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result(s) for
"Spiramycin"
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Rapid separation of bile acid isomers via ion mobility mass spectrometry by complexing with spiramycin
2024
Bile acid (BA) is one of the main active components of bile and has multiple isomers, the structure or content of its isomers often changes due to diseases and other health problems; thus, the accurate detection of BA isomers is very important. In this study, two groups of BA isomers of glycine-conjugated BAs and taurine-conjugated BAs were simultaneously separated and quantitatively analyzed by ion mobility mass spectrometry (IM-MS). Especially, baseline mobility separation between the isomers was achieved by the formation of binary complexes via simple interaction with spiramycin (SPM), for which a separation resolution (Rp-p) of 1.96 was reached. Moreover, BA isomers were quantitatively analyzed, and the limit of detection (LOD) of absolute quantification for TCDCA/TUDCA and GUDCA/GCDCA/GHDCA was 0.514 and 0.611 ng∙mL−1, respectively; the LODs for molar ratio ranges of relative quantification for TCDCA/TUDCA, GUDCA/GHDCA, and GCDCA/GHDCA were 1:18–30:1, 1:18–21:1, and 1:19–21:1, respectively. Additionally, BA isomers analyzed in pig bile powder and bear bile powder were measured, which were in good consistency with those labeled, revealing the differences in BA composition and content between the two powders. Finally, BA detection and recovery analyses were performed on serum samples, with a recovery rate of ≥73.69%, RSD of ≤6.8%, and SR (standard deviation of recoveries, the degree of difference between measured values and average recovery) of ≤1.27. Due to the simple, rapid, and lack of need for complex sample preparation and chromatographic separation, the proposed method can be an effective method for BA detection in practical samples.
Journal Article
Co-delivery of spiramycin and curcumin nanoemulsions for treating acute (RH strain) and chronic (Tehran strain) toxoplasmosis in BALB/c mice
by
Amani, Amir
,
Valian, Hossein Keshavarz
,
Mohebali, Mehdi
in
Animal models
,
Animals
,
Antibiotics
2025
This study aimed to develop and evaluate a nanoemulsion containing spiramycin and curcumin (NE-CS) to enhance these compounds’ bioavailability and efficacy against acute and chronic toxoplasmosis in mice. Nanoemulsion containing spiramycin and curcumin (NE-CS), spiramycin nanoemulsion (NE-Spi), and a nanoemulsion without the drug (NE) were prepared via spontaneous emulsification and characterized for particle size and zeta potential. Their in vitro activity was tested against tachyzoites of
T. gondii
, RH strain, at different concentrations (250, 125, 62.5, and 31.25 µg/ml) and time points (30, 60, 90, and 120 min). In vivo, BALB/c mice infected with RH and Tehran strains were treated with NE-CS (25 mg/kg/day curcumin + 50 mg/kg/day spiramycin), NE-Spi (50 mg/kg/day), S-Spi, and NE, with infected/untreated mice as controls. Survival time, tachyzoite counts in peritoneal fluid (acute phase), and number and size of tissue cysts (chronic phase) were assessed microscopically. NE-CS significantly decreased the intracellular multiplication of
T. gondii
tachyzoites (5 ± 2.78 × 10
4
) compared with that of the infected/untreated group (3509 ± 435.39 × 10
4
). Oral administration of NE-CS improved therapeutic outcomes in vivo, prolonged survival time in mice (13 days), reduced parasitemia, and decreased both the number (43 ± 5.78) and size (4 ± 1.11 µm) of brain cysts compared to the infected/untreated group (380 ± 17.22 and 112.8 ± 8.28 µm, respectively). This study demonstrated the in vitro efficiency of nanoemulsion co-delivery of curcumin and spiramycin for increasing tachyzoite death, and indicated the possibility of NE-CS and NE-Spi for treating acute and chronic toxoplasmosis in murine models. However, further investigations are needed to confirm their safety and effectiveness across broader models.
