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1.
Am J Transplant ; 18(9): 2148-2162, 2018 09.
Article in English | MEDLINE | ID: mdl-29673058

ABSTRACT

Sensitization is common in pediatric heart transplant candidates and waitlist mortality is high. Transplantation across a positive crossmatch may reduce wait time, but is considered high risk. We prospectively recruited consecutive candidates at eight North American centers. At transplantation, subjects were categorized as nonsensitized or sensitized (presence of ≥1 HLA antibody with MFI ≥1000 using single antigen beads). Sensitized subjects were further classified as complement-dependent cytotoxicity crossmatch (CDC-crossmatch) positive or negative and as donor-specific antibodies (DSA) positive or negative. Immunosuppression was standardized. CDC-crossmatch-positive subjects also received perioperative antibody removal, maintenance corticosteroids, and intravenous immunoglobulin. The primary endpoint was the 1 year incidence rate of a composite of death, retransplantation, or rejection with hemodynamic compromise. 317 subjects were screened, 290 enrolled and 240 transplanted (51 with pretransplant DSA, 11 with positive CDC-crossmatch). The incidence rates of the primary endpoint did not differ statistically between groups; nonsensitized 6.7% (CI: 2.7%, 13.3%), sensitized crossmatch positive 18.2% (CI: 2.3%, 51.8%), sensitized crossmatch negative 10.7% (CI: 5.7%, 18.0%), P = .2354. The primary endpoint also did not differ by DSA status. Freedom from antibody-mediated and cellular rejection was lower in the crossmatch positive group and/or in the presence of DSA. Follow-up will determine if acceptable outcomes can be achieved long-term.


Subject(s)
Blood Grouping and Crossmatching/mortality , Graft Rejection/mortality , HLA Antigens/immunology , Heart Transplantation/adverse effects , Isoantibodies/immunology , Postoperative Complications , Tissue Donors , Adolescent , Child , Child, Preschool , Female , Follow-Up Studies , Graft Rejection/etiology , Graft Survival , Histocompatibility Testing , Humans , Immunosuppression Therapy , Infant , Isoantibodies/blood , Male , Prognosis , Prospective Studies , Risk Factors , Survival Rate
2.
Am J Transplant ; 18(9): 2163-2174, 2018 09.
Article in English | MEDLINE | ID: mdl-29442424

ABSTRACT

Data on the clinical importance of newly detected donor-specific anti-HLA antibodies (ndDSAs) after pediatric heart transplantation are lacking despite mounting evidence of the detrimental effect of de novo DSAs in solid organ transplantation. We prospectively tested 237 pediatric heart transplant recipients for ndDSAs in the first year posttransplantation to determine their incidence, pattern, and clinical impact. One-third of patients developed ndDSAs; when present, these were mostly detected within the first 6 weeks after transplantation, suggesting that memory responses may predominate over true de novo DSA production in this population. In the absence of preexisting DSAs, patients with ndDSAs had significantly more acute cellular rejection but not antibody-mediated rejection, and there was no impact on graft and patient survival in the first year posttransplantation. Risk factors for ndDSAs included common sensitizing events. Given the early detection of the antibody response, memory responses may be more important in the first year after pediatric heart transplantation and patients with a history of a sensitizing event may be at risk even with a negative pretransplantation antibody screen. The impact on late graft and patient outcomes of first-year ndDSAs is being assessed in an extended cohort of patients.


Subject(s)
Graft Rejection/mortality , Graft Survival/immunology , HLA Antigens/immunology , Heart Transplantation/adverse effects , Isoantibodies/adverse effects , Postoperative Complications , Tissue Donors , Adolescent , Adult , Child , Child, Preschool , Female , Follow-Up Studies , Graft Rejection/etiology , Histocompatibility Testing , Humans , Incidence , Infant , Isoantibodies/blood , Isoantibodies/immunology , Male , Prognosis , Prospective Studies , Risk Factors , Survival Rate , Young Adult
3.
Genet Mol Res ; 13(4): 9390-402, 2014 Nov 11.
Article in English | MEDLINE | ID: mdl-25501150

ABSTRACT

The occurrence of Fusarium spp associated with pecan tree (Carya illinoinensis) diseases in Brazil has been observed in recent laboratory analyses in Rio Grande do Sul State. Thus, in this study, we i) obtained Fusarium isolates from plants with disease symptoms; ii) tested the pathogenicity of these Fusarium isolates to pecan; iii) characterized and grouped Fusarium isolates that were pathogenic to the pecan tree based on morphological characteristics; iv) identified Fusarium spp to the species complex level through TEF-1α sequencing; and v) compared the identification methods used in the study. Fifteen isolates collected from the inflorescences, roots, and seeds of symptomatic plants (leaf necrosis or root rot) were used for pathogenicity tests. Morphological characterization was conducted using only pathogenic isolates, for a total of 11 isolates, based on the mycelial growth rate, sporulation, colony pigmentation, and conidial length and width variables. Pathogenic isolates were grouped based on morphological characteristics, and molecular characterization was performed by sequencing TEF-1α genes. Pathogenic isolates belonging to the Fusarium chlamydosporum species complex, Fusarium graminearum species complex, Fusarium proliferatum, and Fusarium oxysporum were identified based on the TEF-1α region. Morphological characteristics were used to effectively differentiate isolates and group the isolates according to genetic similarity, particularly conidial width, which emerged as a key morphological descriptor in this study.


