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1.
Inorg Chem ; 63(15): 6649-6659, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38572737

RESUMO

Novel four-coordinated boron complexes (1-5) were synthesized via a reaction between BF3·CH3OH and benzimidazole-phenolate ligands (L1-L5), which are N,O-donors. These complexes exhibit intense blue emission in the solution and solid states accompanied by notable fluorescence quantum yields (ΦF). The study of the structure-property relation, through theoretical and experimental approaches, revealed a distinctive trend where compounds incorporating electron-donating substituents (methyl and ethoxy groups) in the phenolate moiety manifest shifts in emission wavelengths across the blue spectrum, concomitant with an increase in ΦF. Furthermore, the incorporation of an aromatic ring into the benzimidazole moiety considerably intensifies the rate of radiative relaxation from excited states. Notably, in the solid phase, either as a crystalline powder or loaded into polymer films, these modified complexes maintain or even surpass ΦF values observed in molecular solutions, ranging from 0.18 to 0.57, depending on the substitution. This characteristic makes these compounds attractive for applications in optoelectronics. All of the compounds were characterized using 1H, 13C, 11B, and 19F NMR, elemental analysis, and the molecular structures were corroborated through single-crystal X-ray diffraction analysis. Computational calculations via time-dependent density functional theory further elucidate the tunability of optical bandgaps through group substitution on ligands, aligning well with experimental observations.

2.
Clin Orthop Relat Res ; 482(2): 375-383, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37606954

RESUMO

BACKGROUND: Infection remains a serious clinical concern in patients with open fractures, despite timely antibiotic administration and surgical debridement. Soft tissue and periosteal stripping may alter local tissue homeostasis and antibiotic pharmacokinetics in the injured limb. The tissue (interstitial) concentration of intravenously administered antibiotics at an open fracture site has not been characterized using direct sampling techniques. QUESTION/PURPOSE: We performed this study to evaluate the concentration and pharmacokinetics of intravenously delivered cefazolin at an open fracture site after surgical debridement. METHODS: Twelve patients with an open fracture distal to the knee who presented at a regional Level I trauma center were approached for enrollment in this nonrandomized, observational study. Of the 12 patients, eight adults (one female, seven male) with a median age of 32 years (range 23 to 51 years) were enrolled and underwent successful sample collection for analysis. Three patients had incomplete datasets because of equipment malfunction and one elected not to participate. Seven patients had open tibia fractures, and one patient had an open fibula fracture associated with a closed tibia fracture. There were six Gustilo-Anderson Type II injuries and two Type IIIA injuries. Empiric antibiotics were administered in the prehospital setting or in the emergency department according to institutional protocol. When patients were taken to the operating room, a 2-g intravenous dose of cefazolin was administered. After surgical debridement, fracture stabilization, and wound closure, a microdialysis catheter was placed transdermally into the injury zone (within 5 cm of the fracture site) and a second catheter was placed in the contralateral uninjured (control) limb. Additional doses of cefazolin were administered every 8 hours postoperatively. Baseline and periodic interstitial fluid and whole blood (plasma) samples were collected in the operating room and at prespecified times for 24 hours postoperatively. Free cefazolin in the interstitial fluid and plasma samples were analyzed by ultra-high-performance liquid chromatography using C 18 column separation with quadrupole time-of-flight mass spectrometry detection. Data from the second postoperative dose of cefazolin were used to characterize pharmacokinetic parameters through a noncompartmental analysis using time-concentration curves of free cefazolin and assuming first-order elimination. For pharmacodynamic analyses, the modal cefazolin minimum inhibitory concentration (MIC) of Staphylococcus aureus (1 µg/mL) was used. RESULTS: With the samples available, no difference was observed in the median free cefazolin exposure over 24 hours ( f area under the curve [AUC] 0→24hrs ) between injured limbs (352 µg∙hr/mL [IQR 284 to 594 µg∙hr/mL]) and uninjured limbs (341 µg∙hr/mL [IQR 263 to 438 µg∙hr/mL]; p = 0.64). The median time to achieve the maximum concentration of free cefazolin ( f T max ) for injured limbs was delayed (2.7 hours [IQR 2.2 to 3.1 hours]) compared with control limbs (1.7 hours [IQR 1.2 to 2.0 hours]; p = 0.046). The time to the maximum concentration for plasma was not different from that of control limbs (p = 0.08). The time the cefazolin concentration was above the modal S. aureus MIC (T > MIC) in the injured and control limbs over 24 hours was 100% (IQR 100% to 100%) and 100% (IQR 97% to 100%), respectively. CONCLUSION: These preliminary findings suggest that current prophylactic cefazolin dosing regimens result in successful antibiotic delivery to the traumatized limb in moderately severe open fractures. Although cefazolin delivery to open-fracture wound beds was delayed compared with healthy tissues, the cefazolin concentration was sustained above the European Union Committee Antimicrobial Susceptibility Testing modal MIC for S. aureus , demonstrating a high likelihood of a prophylactic antimicrobial environment at an open fracture site with this empiric antimicrobial regimen. Importantly, patients in this analysis had Gustilo-Anderson Types II and IIIA injuries. Further research with a larger patient cohort is needed to determine whether antibiotic delivery to traumatized soft tissues in patients with higher-grade open fractures (Gustilo-Anderson Types IIIB and IIIC) demonstrates similar pharmacokinetic characteristics. LEVEL OF EVIDENCE: Level II, therapeutic study.


