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1.
Int J Biol Sci ; 20(5): 1634-1651, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38481819

RESUMO

Background: Hypoxia induces hepatocellular carcinoma (HCC) malignancies; yet it also offers treatment opportunities, exemplified by developing hypoxia-activated prodrugs (HAPs). Although HAP TH-302 combined with therapeutic antibody (Ab) has synergistic effects, the clinical benefits are limited by the on-target off-tumor toxicity of Ab. Here, we sought to develop a hypoxia-activated anti-M2 splice isoform of pyruvate kinase (PKM2) Ab combined with TH-302 for potentiated targeting therapy. Methods: Codon-optimized and hypoxia-activation strategies were used to develop H103 Ab-azo-PEG5k (HAP103) Ab. Hypoxia-activated HAP103 Ab was characterized, and hypoxia-dependent antitumor and immune activities were evaluated. Selective imaging and targeting therapy with HAP103 Ab were assessed in HCC-xenografted mouse models. Targeting selectivity, systemic toxicity, and synergistic therapeutic efficacy of HAP103 Ab with TH-302 were evaluated. Results: Human full-length H103 Ab was produced in a large-scale bioreactor. Azobenzene (azo)-linked PEG5k conjugation endowed HAP103 Ab with hypoxia-activated targeting features. Conditional HAP103 Ab effectively inhibited HCC cell growth, enhanced apoptosis, and induced antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) functions. Analysis of HCC-xenografted mouse models showed that HAP103 Ab selectively targeted hypoxic HCC tissues and induced potent tumor-inhibitory activity either alone or in combination with TH-302. Besides the synergistic effects, HAP103 Ab had negligible side effects when compared to parent H103 Ab. Conclusion: The hypoxia-activated anti-PKM2 Ab safely confers a strong inhibitory effect on HCC with improved selectivity. This provides a promising strategy to overcome the on-target off-tumor toxicity of Ab therapeutics; and highlights an advanced approach to precisely kill HCC in combination with HAP TH-302.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Nitroimidazóis , Mostardas de Fosforamida , Pró-Fármacos , Humanos , Animais , Camundongos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Pró-Fármacos/uso terapêutico , Pró-Fármacos/farmacologia , Hipóxia Celular/fisiologia , Linhagem Celular Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto , Hipóxia
2.
Phys Chem Chem Phys ; 26(11): 8879-8890, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38426309

RESUMO

Radiation therapy uses ionizing radiation to break chemical bonds in cancer cells, thereby causing DNA damage and leading to cell death. The therapeutic effectiveness can be further increased by making the tumor cells more sensitive to radiation. Here, we investigate the role of the initial halogen atom core hole on the photofragmentation dynamics of 2-bromo-5-iodo-4-nitroimidazole, a potential bifunctional radiosensitizer. Bromine and iodine atoms were included in the molecule to increase the photoionization cross-section of the radiosensitizer at higher photon energies. The fragmentation dynamics of the molecule was studied experimentally in the gas phase using photoelectron-photoion-photoion coincidence spectroscopy and computationally using Born-Oppenheimer molecular dynamics. We observed significant changes between shallow core (I 4d, Br 3d) and deep core (I 3d) ionization in fragment formation and their kinetic energies. Despite the fact, that the ions ejected after deep core ionization have higher kinetic energies, we show that in a cellular environment, the ion spread is not much larger, keeping the damage well-localized.


Assuntos
Iodo , Nitroimidazóis , Raios Ultravioleta , Fótons , Radiação Ionizante
3.
BMJ Open Diabetes Res Care ; 12(2)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38453236

RESUMO

INTRODUCTION: Colonocyte oxidation of bacterial-derived butyrate has been reported to maintain synergistic obligate anaerobe populations by reducing colonocyte oxygen levels; however, it is not known whether this process is disrupted during the progression of type 2 diabetes. Our aim was to determine whether diabetes influences colonocyte oxygen levels in the University of California Davis type 2 diabetes mellitus (UCD-T2DM) rat model. RESEARCH DESIGN AND METHODS: Age-matched male UCD-T2DM rats (174±4 days) prior to the onset of diabetes (PD, n=15), within 1 month post-onset (RD, n=12), and 3 months post-onset (D3M, n=12) were included in this study. Rats were administered an intraperitoneal injection of pimonidazole (60 mg/kg body weight) 1 hour prior to euthanasia and tissue collection to estimate colonic oxygen levels. Colon tissue was fixed in 10% formalin, embedded in paraffin, and processed for immunohistochemical detection of pimonidazole. The colonic microbiome was assessed by 16S gene rRNA amplicon sequencing and content of short-chain fatty acids was measured by liquid chromatography-mass spectrometry. RESULTS: HbA1c % increased linearly across the PD (5.9±0.1), RD (7.6±0.4), and D3M (11.5±0.6) groups, confirming the progression of diabetes in this cohort. D3M rats had a 2.5% increase in known facultative anaerobes, Escherichia-Shigella, and Streptococcus (false discovery rate <0.05) genera in colon contents. The intensity of pimonidazole staining of colonic epithelia did not differ across groups (p=0.37). Colon content concentrations of acetate and propionate also did not differ across UCD-T2DM groups; however, colonic butyric acid levels were higher in D3M rats relative to PD rats (p<0.01). CONCLUSIONS: The advancement of diabetes in UCD-T2DM rats was associated with an increase in facultative anaerobes; however, this was not explained by changes in colonocyte oxygen levels. The mechanisms underlying shifts in gut microbe populations associated with the progression of diabetes in the UCD-T2DM rat model remain to be identified.


