Is ChatGPT a reliable source of scientific information regarding third-molar surgery?

BACKGROUND

ChatGPT (OpenAI) is a large language model. This model uses artificial intelligence and machine learning techniques to generate humanlike language and responses, even to complex questions. The authors aimed to assess the reliability of responses provided via ChatGPT and evaluate its trustworthiness as a means of obtaining information about third-molar surgery.

METHODS

The authors assessed the 10 most frequently asked questions about mandibular third-molar extraction. A validated questionnaire (Chatbot Usability Questionnaire) was used and 2 oral and maxillofacial surgeons compared the answers provided with the literature.

RESULTS

Most of the responses (90.63%) provided via the ChatGPT platform were considered safe and accurate and followed what was the stated in the English-language literature.

CONCLUSIONS

The ChatGPT platform offers accurate and scientifically backed answers to inquiries about third-molar surgical extraction, making it a dependable and easy-to-use resource for both patients and the general public. However, the platform should provide references with the responses to validate the information.

PRACTICAL IMPLICATIONS

Patients worldwide are exposed to reliable information sources. Oral surgeons and health care providers should always advise patients to be aware of the information source and that the ChatGPT platform offers a reliable solution.

Penetrating Orbital Trauma by Large Foreign Body: Case Series Study with Treatment Guidelines and Literature Review

Purpose

The present study aims to describe a case study of large penetrating orbital trauma and treatment guidelines associated with a review of English-language literature of large foreign bodies impacting the orbit from 1997 to 2020.

Patients and Methods

Five patients suffered large penetrating orbital trauma and required emergency surgical procedures.

Results

Together with this present study, a total of 33 cases were selected. The present work has data similar to the literature, and emergency surgical treatment was required in the majority of the cases.

Conclusion

Penetrating orbital trauma by large objects is a challenge. The initial assessment and treatment are fundamental to determine the case severity. The large foreign body should be surgically removed by a trained and experienced team in an advanced hospital unit as soon as possible to minimize visual, functional and aesthetic sequelae.

Ultrasound protocol in odontogenic infections: a new proposal

BACKGROUND

Point-of-care-ultrasound can be applied to preview a difficult airway, detect the presence of fluid collection, and soft-tissue edema, and guide the drainage location, although is rarely used. The purpose of this study is to validate a protocol for the assessment of these clinical features on patients with severe odontogenic infections.

MATERIAL AND METHODS

This was a single-group prospective cohort study (n=20) including patients with the diagnosis of deep-neck propagation of odontogenic infection. A transcervical linear high-frequency probe transducer (13-6 MHz) was used to scan the structures of the upper airway and the infectious collections. The drainage was guided by ultrasound and the patients were daily evaluated, according to the protocol. The data were extracted and the airway volume, midline deviation, and other important data such as length of hospital stay, dysphagia, voice alteration, raised floor of the mouth, dyspnea, and neck swelling were registered.

RESULTS

The ultrasound examination was correlated with multiple clinical findings, such as dyslalia (p=0,069), dysphagia (p=0,028), dyspnea (p=0,001), among others. This protocol has an advantage as it can be used at bedside evaluation, allowing the assessment of severe and unstable patients, and predicting the increase of the hospitalization time (p=0,019).

CONCLUSIONS

This protocol is reliable for the assessment of the upper airway, even in an emergency, predicting not only the severity of the clinical features but aids in the determination of the length of the hospitalization time.

Ultrasonography on the Early Postoperative Control of Severe Odontogenic Infections

The management of odontogenic infections remains an important segment of the oral-maxillofacial surgical practice. The implementation of ultrasonography (US) imaging for the diagnosis of head and neck infections increases the possibility of visualizing the abscess collections in the deep neck spaces of lateral pharyngeal, masticator, and submandibular areas. The US imaging can detect the presence of fluid collections and edema, which may indicate local inflammation. Signs of deeper infections, such as subcutaneous emphysema and perifascial fluid, may also be apparent via US imaging. We present a new technique that uses US imaging to evaluate the deep neck infections after drainage from the early postoperative time to determine the locations of the drains inside the collection area and the edema of adjacent tissues. This technique is less costly than computed tomography or magnetic resonance imaging and allows for early assessment of adjacent tissues, leading to an earlier extubation and reduced hospitalization time and costs.

