RESUMEN
Mexico produces more than four million tons of tomato fruits and ranks tenth worldwide. In February 2022, tomato plants in a greenhouse in Culiacan, Sinaloa State, were affected by wilt diseases with an incidence of 20% and irreversible wilt and death of the infected plants (severity up 70%). When cut stems from affected plants, a reddish to brown discoloration of the vascular system was observed and these were disinfected with 1% NaClO for 5 min and then placed in a humid chamber. Characteristic milky-white exudate was obtained. From that exudate, irregular, mucoid, and white colonies with pink centres were obtained on casamino peptone glucose (CPG) plates supplemented with 1% 2,3,5-triphenyl 15 tetrazolium chloride (TZC); these characteristics are typical of the Ralstonia solanacearum species complex (RSSC) (Garcia et al., 2019). Identification of the pathogen was done by PCR using specific primer pairs reported by Paudel et al. (2022), RssC-wF3 (5'-TATATATCCTCGACTTTTCCATGAAGCTGTG-3') - RssCwR3 (5'-CTATATATATACCCCACTTGTTGAGGAACTG-3') and Rpseu-wF5 (5'-TTTTATTTTTTTGGTGTCCGGGCCAAGATAG-3') - Rpseu-wR5 (5'- TTATATTACTCGAACGTGCTGCAAAACCACT-3'), which amplified fragments of 162 and 251 bp for RSSC and Ralstonia pseudosolanacearum, respectively. Additionally, 759 (5'-GTCGCCGTCAACTCACTTTCC-3') - 760 (5'-GTCGCCGTCAGCAATGCGGAATCG-3') (Opina, et al., 1997) and Nmult21:1F (5'-CGTTGATGAGGCGCGCAATTT-3') - Nmult22:RR (5'- TCGCTTGACCCTATAACGAGTA-3') (Fegan and Prior, 2005) were used to generate 282 and 144 bp amplicons for RSSC and phylotype I, respectively. Subsequen to making the specific detection, the representative strain ClnMx was used to generate a sequence for the endoglucanase (egl) gene for separation into sequevars by using the primers Endo-F (5'- ATGCATGCCGCTGGTCGCCGC-3') and Endo-R (5'-GCGTTGCCCGGCACGAACACC-3'), which amplified a fragment of 750 bp (Fegan et al., 1998). The egl sequence (GenBank Access ON542479) showed 100% identity with the well-defined R. pseudosolanacearum sequevar 14, which was isolated from tomato plants from Senegal (UW763, I-14 GenBank Access CP051174) (Steidl et al., 2021), as well as, the strain MAFF 301070 (GenBank Access AB508612) from Japanese tomato. For pathogenicity tests, four 1-month-old tomato plants were infected using an insulin syringe that contained a pure bacterial suspension with approximately 2x108 CFU/mL. For each plant, 20 µL was infiltrated into the axil of the third upper leaf, and for untreated controls, tomato plants were infiltrated with sterile water. All plants were kept at 28°C under greenhouse conditions. Symptoms resembling those observed in the field were observed in inoculated plants six days after inoculation, and the plant pathogen was recovered on TZC medium. To confirm the bacteria identification a PCR using the specific primer pairs mentioned early was carried out. In contrast, water-treated control plants remained healthy. Koch's postulates were carried out twice with similar results. Ralstonia solanacearum species complex (RSSC) causes severe economic losses in many countries of the world because of their capability to infect a wide range of host plants, including potato, tomato, eggplant, tobacco, and, banana, among others. Ralstonia pseudosolanacearum has been reported to cause tomato wilt disease mainly on the Afro-Eurasian continent in areas such as Senegal, Cambodia, and Japan (Klass et al., 2019). To our knowledge, this is the first report of R. pseudosolanacearum causing bacterial wilt diseases in tomato plants from Mexico and because, the control of this bacteria is a challenge by the long survival time in soil, water, and infected plant tissues, the identification of this important pathogen could provide relevant information for developing management strategies.
