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1.
Vet Clin Pathol ; 53(2): 261-272, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38825585

RESUMO

BACKGROUND: Regenerating island-derived proteins (REG) are upregulated in people with sepsis, pancreatitis, and gastrointestinal diseases. One member of the REG family, namely REG3E, was recently identified in pancreatic tissue and plasma of dogs, with high expression in pancreatitis and sepsis. OBJECTIVES: We aimed to develop and validate an ELISA to measure REG3E concentrations in canine blood. METHODS: An indirect sandwich ELISA was developed using recombinant canine REG3E protein and polyclonal anti-canine REG3E antibodies raised in guinea pigs and rabbits. Antibody specificity was assessed using western blot and mass spectrometric analysis of protein purified from canine plasma. Assay validation included evaluation of dilutional linearity, parallelism, spiking recovery, repeatability and reproducibility, stability, interferences, and comparison of serum and heparinized plasma. RESULTS: Antibodies bound specifically to REG3E with no evidence of cross-reactivity with other proteins. The limit of detection of the ELISA was 15 ng/mL, and the lower limit of quantification was 30 ng/mL. The assay demonstrated good to excellent linearity, dilutional and mixing parallelism, and recovery, with mean observed-to-expected ratios of 104%, 107%, 102%, and 92%, respectively, and no evidence of a hook effect. Coefficients of variation were ≤8.5% for repeatability and ≤14.3% for reproducibility at three different levels. Measurements of REG3E in plasma were not significantly influenced by different storage conditions, freeze-thawing cycles, hemolysis, lipemia, or icterus. There was no significant difference between REG3E concentrations in heparinized plasma and serum samples. CONCLUSIONS: The canine REG3E ELISA has acceptable precision, accuracy, linearity, and reproducibility for the measurement of REG3E in canine plasma and serum.


Assuntos
Ensaio de Imunoadsorção Enzimática , Animais , Cães/sangue , Ensaio de Imunoadsorção Enzimática/veterinária , Reprodutibilidade dos Testes , Coelhos , Proteínas Associadas a Pancreatite/sangue , Proteínas Recombinantes
2.
J Comp Pathol ; 208: 42-44, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38141387

RESUMO

A 2-year-3-month-old female guinea pig (Cavia porcellus) was referred for lethargy, weight gain and severe abdominal pain. Ultrasound examination revealed thickening and enlargement of the left uterine horn and an unremarkable right uterine horn. The animal died during ovariohysterectomy due to respiratory and cardiac arrest. Necropsy revealed unilateral segmental uterine horn hypoplasia and aplasia of the fallopian tube of the corresponding side. This is the first report of a congenital uterine malformation in the guinea pig and we describe the clinical and pathological presentation of segmental uterine horn hypoplasia and fallopian tube aplasia. Congenital uterine malformations are rare in guinea pigs but should be considered as differential diagnoses for the more common acquired uteropathies.


Assuntos
Tubas Uterinas , Anormalidades Urogenitais , Cobaias , Feminino , Animais , Tubas Uterinas/anormalidades , Útero/anormalidades , Anormalidades Urogenitais/veterinária
3.
J Vet Intern Med ; 37(3): 1067-1076, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37013632