Subject(s)
Carya/microbiology , Fusarium/cytology , Fusarium/genetics , Plant Diseases/microbiology , Trees/microbiology , Brazil , Colony Count, Microbial , Fusarium/isolation & purification , Fusarium/pathogenicity , Phylogeny , Spores, Fungal/growth & development
4.
Plant Dis ; 98(6): 847, 2014 Jun.
Article in English | MEDLINE | ID: mdl-30708668

ABSTRACT

Pecan [Carya illinoinensis (Wangenh.) K. Koch] is an important producing nut tree that has been intensively cultivated in the state of Rio Grande do Sul (Brazil) in recent decades. This species is commonly grown in association with other crops and more often with cattle or sheep. An elevated incidence of the fungal genus Fusarium was observed during a quality control seed assay of pecan seeds obtained from orchards in the city of Anta Gorda (28°53'54.7″ S, 52°01'59.9″ W). Concomitantly, seedlings of this species, cultivated in a nursery, showed foliar necrosis, wilt, and root rot. The fungus was thereafter isolated from the seeds (from original seeds lots) and subcultured from single spores. Cultures were purified in order to perform pathogenicity tests. The isolated Fusarium sp. was increased on autoclaved wet corn kernels that were incubated for 14 days (1), and then were mixed with commercial substrate (sphagnum turf, expanded vermiculite, dolomitic limestone, gypsum, and NPK fertilizer) in plastic trays (capacity 7 L), with drainage holes. Twenty seeds were sowed and 90 days later, evaluations were undertaken. Forty percent of the seedlings presented symptoms, i.e., foliar necrosis and wilt owing to root rot. Fusarium sp. was re-isolated from the affected roots by transferring hyphal tips to potato dextrose agar (PDA) and carnation leaf agar (CLA) medium in petri dishes in order to identify the species morphologically. On PDA, the colony pigmentation was yellowish brown and the aerial mycelium was whitish to peach; macroconidia were relatively long and narrow (31.75 × 4.02 µm), with 5 septa on average, and whip-like bent apical cells (2). Chlamydospores were not observed on PDA or CLA. Primer pairs ITS1 and ITS4 (3) and EF1-T and EF1-1567R (4) were employed to amplify the internal transcribed spacer (ITS) and elongation factor-1α (TEF 1-α) regions, respectively. The resulting DNA sequences showed 99% for ITS and 98% for TEF 1-α similarity with Fusarium equiseti (Corda) Sacc. and phylogenetic analysis grouped it with sequences of this species. The consensus sequence was submitted to GenBank and received the accession numbers KC810063 (ITS) and KF601580 (TEF 1-α). The pathogen was re-isolated on PDA and CLA substrate in order to complete Koch's postulates. The pathogenicity test was repeated with the same conditions described before and the results were confirmed. No symptoms were observed on the control seedlings. This species is considered a weak parasite (2); however, it has been reported causing wilt in Coffea arabica in Brazil (5). This pathogen could cause serious damage and high losses to seedling in commercial nurseries. Besides that, it could also carry the disease to the field causing further damage on established plants. To our knowledge, this is the first to report of F. equiseti causing foliar necrosis and wilt on C. illinoinensis in Brazil. References: (1) L. H. Klingelfuss et al. Fitopatol. Brasil. 32:1, 2007. (2) W. Gerlach and H. Nirenberg. The Genus Fusarium - a Pictorial Atlas. Biologische Bundesanstalt für Land- und Forstwirtschaft, Braunschweig, Germany, 1982. (3) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications, Academic Press, San Diego, CA, 1990. (4) S. A. Rehner and E. A. Buckley. Mycologia 97:84, 2005. (5) L. H. Pfenning and M. F. Martins. Page 283 in: Simpósio de Pesquisa dos Cafés do Brasil, 2000.

5.
Plant Dis ; 98(1): 156, 2014 Jan.
Article in English | MEDLINE | ID: mdl-30708578

ABSTRACT

Cultivated grapevine (Vitis labrusca and V. vinifera) is of considerable economic importance to the Brazilian fruit industry for both fresh market consumption and for the production of wines, sparkling beverages, and juices. Black foot disease is caused by fungi of the genera Ilyonectria P. Chaverri & C. Salgado (anamorph: Cylindrocarpon Wollew.), Campylocarpon Halleen, Schroers & Crous, and Cylindrocladiella Boesew. In 2012, 4- to 40-year-old grapevines (Vitis spp.) showing reduced vigor, vascular lesions, necrotic root lesions, delayed budding, vine decline, and death were collected from seven locations at Rio Grande do Sul state, Brazil. Fungal isolations were made from root fragments and crown lesions (at least 2 cm above the bottom) on potato dextrose agar (PDA) medium added with 0.5 g L-1 streptomycin sulfate. Eight isolates were obtained and identified on the basis of morphological features and multi-gene analysis (rDNA-ITS, ß-tubulin, and histone H3) as Ilyonectria macrodidyma (Halleen, Schroers & Crous) P. Chaverri & C. Salgado. One representative isolate (Cy5UFSM) was used for more detailed morphological and molecular characterization, and pathogenicity confirmation. When incubated in the dark at 20°C for 7 to 10 days, colonies of felty straw-colored mycelium (3) 4.79 cm diameter on average were observed. No sporodochia or other fruiting bodies were produced on carnation leaf agar (CLA) medium after 30 days. Microconidia that were produced after 5 weeks on spezieller nährstoffarmer agar (SNA) medium with addition of two pieces of 1 cm2 filter paper showed ovoid and ellipsoid shape (6.4 × 3.6 µm) and one-septate macroconidia (17.3 × 4.1 µm). To confirm the species, primer pairs ITS1 and ITS4 (4); Bt2a and Bt2b; and H3-1a and H3-1b (2) were used to amplify the ITS1-5.8S rRNA-ITS2, part of the ß-tubulin and histone H3 genes, respectively. Sequences of these three regions showed 99, 100, and 100% of homology with I. macrodidyma, respectively. To confirm pathogenicity, 4-month-old rooted cuttings of V. labrusca cv. Bordô were inoculated by immersing them in a conidial suspension of the isolate (106 conidia ml-1) for 60 min (1). Thirty days later, inoculation was performed again by drenching the crown with 40 ml of 106 conidia ml-1 suspension to ensure infection of the roots. In the control treatment, plants were inoculated with sterile distilled water. Plants inoculated with I. macrodidyma showed necrosis of the leaf ribs, reduction in root mass, root and crown necrosis, browning of vessels, drying of shoots, and death. I. macrodidyma was re-isolated from the crown necrosis and vascular lesions, confirming Koch's postulates. To our knowledge, this is the first report of I. macrodidyma associated with black foot disease of grapevine in Brazil, which poses considerable threat to the industry unless management options are realized. References: (1) A. Cabral et al. Phytopathol. Mediterr. 51:340, 2012. (2) N. L. Glass et al. Appl. Environ. Microbiol. 61:1323, 1995. (3) R. W. Rayner. A Mycological Colour Chart. Commonwealth Mycological Institute and British Mycological Society, 1970. (4) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, CA, 1990.