Assuntos
Fraturas Expostas , Fraturas da Tíbia , Adulto , Humanos , Masculino , Feminino , Adulto Jovem , Pessoa de Meia-Idade , Cefazolina , Fraturas Expostas/complicações , Infecção da Ferida Cirúrgica/etiologia , Staphylococcus aureus , Resultado do Tratamento , Estudos Retrospectivos , Antibacterianos , Fraturas da Tíbia/cirurgia , Fraturas da Tíbia/complicações , Extremidade Inferior
3.
Australas J Dermatol ; 64(4): 537-543, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37823565

RESUMO

The terminology surrounding the clinical syndrome characterized by acute mucositis with minimal skin involvement has been a subject of debate over time. In recent years, terms such as mycoplasma-induced rash and mucositis and reactive infectious mucocutaneous eruption (RIME) have been introduced to encompass milder mucocutaneous diseases associated with respiratory infections, with implications for management and prognosis. We report the first case of recurrent RIME associated with Chlamydophila pneumoniae infection in an adult patient. RIME is likely underreported due to misclassification and a lack of testing for potential pathogens. Early recognition of recurrent RIME is of particular interest from the patient's perspective to reduce the frequency and duration of hospital admissions.


Assuntos
Chlamydophila pneumoniae , Exantema , Mucosite , Pneumonia por Mycoplasma , Humanos , Adulto , Mycoplasma pneumoniae , Mucosite/complicações , Exantema/etiologia , Síndrome , Pneumonia por Mycoplasma/complicações
4.
Zoo Biol ; 42(2): 223-230, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36163695

RESUMO

The study of rare or cryptic species in zoos can provide insights into natural history and behavior that would be difficult to obtain in the field. Such information can then be used to refine population assessment protocols and conservation management. The Bermuda skink (Plestiodon longirostris) is an endemic Critically Endangered lizard. Chester Zoo's successful conservation breeding program is working to safeguard, increase and reinforce skink populations in the wild. A key aim of this program is to develop our understanding of the behavior of this species. In this study, using 24 h video recordings, we examined the daily activity patterns, basking behavior and food preferences of four pairs of Bermuda skinks. The skinks displayed a bimodal pattern of activity and basking, which may have evolved to avoid the strength of the midday sun in exposed habitats in Bermuda. Captive Bermuda skinks appear to prefer a fruit-based diet to orthopteran prey. We also documented their reproductive behavior and compared it against two closely related species. Although there were many similarities between the courtship and mating behaviors of the three species, there was a significantly shorter period of cloacal contact in the Bermuda skink. Oophagia was also documented for the first time in this species. This knowledge has enabled the evaluation of the current ex-situ management practices of this species, filled gaps in knowledge that would be challenging to obtain in the field, and enabled the enhancement of both animal husbandry and reproductive success for the conservation breeding program.