What Do We Know About COVID-19?: Maxillofacial Surgeons Survey

Coronavírus disease 2019 (COVID-19) is a virus of mass dissemination, with an impact on international public health, leading to hospitalizations and death. The main symptoms of COVID-19 are fever, fatigue, dry cough; however, myalgia and dyspnea and the transmission routes include direct transmission by cough, sneeze, droplet inhalation, or contact transmission with the oral, nasal, or eye mucous membranes. The dental professionals are the main risk group to COVID-19 due to the transmission routes that are directly related to the dental practice. In addition, the oral and maxillofacial surgeons (OMFS) are even more exposed, due to increased contact with the population in hospitals and emergency services. OMFS should be able to identify a suspected case of COVID-19, its symptoms, risk groups, disease severity, laboratorial and computed tomography alterations, and treatment guidelines. In the present study, the authors performed a nationwide survey with Brazilian OMFS to evaluate the knowledge of these professionals about the pandemic status of the COVID-19. A total of 142 OMFS replied the survey and the results brings light to an incomparable health public problem that the OMFS in Brazil are no able to protect itself, diagnose the suspicious and probable cases, request and interpret the correct laboratorial examinations for the treatment of the COVID-19 patients.

Unusual mandible fracture caused by metallic spear: case report and literature review

Spear gun projectiles injuries are are very rare and are usually related to lack of attention during water- sports or fishing practices. This study aims to describe an unusual case of facial injury associated with a mandibular fracture after a spear gun shot. A 38-years-old man was admitted with a history of penetrating injury on the face caused by an accidental shot from a spear gun. After the initial stabilization and examination, the patient was taken to the surgical room for the removal of the projectile. The post-operative care was uneventful and the patient was discharged with no concerns, being in follow-up for one year with no signs of infection or malocclusion. The surgical procedure should be done as soon as possible and the removal of the spear must be done carefully, under direct vision, with or without surgical incisions. Major complications can occur after spear injuries, therefore, the patient must be observed in the postoperative period and should maintain follow up until the end of the rehabilitative process.

Supernumerary nasal tooth removed with a modified maxillary vestibular approach: case report and literature review

PURPOSE

The aim of this present study is to describe a case of supernumerary nasal tooth removed with a modified maxillary vestibular approach with subperiosteal dissection.

METHODS

Also, a review of English-language literature of supernumerary nasal teeth from 1959 to 2018 was performed.

RESULTS

This study demonstrated that the modified maxillary approach with subperiosteal intranasal dissection is a useful approach for the exposure and removal of teeth impacted in the floor of the nasal cavity. The advantage of its use versus the other techniques is the lower risk of complications and postoperative morbidity. The use of computed tomography is essential to determinate the position of the tooth and to help in the surgical planning.

CONCLUSIONS

The transoral approaches are more natural to the oral and maxillofacial surgeons than the transnasal or endoscopic ones.

Peripheral effects induced in BALB/c mice infected with DENV by the intracerebral route

The lack of an immunocompetent animal model for dengue mimicking the disease in humans is a limitation for advances in this field. Inoculation by intracerebral route of neuroadapted dengue strains in mice is normally lethal and provides a straightforward readout parameter for vaccine testing. However, systemic effects of infection and the immune response elicited in this model remain poorly described. In the present work, BALB/c mice infected by the intracerebral route with neuroadapted DENV2 exhibited several evidences of systemic involvement. DENV-inoculated mice presented virus infective particles in the brain followed by viremia, especially in late stages of infection. Infection induced cellular and humoral responses, with presence of activated T cells in spleen and blood, lymphocyte infiltration and tissue damages in brain and liver, and an increase in serum levels of some pro-inflammatory cytokines. Data highlighted an interplay between the central nervous system commitment and peripheral effects under this experimental condition.

DNA vaccines against dengue virus based on the ns1 gene: The influence of different signal sequences on the protein expression and its correlation to the immune response elicited in mice

We analyzed four DNA vaccines based on DENV-2 NS1: pcENS1, encoding the C-terminal from E protein plus the NS1 region; pcENS1ANC, similar to pcENS1 plus the N-terminal sequence from NS2a (ANC); pcTPANS1, coding the t-PA signal sequence fused to NS1; and pcTPANS1ANC, similar to pcTPANS1 plus the ANC sequence. The NS1 was detected in lysates and culture supernatants from pcTPANS1-, pcENS1- and pcENS1ANC-transfected cells and not in cells with pcTPANS1ANC. Only the pcENS1ANC leads the expression of NS1 in plasma membrane, confirming the importance of ANC sequence for targeting NS1 to cell surface. High levels of antibodies recognizing conformational epitopes of NS1 were induced in mice immunized with pcTPANS1 and pcENS1, while only few pcENS1ANC-inoculated animals presented detectable anti-NS1 IgG. Protection against DENV-2 was verified in pcTPANS1- and pcENS1-immunized mice, although the plasmid pcTPANS1 induced slight higher protective immunity. These plasmids seem to activate distinct patterns of the immune system.