RESUMO

BACKGROUND: Hyperlipasemia has been reported in dogs with acute kidney injury (AKI) but associations with AKI severity, hemodialysis (HD) treatment, and outcome have not been extensively evaluated. OBJECTIVES: Investigate the prevalence and clinical relevance of hyperlipasemia in dogs with AKI, treated with and without HD. ANIMALS: Client-owned dogs (n = 125) with AKI. METHODS: Retrospective data extraction from medical records, including signalment, cause of AKI, duration of hospitalization, survival, plasma creatinine concentration, and 1,2-o-dilauryl-rac-glycero-3-glutaric acid-(6'-methyresorufin) ester (DGGR) lipase activity at admission and throughout hospitalization. RESULTS: A DGGR-lipase activity >3× the upper reference limit (URL) was found in 28.8% and 55.4% of dogs at admission and during hospitalization, respectively, but only 8.8% and 14.9% of dogs, respectively, were diagnosed with acute pancreatitis. Hyperlipasemia >10 × URL was observed in 32.7% of dogs during hospitalization. The DGGR-lipase activity was higher in dogs with International Renal Interest Society (IRIS) Grades 4-5 than Grades 1-3, but correlation between DGGR-lipase activity and creatinine concentration was poor (rs = .22; 95% confidence intervals [CI], 0.04-0.38). Treatment with HD was not associated with DGGR-lipase activity independent of IRIS grade. Survival to discharge and 30 days after admission was 65.6% and 59.6%, respectively. High IRIS grades (P = .03) and high DGGR-lipase activity at admission (P = .02) and during hospitalization (P = .003) were associated with nonsurvival. CONCLUSIONS AND CLINICAL IMPORTANCE: Hyperlipasemia is frequent and often marked in dogs with AKI despite only a minority being diagnosed with pancreatitis. Hyperlipasemia is associated with AKI severity but not independently with HD treatment. High IRIS grade and hyperlipasemia were associated with nonsurvival.


Assuntos
Injúria Renal Aguda , Doenças do Cão , Pancreatite , Cães , Animais , Pancreatite/complicações , Pancreatite/terapia , Pancreatite/veterinária , Estudos Retrospectivos , Creatinina , Doença Aguda , Injúria Renal Aguda/terapia , Injúria Renal Aguda/veterinária , Diálise Renal/veterinária , Lipase , Doenças do Cão/diagnóstico
4.
Front Vet Sci ; 9: 1010809, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36387376

RESUMO

Regenerating islet-derived protein (REG) 1A (aka pancreatic stone protein) and REG3A (aka pancreatitis-associated protein) are upregulated in humans with sepsis, pancreatitis, and gastrointestinal diseases, but little is known about this protein family in dogs. Our aim was to identify REG1 and REG3 family members in dogs. REG-family genes were computationally annotated in the canine genome and proteome, with verification of gene expression using publicly available RNA-seq data. The presence of the protein in canine pancreatic tissue and plasma was investigated with Western blot and immunohistochemistry, using anti-human REG1A and REG3A antibodies. Protein identity was confirmed with mass spectrometry. Two members of the REG3 subfamily were found in the canine genome, REG3E1 and REG3E2, both encoding for the same 176 AA protein, subsequently named REG3E. Anti-human REG3A antibodies demonstrated cross-reactivity with the canine REG3E protein in pancreas homogenates. In canine plasma, a protein band of approximately 17 kDa was apparent. Mass spectrometry confirmed this protein to be the product of the two annotated REG3E genes. Strong immunoreactivity to anti-human REG3A antibodies was found in sections of canine pancreas affected with acute pancreatitis, but it was weak in healthy pancreatic tissue. Recombinant canine REG3E protein underwent a selective trypsin digestion as described in other species. No evidence for the presence of a homolog of REG1A in dogs was found in any of the investigations. In conclusion, dogs express REG3E in the pancreas, whose role as biomarker merits further investigations. Homologs to human REG1A are not likely to exist in dogs.

5.
Vet Sci ; 9(4)2022 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-35448676

RESUMO

Different lipase assays have variable reported diagnostic accuracies for acute pancreatitis (AP) in dogs. The aims of this retrospective study were to evaluate optimal cutoffs for 1,2-o-dilauryl-rac-glycero-3-glutaric acid-(6'-methylresorufin) ester (DGGR)-lipase to predict diagnostic cutoffs of canine pancreas-specific lipase (cPL; IDEXX). DGGR-lipase activity and cPL from the same blood draw in 301 dogs with a variety of diseases were compared using Spearman's rank correlation, Cohen's kappa agreement, and receiver operating characteristic (ROC) curves. Activity of DGGR-lipase (10−15,616 U/L) and cPL concentrations (8.1−≥2000 µg/L) were highly correlated (rs = 0.91). Areas under the ROC curves (AUCs) to predict cPL >200 and ≥400 µg/L with DGGR-lipase were 0.97 and 0.99, with optimal cutoffs of 143 U/L (sensitivity (Se) 91.7%; specificity (Sp) 95.3%) and 205 U/L (Se 97.5%; Sp 96.4%), and Cohen's kappa agreements of 0.87 and 0.92, respectively. AUCs for a clinical diagnosis of AP, assigned to 87/301 dogs, with DGGR-lipase (0.75) and cPL (0.76) did not differ significantly (p = 0.48); optimal cutoffs were 161 U/L for DGGR (Se 67%; Sp 81%) and 235 µg/L for cPL (Se 68%; Sp 84%). To conclude, DGGR-lipase is a highly accurate predictor of cPL with a comparable performance when used to diagnose AP in dogs.

