Spectral Analysis Methods for Improved Resolution and Sensitivity: Enhancing SPR and LSPR Optical Fiber Sensing.

Biochemical-chemical sensing with plasmonic sensors is widely performed by tracking the responses of surface plasmonic resonance peaks to changes in the medium. Interestingly, consistent sensitivity and resolution improvements have been demonstrated for gold nanoparticles by analyzing other spectral features, such as spectral inflection points or peak curvatures. Nevertheless, such studies were only conducted on planar platforms and were restricted to gold nanoparticles. In this work, such methodologies are explored and expanded to plasmonic optical fibers. Thus, we study-experimentally and theoretically-the optical responses of optical fiber-doped gold or silver nanospheres and optical fibers coated with continuous gold or silver thin films. Both experimental and numerical results are analyzed with differentiation methods, using total variation regularization to effectively minimize noise amplification propagation. Consistent resolution improvements of up to 2.2× for both types of plasmonic fibers are found, demonstrating that deploying such analysis with any plasmonic optical fiber sensors can lead to sensing resolution improvements.

Great Abundance of Satellite DNA in Proceratophrys (Anura, Odontophrynidae) Revealed by Genome Sequencing.

Most eukaryotic genomes contain substantial portions of repetitive DNA sequences. These are located primarily in highly compacted heterochromatin and, in many cases, are one of the most abundant components of the sex chromosomes. In this sense, the anuran Proceratophrys boiei represents an interesting model for analyses on repetitive sequences by means of cytogenetic techniques, since it has a karyotype with large blocks of heterochromatin and a ZZ/ZW sex chromosome system. The present study describes, for the first time, families of satellite DNA (satDNA) in the frog P. boiei. Its genome size was estimated at 1.6 Gb, of which 41% correspond to repetitive sequences, including satDNAs, rDNAs, transposable elements, and other elements characterized as non-repetitive. The satDNAs were mapped by FISH in the centromeric and pericentromeric regions of all chromosomes, suggesting a possible involvement of these sequences in centromere function. SatDNAs are also present in the W sex chromosome, occupying the entire heterochromatic area, indicating a probable contribution of this class of repetitive DNA to the differentiation of the sex chromosomes in this species. This study is a valuable contribution to the existing knowledge on repetitive sequences in amphibians. We show the presence of repetitive DNAs, especially satDNAs, in the genome of P. boiei that might be of relevance in genome organization and regulation, setting the stage for a deeper functional genome analysis of Proceratophrys.

Effects of dexmedetomidine combined with ropivacaine on sciatic and femoral nerve blockade in dogs.

OBJECTIVE: To evaluate motor and sensory blockade of combining dexmedetomidine with ropivacaine, administered perineurally or systemically, for femoral and sciatic nerve blocks in conscious dogs. STUDY DESIGN: Randomized, controlled, experimental study. ANIMALS: Seven healthy Beagle dogs, aged 3.3 ± 0.1 years and weighing 11.0 ± 2.4 kg. METHODS: Dogs were anesthetized with isoflurane on three separate occasions for unilateral femoral and sciatic nerve blocks and were administered the following treatments in random order: perineural ropivacaine 0.75% (0.1 mL kg-1) on each nerve and intramuscular (IM) saline (0.2 mL kg-1) (Gcon); perineural dexmedetomidine (1 µg mL-1) and ropivacaine 0.75% (0.1 mL kg-1) on each nerve and IM saline (0.2 mL kg-1) (GDPN); and perineural ropivacaine 0.75% (0.1 mL kg-1) on each nerve and IM dexmedetomidine (1 µg mL-1, 0.2 mL kg-1) (Gdim). Nerve blocks were guided by ultrasound and electrical stimulation and dogs were allowed to recover from general anesthesia. Sensory blockade was evaluated by response to clamp pressure on the skin innervated by the saphenous/ femoral, common fibular and tibial nerves. Motor blockade was evaluated by observing the ability to walk and proprioception. Sensory and motor blockade were evaluated until their full recovery. RESULTS: No significant differences in onset time to motor and sensory blockade were observed among treatments. Duration of motor blockade was not significantly different among treatments; however, duration of tibial sensory blockade was longer in the Gdpn than in the GDIM treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Although a longer duration of sensory blockade was observed with perineural dexmedetomidine, a significant increase compared with the control group was not established. Other concentrations should be investigated to verify if dexmedetomidine is a useful adjuvant to local anesthetics in peripheral nerve blocks in dogs.