Assuntos
Diabetes Mellitus Tipo 2 , Nitroimidazóis , Humanos , Ratos , Masculino , Animais , Recém-Nascido , Hipóxia , Oxigênio
4.
Bioorg Med Chem ; 102: 117679, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38461555

RESUMO

Trichomoniasis, a prevalent sexually transmitted infection (STI) caused by the protozoan Trichomonas vaginalis, has gained increased significance globally. Its relevance has grown in recent years due to its association with a heightened risk of acquiring and transmitting the human immunodeficiency virus (HIV) and other STIs. In addition, many publications have revealed a potential link between trichomoniasis and certain cancers. Metronidazole (MTZ), a nitroimidazole compound developed over 50 years ago, remains the first-choice drug for treatment. However, reports of genotoxicity and side effects underscore the necessity for new compounds to address this pressing global health concern. In this study, we synthesized ten pyrazole-nitroimidazoles 1(a-j) and 4-nitro-1-(hydroxyethyl)-1H-imidazole 2, an analog of metronidazole (MTZ), and assessed their trichomonacidal and cytotoxic effects. All compounds 1(a-j) and 2 exhibited IC50 values ≤ 20 µM and ≤ 41 µM, after 24 h and 48 h, respectively. Compounds 1d (IC50 5.3 µM), 1e (IC50 4.8 µM), and 1i (IC50 5.2 µM) exhibited potencies equivalent to MTZ (IC50 4.9 µM), the reference drug, after 24 h. Notably, compound 1i showed high anti-trichomonas activity after 24 h (IC50 5.2 µM) and 48 h (IC50 2.1 µM). Additionally, all compounds demonstrated either non-cytotoxic to HeLa cells (CC50 > 100 µM) or low cytotoxicity (CC50 between 69 and 100 µM). These findings suggest that pyrazole-nitroimidazole derivatives represent a promising heterocyclic system, serving as a potential lead for further optimization in trichomoniasis chemotherapy.


Assuntos
Antiprotozoários , Nitroimidazóis , Tricomoníase , Trichomonas vaginalis , Humanos , Nitroimidazóis/farmacologia , Metronidazol/farmacologia , Células HeLa , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Tricomoníase/tratamento farmacológico , Pirazóis/farmacologia , Pirazóis/uso terapêutico
5.
Nucl Med Biol ; 130-131: 108891, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38458074

RESUMO

Alzheimer's disease (AD) and non-AD tauopathies such as chronic traumatic encephalopathy (CTE), progressive supranuclear palsy (PSP), and corticobasal degeneration (CBD) are characterized by the abnormal aggregation of three-repeat (3R) and/or four-repeat (4R) tau isoforms. Several tau-PET tracers have been applied for human imaging of AD and non-AD tauopathies including [18F]PI-2620. Our objective is to evaluate [3H]PI-2620 and two promising structural derivatives, [3H]PI-2014 and [3H]F-4, using in vitro saturation assays and competitive binding assays against new chemical entities based on this scaffold in human AD tissues for comparison with PSP, CBD and CTE tissues. Thin section autoradiography was employed to assess specific binding and distribution of [3H]PI-2620 and [3H]F-4 in fresh-frozen human post-mortem AD, PSP, CBD and CTE tissues. Immunohistochemistry was performed for phospho-tau (AT8) and 4R-tau (RD4). Homogenate filtration binding assays were performed for saturation analysis and competitive binding studies against [3H]PI-2620. All compounds bound with high affinity in AD tissue. In PSP tissue [3H]PI-2620 demonstrated the highest affinity (5.3 nM) and in CBD tissue [3H]F-4 bound with the highest affinity (9.4 nM). Over 40 fluorinated derivatives based on PI-2620 and F-4 were screened in AD and PSP tissue. Notably, compound 2 was the most potent derivative in PSP tissue (Ki = 7.3 nM). By autoradiography, [3H]PI-2620 and [3H]F-4 demonstrated positive signals similar in intensity in AD, PSP and CTE tissues that were displaced by homologous blockade. Binding of both radiotracers aligned with immunostaining for 4R-tau. This work demonstrates that [3H]PI-2620 and [3H]F-4 show promise for imaging 4R-tau aggregates in non-AD tauopathies. PI-2620 continues to serve as a structural scaffold for PET radiotracers with higher affinity for non-AD tau over AD tau.


