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1.
Aust Vet J ; 102(4): 187-199, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38114290

RESUMO

AIMS: Bovine respiratory disease (BRD) has serious impacts on dairy production and animal welfare. It is most commonly diagnosed based on clinical respiratory signs (CRS), but in recent years, thoracic ultrasonography (TUS) has emerged as a diagnostic tool with improved sensitivity and specificity. This study aimed to assess the alignment of BRD diagnoses based on a Clinical Respiratory Scoring Chart (CRSC) and weekly TUS findings throughout the progression of BRD of variable severity in preweaned Holstein dairy heifers. METHODS: A total of 60 calves on two farms were followed from the 2nd week of life through the 11th week of life and assessed on a weekly basis for CRS and lung consolidation via TUS. The alignment of BRD diagnoses based on CRSC scores and TUS findings was evaluated across disease progression (pre-consolidation, onset, chronic, or recovered) and severity (lobular or lobar lung consolidation) using receiver operator curves and area under the curves combined with Cohen's kappa (κ), sensitivity, and specificity. RESULTS: The diagnosis of BRD using CRSC scores ≥5 aligned best with the onset of lobar lung consolidation (>1 cm in width and full thickness). This equated to an acceptable level of discrimination (AUC = 0.76), fair agreement (κ = 0.37), and a sensitivity of 29% and specificity of 99%. Similarly, there was acceptable discrimination (AUC = 0.70) and fair agreement (κ = 0.33) between CRSC ≥5 and the onset of a less severe threshold of disease based on lobular (1-3 cm2 but not full thickness) or lobar consolidation. Discrimination remained acceptable (AUC = 0.71) with fair agreement (κ = 0.28) between CRSC scores ≥2 for nasal discharge and/or cough (spontaneous or induced) and the onset of lobar consolidation. However, sensitivity was <40% across comparisons and outside of the onset of disease there tended to be poor discrimination, slight agreement, and lowered sensitivity between CRS and TUS diagnoses of lobular or lobar consolidation (pre-consolidation, chronic, or recovered). Conversely, specificity was relatively high (≥92%) across comparisons suggesting that CRSC diagnoses indicative of BRD and associated lung consolidation tend to result in few false positive diagnoses and accurate identification of healthy animals. CONCLUSIONS AND CLINICAL RELEVANCE: Although we found the specificity of clinical signs for diagnosing lung consolidation to be ≥92% across all methods of TUS evaluations, the low levels of sensitivity dictate that clinical assessments lead to many false negative diagnoses. Consequently, depending on clinical signs alone to diagnose BRD within populations of dairy calves will likely result in overlooking a substantial proportion of subclinically affected animals that could inform the success of treatment and prevention protocols and guide management decisions.


Assuntos
Doenças dos Bovinos , Doenças Respiratórias , Animais , Bovinos , Feminino , Doenças Respiratórias/diagnóstico por imagem , Doenças Respiratórias/veterinária , Doenças dos Bovinos/diagnóstico por imagem , Sensibilidade e Especificidade , Ultrassonografia/veterinária
2.
PLoS One ; 17(12): e0278664, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36454999

RESUMO

Gastrointestinal (GI) disease is a major health concern in preweaned dairy calves. The objective of this fixed cohort study was to use RNA isolated from preweaned Holstein and Jersey heifer calf feces to study the molecular adaptations to variable clinical GI disease. The study was conducted on a commercial calf ranch in the western U.S. Enrolled calves were assessed twice daily for variations in demeanor, milk intake, and hydration. Fecal consistency scores were recorded at enrollment (day 1), and on the day (day 10) that a fecal sample was collected for differential gene expression (DGE). Calves with diarrhea on either day were classified as having either uncomplicated, localized GI disease (scours), or systemic GI disease (systemic enteritis). Eighty-four calves' fecal RNA was evaluated for DGE, of which 33 calves (n = 20 Holstein; n = 13 Jersey) were consistently healthy. The remaining 51 calves (n = 23 Holstein; n = 28 Jersey) experienced varying severity of GI disease during the sampling window. Genes of interest were related to the inflammatory response (i.e., IFNG, NFKB1, NOD2, TLR2, and TLR4) and cell membrane or cytoplasmic transport (i.e., AQP3, FABP2, KRT8 and SLC5A1). Breed-specific findings indicated that AQP3, IFNG, and TLR4 were upregulated in Holsteins with systemic enteritis, whereas KRT8 was downregulated in systemically affected Jerseys. Holsteins did not appear affected by scours aside from a tendency for DGE of toll-like receptors (TLRs) on the day of diarrhea. However, Jersey calves consistently demonstrated a tendency to upregulate IFNG, NFKB1, and TLR4 when affected with either scours or systemic enteritis. These findings were more pronounced in systemically affected Jersey calves and were observed as a delayed response to both scours and systemic enteritis. These findings support previous observations suggesting that Holstein calves may be better equipped than Jersey calves to rapidly fight pathogen invasion.