Continuous infusion of propofol in calves: bispectral index and hemodynamic effects.

OBJECTIVE: To assess the bispectral index (BIS) and the hemodynamic effects of propofol administered by continuous infusion at different rates in calves. STUDY DESIGN: Experimental crossover study. ANIMALS: Eight intact male Dutch calves, aged 6-12 months and weighing 84-124 kg. METHODS: The calves were anesthetized with propofol (5 mg kg(-1) ) intravenously (IV), and after endotracheal intubation, positioned in right lateral recumbency and allowed to breathe ambient air. Anesthesia was maintained by continuous infusion of propofol, administered IV with an infusion pump at 0.6 mg kg(-1)  minute(-1) (treatment G6) or 0.8 mg kg(-1)  minute(-1) IV (treatment G8), for 60 minutes. The eight animals were anesthetized twice, 1 week apart. The following hemodynamic variables and BIS were assessed before the induction of anesthesia (baseline) and 15, 30, 45, and 60 minutes after beginning the infusion of propofol: heart rate, systolic, diastolic and mean arterial pressures, cardiac output, mean pulmonary artery pressure, cardiac index, stroke index, pulmonary vascular resistance index, and systemic vascular resistance index, BIS, electromyography, and signal quality index. RESULTS: The continuous infusions of propofol at different rates did not alter BIS variables during the infusion time between dose rates, and no clinically significant hemodynamic changes were observed. CONCLUSIONS AND CLINICAL RELEVANCE: A continuous infusion of propofol at 0.6 or 0.8 mg kg(-1)  minute(-1) caused minimal hemodynamic changes without clinical relevance in calves. BIS could not be reliably used to discriminate the anesthetic depth during the two propofol infusion rates.

Tumescent local anesthesia with ropivacaine in different concentrations in bitches undergoing mastectomy: plasma concentration and post-operative analgesia.

OBJECTIVE: To compare two concentrations of ropivacaine administered for tumescent local anesthesia (TLA) in dogs undergoing mastectomy. STUDY DESIGN: Prospective randomized clinical study. ANIMALS: Seventeen bitches of various breeds, aged 12 ± 2 years and weighing 10 ± 6.5 kg requiring total unilateral or bilateral mastectomy. METHODS: Dogs were premedicated with acepromazine (0.04 mg kg(-1) ) and morphine (0.4 mg kg(-1) ) intramuscularly. Anesthesia was induced with propofol (2.5 mg kg(-1) ) and midazolam (0.2 mg kg(-1) ) intravenously, followed by intubation and maintenance with isoflurane and TLA. Dogs were randomly allocated to receive TLA either with 0.1% ropivacaine (group G1) or with 0.05% ropivacaine (group G05). TLA was performed by insertion of a multihole needle under the skin and infusion of ropivacaine and lactated Ringer's solution at a fixed volume of 15 mL kg(-1) . Ropivacaine concentrations in arterial blood were measured by high-performance liquid chromatography. Post-operative pain was assessed using two scales (University of Melbourne pain scale and a modified composite measure pain scale) and von Frey filaments, 4 hours after TLA and at 1 hour intervals until sensitivity was regained. A score above 30% of the maximum possible score was considered a positive indicator of pain. RESULTS: Peak plasma concentrations of ropivacaine were measured 240 minutes after TLA in G1. Low concentrations were measured in G05 for 60 minutes, with subsequent increase. Analgesic rescue and return of sensitivity occurred at 7 ± 2.3 and 7 ± 1.9 hours (mean ± SD) after TLA for G1 and G05, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Tumescent local anesthesia with ropivacaine provided satisfactory post-operative analgesia that lasted for several hours, with no difference in duration between the concentrations. No serious side effects were attributed to TLA. Results indicated that 0.05% ropivacaine provided adequate analgesia for mastectomy, however, more studies are required to support this conclusion.