Occurrence of toxin-producing cyanobacteria blooms in a Brazilian semiarid reservoir

We report the occurrence of cyanobacterial blooms and the presence of cyanotoxins in water samples from the Armando Ribeiro Gonçalves reservoir (06 degrees 08 S and 37 degrees 07 W), located in the state of Rio Grande do Norte, in the semiarid region of northeastern Brazil. The cyanobacterial species were identified and quantified during the rainy and dry seasons in the year 2000. Cyanotoxins such as microcystins, saxitoxins and cylindrospermopsins were analyzed and quantified using HPLC and ELISA methods. The mixed toxic blooms of Cylindrospermopsis raciborskii, Microcystis spp (M. panniformis, M. protocystis, M. novacekii) and Aphanizomenon spp (Aphanizomenon gracile, A. cf. manguinii, A. cf. issastschenkoi) were persistent and represented 90-100% of the total phytoplankton species. Toxic cyanobacterial blooms from the Armando Ribeiro Gonçalves reservoir were analyzed and found to have three phases in relation to the annual cycle. During the rainy season, an intense toxic bloom of Cylindrospermopsis raciborskii was recorded along with saxitoxins (3.14 microg.L(-1)). During the transition period, between the rainy and dry seasons, different species of Microscytis occurred and microcystin as high as 8.8 microg.L(-1) was recorded. In the dry season, co-dominance of Cylindrospermopsis raciborskii, Microcystis spp and Aphanizomenon spp occurred and the concentrations of saxitoxin remained very low. Our results indicate the presence of microcystins (8.8 microg.L(-1)) and saxitoxins (3.14 microg.L(-1)) into the crude water, with increasing concentrations from the second fortnight of April to late May 2000. The occurrence of toxic blooms in this reservoir points to a permanent risk of cyanotoxins in supply waters, indicating the need for the implementation of bloom control measures to improve the water quality. Exposure of the local population to cyanotoxins through their potential accumulation in fish muscle must also be considered.

Liver injury and viremia in mice infected with dengue-2 virus

The goal of this study was to test the feasibility of BALB/c mice as an experimental model in the study of dengue disease. BALB/c mice were intraperitoneal infected with DENV-2 obtained from a human patient. Histopathological analysis of infected animals revealed liver injury with viral antigens detection. In initial stages, the most prominent lesions were vacuolization and diffuse steatosis in hepatocytes. Serum levels of ALT and AST increased progressively, reaching the highest values 7 days p.i. and decreasing at the 14th day. Since levels of circulating virus were very low, viremia was analyzed in C6/36 cells. Virus presence was detected by ultrastructural analysis, confirmed by RT-PCR assays. Period of viremia was analyzed by flow cytometry with cells incubated with mouse-infected sera collected in different days, revealing peak virus levels at the 7th day p.i. All such data correlate to the development of the disease described in humans.

DNA vaccine against the non-structural 1 protein (NS1) of dengue 2 virus

Dengue is one of the most important mosquito-borne viral disease causing dengue fever and/or dengue shock syndrome/haemorrhagic fever. In some reports, the non-structural protein 1 (NS1) has been identified as a promising antigen for the development of vaccines against dengue virus (DENV). Apparently, it can elicit a protective antibody response with complement-fixing activities. In order to investigate the potential of a DNA vaccine based on the NS1 protein against DENV, we used the plasmid pcTPANS1, which contains the secretory signal sequence derived from human tissue plasminogen activator (t-PA) fused to the full length of the DENV-2 NS1 gene. All Balb/c mice intramuscularly inoculated with the pcTPANS1 presented high levels of NS1-specifc antibodies. Vaccinated animals were challenged with intracerebral DENV-2 virus inoculations and a 100% survival was observed. In general, results demonstrate that the pcTPANS1 plasmid is able to induce protection in mice, and then may be used as a vaccination approach against DENV in further assays.