Assuntos
Gastroenteropatias , RNA , Bovinos , Animais , Feminino , Estudos de Coortes , Receptor 4 Toll-Like/genética , Fezes , Diarreia/genética , Diarreia/veterinária
3.
G Chir ; 28(5): 222-6, 2007 May.
Artigo em Italiano | MEDLINE | ID: mdl-17547790

RESUMO

The bone surgery has always used manual and rotary instruments. The biomedical engineering with ultrasound working principle has given a new surgery instruments, which allow a selective cutting action of bone tissue and the protection of soft tissue. Our case shows an uncommon clinical lesion surgically dangerous for the narrow adjoining of important anatomical structures as the lower alveolar artery and the lower alveolar nerve. The clinical result and recovery time go toward a smaller traumatic situation of this methodology of the cutting of bone tissue.


Assuntos
Doenças Mandibulares/cirurgia , Procedimentos Cirúrgicos Bucais/métodos , Eletricidade , Feminino , Humanos , Pessoa de Meia-Idade
4.
Minerva Stomatol ; 43(9): 403-8, 1994 Sep.
Artigo em Italiano | MEDLINE | ID: mdl-7816014

RESUMO

To elaborate any protocol treatment it is vitally important to start therapy with the aim of resolving the etiological factor in order to avoid the risk of recidivation. For this purpose the stages which have led to the loss of functional equilibrium must be traced backwards. The most striking symptoms of this damage are represented by the altered occlusal ratios, but the etiopathogenesis must be sought not only in occlusal causes but, more often, in dysmorphic, postural or neuro-muscular causes. It is necessary to start working backwards having restored the spatial position of the jaw in all three dimensions. In order to achieve this for the past three years the authors have routinely used an occlusal plate that they have perfected in the treatment of the majority of patients with dysfunctional syndrome of the stomatognathic apparatus. Over 70% of approximately 600 cases referred to the authors during the same period were treated in this way. The choice of these cases was conditioned by the facial typology of patients. In fact, these patients were characterised by a facial typology which tended to be hypo-divergent. This provoked a condition of "mandibular imprisonment" with an occlusal ratio which locks the jaw in a retruded position. This condition is identified by the authors as the factor that triggers the syndrome not only in those patients in which it is clearly possible to diagnose occlusal diagnosis, but also in those cases in which the pathogenetic motive has a number of causes, for example, poor posture and cases of dysmorphosis.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Transtornos Craniomandibulares/terapia , Oclusão Dentária Balanceada , Aparelhos Ortodônticos Funcionais , Humanos , Modelos Dentários , Desenho de Aparelho Ortodôntico , Palato , Síndrome
6.
J Biol Chem ; 267(13): 9236-40, 1992 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-1533626

RESUMO

The UDP-Glc:glycoprotein glucosyltransferase is a soluble protein of the endoplasmic reticulum that catalyzes the glucosylation of protein-linked, glucose-free, high mannose-type oligosaccharides. In vivo, the newly glucosylated compounds are immediately deglucosylated, presumably by glucosidase II. The glucosyltransferase has been purified to apparent homogeneity from rat liver. The enzyme appears to have a molecular weight of 150,000 and 270,000 under denaturing and native conditions, respectively. The pure enzyme shows an almost absolute requirement for Ca2+ ions and for UDP-Glc as sugar donor. The same as crude preparations, the pure enzyme synthesized Glc1 Man7-9GlcNAc2-protein from Man7-9GlcNAc2-protein. Denatured glycoproteins are glucosylated much more efficiently than native ones by the apparently homogeneous glucosyltransferase. Availability of the pure enzyme will allow testing the possible involvement of transient glucosylation of glycoproteins in the folding of glycoproteins and/or in the mechanism by which cells dispose of malfolded glycoproteins in the endoplasmic reticulum.