Assuntos
Doença de Alzheimer , Nitroimidazóis , Piridinas , Tauopatias , Humanos , Proteínas tau/metabolismo , Tauopatias/diagnóstico por imagem , Tauopatias/metabolismo , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Encéfalo/metabolismo
6.
Ugeskr Laeger ; 186(10)2024 Mar 04.
Artigo em Dinamarquês | MEDLINE | ID: mdl-38445341

RESUMO

The number of patients with drug-resistant tuberculosis (DR-TB) is increasing worldwide. This review summarises the global epidemiology of DR-TB and current treatment challenges. Luckily, novel regimens comprising bedaquiline, pretomanid, linezolid, and moxifloxacin have seemingly mitigated the global threat posed by DR-TB. However, emerging resistance against bedaquiline and pretomanid, among other factors, persists as ongoing concerns in the global fight against DR-TB. While the new regimens are groundbreaking, the sustained development of novel drugs targeting the most resistant forms of tuberculosis is of utmost importance for future efforts against DR-TB.


Assuntos
Nitroimidazóis , Tuberculose Resistente a Múltiplos Medicamentos , Humanos , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Linezolida
7.
Artigo em Inglês | MEDLINE | ID: mdl-38324876

RESUMO

Multiple myeloma (MM) associated with Chagas disease is rarely described. This disease and its therapy suppress T cell and macrophage functions and increase regulatory T cell function, allowing the increase of parasitemia and the risk of Chagas Disease Reactivation (CDR). We aimed to analyze the role of conventional (cPCR) and quantitative Polymerase Chain Reaction (qPCR) for prospective monitoring of T. cruzi parasitemia, searching for markers of preemptive antiparasitic therapy in MM patients with Chagas disease. Moreover, we investigated the incidence and management of hematological diseases and CDR both inside and outside the transplant setting in the MEDLINE database. We found 293 studies and included 31 of them. Around 1.9-2.0% of patients with Chagas disease were reported in patients undergoing Stem Cell Transplantation. One case of CDR was described in eight cases of MM and Chagas disease. We monitored nine MM and Chagas disease patients, seven under Autologous Stem Cell Transplantation (ASCT), during 44.56±32.10 months (mean±SD) using parasitological methods, cPCR, and qPCR. From these patients, three had parasitemia. In the first, up to 256 par Eq/mL were detected, starting from 28 months after ASCT. The second patient dropped out and died soon after the detection of 161.0 par Eq/mL. The third patient had a positive blood culture. Benznidazole induced fast negativity in two cases; followed by notably lower levels in one of them. Increased T. cruzi parasitemia was related to the severity of the underlying disease. We recommend parasitemia monitoring by qPCR for early introduction of preemptive antiparasitic therapy to avoid CDR.


Assuntos
Doença de Chagas , Transplante de Células-Tronco Hematopoéticas , Mieloma Múltiplo , Nitroimidazóis , Trypanosoma cruzi , Humanos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/complicações , Antiparasitários/uso terapêutico , Parasitemia/tratamento farmacológico , Parasitemia/epidemiologia , Parasitemia/parasitologia , Estudos Prospectivos , Transplante Autólogo , Doença de Chagas/tratamento farmacológico , Doença de Chagas/epidemiologia , Nitroimidazóis/uso terapêutico
8.
Parasite Immunol ; 46(2): e13024, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38385576

RESUMO

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.


Assuntos
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 alfa
9.
PLoS Negl Trop Dis ; 18(2): e0011961, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38408095

