Conventional Antibiotic Therapy Research Articles

Photodynamic therapy to control microbial biofilms.

Microorganisms thrive in well-organized biofilm ecosystems. Biofilm-associated cells typically show increased resistance to antibiotics and contribute significantly to treatment failure. This has prompted investigations aimed at developing advanced and novel antimicrobial approaches that could effectively overcome the shortcomings associated with conventional antibiotic therapy. Studies are ongoing to develop effective curative strategies ranging from the use of peptides, small molecules, nanoparticles to bacteriophages, sonic waves, and light energy targeting various structural and physiological aspects of biofilms. In photodynamic therapy, a light source of a specific wavelength is used to irradiate non-toxic photosensitizers such as tetrapyrroles, synthetic dyes or, naturally occurring compounds to generate reactive oxygen species that can exert a lethal effect on the microbe especially by disrupting the biofilm. The photosensitizer preferentially binds to and accumulates in the microbial cells without causing any damage to the host tissue. Currently, photodynamic therapy is increasingly being used for the treatment of oral caries and dental plaque, chronic wound infections, infected diabetic foot ulcers, cystic fibrosis, chronic sinusitis, implant device-associated infections, etc. This approach is recognized as safe, as it is non-toxic and minimally invasive, making it a reliable, realistic, and promising therapeutic strategy for reducing the microbial burden and biofilm formation in chronic infections. In this review article, we discuss the current and future potential strategies of utilizing photodynamic therapy to extend our ability to impede and eliminate biofilms in various medical conditions.

Clinical and cost-effectiveness analysis of the methods of therapy and prevention of andrological pathologies using drugs based on ozone and nano-biomaterials

Practical implementation of the latest pharmacological developments is possible provided that their clinical and economic efficiency is assessed. At the same time, the issues of economic feasibility of using the latest diagnostic techniques, as well as means of therapy and prevention of the male reproductive pathologies system remain poorly studied. The aim of the work was to analyze the cost-effectiveness of methods of therapy and prevention of andrological diseases with drugs based on ozonated and nanobiomaterials. The following research tasks were set: to establish the clinical and economic effectiveness of the method of therapy of males for nonspecific balanoposthitis with ozone-containing drugs OCO and Prozon and to determine the economic effect of treatment and prevention methods of alimentary and toxic reproductive diseases in males using drugs based on nanobiomatersals. Clinical and economic efficacy of the treatment method of males with nonspecific balanoposthitis was established by estimating the cost of treatment of animals group with OCO and Prozon by changes in the diseaseduration from treatment to recovery of the fetus compared with conventional antibiotic therapy. The economic effect of therapy and prevention methodsof alimentary and toxic reproductive diseases was evaluated by changes in sperm quality and calculated the average number of additional sperm doses received from the males. The duration of the period from the beginning of treatment to recovery in boars with the use of ozone-containing drugs was: when using OKO – 6.7 ± 0.18 days, and Prozon – 6.1 ± 0.21 days, which was less by 0.9–1.5 days compared with the introduction of gentamicin ointment. And in bulls when using the drug OKO – by 6.7 ± 0.33 days, and Prozon – 5.14 ± 0.26 days, which was less by 1.1–2.7 days. At the same time, the cost of treatment of one male has decreased by 42.3 % with the use of OKO and 37.5 % – Prozon. Despite the higher cost of the drug Prozon, its use is more effective due to faster recovery of the malts. An increase in ejaculate volume, sperm motility, concentration based on the results of correction of alimentary and toxic reproductive diseases has been established; the number of sperm with morphological abnormalities, on the other side, was probably reduced. The complex drug “Karafand+OV,Zn” had a high economic effect due to the possibility of additional receipt 6 spermodoses from the boar and 22 from the bull for the correction of reproductive diseases of the alimentary type and 6 spermodoses from the boar and 20 from the bull – toxic type.

Pharmacokinetics and Time-Kill Study of Inhaled Antipseudomonal Bacteriophage Therapy in Mice.