RESUMEN
In December 2022, blossom blight, abortion, and soft rot of fruits were observed on Cucurbita pepo L. var. Zucchini in Mexico under greenhouse conditions (temperatures of 10 to 32°C and relative humidity up to 90%). The disease incidence in about 50 plants analyzed was around 70% with a severity of nearly 90%. Mycelial growth on flower petals and fruit rot with brown sporangiophores was observed. Ten disinfested fruit tissues in 1% NaClO for 5 min and then rinsed twice in distilled water from the lesion edges were placed on potato dextrose agar culture medium (PDA) supplemented with acid lactic and then, the morphological characterization was carried out in V8 agar medium. After 48 h of growth at 27°C, the colonies were pale yellow with diffuse cottony mycelia that were non-septate and hyaline and produced both sporangiophores bearing sporangiola and sporangia. The sporangiola were brown, ranged from ellipsoid to ovoid, and had longitudinal striations that measured 22.7 to 40.5 (29.8) µm x 16.08 to 21.9 (14.5) µm long and wide, respectively (n=100). The sporangia were subglobose, had a diameter of 127.2 to 281.09 (201.7) µm (n=50), and contained ovoid sporangiospores that measured 26.5 to 63.1 (46.7) µm x 20.07 to 34.7 (26.3) µm long and wide, respectively (n=100) which had hyaline appendages at the ends. Based on these characteristics, the fungus was identified as Choanephora cucurbitarum (Ji-Hyun et al. 2016). For molecular identification, DNA fragments for the internal transcribed spacer (ITS) and the large subunit rRNA 28S (LSU) regions for two representative strains (CCCFMx01 and CCCFMx02) were amplified and sequenced with the primer pairs ITS1-ITS4 and NL1-LR3 (White et al. 1990; Vilgalys and Hester 1990). The ITS and LSU sequences were deposited in GenBank database (Accession numbers OQ269823-24 and OQ269827-28, respectively) for both strains. The Blast alignment showed from 99.84 to 100% identity with Choanephora cucurbitarum strains JPC1 (MH041502, MH041504), CCUB1293 (MN897836), PLR2 (OL790293), and CBS 178.76 (JN206235, MT523842). To confirm the specie identification, the evolutionary analyses were conducted from the concatenated sequences of the ITS and LSU of C. cucurbitarum and other mucoralean species with the Maximum Likelihood method and Tamura-Nei model included in the software MEGA11. The pathogenicity test was demonstrated using five surface-sterilized zucchini fruits inoculated with a sporangiospores suspension containing a concentration of 1 x 105 esp/mL on two sites per fruit (20 µL each) that previously were wounded with a sterile needle. For fruit control, 20 µL of sterile water was used. Three days after inoculation under humidity conditions at 27°C, white mycelia and sporangiola growth with a soaked lesion were observed. That fruit damage was not observed on the control fruits. C.cucurbitarum was reisolated from lesions on PDA and V8 medium which was confirmed by morphological characterization fulfilling Koch's postulates. Blossom blight, abortion, and soft rot of fruits caused by C. cucurbitarum were observed on Cucurbita pepo and C. moschata in Slovenia and Sri Lanka (Zerjav and Schroers 2019; Emmanuel et al. 2021). This pathogen has the capability to infect a wide variety of plants worldwide (Kumar et al. 2022; Ryu et al. 2022). There are no reports of C. cucurbitarum causing agricultural losses in Mexico, and this is the first report causing the disease symptoms in Cucurbita pepo in this country; however, this fungus was found in the soil of papaya-producing areas and it is considered an important plant pathogenic fungus. Therefore, strategies for their control are highly recommended to avoid spreading the disease (Cruz-Lachica et al. 2018).
RESUMEN
Bacterial wilt caused by the Ralstonia solanacearum species complex (RSSC) is a major disease of solanaceous crops worldwide. In May 2022, symptoms of wilting, yellowing, and reduced growth were observed on eggplant (Solanum melongena) cv. Barcelona in a commercial greenhouse located in Culiacán, Sinaloa, Mexico. The disease incidence was recorded up to 30%. Sections of stems from diseased plants showed discoloration of the vascular tissue and the pith. Colonies with typical RSSC morphology were isolated from five eggplant stems on Petri plates containing casamino acid-peptone-glucose (CPG) medium supplemented with 1% 2,3,5-triphenyltetrazolium chloride (TZC), and incubated at 25°C for 48-h (Schaad et al. 2001; Garcia et al. 2019). On CPG medium + TZC, white and irregular colonies with pinkish centers were observed. On King's B medium, mucoid and white colonies were produced. The strains were Gram-negative in the KOH test and were nonfluorescent on King's B medium. Strains were positive using commercial Rs ImmunoStrip® (Agdia, USA). For molecular identification, DNA was extracted, and the partial endoglucanase gene (egl) was amplified by PCR and sequenced using the primer pair Endo-F/Endo-R (Fegan and Prior 2005). BLASTn searches showed 100% identity with available sequences of R. pseudosolanacearum from Musa sp. in Colombia (MW016967) and from Eucalyptus pellita in Indonesia (MW748363, MW748376, MW748377, MW748379, MW748380, MW748382). To confirm the bacterial identity, DNA was amplified with the primers 759/760 (Opina et al. 1997) and Nmult21:1F/Nmult22:RR (Fegan and Prior 2005) to generate 280 and 144-bp amplicons for RSSC and phylotype I (= R. pseudosolanacearum), respectively. A phylogenetic analysis was performed using the Maximum Likelihood method and the strain was distinguished as R. pseudosolanacearum sequevar 14. The strain (CCLF369) is currently preserved in the Culture Collection of the Research Center for Food and Development (Culiacán, Sinaloa, Mexico) and the sequence was deposited in GenBank (accession number OQ559102). Pathogenicity tests were performed by injection of 20-µl of a bacterial suspension (108 CFU/ml) at the base of the stem of five eggplants cv. Barcelona. Five plants inoculated with sterile distilled water were used as control. Plants were kept in a greenhouse at 28/37°C (night/day) for 12 days. All inoculated plants exhibited wilting, chlorosis, and necrosis of leaves between 8 and 11 days after inoculation, whereas control plants remained asymptomatic. The bacterial strain was only isolated from symptomatic plants and confirmed to be R. pseudosolanacearum using the molecular techniques mentioned above, fulfilling Koch´s postulates. Ralstonia pseudosolanacearum has been previously reported to cause bacterial wilt of tomato in Sinaloa, Mexico (García-Estrada et al. 2023); however, to our knowledge, this is the first report of R. pseudosolanacearum infecting eggplant in Mexico. Further studies on epidemiology and management strategies for this disease are required on vegetable crops in Mexico.