Assuntos
Glucosiltransferases/isolamento & purificação , Microssomos Hepáticos/enzimologia , Animais , Sequência de Carboidratos , Bovinos , Cromatografia Líquida , Eletroforese em Gel de Poliacrilamida , Feminino , Glucosiltransferases/metabolismo , Masculino , Dados de Sequência Molecular , Ratos
7.
Glycobiology ; 1(2): 155-61, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1840423

RESUMO

N-linked oligosaccharides devoid of glucose residues are transiently glucosylated directly from UDP-Glc in the endoplasmic reticulum. The reaction products have been identified, depending on the organisms, as protein-linked Glc1Man5-9GlcNAc2. Incubation of right side-sealed vesicles from rat liver with UDP-[14C]Glc, Ca2+ ions and denatured thyroglobulin led to the glucosylation of the macromolecule only when the vesicles had been disrupted previously by sonication or by the addition of detergents to the glucosylation mixture. Similarly, maximal glucosylation of denatured thyroglobulin required disruption of microsomal vesicles isolated from the protozoan Crithidia fasciculata. Treatment of the rat liver vesicles with trypsin led to the inactivation of the UDP-Glc:glycoprotein glucosyltransferase only when proteolysis was performed in the presence of detergents. The glycoprotein glucosylating activity could be solubilized upon sonication of right side-sealed vesicles in an isotonic medium, upon passage of them through a French press or by suspending the vesicles in an hypotonic medium. Moreover, the enzyme appeared in the aqueous phase when the vesicles were submitted to a Triton X-114/water partition. Solubilization was not due to proteolysis of a membrane-bound enzyme. The enzyme could also be solubilized from C. fasciculata microsomal vesicles by procedures not involving membrane disassembly. About 30% of endogenous glycoproteins glucosylated upon incubation of intact rat liver microsomal vesicles with UDP-[14C]GLc could be solubilized by sonication or by suspending the vesicles in 0.1 M Na2CO3. These and previous results show that the UDP-Glc:glycoprotein glucosyltransferase is a soluble protein present in the lumen of the endoplasmic reticulum. In addition, both soluble and membrane-bound glycoproteins may be glucosylated by the glycoprotein glucosylating activity.


Assuntos
Retículo Endoplasmático/enzimologia , Glucosiltransferases/metabolismo , Microssomos Hepáticos/enzimologia , Animais , Crithidia fasciculata/enzimologia , Detergentes , Glucosiltransferases/isolamento & purificação , Glicoproteínas/metabolismo , Cinética , Octoxinol , Polietilenoglicóis , Ratos , Especificidade por Substrato , Tireoglobulina/metabolismo
8.
J Biol Chem ; 263(33): 17360-5, 1988 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-3053710