Inhaled bacteriophage (phage) therapy is a potential alternative to conventional antibiotic therapy to combat multidrug-resistant (MDR) Pseudomonas aeruginosa infections. However, pharmacokinetics (PK) and pharmacodynamics (PD) of phages are fundamentally different from antibiotics and the lack of understanding potentially limits optimal dosing. The aim of this study was to investigate the in vivo PK and PD profiles of antipseudomonal phage PEV31 delivered by pulmonary route in immune-suppressed mice. BALB/c mice were administered phage PEV31 at doses of 107 and 109 PFU by the intratracheal route. Mice (n = 4) were sacrificed at 0, 1, 2, 4, 8, and 24 h posttreatment and various tissues (lungs, kidney, spleen, and liver), bronchoalveolar lavage fluid, and blood were collected for phage quantification. In a separate study combining phage with bacteria, mice (n = 4) were treated with PEV31 (109 PFU) or phosphate-buffered saline (PBS) at 2 h postinoculation with MDR P. aeruginosa Infective PEV31 and bacteria were enumerated from the lungs. In the phage-only study, the PEV31 titer gradually decreased in the lungs over 24 h, with a half-life of approximately 8 h for both doses. In the presence of bacteria, in contrast, the PEV31 titer increased by almost 2-log10 in the lungs at 16 h. Furthermore, bacterial growth was suppressed in the PEV31-treated group, while the PBS-treated group showed exponential growth. Of the 10 colonies tested, four phage-resistant isolates were observed from the lung homogenates sampled at 24 h after phage treatment. These colonies had a different antibiogram to the parent bacteria. This study provides evidence that pulmonary delivery of phage PEV31 in mice can reduce the MDR bacterial burden.

Cysteine-rich antimicrobial peptides from plants: The future of antimicrobial therapy.

There has been a spurt in the spread of microbial resistance to antibiotics due to indiscriminate use of antimicrobial agents in human medicine, agriculture, and animal husbandry. It has been realized that conventional antibiotic therapy would be less effective in the coming decades and more emphasis should be given for the development of novel antiinfective therapies. Cysteine rich peptides (CRPs) are broad-spectrum antimicrobial agents that modulate the innate immune system of different life forms such as bacteria, protozoans, fungi, plants, insects, and animals. These are also expressed in several plant tissues in response to invasion by pathogens, and play a crucial role in the regulation of plant growth and development. The present work explores the importance of CRPs as potent antimicrobial agents, which can supplement and/or replace the conventional antibiotics. Different plant parts of diverse plant species showed the presence of antimicrobial peptides (AMPs), which had significant structural and functional diversity. The plant-derived AMPs exhibited potent activity toward a range of plant and animal pathogens, protozoans, insects, and even against cancer cells. The cysteine-rich AMPs have opened new avenues for the use of plants as biofactories for the production of antimicrobials and can be considered as promising antimicrobial drugs in biotherapeutics.

In silico identification of novel PrfA inhibitors to fight listeriosis: A virtual screening and molecular dynamics studies

Listeria monocytogenes is considered to be one of the most dangerous foodborne pathogens as it can cause listeriosis, a life-threatening human disease. While the incidence of listeriosis is very low its fatality rate is exceptionally high. Because many multi-resistance Listeria monocytogenes strains that do not respond to conventional antibiotic therapy have been recently described, development of new antimicrobials to fight listeriosis is necessary. The positive regulatory factor A (PrfA) is a key homodimeric transcription factor that modulates the transcription of multiple virulence factors which are ultimately responsible of Listeria monocytogenes’ pathogenicity. In the present manuscript we describe several new potential PrfA inhibitors that were identified after performing ligand-based virtual screening followed by molecular docking calculations against the wild-type PrfA structure. The three top-scored drug-likeness inhibitors bound to the wild-type PrfA structure were further assessed by Molecular Dynamics (MD) simulations. Besides, the three top-scored inhibitors were docked into a constitutive active apoPrfA mutant structure and the corresponding complexes were also simulated by MD. According to the obtained data, PUBChem 87534955 (P875) and PUBChem 58473762 (P584) may not only bind and inhibit wild-type PrfA but the aforementioned apoPrfA mutant as well. Therefore, P875 and P584 might represent good starting points for the development of a completely new set of antimicrobial agents to treat listeriosis.

Antibiotic-Resistant and Non-Resistant Bacteria Display Similar Susceptibility to Dielectric Barrier Discharge Plasma.