RESUMO

BACKGROUND: Trypanosoma cruzi and HIV coinfection can evolve with depression of cellular immunity and increased parasitemia. We applied quantitative PCR (qPCR) as a marker for preemptive antiparasitic treatment to avoid fatal Chagas disease reactivation and analyzed the outcome of treated cases. METHODOLOGY: This mixed cross-sectional and longitudinal study included 171 Chagas disease patients, 60 coinfected with HIV. Of these 60 patients, ten showed Chagas disease reactivation, confirmed by parasites identified in the blood, cerebrospinal fluid, or tissues, 12 exhibited high parasitemia without reactivation, and 38 had low parasitemia and no reactivation. RESULTS: We showed, for the first time, the success of the timely introduction of benznidazole in the non-reactivated group with high levels of parasitemia detected by qPCR and the absence of parasites in reactivated cases with at least 58 days of benznidazole. All HIV+ patients with or without reactivation had a 4.0-5.1 higher chance of having parasitemia than HIV seronegative cases. A positive correlation was found between parasites and viral loads. Remarkably, treated T. cruzi/HIV-coinfected patients had 77.3% conversion from positive to negative parasitemia compared to 19.1% of untreated patients. Additionally, untreated patients showed ~13.6 times higher Odds Ratio of having positive parasitemia in the follow-up period compared with treated patients. Treated and untreated patients showed no differences regarding the evolution of Chagas disease. The main factors associated with all-cause mortality were higher parasitemia, lower CD4 counts/µL, higher viral load, and absence of antiretroviral therapy. CONCLUSION: We recommend qPCR prospective monitoring of T. cruzi parasitemia in HIV+ coinfected patients and point out the value of pre-emptive therapy for those with high parasitemia. In parallel, early antiretroviral therapy introduction is advisable, aiming at viral load control, immune response restoration, and increasing survival. We also suggest an early antiparasitic treatment for all coinfected patients, followed by effectiveness analysis alongside antiretroviral therapy.


Assuntos
Doença de Chagas , Coinfecção , Infecções por HIV , Nitroimidazóis , Trypanosoma cruzi , Humanos , Trypanosoma cruzi/genética , Parasitemia/tratamento farmacológico , Parasitemia/parasitologia , Estudos Longitudinais , Estudos Transversais , Estudos Prospectivos , Doença de Chagas/complicações , Doença de Chagas/tratamento farmacológico , Doença de Chagas/parasitologia , Nitroimidazóis/uso terapêutico , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Reação em Cadeia da Polimerase , Antiparasitários/uso terapêutico , Coinfecção/parasitologia
10.
Int J Tuberc Lung Dis ; 28(2): 81-85, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38303041

RESUMO

BACKGROUND: Recent clinical findings reported improvement in the treatment outcomes of highly resistant TB (HDR-TB) with the pretomanid (Pa) based regimen. This study aimed to evaluate the cost-effectiveness of the Pa-based regimen for HDR-TB treatment from the perspective of the healthcare sector in the United States.METHODS: A lifelong decision-analytic model was constructed to simulate potential treatment outcomes of 1) the bedaquiline-Pa-linezolid (BPaL) regimen, and 2) the bedaquiline-linezolid (B-L) based regimen in a hypothetical cohort of adult patients with HDR-TB. Primary model outputs were TB-related direct medical costs, qualityadjusted life-years (QALYs) and incremental cost per QALY gained (ICER).RESULTS: In the base-case analysis, the BPaL regimen gained 3.0054 QALYs and saved costs by USD60,433 when compared to the B-L-based regimen. In the probabilistic sensitivity analysis, the BPaL regimen gained higher QALYs at a lower cost in 80.3% of the time, and gained higher QALYs at a higher cost with ICER less than the willingness-to-pay (WTP) threshold (100,000 USD/QALY) in 19.0% of the simulations. The probability of the BPaL regimen being cost-effective was higher than the B-L-based regimen throughout the variation of WTP.CONCLUSION: BPaL therapy is likely the cost-effective option for HDR-TB treatment from the US healthcare sector perspective.


Assuntos
Nitroimidazóis , Tuberculose , Adulto , Humanos , Estados Unidos , Análise Custo-Benefício , Tuberculose/tratamento farmacológico , Linezolida , Nitroimidazóis/uso terapêutico , Anos de Vida Ajustados por Qualidade de Vida
11.
J Med Chem ; 67(4): 2264-2286, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38351709

RESUMO

Delamanid, bedaquiline, and pretomanid have been recently added in the anti-tuberculosis (anti-TB) treatment regimens and have emerged as potential solutions for combating drug-resistant TB. These drugs have proven to be effective in treating drug-resistant TB when used in combination. However, concerns have been raised about the eventual loss of these drugs due to evolving resistance mechanisms and certain adverse effects such as prolonged QT period, gastrointestinal problems, hepatotoxicity, and renal disorders. This Perspective emphasizes the properties of these first-in-class drugs, including their mechanism of action, pharmacokinetics/pharmacodynamics profiles, clinical studies, adverse events, and underlying resistance mechanisms. A brief coverage of efforts toward the generation of best-in-class leads in each class is also provided. The ongoing clinical trials of new combinations of these drugs are discussed, thus providing a better insight into the use of these drugs while designing an effective treatment regimen for resistant TB cases.


