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1.
J Dairy Sci ; 104(3): 3364-3385, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33358798

RESUMEN

The general objective of this study was to evaluate the effect of 3 intramammary antibiotic interventions using 2 commercially available antibiotics with narrow- or broad-spectrum activity on cure rates of clinical mastitis (CM) caused by gram-positive bacteria. We also compared the efficacy of treatment protocols, including a negative control, on outcomes at the cow and mammary quarter level. Before the onset of the study, 5,987 animals more than 12 mo old were randomly preassigned to 1 of 4 protocols in the event of gram-positive CM (except for Staphylococcus aureus and Trueperella pyogenes) during lactation: 3 infusions with 62.5 mg of amoxicillin performed 12 h apart (AMOX-L); 5 infusions once a day with 62.5 mg of amoxicillin (AMOX-EL); 5 infusions once a day with 125 mg of ceftiofur hydrochloride (CEFT-L); or negative control, no treatment performed until 5 d after diagnosis (NEG-CTR). Randomization was performed to preassign 90% of cows to one of the antibiotic protocols (30% in each group) and 10% to the negative control. A total of 696 quarter cases of CM met the inclusion criteria and were evaluated in the study. Quarter-level outcomes were assessed based on 5 milk samples collected up to 14 ± 3 d following enrollment (i.e., first day of treatment), whereas variables at the cow level [composite somatic cell count (SCC), milk production, and survival in the herd] were assessed up to 90 d after CM diagnosis. Streptococcus uberis, followed by Streptococcus dysgalactiae, were the main causes of gram-positive CM. Overall, clinical cure was higher for CEFT-L than for AMOX-EL, and no difference was observed between CEFT-L and AMOX-L. Likewise, no significant differences were detected on overall bacteriological cure, although some treatment effects were observed at the species level. Compared with antibiotic-treated groups, quarters assigned to NEG-CTR had higher counts of colony-forming units (cfu), 16S rRNA gene copy numbers, and Streptococcus relative abundance (RA) until d 5 after enrollment. Quarters treated with AMOX-L had higher cfu counts on d 5, 8, and 14 after enrollment compared with the other antibiotic protocols. In addition, the RA of Streptococcus spp. was higher on d 14 after enrollment for AMOX-treated quarters compared with the CEFT-L group. Linear score of SCC was higher for AMOX-treated cows than for CEFT-L in the first test day after CM. However, cows assigned to AMOX-L had higher milk production than those submitted to the AMOX-EL and CEFT-L protocols. In conclusion, the 2-d protocol with 3 intramammary infusions of amoxicillin (narrow-spectrum antimicrobial) had similar overall clinical and bacteriological cures as 5 administrations (once a day) with ceftiofur hydrochloride (wide spectrum). No significant difference was observed on CM recurrence and cow survival. However, quarters treated with 5-d protocols were more effective at reducing milk cfu counts than quarters in the AMOX-L protocol. In addition, lower Streptococcus spp. RA was observed in ceftiofur-treated quarters compared with the amoxicillin protocols at d 14 after CM diagnosis. Based on results of microbiome and bacterial load (quantitative PCR and cfu count) up to 5 d after CM diagnosis, antibiotic use remains an indispensable strategy for treatment of CM caused by gram-positive bacteria.


Asunto(s)
Enfermedades de los Bovinos , Mastitis Bovina , Mastitis , Animales , Antibacterianos/uso terapéutico , Bovinos , Enfermedades de los Bovinos/tratamiento farmacológico , Recuento de Células/veterinaria , Femenino , Lactancia , Glándulas Mamarias Animales , Mastitis/tratamiento farmacológico , Mastitis/veterinaria , Mastitis Bovina/tratamiento farmacológico , Leche , ARN Ribosómico 16S , Streptococcus
2.
Plant Dis ; 98(2): 285, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30708755