Plasmonic nanoparticle sensors: current progress, challenges, and future prospects.

Plasmonic nanoparticles (NPs) have played a significant role in the evolution of modern nanoscience and nanotechnology in terms of colloidal synthesis, general understanding of nanocrystal growth mechanisms, and their impact in a wide range of applications. They exhibit strong visible colors due to localized surface plasmon resonance (LSPR) that depends on their size, shape, composition, and the surrounding dielectric environment. Under resonant excitation, the LSPR of plasmonic NPs leads to a strong field enhancement near their surfaces and thus enhances various light-matter interactions. These unique optical properties of plasmonic NPs have been used to design chemical and biological sensors. Over the last few decades, colloidal plasmonic NPs have been greatly exploited in sensing applications through LSPR shifts (colorimetry), surface-enhanced Raman scattering, surface-enhanced fluorescence, and chiroptical activity. Although colloidal plasmonic NPs have emerged at the forefront of nanobiosensors, there are still several important challenges to be addressed for the realization of plasmonic NP-based sensor kits for routine use in daily life. In this comprehensive review, researchers of different disciplines (colloidal and analytical chemistry, biology, physics, and medicine) have joined together to summarize the past, present, and future of plasmonic NP-based sensors in terms of different sensing platforms, understanding of the sensing mechanisms, different chemical and biological analytes, and the expected future technologies. This review is expected to guide the researchers currently working in this field and inspire future generations of scientists to join this compelling research field and its branches.

Cardiopulmonary and analgesic effects of caudal epidurally administered ropivacaine in cattle.

OBJECTIVE: To assess cardiopulmonary and analgesic effects after administration of ropivacaine into the caudal epidural space of cattle. STUDY DESIGN: Prospective, single-dose trial. ANIMALS: Eight healthy mixed breed cows aged 8 ± 5 years and weighing 507 ± 112 kg. METHODS: Caudal epidural anesthesia was produced in cows with 0.75% ropivacaine (0.11 mg kg(-1)). Onset time, duration and cranial spread of analgesia were recorded. Heart rate (HR), respiratory rate (f(R)), rectal temperature (RT), and mean arterial blood pressure (MAP) were measured prior to epidural administration (T(0) ) and at 15, 30, 60, 120, 180 and 240 minutes after epidural administration (T(15), T(30), T(60) , T(120) , T(180) and T(240) ). Arterial blood acid-base balance (pH, standard bicarbonate and base excess), gas tension (PaO(2), PaCO(2), SaO(2)) and electrolytes (Na(+), K(+), iCa(2+),Cl(-)) were recorded at T(0), T(30), T(60), T(120), T(180) and T(240). Ataxia was evaluated at T(0), T(30), T(60), T(120), T(180) and T(240) and at 1 hour intervals thereafter until analgesia was no longer present in each animal. RESULTS: Epidurally administered ropivacaine induced variable analgesia extending bilaterally from the coccyx to S3. Time to onset of analgesia and mean duration in the perineal area were 15 ± 4 and 359 ± 90 minutes, respectively. Respiratory rate and RT increased from T(120) to T(240) when compared to the value at T(0) . Ionized calcium and chloride concentrations increased at T(180) and T(240) when compared to T(0). The other variables were not significantly different from baseline values (p > 0.05). Four animals were mildly ataxic. CONCLUSION AND CLINICAL RELEVANCE: Ropivacaine (0.75%, 0.11 mg kg(-1)) can be administered by caudal epidural injection to produce prolonged bilateral perineal analgesia with minimal ataxia and cardiopulmonary changes in standing cattle.