6.
Plant Dis ; 98(6): 845, 2014 Jun.
Article in English | MEDLINE | ID: mdl-30708651

ABSTRACT

In August 2012, symptoms of black foot disease were observed on 21-year-old grapevines (Vitis labrusca cv. Bordô; own-rooted cultivar) at Nova Pádua city, Rio Grande do Sul state, Brazil. Symptomatic plants showed reduced vigor, vascular lesions, decline and death of vines, and necrotic lesions on roots. Isolation of fungi associated with necrotic root tissue was made on potato dextrose agar (PDA) medium containing 0.5 g L-1 streptomycin sulfate. Cultures were incubated at 25°C for 7 days in darkness, and single-spore cultures were obtained from the colonies emerging from the diseased tissue. For morphological characterization, cultures were transferred to PDA and spezieller nährstoffarmer agar (SNA) medium with addition of two pieces of 1 cm2 filter paper. One representative isolate (Cy9UFSM) was used for morphological and molecular characterization and pathogenicity confirmation. After 10 days growth on PDA at 20°C in the dark, colonies were umber to chestnut in color (3), appeared cottony to felty in texture, and sporulated profusely. After 5 weeks on SNA and under dark conditions at 20°C, cultures formed macroconidia predominantly on simple conidiophores, 1 to 3 septate, with both ends slightly rounded. Macroconidia varied in size depending on the number of cells as follows: one-septate (23-) 27.7 (-31) × (4.5-) 5.8 (-7) µm; two-septate (26-) 30.1 (-34) × (5-) 5.6 (-6) µm; and three-septate (24-) 31.2 (-35) × (5-) 5.8 (-6.5) µm. Microconidia were observed and did not have a visible hilum (6-) 11.2 (-17) × (3.5-) 4.2 (-5) µm (n = 30 observations per structure). Brown, thick-walled globose to subglobose chlamydospores were produced abundantly on PDA, (8.5-) 13.8 (-17) µm. To confirm the species, primer pairs H3-1a and H3-1b (2) were used to amplify a portion the histone H3 gene. Sequence of this region showed 98% similarity with a reference sequence for Ilyonectria robusta (A.A. Hildebr.) A. Cabral & Crous (GenBank Accession No. JF735530). Thus, both morphological and molecular criteria supported identification of the strain as I. robusta. This isolate was deposited in GenBank as accession KF633172. To confirm pathogenicity, 4-month-old rooted cuttings of Vitis labrusca cv. Bordô were inoculated by immersing roots in a conidial suspension (106 ml-1) for 60 min. After inoculation, the cuttings were planted in 1-L bags containing commercial substrate (MecPlant). Thirty days later, each plant was re-inoculated by applying 40 ml of a conidial suspension (106 ml-1) to the commercial substrate. Ten single-vine replicates were used for each isolate, and 10 water-inoculated vines were included as controls. After 4 months, the inoculated plants showed a 22.5% reduction of root mass, with root and crown necrosis, browning of vessels, and 20% mortality. Control plants treated with water remained symptomless. The fungus was re-isolated from blackened tissue of wood from the basal end of rooted cuttings, thereby satisfying Koch's postulates. I. robusta was first associated with black foot disease of grapevine in Portugal in 2012 (1). To our knowledge, this is the first report in southern Brazil of I. robusta associated with black foot disease of grapevine. References: (1) A. Cabral et al. Mycol. Prog. 11:655, 2012. (2) N. L. Glass et al. Appl. Environ. Microbiol. 61:1323, 1995. (3) R. W. Rayner. A mycological colour chart. Commonwealth Mycological Institute and British Mycological Society, 1970.

