Structural and Biochemical Changes in Salicylic-Acid-Treated Date Palm Roots Challenged with Fusarium oxysporum f. sp. albedinis

Histochemical and ultrastructural analyses were carried out to assess structural and biochemical changes in date palm roots pretreated with salicylic acid (SA) then inoculated with Fusarium oxysporum f. sp. albedinis (Foa). Flavonoids, induced proteins, and peroxidase activity were revealed in root tissues of SA-treated plants after challenge by Foa. These reactions were closely associated with plant resistance to Foa. Host reactions induced after inoculation of SA-treated plants with Foa included the plugging of intercellular spaces, the deposition of electron-dense materials at the sites of pathogen penetration, and several damages to fungal cells. On the other hand, untreated inoculated plants showed marked cell wall degradation and total cytoplasm disorganization, indicating the protective effects provided by salicylic acid in treated plants

Genomic DNA extraction from the medicinal plant Crocus sativus : Optimization of Standard Methods

High-quality genomic DNA is essential for genomic and molecular investigations such as next-generation sequencing. However, DNA extraction from medicinal plants like Crocus sativus can be challenging due to their high secondary metabolite content, which can interact with nucleic acids and affect the quality and yield of extraction. This study aimed to optimize the quality and yield of DNA using the cetyltrimethylammonium bromide (CTAB) extraction method from the leaves, stigma, and saffron corm. This new method is easy to use and can be performed using standard equipment and inexpensive reagents. The modifications made to the CTAB lysis buffer in this study, with the addition of SDS, resulted in a yield of 4233 ng/µl of DNA per sample of saffron corm (100 mg). This protocol is efficient and cost-effective for DNA extraction for studies with large samples and limited resources. This method is expected to be widely used for large-scale plant extraction and has a broad application in PCR-based sequencing studies

Quantification of glycosaminoglycans using harmine extract from Peganum harmala L. in mucopolysaccharidoses researches

Background: Harmine is used in the quantification of glycosaminoglycans (GAGs) for the research on mucopolysaccharidoses (MPSs). Although this product is commercially available, researchers may consider preparing it under laboratory conditions when it is unavailable for various reasons. This research aims to extract harmine from Peganum harmala L. seeds and determine whether this extract can be used as a substitute for pure harmine in the quantification of GAGs and, consequently, in the research on MPS. Methods: P. harmala L. seeds were obtained from the plant and extracted using methanol. The harmine extract was then used in a spectrophotometric assay on controls, including patients known of having MPS and healthy subjects and patients suspected of having different types of MPS. Results: One milligram of harmine extract in 1 ml of ethanol is sufficient to produce the chromogen as that obtained by pure harmine. The chromogen exhibits a peak absorbance peak at 510 nm. The concordance between the two forms of harmine reaches 100%, either for abnormal values seen in GAGs from MPS patients or for normal values in those from healthy controls. Suspicion of having MPS was lifted in investigated patients. The harmine extracted from P. harmala L. seeds allowed for accurate and reproducible quantification of the GAGs. Conclusion: This study demonstrates that harmine extract can be used as a reagent for the quantification of GAGs in the research on MPS when pure harmine is unavailable in the same way as pure harmine

Use of two bacteria for biological control of bayoud disease caused by Fusarium oxysporum in date palm (Phoenix dactylifera L) seedlings