Graphical abstract
Journal Article
Essential oil of oregano
by
dos Santos, Yasmin Munhoz
,
da Silva Sanfelice, Raquel Arruda
,
Concato-Lopes, Virgínia Marcia
in
Health aspects
,
Infection
,
Necrosis
2024
Toxoplasmosis poses a global health threat, ranging from asymptomatic cases to severe, potentially fatal manifestations, especially in immunocompromised individuals and congenital transmission. Prior research suggests that oregano essential oil (OEO) exhibits diverse biological effects, including antiparasitic activity against Toxoplasma gondii. Given concerns about current treatments, exploring new compounds is important. This study was to assess the toxicity of OEO on BeWo cells and T. gondii tachyzoites, as well as to evaluate its effectiveness in in vitro infection models and determine its direct action on free tachyzoites. OEO toxicity on BeWo cells and T. gondii tachyzoites was assessed by MTT and trypan blue methods, determining cytotoxic concentration (CC.sub.50), inhibitory concentration (IC.sub.50), and selectivity index (SI). Infection and proliferation indices were analyzed. Direct assessments of the parasite included reactive oxygen species (ROS) levels, mitochondrial membrane potential, necrosis, and apoptosis, as well as electron microscopy. Oregano oil exhibited low cytotoxicity on BeWo cells (CC.sub.50: 114.8 µg/mL ± 0.01) and reduced parasite viability (IC.sub.50 12.5 ± 0.06 µg/mL), demonstrating 9.18 times greater selectivity for parasites than BeWo cells. OEO treatment significantly decreased intracellular proliferation in infected cells by 84% after 24 h with 50 g/mL. Mechanistic investigations revealed increased ROS levels, mitochondrial depolarization, and lipid droplet formation, linked to autophagy induction and plasma membrane permeabilization. These alterations, observed through electron microscopy, suggested a necrotic process confirmed by propidium iodide labeling. OEO treatment demonstrated anti-T. gondii action through cellular and metabolic change while maintaining low toxicity to trophoblastic cells.
Journal Article
Pretreatment of spiramycin fermentation residue using hyperthermophilic digestion: quick startup and performance
by
Gao, Yingxin
,
Awad, Mohammed
,
Tian, Zhe
in
Acidification
,
Anaerobic digestion
,
Anaerobic treatment
2018
This study aimed to evaluate the feasibility of hyperthermophilic anaerobic digestion at 70 °C in the pretreatment of spiramycin fermentation residue. By feeding municipal excess sludge under a solid retention time of 5 days, the hyperthermophilic digester was successfully started up within 3 days from mesophilic digestion by a one-step temperature increase from 35 to 70 °C. MiSeq sequencing showed the fast establishment of thermophilic fermenting bacterial communities in 3 days immediately after the temperature increase, with increases in abundance of Coprothermobacter, Spirochaetaceae_uncultured and Fervidobacterium from <0.001%, 1.06% and <0.001% to 33.77%, 11.65% and 3.42%, respectively. The feasibility of hyperthermophilic digestion for spiramycin residue was evaluated in batch experiments for 7 days. Hyperthermophilic digestion considerably reduced antibiotic concentrations, with removal efficiencies of 55.3% and 99.0% for the spiramycin residue alone and its mixture with hyperthermophilic sludge, respectively. At the same time, the abundances of four macrolide-lincosamide-streptogramin resistance genes were also reduced within 7 days, due to the decrease of their corresponding hosts. These results suggest that hyperthermophilic digestion could easily be started up from mesophilic digestion and might be a suitable pretreatment approach for spiramycin residue.
Journal Article
Spiramycin-loaded maltodextrin nanoparticles as a promising treatment of toxoplasmosis on murine model
by
Abdel-Wahab, Ayman A.
,
Sharaf, Soraya A.
,
Mohsen, Khloud K.
in
albino
,
Animal models
,
Animals
2024
Despite being the initial choice for treating toxoplasmosis, sulfadiazine and pyrimethamine have limited effectiveness in eliminating the infection and were linked to a variety of adverse effects. Therefore, the search for new effective therapeutic strategies against toxoplasmosis is still required. The current work is the first research to assess the efficacy of spiramycin-loaded maltodextrin nanoparticles (SPM-loaded MNPs) as a novel alternative drug therapy against toxoplasmosis in a murine model. Fifty laboratory-bred Swiss albino mice were divided into five groups: normal control group (GI,
n
= 10), positive control group (GII,
n
= 10), orally treated with spiramycin (SPM) alone (GIII,
n
= 10), intranasal treated with SPM-loaded MNPs (GIV,
n
= 10), and orally treated with SPM-loaded MNPs (GV,
n
= 10). Cysts of
Toxoplasma gondii
ME-49 strain were used to infect the mice. Tested drugs were administered 2 months after the infection. Drug efficacy was assessed by counting brain cysts, histopathological examination, and measures of serum CD19 by flow cytometer. The orally treated group with SPM-loaded MNPs (GV) showed a marked reduction of brain cyst count (88.7%), histopathological improvement changes, and an increasing mean level of CD19 (80.2%) with significant differences. SPM-loaded MNPs showed potent therapeutic effects against chronic toxoplasmosis. Further research should be conducted to assess it in the treatment of human toxoplasmosis, especially during pregnancy.