7.
Plant Dis ; 98(4): 567, 2014 Apr.
Article in English | MEDLINE | ID: mdl-30708698

ABSTRACT

Since 1999, the decline of American grapevines (Vitis labrusca L.) has been common in Rio Grande do Sul, Brazil (1). In August 2012, V. labrusca with black foot symptoms were collected in vineyards in the Serra Gaúcha Region. Symptomatic plants had low vigor, vascular lesions, delayed budding, and decline and death of vines. Symptomatic roots had necrotic lesions and reduced biomass. Fungal isolations were made from necrotic root and crown fragments (own-rooted cultivar) on potato dextrose agar (PDA) medium amended with 0.5 g L-1 streptomycin sulfate. Putative colonies of "Cylindrocarpon" pauciseptatum Schroers & Crous were obtained from single macroconidia isolations. Two isolates were used to confirm the identity of isolated colonies: Cy12UFSM and Cy13UFSM. After incubation in the dark for 10 days at 20°C, the isolated mycelial colonies, which were cottony white to felty in texture, became dark orange to brown. Both isolates produced chlamydospores in chains at 40 days. Chlamydospores of Cy12UFSM and Cy13UFSM were 9 to 12 µm and 5 to 11.5 µm in diameter. Sporodochia formation on carnation leaf agar (CLA) medium was observed after 30 days. To encourage development of conidia, the isolates were grown on spezieller nährstoffarmer agar (SNA) medium for five weeks at 20°C with addition of two pieces of 1 cm2 filter paper. Microconidia of Cy12UFSM were 4 to 8.5 × 3.5 to 5 µm and those of Cy13UFSM were 3.5 to 7.5 × 3 to 5 µm. Macroconida were predominantly 3-septate (Cy12UFSM was 36 to 45 × 7.5 to 9 µm and Cy13UFSM was 30 to 38 × 7.5 to 8 µm), but 1-, 2- septate macroconidia were observed. The sizes of the three spore types and colony morphology for our isolates were similar to those described by Schroers et al. (3) for "C." pauciseptatum. To further confirm the identity of Cy12UFSM and Cy13UFSM, multi-gene DNA sequence analysis (rDNA-ITS, ß-tubulin, and histone H3) was conducted using primer pairs ITS1 and ITS4 (4), Bt2a and Bt2b, and H3-1a and H3-1b (2), which amplify the ITS1-5.8S rRNA-ITS2 genes, part of the ß-tubulin gene, and the histone H3 gene, respectively. Sequences of these three regions had 99, 99, and 97% similarity with references sequences of "C." pauciseptatum (isolate Cy238; accessions ITS [JF735307]; ß-tubulin [JF735435], and histone H3 [JF735582], respectively). To evaluate pathogenicity, 4-month-old rooted cuttings of V. labrusca cv. Bordô were inoculated with two isolates by immersing them in a conidial suspension (106 conidia ml-1) for 60 min. Ten single-vine replicates were used for each isolate, and 10 water-inoculated vines were included as controls. Thirty days after inoculation, vines were re-inoculated with 40 ml of a 106 conidia ml-1 suspension to ensure root infection. After 4 months, the inoculated plants had reduced root mass relative to controls (39.18% for Cy12UFSM and 18.27% for Cy13UFSM). Inoculated plants also had root and crown necrosis, vascular lesions, shoot decline, and vine mortality (60 and 80% mortality for Cy12UFSM and Cy13UFSM, respectively). All water-inoculated control plants remained symptomless. The fungi Cy12UFSM and Cy13UFSM were re-isolated from infected woody tissues, confirming Koch's postulates. To our knowledge, this is the first report of "C." pauciseptatum associated with black foot disease of grapevine in Brazil, which may potentially impact the sustainability of grapevine nurseries and vineyard productivity. References: (1) L. R. Garrido et al. Fitopatol. Brasil. 29:548, 2004. (2) N. L. Glass et al. Appl. Environ. Microbiol. 61:1323, 1995. (3) H. J. Schoers et al. Mycol. Res. 112:82, 2008. (4) T. J. White et al. Amplification Pages 315-322 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, CA, 1990.

8.
Plant Dis ; 97(7): 995, 2013 Jul.
Article in English | MEDLINE | ID: mdl-30722564

ABSTRACT

An elevated incidence of the fungal genus Fusarium was ascertained during a health quality analysis of a batch of Pinus elliottii Englm. seeds obtained from the Florestas Institute for Agricultural and Forest Research (Fundação Estadual de Pesquisa Agropecuária [FEPAGRO] Florestas) in Santa Maria (29° 39' 55″ S and 53° 54' 45″ W), state of Rio Grande do Sul, Brazil. This genus comprised about 75% of all fungal genera observed in a blotter test. The fungus was then isolated and purified to perform pathogenicity tests. Healthy seeds of P. elliottii were inoculated by contact with fungal mycelium for 48 h (3). Forty-two days after inoculation, a reduction was observed in the germination potential of the seeds; however, those seeds that germinated developed normally until, as seedlings, they suffered damping-off. Fusarium was isolated from the affected vegetal material by transferring mycelium tips to potato dextrose agar (PDA) medium in petri dishes in order to morphologically identify the species. After 72 h, a tan mycelial pad 5.5 cm in diameter had formed. After transfer to carnation leaf agar (CLA), pale orange sporodochia that formed macroconidia could be observed. The macronidia were relatively short and narrow (40.2 × 4.7 µm), each containing a mean of 5 septa; the apical cell was pointed, while the basal one was foot-shaped (2,4). The chlamydospores formed in clusters, while the conidiogenous cells could be seen on top of monophialides. Primer pairs ITS1 and ITS4, EF1-T and EF1-567R, and ßtub-F and ßtub were employed to amplify the three regions ITS1.8S ITS2, elongation factor - 1α (TEF 1-α), and ß-tubulin, respectively. The sequences of these three regions showed 97, 95, and 99% of similarity with Fusarium sambucinum Fückel, respectively. The pathogen was reinoculated on P. elliottii seeds in order to complete Koch's postulates. The pathogenicity test was repeated with the same conditions described before and the results were confirmed. No occurrence of damping-off was observed in the control seedlings. The inoculated seedlings showed, besides damping-off, a visible reduction in root system expansion as well as reductions in fresh and dry tissue weight. F. sambucinum has already been reported on P. radiata D. Don in New Zealand, causing root rot and dieback (1); however, in Brazil, the present study is, to the best of our knowledge, the first to report the association of this pathogen with P. elliottii. References: (1) M. A. Dick and K. Dobbie. N. Z. Plant Prot. 55:58, 2002. (2) W. Gerlach and H. Nirenberg. The Genus Fusarium - A Pictorial Atlas. Biologische Bundesanstalt für Land - und. Forstwirtschaft, Berlin, 1982. (3) M. Lazarotto et al. Summa Phytopathol. 36:134, 2010. (4) J. F. Leslie and B. A. Summerell. The Fusarium Laboratory Manual, 1st ed. Wiley-Blackwell, Hoboken, NJ, 2006.