RESUMEN

In November 2012, plants of Russell prairie gentian (Eustoma grandiflorum, Lisianthus russellianus) were collected from a commercial greenhouse in Atibaia, SP, Brazil, displaying necrotic spots on leaves and necrosis on stems, followed by generalized systemic necrosis. Disease symptom incidence was estimated at 10%. Preliminary electron microscopy observations of negatively stained leaf extracts prepared from those lesions revealed the presence of a large number of spherical tospovirus-like, approximately 100 nm in diameter. Samples of infected leaves were ground in 0.01 M phosphate buffer containing 0.5% sodium sulphide and mechanically inoculated in six plants of each species of Nicotiana glutinosa, N. tabacum cv. White Burley, N. megalosiphon, N. debneyii, Datura stramonium, Chenopodium amaranticolor, C. quinoa, and E. grandiflorum. All inoculated plants displayed local lesions 4 to 5 days after inoculation, while N. debneyii and D. stramonium showed systemic symptoms, typical of Tospovirus infection. In addition, E. grandiflorum reproduced the original symptoms. Total RNA was extracted from infected E. grandiflorum and D. stramonium, and reverse transcription (RT)-PCR was performed using universal primers BR60 and BR65 (2) targeting conserved regions of the nucleocapsid gene (N). The amplification products of approximately 450 bp were purified, cloned, and sequenced. The unknown virus was identified as Chrysanthemum stem necrosis virus (CSNV-Lis) based on host range and nucleotide sequence (Genbank Accession No. KC894721) and showed 99% identity with a CSNV chrysanthemum isolate from Japan (AB600872). Maximum likelihood phylogenetic analysis using nine homologous CSNV sequences available in GenBank classified CSNV-Lis into a monophyletic group formed by chrysanthemum isolates from Japan and China while a Japanese lisianthus isolate was separately clustered. CSNV is a member of the genus Tospovirus (Bunyaviridae) and was first reported on chrysanthemum in Brazil (1) and later in the Netherlands, Slovenia, United Kingdom, and Japan (3). Despite scattered recent reports of CSNV, the simultaneous production of chrysanthemum and lisianthus crops along the year by Brazilian farmers has contributed to the virus maintenance in the field. The high identity between Brazilian and Japanese isolates of CSNV suggest a possible reintroduction of the virus through exchange of vegetative propagating material. References: (1) L. M. L. Duarte et al. J. Phytopathol. 143:569, 1995. (2) M. Eiras et al. Fitopatol. Bras. 26:170, 2001. (3) K. Momonoi et al. J. Gen. Plant Pathol. 77:142, 2011.

3.
Plant Dis ; 97(11): 1517, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30708485

RESUMEN

Zamioculcas zamiifolia (Lodd.) Engl. ("Zanzibar Gem," "ZZ plant") is the monotypic species of the genus belonging to the family Araceae. It is a stemless perennial plant native to Africa, from Kenya to South Africa, that produces succulent rhizomes at the base of its attractive dark green and glossy foliage. Symptoms of mosaic and foliar distortion were observed on a plant purchased at an ornamental plants shop in São Paulo state, Brazil. In order to identify the causal agent, transmission and serological tests, as well as electron microscopy (EM) observations, reverse transcription (RT)-PCR, and sequencing were carried out. EM observations revealed the presence of elongated, flexuous viral particles in foliar extracts and cytoplasmic lamellar aggregates of type II lamellar inclusions (Edwardson's classification), in thin sections. No symptoms were induced following mechanical inoculation on Chenopodium amaranticolor, C. murale, Gomphrena globosa, Nicotiana megalosiphon, N. debneyii, nor on the aroids Philodendron scandens, P. selloum, Dieffenbachia amoena, Colocasia esculenta, and Z. zamiifolia. Up to 2 months after inoculation, plants were still symptomless, and the virus was not detected by RT-PCR. The indirect ELISA tests were negative with antisera against Dasheen mosaic virus (gift from F. W. Zettler, University of Florida) and Turnip mosaic virus (gift from P. Roggero, IFA, Turin, Italy). RT-PCR performed on the original purchased ornamental plant with potyvirus-specific primers (CI-R = ACICCRTTYTCDATDATRTTIGTIGC and CI-F = GGIVVIGTIGGIWSIGGIAARTCIAC) targeting the cytoplasmic inclusion protein cistron of the potyvirus genome produced a fragment of approximately 650 bp (GenBank Accession No. KC990386). The sequence was similar to those of potyvirus species with nucleotide identity, determined by PAUP v.4.0b10 for Macintosh, ranging from 64% for Pokeweed mosaic virus (JQ609065) to 93% for Konjac mosaic virus KoMV-F (NC007913). KoMV has been detected in aroid species in Taiwan, India, Korea, Japan (1,2), Germany, and The Netherlands (3,4). This is the first report of a viral disease on Z. zamiifolia and of KoMV in the Americas. Such information along with the vegetative propagation of ZZ plants strongly suggests that KoMV is spread worldwide. References: (1) P. Manikonda et al. J. Phytopathol. 159:133, 2011. (2) M. Nishiguchi et al. Arch Virol. 151:1643, 2006. (3) D.-E. Lesemann and S. Winter. Acta Hort. 568:135, 2002. (4) K. Pham et al. Acta Hort. 568:143, 2002.