RESUMO

We have previously reported that the oligosaccharides transferred in vivo from dolichol-P-P derivatives in protein N-glycosylation in trypanosomatids are devoid of glucose residues and contain 2 N-acetylglucosamine and 6, 7, or 9 mannose units depending on the species. In this respect trypanosomatids differ from wild type mammalian, plant, insect, and fungal cells in which Glc3Man9GlcNAc2 is transferred. We are now reporting that incubation of Glc1-3Man9GlcNAc2-P-P-dolichol and Man7-9GlcNAc2-P-P-dolichol with membranes of Trypanosoma cruzi, Leptomonas samueli, Crithidia fasciculata, and Blastocrithidia culicis and an acceptor hexapeptide leads to the transfer of the six above mentioned lipid-linked oligosaccharides at the same rate. Control experiments performed under similar conditions but with rat liver and Saccharomyces cerevisiae membranes showed that, as already known, Glc3Man9GlcNAc2 is preferentially transferred in the latter systems. We have also previously reported that, once transferred to protein, the oligosaccharides become transiently glucosylated in trypanosomatids. Depending on the species, protein-linked Glc1Man5-9GlcNAc2 have been transiently detected in cells incubated with [14C] glucose. We are now reporting that glucosidase activities degrading both Glc1Man9GlcNAc2 and Glc2Man9GlcNAc2 were detected in T. cruzi, L. samueli, and C. fasciculata. The enzymatic activities were associated with a membrane fraction; they had a neutral optimum pH value, and similarly to mammalian glucosidase II, the enzyme acting on the monoglucosylated substrate showed a decreased affinity when the latter contained fewer mannose residues. No glucosidase I-like enzyme acting on Glc3Man9GlcNAc2 was detected in any of the three above-mentioned protozoan species. This result is consistent with the fact that no oligosaccharides containing 3 glucose units occur in trypanosomatids.


Assuntos
Eucariotos/enzimologia , Glucosidases/metabolismo , Glicoproteínas/genética , Hexosiltransferases , Proteínas de Membrana , Processamento de Proteína Pós-Traducional , Transferases/metabolismo , Animais , Cinética , Fígado/enzimologia , Oligossacarídeos de Poli-Isoprenil Fosfato/metabolismo , Ratos , Saccharomyces cerevisiae/enzimologia , Especificidade da Espécie
9.
Biochemistry ; 28(20): 8108-16, 1989 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-2532539

RESUMO

An assay for UDP-Glc:glycoprotein glucosyltransferase was developed. Incubation of rat liver microsomes with UDP-[14C]Glc led to the formation of hot trichloroacetic acid insoluble material identified as protein-linked Glc1Man7-9GlcNAc2. Addition of 8 M urea-denatured thyroglobulin to the incubation mixtures stimulated up to 10-12-fold the formation of the same compounds but only in the presence of detergents. Native thyroglobulin was ineffective. Several experiments indicated that the stimulation was due to the transfer of glucose residues from UDP-Glc to high-mannose oligosaccharides in urea-denatured thyroglobulin and that this transfer reaction did not involve dolichol mono- or diphosphate derivatives as intermediates. The glycoprotein glucosylating activity was mainly located in the endoplasmic reticulum and could glucosylate glycopeptides derived from the digestion of thyroglobulin with an unspecific protease. Glucosylation of oligosaccharides in those glycopeptides occurred, however, at a rate at least 2 orders of magnitude slower than that of the same compounds in urea-denatured thyroglobulin. Tryptic digestion of urea-denatured thyroglobulin did not affect its glucosylation rate. The structure of Glc1Man9GlcNAc2 linked to urea-denatured thyroglobulin was identical with that of Glc1Man9GlcNAc2-P-P-dolichol. The assay of UDP-Glc:glycoprotein glucosyltransferase allowed detection of the activity in microsomal membranes in which endogenous acceptors appeared to be absent or almost absent, such as those derived from mung bean, Mucor rouxii, Crithidia fasciculata, and Trypanosoma cruzi cells.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Glicoproteínas/metabolismo , Hexosiltransferases , Proteínas de Membrana , Microssomos/metabolismo , Plantas/metabolismo , Streptomyces griseus/metabolismo , Trypanosoma cruzi/metabolismo , Acetilglucosaminidase/metabolismo , Animais , Crithidia/metabolismo , Glucose/metabolismo , Glucosiltransferases/metabolismo , Glicosilação , Masculino , Manosil-Glicoproteína Endo-beta-N-Acetilglucosaminidase , Microssomos Hepáticos/metabolismo , Mucor/metabolismo , Peptídeo Hidrolases/metabolismo , Desnaturação Proteica , Ratos , Saccharomyces cerevisiae/metabolismo , Frações Subcelulares/metabolismo , Transferases/metabolismo
10.
J Biol Chem ; 269(48): 30701-6, 1994 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-7982990