Here, we examined whether antibiotic-resistant and non-resistant bacteria show a differential susceptibility to plasma treatment. Escherichia coli DH5α were transformed with pPRO-EX-HT-CAT, which encodes an ampicillin resistance gene and chloramphenicol acetyltransferase (CAT) gene, and then treated with a dielectric barrier discharge (DBD) plasma torch. Plasma treatment reduced the viable cell count of E. coli after transformation/selection and further cultured in ampicillin-containing and ampicillin-free medium. However, there was no significant difference in viable cell count between the transformed and untransformed E. coli after 1 min- and 2 min-plasma treatment. Furthermore, the enzyme-linked immunosorbent assay (ELISA) and acetyltransferase activity assay showed that the CAT activity was reduced after plasma treatment in both transformed and selected E. coli grown in ampicillin-containing or ampicillin-free medium. Loss of lipopolysaccharide and DNA damage caused by plasma treatment were confirmed by a Limulus test and polymerase chain reaction, respectively. Taken together, these findings suggest the plasma acts to degrade components of the bacteria and is therefore unlikely to display a differential affect against antibiotic-resistant and non-resistant bacteria. Therefore, the plasma method may be useful in eliminating bacteria that are recalcitrant to conventional antibiotic therapy.

The Chemistry of Antibiofilm Phytocompounds.

Phytocompounds are long known for their therapeutic uses due to their competence as antimicrobial agents. The antimicrobial activity of these bioactive compounds manifests their ability as an antibiofilm agent and is thereby proved to be competent to treat the widespread biofilm-associated chronic infections. The rapid development of antibiotic resistance in bacteria has made the treatment of these infections almost impossible by conventional antibiotic therapy, which forced a switch-over to the use of phytocompounds. The present overview deals with the classification of a huge array of phytocompounds according to their chemical nature, detection of their target pathogen, and elucidation of their mode of action.

Antibiotic-resistant acne vulgaris treated with oral isotretinoin in a patient with thalassemia minor

Acne vulgaris is very common among adolescents and young adults. Permanent scarring, poor self-image, depression, and anxiety can result from it. The acne treatment options include topical therapies, systemic agents, physical modalities, lasers, photodynamic therapy or combinations. Oral isotretinoin is widely recognised as a very effective treatment for severe acne. However, it may cause adverse effects. We report a case of an 18-year-old man affected by thalassemia minor treated with oral isotretinoin because of a severe form of acne unresponsive to conventional oral antibiotic therapy. During the treatment clinical and biochemical evaluations were closely monitored each month in order to discover potential adverse effects of isotretinoin and the impact over thalassemia. After 9 months of oral isotretinoin application we can tell that the drug was well tolerated by the patient, the acne totally cleared, and the thalassemia did not deteriorate. In conclusion, although a highly effective drug, isotretinoin use is limited by its side effects. However, patients may accept these procedures to improve the psychosocial effects of acne, because it can target all aspects of acne pathology. Something else, it is the choice of treatment in antibiotic-resistant forms of acne. It has been seen that the oral isotretinoin could be successfully used in patients with severe acne suffering from thalassemia minor in which the antibiotic treatment failed with the explicit requirement for strict clinical and biochemical follow-up.

Seagrass Halodule pinifolia active constituent 4-methoxybenzioic acid (4-MBA) inhibits quorum sensing mediated virulence production of Pseudomonas aeruginosa

