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Weeds cause significant agricultural losses worldwide, and herbicides have traditionally been the main solution to this problem. However, the extensive use of herbicides has led to multiple cases of weed resistance, which could generate an increase in the application concentration and consequently a higher persistence in the environment, hindering natural degradation processes. Consequently, more environmentally friendly alternatives, such as microbial bioherbicides, have been sought. Although these bioherbicides are promising, their efficacy remains a challenge, as evidenced by their limited commercial and industrial production. This article reviews the current status of microbial-based bioherbicides and highlights the potential of cell-free metabolites to improve their efficacy and commercial attractiveness. Stirred tank bioreactors are identified as the most widely used for production-scale submerged fermentation. In addition, the use of alternative carbon and nitrogen sources, such as industrial waste, supports the circular economy. Furthermore, this article discusses the optimization of downstream processes using bioprospecting and in silico technologies to identify target metabolites, which leads to more precise and efficient production strategies. Bacterial bioherbicides, particularly those derived from Pseudomonas and Xanthomonas, and fungal bioherbicides from genera such as Alternaria, Colletotrichum, Trichoderma and Phoma, show significant potential. Nevertheless, limitations such as their restricted range of action, their persistence in the environment, and regulatory issues restrict their commercial availability. The utilization of cell-free microbial metabolites is proposed as a promising solution due to their simpler handling and application. In addition, modern technologies, including encapsulation and integrated management with chemical herbicides, are investigated to enhance the efficacy and sustainability of bioherbicides.
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PURPOSE: Data on short courses of antibiotic therapy for Enterobacterales bacteremia in high-risk neutropenic patients are limited. The aim of the study was to describe and compare the frequency of bacteremia relapse, 30-day overall and infection-related mortality, Clostridiodes difficile infection and length of hospital stay since bacteremia among those who received antibiotic therapy for 7 or 14 days. METHODS: This is a multicenter, prospective, observational cohort study in adult high-risk neutropenic patients with hematologic malignancies or hematopoietic stem cell transplant and monomicrobial Enterobacterales bacteremia. They received appropriate empirical antibiotic therapy, had a clinical response within 7 days, and infection source control. Clinical, epidemiological and outcomes variables were compared based on 7 or 14 days of AT. RESULTS: Two hundred patients were included (100, 7-day antibiotic therapy; 100, 14-day antibiotic therapy). Escherichia coli was the pathogen most frequently isolated (47.5%), followed by Klebsiella sp. (40.5%). Among those patients that received 7-day vs. 14-day antibiotic course, a clinical source of bacteremia was found in 54% vs. 57% (p = 0.66), multidrug-resistant Enterobacterales isolates in 28% vs. 30% (p = 0.75), and 40% vs. 47% (p = 0.31) received combined empirical antibiotic therapy. Overall mortality was 3% vs. 1% (p = 0.62), in no case related to infection; bacteremia relapse was 7% vs. 2% (p = 0.17), and length of hospital stay since bacteremia had a median of 9 days (IQR: 7-15) vs. 14 days (IQR: 13-22) (p = < 0.001). CONCLUSIONS: These data suggest that seven-day antibiotic therapy might be adequate for patients with high-risk neutropenia and Enterobacterales bacteremia, who receive appropriate empirical therapy, with clinical response and infection source control.