Assuntos
Espécies em Perigo de Extinção , Lagartos , Animais , Conservação dos Recursos Naturais/métodos , Bermudas , Animais de Zoológico , Melhoramento Vegetal
5.
J Vis ; 22(13): 4, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36458960

RESUMO

Although steady fixation is a key aspect of a proper visual function, it is only subjectively assessed in young and uncooperative children. In the present study, we characterize the development of fixational behavior throughout childhood in a large group of healthy children 5 months of age and up, recruited in five geographically diverse sites. In order to do it, we examined 802 healthy children from April 2019 to February 2020. Their oculomotor behavior was analyzed by means of an automated digital system, based on eye-tracking technology. Oculomotor outcomes were gaze stability, fixation stability and duration of fixations (for both long and short fixational tasks), and saccadic reaction time. Ninety-nine percent of all recruited children were successfully examined. Fixational and saccadic performance improved with age throughout childhood, with more pronounced changes during the first 2 years of life. Gaze and fixation tended to be more stable with age (p < 0.001 for most the outcomes), and saccades tended to be faster. In a multivariate analysis, including age and ethnicity as independent variables and adjusting by data quality, age was related with most fixational outcomes. Our automated digital system and eye-tracking data allow us to quantitatively describe the development of oculomotor control during childhood, assess visual fixation and saccadic performance in children 5 months of age and up, and provide a normative reference of fixational outcomes for clinical practice.


Assuntos
Movimentos Sacádicos , Sensação , Criança , Humanos , Pré-Escolar , Tecnologia de Rastreamento Ocular , Fixação Ocular , Análise Multivariada
6.
Nat Mater ; 19(11): 1164-1168, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32632281

RESUMO

Photonic integrated circuits (PICs) operating at cryogenic temperatures are fundamental building blocks required to achieve scalable quantum computing and cryogenic computing technologies1,2. Silicon PICs have matured for room-temperature applications, but their cryogenic performance is limited by the absence of efficient low-temperature electro-optic modulation. Here we demonstrate electro-optic switching and modulation from room temperature down to 4 K by using the Pockels effect in integrated barium titanate (BaTiO3) devices3. We investigate the temperature dependence of the nonlinear optical properties of BaTiO3, showing an effective Pockels coefficient of 200 pm V-1 at 4 K. The fabricated devices show an electro-optic bandwidth of 30 GHz, ultralow-power tuning that is 109 times more efficient than thermal tuning, and high-speed data modulation at 20 Gbps. Our results demonstrate a missing component for cryogenic PICs, removing major roadblocks for the realization of cryogenic-compatible systems in the field of quantum computing, supercomputing and sensing, and for interfacing those systems with instrumentation at room temperature.

7.
Chemistry ; 27(33): 8468-8472, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-33880825

RESUMO

Iridabicycles [Ir{κ3 -N,C,O-(pyC(H)=C(C(O)Me)2 }(Cl)(L-L)](L-L=cod (cod=1,5-cyclooctadiene), 1 a; bipy (bipy=2,2'-bipyridine), 1 b) have been obtained by oxidative coordination of 3-(pyridine-2-yl-methylene)pentane-2,4-dione L1, to the complexes [{Ir(µ-Cl)(cod)}2 ] and [{Ir(µ-Cl)(coe)2 }2 ] (coe=cis-cyclooctene), the latter in the presence of bipy. Remarkably, cleavage of the C3 -C(O)Me bond of L1 has instead been achieved in the reaction with [Ir(Cl)(dmb)2 ] (dmb=2,3-dimethylbutadiene), yielding a compound formulated as [Ir{κ2 -N,C-(pyC(H)C(C(O)Me))}(CO)(µ-Cl)(Me)]2 , 2. Treatment of dimer 2 with DMSO or PMe3 produced the complexes[Ir{κ2 -N,C-(pyC(H)C(C(O)Me)}(CO)Cl(Me)L] (L=DMSO, 3 a; PMe3 , 3 b). Plausible mechanisms for the reactions leading to complexes 1 and 2 are proposed by means of DFT calculations.