9.
Plant Dis ; 96(12): 1826, 2012 Dec.
Article in English | MEDLINE | ID: mdl-30727274

ABSTRACT

Conspicuous leaf spots in combination with fruit spots were observed for the first time in April and May 2010 on a 30-ha pecan [Carya illinoensis (Wangenh.) K. Koch] orchard in the state of Rio Grande do Sul, Brazil. Initially, tiny grey spots were observed on leaves and, over time, the spots expanded to become gray to light brown circles surrounded by a dark brown border, followed by leaves falling. Eventually, fruits were also attacked, with typical symptoms beginning with tiny water soaked spots which then became necrotic. The disease was also observed in pecan nursery and field seedlings. Isolation of the pathogen from symptomatic leaves and morphological identification by conidia characters (number of cells, color, hyaline terminal cells, number of appendages) revealed Pestalotiopsis sp. (2) as the causal agent of the disease. Conidia constituted of transverse septa with four dark intermediate sections and two hyaline terminal sections. One of the terminal sections presented two or three apical appendages. Conidia averaged 6.88 µm wide × 31.00 µm long, not considering the apical appendages. Primers ITS 1 and ITS 4 were used to amplify the internal transcribes spacer ITS 1-5.8S-ITS 2 region. Nucleotide sequences were 99% similar to Pestalotiopsis clavispora (G.F. Atk.) Steyaert. Conidia produced on potato dextrose agar medium were used to inoculate 8 plants with a spore suspension of 2.0 × 106 conidia/ml. Eight additional plants were used as control (non-inoculated). The inoculation was performed by spraying the suspension onto the leaves of Pecan seedlings and the plants were incubated for 72 h in a humid chamber (1). All inoculated plants showed symptoms 25 days after inoculation and the fungus was reisolated. The pathogenicity test was repeated once. Ten more isolates collected from four different cities in the same state were identified as Pestalotiopsis spp. by morphological characterization and pathogenicity was confirmed. Because this disease causes losses on production of nuts indirectly by reducing photosynthetically active area when the pathogen attacks leaves and directly when attacking fruits, it may restrict the production where the pathogen occurs. On some orchards in the state of Rio Grande do Sul, the attack rate reached 80% of the plants. P. clavispora has been reported causing stem end-rot of avocado in Chile (3), but this note constitutes the first report, to our knowledge, of P. clavispora causing leaf spot on C. illinoensis in Brazil. References: (1) A. C. Alfenas and F. A. Ferreira. Page 117 in: Métodos em Fitopatologia. A. C Alfenas and R. G. Mafia (eds.). Editora: UFV, Viçosa, 2007. (2) S. S. N. Maharachchikumbura et al. Fungal Diversity 50:167, 2011. (3) A. L. Valencia et al. Plant Dis. 95:492, 2011.

10.
Am J Transplant ; 10(9): 2116-23, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20883546

ABSTRACT

We assessed the association of socioeconomic (SE) position with graft loss in a multicenter cohort of pediatric heart transplant (HT) recipients. We extracted six SE variables from the US Census 2000 database for the neighborhood of residence of 490 children who underwent their primary HT at participating transplant centers. A composite SE score was derived for each child and four groups (quartiles) compared for graft loss (death or retransplant). Graft loss occurred in 152 children (122 deaths, 30 retransplant). In adjusted analysis, graft loss during the first posttransplant year had a borderline association with the highest SE quartile (HR 1.94, p = 0.05) but not with race. Among 1-year survivors, both black race (HR 1.81, p = 0.02) and the lowest SE quartile (HR 1.77, p = 0.01) predicted subsequent graft loss in adjusted analysis. Among subgroups, the lowest SE quartile was associated with graft loss in white but not in black children. Thus, we found a complex relationship between SE position and graft loss in pediatric HT recipients. The finding of increased risk in the highest SE quartile children during the first year requires further confirmation. Black children and low SE position white children are at increased risk of graft loss after the first year.


Subject(s)
Black People , Heart Transplantation/ethnology , Hispanic or Latino , Social Class , White People , Adolescent , Child , Child, Preschool , Cohort Studies , Female , Graft Rejection/epidemiology , Heart Transplantation/mortality , Humans , Infant , Male , Postoperative Period , Reoperation , Residence Characteristics , Risk Assessment , Time Factors , Treatment Failure
11.
Am J Transplant ; 9(12): 2808-15, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19845580

ABSTRACT

Racial differences in outcomes are well known in children after heart transplant (HT) but not in children awaiting HT. We assessed racial and ethnic differences in wait-list mortality in children <18 years old listed for primary HT in the United States during 1999-2006 using multivariable Cox models. Of 3299 listed children, 58% were listed as white, 20% as black, 16% as Hispanic, 3% as Asian and 3% were defined as 'Other'. Mortality on the wait-list was 14%, 19%, 21%, 17% and 27% for white, black, Hispanic, Asian and Other children, respectively. Black (hazard ratio [HR] 1.6, 95% confidence interval [CI] 1.3, 1.9), Hispanic (HR 1.5, CI 1.2, 1.9), Asian (HR, 2.0, CI 1.3, 3.3) and Other children (HR 2.3, CI 1.5, 3.4) were all at higher risk of wait-list death compared to white children after controlling for age, listing status, cardiac diagnosis, hemodyamic support, renal function and blood group. After adjusting additionally for medical insurance and area household income, the risk remained higher for all minorities. We conclude that minority children listed for HT have significantly higher wait-list mortality compared to white children. Socioeconomic variables appear to explain a small fraction of this increased risk.