6.
Parasit Vectors ; 15(1): 19, 2022 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-34998440

RESUMO

BACKGROUND: Cytauxzoon spp. infection is believed to be a newly emerging tick-borne disease in felids in Europe, with three species of the haemoparasite having recently been differentiated in wild felids. In Switzerland, rare infections have been documented in domestic cats in the west and northwest of the country, the first of which was in 2014. The aims of the present study were: (i) to characterize a Cytauxzoon spp. hotspot in domestic cats in central Switzerland; (ii) to elucidate the geographic distribution of Cytauxzoon spp. in domestic cats in Switzerland; (iii) to assess suspected high-risk populations, such as stray and anaemic cats; and (iv) to investigate the newly emerging nature of the infection. Cytauxzoon spp. were further differentiated using mitochondrial gene sequencing. METHODS: The overall study included samples from 13 cats from two households in central Switzerland (study A), 881 cats from all regions of Switzerland (study B), 91 stray cats from a hotspot region in the northwest of Switzerland and 501 anaemic cats from across Switzerland (study C), and 65 Swiss domestic cats sampled in 2003 and 34 European wildcats from eastern France sampled in the period 1995-1996 (study D). The samples were analysed for Cytauxzoon spp. using real-time TaqMan quantitative PCR, and positive samples were subjected to 18S rRNA, cytochrome b (CytB) and cytochrome c oxidase subunit I (COI) gene sequencing. RESULTS: In study A, six of 13 cats from two neighbouring households in central Switzerland tested postive for Cytauxzoon spp.; two of the six infected cats died from bacterial infections. In studies B and C, only one of the 881 cats (0.1%; 95% confidence interval [CI]: 0-0.3%) in the countrywide survey and one of the 501 anaemic cats (0.2%; 95% CI: 0-0.6%) tested postive for Cytauxzoon spp. while eight of the 91 stray cats in the northwest of Switzerland tested positive (8.8%; 95% CI: 3.0-14.6%). In study D, Cytauxzoon spp. was detected in one of the 65 domestic cat samples from 2003 (1.5%; 95% CI: 0-4.5%) and in ten of the 34 European wildcat samples from 1995 to 1996 (29%; 95% CI: 14.2-44.7%). The isolates showed ≥ 98.6% sequence identities among the 18S rRNA, CytB and COI genes, respectively, and fell in the subclade Cytauxzoon europaeus based on CytB and COI gene phylogenetic analyses. CONCLUSIONS: The study challenges the newly emerging nature of Cytauxzoon spp. in central Europe and confirms that isolates from domestic cats in Switzerland and European wild felids belong to the same species.


Assuntos
Doenças do Gato/parasitologia , Felidae/parasitologia , Piroplasmida/isolamento & purificação , Infecções Protozoárias em Animais/parasitologia , Animais , Animais Selvagens , Doenças do Gato/epidemiologia , Gatos , Filogenia , Piroplasmida/classificação , Piroplasmida/genética , Reação em Cadeia da Polimerase/veterinária , Infecções Protozoárias em Animais/epidemiologia , Suíça/epidemiologia
7.
Acta Crystallogr C Struct Chem ; 77(Pt 12): 777-781, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34864720