RESUMEN
Cucumber (Cucumis sativus L.) is a fruit crop with high consumption worldwide. Mexico had a cucumber production of 826,485 tonnes in 2019. In December 2020, in a greenhouse in Sinaloa State, 18% of persian cucumber fruits with rot symptoms and the development of cottony white mycelia at both ends were observed similar to those described for Fusarium incarnatum (Garcia-Estrada et al., 2021). Isolation of the causal agent was carried out on PDA medium at 27°C for seven days from disinfested sections of cucumber tissues in NaOCl at 1% for one minute and then rinsed in distilled water. Morphological characterization was carried out on SNA medium, in which cultures was colorless and showed scarcely mycelia growth; however, microconidia were abundant and mainly showed clavate shaped measuring 16.6±2.2 x 5.32±1.0 µm (n=100). The morphological characteristics were similar to those described for Fusarium verticillioides (Nirenberhg, 1981). To confirm the species identity, the internal transcribed spacer (ITS) region and the actin (ACT), ß-tubulin (B-tub), calmodulin (CAL), and translation elongation factor 1-α (TEF1-α) genes were amplified and sequenced from one representative isolate: FPM03. These sequences were submitted to GenBank with the accession number MZ868200 for the ITS region and MZ955274 to MZ955277 for the ACT, B-tub, CAL, and TEF1-α regions. BLASTn analysis of the sequences showed 99 to 100% identity with several F. verticillioides sequence accession numbers MG515226, KU603765, MW402311, MW402449, and MW402113, which corresponded to strains CM1, CBS 576.78, and CBS 218.76. To evaluate Koch's postulates, ten healthy cucumber fruits were disinfected with 1% NaOCl for one min and then washed with distilled water. The fruits were inoculated with a single-spore suspension (3 × 104 conidia/mL) by spraying, as well as, five two-month-old cucumber plants. For controls, ten cucumber fruits and five plants were sprayed with sterile distilled water. All fruits were incubated in plastic bags at 25°C for four days and plants were placed under greenhouses conditions for a week. At 30 h after inoculation, all inoculated fruits showed soft rot symptoms at the fruit poles, and the development of white and cottony mycelia was observed at 48 h. Inoculated plants showed the symptoms mainly in the flower end of the fruits after three days. The symptoms observed under laboratory conditions were similar to those registered initially in the field. Samples of rotted tissues (fruit ends and flowers) from inoculated fruits were cultured on PDA medium; the resultant colonies showed similar characteristics to those obtained initially and the same pathogen was recovered. All control fruits and plants remained healthy, confirming pathogenicity. Fusarium verticillioides is primarily a maize pathogen causing stalk and ear rots globally, resulting in significant yield losses and reductions in grain quality; besides, this species produces large amounts of fumonisin B1 with high toxigenicity and is frequently found as food contaminant (Leslie and Sumerell, 2006). In addition, this pathogen was reported to affect sweet sorghum in Spain and banana in Jordan (Palmero et al., 2012; Salem et al., 2020). Recently, in Mexico, F. incarnatum was reported to cause soft rot in cucumber fruits (Garcia-Estrada et al., 2021); however, this is the first report of F. verticillioides affecting Mexican cucumber production. This information will be relevant for disease prevention and control.
RESUMEN
Missense and frameshift pathogenic variants and microdeletions involving TBL1XR1 gene have been described in patients with intellectual disability, autism, Rett-like features and schizophrenia, some of them with the clinical diagnosis of Pierpont syndrome, a rare pattern of multiple congenital anomalies, but others without dysmorphic findings or with non-specific ones, and also patients with only some of the features associated with Pierpont syndrome. We here present a case with a de novo novel missense variant in TBL1XR1 gene with overlapping features with Pierpont syndrome and autism, a neurobehavioral manifestation not previously reported in Pierpont syndrome. This patient expands the phenotypic spectrum of TBL1XR1 gene pathogenic variants.