RESUMO

The UDP-Glc:glycoprotein glucosyltransferase was purified to homogeneity from the fission yeast Schizosaccharomyces pombe. The enzyme has been recently suggested to be involved in the mechanism by which unfolded, partially folded, or misfolded glycoproteins are retained in the endoplasmic reticulum. The pure yeast glucosyltransferase formed protein-linked Glc1-Man9GlcNAc2,Glc1Man8GlcNAc2, and Glc1Man7GlcNAc2 when incubated with UDP-Glc and denatured thyroglobulin. The same compounds were formed upon glucosylation of endogenous acceptors by crude microsomes. The enzyme was a soluble microsomal protein that required Ca2+ for activity, used UDP-Glc and not TDP-Glc, ADP-Glc, or UDP-Gal as sugar donor, had an almost neutral optimum pH value, and as the glucosyl-transferase obtained from rat liver, glucosylated denatured but not native glycoproteins or glycopeptides. A similar enzymatic activity could not be detected in Saccharomyces cerevisiae microsomes and transient glucosylation of glycoproteins (addition of a single glucose unit to glucose-free oligosaccharides by the glucosyltransferase followed by its removal by glucosidase II) could not be detected in intact S. cerevisiae cells. These are the only eukaryotic cells described so far in which these processing reactions of the endoplasmic reticulum do not occur. Availability of the pure S. pombe enzyme will eventually allow testing the possible involvement of the glucosyltransferase in sensing glycoprotein tertiary structures in the endoplasmic reticulum.


Assuntos
Glucosiltransferases/análise , Glucosiltransferases/isolamento & purificação , Oligossacarídeos/biossíntese , Saccharomyces cerevisiae/enzimologia , Schizosaccharomyces/enzimologia , Sequência de Carboidratos , Cromatografia de Afinidade , Cromatografia em Gel , Cromatografia por Troca Iônica , Glucosiltransferases/metabolismo , Glicopeptídeos/metabolismo , Glicoproteínas/metabolismo , Cinética , Dados de Sequência Molecular , Oligossacarídeos/química , Oligossacarídeos/isolamento & purificação , Desnaturação Proteica , Especificidade da Espécie
11.
Eur J Biochem ; 213(2): 765-71, 1993 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-8477749

RESUMO

Addition of sialic acid residues in the human pathogen Trypanosoma cruzi glycoconjugates is mediated by a trans-sialidase and not by a CMP-sialic acid:glycoconjugate sialyltransferase. Incubation of trans-sialidase with N-[galactose-14C]acetyllactosamine and O-linked oligosaccharides, N-linked glycopeptides (both obtained from fetuin) or sialyllactose showed that the last three compounds were donors of sialic acid residues to the first one. Moreover, N- and O-linked oligosaccharides in asialofetuin and asialomucin, respectively, served as acceptors of sialic acid units. Gangliosides GM3, GD1a and GT1b but not GM2, GM1a nor GD1b donated sialic acid units to N-acetyllactos amine when incubated with trans-sialidase. This showed that only sialic acid units bound to terminal galactosyl residues were transferred. GM1a was converted to GD1a, and GD1b to GT1b when incubated with the appropriate donor. The fact that asialo-GM1a was converted to a ganglioside migrating as GD1a on thin-layer chromatography suggested that sialic acid units may be transferred to internal galactosyl residues, although once linked to those residues they can not be further transferred to other glycoconjugates. Sialic acid residues linked alpha 2,3- but not alpha 2,6- or alpha 2,8- were transferred by the trans-sialidase. Methyl beta-galactoside but not methyl alpha-galactoside served as acceptor of sialic acid units, thus suggesting that terminal alpha-linked galactosyl units in T. cruzi and mammalian glycoproteins are not sialylated by the enzyme. As the trans-sialidase employed in these experiments has been shown to be located on the external surface of the parasite and to be shed to the medium, the relatively broad specificity shown by the enzyme with respect to protein- and lipid-linked oligosaccharides strongly suggests that infection by T. cruzi might alter the sialic acid distribution in glycoproteins and glycolipids of the mammalian host.


