classifier. 36 350 slices of CT scans from 400 subjects are used to evaluate the proposed method with fivefold cross-validation with splits on subjects. Then, 2216 slices images from 20 independent subjects are employed as independent testing data, which are evaluated using multiclass normalized confusion matrix. RESULTS: The proposed network significantly improved correspondence (0.93) over VGG, ResNet50, StarGAN, and 3DSE with accuracy scores 0.59, 0.62, 0.72, and 0.90, respectively (P < 0.001 Stuart-Maxwell test for normalized multiclass confusion matrix). CONCLUSION: We show that adversarial learning for discriminator can be benefit for capturing contrast information among phases. The proposed discriminator from the disentangled network achieves promising results.


Subject(s)
Image Processing, Computer-Assisted , Tomography, X-Ray Computed , Abdomen , Humans , Tomography, Spiral Computed
9.
DNA Repair (Amst) ; 95: 102935, 2020 11.
Article in English | MEDLINE | ID: mdl-32721818

ABSTRACT

6-Nitrochrysene (6-NC) is a potent mutagen in bacteria and carcinogenic in animals. It is the most potent carcinogen ever tested in newborn mouse assay. DNA lesions resulting from 6-NC modification are likely to induce mutations if they are not removed by cellular defense pathways prior to DNA replication. Earlier studies showed that 6-NC-derived C8-2'-deoxyadenosine adduct, N-(dA-8-yl)-6-AC, is very slowly repaired in human cells. In this study, we have investigated replication of N-(dA-8-yl)-6-AC in human embryonic kidney (HEK 293T) cells and the roles of translesion synthesis (TLS) DNA polymerases in bypassing it. Replication of a plasmid containing a single site-specific N-(dA-8-yl)-6-AC adduct in HEK 293 T cells showed that human DNA polymerase (hPol) η and hPol κ played important roles in bypassing the adduct, since TLS efficiency was reduced to 26 % in the absence of these two polymerases compared to 83 % in polymerase-competent HEK 293T cells. The progeny from HEK 293T cells provided 12.7 % mutants predominantly containing A→T transversions. Mutation frequency (MF) was increased to 17.8 % in hPol η-deficient cells, whereas it was decreased to 3.3 % and 3.9 % when the adduct containing plasmid was replicated in hPol κ- and hPol ζ-deficient cells, respectively. The greatest reduction in MF by more than 90 % (to MF 1.2 %) was observed in hPol ζ-knockout cells in which hPol κ was knocked down. Taken together, these results suggest that hPol κ and hPol ζ are involved in the error-prone TLS of N-(dA-8-yl)-6-AC, while hPol η performs error-free bypass.


Subject(s)
Chrysenes/chemistry , DNA Adducts/metabolism , DNA Repair , DNA-Binding Proteins/metabolism , DNA-Directed DNA Polymerase/metabolism , Deoxyadenosines/chemistry , DNA Adducts/chemistry , DNA Replication , HEK293 Cells , Humans
10.
Chem Res Toxicol ; 33(2): 604-613, 2020 02 17.
Article in English | MEDLINE | ID: mdl-31903755

ABSTRACT

6-Nitrochrysene (6-NC), the most potent carcinogen evaluated by the newborn mouse assay, is metabolically activated by nitroreduction and a combination of ring oxidation and nitroreduction pathways. The nitroreduction pathway yields three major DNA adducts: at the C8 and N2 positions of 2'-deoxyguanosine (dG), N-(dG-8-yl)-6-AC and 5-(dG-N2-yl)-6-AC, and at the C8 position of 2'-deoxyadenosine (dA), N-(dA-8-yl)-6-AC. A nucleotide excision repair assay demonstrated that N-(dA-8-yl)-6-AC is repaired much more slowly than many other bulky DNA adducts, including the other DNA adducts formed by 6-NC. But neither the total synthesis nor evaluation of other biological activities of this dA adduct has ever been reported. Herein, we report a convenient synthesis of the 6-NC-derived dA adduct by employing the Buchwald-Hartwig coupling strategy, which provided a high yield of the protected N-(dA-8-yl)-6-AC. The deprotected nucleoside showed syn conformational preference by NMR spectroscopy. Following DMT protection of the 5'-hydroxyl, N-(dA-8-yl)-6-AC was converted to its 3'-phosphoramidite, which was used to prepare oligonucleotides containing a single N-(dA-8-yl)-6-AC adduct. Circular dichroism spectra of the adducted duplex showed only a slight departure from the B-DNA helix profile of the control duplex. The 15-mer N-(dA-8-yl)-6-AC oligonucleotide was used to construct a single-stranded plasmid vector containing a single adduct, which was replicated in Escherichia coli. Viability of the adducted construct was ∼60% of the control, indicating slower translesion synthesis of the adduct, which increased to nearly 90% upon induction of the SOS functions. Without SOS, the mutation frequency (MF) of the adduct was 5.2%, including 2.9% targeted and 2.3% semi-targeted mutations. With SOS, the targeted MF increased 3-fold to 9.0%, whereas semi-targeted mutation increased only marginally to 3.2%. The major type of targeted mutation was A*→G in both uninduced and SOS-induced cells.