Asunto(s)
Trastorno Autístico/genética , Discapacidad Intelectual/genética , Mutación Missense/genética , Receptores Citoplasmáticos y Nucleares/genética , Proteínas Represoras/genética , Preescolar , Humanos , Masculino , FenotipoRESUMEN
Watermelon is an important vegetable crop in Mexico and produced on 358,105 ha, with nearly 1.5 x 106 tons. In September 2019, brown, irregular shape to round lesions with concentric rings were observed on the leaves and stems of watermelon plants in Sonora State. The surface of the lesions contained abundant cup-shaped sporodochia covered by masses of olive-green to black conidia. Edge sections of symptomatic tissues were cut from the leaves, disinfected in 70% ethanol for 1 min and subsequently washed twice with distilled water. Disinfected tissue samples were transferred to PDA medium and incubated at 27°C for 15 days. White colonies were observed with spordochia arranged in concentric rings with characteristic of greenish-black masses of conidia. Spore masses stained with lactophenol blue were examined microscopically. Conidia were nonseptate and rod-shaped with rounded ends that measured 6.65 ± 0.54 x 1.56 ± 0.25 µm (n = 100). The characteristics of the fungus were similar to those reported for Paramyrothecium foliicola (Rennberger and Keinath, 2020). Molecular identification was performed on a representative isolate. RNA polymerase II second largest subunit (RPB2), calmodulin (CmdA) and the ß-tubulin (B-tub) genes were amplified and sequenced with the primer sets RPB2-5F2-RPB2-7cR, CAL228F-CAL737R and Bt2a-Bt2b, respectively. These sequences were submitted to GenBank with the acc. nos. MW116070 for RPB2, MW116071 for CmdA and MW116072 for B-tub. BLASTn analysis of the sequences demonstrated 99.34 to 100% identity with Paramyrothecium foliicola (acc. nos. MN398043, MN593713 and MN398138). Koch's postulates were verified on 15-day-old watermelon seedlings and mature fruit. One point of each of ten watermelon seedlings and six points of each of five fruit were marked for inoculation. A plug of mycelium obtained from a monosporic pure culture (grown for 15 days in PDA) was applied to each point without wounds. PDA only medium was included as the controls. The pathogenicity tests were repeated twice. Treated seedlings and fruit were kept in plastic bags at 27°C for 15 days. The first symptoms appeared 4 days after inoculation on the seedlings and 3 days after inoculation on the fruit. At the end of the test, the symptoms were similar to those observed initially in the field. The pathogen was re-isolated from lesion edges, and the morphological characteristics of the pathogen were determined to correspond with those of the inoculated fungus. Control seedlings and fruits remained healthy. P. foliicola has been reported to cause leaf spot disease on wild rocket and basil (Matic et al., 2019) and, recently, on watermelon in South Carolina (Rennberger and Keinath, 2020). To the best of our knowledge, this report is the first to describe P. foliicola causing leaf spot and stem canker on watermelon in Mexico.
RESUMEN
Eggplant (Solanum melongena L.) is an important solanaceous crop that is produced mainly in tropical and subtropical regions and is widely consumed worldwide. In 2018, eggplant production in Mexico was approximately 80000 t, and Sinaloa State contributed 96% of this production; however, this crop suffers significant losses from plant pathogens. In December 2019, fruits from commercial orchards (geographical coordinates: 24°45'39.39''N, 107°26'57.30''O) with visible brown soft rot and profuse white mycelia were analysed. On V8 medium, pieces of tissue obtained from the border of lesions were plated and incubated between 25°C and 36°C. After five days, a dense cottony mycelium with a slightly petaloid pattern was observed at 25°C and did not grow at 36°C. Isolates of that pathogen were heterothallic, and microscopic preparations showed development of coenocytic mycelium and spheroid sporangia that were noncaducous and papillate, measuring 35.6 ± 5.8 x 27.1 ± 4.4. Based on morphological characteristics, the eggplant soft rot causal agent was identified as Phytophthora nicotianae Breda de Haan (Erwin and Ribeiro, 1996). From a representative isolate denominated PhySm01, two DNA regions (internal transcribed spacer (ITS) and the large subunit ribosomal (28S)) were amplified and sequenced with ITS1-ITS4 and NL1-LR3 primers, respectively. The obtained ITS sequence (GenBank accession number MT508842) showed 100% identity with several P. nicotianae sequences (Access MT065840, MH290435 and MG570057) with 100% query coverage and 740 matching nucleotides. For the 28S sequence (accession number MT508843), the identity with strains N° Access EU080889 and EU080508 of P. nicotianae was 99.86%, with 100 query coverage and 729 matching nucleotides. Further, phylogenetic analysis from P. nicotianae strain PhySm01 and GenBank reference sequences was carried out by Maximum Likelihood method with Mega 7 software based on the ITS sequences, which verified the species identification. To fulfill Koch's postulates, a suspension containing 1 x 104 zoospores/mL of the oomycete isolated from the original diseased eggplant fruit was used to inoculate ten healthy and disinfested fruits. Sterile water was used as a control. Three wounds per fruit were made with a sterile needle, and 20 µL of the zoospore suspension (or water) was placed on each. All fruits were placed into plastic bags with moistened paper and incubated at 25°C for three days. Thisest was repeated twice with similar results. Initial symptoms developed 24 hours after inoculation with brown soft tissue forming around the inoculated area, and profuse soft rot accompanied by white mycelium was observed two days after inoculation. No symptoms developed on the control fruits during this time. Pieces of necrotic tissue were plated on V8 medium and incubated as described previously. The reisolated pathogen was compared to the original isolate and had the same morphological characteristics. Phytophthora nicotianae has a worldwide distribution and can infect multiple solanaceous crops, including tobacco (Gallup et al., 2018). In addition, it has been reported on other hosts outside of the Solanaceae family, causing economically important losses in citrus and strawberry. In India, it causes necrosis of citrus fruits and roots, leading to tree decline (Das et al., 2016), and in the United States, it causes crown rot of strawberry (Marin et al., 2018). In Mexico, P. nicotianae has been reported on vinca (Alvarez-Rodriguez et al., 2013); however, this is the first report of P. nicotianae causing fruit soft rot of eggplant, and this pathogen represents a new threat when the environment is favourable for disease outbreaks. References Alvarez-Rodriguez, B. et al. 2013. Plant Dis. 97: 1257. https://doi.org/10.1094/PDIS-04-13-0400-PDN Das, A. K. et al. 2016. J. Plant Pathol. 98: 55. DOI: 10.4454/JPP.V98I1.038 Erwin, D. C. and Ribeiro, O. K. 1996. Phytophthora Diseases Worldwide. The American Phytopathological Society, St. Paul, MN. 562 Pp. Gallup, C. A. et al. 2018. Plan Dis. 102: 1108. https://doi.org/10.1094/PDIS-02-17-0295-RE Marin, M. V. et al. 2018. Plant Dis. 102:1463. https://doi.org/10.1094/PDIS-08-17-1333-PDN.