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Antibacterianos , Bacteriemia , Infecções por Enterobacteriaceae , Neutropenia , Humanos , Bacteriemia/tratamento farmacológico , Bacteriemia/microbiologia , Bacteriemia/mortalidade , Antibacterianos/uso terapêutico , Antibacterianos/administração & dosagem , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Prospectivos , Neutropenia/complicações , Infecções por Enterobacteriaceae/tratamento farmacológico , Infecções por Enterobacteriaceae/mortalidade , Infecções por Enterobacteriaceae/microbiologia , Adulto , Idoso , Enterobacteriaceae/efeitos dos fármacos , Resultado do Tratamento , Tempo de Internação , Neoplasias Hematológicas/complicações , Adulto JovemRESUMO
Background: Cytomegalovirus (CMV) infection remains the most common clinically significant infection after allogeneic hematopoietic stem cell transplantation (allo-HCT) and is associated with considerable morbidity and mortality. Objectives: The present study was designed to describe and compare the incidence of untreated CMV reactivation (uCMVr), clinically significant infection (cs-CMVi) and disease (CMVd), as well as CMV-related hospitalization and outcome of allo-HCT patients, either treated with letermovir (LET) primary prophylaxis or managed with preemptive therapy (PET). Methods: This is a prospective observational cohort study of adult CMV seropositive allo-HCT patients who either received primary prophylaxis with LET within the first 100 days after HCT or were managed with PET. Results: The study population comprised 105 patients (28 in the LET group and 77 in the PET group). Compared to the PET group, patients in the LET group received more allo-HCT from alternative donors (54.5% vs. 82.14%, P=0.012). More than half of the patients in both groups were classified as high risk for CMVd. In the LET vs. PET group, cs-CMVi and CMVd developed respectively in 0 vs. 50 (64.94%), P=<0.0001, and 0 vs. 6 (7.79%), P=0.18. In the LET group, uCMVr occurred in 5 (17.8%) and were all considered blips. Hospital admissions related to cs-CMVi or CMVd in the PET group vs. LET group were 47 (61.04%) vs. 0, respectively, P=<0.0001. No differences were observed in 100-day mortality. Conclusions: LET primary prophylaxis proved effective in preventing cs-CMVi and CMVd and reducing hospitalizations in allo-HCT adults. Blips can occur during prophylaxis and do not require LET discontinuation.
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Background/Introduction: Adipose tissue (AT) has been highlighted as a promising reservoir of infection for viruses, bacteria and parasites. Among them is Trypanosoma cruzi, which causes Chagas disease. The recommended treatment for the disease in Brazil is Benznidazole (BZ). However, its efficacy may vary according to the stage of the disease, geographical origin, age, immune background of the host and sensitivity of the strains to the drug. In this context, AT may act as an ally for the parasite survival and persistence in the host and a barrier for BZ action. Therefore, we investigated the immunomodulation of T. cruzi-infected human AT in the presence of peripheral blood mononuclear cells (PBMC) where BZ treatment was added. Methods: We performed indirect cultivation between T. cruzi-infected adipocytes, PBMC and the addition of BZ. After 72h of treatment, the supernatant was collected for cytokine, chemokine and adipokine assay. Infected adipocytes were removed to quantify T. cruzi DNA, and PBMC were removed for immunophenotyping. Results: Our findings showed elevated secretion of interleukin (IL)-6, IL-2 and monocyte chemoattractant protein-1 (MCP-1/CCL2) in the AT+PBMC condition compared to the other controls. In contrast, there was a decrease in tumor necrosis factor (TNF) and IL-8/CXCL-8 in the groups with AT. We also found high adipsin secretion in PBMC+AT+T compared to the treated condition (PBMC+AT+T+BZ). Likewise, the expression of CD80+ and HLA-DR+ in CD14+ cells decreased in the presence of T. cruzi. Discussion: Thus, our findings indicate that AT promotes up-regulation of inflammatory products such as IL-6, IL-2, and MCP-1/CCL2. However, adipogenic inducers may have triggered the downregulation of TNF and IL-8/CXCL8 through the peroxisome proliferator agonist gamma (PPAR-g) or receptor expression. On the other hand, the administration of BZ only managed to reduce inflammation in the microenvironment by decreasing adipsin in the infected culture conditions. Therefore, given the findings, we can see that AT is an ally of the parasite in evading the host's immune response and the pharmacological action of BZ.