The Bayoud, caused by Fusarium oxysporum f. sp. albedinis (Foa), is the most destructive disease of date palm (Phoenix dactylifera L) in Morocco and Algeria, with no effective control strategy yet available. In this work, two bacteria, Bacillus amyloliquefaciens strain Ag1 (Ag) and Burkholderia cepacia strain Cs5 (Cs), were examined for their potential to control this disease. Both bacterial strains inhibited both growth and sporulation of Foa. They released compounds into the culture medium, which resulted into cytological changes in Foa's mycelial structure. When Jihel-date palm plantlets, a susceptible cultivar, were induced with these bacteria, the size of the necrosis zone, which reflected the spreading of the pathogen, was reduced by more than 70%, as compared with uninduced controls. To further investigate the mechanisms of such disease reduction, phenolic compounds and peroxidase activity were assessed. One month after inoculation, date palm defense reactions against Foa were different depending on the bacterium used, B. cepacia led to higher accumulation of constitutive caffeoylshikimic acid isomers while B. amyloliquefaciens triggered the induction of new phenolic compounds identified as hydroxycinnamic acid derivatives. Peroxidase activity has also been stimulated significantly and varied with the bacterial strain used and with Foa inoculation. These results add to the promising field of investigation in controlling Bayoud disease.PRAD 11-05-Egide N°24172UL and AI (Tunisie-Maroc) 24/0

Propagation of Saffron (<i>Crocus sativus</i> L.) Using Cross-Cuttings under a Controlled Environment

Saffron (Crocus sativus L.) is a valuable geophyte plant and one of the most expensive spices in the world. Recently, the demand for saffron spice has increased in worldwide markets owing to its enormous application and value. However, the production of saffron is limited by the vegetative propagation technique and the limited number of high-quality corms planted. Furthermore, climatic changes, notably increasing temperatures, negatively influence saffron multiplication and growth. Thus, it is important to develop alternative cultivation and propagation techniques for saffron under a controlled environment, which could ensure an increase in saffron yield and avoid the negative impact of climatic changes. The present study aimed to develop an alternative method for vegetative propagation of Crocus sativus under controlled conditions. The effect of different cross-cuttings, including basal cuttings (BCs) and top-to-bottom cuttings (CTBs), was evaluated on shoot, leaf, flower, and daughter corm production. All the growth parameters examined were influenced by the cutting treatment applied. The results showed that the highest number of shoots formed was obtained by BCs and CTBs, with an average of 6.68 and 5.47 shoots per corm, respectively, compared to the control with an average of 2.70 shoots per corm. The cutting treatment positively affected the formation of daughter corms in which, the high mean number of corms recorded was obtained by the BC treatment. Meanwhile, the lower size of the daughter corms was obtained after the cross-cutting treatment. This is the first report that provides an alternative propagation for saffron using a controlled environment, which could help to improve the production of saffron

The role of centre and country factors on process and outcome indicators in critically ill patients with hospital-acquired bloodstream infections

Purpose: The primary objective of this study was to evaluate the associations between centre/country-based factors and two important process and outcome indicators in patients with hospital-acquired bloodstream infections (HABSI). Methods: We used data on HABSI from the prospective EUROBACT-2 study to evaluate the associations between centre/country factors on a process or an outcome indicator: adequacy of antimicrobial therapy within the first 24&nbsp;h or 28-day mortality, respectively. Mixed logistical models with clustering by centre identified factors associated with both indicators. Results: Two thousand two hundred nine patients from two hundred one intensive care units (ICUs) were included in forty-seven countries. Overall, 51% (n = 1128) of patients received an adequate antimicrobial therapy and the 28-day mortality was 38% (n = 839). The availability of therapeutic drug monitoring (TDM) for aminoglycosides everyday [odds ratio (OR) 1.48, 95% confidence interval (CI) 1.03-2.14] or within a few hours (OR 1.79, 95% CI 1.34-2.38), surveillance cultures for multidrug-resistant organism carriage performed weekly (OR 1.45, 95% CI 1.09-1.93), and increasing Human Development Index (HDI) values were associated with adequate antimicrobial therapy. The presence of intermediate care beds (OR 0.63, 95% CI 0.47-0.84), TDM for aminoglycoside available everyday (OR 0.66, 95% CI 0.44-1.00) or within a few hours (OR 0.51, 95% CI 0.37-0.70), 24/7 consultation of clinical pharmacists (OR 0.67, 95% CI 0.47-0.95), percentage of vancomycin-resistant enterococci (VRE) between 10% and 25% in the ICU (OR 1.67, 95% CI 1.00-2.80), and decreasing HDI values were associated with 28-day mortality. Conclusion: Centre/country factors should be targeted for future interventions to improve management strategies and outcome of HABSI in ICU patients