RESUMEN
Cucumber (Cucumis sativus L.) is an important vegetable crop for Mexico, which is the fifth highest producer of this crop worldwide. In November 2019, a fruit rot disease characterized by the presence of white mycelial growth at both ends of the fruit was observed with an incidence of approximately 30% in a greenhouse production area in Sinaloa State (geographical coordinates: 24°35'25'' N, 107°26'21'' O). Culture of small disinfected sections from cucumber lesion edges was carried out on PDA medium at 27°C for seven days. Colonies had profuse aerial mycelium that was initially white and became beige with age, and light orange sporodochia were eventually produced. Macroconidia had 3 to 5 septa and were slightly curved and tapered at the apex with a foot shape at one end and measured 25.4±2.5 × 2.8±0.3 µm. Microconidia were fusoid in form mostly with 2 to 4 septa and measured 15.7±2.04 × 2.4±0.25 µm (n= 100). The morphological characteristics of this fungal isolate were similar to those of Fusarium incarnatum (Leslie and Summerell, 2006). To confirm the species identification, the internal transcribed spacer (ITS) region, calmodulin (CAL), ß-tubulin (B-tub) and translation elongation factor 1-α (TEF1-α) genes were amplified and sequenced from two representative isolates: FPM01 and FPM02. These sequences were submitted to GenBank with accession numbers MT387313 and MT387314 for the ITS region, MT410503 and MT410506 for CAL, MT410502 and MT410505 for B-tub and MT410504 and MT410507 for TEF1-α for the FPM01 and FPM02 isolates, respectively. BLASTn analysis of the sequences showed between 99.33 and 100% identity with F. incarnatum sequence accession numbers MH865893, LN901598, AB587036 and MK328877, which corresponded to strains CBS 130313, ITEM 6748, MAFF 236521 and FIAD-1, respectively. Further BLAST searches in the FUSARIUM-ID database indicated that these sequences had between 99.76 and 100% identity with sequences of the F. incarnatum-equiseti species complex (FIESC) (FD_01682, FD_01640 and FD_01643). To fulfill Koch's postulates, healthy cucumber fruits were disinfected with 1% NaOCl for one min and then washed with distilled water. Ten nonwounded cucumber fruits were spray inoculated with a conidial suspension (1 × 103 conidia/mL), and five fruits wounded with a sterilized needle were inoculated with mycelial discs (6 mm) at three sites each. Distilled water and PDA medium discs were used as controls. All fruits were placed into plastic bags with 80% relative humidity and incubated at 25°C for three days. At 24 hours after inoculation (hai), a soft rot symptom was observed at the fruit poles on non-wounded fruits and around the inoculated area of wounded fruits, and white mycelial growth was observed at 48 hai for both cases. All inoculated fruit showed similar symptoms to those observed initially in the field, and the control fruits remained healthy. The cultures obtained from tissues of inoculated fruits were similar to those from the initially obtained isolates, thus confirming pathogenicity. Recently, Fusarium incarnatum has been reported in China, causing fruit rot in muskmelon (Cao et al., 2019) and peach (Zhang et al., 2020) and crown rot and leaf spot in cucumber (Mao et al., 2020; Gao et al., 2020). To our knowledge, this is the first report of cucumber fruit rot caused by F. incarnatum in Mexico.