RESUMO

The synthesis and structures of bis[4-amino-3,5-bis(pyridin-2-yl)-1,2,4-triazole-κ2N2,N3]bis(thiocyanato-κN)cobalt(II), [Co(NCS)2(C12H10N6)2] or Co(NCS)2(abpt)2, and bis[4-amino-3,5-bis(pyridin-2-yl)-1,2,4-triazole-κ2N2,N3]bis(thiocyanato-κN)nickel(II), [Ni(NCS)2(C12H10N6)2] or Ni(NCS)2(abpt)2, are reported. In both cases, two polymorphs, A and B, were identified and structurally characterized. For both polymorphs, the structures obtained with the different metals, i.e. CoII or NiII, were found to be isostructural. All of the structures contained an intramolecular N-H...N hydrogen bond, C-H...N interactions and π-π stacking interactions. No structural evidence was observed for a thermal spin crossover for either of the Co(NCS)2(abpt)2 polymorphs between 300 (2) and 120 (2) K.

8.
Acta Crystallogr C Struct Chem ; 77(Pt 10): 659-667, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34607989

RESUMO

The synthesis, single-crystal structures and chromic behaviour of three related Schiff bases, namely, (E)-2,4-di-tert-butyl-6-{[(4-fluorophenyl)imino]methyl}phenol, C21H26FNO, 1, (E)-2,4-di-tert-butyl-6-{[(4-chlorophenyl)imino]methyl}phenol, C21H26ClNO, 2, and (E)-6-{[(4-bromophenyl)imino]methyl}-2,4-di-tert-butylphenol, C21H26BrNO, 3, are reported. Two polymorphs of 1 were obtained, which were found to have different photochromic properties. Schiff bases 2 and 3 were found to be isostructural and underwent a phase transition upon cooling which was attributed to the dynamic disorder in one of the tert-butyl groups resolving at low temperature. All of the structures were found to exist in the enol rather than the keto form based on the C-O(H) and imine C=N bond lengths, and contained an intramolecular O-H...N hydrogen bond alongside weaker intermolecular C-H...O contacts.

9.
Chem Commun (Camb) ; 57(79): 10238-10241, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34528050

RESUMO

The crystal structure of the radical ferromagnet 1a at 2 K reveals a contraction in the unit cell c constant which, at the molecular level, translates into a decrease in slippage of the radical π-stacks and an increase in ferromagnetic exchange interactions along the stacking axis. The results of BS-DFT calculations using long-range corrected functionals are consistent with an overall ferromagnetic topology.

10.
J Vet Emerg Crit Care (San Antonio) ; 31(1): 32-42, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33108052

RESUMO

OBJECTIVE: To evaluate the effects of 6% hydroxyethyl starch 130/0.4 (HES) and a polyionic isotonic crystalloid (CRYS) on standard coagulation tests and rotational thromboelastometry (ROTEM) in dogs with spontaneous hemoperitoneum (SHP). DESIGN: Prospective randomized open-label clinical study. SETTING: University teaching hospital. ANIMALS: Forty-two client-owned dogs presented with SHP. INTERVENTIONS: Dogs diagnosed with SHP and hypovolemic shock were randomly allocated to receive HES (10 mL/kg, n = 22) or CRYS (30 mL/kg, n = 20) intravenously over 20 minutes for hemodynamic stabilization. MEASUREMENTS AND MAIN RESULTS: Parameters measured before (T0 ) and after (T1 ) treatment were HCT, platelet counts, prothrombin time, activated partial thromboplastin time, fibrinogen concentrations, and extrinsic activated (EXTEM), intrinsic activated (INTEM), and extrinsic activated with platelet inhibition ROTEM assays. Data were analyzed as absolute values and as the percentage change from T0 to T1 . No significant differences between groups were detected in any variable at T0 , and for HCT, platelet counts, prothrombin time, activated thromboplastin time, and fibrinogen concentrations at T1 . Clot formation time in EXTEM was significantly prolonged (P = 0.037), and maximum clot firmness was significantly decreased (P = 0.038) in the HES group compared to the CRYS group at T1 . The percentage change in EXTEM clotting time (P = 0.012) and INTEM clot formation time (P = 0.031) was greater after HES than CRYS. Lysis indices remained at 100% for all ROTEM assays in both groups. CONCLUSION: Compared to a 3-fold volume of CRYS, administration of HES was associated with impairment in ROTEM parameters in dogs with SHP, but no evidence of hyperfibrinolysis was detected.