Artificial intelligence for oral cancer diagnosis: What are the possibilities?

Oral cancer could be prevented. The primary strategy is based on prevention. Most patients with oral cancer present to the hospital network with advanced staging and a low chance of cure. This condition may be related to physicians' difficulty of making an early diagnosis. With the advancement of information technology, artificial intelligence (AI) holds great promise in terms of assisting in diagnosis. Few machine learning algorithms have been developed for this purpose to date. In this paper, we will discuss the possibilities for diagnosing oral cancer using AI as a tool, as well as the implications for the population. A set of photographic images of oral lesions has been segmented, indicating not only the area of the lesion but also the class of lesion associated with it. Different neural network architectures were trained with the goal of fine segmentation (pixel by pixel), classification of image crops, and classification of whole images based on the presence or absence of a lesion. The accuracy results are acceptable, opening up possibilities not only for identifying lesions but also for classifying the pathology associated with them.

Solvatochromic and ionochromic effects of Iron(II)bis(1,10-phenanthroline)dicyano: a theoretical study.

Solvatochromic and ionochromic effects of the iron(II)bis(1,10-phenanthroline)dicyano (Fe(phen)(2)(CN)(2)) complex were investigated by means of combined DFT/TDDFT calculations using the PBE and B3LYP functionals. Extended solvation models of Fe(phen)(2)(CN)(2) in acetonitrile and aqueous solution, as well as including interaction with Mg(2+), were constructed. The calculated vertical excitation energies reproduce well the observed solvatochromism in acetonitrile and aqueous solutions, the ionochromism in acetonitrile in the presence of Mg(2+), and the absence of ionochromic effect in aqueous solution. The vertical excitation energies and the nature of the transitions were reliably predicted after inclusion of geometry relaxation upon aqueous micro- and global solvation and solvent polarization effect in the TDDFT calculations. The two intense UV-vis absorption bands occurring for all systems studied are interpreted as transitions from a hybrid Fe(II)(d)/cyano N(p) orbital to a phenanthroline pi* orbital rather than a pure metal-to-ligand-charge transfer (MLCT). The solvatochromic and ionochromic blue band shifts of Fe(phen)(2)(CN)(2) were explained with preferential stabilization of the highest occupied Fe(II)(d)/cyano N(p) orbitals as a result of specific interactions with water solvent molecules or Mg(2+) ions in solution. Such interactions occur through the CN(-) groups in the complex, and they have a decisive role for the observed blue shifts of UV-vis absorption bands.

Comparison between two methods for cardiac output measurement in propofol-anesthetized dogs: thermodilution and Doppler.

OBJECTIVE: To compare cardiac output (CO) measured by Doppler echocardiography and thermodilution techniques in spontaneously breathing dogs during continuous infusion of propofol. To do so, CO was obtained using the thermodilution method (CO(TD)) and Doppler evaluation of pulmonary flow (CO(DP)) and aortic flow (CO(DA)). STUDY DESIGN: Prospective cohort study. ANIMALS: Eight adult dogs weighing 8.3 +/- 2.0 kg. METHODS: Propofol was used for induction (7.5 +/- 1.9 mg kg(-1) IV) followed by a continuous rate infusion at 0.7 mg kg(-1) minute(-1). The animals were positioned in left lateral recumbency on an echocardiography table that allowed for positioning of the transducer at the 3rd and 5th intercostal spaces of the left hemithorax for Doppler evaluation of pulmonary and aortic valves, respectively. CO(DP) and CO(DA) were calculated from pulmonary and aortic velocity spectra, respectively. A pulmonary artery catheter was inserted via the jugular vein and positioned inside the lumen of the pulmonary artery in order to evaluate CO(TD). The first measurement of CO(TD), CO(DP) and CO(DA) was performed 30 minutes after beginning continuous infusion (T0) and then at 15-minute intervals (T15, T30, T45 and T60). Numeric data were submitted to two-way anova for repeated measurements, Pearson's correlation coefficient and Bland & Altman analysis. Data are presented as mean +/- SD. RESULTS: At T0, CO(TD) was lower than CO(DA). CO(DA) was higher than CO(TD) and CO(DP) at T30, T45 and T60. The difference between the CO(TD) and CO(DP), when all data were included, was -0.04 +/- 0.22 L minute(-1) and Pearson's correlation coefficient (r) was 0.86. The difference between the CO(TD) and CO(DA) was -0.87 +/- 0.54 L minute(-1) and r = 0.69. For CO(TD) and CO(DP), the difference was -0.82 +/- 0.59 L minute(-1) and r = 0.61. CONCLUSION: Doppler evaluation of pulmonary flow was a clinically acceptable method for assessing the CO in propofol-anesthetized dogs.