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Doença de Chagas , Nitroimidazóis , Trypanosoma cruzi , Humanos , Interleucina-8 , Leucócitos Mononucleares , Fator D do Complemento , Interleucina-2/uso terapêutico , Tecido Adiposo , Adipócitos , Fator de Necrose Tumoral alfa/uso terapêutico , Imunidade , Falha de TratamentoRESUMO
Studies involving the immune response in Chagas disease suggest an imbalance in the immune response of symptomatic patients, with an inflammatory profile dominating in Chagas heart disease, mainly by tumour necrosis factor (TNF). TNF is considered a key cytokine in immunopathology in chronic carriers in several processes during the immune response. Our work aimed to evaluate regulatory (interleukin [IL]-4 and IL-10) and inflammatory (TNF, interferon-gamma [IFN-γ], IL-2 and IL-6) cytokines in peripheral blood mononuclear cells culture supernatants. of affected patients with undetermined clinical forms-IND (n = 13) mild heart form-CARD1 (n = 13) and severe cardiac form-CARD2 (n = 16), treated in vitro with two TNF blockers, Adalimumab (ADA) and Etanercept (ETA) alone or in association with Benznidazole (BZ). The results indicate that ADA was more competent in blocking TNF (compared to ETA) in all groups but with much lower levels in the CARD2 group. ETA statistically decreased TNF levels only in the CARD2 group. IFN-γ increased in the CARD2 group after treatment with ETA relative to ADA. IL-4 had its levels decreased when treated by both drugs. IL-2 was detected in cells from CARD2 carriers compared to the NEG group after treatment with both drugs. The association with BZ decreased levels of IL-2/TNF and increased IL-4. These data reinforce the participation of TNF in severe Chagas heart disease and bring perspectives on using these blockers in the immunological treatment of Chagas disease since the use of BZ is extremely limited in these patients.
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Doença de Chagas , Cardiopatias , Nitroimidazóis , Humanos , Doença de Chagas/tratamento farmacológico , Citocinas , Cardiopatias/tratamento farmacológico , Cardiopatias/parasitologia , Interferon gama , Interleucina-2 , Interleucina-4 , Leucócitos Mononucleares , Inibidores do Fator de Necrose Tumoral/uso terapêutico , Fator de Necrose Tumoral alfaRESUMO
Few studies have evaluated the efficacy of ceftazidime-avibactam (CA) for Klebsiella pneumoniae carbapenemase-producing Enterobacterales bacteremia (KPC-PEB) in high-risk neutropenic patients. This is a prospective multicenter observational study in high-risk neutropenic patients with multi-drug resistant Enterobacterales bacteremia. They were compared according to the resistance mechanism and definitive treatment provided: KPC-CPE treated with CA (G1), KPC-CPE treated with other antibiotics (G2), and patients with ESBL-producing Enterobacterales bacteremia who received appropriate definitive therapy (G3). Thirty-day mortality was evaluated using a logistic regression model, and survival was analyzed with Kaplan-Meier curves. A total of 238 patients were included: 18 (G1), 52 (G2), and 168 (G3). Klebsiella spp. (60.9%) and Escherichia coli (26.4%) were the Enterobacterales most frequently isolated, and 71% of the bacteremias had a clinical source. The resistance profile between G1 and G2 was colistin 35.3% vs. 36.5%, amikacin 16.7% vs. 40.4%, and tigeclycline 11.1% vs. 19.2%. The antibiotics prescribed in combination with G2 were carbapenems, colistin, amikacin, fosfomycin, tigecycline, and fluoroquinolones. Seven-day clinical response in G1 vs. G2 vs. G3 was 94.4% vs. 42.3% vs. 82.7%, respectively (p < 0.001). Thirty-day overall mortality in G1 vs. G2 vs. G3 was 22.2% vs. 53.8% vs. 11.9%, respectively (p < 0.001), and infection-related mortality was 5.5% vs. 51.9% vs. 7.7% (p < 0.001). The independent risk factors for mortality were Pitt score > 4: OR 3.63, 95% CI, 1.18-11.14 (p = 0.025) and KPC-PEB treated with other antibiotics: OR 8.85, 95% CI, 2.58-30.33 (p = 0.001), while 7-day clinical response was a protective factor for survival: OR 0.02, 95% CI, 0.01-0.08 (p < 0.001). High-risk neutropenic patients with KPC-CPE treated with CA had an outcome similar to those treated for ESBL-producing Enterobacterales, with higher 7-day clinical response and lower overall and infection-related mortality than those treated with other antibiotics. In view of these data, CA may be considered the preferred therapeutic option for KPC-PEB in high-risk neutropenic patients.