Assuntos
Soluções Cristaloides/uso terapêutico , Doenças do Cão/tratamento farmacológico , Hemoperitônio/veterinária , Derivados de Hidroxietil Amido/uso terapêutico , Substitutos do Plasma/uso terapêutico , Animais , Coagulação Sanguínea/efeitos dos fármacos , Testes de Coagulação Sanguínea/veterinária , Soluções Cristaloides/administração & dosagem , Soluções Cristaloides/farmacologia , Cães , Feminino , Hemoperitônio/tratamento farmacológico , Derivados de Hidroxietil Amido/administração & dosagem , Derivados de Hidroxietil Amido/farmacologia , Infusões Intravenosas/veterinária , Masculino , Tempo de Tromboplastina Parcial/veterinária , Substitutos do Plasma/administração & dosagem , Substitutos do Plasma/farmacologia , Estudos Prospectivos , Tempo de Protrombina/veterinária , Tromboelastografia/veterinária
11.
Chemistry ; 27(2): 740-750, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-32812653

RESUMO

The spin crossover salt [Fe(bpp)2 ](isonicNO)2 ⋅ 2.4 H2 O (1⋅2.4 H2 O) (bpp=2,6-bis(pyrazol-3-yl)pyridine; isonicNO=isonicotinate N-oxide anion) exhibits a very abrupt spin crossover at T1/2 =274.4 K. This triggers a supramolecular linkage (H-bond) isomerization that responds reversibly towards light irradiation or temperature change. Isotopic effects in the thermomagnetic behavior reveal the importance of hydrogen bonds in defining the magnetic state. Further, the title compound can be reversibly dehydrated to afford 1, a material that also exhibits spin crossover coupled to H-bond isomerization, leading to strong kinetic effects in the thermomagnetic properties.

12.
Acta Crystallogr C Struct Chem ; 76(Pt 11): 1001-1004, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-33148875

RESUMO

A new polymorph of (E)-4-bromo-2-[(phenylimino)methyl]phenol, C13H10BrNO, is reported, together with a low-temperature structure determination of the previously published polymorph. Both polymorphs were found to have an intramolecular O-H...N hydrogen bond between the phenol OH group and the imine N atom, forming an S(6) ring. The crystals were observed to have different colours at room temperature, with the previously published polymorph being more orange and the new polymorph more yellow. The planarity of the molecule in the two polymorphs was found to be significantly different, with dihedral angles (Φ) between the two aromatic rings for the previously published `orange' polymorph of Φ = 1.8 (2)° at 120 K, while the new `yellow' polymorph had Φ = 45.6 (1)° at 150 K. It was also observed that both polymorphs displayed some degree of thermochromism and upon cooling the `orange' polymorph became more yellow, while the `yellow' polymorph became paler upon cooling.