Assuntos
Diarilquinolinas , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Mycobacterium tuberculosis , Nitroimidazóis , Tuberculose Resistente a Múltiplos Medicamentos , Humanos , Antituberculosos/efeitos adversos , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Nitroimidazóis/farmacologia , Nitroimidazóis/uso terapêutico , Oxazóis/farmacologia , Oxazóis/uso terapêutico , Resistência a Medicamentos
12.
Microbiol Spectr ; 12(3): e0007024, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38334384

RESUMO

Previous work reported unprecedented differences in the intrinsic in vitro susceptibility of the Mycobacterium tuberculosis complex (MTBC) to pretomanid (Pa) using the Mycobacteria Growth Indicator Tube (MGIT) system. We tested 125 phylogenetically diverse strains from all known MTBC lineages (1-9) without known Pa resistance mutations and four strains with known resistance mutations as controls. This confirmed that MTBC, unlike most bacteria-antimicrobial combinations, displayed substantial differences in the intrinsic susceptibility relative to the technical variation of Pa MIC testing. This was also the case for the Middlebrook 7H11 (7H11) medium, demonstrating that these differences were not specific to MGIT. Notably, lineage 1 was confirmed to have intrinsically elevated MICs compared with lineages 2, 3, 4, and 7 (L2-4/7), underlining the urgent need for WHO to publish its decision of whether lineage 1 should be deemed treatable by BPaL(M), the now preferred all-oral regimen for treating rifampin-resistant tuberculosis. Lineages 5 and 6, which are most frequent in West Africa, responded differently to Pa, with lineage 5 being more similar to L2-4/7 and lineage 6 being more susceptible. More data are needed to determine whether 7H11 MICs are systematically lower than those in MGIT. IMPORTANCE: This study confirmed that the Mycobacterium tuberculosis complex lineage 1, responsible for 28% of global tuberculosis cases, is less susceptible to pretomanid (Pa). It also refined the understanding of the intrinsic susceptibilities of lineages 5 and 6, most frequent in West Africa, and lineages 8 and 9. Regulators must review whether these in vitro differences affect the clinical efficacy of the WHO-recommended BPaL(M) regimen and set breakpoints for antimicrobial susceptibility testing accordingly. Notably, regulators should provide detailed justifications for their decisions to facilitate public scrutiny.


Assuntos
Anti-Infecciosos , Mycobacterium tuberculosis , Nitroimidazóis , Tuberculose , Humanos , Mycobacterium tuberculosis/genética , Testes de Sensibilidade Microbiana , Tuberculose/tratamento farmacológico , Tuberculose/microbiologia , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico
13.
Trials ; 25(1): 70, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38243296

RESUMO

BACKGROUND: Delamanid and bedaquiline are two of the most recently developed antituberculosis (TB) drugs that have been extensively studied in patients with multidrug-resistant TB. There is currently a need for more potent, less-toxic drugs with novel mechanisms of action that can be used in combination with these newer agents to shorten the duration of treatment as well as prevent the development of drug resistance. Quabodepistat (QBS) is a newly discovered inhibitor of decaprenylphosphoryl-ß-D-ribose-2'-oxidase, an essential enzyme for Mycobacterium tuberculosis to synthesize key components of its cell wall. The objective of this study is to evaluate the safety, efficacy, and appropriate dosing of a 4-month regimen of QBS in combination with delamanid and bedaquiline in participants with drug-susceptible pulmonary TB in comparison with the 6-month standard treatment (i.e., rifampicin, isoniazid, ethambutol, and pyrazinamide). METHODS: This phase 2b/c, open-label, randomized, parallel group, dose-finding trial will enroll approximately 120 participants (including no more than 15% with human immunodeficiency virus [HIV] coinfection) aged ≥ 18 to ≤ 65 years at screening with newly diagnosed pulmonary drug-sensitive TB from ~8 sites in South Africa. Following a screening period of up to 14 days, eligible participants will be randomized in a ratio of 1:2:2:1 to one of four arms. Randomization will be stratified by HIV status and the presence of bilateral cavitation on a screening chest x-ray. After the end of the treatment period, participants will be followed until 12 months post randomization. The primary efficacy endpoint is the proportion of participants achieving sputum culture conversion in Mycobacteria Growth Indicator Tube by the end of the treatment period. The safety endpoints consist of adverse events, clinical laboratory tests, vital signs, physical examination findings, and electrocardiographic changes. DISCUSSION: QBS's potent bactericidal activity and distinct mechanism of action (compared with other TB drugs currently available for human use) may make it an ideal candidate for inclusion in a novel treatment regimen to improve efficacy and potentially prevent resistance to concomitant TB drugs. This trial will assess the effectiveness, safety, and dosing of a new, shorter, QBS-based, combination anti-TB treatment regimen. TRIAL STATUS: ClinicalTrials.gov NCT05221502. Registered on February 3, 2022.