Graphical Abstract
Journal Article
Panton-Valentine Leukocidin–Secreting Staphylococcus aureus Pneumonia Complicating COVID-19
by
Loïez, Caroline
,
Six, Sophie
,
Le Guern, Rémi
in
Adult
,
Anti-Bacterial Agents - therapeutic use
,
Bacterial Toxins - biosynthesis
2020
Necrotizing pneumonia induced by Panton-Valentine leukocidin-secreting Staphylococcus aureus is a rare but life-threatening infection that has been described in patients after they had influenza. We report a fatal case of this superinfection in a young adult who had coronavirus disease.
Journal Article
Mitochondrial dysfunction induced by bedaquiline as an anti-Toxoplasma alternative
2023
Toxoplasma gondii is a zoonotic parasite that infects one-third of the world's population and nearly all warm-blooded animals. Due to the complexity of T. gondii's life cycle, available treatment options have limited efficacy. Thus, there is an urgent need to develop new compounds or repurpose existing drugs with potent anti-Toxoplasma activity. This study demonstrates that bedaquiline (BDQ), an FDA-approved diarylquinoline antimycobacterial drug for the treatment of tuberculosis, potently inhibits the tachyzoites of T. gondii. At a safe concentration, BDQ displayed a dose-dependent inhibition on T. gondii growth with a half-maximal effective concentration (EC.sub.50) of 4.95 [mu]M. Treatment with BDQ significantly suppressed the proliferation of T. gondii tachyzoites in the host cell, while the invasion ability of the parasite was not affected. BDQ incubation shrunk the mitochondrial structure and decreased the mitochondrial membrane potential and ATP level of T. gondii parasites. In addition, BDQ induced elevated ROS and led to autophagy in the parasite. By transcriptomic analysis, we found that oxidative phosphorylation pathway genes were significantly disturbed by BDQ-treated parasites. More importantly, BDQ significantly reduces brain cysts for the chronically infected mice. These results suggest that BDQ has potent anti-T. gondii activity and may impair its mitochondrial function by affecting proton transport. This study provides bedaquiline as a potential alternative drug for the treatment of toxoplasmosis, and our findings may facilitate the development of new effective drugs for the treatment of toxoplasmosis.
Journal Article
Identification of 4″-isovaleryl-spiramycin III produced by Bacillus sp. fmbJ
by
Deng, Yang
,
Bie, Xiaomei
,
Lu, Fengxia
in
Anti-Bacterial Agents - biosynthesis
,
Anti-Bacterial Agents - chemistry
,
Anti-Bacterial Agents - isolation & purification
2014
The production of secondary metabolites with antibiotic properties is a common characteristic to Bacillus spp. These metabolites not only have diverse chemical structures but also have a wide range of bioactivities with medicinal and agricultural interests such as antibiotic. Bacillus sp. fmbJ has been found to produce lipopeptides fengycin and surfactin in accordance with our previous report. In this study, another antimicrobial substance was separated and purified from the culture supernatant of strain fmbJ using the silica gel column chromatography and preparative reversed-phase high-performance liquid chromatography. By means of electrospray ionization mass spectroscopy, infrared spectroscopy, and nuclear magnetic resonance, the antagonistic compound was determined to be 4″-isovaleryl-spiramycin III with the molecular weight of 982 Da. This report is the first to introduce the finding of spiramycin produced from Bacillus sp. The study provides a novel source for the production of spiramycin in pharmaceutical industries.
Journal Article
A Systematic Review and Meta-Analysis of the Efficacy of Anti-Toxoplasma gondii Medicines in Humans
by
Lindsay, David S.