Tomographic study of Jaw bone changes in patients with bisphosphonate-related osteonecrosis.

BACKGROUND: Bisphosphonates (BP) are synthetic pyrophosphate-like substances with antiresorptive properties and specifically affect osteoclastic activity. In 2007, the American Association of Oral and Maxillofacial Surgeons (AAOMS) defined diagnostic criteria for Osteonecrosis of the Jaws Associated with Bisphosponates (BRONJ). BRONJ is mainly diagnosed by clinical features, but the detection of early bone changes by imaging may help prevent and better understand the disease. The objective of this study was to evaluate maxillary changes in CBCT in patients using BP. MATERIAL AND METHODS: All included patients were diagnosed with osteonecrosis and received bisphosphonate drugs in the last ten years. All imaging examinations were obtained by I-CAT and 3D Accuitomo. The multiplanar reconstructions were analyzed by an examiner without knowledge of the clinical aspects and location of the lesions. RESULTS: The study sample consisted of 21 patients, the majority of the sample represented patients with cancer (76.2%), the other patients had osteoporosis (23.8%). Only four patients (19.04%) received alendronate, while intravenous bisphosphonates, such as zoledronate and pamidronate, represented the treatment of most of our sample. Most of our patients presented stage 1 and 2 MRONJ (85.7%), whose lesions were mainly observed in the mandible (52.4%). Fifty-seven percent of the patients had at least one bone change. CONCLUSIONS: In BRONJ, bone changes vary between exposed and non-exposed areas and one aspect of the study was: persistent extraction cavities in the BRONJ lesion region and high frequency of periodontal ligament space widening in areas that are not involved in BRONJ lesions. This reflects the very important role of dental and periodontal diseases in the pathophysiology of BRONJ. Thus, preventive measures should be prioritized for patients exposed to anti-resorptive drugs. Key words:Cone-Beam computed tomography, osteonecrosis, bisphosphonate-associated osteonecrosis of the jaw.

Conventional Echocardiography and Two-Dimensional Speckle Tracking in Healthy Sevoflurane-Anesthetized Dogs Undergoing Continuous Rate Infusion of Nalbuphine.

Nalbuphine is an agonist-antagonist opioid with adequate analgesic properties and few depressant effects on the respiratory system. However, there are no detailed reports available on cardiovascular effects of nalbuphine in dogs. The aim of this study was to assess the effects of a continuous rate infusion (CRI) of nalbuphine on left ventricular systolic and diastolic function of healthy sevoflurane-anesthetized dogs. Eighteen mixed-breed bitches aged 1-4 years and weighing 9.9 ± 3.8 kg were used. Dogs were randomly assigned to one of two groups: nalbuphine (GN, n = 9) and control (GC, n = 9). Anesthesia was induced and maintained with sevoflurane (2V%) followed by an intravenous (IV) bolus of nalbuphine (0.3 mg/kg) or 0.9% NaCl at equal volume and then CRI of nalbuphine (0.4 mg/kg/h) or 0.9% NaCl at an equal infusion rate. Echocardiographic and hemodynamic variables were determined at baseline and 20, 40, 60, and 80 minutes following start of CRI. No differences were found between groups for left ventricular systolic and diastolic variables obtained through conventional echocardiography and two-dimensional speckle tracking. Likewise, hemodynamic variables did not differ between groups. The E'/A' ratio significantly increased at 20 minutes compared to baseline only in GN. Nalbuphine given at a CRI does not influence left ventricular systolic and diastolic function in healthy sevoflurane-anesthetized dogs.