Biofilm associated, multidrug resistant Pseudomonas aeruginosa infection remain a challenging problem in the clinical field since the conventional antibiotic therapy are largely inefficient and new approaches are needed. Inactivating the QS virulence mechanism with anti-infective agent is an attractive approach to prevent bacterial infections without resistance development. Seagrass Halodule pinifolia (Miki) Hartog has been shown to exhibit potential antimicrobial activities against harmful pathogens. Our study investigated the effects of seagrass H. pinifolia leaf extract and its bioactive constituents on QS-mediated virulence factors and biofilm formation in P. aerugonasa PAO1. Preliminary screening on antibiofilm activity showed that the methanolic extract of H. pinifolia exhibited potential inhibition of biofilm formation (96%) as compared to the control respectively. Further, the potential extract was column fractionated and the active fraction was characterized by GC-MS. In total eight active compounds (protocatacheuic acid (69.3%), rosmarinic acid (63.5%), caffeic acid (59.18%), p-coumaric acid (59.08%), 4-methoxybenzoic acid (53.19%), naringenin (52.9%), vanillic acid (49.19%), 4-hydroxybenzoic acid (41.73%)) were profiled from fraction 2 and were purified by HPLC, structurally confirmed by NMR. Among the eight compounds studied, 4-methoxybenzoic acid (4-MBA) showed an effective inhibition of bacterial growth and was considered as a lead molecule with minimum inhibitory concentration (MIC) of 62.5 μg/mL. Further the effect of 4-MBA on QS mediated virulence factors demonstrated that the compound at MIC concentration reduced the virulence factor production such as elastase (87.5%), protease (79.38%), pyocyanin (91.46%), rhamnolipid (86%), alginate (86%), chitinase (55%), exopolysaccharide production (83.72%) and CSH (78.39%) over the control respectively. Moreover, 4-MBA down regulated the QS-mediated virulence transcript levels upon treatment with 4-MBA. The present findings suggests that seagrasses may act as a newer source for the marine based drug discovery and the lead compound 4-MBA derived from H. pinifolia may act as anti-infective agent against P. aeruginosa as it controls the QS-mediated virulence production.

Nucleic Acid Hybrids as Advanced Antibacterial Nanocarriers.

Conventional antibiotic therapy is often challenged by poor drug penetration/accumulation at infection sites and poses a significant burden to public health. Effective strategies to enhance the therapeutic efficacy of our existing arsenal include the use of nanoparticulate delivery platforms to improve drug targeting and minimize adverse effects. However, these nanocarriers are often challenged by poor loading efficiency, rapid release and inefficient targeting. Nucleic acid hybrid nanocarriers are nucleic acid nanosystems complexed or functionalized with organic or inorganic materials. Despite their immense potential in antimicrobial therapy, they are seldom utilized against pathogenic bacteria. With the emergence of antimicrobial resistance and the associated complex interplay of factors involved in antibiotic resistance, nucleic acid hybrids represent a unique opportunity to deliver antimicrobials against resistant pathogens and to target specific genes that control virulence or resistance. This review provides an unbiased overview on fabricating strategies for nucleic acid hybrids and addresses the challenges of pristine oligonucleotide nanocarriers. We report recent applications to enhance pathogen targeting, binding and control drug release. As multifunctional next-generational antimicrobials, the challenges and prospect of these nanocarriers are included.

Combinational therapy with antibiotics and antibiotic-loaded adipose-derived stem cells reduce abscess formation in implant-related infection in rats

Implant-related infection is difficult to treat without extended antibiotic courses. However, the long-term use of antibiotics has led to the development of multidrug- and methicillin-resistant Staphylococcusaureus. Thus, alternatives to conventional antibiotic therapy are needed. Recently, mesenchymal stem cells have been shown to have antimicrobial properties. This study aimed to evaluate the antimicrobial activity and therapeutic effect of local treatment with antibiotic-loaded adipose-derived stem cells (ADSCs) plus an antibiotic in a rat implant-associated infection model. Liquid chromatography/tandem mass spectrometry revealed that ADSCs cultured in the presence of ciprofloxacin for 24 h showed time-dependent antibiotic loading. Next, we studied the therapeutic effects of ADSCs and ciprofloxacin alone or in combination in an implant-related infection rat model. The therapeutic effects of ADSCs plus antibiotics, antibiotics, and ADSCs were compared with no treatment as a control. Rats treated with ADSCs plus ciprofloxacin had the lowest modified osteomyelitis scores, abscess formation, and bacterial burden on the implant among all groups (P < 0.05). Thus, local treatment with ADSCs plus an antibiotic has an antimicrobial effect in implant-related infection and decrease abscess formation. Thus, our findings indicate that local administration of ADSCs with antibiotics represents a novel treatment strategy for implant-associated osteomyelitis.