Assuntos
Diarilquinolinas , Infecções por HIV , Nitroimidazóis , Oxazóis , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose Pulmonar , Humanos , Antituberculosos , Ensaios Clínicos Fase II como Assunto , Quimioterapia Combinada , Infecções por HIV/tratamento farmacológico , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/microbiologia , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso
14.
Biomed Pharmacother ; 171: 116106, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38181711

RESUMO

In this study, a series of 2-Aryl-1H-benzo[d]imidazole derivatives were developed to target intra- and extracellular microtubule networks. Compounds O-7 and O-10 showed impressive anti-proliferative activity across various tested cell lines, demonstrating selectivity indexes of 151.7 and 61.9, respectively. O-7 achieved an IC50 value of 0.236 ± 0.096 µM, while O-10 showed an IC50 value of 0.622 ± 0.13 µM against A549 cell lines. The induction of early-stage apoptosis in a dose-dependent manner further underscored the potential of O-7 and O-10 as effective anti-proliferative agents. O-7 and O-10 exhibited substantial inhibition of wound closure, with wound closure percentages decreasing from 23% at 0 µM to 0.43% and 2.62% at 20 µM, respectively. Colony formation reduction rates were impressive, with O-7 at 74.2% and O-10 at 81.2%. These results indicate that the O-7 and O-10 can impede cancer cell migration and have a high potential to curtail colony formation. The mode of action investigations for O-7 and O-10 revealed that O-7 could inhibit in vitro tubulin polymerization and disrupt the intracellular microtubule cytoskeleton. This disruption led to cell cycle arrest in the G2/M phase, indicating that O-7 exerts its anticancer activity through microtubule destabilization. However, O-10 shows a different mode of action than O-7 and requires further investigation. Overall, our study showcases the potential of the synthesized benzimidazole derivatives as novel and selective anticancer agents, motivating further exploration of their pharmacological properties and therapeutic applications.


Assuntos
Antineoplásicos , Nitroimidazóis , Relação Estrutura-Atividade , Proliferação de Células , Microtúbulos , Antineoplásicos/farmacologia , Tubulina (Proteína)/metabolismo , Imidazóis/farmacologia , Apoptose , Nitroimidazóis/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Linhagem Celular Tumoral , Simulação de Acoplamento Molecular
15.
Int Immunopharmacol ; 128: 111467, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38211479

RESUMO

The adequate management of parasite co-infections represents a challenge that has not yet been overcome, especially considering that the pathological outcomes and responses to treatment are poorly understood. Thus, this study aimed to evaluate the impact of Schistosoma mansoni infection on the efficacy of benznidazole (BZN)-based chemotherapy in Trypanosoma cruzi co-infected mice. BALB/c mice were maintained uninfected or co-infected with S. mansoni and T. cruzi, and were untreated or treated with BZN. Body weight, mortality, parasitemia, cardiac parasitism, circulating cytokines (Th1/Th2/Th17); as well as heart, liver and intestine microstructure were analyzed. The parasitemia peak was five times higher and myocarditis was more severe in co-infected than T. cruzi-infected mice. After reaching peak, parasitemia was effectively controlled in co-infected animals. BZN successfully controlled parasitemia in both co-infected and T. cruzi-infected mice and improved body mass, cardiac parasitism, myocarditis and survival in co-infected mice. Co-infection dampened the typical cytokine response to either parasite, and BZN reduced anti-inflammatory cytokines in co-infected mice. Despite BZN normalizing splenomegaly and liver cellular infiltration, it exacerbated hepatomegaly in co-infected mice. Co-infection or BZN exerted no effect on hepatic granulomas, but increased pulmonary and intestinal granulomas. Marked granulomatous inflammation was identified in the small intestine of all schistosomiasis groups. Taken together, our findings indicate that BZN retains its therapeutic efficacy against T. cruzi infection even in the presence of S. mansoni co-infection, but with organ-specific repercussions, especially in the liver.


Assuntos
Doença de Chagas , Coinfecção , Miocardite , Nitroimidazóis , Esquistossomose mansoni , Camundongos , Animais , Miocardite/parasitologia , Schistosoma mansoni , Parasitemia/tratamento farmacológico , Doença de Chagas/tratamento farmacológico , Citocinas/uso terapêutico , Granuloma
16.
ACS Infect Dis ; 10(2): 662-675, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38294410