13.
ACS Omega ; 5(40): 25993-26004, 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33073126

RESUMO

The physicochemical properties of highly stable supramolecular donor-acceptor (D-A) complexes of a bis(18-crown-6)azobenzene (weak π-donor) with a series of bis(ammonioalkyl) derivatives of viologen-like molecules (π-acceptors) in acetonitrile were studied using cyclic voltammetry, UV-vis absorption spectroscopy, 1H NMR spectroscopy, and density functional theory (DFT) calculations. The crystalline structures of the bis(crown)azobenzene and its complex with a bis(ammoniopropyl) derivative of 2,7-diazapyrene were determined by X-ray diffraction analysis. In solution, all of the supramolecular D-A complexes studied have a pseudocyclic structure owing to ditopic coordination of the ammonium groups of the acceptor to the crown ether moieties of the donor. These complexes show somewhat lower stability as compared with the previously studied complexes of the related derivative of stilbene (strong π-donor), which is explained by the relatively weak intermolecular charge-transfer (CT) interactions. Time-dependent DFT calculations predict that the low-energy CT transition in the D-A complex of the bis(crown)azobenzene with a bis(ammoniopropyl) derivative of 4,4'-bipyridine lies between the local ππ* and nπ* transitions of the azobenzene. The absorption band associated with the CT transition is indiscernible in the spectrum since it is overlapped with broad and more intense ππ* and nπ* bands. It was found that the E → Z photoisomerization quantum yield of the bis(crown)azobenzene decreases by almost an order of magnitude upon the complexation with the 4,4'-bipyridine derivative. This effect was tentatively attributed to the intermolecular electron transfer that occurs in the 1ππ* excited state of the azobenzene and competes with the 1ππ* → 1 nπ* internal conversion.

14.
J Vet Intern Med ; 34(6): 2319-2329, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32945588

RESUMO

BACKGROUND: Hyperlipasemia is frequent in critically ill people without evidence of acute pancreatitis (AP), and has been associated with increased morbidity and mortality. OBJECTIVE: To evaluate the prevalence of hyperlipasemia at admission and development of hyperlipasemia during hospitalization in critically ill dogs, explore factors associated with hyperlipasemia, and evaluate association with outcome. ANIMALS: Critically ill, client owned dogs (n = 1360), presented on emergency and admitted to the intensive care unit, that had 1,2-o-dilauryl-rac-glycero-3-glutaric acid-(6'-methylresorufin) ester (DGGR) lipase activity measured within 24 hours of admission. METHODS: Retrospective cross-sectional study of clinical and laboratory records. RESULTS: The DGGR lipase activity was increased >3× the upper reference limit at admission in 216/1360 (16%) dogs, of which 70/216 (32%) had a clinical diagnosis of AP. Other primary conditions associated with hyperlipasemia were renal, endocrine, and immune-mediated diseases, and upper airway obstruction. Predictors of hyperlipasemia at admission were prior glucocorticoid administration, vomiting and abdominal pain, increased age, plasma bilirubin and creatinine concentrations, and decreased hematocrit. Of dogs with repeat measurements, 78/345 (23%) had significantly increased lipase during hospitalization, of which 13/78 (17%) had a clinical diagnosis of AP. Other primary conditions associated with in-hospital hyperlipasemia were renal and immune-mediated disorders. Predictors of developing hyperlipasemia during hospitalization were hemodialysis events, increased plasma bilirubin and creatinine concentrations, and decreased hematocrit. Hyperlipasemia both at admission and during hospitalization was associated with longer hospitalization and higher mortality. CONCLUSIONS AND CLINICAL IMPORTANCE: Significant DGGR-hyperlipasemia is frequent in critically ill dogs and associated with a variety of nonpancreatic conditions and negative outcome.


Assuntos
Doenças do Cão , Pancreatite , Doença Aguda , Animais , Estado Terminal , Estudos Transversais , Doenças do Cão/epidemiologia , Cães , Pancreatite/epidemiologia , Pancreatite/veterinária , Prevalência , Estudos Retrospectivos
15.
Acta Crystallogr C Struct Chem ; 76(Pt 9): 927-931, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32887865

RESUMO

The synthesis and structures of three isoxazole-containing Schiff bases are reported, namely, (E)-2-{[(isoxazol-3-yl)imino]methyl}phenol, C10H8N2O2, (E)-2-{[(5-methylisoxazol-3-yl)imino]methyl}phenol, C11H10N2O2, and (E)-2,4-di-tert-butyl-6-{[(isoxazol-3-yl)imino]methyl}phenol, C18H24N2O2. All three structures contain an intramolecular O-H...N hydrogen bond, alongside weaker intermolecular C-H...N and C-H...O contacts. The C-O(H) and imine C=N bond lengths were consistent with structures existing in the enol rather than the keto form. Despite having dihedral angles <25°, none of the compounds were observed to be strongly thermochromic, unlike their anil counterparts; however, all three compounds showed a visible colour change upon irradiation with UV light.