Presentation, management, and outcomes of older compared to younger adults with hospital-acquired bloodstream infections in the intensive care unit: a multicenter cohort study

Purpose: Older adults admitted to the intensive care unit (ICU) usually have fair baseline functional capacity, yet their age and frailty may compromise their management. We compared the characteristics and management of older (≥ 75&nbsp;years) versus younger adults hospitalized in ICU with hospital-acquired bloodstream infection (HA-BSI). Methods: Nested cohort study within the EUROBACT-2 database, a multinational prospective cohort study including adults (≥ 18&nbsp;years) hospitalized in the ICU during 2019-2021. We compared older versus younger adults in terms of infection characteristics (clinical signs and symptoms, source, and microbiological data), management (imaging, source control, antimicrobial therapy), and outcomes (28-day mortality and hospital discharge). Results: Among 2111 individuals hospitalized in 219 ICUs with HA-BSI, 563 (27%) were ≥ 75&nbsp;years old. Compared to younger patients, these individuals had higher comorbidity score and lower functional capacity; presented more often with a pulmonary, urinary, or unknown HA-BSI source; and had lower heart rate, blood pressure and temperature at presentation. Pathogens and resistance rates were similar in both groups. Differences in management included mainly lower rates of effective source control achievement among aged individuals. Older adults also had significantly higher day-28 mortality (50% versus 34%, p &lt; 0.001), and lower rates of discharge from hospital (12% versus 20%, p &lt; 0.001) by this time. Conclusions: Older adults with HA-BSI hospitalized in ICU have different baseline characteristics and source of infection compared to younger patients. Management of older adults differs mainly by lower probability to achieve source control. This should be targeted to improve outcomes among older ICU patients

Epidemiology and outcomes of hospital-acquired bloodstream infections in intensive care unit patients: the EUROBACT-2 international cohort study

Purpose In the critically ill, hospital-acquired bloodstream infections (HA-BSI) are associated with significant mortality. Granular data are required for optimizing management, and developing guidelines and clinical trials. Methods We carried out a prospective international cohort study of adult patients (≥ 18 years of age) with HA-BSI treated in intensive care units (ICUs) between June 2019 and February 2021. Results 2600 patients from 333 ICUs in 52 countries were included. 78% HA-BSI were ICU-acquired. Median Sequential Organ Failure Assessment (SOFA) score was 8 [IQR 5; 11] at HA-BSI diagnosis. Most frequent sources of infection included pneumonia (26.7%) and intravascular catheters (26.4%). Most frequent pathogens were Gram-negative bacteria (59.0%), predominantly Klebsiella spp. (27.9%), Acinetobacter spp. (20.3%), Escherichia coli (15.8%), and Pseudomonas spp. (14.3%). Carbapenem resistance was present in 37.8%, 84.6%, 7.4%, and 33.2%, respectively. Difficult-to-treat resistance (DTR) was present in 23.5% and pan-drug resistance in 1.5%. Antimicrobial therapy was deemed adequate within 24 h for 51.5%. Antimicrobial resistance was associated with longer delays to adequate antimicrobial therapy. Source control was needed in 52.5% but not achieved in 18.2%. Mortality was 37.1%, and only 16.1% had been discharged alive from hospital by day-28. Conclusions HA-BSI was frequently caused by Gram-negative, carbapenem-resistant and DTR pathogens. Antimicrobial resistance led to delays in adequate antimicrobial therapy. Mortality was high, and at day-28 only a minority of the patients were discharged alive from the hospital. Prevention of antimicrobial resistance and focusing on adequate antimicrobial therapy and source control are important to optimize patient management and outcomes