Subject(s)
DNA Adducts/genetics , Deoxyadenosines/genetics , Escherichia coli/genetics , Mutagenesis, Site-Directed , Oligodeoxyribonucleotides/genetics , DNA Adducts/chemistry , DNA Adducts/metabolism , Deoxyadenosines/chemistry , Deoxyadenosines/metabolism , Escherichia coli/metabolism , Molecular Structure , Oligodeoxyribonucleotides/chemistry , Oligodeoxyribonucleotides/metabolism
11.
J Cancer Sci Ther ; 10(2)2018.
Article in English | MEDLINE | ID: mdl-29707104

ABSTRACT

PURPOSE: Because of the scarcity of suitable brain cancer drugs, researchers are frantically trying to discover novel and highly potent drugs free of side effects and drug-resistance. Rhenium compounds are known to be nontoxic and exhibit no drug resistance. For that reason, we have developed a series of novel rhenium acetylsalicylato (RAC or ASP) complexes to test their cytotoxicity on brain cancer cells. Also we have attempted to explore the DNAbinding properties of these compounds because many drugs either directly or indirectly bind to DNA. METHODS: We have treated the RAC series compounds on human astrocytoma brain cancer cell lines and rat normal brain astrocyte cells and determined the efficacy of these complexes through in vitro cytotoxicity assay. We carried out the DNA-binding study through UV titrations of a RAC compound with DNA. Also we attempted to determine the planarity of the polypyridyl ligands of the RAC series compounds using DFT calculations. RESULTS: RAC6 is more potent than any other RAC series compounds on HTB-12 human astrocytoma cancer cells as well as on Glioblastoma Multiforme D54 cell lines. In fact, The IC-50 value of RAC6 on HTB-12 cancer cells is approximately 2 µM. As expected, the RAC series compounds were not active on normal cells. The DFT calculations on the RAC series compounds were done and suggest that the polypyridyl ligands in the complexes are planar. The UV-titrations of RAC9 with DNA were carried out. It suggests that RAC9 and possibly all RAC series compounds bind to minor grooves of the DNA. CONCLUSION: Because of the very low activity of RAC6 on normal cells and low lC50 value of on astrocytoma (HTB-12) cell lines, it is possible that RAC6 and its derivatives may potentially find application in the treatment of brain cancers. The DFT calculations and UV titrations suggest that RAC series compounds either bind to DNA intercalatively or minor grooves of the DNA or both. However, it is highly premature to make any definite statement in the absence of other techniques.

12.
Mol Cell Biochem ; 441(1-2): 151-163, 2018 Apr.
Article in English | MEDLINE | ID: mdl-28913709

ABSTRACT

Cisplatin and other metal-based drugs often display side effects and tumor resistance after prolonged use. Because rhenium-based anticancer complexes are often less toxic, a novel series of organorhenium complexes were synthesized of the types: XRe(CO)3Z (X = α-diimines and Z = p-toluenesulfonate, 1-naphthalenesulfonate, 2-naphthalenesulfonate, picolinate, nicotinate, aspirinate, naproxenate, flufenamate, ibuprofenate, mefenamate, tolfenamate, N-acetyl-tryptophanate), and their biological properties were examined. Specifically, in hormone-dependent MCF-7 and hormone-independent triple-negative MDA-MB-231 breast cancer cells, the p-toluenesulfonato, 1-naphthalenesulfonato, 2-naphthalenesulfonato, picolinato, nicotinato, acetylsalicylato, flufenamato, ibuprofenato, mefenamato, and N-acetyl-tryptophanato complexes were found to be far more potent than conventional drug cisplatin. DNA-binding studies were performed in each case via UV-Vis titrations, cyclic voltammetry, gel electrophoresis, and viscosity, which suggest DNA partial intercalation interaction, and the structure-activity relationship studies suggest that the anticancer activities increase with the increasing lipophilicities of the compounds, roughly consistent with their DNA-binding activities.