RESUMEN
Tomato (Solanum lycopersicum L.) is an important vegetable crop in Mexico. During 2015 and 2016, symptoms of stem canker were observed on tomato plants in two greenhouses located in the states of Sinaloa and San Luis Potosi, Mexico. Symptomatic plants exhibited dark brown cankers on stems and brown discoloration of the pith, as well as chlorosis, senescence of leaves, and wilting. At the base of diseased plants, orange-red perithecia were developed. Disease incidence ranged 1-5% in the two greenhouses. Pieces from symptomatic stems were surface disinfested by immersion in a 1% sodium hypochlorite solution for 2 min, rinsed in sterile distilled water, and placed in Petri plates containing acidified potato dextrose agar (APDA). The plates were incubated at 25 ºC for 6 days under a 12-h photoperiod. Fusarium-like colonies were consistently isolated and 10 monoconidial isolates were obtained. A representative isolate of each site was selected for morphological characterization, phylogenetic analysis, and pathogenicity tests. The two isolates were deposited in the Culture Collection of Phytopathogenic Fungi at the Research Center for Food and Development (accession nos. CCLF11 and CCLF12). Colonies on PDA at 25°C for 7 days exhibited moderate and cream aerial mycelium. Microscopic examination showed falciform, hyaline macroconidia (n= 100), 4- to 5-septate, measuring 40 to 75 × 4 to 6 µm. Microconidia (n= 100) were cylindrical, hyaline, 0- to 1-septate, measuring 7.8 to 9.5 × 3.1 to 4.8 µm. Chlamydospores were absent. To further identify the pathogen, total DNA was extracted, and the RNA polymerase's second largest subunit (RPB2) and a portion of the translation elongation factor 1-alpha (TEF1-α) were amplified by polymerase chain reaction (PCR) using the primers 5f2 (Liu et al. 1999)/7cr (Reeb et al. 2004) and EF1-728F/EF1-986R (Carbone and Kohn 1999), respectively. The sequences were deposited in GenBank (accession nos. RPB2: MT263727, MT263728; and TEF1-α: MT249025, MT249026). A phylogenetic analysis was performed by the Maximum Likelihood method with a combined dataset of RPB2 and TEF-1α sequences for Fusarium and Neocosmospora species (Sandoval-Denis and Crous 2018). The phylogenetic tree grouped the two isolates CCLF11 and CCLF12 within the F. striatum clade with 99% of bootstrap support. Pathogenicity of the two isolates was verified by inoculation of colonized PDA plugs (5 mm diameter) on the wounded stem surface of 10 2-month-old tomato plants from cv. Sun 6200. Ten control plants were inoculated with PDA plugs without mycelia. All plants were kept under greenhouse conditions at 25 to 35°C and regularly watered. Symptoms of stem canker were observed on all inoculated plants after 15 days, whereas stems from control plants remained healthy. After 45 days, perithecia were observed on stem cankers. Koch´s postulates were fulfilled when the fungus was re-isolated from the stems of inoculated plants and not from control plants. Fusarium striatum has been previously reported causing stem canker of tomato in greenhouses in Canada and the USA (Moine et al. 2014). To our knowledge, this is the first report of F. striatum causing stem canker of tomato in Mexico. This fungal pathogen represents a severe threat and has the potential to cause significant yield losses in tomato greenhouses, so further research is required to define effective management strategies.
RESUMEN
INTRODUCTION: The published evidence on the association between magnesium sulphate (MgSO4) and delayed passage of meconium (DPM) is contradictory. OBJECTIVES: To determine whether there is an association between the administration of MgSO4 to the mother and DPM in the neonate, and to analyse serum magnesium levels in neonates in relation to the cumulative dose of MgSO4 administered to the mother. POPULATION AND METHODS: Retrospective and prospective descriptive and analytical study conducted in patients delivered at or before 32 weeks of gestation in 2 tertiary care hospitals. Delayed passage of meconium was defined as failure to pass meconium within 48â¯h of birth and/or need for rectal stimulation on 2 or more occasions to pass stool and/or interval of at least 48â¯h between the first and second bowel movements. RESULTS: The study included 283 patients (204 retrospectively and 79 prospectively), of who 152 (53.7%) experienced DPM. Delayed passage of meconium was not associated with antenatal MgSO4 administration, the cumulative maternal MgSO4 dose or neonatal serum magnesium levels. Older gestational age (OR, 0.8; confidence interval [CI], 0.69-0.93; Pâ¯=â¯0.003) was an independent protective factor against DPM, while the need for advanced resuscitation (OR, 2.24; CI 1.04-4.86; Pâ¯=â¯0.04) was a risk factor for DPM. CONCLUSION: The neonatal serum levels of magnesium reached with the doses of MgSO4 administered to mothers were not associated with DPM. Lower gestational age and the need for advanced resuscitation were predictors associated with an increased risk of DPM.
Asunto(s)
Sulfato de Magnesio , Magnesio , Recién Nacido , Humanos , Femenino , Embarazo , Sulfato de Magnesio/efectos adversos , Estudios Retrospectivos , Edad Gestacional , MeconioRESUMEN
INTRODUCTION: The resuscitation of the newborn in the delivery room requires high capacities and occurs frequently in an unexpected way. Many professionals trained in pediatrics as pediatric residents will work posteriorly in pediatric units with delivery rooms and will perform neonatal resuscitation only occasionally. Skills acquired in practice or resuscitation courses deteriorate over time. MATERIAL AND METHODS: Descriptive observational study through a survey to pediatricians trained in neonatology at a tertiary hospital in Madrid, and who completed their residency period between 2009 and 2016. Questions about their training in resuscitation and their usual work in the delivery room. RESULTS: Out of 179 surveys sent, 140 pediatricians (78,2%) answered it. 73.6% took a training course in neonatal resuscitation during the residency. There was a progressive increase in the number of residents who did the course during the study period. 74.3% have worked after residency in assistance at birth. 40.7% have taken a refresher course in neonatal resuscitation. CONCLUSIONS: Training in neonatal resuscitation has increased and been consolidated during the training process for pediatric residents. A high percentage of pediatricians work after residency in pediatric units with delivery rooms, less than half of these professionals having been recycled in neonatal resuscitation. Recycling and periodic training seem interesting options to improve the performance of these professionals in the delivery room.
