Meropenem versus piperacillin-tazobactam for the treatment of pancreatic necrosis.

PURPOSE: To date, there are three published guidelines discussing management of infected pancreatic necrosis (IPN) with conflicting recommendations. Specifically, The World Society of Emergency Surgery lists piperacillin-tazobactam as a treatment option in addition to meropenem and ciprofloxacin plus metronidazole. Piperacillin-tazobactam may serve as an effective carbapenem-sparing alternative. Although previous studies shed light on antimicrobial penetration data, there is a lack of clinical data comparing piperacillin-tazobactam to meropenem. The purpose of this study is to compare the efficacy of meropenem and piperacillin-tazobactam for the treatment of IPN. METHODS: This was a multicenter, retrospective cohort study conducted across three institutions. Patients with IPN who received either meropenem or piperacillin-tazobactam from January 2015 to December 2020 were included. The primary composite outcome was the incidence of 90-day clinical failure, which encompassed 90-day all-cause mortality and 90-day intra-abdominal infection recurrence. Secondary outcomes included length of hospital stay, antimicrobial duration of therapy, and the need for surgical intervention. RESULTS: We identified 229 patients with IPN that received either meropenem or piperacillin-tazobactam during hospital admission. After screening, 63 patients were included in the study. Incidence of 90-day clinical failure was observed in 33 % of the meropenem group and 50 % in the piperacillin-tazobactam group (OR, 1.98; 95 % CI 0.57 to 7.01, p = 0.259). The meropenem group had a lower incidence of 90-day infection recurrence in the piperacillin-tazobactam group (56 % vs 29 %, p = 0.047). CONCLUSIONS: Piperacillin-tazobactam may be an efficacious carbapenem-sparing treatment alternative for infected pancreatic necrosis.

Nontargeted Metabolite Profiling of the Most Prominent Indian Mango (Mangifera indica L.) Cultivars Using Different Extraction Methods.

Aroma has a crucial role in assessing the quality of fresh fruit and its processed versions, which serve as reliable indications for advancing local cultivars in the mango industry. The aroma of mango is attributed to a complex of hundreds of volatile, polar, and nonpolar metabolites belonging to different chemical classes like monoterpenes, sesquiterpenes, nonterpene hydrocarbons (alkanes), alcohols, esters, fatty acids, aldehydes, lactones, amides, amines, ethers, and many more. This study looked at the volatile, nonpolar, and polar metabolites from 16 mango cultivars to determine their relative quantities and intervarietal changes using hexane, ethanol, and solid-phase microextraction (SPME), followed by gas chromatography-mass spectrometry (GC-MS) analysis. In total, 58 volatile compounds through SPME, 50 nonpolar metabolites from hexane extract, and 52 polar metabolites from ethanol extract were detected from all of the cultivars, belonging to various chemical classes. Through the SPME method, all 16 mango cultivars except Dashehari and Neelum exhibited abundant monoterpenes with maximum concentration in Kesar (91.00%) and minimum in Amrapali (60.66%). However, the abundance of fatty acids and sesquiterpenes was detected in Dashehari (37.91%) and Neelum (74.80%), respectively. In the hexane extract, 23 nonterpene hydrocarbons exhibited abundance in all 16 mango cultivars except Baneshan, with a higher concentration in Dashehari (95.45%) and lower in Ratna (77.63%). The ethanol extraction of 16 mango cultivars showed a higher concentration of esters, aldehydes, alcohols, and amides in Jamadar (52.16%), Dadamio (74.30%), Langra (64.38%), and Kesar (37.10%), respectively. There have been a lot of metabolite variations observed and analyzed using hierarchical cluster analysis (HCA) and principal component analysis (PCA) based on the similarity of various chemical compounds. Cluster analysis revealed the true similarity and pedigree of different mango cultivars, viz., Neeleswari, Dashehari, Neelum, Alphonso, Baneshan, Sonpari, and Neeleshan. They occupied the same cluster during analysis.

Oral antibiotic step-down therapy for nonstaphylococcal gram-positive bloodstream infections.

Bloodstream infections traditionally are treated with intravenous (IV) therapy. This study's purpose is to evaluate if oral step-down therapy is noninferior to IV therapy for gram-positive bloodstream infections (GP-BSIs). This retrospective cohort study included patients who received IV therapy and those who received oral step-down therapy for a nonstaphylococcal GP-BSI from 2017 to 2019. The primary endpoint was a composite outcome of 90-day all-cause mortality and clinical failure. A total of 308 patients were included (n = 94, oral; n = 214, IV). The oral step-down group had a lower incidence of 90-day clinical failure (9% vs 14%; P < 0.001). The IV group had a longer hospital stay (4 vs 6 days, P < 0.001); however, there were no significant differences in secondary outcomes. Bivariate analysis found no predictors of 90-day clinical failure. Oral step-down therapy was found to be noninferior to IV therapy.