Subject(s)
Ethnicity , Heart Defects, Congenital/mortality , Heart Transplantation , Racial Groups , Waiting Lists , ABO Blood-Group System , Adolescent , Black or African American , Asian People , Child , Child, Preschool , Cohort Studies , Female , Heart Transplantation/mortality , Hispanic or Latino , Humans , Infant , Male , Minority Groups , Multivariate Analysis , Proportional Hazards Models , Socioeconomic Factors , United States , White People
12.
Science ; 181(4095): 156-8, 1973 Jul 13.
Article in English | MEDLINE | ID: mdl-17746623

ABSTRACT

The backscattering of alpha particles from a radioactive source can be used to determine the amounts of heavy elements such as lead in surface materials. A light, portable instrument has been constructed that can be used as a survey meter for painted surfaces. It has a sensitivity of 0.3 percent by weight in a measurement of a few minutes.

13.
Circulation ; 114(4): 273-80, 2006 Jul 25.
Article in English | MEDLINE | ID: mdl-16847155

ABSTRACT

BACKGROUND: The Fontan procedure is a successful palliation for children with single-ventricle physiology; however, many will eventually require heart transplantation. The purpose of this study was to determine risk factors for death awaiting transplantation and to examine results after transplantation in Fontan patients. METHODS AND RESULTS: A retrospective, multi-institutional review was performed of 97 Fontan patients <18 years of age listed at 17 Pediatric Heart Transplant Study centers from 1993 to 2001. Mean age at listing was 9.7 years (0.5 to 17.9 years); 25% were <4 years old; 53% were United Network for Organ Sharing status 1; 18% required ventilator support. Pretransplantation survival was 78% at 6 months and 74% at 12 months and was similar to 243 children with other congenital heart disease (CHD) and 747 children without congenital heart disease (No-CHD), who were also awaiting transplantation. Patients who were younger, status 1, had shorter interval since Fontan, or were on a ventilator were more likely to die while waiting. At 6 months, the probability of receiving a transplant was similar for status 1 and 2 (65% versus 68%); however, the probability of death was higher for status 1 (22% versus 5%). Seventy patients underwent transplantation. Survival was 76% at 1 year, 70% at 3 years, and 68% at 5 years, slightly less than CHD and No-CHD patients. Causes of death included infection (30%), graft failure (17%), rejection (13%), sudden death (13%), and graft coronary artery disease (9%). Protein-losing enteropathy (present in 34 patients) resolved in all who survived >30 days after transplantation. CONCLUSIONS: Heart transplantation is an effective therapy for pediatric patients with a failed Fontan. Although early posttransplantation survival is slightly lower than other patients with CHD, long-term results are encouraging, and protein-losing enteropathy can be expected to resolve.


Subject(s)
Fontan Procedure , Heart Diseases/surgery , Heart Transplantation , Salvage Therapy/methods , Adolescent , Cause of Death , Child , Child, Preschool , Heart Diseases/complications , Heart Diseases/congenital , Heart Diseases/mortality , Heart Transplantation/adverse effects , Heart Transplantation/mortality , Humans , Infant , Protein-Losing Enteropathies/etiology , Respiration, Artificial , Retrospective Studies , Salvage Therapy/adverse effects , Salvage Therapy/mortality , Survival Rate , Treatment Failure , Treatment Outcome
14.
J Clin Invest ; 102(6): 1161-72, 1998 Sep 15.
Article in English | MEDLINE | ID: mdl-9739050

ABSTRACT

Endothelial cells play a central role in the coordination of the inflammatory response. In mucosal tissue, such as the lung and intestine, endothelia are anatomically positioned in close proximity to epithelia, providing the potential for cell-cell crosstalk. Thus, in this study endothelial-epithelial biochemical crosstalk pathways were studied using a human intestinal crypt cell line (T84) grown in noncontact coculture with human umbilical vein endothelia. Exposure of such cocultures to endothelial-specific agonists (LPS) resulted in activation of epithelial electrogenic Cl- secretion and vectorial fluid transport. Subsequent experiments revealed that in response to diverse stimuli (LPS, IL-1alpha, TNF-alpha, hypoxia), endothelia produce and secrete a small, stable epithelial secretagogue into conditioned media supernatants. Further experiments identified this secretagogue as 6-keto-PGF1alpha, a stable hydrolysis product of prostacyclin (PGI2). Results obtained with synthetic prostanoids indicated that 6-keto-PGF1alpha (EC50 = 80 nM) and PGI2 stable analogues (EC50 = 280 nM) activate the same basolaterally polarized, Ca2+-coupled epithelial receptor. In summary, these findings reveal a previously unappreciated 6-keto-PGF1alpha receptor on intestinal epithelia, the ligation of which results in activation of electrogenic Cl- secretion. In addition, these data reveal a novel action for the prostacyclin hydrolysis product 6-keto-PGF1alpha and provide a potential endothelial- epithelial crosstalk pathway in mucosal tissue.