Asunto(s)
Reanimación Cardiopulmonar , Internado y Residencia , Neonatología , Reanimación Cardiopulmonar/educación , Niño , Competencia Clínica , Humanos , Recién Nacido , Neonatología/educación , PediatrasRESUMEN
INTRODUCTION: Magnesium sulphate (MgSO4) therapy has shown to be useful as a neurological protector in the preterm newborn below 32 weeks of gestation. The most documented adverse effect is cardiorespiratory failure, whereas its relationship with meconium obstruction is controversial. The main objective of this study was to analyse the possible association between prenatal MgSO4 therapy and meconium obstruction. PATIENTS AND METHODS: An analytical retrospective study was conducted on <32 weeks preterm babies admitted to a tertiary-level hospital (January 2016-December 2017). Epidemiological, prenatal and postnatal data on the outcomes were obtained, analysed and compared in both groups (exposed to MgSO4 and not exposed). RESULTS: The study included 201 patients (146 exposed and 55 non-exposed). There were no significant differences in the mean gestational age (28.4⯱â¯2.2 vs. 28.7⯱â¯2.8 weeks, respectively), or in the rest of epidemiological and perinatal variables. Prenatal corticosteroid therapy was more frequent in the MgSO4 group (75.9 vs. 53.7%; pâ¯=â¯.002), and in the non-exposed group there were more multiple pregnancies (52.7 vs. 36.6%; pâ¯=â¯.027), and female gender (56.4 vs. 37%; pâ¯=â¯.013). There were no statistically significant differences in the presence of meconium obstruction (75.9% in exposed vs. 67.3% in non-exposed; pâ¯=â¯.23), although repeated rectal stimulation was more frequent in the exposed group (43.2 vs. 27.9%; pâ¯=â¯.08). Furthermore, there were no significant differences in the main cardiorespiratory variables: 1-min Apgar score (6.2 in MgSO4- exposed vs. 5.6 in non-exposed; pâ¯=â¯.75), 5-min Apgar score (7.9 vs. 7.6; pâ¯=â¯.31), advanced newborn resuscitation (26 vs. 31.5%; pâ¯=â¯.44), maximum FiO2 (45.5 vs. 48; pâ¯=â¯.58), and initial inotropic requirements (10.3 vs. 20.8%; pâ¯=â¯.55). CONCLUSIONS: This study found no correlations between MgSO4 therapy and meconium obstruction or cardiorespiratory failure.
Asunto(s)
Obstrucción Intestinal , Sulfato de Magnesio , Femenino , Edad Gestacional , Humanos , Lactante , Recién Nacido , Obstrucción Intestinal/inducido químicamente , Obstrucción Intestinal/etiología , Sulfato de Magnesio/uso terapéutico , Meconio , Embarazo , Estudios RetrospectivosRESUMEN
BACKGROUND: The vertical transmission of severe acute respiratory coronavirus-2 (SARS-CoV-2) remains highly debated. Here, we evaluated SARS-CoV-2-transmission in newborns with intrauterine conditions. METHODS: This was a prospective, observational and multicentric study involving 13 Spanish hospitals included in the GEStational and NEOnatal-COVID cohort. Pregnant women with microbiologically confirmed SARS-CoV-2 infection during any trimester of pregnancy or delivery and their newborns were included from March to November 2020. Demographic, clinical and microbiological data were also obtained. Viral loads were analyzed in different maternal and newborn biological samples (placenta, breast milk and maternal blood; urine, meconium and newborn blood). RESULTS: A total of 177 newborns exposed to SARS-CoV-2 were included. Newborns were tested by reverse transcriptase-polymerase chain reaction using nasopharyngeal swabs within the first 24-48 hours of life and at 14 days of life. In total 5.1% were considered to have SARS-CoV-2 infection in the neonatal period, with 1.7% considered intrauterine and 3.4% intrapartum or early postnatal transmission cases. There were no differences in the demographic and clinical characteristics of the pregnant women and their newborns' susceptibility to infections in their perinatal history or background. CONCLUSIONS: Intrauterine transmission of SARS-CoV-2 is possible, although rare, with early postnatal transmission occurring more frequently. Most infected newborns remained asymptomatic or had mild symptoms that evolved well during follow-up. We did not find any maternal characteristics predisposing infants to neonatal infection. All infected newborn mothers had acute infection at delivery.Although there was no presence of SARS-CoV2 in cord blood or breast milk samples, SARS-CoV-2 viral load was detected in urine and meconium samples from infected newborns.
Asunto(s)
COVID-19 , Complicaciones Infecciosas del Embarazo , COVID-19/epidemiología , Femenino , Humanos , Lactante , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa , Embarazo , Complicaciones Infecciosas del Embarazo/diagnóstico , Complicaciones Infecciosas del Embarazo/epidemiología , Estudios Prospectivos , ARN Viral , SARS-CoV-2RESUMEN
OBJECTIVE: The aim of this study is to compare the clinical outcomes at 24 months postmenstrual age of two populations receiving beractant replacement therapy using less invasive surfactant administration (LISA) versus intubation, administration of surfactant, and early extubation (INSURE). Hospital admission requirements, psychomotor development, and respiratory and neurological outcomes were studied. STUDY DESIGN: This was a single-center, retrospective, and descriptive study with a sample of 60 patients (30 for each group) on nasal continuous positive airway pressure during the first 3 days of life, requiring surfactant administration. RESULTS: We found no significant differences between both groups on psychomotor development and respiratory and neurological outcomes. CONCLUSION: Compared to INSURE technique, the administration of surfactant by LISA is feasible and safe and reduces invasive mechanical ventilation exposure with no differences in the follow-up neurodevelopmental and respiratory outcomes at 24 postmenstrual age.