Dissipation kinetics and health risk assessment of certain insecticides applied in/on tomato under open field and poly-house conditions.

In this study, the dissipation kinetics and health risk assessment of different insecticides in tomato under open field and poly-house conditions were investigated. A total of four insecticides, namely Chlorantraniprole 18.5 SC @ 30 g a.i ha-1, Flubendiamide 20% WG @ 48.0 g a.i ha-1, Indoxacarb 14.5 SC @ 60.0 g a.i ha-1, and Thiamethoxam 25% WG @ 50.0 g a.i ha-1, were applied on tomato at the 50% flowering stage, followed by 10 days after the first spray. Prior to actual sample analysis, QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) based extraction methodology for the chlorantraniliprole, flubendiamide, indoxacarb and thiamethoxam in tomato were verified and quantified on ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) in terms of linearity, sensitivity (detection limits), accuracy (% recovery) and precision (% RSD). The DT50 value of chlorantraniliprole, flubendiamide, indoxacarb and thiamethoxam in tomato under open field condition was 1.95, 2.25, 2.37 and 3.98, respectively and under poly house condition it was 3.05, 5.02, 2.68 and 4.82, respectively. Similarly, the safe waiting period of chlorantraniliprole, flubendiamide, indoxacarb and thiamethoxam in tomato under open field condition was 1.05, 0.83, 2.96 and 3.23, respectively and under poly house condition it was 2.02, 4.93, 4.09 and 7.33, respectively. Further, health risk assessment was evaluated and observed no risk for Indian consumers due to application of studied insecticides (RQ < 1) under open field and poly-house conditions.

Evaluation of Ozonation Technique for Pesticide Residue Removal in Okra and Green Chili Using GC-ECD and LC-MS/MS.

The indiscriminate use of pesticides in agricultural commodities has become a global health concern. Various household methods are employed to remove pesticide residues from agricultural commodities, e.g., water and ozone. Many ozone-based commercial pesticide removal machines are available in the market for the general public. The current study compares the pesticide removal efficiency of ozone-based washing of fruits and vegetables to simple tap water through commercially available machines and its health risk assessment to different age groups of consumers. The okra and green chili fruits were treated with acetamiprid and ethion as foliar application at the fruiting stage, using the recommended dose (RD) and double to the recommended dose (2RD), respectively. A modified QuEChERS-based pesticide extraction method was verified for its accuracy, precision, linearity, and sensitivity. The treated samples were washed with tap and ozonated water at different intervals, i.e., 3, 8, and 10 min using a commercial food purifier. Washing with ozonized water for 3 min recorded the maximum removal of acetamiprid and ethion from okra and chili fruits. Further, the risk quotient values (RQ) obtained were lower than one at both doses. Thus, washing vegetables with ozonized water for 3 min ensures vegetables are safer for general consumption without any health risk to Indian consumers.

Pseudomonas aeruginosa inhibits quorum-sensing mechanisms of soft rot pathogen Lelliottia amnigena RCE to regulate its virulence factors and biofilm formation.

The quorum-sensing (QS) cascade is responsible for the colonization and phenotypic behavior of the pathogenic organism and the regulation of diverse signal molecules. The disruption of the quorum-sensing system is an effective strategy to overcome the possibility of antibiotic resistance development in the pathogen. The quorum quenching does not kill the microbes. Instead, it hinders the expression of pathogenic traits. In the present experiment, Pseudomonas aeruginosa RKC1 was used to extract the metabolites responsible for quorum-sensing inhibition in soft rot pathogen Lelliottia amnigena RCE. During the initial screening, P. aeruginosa RKC1 was found to be most promising and inhibits violacein of Chromobacterium violaceum MTCC2656 pyocyanin, swarming-swimming motility of P. aeruginosa MTCC2297. The characterization of metabolites produced by the microbes which are responsible for quorum-sensing inhibition through GC-MS is very scarce in scientific literature. The ethyl acetate extract of P. aeruginosa RKC1 inhibits biofilm formation of L. amnigena RCE while inhibiting growth at higher concentrations. The GC-MS analysis suggested that Cyclic dipeptides (CDPs) such as Cyclo (L-prolyl-L-valine), Cyclo (Pro-Leu), and Cyclo(D-phenylalanyl-L-prolyl) were predominantly found in the ethyl acetate extract of the P. aeruginosa RKC1 (93.72%). This diketopiperazine (DKPs) exhibited quorum-sensing inhibition against the pathogen in liquid media during the active growth phase and regulated diverse metabolites of the pathogen. Moreover, the metabolites data from the clear zone around wells showed a higher concentration of DKSs (9.66%) compared to other metabolites. So far, very few reports indicate the role of DKPs or CDPs in inhibiting the quorum-sensing system in plant pathogenic bacteria. This is one such report that exploits metabolites of P. aeruginosa RKC1. The present investigation provided evidence to use quorum-sensing inhibitor metabolites, to suppress microbes' pathogenesis and thus develop an innovative strategy to overcome antibiotic resistance.