RESUMO

The Enterobacter cloacae complex (ECC) is a group of nosocomial pathogens that pose a challenge in clinical treatment due to its intrinsic resistance and the ability to rapidly acquire resistance. Colistin was reconsidered as a last-resort antibiotic for combating multidrug-resistant ECC. However, the persistent emergence of colistin-resistant (COL-R) pathogens impedes its clinical efficacy, and novel treatment options are urgently needed. We propose that azomycin, in combination with colistin, restores the susceptibility of COL-R ECC to colistin in vivo and in vitro. Results from the checkerboard susceptibility, time-killing, and live/dead bacterial cell viability tests showed strong synergistic antibacterial activity in vitro. Animal infection models suggested that azomycin-colistin enhanced the survival rate of infected Galleria mellonella and reduced the bacterial load in the thighs of infected mice, highlighting its superior in vivo synergistic antibacterial activity. Crystal violet staining and scanning electron microscopy unveiled the in vitro synergistic antibiofilm effects of azomycin-colistin. The safety of azomycin and azomycin-colistin at experimental concentrations was confirmed through cytotoxicity tests and an erythrocyte hemolysis test. Azomycin-colistin stimulated the production of reactive oxygen species in COL-R ECC and inhibited the PhoPQ two-component system to combat bacterial growth. Thus, azomycin is feasible as a colistin adjuvant against COL-R ECC infection.


Assuntos
Colistina , Nitroimidazóis , Animais , Camundongos , Colistina/farmacologia , Enterobacter cloacae , Antibacterianos/farmacologia
17.
Indian J Tuberc ; 71(1): 79-88, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38296395

RESUMO

Multi and extensively drug-resistant tuberculosis is a grave cause of global public health concern due to its high mortality and limited treatment options. We conducted this systemic review and meta-analysis to evaluate the efficacy and safety of bedaquiline and delamanid, which have been added to the WHO-recommended regimen for treating drug-resistant tuberculosis. Electronic databases were searched from their inception until December 1st, 2021, for eligible studies assessing the efficacy and safety of bedaquiline and delamanid for treating drug-resistant tuberculosis. Binary outcomes were pooled using a DerSimonian-Laird random-effects model and arcsine transformation and reported on a log scale with a 95% confidence interval (CIs). Twenty-one studies were shortlisted in which bedaquiline, delamanid, and a combination of both were administered in 2477, 937, and 169 patients. Pooled culture conversion at 6 months was 0.801 (p < 0.001), 0.849 (p = 0.059) for bedaquiline and delamanid, respectively, and 0.823 (p = 0.017), concomitantly. In the bedaquiline cohort, the pooled proportion of all-cause mortality at 6 months was reported as 0.074 (p < 0.001), 0.031 (p = 0.372) in the delamanid cohort, and 0.172 in the combined cohort. The incidence of adverse events in the bedaquiline cohort ranged from 11.1% to 95.2%, from 13.2% to 86.2% in the delamanid cohort, and 92.5% in a study in the combined cohort. The incidence of QTC prolongation reported in each cohort is as follows: bedaquiline 0.163 (p < 0.001), delamanid 0.344 (p = 0.272) and combined 0.340 (p < 0.001). Our review establishes the efficacy of delamanid, bedaquiline, and their combined use in treating drug-resistant tuberculosis with reasonable rates of culture conversion, low mortality rates, and safety of co-administration, as seen with their effect on the QTc interval.


Assuntos
Antituberculosos , Nitroimidazóis , Oxazóis , Tuberculose Resistente a Múltiplos Medicamentos , Adulto , Humanos , Antituberculosos/efeitos adversos , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Diarilquinolinas/efeitos adversos , Resultado do Tratamento
18.
Sci Rep ; 14(1): 1900, 2024 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-38253756