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INTRODUCCIÓN: Las infecciones fúngicas invasoras (IFI) en pacientes con neoplasias hematológicas (NH) representan un desafío diagnóstico y terapéutico. OBJETIVOS: Describir la etiología, características clínicas, diagnóstico y evolución de los episodios de IFI probadas y probables en pacientes con NH y trasplante de progenitores hematopoyéticos (TPH). PACIENTES Y MÉTODOS: Estudio descriptivo, retrospectivo y de cohorte que incluyó IFI probadas y probables en pacientes adultos con NH y TPH. Se realizó seguimiento hasta el día 90. RESULTADOS: Se incluyeron 80 episodios de IFI: 49% probadas y 51% probables, 67,5% por hongos filamentosos (HF), 30% por hongos levaduriformes (HL) y 2,5% por hongos dimorfos. Los tipos de IFI más frecuentes fueron aspergilosis invasoras pulmonares (AP) y candidiasis invasoras (CI), en su mayoría por Candida spp. no albicans. Todos los casos de AP se diagnosticaron por detección de galactomanano en sangre y/o lavado broncoalveolar, y solamente 22,2% presentaban nódulos con halo en la tomografía computada (TC) de tórax, siendo los infiltrados inespecíficos los hallazgos más frecuentes. Tuvieron coinfección bacteriana y viral el 30 y 17,5%, respectivamente. El 50% fueron IFI de brecha, y la mortalidad global y mortalidad relacionada a la IFI fue 51 y 24%, respectivamente. CONCLUSIÓN: Los HF fueron la principal causa de IFI, con una gran proporción de IFI de brecha, y presentaron elevada mortalidad. Para el diagnóstico, resulta importante la utilización de biomarcadores y jerarquizar cualquier imagen patológica en la TC.
BACKGROUND: Invasive fungal infections (IFI) in patients with hematological malignancies (HM) represent a diagnostic and therapeutic challenge. AIM: To describe the etiology, clinical characteristics, diagnosis and evolution of proven and probable IFI episodes in patients with HM and hematopoietic stem cell transplantation (HSCT). METHODS: Retrospective, descriptive, cohort study performed in adult patients with HM and HSCT, who developed proven and probable IFI. Follow-up was carried out until day 90. RESULTS: A total of 80 IFI episodes were included: 49% proven and 51% probable, 67,5% due to mold (M), 30% to yeast-like fungi (Y) and 2,5% to dimorphic fungi. The most frequent causes were probable pulmonary aspergillosis (PA) and invasive candidiasis (IC), mainly due to non-albicans Candida species. PA were all diagnosed by detection of galactomannan (GM) in blood and bronchoalveolar lavage, and only 22,2% presented halo sign on chest CT. Bacterial and viral coinfections were reported in 30% and 17,5% respectively. Breakthrough IFI occurred in 50%, and global and IFI-related mortality were 51% and 24% respectively. CONCLUSION: Mold was the main cause of IFI, with a large proportion of breakthrough IFI, presenting high mortality. The use of biomarkers and the classification of any pathological image on CT contribute to the diagnosis.