Spectroscopic, structural, and functional characterization of the alternative low-spin state of horse heart cytochrome C.

The alternative low-spin states of Fe(3+) and Fe(2+) cytochrome c induced by SDS or AOT/hexane reverse micelles exhibited the heme group in a less rhombic symmetry and were characterized by electron paramagnetic resonance, UV-visible, CD, magnetic CD, fluorescence, and Raman resonance. Consistent with the replacement of Met(80) by another strong field ligand at the sixth heme iron coordination position, Fe(3+) ALSScytc exhibited 1-nm Soret band blue shift and epsilon enhancement accompanied by disappearance of the 695-nm charge transfer band. The Raman resonance, CD, and magnetic CD spectra of Fe(3+) and Fe(2+) ALSScytc exhibited significant changes suggestive of alterations in the heme iron microenvironment and conformation and should not be assigned to unfold because the Trp(59) fluorescence remained quenched by the neighboring heme group. ALSScytc was obtained with His(33) and His(26) carboxyethoxylated horse cytochrome c and with tuna cytochrome c (His(33) replaced by Asn) pointing out Lys(79) as the probable heme iron ligand. Fe(3+) ALSScytc retained the capacity to cleave tert-butylhydroperoxide and to be reduced by dithiothreitol and diphenylacetaldehyde but not by ascorbate. Compatible with a more open heme crevice, ALSScytc exhibited a redox potential approximately 200 mV lower than the wild-type protein (+220 mV) and was more susceptible to the attack of free radicals.

Shielding of ionic interactions by sulfur dioxide in an ionic liquid.

The effect of adding SO2 on the structure and dynamics of 1-butyl-3-methylimidazolium bromide (BMIBr) was investigated by low-frequency Raman spectroscopy and molecular dynamics (MD) simulations. The MD simulations indicate that the long-range structure of neat BMIBr is disrupted resulting in a liquid with relatively low viscosity and high conductivity, but strong correlation of ionic motion persists in the BMIBr-SO2 mixture due to ionic pairing. Raman spectra within the 5

Reaction of a model siderophore with Ni(II), Co(II) and Zn(II) in aqueous solution: kinetics and spectroscopy.

A spectroscopic study was performed showing that the [Fe(III)(L(2-))(2)](1-) (L(2-)=dopacatecholate) complex reacts with Ni(II), Co(II) and Zn(II) in an aqueous solution containing S(2)O(3)(2-) resulting in the soluble [M(L(1-))(3)](1-) (L(1-)=dopasemiquinone; M=Ni(II), Co(II) or Zn(II) complex species. The Raman and IR spectra of the [CTA][M(L(1-))(3)] complexes, CTA=hexadecyltrimethylammonium cation, in the solid state were obtained. The kinetic constants for the metal substitution reactions were determined at four different temperatures, providing values for DeltaH(not equal), DeltaS(not equal) and DeltaG(not equal). The reactions were slow (k=10(-11) Ms(-1)) and endothermic. The system investigated can be considered as a simplified model to explain some aspects of siderophore chemistry.

Azo-hydrazone tautomerism in protonated aminoazobenzenes: resonance Raman spectroscopy and quantum-chemical calculations.