RESUMO

Bacterial resistance to antimicrobials is fast becoming a big challenge as resistance to multiple drugs is rising rapidly. The emergence of resistant Staphylococcus aureus worldwide is life-threatening in both humans and animals and yet little is known about the burden of antimicrobial resistance (AMR) in developing countries including Uganda. Therefore, the aims of this study were to determine the prevalence of antimicrobial resistant S. aureus among humans and animals as well as assess the perceptions and practices of farmers in Kamuli and Isingiro districts in Uganda regarding AMR of S. aureus. A cross-sectional study was conducted between July and September 2020 in 147 randomly selected cattle-keeping households in Isingiro and Kamuli districts. A structured questionnaire uploaded in the Kobo-collect online data collection tool was used to assess farmers' perceptions and practices pertaining to AMR in each of the selected households. Nasal swabs (n = 147) were collected from both cattle and humans (farmers). Bacterial isolation and confirmation was done using Gram-staining and biochemical tests. This was followed by antimicrobial susceptibility testing (AST) using the Kirby Bauer disc diffusion method. Only 14/147 (9.5%) cattle samples and 45/147(30.6%) human samples tested positive for S. aureus. All cattle S. aureus isolates were resistant to Nitroimidazoles while 92.9% were resistant to Penicillins. None of the isolates were resistant to Fluoroquinolones and Aminoglycosides. All the 14 isolates exhibited AMR to at least one of the assessed antibiotics and 92.9% (13/14) showed evidence of multidrug resistance (MDR). Likewise, S. aureus human isolates showed high levels of resistance to Nitroimidazoles (100%) and Penicillins (93.3%), with none of the isolates having resistance to Aminoglycosides, and only one exhibiting resistance to Fluoroquinolones (2.2%). All the 45 human isolates exhibited AMR to at least one antibiotic while 93% (42/45) had MDR. Most farmers had good perceptions of AMR, with a significantly higher proportion of respondents from Isingiro than Kamuli showing a better understanding of AMR. Antibiotic prophylaxis was reported to be the least practiced measure of diseases and parasites control (17.0%), with more farmers in Isingiro (33.3%) undertaking it than those in Kamuli (1.3%) (p < 0.001). Penicillins and Nitroimidazoles were reported to be the most used antibiotics among cattle and humans. This study provides evidence of occurrence of S. aureus resistance to antimicrobials commonly used in both humans and livestock in Isingiro and Kamuli districts. Farmers had good perceptions regarding AMR as well as good antimicrobial use practices which can form a basis for mitigation of AMR.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Nitroimidazóis , Infecções Estafilocócicas , Humanos , Bovinos , Animais , Staphylococcus aureus , Uganda/epidemiologia , Estudos Transversais , Agricultura , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/veterinária , Antibacterianos/farmacologia , Penicilinas , Aminoglicosídeos , Fluoroquinolonas
19.
Talanta ; 271: 125679, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38245958

RESUMO

The development of efficient, rapid, portable, and accurate analysis of veterinary drug residues in food matrices is in great demand for food safety assessment. Here, we have developed a smartphone-integrated platform for fluorometric quantification of metronidazole (MNZ) residues and constructed a sensor array for discrimination of different nitroimidazole antibiotics (NIIMs). Multicolor CDs (B-CDs, C-CDs, Y-CDs, and R-CD) were prepared and showed different fluorescence response to MNZ. The fluorescence of C-CDs was quenched Because of the inner filter effect (IFE) between the C-CDs and MNZ, while that of R-CDs was enhanced due to the passivation of surface defects by MNZ. Based on the response pattern, the fluorometric quantification of MNZ based on the fluorescence images of C-CD + R-CD system (R/G values) was achieved with a low detection limit of 0.45 µM. By designing a smartphone-integrated platform, the analysis can be completed within 20 min. In addition, a fluorescence sensor array based C-CDs and R-CDs was also developed. The unique fingerprint of each NIIMs was obtained by linear discriminant analysis (LDA) of the response patterns, indicating an effective discrimination of five NIIMs. Moreover, the platform was used for quantification of MNZ in food samples and the recoveries were within 84.0-106.3 % with relative standard deviations 1.2-10.2 %. Therefore, the proposed method shows great potential as a universal platform for rapid detection of veterinary drug residues.


Assuntos
Nitroimidazóis , Pontos Quânticos , Drogas Veterinárias , Antibacterianos , Carbono , Fluorometria , Corantes Fluorescentes , Espectrometria de Fluorescência
20.
Toxins (Basel) ; 16(1)2024 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-38251253

RESUMO

Even though there are guidelines for the management of snakebite envenoming (SBE), the use of antibiotics in this pathology remains controversial. The aim of this study is to provide a narrative review of the literature and recommendations based on the best available evidence regarding antibiotic use in SBE. We performed a narrative review of relevant literature regarding SBE and antibiotic use as prophylaxis or treatment. A total of 26 articles were included. There is wide use of antibiotics in SBE; nevertheless, infection was not necessarily documented. The antibiotics used varied according to the study, from beta lactams to lincosamide and nitroimidazoles, and from monotherapy to combined antimicrobials. The most common recommendations were to manage skin and soft tissue infections and avoid infectious complications, but these suggestions are not necessarily based on bacteriological findings. Prophylactic use of antibiotics in SBE is discouraged in most studies. Antibiotic prescription in SBE should be based on the susceptibility of microorganisms isolated from the affected tissue or identified in snakes' oral cavities. Antibiotics should be reserved only for patients with a demonstrated infection, or those at a high risk of developing an infection, i.e., presenting severe local envenoming, local signs of infection, or those with incorrect manipulation of wounds. Prospective studies are needed to correlate microbiological findings at the wound site and the response to antibiotic use.


Assuntos
Gestão de Antimicrobianos , Nitroimidazóis , Mordeduras de Serpentes , Humanos , Antibacterianos/uso terapêutico , Mordeduras de Serpentes/tratamento farmacológico , Boca
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