Circulating human antibodies against dengue NS1 protein: potential of recombinant D2V-NS1 proteins in diagnostic tests

The dengue virus (DV) causes one of the most important arthropod-borne human viral diseases throughout the tropical and subtropical countries. However, the morbidity and mortality of DV infections could be reduced with an early hospitalization care and a rapid risk identification of developing the dengue haemorrhagic fever (DHF). The nonstructural glycoprotein 1 (NS1) has been pointed as a reagent for immune-assay diagnostic test optimization. To evaluate this potential, recombinant DV2-NS1 proteins (rNS1) were produced from Escherichia coli (NS1EC) and insect cells (NS1IC) expression. The tests were performed by analysis of a human serum panel reacted against different rNS1 forms. The results demonstrated high correspondence between the DV positive sera and the assay results using native or refolded forms of either NS1IC or NS1EC. Also, the IgG and IgM anti-rNS1 level profiles showed distinct distribution, depending on protein form and disease status. However, the IgM anti-rNS1 reactions did not show sensibility to detect the DV in primary infections. The data obtained from the paired serum samples reactivity comparison suggested a heterogeneous human immune response and absence of correspondence between the IgG and IgM profile levels. Moreover, a patient with negative reference test could be detected by specific IgG anti-rNS1 assays presented here. Therefore, these results sustain the usefulness of dengue nonstructural proteins, in particular the NS1, in diagnostic tests as a complementary reagent.

Histopathological aspects of Dengue-2 virus infected mice tissues and complementary virus isolation

The difficulty in studying dengue virus (DENV) infection in humans and in developing a virus vaccine is the absence of a suitable animal model which develops the full spectra of the Dengue haemorrhagic fever (DHF) and Dengue shock syndrome (DSS). Despite the fact that viruses have been found in various animal tissues, we isolated DENV from tissues of adult BALB/c mice, inoculated with DENV serotype 2 (DENV-2) obtained from human serum. Viruses were ultrastructurally identified and immunolocalized by immunofluorescence techniques in C6/36 mosquito cell cultures, inoculated with tissues (liver, lung, kidney and cerebellum) macerate supernatant from mice, 48 h post-infection (p.i.). These organs, collected at the same stage of infection, were examined histologically. The histopathological analysis revealed focal alterations in all tissues examined. Liver contained focal ballooned hepatocytes, but without modifying the average diameter of the majority of hepatocytes. Sinusoidal lumen was significantly diminished at this stage but portal and centrolobular veins became congested. Lungs exhibited hemorrhagic foci in the alveolar space, vascular congestion and focal alveolitis. Cerebellar tissue showed rare foci of neuronal compactation (Purkinje cells) and perivascular oedema. In kidneys it was observed an increase in glomerular volume with augmented endocapillary and mesangial cellularity, with reactivity to anti-IgM in all glomeruli of infected mice. In conclusion, DENV-2 was found in all tissues examined early in the evolution of infection. Presence of viruses in tissues has mainly led to hemodynamic alterations with generalized vascular congestion and increased permeability, and mast cell recruitment in lungs. The latter could participate in the vascular modifications in tissues.

Microcystins (cyanobacteria hepatotoxins) bioaccumulation in fish and crustaceans from Sepetiba Bay (Brasil, RJ)

Blooms of cyanobacteria in water bodies cause serious environmental problems and the occurrence of toxic strains are also related with the human health. Aquatic animals could bioaccumulate microcystins (cyanobacteria hepatotoxins) and so, beyond water, the ingestion of contaminated food represents a human health risk. Recently, WHO recommended a maximum concentration of microcystins (MCYSTs) in drinking water and established the tolerable daily intake (TDI) for consumption of cyanobacteria products contends MCYSTs (0.04 microg(-1) kg(-1) day(-1)). Sepetiba Bay is located in the municipal districts of Rio de Janeiro, Mangaratiba and Itaguai; being an important place of fishing activity. Due to the industrial development in the area, this bay is submitted to different environmental impacts, increasing the organic and industrial pollution. A strain of the nanoplanktonic cyanobacteria Synechocystis aquatilis f. aquatilis that produce MCYSTs was already isolated. In this study, we verified MCYSTs presence in muscle tissue of fish and crustaceans, which were harvested monthly in Sepetiba Bay during 11 months, in order to evaluate the potential risk of their ingestion. MCYSTs were analyzed by immunoassay techniques using the ELISA Microcystin Plate Kit (ENVIROLOGIX INC) and the concentration were expressed as microcystin-LR equivalent. The analyses of seston samples, water, muscle tissues showed the presence of this cyanotoxin in all samples and it was verified that 19% of the animals' samples were above the limit recommended by WHO for human consumption. The maximum value found was of 103.3 microg kg(-1) (TDI 0.52 microg kg(-1) day(-1)) and the minimum, was 0.25 microg kg(-1) in crabs muscle tissue (TDI of 0.001 microg kg(-1) day(-1)). Such data demonstrate that, although in low concentrations, there is already a contamination of fish and crustaceans from Sepetiba Bay. We highlight that the recommended limit refers to healthy adult.