Quorum Sensing Inhibitory and Quenching Activity of Bacillus cereus RC1 Extracts on Soft Rot-Causing Bacteria Lelliottia amnigena.

The quorum sensing (QS) system of bacteria helps them to communicate with each other in a density-dependent manner and regulates pathogenicity. The concentrations of autoinducers, peptides, and signaling factors are required for determining the expression of virulence factors in many pathogens. The QS signals of the pathogen are regulated by the signal transduction pathway. The binding of signal molecules to its cognate receptor brings changes in the structure of the receptor, makes it more accessible to the DNA, and thus regulates diverse expression patterns, including virulence factors. Degrading the autoinducer molecules or disturbing the quorum sensing network could be exploited to control the virulence of the pathogen while avoiding multidrug-resistant phenotypes. The rhizosphere is a tremendous source of beneficial microbes that has not yet been explored properly for its anti-quorum sensing potential. Lelliottia amnigena causes soft rot diseases in onion, potato, and other species. The present investigation was carried out with the aim of isolating the anti-quorum sensing metabolites and elucidating their role in controlling the virulence factors of the pathogen by performing a maceration assay. The ethyl acetate extracts of various bacteria are promising for violacein inhibition assay using Chromobacterium violaceum MTCC2656 and pyocyanin inhibition of Pseudomonas aeruginosa MTCC2297. Therefore, the extract was used to deduce its role in attenuation of soft rot in potato, carrot, and cucumber. The maximum reduction of macerated tissue in carrot, potato, and cucumber was given by Bacillus cereus RC1 at 91.22, 97.59, and 88.78%, respectively. The concentration-dependent inhibition of virulence traits was observed during the entire experiment. The quorum quenching potential of the bacterial extract was used to understand the regulatory metabolites. The data of the diffusible zone and gas chromatography-mass spectrometry (GC-MS) analysis showed that diketopiperazines, viz. Cyclo(d-phenylalanyl-l-prolyl), Cyclo Phe-Val, Cyclo(Pro-Ala), Cyclo(l-prolyl-l-valine), Cyclo (Leu-Leu), and Cyclo(-Leu-Pro), are prominent metabolites that could modulate the pathogenicity in L. amnigena RCE. The interaction of bacterial extracts regulates various metabolites of the pathogens during their growth in liquid culture compared to their control counterparts. This study might help in exploiting the metabolites from bacteria to control the pathogens, with concurrent reduction in the pathogenicity of the pathogens without developing antibiotic resistance.

In Vitro Efficacy for Chlorpyrifos Degradation by Novel Isolate Tistrella sp. AUC10 Isolated from Chlorpyrifos Contaminated Field.

Chlorpyrifos, an organophosphate (OP) pesticide, possess broad-spectrum insecticidal activity against Lepidoptera, Diptera, Homoptera, Coleoptera, Orthoptera, Hymenoptera, and Hemiptera. Organophosphate pesticides have acute neurotoxicity because they suppress acetylcholine esterase (AChE) which regulates the enzyme of neurotransmitters by reducing acetylcholine concentration at synaptic junctions. On exposure to OP, AChE is inactivated and leads to accumulation of acetylcholine in the junction. Moreover, due to their persistence nature they biomagnify at different food chain levels. In the present study, a newly isolated indigenous bacterial strain Tistrella sp. AUC10 was exploited for its ability to degrade chlorpyrifos pesticide. The isolate completely degrades (99.86%) chlorpyrifos. The degraded metabolites of chlorpyrifos by Tistrella sp. AUC10 were identified by GC-MS analysis. Based on the GC-MS analysis, a putative pathway of degradation of chlorpyrifos by Tistrella sp. AUC10 has been proposed. It emulsified various hydrocarbons and also confirms biosurfactant production on CTAB agar. This study is the first report on elucidation of the mechanism of degradation of chlorpyrifos by Tistrella sp. Furthermore, phytotoxicity studies of the parent compound and the biodegraded chlorpyrifos products revealed drastic reduction in the toxicity of metabolites as compared to the parent chlorpyrifos. This implies that the biodegraded metabolites of chlorpyrifos are of non-toxic nature. This study thus indicates the efficacy of Tistrella sp. AUC10 for the treatment of chlorpyrifos contaminated agricultural fields.