4.
Plant Dis ; 84(7): 739-742, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30832101

RESUMEN

Petunia plants from a nursery in the State of Rio Grande do Sul, Brazil, showed pronounced vein banding and contained isometric particles with diameters of approximately 45 and 30 nm. The larger ones apparently represent a caulimovirus, while the smaller ones, which included both empty shells and full particles, were identified as those of a new tymovirus for which we propose the name Petunia vein banding virus (PetVBV). Originally, PetVBV was transmitted only with difficulty to healthy petunia plants. However, from an experimentally infected petu-nia, it was later readily transmitted also to Nicotiana benthamiana and Nicandra physalodes, but not to other species in the Solanaceae or other plant families. It produces cytopathic effects typical for tymovirus infections. Its coat protein shows approximately 65% amino acid sequence identity with those of Eggplant mosaic and Andean potato latent viruses, to which it is also serologically more closely related than to any other tymoviruses.

5.
Plant Dis ; 84(6): 707, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30841123

RESUMEN

Tobamoviruses were detected in two ornamental plants, Dieffenbachia picta (Araceae) and Impatiens hawkeri (Balsaminaceae), from different counties in São Paulo State, Brazil. Symptoms were chlorotic spots and rings in D. picta and mosaic, blistering, and leaf deformation in I. hawkeri. Mechanical transmission from both species induced different kinds and intensities of symptoms in the same experimental hosts (Balsaminaceae, Chenopodiaceae, and Solanaceae), except Gomphrena globosa, which was infected only by the isolate from D. picta. The viruses did not infect Cucurbitaceae and Fabaceae. Indirect enzyme-linked immunosorbent assay performed with extracts from infected Nicotiana tabacum 'White Burley' and antisera against Cucumber green mottle, mosaic, Frangipani mosaic, Odontoglossum ringspot, Ribgrass mosaic, Tobacco mosaic (TMV), Tomato mosaic, Turnip vein clearing, and Youcai mosaic viruses (genus To-bamovirus) was positive only for TMV. Furthermore, the viruses isolated from D. picta and I. hawkeri cross-reacted with their heterologous antisera. Two sense primers for regions ≍200 and 90 nt upstream of the start codon and an antisense primer ≍60 nt downstream of the terminal codon of the coat protein (CP) gene were designed for two amplification assays. Migrating fragments the same size as the reverse-transcription polymerase chain reaction products from the TMV type strain (479 and 800 bp with internal and external primers, respectively) were produced. The CP gene sequence will allow comparison and identification of the two viruses isolated from D. picta and I. hawkeri.

6.
Psychol Rep ; 85(1): 145-61, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10575980

RESUMEN

The construct of self-silencing was proposed to account for women's greater vulnerability to developing depression. This study of 1,117 students (795 women and 322 men) explored possible explanations for the empirical finding that men self-silence to the same or greater extent than women. Analysis showed that men reported more self-silencing than women. A factor analysis confirmed the subscale structure of the Silencing the Self Scale for women and men, with relatively few departures from the originally proposed subscales. Depression and self-silencing scores were correlated positively for both men and women. The results of two multiple regressions, performed separately for men and women, showed that depressive symptomatology accounted for a significant percentage of the variance in self-silencing but that social desirability did not account for a significant increment in the variance accounted for in silencing the self. The scores on the Care as Self-sacrifice and the Divided Self subscales were intercorrelated for women, but not for men, indicating that there may be a sex difference in perception of self-silencing behavior.


Asunto(s)
Actitud Frente a la Salud , Trastorno Depresivo Mayor/diagnóstico , Trastorno Depresivo Mayor/psicología , Autoimagen , Adolescente , Adulto , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Caracteres Sexuales , Encuestas y Cuestionarios
7.
J Matern Fetal Med ; 6(6): 320-3, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9438213

RESUMEN

The purpose of this study was to evaluate the feasibility of an obstetrician-based cord blood collection system for the purpose of banking cord blood for unrelated donor hematopoietic stem cell transplantation. Over 200 delivering physicians and 40 area obstetrical units were educated and became involved in the collection of cord blood during the third stage of labor. These products compared favorable with those obtained after placental delivery. Issues involved in the development of quality assurance for unrelated donor banking are discussed. An obstetrician-based cord blood collection network is feasible and advantageous in that cord blood can be collected from a wider variety of communities, thus enhancing the ethnic diversity of a bank.


Asunto(s)
Bancos de Sangre , Donantes de Sangre , Recolección de Muestras de Sangre , Sangre Fetal , Trasplante de Células Madre Hematopoyéticas , Obstetricia , Bacterias/aislamiento & purificación , Estudios de Factibilidad , Femenino , Sangre Fetal/microbiología , Células Madre Hematopoyéticas , Humanos , Tercer Periodo del Trabajo de Parto , Embarazo , Control de Calidad
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