Major amputations of the lower leg. The patients two years later

The most devastating consequence of vascular disease of the lower extremity is amputation. Although considered as the end of the efforts of the vascular procedures, it should not be considered the end of medical treatment of the patient. The purpose of this study was to determine the situation of patients who suffered a major amputation of the lower leg due to ischemic vascular disease, at least two years after this event.

PATIENTS AND METHODS

Forty-eight patients who had major amputation had their chart reviewed and were contacted to inform about the current conditions of rehabilitation. In case of death, the causes of dismissal were obtained. The degree of rehabilitation was compared to the preoperative level of selfishness.

RESULTS

Before amputation, 15 patients had an independent life, 21 could walk up to 500 meters, seven were confined to a wheel-chair or used crutches and five were bedridden. At least two years later, 54.2% of the patients died and only nine were fully rehabilitated (18.8% of all the patients and 40.9% of the living patients).

CONCLUSIONS

Patients who suffer amputation due to vascular disease do have a low survival rate after two years. Among the survivors, only few patients do have clinical conditions to regain a regular situation of autonomy.

Chemical constituents from Lippia sidoides and cytotoxic activity

Eleven known compounds and a new prenylated naphthoquinone, lippsidoquinone (13), were isolated from ethanol extracts of Lippia sidoides. Their structures were established by a combination of 1D and 2D NMR, IR, and EIMS spectral data analysis. The cytotoxic properties of compounds 3--13 were evaluated against HL60, SW1573, and CEM cell lines. Only tectol (6) and lippsidoquinone (13) exhibited significant activity against human leukemia cell lines HL60 and CEM.

Water in toluene revisited: vibrational patterns in the stretching region

The symmetric (v1) and antisymmetric (v3) stretching bands of water monomers in toluene are revisited using two approaches: (i) calculation of dipole autocorrelation functions (ii) the solvatochromic behaviour of both vibration frequency shifts. The time constants extracted from the autocorrelations account for meaningful differences between the couplings established by the antisymmetric and symmetric vibrations with the solvent. The dipole autocorrelation function for the symmetric stretching band fits well a Lorentzian spectral density and shows a higher contribution to hindered rotation relatively to the one obtained from the antisymmetric stretching. The spectral shifts of stretching frequencies in toluene and in other relevant solvents were interpreted as arising from the electronic and orientational polarisations. Characteristic donor/acceptor interactions also contribute to the red shift and were tested by using empirical solvent basicity scales such as Kamlet-Taft beta and the recently proposed SB. The deviations detected in toluene as regards the continuum dielectric predictions are quantitatively treated and account for the specific interaction between the water and the molecular pi electron system referred to in the literature.

A spectroscopic analysis of thermal stability of the Chromobacterium viscosum lipase