Short-course antibiotic regimen compared to conventional antibiotic treatment for gram-positive cocci infective endocarditis: randomized clinical trial (SATIE)

BackgroundMost serious complications of infective endocarditis (IE) appear in the so-called “critical phase” of the disease, which represents the first days after diagnosis. The majority of patients overcoming the acute phase has a favorable outcome, yet they remain hospitalized for a long period of time mainly to complete antibiotic therapy. The major hypothesis of this trial is that in patients with clinically stable IE and adequate response to antibiotic treatment, without signs of persistent infection, periannular complications or metastatic foci, a shorter antibiotic time period would be as efficient and safe as the classic 4 to 6 weeks antibiotic regimen.MethodsMulticenter, prospective, randomized, controlled open-label, phase IV clinical trial with a non-inferiority design to evaluate the efficacy of a short course (2 weeks) of parenteral antibiotic therapy compared with conventional antibiotic therapy (4–6 weeks).Sample: patients with IE caused by gram-positive cocci, having received at least 10 days of conventional antibiotic treatment, and at least 7 days after surgery when indicated, without clinical, analytical, microbiological or echocardiographic signs of persistent infection. Estimated sample size: 298 patients. Intervention: Control group: standard duration antibiotic therapy, (4 to 6 weeks) according to ESC guidelines recommendations. Experimental group: short-course antibiotic therapy for 2 weeks. The incidence of the primary composite endpoint of all-cause mortality, unplanned cardiac surgery, symptomatic embolisms and relapses within 6 months after the inclusion in the study will be prospectively registered and compared.ConclusionsSATIE will investigate whether a two weeks short-course of intravenous antibiotics in patients with IE caused by gram-positive cocci, without signs of persistent infection, is not inferior in safety and efficacy to conventional antibiotic treatment (4–6 weeks).Trial registrationClinicalTrials.gov Identifier: NCT04222257 (January 7, 2020).EudraCT 2019–003358-10.

Identification of a novel phage targeting methicillin-resistant Staphylococcus aureus In vitro and In vivo

IntroductionStaphylococcus aureus is a common human pathogen that causes various diseases including infections on the skin, in the bloodstream and the lower respiratory tracts. The emergence of methicillin-resistant S. aureus (MRSA) made the treatment of the bacterial infection more difficult, calling for development of new therapeutics. Compared with conventional antibiotic therapy, phage therapy offers a promising alternative to combat infections caused by MRSA. ResultsHere we showed that phage VB_SauS_SH-St 15644 isolated from sewage inhibited MRSA isolates in vitro and in the murine skin infection model. Phage VB_SauS_SH-St 15644 belongs to Siphoviridae. The genome of the phage is a linear, 45,111 bp double-stranded DNA with GC content of 33.35%. Among the 37 clinical MRSA isolates tested, 12 (32%) were lysed by the phage in vitro. The phage was relatively stable at temperatures up to 40 °C or between pH 6 and 9. However, the phage was sensitive to UV light. 80% of the phage was approximately adsorbed to the host MRSA isolate in 4 min. The one-step growth curve showed that the latent period was about 12 min followed by the growth period (about 9 min). The burst size was estimated at 13 PFU per infected cell. Furthermore, in a murine skin infection model, the phage significantly inhibited MRSA infection. ConclusionsOur study suggested that phage VB_SauS_SH-St 15644 has a potential to inhibit MRSA skin infection.

Chronic rhinosinusitis disease control as a metric for guiding treatment.

The assessment of Chronic Rhinosinusitis, like any other disease, may involve multiple possible disease manifestations, including subjective patient-reported outcomes, objective disease (e.g. endoscopy or radiographic), and physician-driven (e.g. need for systemic medications). Disease control is often used as a global metric of disease burden and represents the extent to which disease manifestations are within an acceptable range. Achieving control is an important treatment goal.

Dexamethasone along with ciprofloxacin modulates S. aureus induced microglial inflammation via glucocorticoid (GC)-GC receptor-mediated pathway