,
Wei, Hai-Xia
,
Wei, Shan-Shan
in
Acquired immune deficiency syndrome
,
Acquired Immunodeficiency Syndrome - complications
,
Acquired Immunodeficiency Syndrome - transmission
2015
No effective drug and definitive \"gold standard\" treatment for Toxoplasma gondii (T. gondii) infection has been available so far, though some medicines have been commonly used in the treatment of T. gondii infection, such as spiramycin, azithromycin, traditional Chinese medicine (TCM), pyrimethamine- sulfadiazine (P-S), trimethoprim-sulfamethoxazole (TMP-SMX), and pyrimethamine-clindamycin (P-C). A systematic review and meta-analysis were performed to compare the efficacies of these conventional medicines in the treatment. Cohort studies for the treatment of acute T. gondii infection were searched from PubMed, Google Scholar, ect. All the cases number for different group extracted from each included literature were input to meta-analysis 3.13 software to calculate the pooled negative conversion rate (NCR), cure rate (CR) or vertical transmission rate based on their sample size and weight. The pooled NCR with 95% confidence intervals (CI) was used to evaluate the overall rate of a diagnosis positive result conversion to a negative result after treatment, which of spiramycin, azithromycin and TCM were 83.4% (95%CI, 72.1%-90.8%), 82.5% (95%CI, 75.9%-87.6%), and 85.5% (95%CI, 71.3%-93.3%) respectively, with no statistical difference between them. The pooled CR with 95% CI was used to evaluate the overall rate of complete disappearance of clinical symptoms for toxoplasmic encephalitis after therapy, which of P-S, TMP-SMX, and P-C were 49.8% (95%CI, 38. 8% -60.8%), 59.9% (95%CI, 48.9%-70.0%), and 47.6% (95%CI, 24.8%-71.4%) respectively, with no statistical difference between them. Primary T. gondii infection in pregnancy was treated mainly with spiramycin alone or combined with other drugs, and the pooled rate of vertical transmission was about 9.9% (95%CI, 5.9%-16.2%) after therapy. Toxoplasmic encephalitis in AIDS patients was usually treated with sulfonamides combined with other drugs and the pooled CR was 49.4% (95%CI, 37.9%-60.9%).
Journal Article
Anti-Inflammatory Effects of Spiramycin in LPS-Activated RAW 264.7 Macrophages
by
Kang, Hyun-Kyu
,
Kang, Jin-Kyu
,
Hyun, Chang-Gu
in
Animals
,
Anti-Inflammatory Agents - metabolism
,
Anti-Inflammatory Agents - pharmacology
2022
Drug repurposing is a simple concept with a long history, and is a paradigm shift that can significantly reduce the costs and accelerate the process of bringing a new small-molecule drug into clinical practice. We attempted to uncover a new application of spiramycin, an old medication that was classically prescribed for toxoplasmosis and various other soft-tissue infections; specifically, we initiated a study on the anti-inflammatory capacity of spiramycin. For this purpose, we used murine macrophage RAW 264.7 as a model for this experiment and investigated the anti-inflammatory effects of spiramycin by inhibiting the production of pro-inflammatory mediators and cytokines. In the present study, we demonstrated that spiramycin significantly decreased nitric oxide (NO), interleukin (IL)-1β, and IL-6 levels in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Spiramycin also inhibited the expression of NO synthase (iNOS), potentially explaining the spiramycin-induced decrease in NO production. In addition, spiramycin inhibited the phosphorylation of mitogen-activated protein kinases (MAPKs); extracellular signal-regulated kinase (ERK) and c-Jun N terminal kinase (JNK) as well as the inactivation and subsequent nuclear translocation of nuclear factor κB (NF-κB). This indicated that spiramycin attenuates macrophages’ secretion of IL-6, IL-1β, and NO, inducing iNOS expression via the inhibition of the NF-κB and MAPK signaling pathways. Finally, we tested the potential application of spiramycin as a topical material by human skin primary irritation tests. It was performed on the normal skin (upper back) of 31 volunteers to determine whether 100 μM and μM of spiramycin had irritation or sensitization potential. In these assays, spiramycin did not induce any adverse reactions. In conclusion, our results demonstrate that spiramycin can effectively attenuate the activation of macrophages, suggesting that spiramycin could be a potential candidate for drug repositioning as a topical anti-inflammatory agent.
Journal Article