Subject(s)
Antineoplastic Agents , Coordination Complexes , Organometallic Compounds , Rhenium , Triple Negative Breast Neoplasms/drug therapy , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Coordination Complexes/chemistry , Coordination Complexes/pharmacology , Female , Humans , MCF-7 Cells , Organometallic Compounds/chemistry , Organometallic Compounds/pharmacology , Rhenium/chemistry , Rhenium/pharmacology , Triple Negative Breast Neoplasms/metabolism , Triple Negative Breast Neoplasms/pathology
13.
Sci Rep ; 7(1): 12238, 2017 09 25.
Article in English | MEDLINE | ID: mdl-28947829

ABSTRACT

Multiple, independent time markers are essential to correlate sediment and ice cores from the terrestrial, marine and glacial realms. These records constrain global paleoclimate reconstructions and inform future climate change scenarios. In the Northern Hemisphere, sub-visible layers of volcanic ash (cryptotephra) are valuable time markers due to their widespread dispersal and unique geochemical fingerprints. However, cryptotephra are not as widely identified in the Southern Hemisphere, leaving a gap in the climate record, particularly during the Last Glacial Maximum (LGM). Here we report the first identification of New Zealand volcanic ash in Antarctic ice. The Oruanui supereruption from Taupo volcano (25,580 ± 258 cal. a BP) provides a key time marker for the LGM in the New Zealand sector of the SW Pacific. This finding provides a high-precision chronological link to mid-latitude terrestrial and marine sites, and sheds light on the long-distance transport of tephra in the Southern Hemisphere. As occurred after identification of the Alaskan White River Ash in northern Europe, recognition of ash from the Oruanui eruption in Antarctica dramatically increases the reach and value of tephrochronology, providing links among climate records in widely different geographic areas and depositional environments.

15.
Nature ; 534(7606): 249-53, 2016 06 09.
Article in English | MEDLINE | ID: mdl-27279222

ABSTRACT

Recent excavations at the early Middle Pleistocene site of Mata Menge in the So'a Basin of central Flores, Indonesia, have yielded hominin fossils attributed to a population ancestral to Late Pleistocene Homo floresiensis. Here we describe the age and context of the Mata Menge hominin specimens and associated archaeological findings. The fluvial sandstone layer from which the in situ fossils were excavated in 2014 was deposited in a small valley stream around 700 thousand years ago, as indicated by (40)Ar/(39)Ar and fission track dates on stratigraphically bracketing volcanic ash and pyroclastic density current deposits, in combination with coupled uranium-series and electron spin resonance dating of fossil teeth. Palaeoenvironmental data indicate a relatively dry climate in the So'a Basin during the early Middle Pleistocene, while various lines of evidence suggest the hominins inhabited a savannah-like open grassland habitat with a wetland component. The hominin fossils occur alongside the remains of an insular fauna and a simple stone technology that is markedly similar to that associated with Late Pleistocene H. floresiensis.


Subject(s)
Archaeology , Environment , Fossils , Hominidae , Radiometric Dating , Animals , Argon , Climate , Electron Spin Resonance Spectroscopy , Grassland , History, Ancient , Indonesia , Radioisotopes , Tool Use Behavior , Tooth/chemistry , Volcanic Eruptions/history , Wetlands
16.
Nature ; 532(7599): 366-9, 2016 Apr 21.
Article in English | MEDLINE | ID: mdl-27027286

ABSTRACT

Homo floresiensis, a primitive hominin species discovered in Late Pleistocene sediments at Liang Bua (Flores, Indonesia), has generated wide interest and scientific debate. A major reason this taxon is controversial is because the H. floresiensis-bearing deposits, which include associated stone artefacts and remains of other extinct endemic fauna, were dated to between about 95 and 12 thousand calendar years (kyr) ago. These ages suggested that H. floresiensis survived until long after modern humans reached Australia by ~50 kyr ago. Here we report new stratigraphic and chronological evidence from Liang Bua that does not support the ages inferred previously for the H. floresiensis holotype (LB1), ~18 thousand calibrated radiocarbon years before present (kyr cal. BP), or the time of last appearance of this species (about 17 or 13-11 kyr cal. BP). Instead, the skeletal remains of H. floresiensis and the deposits containing them are dated to between about 100 and 60 kyr ago, whereas stone artefacts attributable to this species range from about 190 to 50 kyr in age. Whether H. floresiensis survived after 50 kyr ago--potentially encountering modern humans on Flores or other hominins dispersing through southeast Asia, such as Denisovans--is an open question.


Subject(s)
Archaeology , Fossils , Hominidae , Radiometric Dating , Aluminum Silicates , Animals , Australia , Calibration , Caves , Geologic Sediments/analysis , Glass , Humans , Indonesia , Potassium Compounds , Quartz , Time Factors , Uncertainty
17.
Zookeys ; (301): 1-12, 2013.
Article in English | MEDLINE | ID: mdl-23794891

ABSTRACT

The nymphs of Antillotolania Ramos and Deiroderes Ramos are described for the first time, along with the first host record for the genus Antillotolania, represented by Antillotolania myricae, sp. n. Nymphal features of both genera, such as a ventrally fused, cylindrical tergum IX (anal tube), the presence of abdominal lamellae, and heads with foliaceous ventrolateral lobes confirm their placement in Membracidae and are consistent with phylogenetic analyses placing them in Stegaspidinae but in conflict with a cladistic analysis showing a closer relationship to Nicomiinae. Head processes and emarginate forewing pads in the last instars of both genera support an earlier estimate, based on nuclear genes, that the two genera form a monophyletic group in Stegaspidinae. Distinguishing features of the four species of Antillotolania are tabulated.