The protonation effect on the vibrational and electronic spectra of 4-aminoazobenzene and 4-(dimethylamino)azobenzene was investigated by resonance Raman spectroscopy, and the results were discussed on the basis of quantum-chemical calculations. Although this class of molecular systems has been investigated in the past concerning the azo-hydrazone tautomerism, the present work is the first to use CASSCF/CASPT2 calculations to unveil the structure of both tautomers as well the nature of the molecular orbitals involved in chromophoric moieties responsible for the resonance Raman enhancement patterns. More specifically both the resonance Raman and theoretical results show clearly that in the neutral species, the charge transfer transition involves mainly the azo moiety, whereas in the protonated forms there is a great difference, depending on the tautomer. In fact, for the azo tautomer the transition is similar to that observed in the corresponding neutral species, whereas in the hydrazone tautomer such a transition is much more delocalized due to the contribution of the quinoid structure. The characterization of protonated species and the understanding of the tautomerization mechanism are crucial for controlling molecular properties depending on the polarity and pH of the medium.

Spectroscopic investigation of conjugated polymers derived from nitroanilines.

For the first time, the resonance Raman spectroscopy was used to characterize polymers derived from meta- and para-nitroanilines. In order to improve the polymer structure analysis, other techniques were also used such as FTIR, UV-vis, XRD, XPS, EPR and N K-XANES. The insertion of strong electron-withdrawing groups (NO2) in polyaniline (PANI)-like backbone causes drastic changes in the lower energy charge transfer states, related to the polymer effective conjugation length. The resonance Raman data show that the NO2 moiety has a minor contribution on the CT state in poly(meta-nitroaniline), PMN, while in the poly(para-nitroaniline), PPN, the quinoid structure induced by para-substitution increases the charge density of NO2 groups, causing a more localized chromophore. The characterization of the imine nitrogen and of the protonated segments was done by XPS, N K-XANES and EPR spectroscopies and the lower polymerization degree of PPN, in comparison to PMN, is confirmed by XRD and TG data.

Raman, IR, UV-vis and EPR characterization of two copper dioxolene complexes derived from L-dopa and dopamine.

The anionic complexes [Cu(L(1-))3](1-), L(-)=dopasemiquinone or L-dopasemiquinone, were prepared and characterized. The complexes are stable in aqueous solution showing intense absorption bands at ca. 605 nm for Cu(II)-L-dopasemiquinone and at ca. 595 nm for Cu(II)-dopasemiquinone in the UV-vis spectra, that can be assigned to intraligand transitions. Noradrenaline and adrenaline, under the same reaction conditions, did not yield Cu-complexes, despite the bands in the UV region showing that noradrenaline and adrenaline were oxidized during the process. The complexes display a resonance Raman effect, and the most enhanced bands involve ring modes and particularly the nuCC+nuCO stretching mode at ca. 1384 cm(-1). The free radical nature of the ligands and the oxidation state of the Cu(II) were confirmed by the EPR spectra that display absorptions assigned to organic radicals with g=2.0005 and g=2.0923, and for Cu(II) with g=2.008 and g=2.0897 for L-dopasemiquinone and dopasemiquinone, respectively. The possibility that dopamine and L-dopa can form stable and aqueous-soluble copper complexes at neutral pH, whereas noradrenaline and adrenaline cannot, may be important in understanding how Cu(II)-dopamine crosses the cellular membrane as proposed in the literature to explain the role of copper in Wilson disease.

Green Teeth Related to Bilirubin Levels.

OBJECTIVE: To describe a form of tooth pigmentation caused by serum bilirubin deposition during dental calcification in a premature child. The bilirubin levels during the three months after birth are presented. In this period the crowns of the primary teeth are still forming. Such anomaly does not have symptoms, but has a displeasing effect and great anxiety within the family. CASE REPORT: The case reported here highlights the relevance of past medical history, especially the diagnoses of prolonged conjugated hyperbilirubinemia, in this case, to confirm them and to comfort the family. In this case, no esthetic treatment had been undertaken because the child was still too young and not yet concerned. The dental treatment plan included regular checkups every 3 months for maintaining oral health to prevent caries. CONCLUSION: As this is a rare condition that affects the teeth, parents will most likely look for a dentist for treatment. Therefore, dentists must be aware or such abnormalities and take a multidisciplinary approach, thus making it possible to establish a final diagnosis.