Microglial inflammation is the hallmark of S. aureus induced brain abscesses. Conventional antibiotic therapy could not regulate inflammation and the use of steroids in CNS infection remained controversial. To address this issue the effect of dexamethasone along with ciprofloxacin on microglial inflammation has been attempted both in glucocorticoid receptor (GR) opened and blocked condition. We have investigated the effects of ciprofloxacin (0.24 μg/ml, pre-treatment) and dexamethasone (150 nM, pre-treatment) in combination with murine microglia infected with S. aureus for 30, 60 and 90 min by either keeping GR opened or blocked with GR antagonist RU486. Alterations in cellular motility, intracellular killing assay, free radical production, antioxidant enzyme activities, corticosterone, and cytokine levels were determined. The expressions of TLR-2, GR, and other inflammatory markers were determined in terms of this combinatorial treatment. Combination treatment significantly (p < 0.05) reduced the bacterial burden of microglia only when GR remained open and effectively suppressed S. aureus induced oxidative stress by augmenting SOD and catalase enzyme activity and suppressing other pro-inflammatory markers at 90 min. Arginase activity, a critical determinant of microglial polarization was found to be higher after treatment at 60 and 90 min. This situation was reversed when this combination treatment was applied by keeping GR blocked using GR antagonist RU486. Therefore, it can be concluded that combination treatment of ciprofloxacin and dexamethasone could regulate S. aureus induced microglial activation, in the presence of functional GR via utilizing glucocorticoid (GC)-GR pathway and ultimately confers protection to the host from brain inflammation.

Cerebral phaeohyphomycosis due to Cladophialophora bantiana in an immunocompetent individual: A case report and brief review of literature

Background and Purpose: Fungal infections of the central nervous system (CNS) are life-threatening conditions that are frequently misdiagnosed with bacterial and viral CNS infections. Cerebral phaeohyphomycosis is a cerebral infection caused by dematiaceous fungi, especially Cladophialophora bantiana. Very few cases of fungal CNS infection have been reported across the world. High clinical suspicion should be cast for the patients with brain abscess that do not respond to conventional antibiotic therapy.Case report: We report a case of a 21-year-old male presenting with headache, seizures and weakness in the limbs. Radiological examination revealed multiple brain abscesses. After surgical excision and laboratory evaluation, it was found to be caused by C. bantiana. The patient’s outcome was good with surgical excision and voriconazole therapy.Conclusion: Brain abscess caused by C. bantiana is on rise, especially in immunocompromised groups. Thus, high clinical suspicion, accurate diagnosis and management are the fundamentals for good prognosis.

Essential Oils of Aromatic Plants with Antibacterial, Anti-Biofilm and Anti-Quorum Sensing Activities against Pathogenic Bacteria.

Both the ability of bacteria to form biofilms and communicate through quorum sensing allows them to develop different survival or virulence traits that lead to increased bacterial resistance against conventional antibiotic therapy. Here, seventeen essential oils (EOs) were investigated for the antimicrobial, antibiofilm, and anti-quorum sensing activities on Escherichia. coli O157:H7, Escherichia coli O33, and Staphylococcus epidermidis ATCC 12228. All essential oils were isolated from plant material by using hydrodistillation and analyzed by GC-MS. The antimicrobial activity was performed by using the microdilution technique. Subinhibitory concentrations of each EO were assayed for biofilm inhibition in both bacterial strains. Quantification of violacein in Chromobacterium violaceum CV026 was performed for the anti-quorum sensing activity. The cytotoxicity activity of the EOs was evaluated on Vero cell line by using MTT method. Thymol-carvacrol-chemotype (I and II) oils from Lippia origanoides and Thymus vulgaris oil exhibited the higher antimicrobial activity with MIC values of 0.37–0.75 mg/mL. In addition, these EOs strongly inhibited the biofilm formation and violacein (QS) production in a concentration-dependent manner, highlighting thymol-carvacrol-chemotype (II) oil as the best candidate for further studies in antibiotic design and development against bacterial resistance.

Role of antibiotics in elective clean surgeries: limiting its use to single shot preoperative dose