The thermal stability of the lipase from Chromobacterium viscosum was assessed by deactivation (loss of activity), fluorescence, circular dichroism (CD) and static light scattering (SLS) measurements. Lipase fluorescence emission is dominated by the tryptophyl contribution. An increase in the tyrosyl contribution from 2 to 16% was only observed upon prolonged incubation at 60 degrees C. The effect of temperature on the tryptophyl quantum yield was studied and two activation energies were calculated. Tryptophan residues in the native structure have an activation energy of 1.9 kcal mol(-1) for temperature-dependent non-radiative deactivation of the excited state. A structural change occurs at approximately 66.7 degrees C and the activation energy increases to 10.2 kcal mol(-1). This structural change is not characterized by tryptophan exposure on the surface of the protein. The deactivation and the evolution of structural changes with time after lipase incubation at 60 degrees C were assessed by fluorescence, CD and SLS measurements. CD spectra show that both secondary and tertiary structures remain native-like after incubation at 60 degrees C in spite of the fluorescence changes observed (red-shift from 330 to 336 nm on the trytophyl emission). SLS measurements together with the CD data show that deactivation may be due to protein association between native molecules. Deactivation and the decrease on the fraction of non-associated native lipase evaluated by changes in fluorescence intensity with time, show apparent first order kinetics. According to the rate constants, fluorescence changes precede deactivation pointing to an underestimation of the deactivation. Reactivation upon dilution during the activity assay and substrate-induced reactivation due to lipase interfacial adsorption are possible causes for this underestimation.

The location of tryptophan, N-acetyltryptophan and alpha-chymotrypsin in reverse micelles of AOT: a fluorescence study

The spectroscopic properties of alpha-chymotrypsin (alpha-Chym), L-tryptophan (Trp) and N-acetyl-L-tryptophan (NAT) solubilized in hydrated reverse micelles of sodium bis(2-ethylhexyl) sulfosuccinate in iso-octane were followed by fluorescence as a function of the amount of intramicellar water and initial pH. The lack of pH dependence observed for Trp in these systems, as opposed to what occurs in bulk water, and the similarities found for the protein in both media foresee different locations of these probes. In reverse micelles, fluorescence quenching studies using acrylamide emphasize the existence of structural alterations within the protein when its global charge changes from positive (pH = 7) to negative (pH = 10). The ensemble of the data points to an interfacial location of the zwitterionic Trp, an intermediate region of less tightly bound water for the location of the anionic Trp and NAT and an almost bulk water environment for alpha-Chym.

Effect of zeolite properties on ground-state and triplet-triplet absorption, prompt and oxygen induced delayed fluorescence of tetraphenylporphyrin at gas/solid interface

The ground-state and transient absorption, prompt and delayed fluorescence of tetraphenylporphyrin (TPP) adsorbed onto the external surface of different zeolites was monitored using diffuse-reflectance steady-state and laser flash photolysis. The delayed fluorescence (DF) of TPP detected in the presence of O2 is attributed to the energy transfer from 3TPP to 3O2 to form 1O2 and subsequent energy transfer from 1O2 to some other 3TPP within the organised molecular ensembles on the zeolite surface. The spectroscopic and kinetic parameters, namely the yield of DF (2-20% relative to prompt fluorescence), depend on the zeolite properties: the observed differences were correlated with the acid-base properties of the two zeolite series studied in this work (KA, NaA, CaA) and (NaA, NaX, NaY).

The role of molecular size in the excited state behavior of aminocoumarin dyes in restricted media--2: study of BC I in AOT-formamide reversed micelles

Ground and excited state properties of a pre-twisted 7-diethylaminocoumarin dye (BC I) belonging to the family of coumarinyl benzopyrano pyridines are reported in isooctane-AOT-formamide reversed micelles. In reversed micelles, BC I, albeit soluble in formamide, is found to remain out of the polar solvent pool. But the photophysical properties of the probe dye are sensitive to the changes in the polarity of the interfacial region caused by increase in F0 = [formamide]/[AOT]. The spectroscopic properties and dynamics are indicative of dual emission due to the solubilization of the dye in two different environments (the nonpolar solvent and the interfacial region). Results of the steady-state fluorescence anisotropy experiments also support the presence of two different environments. The present study once again proves that molecular size is an important parameter in the study of the photophysical properties of the flexible aminocoumarin dyes in reversed micelles.

[Down syndrome associated with clinical manifestations of Kabuki syndrome: report of a case]

OBJECTIVE: To describe an atypical case of Down syndrome presenting with additional clinical manifestations that might be components of Kabuki (Niikawa-Kuroki) syndrome.CLINICAL REPORT: We report the clinical history of a 19-month-old girl with a 47,XX, +21 karyotype, who presented brachycephaly, flat face, long palpebral fissures, eversion of the lateral portion of the lower eyelids, arched eyebrows with sparse lateral regions, long eyelashes, epicanthus, cortical cataract, small ears, protruding tongue, muscular hypotonia, developmental delay, hyperflexibility of joints, brachydactyly, and dermatoglyphic abnormalities.CONCLUSION: The diagnosis of Down syndrome was confirmed cytogenetically. However, the presence of additional anomalies - mainly in the ocular region - suggested that the child might also have the Kabuki syndrome.