8.
J Cutan Pathol ; 48(11): 1416-1422, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34164837

RESUMO

Pagetoid Bowen disease is a subtype of Bowen disease that accounts for 5% of Bowen disease. It is extremely rare for Bowen disease to appear on the nipple-areola complex, with only seven cases described in the previous literature. Of those seven cases, only one was of the pagetoid subtype. We report two cases of pagetoid Bowen disease on this location, one of them being the first case of pagetoid Bowen disease affecting the nipple reported to date. On this location, it is crucial to perform a meticulous differential diagnosis to rule out Paget disease, because of its contrasting therapeutic and prognostic implications. In order to do this, clinical and histopathological aspects must be considered. From a clinical point of view, previous literature has stated that nipple involvement can be a clue that points to Paget disease. However, one of our cases shows that this is not always true. Regarding histopathological analysis, a complete excision of the tumor might be necessary to observe clear features of Bowen disease, such as full-thickness atypia of the epidermis and intercellular bridges. An immunohistochemical panel comprising carcinoembryonic antigen, gross cystic disease fluid protein, epithelial membrane antigen, p63, CK34betaE12, periodic acid-Schiff, estrogen receptor, and progesterone receptor can be decisive in complicated cases.


Assuntos
Doença de Bowen/patologia , Neoplasias da Mama/patologia , Mamilos/patologia , Doença de Paget Mamária/patologia , Neoplasias Cutâneas/patologia , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Doença de Bowen/diagnóstico , Neoplasias da Mama/diagnóstico , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Doença de Paget Mamária/diagnóstico , Neoplasias Cutâneas/diagnóstico
9.
J Zoo Wildl Med ; 52(3): 1061-1073, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34687525

RESUMO

A retrospective study revealed seven cases of coelomic steatitis in adult tentacled snakes (Erpeton tentaculatum), including two males and five females, between May 2014 and August 2020. Common clinical signs included death after unusual floating, generalized weakness, inappetence, reduced body condition, coelomic distension, and reproductive pathology in females. Hematology of one specimen revealed marked monocytosis and lymphocytosis with mild heterophilia (chronic and active inflammation). Gross examination identified variable degrees of intracoelomic fat necrosis in all snakes. Consistent histopathologic features included necrotic adipocytes, lipid saponification, lipofuscin/ceroid deposition, granulomatous inflammation, and multinucleated giant cells (Langhans type). Three females exhibited intralesional yolk fluid associated with periovarian steatitis. Hepatic lipidosis was the second most frequent pathologic finding. Thawed frozen lesser sand eels (Ammodytes tobianus) were fed during this period, stored in vacuum-sealed or opened packets at -18°C (frozen). After the death of the last specimen, vitamin E concentrations and peroxide values of the diet were analyzed. For the sealed and opened frozen batches, respectively, vitamin E concentrations were 0.71 and 0.49 mg/100 g (compared with 4 to 8 mg/100 g in average, fresh, raw mixed eel species samples) and peroxide values were 62.5 and 48.6 meq/kg (exceeding the acceptable peroxide values of 8 meq/kg for fish oils). This case study represents the first report of coelomic steatitis in tentacled snakes of unconfirmed etiology but with a putative association with feeding a long-term frozen-stored sand eel diet containing low vitamin E concentrations and fish oils with high peroxide values at time of analysis.


Assuntos
Colubridae , Esteatite , Animais , Feminino , Masculino , Necrose/veterinária , Estudos Retrospectivos
10.
J Zoo Wildl Med ; 52(1): 133-144, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33827170

RESUMO

The mountain chicken frog (Leptodactylus fallax) is the largest endemic amphibian species in the Western Hemisphere. Since 1998, this critically endangered species has been maintained as a European Endangered Species Programme, but low breeding success and a high mortality rate threaten the sustainability of the captive frog population. In the current study, we analyzed gross and histopathologic postmortem information from 212 mountain chicken frogs that died in European zoological collections from 1998 to 2018. Thin body condition was the most commonly reported finding across all submissions, observed in 125 frogs. The gastrointestinal and urinary systems were reported to have the highest prevalence of pathologic findings on gross and histopathologic examination. Inflammatory disease was the most frequent diagnosis after histopathologic examination of relevant tissues, with intestinal inflammatory disease (n = 76) followed by tubulointerstitial nephritis (n = 26) being the most commonly reported. Neoplasia was reported in 42 of 212 (19.8%) frogs, all of which were adults. A defined cause of death, or reason for euthanasia, was proposed for 164 of 212 (77.4%) frogs, with inflammatory diseases processes (74 of 212; 34.9%) most commonly implicated. Intestinal adenocarcinoma, seemingly restricted to the colon, caused the deaths of 31 adult frogs. Further investigations to determine factors contributing to the high incidence of inflammatory disease processes and neoplasia are advocated to improve the health and sustainability of the captive mountain chicken frog population.