Subject(s)
6-Ketoprostaglandin F1 alpha/metabolism , Chlorides/metabolism , Endothelium, Vascular/physiology , Epithelial Cells/physiology , Paracrine Communication , Receptors, Prostaglandin/metabolism , 6-Ketoprostaglandin F1 alpha/analogs & derivatives , Carbachol/pharmacology , Cell Polarity , Cells, Cultured , Coculture Techniques , Culture Media, Conditioned , Cyclooxygenase 2 , Epoprostenol/analogs & derivatives , Humans , Hypoxia/metabolism , Interleukin-1/pharmacology , Isoenzymes/metabolism , Lipopolysaccharides/pharmacology , Membrane Proteins , Prostaglandin-Endoperoxide Synthases/metabolism , Prostaglandins/pharmacology , Tumor Necrosis Factor-alpha/pharmacology
15.
Circulation ; 102(17): 2094-9, 2000 Oct 24.
Article in English | MEDLINE | ID: mdl-11044426

ABSTRACT

BACKGROUND: The late clinical status of Fontan patients after fenestration closure is unknown. Data are now available on all patients who underwent closure from 1989 to 1999. METHODS AND RESULTS: All patients who underwent catheter closure of a Fontan fenestration were enrolled in either the Clamshell (1989 to 1994) or CardioSEAL (1996 to 1999) regulatory trials. Physiological values obtained at catheterization helped assess the hemodynamic effects of fenestration occlusion. In addition to survival, outcomes assessed included O(2) saturations, medication use, significant clinical findings (eg, heart failure, protein-losing enteropathy, or new arrhythmias), and somatic growth. Of 181 patients who underwent closure, 27 had additional significant leaks. The remaining 154 patients constituted the study group. Median time from closure to latest follow-up was 3.4 years (range 0.4 to 10.3 years). Fenestration closure increased O(2) saturation 9.4% on average (P:<0. 001). The numbers of patients receiving digoxin or diuretics decreased at the most recent follow-up compared with baseline (P:<0. 001), but use of antiarrhythmic agents increased marginally (P:=0. 05). Height and weight percentiles rose (medians of 2 and 4, respectively; P:<0.001). Clinical decompensation during follow-up of 154 patients was rare (4.5%), with 2 deaths, 3 Fontan revisions, and 1 patient each with protein-losing enteropathy and ascites. No other patient developed chronic congestive symptoms; 21 patients developed new arrhythmias, and 2 had a stroke or transient ischemic attack. CONCLUSIONS: Fenestration closure in Fontan patients was followed by improved oxygenation, reduced need for anticongestive medication, and improved somatic growth at latest follow-up. Death (1.3%) or chronic decompensation (3.2%) was rare.


Subject(s)
Fontan Procedure/adverse effects , Adolescent , Adult , Arrhythmias, Cardiac/etiology , Cardiac Output , Central Venous Pressure , Child , Child, Preschool , Female , Follow-Up Studies , Fontan Procedure/methods , Heart Failure/etiology , Humans , Infant , Male , Oxygen/metabolism , Prostheses and Implants , Time Factors , Treatment Outcome
16.
J Am Coll Cardiol ; 33(6): 1702-9, 1999 May.
Article in English | MEDLINE | ID: mdl-10334446

ABSTRACT

OBJECTIVES: The present study was undertaken to determine the independent risk factors for early mortality in the current era after arterial switch operation (ASO). BACKGROUND: Prior reports on factors affecting outcome of the ASO demonstrated that abnormal coronary arterial patterns were associated with increased risk of early mortality. As diagnostic, surgical and perioperative management techniques continue to evolve, the risk factors for the ASO may have changed. METHODS: All patients who underwent the ASO at Children's Hospital, Boston between January 1, 1992 and December 31, 1996 were included. Hospital charts, echocardiographic and cardiac catheterization data and operative reports of all patients were reviewed. Demographics and preoperative, intraoperative and postoperative variables were recorded. RESULTS: Of the 223 patients included in the study (median age at ASO = 6 days and median weight = 3.5 kg), 26 patients had aortic arch obstruction or interruption, 12 had Taussig-Bing anomaly, 12 had multiple ventricular septal defects, 8 had right ventricular hypoplasia and 6 were premature. There were 16 early deaths (7%), with 3 deaths in the 109 patients considered "low risk" (2.7%). Coronary artery pattern was not associated with an increased risk of death. Compared with usual coronary anatomy pattern, however, inverted coronary patterns and single right coronary patterns were associated with increased incidence of delayed sternal closure (p = 0.003) and longer duration of mechanical ventilation (p = 0.008). In a multivariate logistic regression model using only preoperative variables, aortic arch repair at a separate procedure before ASO and smaller birth weight were independent predictors of early mortality. In a second model that included both pre- and intraoperative variables, circulatory arrest time and right ventricular hypoplasia were independent predictors of early death. CONCLUSIONS: The ASO can be performed in the current era without excess early mortality related to uncommon coronary artery patterns. Aortic arch repair before ASO, right ventricular hypoplasia, lower birth weight and longer intraoperative support continue to be independent risk factors for early mortality after the ASO.


Subject(s)
Double Outlet Right Ventricle/surgery , Postoperative Complications/mortality , Transposition of Great Vessels/surgery , Abnormalities, Multiple/mortality , Abnormalities, Multiple/surgery , Coronary Vessel Anomalies/mortality , Coronary Vessel Anomalies/surgery , Double Outlet Right Ventricle/mortality , Female , Heart Defects, Congenital/mortality , Heart Defects, Congenital/surgery , Hospital Mortality , Humans , Infant , Infant, Newborn , Male , Prospective Studies , Risk Factors , Survival Rate , Transposition of Great Vessels/mortality
17.
Am J Med Genet ; 86(5): 470-6, 1999 Oct 29.
Article in English | MEDLINE | ID: mdl-10508990