Deactivation and conformational changes of cutinase in reverse micelles

Deactivation data and fluorescence intensity changes were used to probe functional and structural stability of cutinase in reverse micelles. A fast deactivation of cutinase in anionic (AOT) reverse micelles occurs due to a reversible denaturation process. The deactivation and denaturation of cutinase is slower in small cationic (CTAB/1-hexanol) reverse micelles and does not occur when the size of the cationic reverse micellar water-pool is larger than cutinase. In both systems, activity loss and denaturation are coupled processes showing the same trend with time. Denaturation is probably caused by the interaction between the enzyme and the surfactant interface of the reversed micelle. When the size of the empty reversed micelle water-pool is smaller than cutinase (at W0 5, with W0 being the water:surfactant concentration ratio) a three-state model describes denaturation and deactivation with an intermediate conformational state existing on the path from native to denaturated cutinase. This intermediate was clearly detected by an increase in activity and shows only minor conformational changes relative to the native state. At W0 20, the size of the empty water-pool was larger than cutinase and the data was well described by a two-state model for both anionic and cationic reverse micelles. For AOT reverse micelles at W0 20, the intermediate state became a transient state and the deactivation and denaturation were described by a two-state model in which only native and denaturated cutinase were present. For CTAB/1-hexanol reverse micelles at W0 20, the native cutinase was in equilibrium with an intermediate state, which did not suffer denaturation. 1-Hexanol showed a stabilizing effect on cutinase in reverse micelles, contributing to the higher stabilities observed in the cationic CTAB/1-hexanol reverse micelles. Copyright 1998 John Wiley & Sons, Inc.

Thermal unfolding of proteins at high pH range studied by UV absorbance

This work describes a methodology to monitor protein unfolding by using the well known changes in tyrosine absorbance with the ionization of the side chain phenol group. It can be applied to proteins that are functionally active at pH values higher than 9.0 where the current UV differential spectroscopy technique can not be used. The simplicity and facility of the proposed methodology (only two absorbance measurements have to be acquired) can make it very useful namely for technological applications. Thermal unfolding of cutinase and alpha-chymotrypsin were followed using this methodology and the thermodynamic stability data were obtained assuming a two-state mechanism. The transition from the folded to the unfolded state was further confirmed by fluorescence maxima for both proteins proving the validity of the methodology based on UV measurements.

Hydrogen bonding in a non-steroidal anti-inflammatory drug--Naproxen

Photophysical properties of a non-steroidal anti-inflammatory drug, Naproxen (6-methoxy alpha-methyl-2-naphthalene acetic acid sodium salt), were investigated in solvents of different polarity, hydrogen donor ability and also in cyclodextrins. The results indicate that in all cases the emitting state is the 1L(b) singlet. In alcoholic solvents, an intermolecular hydrogen bond is responsible for the observed photophysical behaviour of the probe whereas in non-protic solvents (polar and weakly polar) an intramolecular hydrogen bond type is postulated to rationalize the data found. In water, the non-radiative rate constant has a value similar to those found in aqueous solutions of alpha- and beta-cyclodextrins where the probe form complexes. The behaviour in water is explained by a water-structure enforced hydrophobic effect. The spectroscopic results are interpreted on the basis of a multiple-parameter model that considers specific solute-solvent interactions. These were also observed in the ground state and detected by Fourier transform infrared spectroscopy. Molecular mechanics (MM) and molecular orbital (AM1) calculations also support the existence of two conformations (rotamers) in Naproxen with non-equivalent intramolecular hydrogen bond-like formation.

Effect of proline administration on rat behavior in aversive and nonaversive tasks

Sustained levels of proline comparable to those of human type II hyperprolinemia were achieved in blood and brain of rats subcutaneous proline administration twice a day from the 6th till the 28th day of life. Control rats were treated with saline in the same volumes. Behavioral studies using aversive and nonaversive tasks were performed one week or one month after treatment. Proline treatment did not affect rats' performance in the inhibitory avoidance task, but reduced significantly habituation in the open field. Our results seem to indicate that early postnatal administration of proline to rats affects habituation to a novel environment. If this happens to be so the present tendency to consider hyperprolinemia as a benign condition should be revised.