Background: Conventional antibiotic therapy during operation not only increases the financial burden on patient, not only increases chances of adverse reactions among them but also not effective in reducing the infection rate after surgery. Single dose prophylactic antibiotic or maximum 24 hours dosing during or before surgery was found to be equally effective. Objective was the to study utility of single shot antibiotic prophylaxis in patients undergoing surgeryMethods: This prospective study includes 100 clean elective surgical cases randomized to groups of 50 each. Single dose prophylactic antibiotic was given to cases in the study group and conventional antibiotic therapy was given to cases in the control group. Study group cases received Injection Ceftriaxone in the dose of 2 gm intravenously. This was given at induction or half an hour before the incision was given. Second dose was given if there was delay in starting the surgery for more than three hours. Dose of the antibiotic was adjusted for children, underweight and obese persons. For cases in the control group. Injection ceftriaxone 1 gm was given intravenously twice a day for three days. Surgical site infection incidence was recorded.Results: Both the groups were comparable for age, sex, diagnosis and hence the type of surgery performed. The incidence of fever, redness, swelling and wound discharge which are the signs of surgical site infection after surgery was not found to be statistically significantly different. Management protocol was also not significantly different after the surgery.Conclusions: Single shot antibiotic before surgery is equally effective in reducing the incidence of surgical site infections (SSIs) compared to conventional antibiotic therapy.

Evaluation of antibacterial and enhancement of antibiotic action by the flavonoid kaempferol 7-O-β-D-(6″-O-cumaroyl)-glucopyranoside isolated from Croton piauhiensis müll

There has been a rapid increase in the incidence and prevalence of opportunistic bacterial infections. Inappropriate use of current antibiotics has continuously contributed to the emergence of resistance to conventional antibiotic therapy. Therefore, the search for natural molecules that are able to combat infections is of great public interest, and many of these compounds with antimicrobial properties can be obtained from phytochemical studies of medicinal plants. In this context, this study reports the isolation and characterization of the flavonoid, kaempferol 7-O-β-D-(6″-O-cumaroyl)-glucopyranoside, from Croton piauhiensis leaves. Additionally, the intrinsic antimicrobial action of the compound and its enhancement against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus strains were assessed. The minimum inhibitory concentration (MIC) of the compound was determined using broth microdilution assays. To evaluate the modulatory effect of the flavonoid, the MIC of antibiotics amikacin and gentamicin, belonging to the class aminoglycosides was assessed, with and without the compound in sterile microplates. The results of intrinsic antibacterial activity tests revealed that the compound had no antibacterial activity against strains tested at concentrations <1024 μg/mL. The combination of the flavonoid at a concentration of 128 μg/mL with gentamicin presented synergistic effects against S. aureus 10 and E. coli 06, and also reduced the MIC from 16 μg/mL to 4 μg/mL and 8 μg/mL, respectively. Amikacin also showed synergistic effects against S. aureus 10 and E. coli 06. We also observed reduced MIC for both, from 128 μg/mL to 32 μg/mL; however, antagonism for P. aeruginosa increased the MIC from 16 μg/mL to 64 μg/mL. The combination of the flavonoid with the aminoglycosides may be an alternative to potentiate the expected results in treatment against S. aureus and E. coli, since their association leads to a synergistic effect, reducing the MIC of these drugs and decreasing the dose necessary for therapeutic success.

The in vitro Photoinactivation of Helicobacter pylori by a Novel LED-Based Device.

The rise of antibiotic resistance is the main cause for the failure of conventional antibiotic therapy of Helicobacter pylori infection, which is often associated with severe gastric diseases, including gastric cancer. In the last years, alternative non-pharmacological approaches have been considered in the treatment of H. pylori infection. Among these, antimicrobial PhotoDynamic Therapy (aPDT), a light-based treatment able to photoinactivate a wide range of bacteria, viruses, fungal and protozoan parasites, could represent a promising therapeutic strategy. In the case of H. pylori, aPDT can exploit photoactive endogenous porphyrins, such as protoporphyrin IX and coproporphyrin I and III, to induce photokilling, without any other exogenous photosensitizers. With the aim of developing an ingestible LED-based robotic pill for minimally invasive intragastric treatment of H. pylori infection, it is crucial to determine the best illumination parameters to activate the endogenous photosensitizers. In this study the photokilling effect on H. pylori has been evaluated by using a novel LED-based device, designed for testing the appropriate LEDs for the pill and suitable to perform in vitro irradiation experiments. Exposure to visible light induced bacterial photokilling most effectively at 405 nm and 460 nm. Sub-lethal light dose at 405 nm caused morphological changes on bacterial surface indicating the cell wall as one of the main targets of photodamage. For the first time endogenous photosensitizing molecules other than porphyrins, such as flavins, have been suggested to be involved in the 460 nm H. pylori photoinactivation.