Assuntos
Glicolipídeos/metabolismo , Glicoproteínas/metabolismo , Neuraminidase/metabolismo , Oligossacarídeos/metabolismo , Trypanosoma cruzi/enzimologia , Animais , Sequência de Carboidratos , Radioisótopos de Carbono , Humanos , Cinética , Dados de Sequência Molecular , Técnica de Diluição de Radioisótopos , Especificidade por Substrato , Trítio
12.
Cell ; 102(3): 325-34, 2000 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-10975523

RESUMO

Dendritic cells (DCs) developmentally regulate antigen uptake by controlling their endocytic capacity. Immature DCs actively internalize antigen. However, mature DCs are poorly endocytic, functioning instead to present antigens to T cells. We have found that endocytic downregulation reflects a decrease in endocytic activity controlled by Rho family GTPases, especially Cdc42. Blocking Cdc42 function by Toxin B treatment or injection of dominant-negative inhibitors of Cdc42 abrogates endocytosis in immature DCs. In mature DCs, injection of constitutively active Cdc42 or microbial delivery of a Cdc42 nucleotide exchange factor reactivates endocytosis. DCs regulate endogenous levels of Cdc42-GTP with activated Cdc42 detectable only in immature cells. We conclude that DCs developmentally regulate endocytosis at least in part by controlling levels of activated Cdc42.


Assuntos
Apresentação de Antígeno , Proteínas de Bactérias , Células Dendríticas/imunologia , Endocitose , Proteína cdc42 de Ligação ao GTP/metabolismo , Animais , Toxinas Bacterianas/farmacologia , Diferenciação Celular , Clatrina , Invaginações Revestidas da Membrana Celular , Regulação para Baixo , Ativação Enzimática , Masculino , Camundongos , Pinocitose , Salmonella typhimurium/imunologia , Proteína cdc42 de Ligação ao GTP/antagonistas & inibidores
13.
Minerva Anestesiol ; 68(1-2): 25-35, 2002.
Artigo em Italiano | MEDLINE | ID: mdl-11877558

RESUMO

BACKGROUND: Outcome of severely injured patients is sharply influenced by the level of prehospital and hospital organization. OBJECTIVE: To evaluate the impact of the re-organization of the trauma care process on the quality of care and final outcome of major trauma (ISS =/< 16) victims. SETTING: the Emergency Department (ED) of a 1600 bedded tertiary care hospital. INTERVENTION: a standardized approach to major trauma patients (MT) was implemented: Written protocols were established and trauma teams were organized. All anesthesiologists and trauma surgeons involved in trauma care were enrolled in an educational program including ATLS Courses and the Italian Resuscitation Council Prehospital Trauma Care Course. One of the targets was to assure the early orthopedic stabilization of limb and pelvis fractures. METHODS: Data of all major trauma victims admitted to the ED during 3 comparable periods of time: before (Jan-May 1998), during (Jan-May 1999) and after (Jan-May 2000) the implementation of the process, were retrospectively and prospectively collected and analyzed. RESULTS: MT patients admitted to the hospital increased from 39 in 1998 to 106 in 2000. For similar ISS (30.2 +/- 11.3 in 1998, 29.6 +/- 13.7 in 1999 and 30.5 +/- 12.9 in 2000) hospital mortality dropped from 42% in 1998 to 20.8%. The mean time from hospital admission to surgical orthopedic stabilization was 12 days in 1998, 4.6 in 1999 and 1.3 in 2000. In 2000, 86% of the patients with limbs fractures who required surgical stabilization, were treated within 36 hours from admission vs 11% in 1998. CONCLUSIONS: The implementation of written protocols for trauma care, the organization of trauma teams, educational programs including ATLS and PTC-IRC Courses and a strategy of early stabilization of limb fractures are associated with a dramatic decrease in hospital mortality for major trauma.


Assuntos
Serviços Médicos de Emergência/organização & administração , Mortalidade Hospitalar , Ferimentos e Lesões/mortalidade , Ferimentos e Lesões/terapia , Humanos , Itália , Procedimentos Ortopédicos , Estudos Retrospectivos , Resultado do Tratamento
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