16.
Chem Sci ; 11(11): 2987-2992, 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-34122800

RESUMO

Alternative ('repeat') determinations of organic crystal structures deposited in the Cambridge Structural Database are analysed to characterise the nature and magnitude of the differences between structure solutions obtained by diffraction methods. Of the 3132 structure pairs considered, over 20% exhibited local structural differences exceeding 0.25 Å. In most cases (about 83%), structural optimisation using density functional theory (DFT) resolved the differences. Many of the cases where distinct and chemically significant structural differences remained after optimisation involved differently positioned hydroxyl groups, with obvious implications for the correct description of hydrogen bonding. 1H and 13C chemical shifts from solid-state NMR experiments are proposed as an independent methodology in cases where DFT optimisation fails to resolve discrepancies.

17.
Chem Sci ; 12(3): 1038-1053, 2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34163870

RESUMO

The iron(ii) salt [Fe(bpp)2](isonicNO)2·HisonicNO·5H2O (1) (bpp = 2,6-bis(pyrazol-3-yl)pyridine; isonicNO = isonicotinate N-oxide anion) undergoes a partial spin crossover (SCO) with symmetry breaking at T 1 = 167 K to a mixed-spin phase (50% high-spin (HS), 50% low-spin (LS)) that is metastable below T 2 = 116 K. Annealing the compound at lower temperatures results in a 100% LS phase that differs from the initial HS phase in the formation of a hydrogen bond (HB) between two water molecules (O4W and O5W) of crystallisation. Neutron crystallography experiments have also evidenced a proton displacement inside a short strong hydrogen bond (SSHB) between two isonicNO anions. Both phenomena can also be detected in the mixed-spin phase. 1 undergoes a light-induced excited-state spin trapping (LIESST) of the 100% HS phase, with breaking of the O4W⋯O5W HB and the onset of proton static disorder in the SSHB, indicating the presence of a light-induced activation energy barrier for proton motion. This excited state shows a stepped relaxation at T 1(LIESST) = 68 K and T 2(LIESST) = 76 K. Photocrystallography measurements after the first relaxation step reveal a single Fe site with an intermediate geometry, resulting from the random distribution of the HS and LS sites throughout the lattice.

18.
Nanomaterials (Basel) ; 9(1)2019 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-30641896

RESUMO

The acylation of unsymmetrical N-benzylbispidinols in aromatic solvents without an external base led to the formation of supramolecular gels, which possess different thicknesses and degrees of stability depending on the substituents in para-positions of the benzylic group as well as on the nature of the acylating agent and of the solvent used. Structural features of the native gels as well as of their dried forms were studied by complementary techniques including Fourier-transform infrared (FTIR) and attenuated total reflection (ATR) spectroscopy, atomic force microscopy (AFM), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and small-angle X-ray scattering and diffraction (SAXS). Structures of the key crystalline compounds were established by X-ray diffraction. An analysis of the obtained data allowed speculation on the crucial structural and condition factors that governed the gel formation. The most important factors were as follows: (i) absence of base, either external or internal; (ii) presence of HCl; (iii) presence of carbonyl and hydroxyl groups to allow hydrogen bonding; and (iv) presence of two (hetero)aromatic rings at both sides of the molecule. The hydrogen bonding involving amide carbonyl, hydroxyl at position 9, and, very probably, ammonium N-H⁺ and Cl- anion appears to be responsible for the formation of infinite molecular chains required for the first step of gel formation. Subsequent lateral cooperation of molecular chains into fibers occurred, presumably, due to the aromatic π-π-stacking interactions. Supercritical carbon dioxide drying of the organogels gave rise to aerogels with morphologies different from that of air-dried samples.