ABSTRACT

Long QT syndrome (LQTS) is a heterogeneous disorder caused by mutations of at least five different loci. Three of these, LQT1, LQT2, and LQT5, encode potassium channel subunits. LQT3 encodes the cardiac-specific sodium channel, SCN5A. Previously reported LQTS-associated mutations of SCN5A include a recurring three amino acid deletion (DeltaKPQ1505-1507) in four different families, and four different missense mutations. We have examined the SCN5A gene in 88 index cases with LQTS, including four with Jervell and Lange-Nielsen syndrome and the remainder with Romano-Ward syndrome. Screening portions of DIII-DIV, where mutations have previously been found, showed that none of these patients has the three amino acid deletion, DeltaKPQ1505-1507, or the other four known mutations. We identified a novel missense mutation, T1645M, in the DIV; S4 voltage sensor immediately adjacent to the previously reported mutation R1644H. We also examined all of the additional pore-forming regions and voltage-sensing regions and discovered another novel mutation, T1304M, at the voltage-sensing region DIII; S4. Neither T1645M nor T1304M were seen in a panel of unaffected control individuals. Five of six T1304M gene carriers were symptomatic. In contrast to previous studies, QT(onset-c) was not a sensitive indicator of SCN5A-associated LQTS, at least in this family. These data suggest that mutations of SCN5A are responsible for only a small proportion of LQTS cases.


Subject(s)
Long QT Syndrome/genetics , Mutation, Missense , Sequence Deletion , Sodium Channels/genetics , Adolescent , Adult , Amino Acid Substitution , Chromosome Mapping , Female , Genetic Variation , Humans , Long QT Syndrome/physiopathology , Male , Models, Molecular , NAV1.5 Voltage-Gated Sodium Channel , Pedigree , Protein Structure, Secondary , Sodium Channels/chemistry
18.
Ann Thorac Surg ; 69(1): 186-92, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10654511

ABSTRACT

BACKGROUND: The present study examines the long-term outcome of pediatric patients with cardiac disease who required mechanical circulatory support with extracorporeal membrane oxygenation or ventricular assist devices. METHODS: Telephone interviews and questionnaires were administered to parents and physicians of pediatric cardiac patients who were in-hospital survivors after requiring mechanical circulatory support, with either extracorporeal membrane oxygenation or ventricular assist devices. Data was collected regarding these patients' general health, cardiac status, and neurologic outcome, and compared between the two modes of support. RESULTS: Follow-up was available for 26 patients supported with extracorporeal membrane oxygenation (25 survivors, 96%) and 11 patients supported with ventricular assist devices (10 survivors, 91%); median follow-up 42 months, 11 to 92 months). More than 80% of survivors were in New York Heart Association class I or II. Of 31 patients for whom neurologic assessment data was available, moderate to severe neurologic impairment was more common for extracorporeal membrane oxygenation supported patients [13 of 21, 59%) than for ventricular assist device supported patients (2 of 10, 20% p = 0.03). Neurologic impairment was associated with small patient size and the use of circulatory arrest during cardiac surgical repair, but was not associated with in-hospital neurologic complications, carotid cannulation, or presupport cardiac arrest. CONCLUSIONS: The long-term survival and cardiac functional status of pediatric cardiac patients requiring mechanical circulatory support is favorable. Extracorporeal membrane oxygenation supported patients demonstrate higher rates of neurologic impairment than patients supported with ventricular assist devices. Poor neurologic outcomes are associated with institution of support in younger patients with more complex congenital heart disease.


Subject(s)
Extracorporeal Membrane Oxygenation , Heart Diseases/therapy , Heart-Assist Devices , Adolescent , Adult , Body Constitution , Chi-Square Distribution , Child , Child Development , Child, Preschool , Follow-Up Studies , Health Status , Heart/physiopathology , Heart Arrest, Induced , Heart Defects, Congenital/surgery , Heart Diseases/physiopathology , Heart Diseases/surgery , Humans , Infant , Interviews as Topic , Longitudinal Studies , Neurologic Examination , Surveys and Questionnaires , Treatment Outcome
19.
Ann Thorac Surg ; 70(3): 890-4, 2000 Sep.
Article in English | MEDLINE | ID: mdl-11016329

ABSTRACT

BACKGROUND: Neutrophil adhesion to endothelium contributes to myocardial reperfusion injury after cardiac operation. Initial neutrophil-endothelial interactions involve selectins, which bind Sialyl-LewisX on neutrophils. Blockade of selectin-mediated neutrophil-endothelial interactions with CY-1503, a synthetic analogue of Sialyl-LewisX, might reduce reperfusion injury after myocardial ischemia. METHODS: The efficacy of CY-1503 to attenuate global myocardial reperfusion injury was assessed in isolated blood-perfused neonatal lamb hearts that had 2 hours of cold cardioplegic ischemia. CY-1503 (40 mg/L) or saline vehicle was added to blood perfusate before ischemia. Contractile function (developed pressure, dP/dt) and coronary vascular endothelial function (acetylcholine response) were assessed at base line and during reperfusion. Myocardial neutrophil accumulation was assessed by myeloperoxidase quantification. RESULTS: Compared to controls, treatment with CY-1503 improved recovery of all indices of contractile function, preserved coronary vascular endothelial function, and reduced myocardial neutrophil accumulation. CONCLUSIONS: In isolated neonatal lamb hearts that underwent hypothermic cardioplegic ischemia, CY-1503 administration reduced myocardial neutrophil accumulation and preserved endothelial and contractile function. Selectin blockade of leukocyte-endothelial interactions might attenuate reperfusion injury and enhance myocardial protection during cardiac surgical procedures.


Subject(s)
Endothelium, Vascular/drug effects , Heart/drug effects , Lewis Blood Group Antigens , Myocardial Reperfusion Injury/prevention & control , Oligosaccharides/pharmacology , Vasodilation/drug effects , Animals , Animals, Newborn , Endothelium, Vascular/physiology , Heart/physiology , In Vitro Techniques , Myocardial Contraction/drug effects , Neutrophils/cytology , Oligosaccharides/therapeutic use , Peroxidase/analysis , Sheep
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