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Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Neoplasias Hematológicas/complicações , Infecções Fúngicas Invasivas/diagnóstico , Infecções Fúngicas Invasivas/etiologia , Argentina , Evolução Clínica , Estudos Retrospectivos , Fatores de Risco , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Neoplasias Hematológicas/mortalidade , Infecções Fúngicas Invasivas/mortalidade , Infecções Fúngicas Invasivas/tratamento farmacológico , Hospitais Universitários , Antifúngicos/uso terapêuticoRESUMO
INTRODUCCIÓN: Las bacteriemias por Enterobacterales productores de carbapenemasa KPC (EPC-KPC) presentan una mortalidad elevada y opciones terapéuticas limitadas. OBJETIVOS: Describir y comparar la evolución de los pacientes con bacteriemia por EPC-KPC tratados con ceftazidima/avibactam (CA) frente a otros antimicrobianos (OA). PACIENTES Y MÉTODOS: Estudio prospectivo y retrospectivo de casos y controles. Se incluyeron pacientes adultos con bacteriemia por EPC-KPC, con una proporción entre casos tratados con CA y controles tratados con OA. de 1:2. Se analizaron variables clínicas, epidemiológicas y de evolución. RESULTADOS: Se incluyeron 48 pacientes (16 CA y 32 OA). Los casos se encontraban más frecuentemente neutropénicos (50 vs.16%, p = 0,012); asimismo, presentaron medianas de score de APACHE II más altas y de score de Pitt más bajas. El 65% de la cohorte total presentó un foco clínico y Klebsiellapneumoniae fue el microorganismo más frecuentemente aislado. Los casos recibieron una mayor proporción de tratamiento antimicrobiano empírico adecuado (81 vs. 53%, p = 0,05). La antibioterapia dirigida en casos y controles fue combinada en 38 y 91%, p = 0,009. Los casos presentaron menor mortalidad al día 7 y al día 30 relacionada a infección (0 vs. 22%, p = 0,04 y 0 vs. 34%, p = 0,008). Solo los controles desarrollaron shock, ingresaron a la unidad de cuidados intensivos y presentaron bacteriemia de brecha. CONCLUSIÓN: CA mostró beneficio clínico frente a OA para el tratamiento de pacientes con bacteriemia por EPC-KPC.
BACKGROUND: KPC-producing Enterobacterales bacteremia (KPCCPE) is associated with a high mortality rate and limited therapeutic options. AIM: To describe and compare the outcome of patients with KPC-CPE bacteremia treated with ceftazidime/avibactam (CA) versus other antibiotics (OA). METHODS: Prospective and retrospective cases and control study performed in adult patients with KPC-CPE bacteremia, with a 1:2 ratio between cases treated with CA. and controls treated with OA. Clinical, epidemiological, and outcome variables were analyzed. RESULTS: Forty-eight patients (16 CA and 32 OA) were included. Cases were more frequently neutropenic (50 vs. 16%, p = 0.012), presented higher median APACHE II score and lower Pitt score. Of the total cohort, 65% had a clinical source, and Klebsiella pneumoniae was the most frequently isolated microorganism. Cases received more adequate empirical antibiotic treatment (81 vs. 53%, p = 0.05). Targeted antibiotic therapy in cases and controls was combined in 38 and 91%, p = 0.009. Cases had a lower 7-day mortality and 30-day infection-related mortality (0 vs. 22%, p = 0.04 and 0 vs. 34%, p = 0.008). Only controls developed shock, were admitted to the intensive care unit, and had breakthrough bacteremia. CONCLUSION: CA. showed clinical benefit over OA in the treatment of patients with EPC-KPC bacteremia.