Assuntos
Anuros , Espécies em Perigo de Extinção , Gastroenteropatias/veterinária , Doenças Musculoesqueléticas/veterinária , Doenças Urológicas/veterinária , Animais , Animais de Zoológico , Doenças do Sistema Digestório/patologia , Doenças do Sistema Digestório/veterinária , Europa (Continente) , Gastroenteropatias/patologia , Doenças Musculoesqueléticas/patologia , Estudos Retrospectivos , Doenças Urológicas/patologia
11.
J Exp Biol ; 223(Pt 17)2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32748794

RESUMO

One of the most detrimental factors in the drastic decline of the critically endangered European eel (Anguilla anguilla) was the inadvertent introduction of the invasive nematode Anguillicoloides crassus Infection primarily affects the swimbladder, a gas-filled organ that enables the eel to control its depth in the water. A reduction in swimbladder function may be fatal for eel undergoing their spawning migration to the Sargasso Sea, a journey of over 5000 km. Although the physiological damage caused by this invasive parasite is well studied through the use of quantifiable gross pathological indices, providing a good measure of the swimbladder health status, they cannot separate the role of mechanical and morphological damage. Our study examined the appropriateness of three commonly used indices as a measure of mechanical damage by performing uniaxial tensile tests on swimbladder specimens obtained from an infected eel population. When the test results were compared with the gross pathological indices it was found that thickness correlated most strongly with mechanical damage, both confirming and, more importantly, explaining the counterintuitive findings of earlier work. In a damaged swimbladder, the immune response leads to a trade-off; increasing wall thickness raises the pressure required for organ rupture but decreases strength. The results indicate that for moderate infection the mechanical integrity of the swimbladder can be maintained. For severe infection, however, a reduction in mechanical integrity may reach a tipping point, thereby affecting the successful completion of their oceanic migration.


Assuntos
Anguilla , Dracunculoidea , Doenças dos Peixes , Infecções por Nematoides , Sacos Aéreos , Animais , Infecções por Nematoides/veterinária
12.
Environ Res ; 182: 108992, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31830696

RESUMO

Pharmaceuticals are used for the prevention or treatment of diseases, and due to their manufacturing process they are continuously released to water bodies. One of the pharmacological groups detected in aquatic environments is non-steroidal anti-inflammatory drugs (NSAIDs) at trace concentrations. This study evaluated the survival and malformation rate in oocytes and larvae of Cyprinus carpio (C. carpio) after exposure to different proportions of an industrial effluent. Initially, the industrial effluent was sampled from an NSAID manufacturing plant located in the city of Toluca, State of Mexico, subsequently the physicochemical characterization and determination of the concentration of chemical compounds present were carried out. On the other hand, the lethal concentration 50 (LC50) and the effective concentration 50 (EC50) were calculated to determine the teratogenic index (TI), as well as the alterations to the embryonic development and the teratogenic effects on oocytes and larvae of C. carpio at the following proportions of the industrial effluent: 0.1, 0.3, 0.5, 0.7, 0.9 and 1.1%, following the Test Guideline 236, which describes a Fish Embryo Acute Toxicity test, the exposure times were 12, 24, 48, 72 and 96 h post-fertilization. The contaminants detected were NaClO (2.6 mg L-1) and NSAIDs such as diclofenac, ibuprofen, naproxen and paracetamol in the range of 1.09-2.68 mg L-1. In this study the LC50 was 0.275%, the EC50 0.133% and the TI 2.068. Several malformations were observed in all proportions of the industrial effluent evaluated, however the most severe such as spina bifida and paravertebral hemorrhage were observed at the highest effluent proportion. The industrial effluent evaluated in this study represents a risk for organisms that are in contact with it, since it contains chemical compounds that induce embryotoxic and teratogenic effects as observed in oocytes and larvae of C. carpio.