Asunto(s)
Síndrome de Dificultad Respiratoria del Recién Nacido , Tensoactivos , Presión de las Vías Aéreas Positiva Contínua , Humanos , Lactante , Recién Nacido , Recien Nacido Prematuro , Intubación Intratraqueal , Síndrome de Dificultad Respiratoria del Recién Nacido/terapia , Estudios RetrospectivosRESUMEN
INTRODUCTION: Magnesium sulphate (MgSO4) therapy has shown to be useful as a neurological protector in the preterm newborn below 32 weeks of gestation. The most documented adverse effect is cardiorespiratory failure, whereas its relationship with meconium obstruction is controversial. The main objective of this study was to analyse the possible association between prenatal MgSO4 therapy and meconium obstruction. PATIENTS AND METHODS: An analytical retrospective study was conducted on < 32 weeks preterm babies admitted to a tertiary-level hospital (January 2016-December 2017). Epidemiological, prenatal and postnatal data on the outcomes were obtained, analysed and compared in both groups (exposed to MgSO4 and not exposed). RESULTS: The study included 201 patients (146 exposed and 55 non-exposed). There were no significant differences in the mean gestational age (28.4 ± 2.2 vs. 28.7 ± 2.8 weeks, respectively), or in the rest of epidemiological and perinatal variables. Prenatal corticosteroid therapy was more frequent in the MgSO4 group (75.9 vs. 53.7%; p = .002), and in the non-exposed group there were more multiple pregnancies (52.7 vs. 36.6%; p = .027), and female gender (56.4 vs. 37%; p = .013). There were no statistically significant differences in the presence of meconium obstruction (75.9% in exposed vs. 67.3% in non-exposed; p = .23), although repeated rectal stimulation was more frequent in the exposed group (43.2 vs. 27.9%; p = .08). Furthermore, there were no significant differences in the main cardiorespiratory variables: 1-minute Apgar score (6.2 in MgSO4- exposed vs. 5.6 in non-exposed; p = .75), 5-minutes Apgar score (7.9 vs. 7.6; p = .31), advanced newborn resuscitation (26 vs. 31.5%; p = .44), maximum FiO2 (45.5 vs. 48; p = .58), and initial inotropic requirements (10.3 vs. 20.8%; p = .55). CONCLUSIONS: This study found no correlations between MgSO4 therapy and meconium obstruction or cardiorespiratory failure.
RESUMEN
INTRODUCTION: the resuscitation of the newborn in the delivery room requires high capacities and occurs frequently in an unexpected way. Many professionals trained in pediatrics as pediatric residents will work posteriorly in pediatric units with delivery rooms and will perform neonatal resuscitation only occasionally. Skills acquired in practice or resuscitation courses deteriorate over time. MATERIAL AND METHODS: descriptive observational study through a survey to pediatricians trained in neonatology at a tertiary hospital in Madrid, and who completed their residency period between 2009 and 2016. Questions about their training in resuscitation and their usual work in the delivery room. RESULTS: Out of 179 surveys sent 140 pediatricians (78,2%) answered it. 73.6% took a training course in neonatal resuscitation during the residency. There was a progressive increase in the number of residents who did the course during the study period. 74.3% have worked after residency in assistance at birth. 40.7% have taken a refresher course in neonatal resuscitation. CONCLUSIONS: training in neonatal resuscitation has increased and been consolidated during the training process for pediatric residents. A high percentage of pediatricians work after the residency in pediatric units with delivery rooms, less than half of these professionals having been recycled in neonatal resuscitation. Recycling and periodic training seem interesting options to improve the performance of these professionals in the delivery room.
RESUMEN
INTRODUCTION AND OBJECTIVES: Readmission rate is an indicator of the quality of hospital care. The aim of the study is to identify potential preventable factors for paediatric readmission. MATERIAL AND METHODS: A descriptive, analytical, longitudinal, and single centre study was carried out in the Paediatric Hospitalisation ward of a tertiary hospital during the period from June 2012 to November 2015. Readmission was defined as the one that occurs in the first 30 days of previous admission, as very early readmission if it occurs in the first 48hours, early readmission in the 2-7 days, and late readmission if occurs after 7 days. Preventable readmission is defined as one that takes place in the first 15 days and for the same reason as the first admission. Epidemiological and clinical variables were analysed. A univariate and multivariate study was carried out. RESULTS: In the study period, 5,459 patients were admitted to the paediatric hospital, of which 226 of them were readmissions (rate of readmission: 4.1%). When the hospital occupation rate was greater than 70%, the overall percentage of readmissions was significantly higher (8.5% vs 2.5%; P<.001). In the multivariate analysis, it was found that having a chronic disease and the number of visits to emergency care units before admission, are predictive factors of preventable readmission. CONCLUSIONS: The rate of readmissions is greater in the periods of higher care pressure. The readmission of patients with chronic condition is preventable, and therefore strategies must be designed to try to avoid them.