19.
Vet Anim Sci ; 8: 100068, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32734085

RESUMO

Leptospirosis is endemic in Switzerland affecting a broad range of hosts. The aim of this study was to estimate the exposure of cats to Leptospira in Switzerland. Plasma samples from 107 outdoor cats with an array of clinical problems were tested via microscopic agglutination test for the presence of anti-leptospiral antibodies against 12 serovars of 9 serogroups. Using a reciprocal cut-off titre of 1:100, an overall seroprevalence of 10.3% (95%CI 5.2-17.7) was observed. Seroreactivity against serovars Bratislava (n = 6), Australis (2), Pomona (3) and Copenhageni (1) was detected with reciprocal titres ranging from 1:100 to 1:800. The serologic status of the cats was independent of the disease group (p = 0.62). These results show that cats in Switzerland are commonly exposed to Leptospira and confirm the importance of serogroup Australis in this region.

20.
Parasit Vectors ; 11(1): 292, 2018 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-29747680

RESUMO

BACKGROUND: Cytauxzoonosis is an emerging tick-borne disease of domestic and wild felids. Cytauxzoon felis induces severe and often fatal disease in domestic cats. In Europe, clinical and subclinical infections caused by Cytauxzoon sp. are described. We report the first cases of Cytauxzoon sp. infection in domestic cats in Switzerland. METHODS: Clinical and laboratory data and results of PCR analyses were collected from Cytauxzoon sp. PCR-positive cats and the cats followed for up to 851 days. RESULTS: The cases were three two-month old kittens from the same litter (Cases 1-3) and two adult domestic shorthair cats (Cases 4 and 5). The cats originated from the north-west and west of Switzerland. Cases 1-3 presented with moderate to severe regenerative anaemia and intraerythrocytic inclusions. Cytauxzoon sp. was confirmed by PCR and sequencing. The kittens made a clinical and haematological recovery after blood transfusion and/or treatment with azithromycin and atovaquone, but erythroparasitaemia persisted. Case 4 presented with severe non-regenerative anaemia. Case 5 was healthy and used as a blood donor for Case 4. Following blood transfusion, Case 4 showed intraerythrocytic inclusions, and Cytauxzoon sp. was confirmed in both Cases 4 and 5 using PCR and sequencing. Case 4 achieved clinical and haematological remission after treatment with azithromycin, atovaquone and immunosuppressive drugs. Eight months later, Case 4 was presented again with anaemia but tested Cytauxzoon sp. PCR-negative. Sequencing of 1637 bp of the 18S rRNA gene of Cytauxzoon sp. revealed 100% nucleotide sequence identity among isolates of Cases 1-3 and between isolates of Cases 4 and 5, and 99% sequence identity between isolates of all cases. Phylogenetic analysis revealed the closest relationship of the Swiss isolates to Cytauxzoon sp. isolates from domestic cats and wild felids from France, Spain and Romania and to Cytauxzoon manul from a Pallas's cat. CONCLUSIONS: This is the first report of Cytauxzoon sp. infection in domestic cats in Switzerland. It is also the first report of infection in very young kittens and transmission of Cytauxzoon sp. to an adult cat by transfusion of blood from an asymptomatic cat. The cats recovered but some developed chronic asymptomatic erythroparasitaemia for up to 28 months. Domestic cats may act as reservoirs for Cytauxzoon sp. in Europe and blood donor cats should be screened for this agent by PCR.


Assuntos
Animais Domésticos/parasitologia , Reservatórios de Doenças/veterinária , Piroplasmida/isolamento & purificação , Infecções Protozoárias em Animais/transmissão , Doenças Transmitidas por Carrapatos/veterinária , Reação Transfusional/parasitologia , Animais , Infecções Assintomáticas/epidemiologia , Doenças do Gato/epidemiologia , Doenças do Gato/parasitologia , Doenças do Gato/transmissão , Gatos , Reservatórios de Doenças/parasitologia , Feminino , Masculino , Filogenia , Piroplasmida/classificação , Piroplasmida/genética , Piroplasmida/fisiologia , Reação em Cadeia da Polimerase/veterinária , Infecções Protozoárias em Animais/epidemiologia , RNA Ribossômico 18S/genética , Suíça/epidemiologia , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/parasitologia
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