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Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Ceftazidima/uso terapêutico , Bacteriemia/tratamento farmacológico , Infecções por Enterobacteriaceae/tratamento farmacológico , Compostos Azabicíclicos/uso terapêutico , Antibacterianos/uso terapêutico , Proteínas de Bactérias , beta-Lactamases , Estudos de Casos e Controles , Ceftazidima/administração & dosagem , Evolução Clínica , Estudos Prospectivos , Bacteriemia/microbiologia , Bacteriemia/mortalidade , Combinação de Medicamentos , Enterobacteriaceae/isolamento & purificação , Enterobacteriaceae/efeitos dos fármacos , Infecções por Enterobacteriaceae/mortalidade , Compostos Azabicíclicos/administração & dosagem , Inibidores de beta-Lactamases , Antibacterianos/administração & dosagemRESUMO
Immobilization of enzymes is one of the protein engineering methods used to improve their thermal and long-term stabilities. Immobilized pectinase has become an essential biocatalyst for optimization in the food processing industry. Herein, nanostructured magnetic nanoparticles were prepared in situ for use as supports to immobilize pectinase. The structural, morphological, optical and magnetic features and the chemical compositions of the nanoparticles were characterized. Nanoparticle agglomeration and low porosity were observed due to the synthetic conditions. These nanoparticles exhibited superparamagnetic behavior, which is desirable for biotechnological applications. The maximum retention rate for the enzyme was observed at pH 4.5 with a value of 1179.3 U/mgNP (units per milligram of nanoparticle), which was equivalent to a 65.6% efficiency. The free and immobilized pectinase were affected by the pH and temperature. The long-term instability caused 40% and 32% decreases in the specific activities of the free and immobilized pectinase, respectively. The effects of immobilization were analyzed with kinetic and thermodynamic studies. These results indicated a significant affinity for the substrate, a decreased reaction rate, and improved thermal stability of the immobilized pectinase. The reusability of the immobilized pectinase was preserved effectively during cycling, with only a 21.2% decrease in activity observed from the first to the last use. Therefore, alternative magnetic nanoparticles are presented for immobilizing and maintaining the thermostability of pectinase.
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INTRODUCCIÓN: La infección por citomegalovirus (CMV) sigue siendo la infección con relevancia clínica más frecuente luego del trasplante alogénico de progenitores hematopoyéticos (TPHa), presentando alta morbilidad y mortalidad. Por este motivo, es importante implementar estrategias de prevención para reducir la frecuencia de la infección por CMV. OBJETIVO: Describir la frecuencia de infección, infección clínicamente significativa (ICS) y enfermedad por CMV en pacientes seropositivos que recibieron un TPHa y profilaxis primaria con letermovir. PACIENTES Y MÉTODOS: Estudio descriptivo de cohorte longitudinal, en pacientes con TPHa seropositivos para CMV que recibieron profilaxis primaria con letermovir hasta el día 100 posTPH. RESULTADOS: Se incluyeron 25 pacientes adultos con una mediana de edad de 41 años, el 44% fue de donante no relacionado y 36% de donante haploidéntico. Ochenta por ciento tenía tres o más factores de riesgo para infección por CMV y a 52% se le estratificó como de alto riesgo para enfermedad por CMV. La profilaxis con letermovir tuvo una mediana de duración de 97 días. Durante los 100 días pos-TPH, 20% de los pacientes presentaron infección por CMV, con carga viral plasmática detectable no cuantificable, que se negativizó en el siguiente control semanal sin discontinuación del letermovir. Ningún paciente presentó ICS ni enfermedad por CMV durante este período. CONCLUSIÓN: La profilaxis con letermovir fue efectiva para prevenir la ICS y la enfermedad por CMV.
BACKGROUND: Cytomegalovirus (CMV) infection remains the most common clinically significant infection after allogeneic stem cell transplantation (aSCT), with a high morbidity and mortality rate. In order to reduce its frequency, prevention strategies should be implemented. AIM: To describe the frequency of infection, clinically significant infection (CSI) and CMV disease in seropositive patients who received aSCT and primary prophylaxis with letermovir. METHODS: Longitudinal descriptive cohort study in seropositive patients who received aSCT and primary prophylaxis with letermovir until day 100 post-SCT. RESULTS: Twenty-five adult patients with a median age of 41 years were included; 44% were unrelated donors, and 36% were haploidentical donors. Eighty percent had three or more risk factors for CMV infection, and 52% were stratified as high risk for CMV disease. Letermovir prophylaxis had a median duration of 97 days. Twenty percent of the patients developed CMV infection through day 100 post-SCT, with detectable non-quantifiable CMV viral load in plasma. This became negative in the following weekly control without discontinuation of letermovir. No patient developed CSI or CMV organ disease during this period. CONCLUSION: Letermovir prophylaxis proved to be effective in preventing CSI and CMV disease.