Assuntos
Carpas , Resíduos Industriais , Teratogênicos , Poluentes Químicos da Água , Animais , Larva , México , Oócitos/efeitos dos fármacos , Teratogênicos/toxicidade , Poluentes Químicos da Água/toxicidade
13.
J Biomed Inform ; 94: 103206, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31077818

RESUMO

Over a decade ago, a new discipline called network medicine emerged as an approach to understand human diseases from a network theory point-of-view. Disease networks proved to be an intuitive and powerful way to reveal hidden connections among apparently unconnected biomedical entities such as diseases, physiological processes, signaling pathways, and genes. One of the fields that has benefited most from this improvement is the identification of new opportunities for the use of old drugs, known as drug repurposing. The importance of drug repurposing lies in the high costs and the prolonged time from target selection to regulatory approval of traditional drug development. In this document we analyze the evolution of disease network concept during the last decade and apply a data science pipeline approach to evaluate their functional units. As a result of this analysis, we obtain a list of the most commonly used functional units and the challenges that remain to be solved. This information can be very valuable for the generation of new prediction models based on disease networks.


Assuntos
Doença , Desenvolvimento de Medicamentos , Reposicionamento de Medicamentos , Humanos , Modelos Teóricos
14.
Clin Exp Hypertens ; 40(5): 452-460, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29115861

RESUMO

Rigorous nutritional care during early life leads to healthy adulthood. Cardiovascular and metabolic disorders, the most prevalent clinical challenges worldwide, are epidemiologically linked to poor nutritional habits throughout life. We aimed to understand whether postnatal overnutrition (PO) initiated during lactation affects metabolic markers and vascular function later in life. To test this hypothetical effect, we studied a PO Wistar rat model based on adjusting litter size at the third day of age to three pups and eight for the control group (C). Systemic parameters such as body weight and food intake were significantly increased in adult rats, measured up to 36 weeks. Moreover, fat mass, triglycerides, insulin and systolic blood pressure were all significantly increased in the PO group. Furthermore, we assessed whether these alterations would affect morphological and functional parameters in isolated vessels. Consistent with systemic alterations of the vasculature, contraction of thoracic aortic rings, determined by dose-response curves to norepinephrine (NE), was significantly reduced in PO rats. Histological stains revealed that the relative area of collagen was higher and the elastic fiber density was lower in the distal rings of PO rats. Altogether, our results highlight the critical importance of having a healthy neonatal nutrition to prevent harmful metabolic and vascular alterations during adulthood.


Assuntos
Aorta Torácica/patologia , Aorta Torácica/fisiopatologia , Músculo Liso Vascular/fisiopatologia , Hipernutrição/fisiopatologia , Adiposidade , Animais , Animais Recém-Nascidos , Pressão Sanguínea , Peso Corporal , Modelos Animais de Doenças , Ingestão de Alimentos , Feminino , Insulina/sangue , Lactação , Tamanho da Ninhada de Vivíparos , Masculino , Contração Muscular/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Norepinefrina/farmacologia , Ratos , Ratos Wistar , Sístole , Triglicerídeos/sangue , Vasoconstritores/farmacologia
15.
Zoo Biol ; 37(3): 196-205, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29655202

RESUMO

The Critically Endangered mountain chicken frog (Leptodactylus fallax) has undergone drastic population decline due to habitat loss, hunting, invasive species, and chytridiomycosis. In response, several partner institutions initiated a conservation breeding program. It is important to maintain the captive population in good health. Therefore the program partners have recommended establishment of protocols for health examination of the species, including body condition assessment. Visual body condition scoring is a useful means to assess body condition in zoo animals for which regular bodyweight measurements are impractical or associated with capture-related stress. In this study, the authors developed a visual body condition score for the mountain chicken frog based on an ordinal categorical scale from 1 to 5 (1 = lowest body condition, 5 = highest body condition) using anatomical features that vary with total body energy reserves. Veterinary staff, animal managers, keepers, researchers, and students subsequently used the body condition score to assign scores to 98 mountain chicken frogs (41 male, 57 female) aged between 8 months and 12 years housed in five zoos in the UK and Jersey between February and March 2016. Body condition scores showed moderate (rho = 0.54; males) to strong (rho = 0.6; females) correlation with the scaled mass index, an objective measure of total energy reserves. The majority of pairwise comparisons between scores showed slight to substantial intra-observer agreement (93.8%) and slight to almost perfect inter-observer agreement (97.2%). Cases of poor agreement were likely due to limited observer experience working with the species.