18.
Bioorg Med Chem Lett ; 21(10): 2823-5, 2011 May 15.
Article in English | MEDLINE | ID: mdl-21493063

ABSTRACT

Continuing our interest in designing compounds preferentially potent and selective for MMP-13, we report on a series of hydroxamic acids with a flexible amide P1' substituents. We identify an amide which spares both MMP-1 and -14, and shows >500 fold selectivity for MMP-13 versus MMP-2 and -8.


Subject(s)
Amides/chemical synthesis , Hydroxamic Acids/chemical synthesis , Matrix Metalloproteinase Inhibitors , Protease Inhibitors/chemical synthesis , Amides/chemistry , Humans , Hydroxamic Acids/chemistry , Inhibitory Concentration 50 , Molecular Structure , Protease Inhibitors/chemistry , Structure-Activity Relationship , Substrate Specificity
19.
Oecologia ; 165(1): 111-22, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20730545

ABSTRACT

Phenotypic plasticity may be critical for nutrient-limited organisms that allocate ingested nutrients to the competing demands of reproduction and survivorship. Leafhoppers that feed on xylem fluid allow assessment of plasticity in response to the constant selective pressure of nutritional inadequacy. We examined feeding behavior (host selection and consumption rates) and nutrient allocation (fecundity, change in body mass and composition) of the xylem fluid-feeding leafhopper Homalodisca vitripennis (Hemiptera:Cicadellidae) on ten genotypes of related Prunus germplasm when adults first seasonally appear, and later during population peaks, to examine the effects of genotypes and season on plasticity of life history and behavioral traits. Behavior and resource allocation to life history traits were both mediated by xylem nutrients, although nutrients impacting behavior differed from those mediating life history. Host selection and consumption varied with genotype between June and July, yet behavior consistently reflected concentrations of dietary glutamine. Resource allocations also increased linearly with nutrient concentrations, but were best correlated to ingested essential amino acids rather than glutamine. Body mass and composition were highly correlated to dietary essential amino acids in June; 6 weeks later, fecundity was instead proportional to essential amino acids. The discrepancy in nutrients which impact behavior versus those mediating life history may explain the weak preference-performance linkage documented for many insects. The demarcation in allocating resources to biomass in June to fecundity in July suggests increased allocation to reproduction during periods of nutrient stress as predicted by the theory of optimal resource allocation; other contributing biotic and abiotic factors are also discussed.


Subject(s)
Behavior, Animal , Hemiptera/physiology , Animals , Body Composition , Body Size , Feeding Behavior , Phenotype , Prunus , Reproduction , Stress, Physiological , Xylem/chemistry
20.
World J Urol ; 29(1): 91-5, 2011 Feb.
Article in English | MEDLINE | ID: mdl-20204377

ABSTRACT

PURPOSE: Data regarding the treatment of ureteropelvic junction obstruction (UPJO) in horseshoe kidneys are limited. We performed a retrospective analysis of our experience with minimally invasive treatment of UPJO in patients with this anomaly. METHODS: Between March of 1996 and March 2008, 9 patients with horseshoe kidneys were treated for UPJO at our institution. Of these patients, 6 were managed with retrograde endopyelotomy, 2 with laparoscopic pyeloplasty, and one by robotic pyeloplasty. Outcomes of these procedures were retrospectively reviewed. RESULTS: A total of nine patients were available for analysis. Four of six patients who underwent endopyelotomy had available follow-up, with a mean of 56 months. The success rate for these patients was 75%. Two of three patients (67%) in the laparoscopic/robotic cohort were successfully treated with a mean follow-up of 21 months. CONCLUSIONS: UPJO in horseshoe kidneys can pose a therapeutic dilemma. The minimally invasive treatment of these patients is feasible with good success rates for both endopyelotomy and laparoscopic/robotic pyeloplasty.


Subject(s)
Kidney/abnormalities , Minimally Invasive Surgical Procedures/methods , Ureteral Obstruction/surgery , Urologic Surgical Procedures/methods , Adult , Aged , Female , Humans , Kidney/surgery , Male , Middle Aged , Minimally Invasive Surgical Procedures/adverse effects , Retrospective Studies , Treatment Outcome , Ureter/abnormalities , Ureter/surgery , Urologic Surgical Procedures/adverse effects
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