Assuntos
Criação de Animais Domésticos , Anuros/fisiologia , Composição Corporal , Bem-Estar do Animal , Animais , Animais de Zoológico , Espécies em Perigo de Extinção
16.
Proc Natl Acad Sci U S A ; 111(43): 15562-7, 2014 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-25313031

RESUMO

In a number of bacterial pathogens, the production of virulence factors is induced at 37 °C; this effect is often regulated by mRNA structures formed in the 5' untranslated region (UTR) that block translation initiation of genes at environmental temperatures. At 37 °C, the RNA structures become unstable and ribosomes gain access to their binding sites in the mRNAs. Pseudomonas aeruginosa is an important opportunistic pathogen and the expression of many of its virulence-associated traits is regulated by the quorum-sensing (QS) response, but the effect of temperature on virulence-factor expression is not well-understood. The aim of this work is the characterization of the molecular mechanism involved in thermoregulation of QS-dependent virulence-factor production. We demonstrate that traits that are dependent on the QS transcriptional regulator RhlR have a higher expression at 37 °C, correlating with a higher RhlR concentration as measured by Western blot. We also determined, using gene fusions and point mutations, that RhlR thermoregulation is a posttranscriptional effect dependent on an RNA thermometer of the ROSE (Repression Of heat-Shock gene Expression) family. This RNA element regulates the expression of the rhlAB operon, involved in rhamnolipid production, and of the downstream rhlR gene. We also identified a second functional thermometer in the 5' UTR of the lasI gene. We confirmed that these RNA thermometers are the main mechanism of thermoregulation of QS-dependent gene expression in P. aeruginosa using quantitative real-time PCR. This is the first description, to our knowledge, of a ROSE element regulating the expression of virulence traits and of an RNA thermometer controlling multiple genes in an operon through a polar effect.


Assuntos
Pseudomonas aeruginosa/patogenicidade , RNA Bacteriano/metabolismo , Temperatura , Fatores de Virulência/metabolismo , Regiões 5' não Traduzidas/genética , Proteínas de Bactérias/metabolismo , Sequência de Bases , Regulação Bacteriana da Expressão Gênica , Homosserina/análogos & derivados , Homosserina/metabolismo , Espaço Intracelular/metabolismo , Lactonas/metabolismo , Dados de Sequência Molecular , Óperon/genética , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/crescimento & desenvolvimento , Reação em Cadeia da Polimerase em Tempo Real , Sequências Reguladoras de Ácido Nucleico/genética , Transcrição Gênica
18.
J Food Sci Technol ; 54(4): 933-943, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28303044

RESUMO

Starches isolated from four ayocote bean varieties were modified by thermal treatment to determinate the effect of the treatment on the structural changes of ayocote bean starch. Scanning electron microscopy indicates that the starch granules have oval and round shapes, with heterogeneous sizes and fractures when the extraction method is used. The presence of new bands at 2850 and 1560 cm-1 in the FT-IR spectra showed that the thermal treatment of ayocote beans induced an interaction between the protein or lipid and the amylose or amylopectin, while the sharpest band at 3400 cm-1 indicated a dehydration process in the starch granule in addition to the presence of the band at 1260 cm-1, indicating the product of the retrogradation process. The thermal treatment reduced the crystallinity as well as short-range order. Raman spectroscopy revealed that acute changes occurred in the polysaccharide bonds after thermal treatment. This study showed that the thermal treatment affected the structural properties of ayocote bean starches, the interactions of the lipids and proteins with starch molecules and the retrogradation process of starch.

20.
Opt Express ; 24(8): 8797-808, 2016 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-27137314

RESUMO

In this work we report on a single photon detector system which offers near-unity detection efficiency using waveguide-coupled superconducting nanowires with lengths on the order of 1 µm. This is achieved by embedding the nanowires in a racetrack resonator where the interaction time with the photons trapped in the cavity is increased, thereby allowing for shorter nanowires. We expect this to lead to a higher fabrication yield as the amount of inhomogeneities decreases for shorter nanowires. Our simulations show a system with a 1 µm long superconducting nanowire single photon detector (SNSPD) operating at near-unity detection efficiency using design parameters that can be realistically achieved with conventional fabrication processes. The resonant cavity introduces spectral selectivity to the otherwise broad-band SNSPDs and the cavity induced timing jitter is shown to be insignificant for SNSPDs longer than 1 µm.

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