Effectiveness of cephalosporins in hydrolysis and inhibition of Staphylococcus aureus and Escherichia coli biofilms.

IMPORTANCE: Staphylococcus aureus and Escherichia coli contribute to global health challenges by forming biofilms, a key virulence element implicated in the pathogenesis of several infections. OBJECTIVE: The study examined the efficacy of various generations of cephalosporins against biofilms developed by pathogenic S. aureus and E. coli. METHODS: The development of biofilms by both bacteria was assessed using petri-plate and microplate methods. Biofilm hydrolysis and inhibition were tested using first to fourth generations of cephalosporins, and the effects were analyzed by crystal violet staining and phase contrast microscopy. RESULTS: Both bacterial strains exhibited well-developed biofilms in petri-plate and microplate assays. Cefradine (first generation) showed 76.78% hydrolysis of S. aureus biofilm, while significant hydrolysis (59.86%) of E. coli biofilm was observed by cefipime (fourth generation). Similarly, cefuroxime, cefadroxil, cefepime, and cefradine caused 78.8%, 71.63%, 70.63%, and 70.51% inhibition of the S. aureus biofilms, respectively. In the case of E. coli, maximum biofilm inhibition (66.47%) was again shown by cefepime. All generations of cephalosporins were more effective against S. aureus than E. coli, which was confirmed by phase contrast microscopy. CONCLUSIONS AND RELEVANCE: Cephalosporins exhibit dual capabilities of hydrolyzing and inhibiting S. aureus and E. coli biofilms. First-generation cephalosporins exhibited the highest inhibitory activity against S. aureus, while the third and fourth generations significantly inhibited E. coli biofilms. This study highlights the importance of tailored antibiotic strategies based on the biofilm characteristics of specific bacterial strains.

Chemical composition and antimicrobial study of Crossobamon orientalis body oil.

Geckos and their products have been used in Asian traditional medicine. Medicinal properties of desert-dwelling Gecko species, Crossobamon orientalis remain unexplored. In this study, natural bioactive macromolecules present in oil extracted from C. orientalis (COO) and their biological activities were evaluated. Chemical constitution of COO was explored by using gas chromatography mass spectrometry. Antioxidant, antiviral, and antibacterial activities of COO extracts were assessed using various assays, including DPPH free-radical-protocol, HET-CAM method, in ovo-antiviral technique, and disc-diffusion method. GC-MS study reported 40 different compounds in COO. n-hexane and methanol extracts of COO demonstrated highest DPPH radical inhibition, with values of 70 and 63.3%, respectively. Extracts of COO in solvents, namely 1-butanol, methanol, diethyl ether, and n-hexane significantly inhibited the proliferation of four pathogenic viruses. Maximum zone of inhibition was observed for Escherichia coli (13.65 ± 0.57 mm). These findings suggest that COO possesses potent antioxidant and antimicrobial properties against viral and bacterial strains, thanks to its biologically active components having no side effects. Further studies are essential to isolate and identify individual bioactive compounds present in COO and to investigate their potential as therapeutic agents.

Synthesis, characterization, molecular docking and biological evaluation of Schiff Base derivatives of cefpodoxime.

Synthesis of new Cefpodoxime derivatives via Schiff Bases mechanism and the efficiency of their antimicrobial and antiviral activities were addressed. They were analyzed for structural validation by using spectroscopic techniques using FTIR, 1HNMR, and 13CNMR. Molecular docking against IBV Virus papain-like protease (PLPro) was done with Auto dock tools against compounds having excellent IC50 values against IBV (Corona Class) virus. All derivatives showed strong zone of inhibition ranges from (55 ± 2.0 to 70 ± 0.8 mm) against E. coli. Compounds 1,2,4 and 6 derivatives showed remarkable activity against Stenotrophomonas maltophilia and Serratia marcescens. But For most the newly synthesized derivatives C 1 (64 ± 1.60), C 3 (32 ± 0.80), and C 8 (64 ± 1.60) showed potential IC50 values against two variants of Corona class viruses i.e. Avian Influenza (H9) and Avian corona (IBV) viruses. The current study revealed that newly synthesized Schiff Bases possessed strong anti-viral potential. Further studies may make a breakthrough in medical sciences to tackle latest challenges such as Corona Virus Diseases.

Antimicrobial, antioxidant, antiviral activity, and gas chromatographic analysis of Varanus griseus oil extracts.

There is an urgent need to develop natural antimicrobials for the control of rapidly mutating drug-resistant bacteria and poultry viruses. Five extracts were prepared using diethyl ether, ethyl acetate, methanol, 1-butanol and n-hexane from abdominal fats of Varanus griseus locally known as Indian desert monitor. Antibacterial, antioxidant and antiviral activities from oil extracts were done through disc diffusion method, stable 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay and in ovo antiviral assay, respectively. The gas chromatography mass spectrometry (GC-MS) analyses were used to determine principal active compounds and chemical profile of each oil extract. n-Hexane extract showed clear zones of inhibition (ZOI) against Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae (12 ± 0.5 mm, 9 ± 0.5 mm, and 9 ± 0.5 mm) while diethyl ether extract exhibited significant antibacterial activity (11 ± 0.5 mm) against Proteus vulgaris only. In case of drug-resistant strains, methanol extract was active (6 ± 0.5 mm) against Staphylococcus aureus, whereas n-hexane extract has shown ZOI 11 ± 0.5 mm against P. aeruginosa. Range of percentage scavenging activity of V. griseus oil extracts from DPPH free radical assay was 34.9-70.7%. For antiviral potential, growth of new castle disease virus (NDV) was effectively inhibited by all five extracts (HA titer = 0-4). The highest antiviral activity against avian influenza virus (H9N2) was observed from methanol, diethyl ether and 1-Butanol oil extracts with HA titers of 2, 2 and 0, respectively. Methanol, diethyl ether, 1-butanol and n-hexane oil extracts produced best hemagglutination assay (HA) titer values (0, 0, 4 and 0) against infectious bronchitis virus (IBV). Ethyl acetate and 1-Butanol extract exhibited good antiviral potential against infectious bursal disease virus (IBDV) with indirect hemagglutination assay (IHA) titers of 8 and 4, respectively. Main classes of identified compounds through gas chromatography were aldehydes, fatty acids, phenols and esters. GC-MS identified 11 bioactive compounds in V. griseus oil extracts. It is summarized that V. griseus oil has strong antioxidant activity and good antimicrobial potential because of its bioactive compounds.

Pyridine Scaffolds, Phenols and Derivatives of Azo Moiety: Current Therapeutic Perspectives.

Synthetic heterocyclic compounds have incredible potential against different diseases; pyridines, phenolic compounds and the derivatives of azo moiety have shown excellent antimicrobial, antiviral, antidiabetic, anti-melanogenic, anti-ulcer, anticancer, anti-mycobacterial, anti-inflammatory, DNA binding and chemosensing activities. In the present review, the above-mentioned activities of the nitrogen-containing heterocyclic compounds (pyridines), hydroxyl (phenols) and azo derivatives are discussed with reference to the minimum inhibitory concentration and structure-activity relationship, which clearly indicate that the presence of nitrogen in the phenyl ring; in addition, the hydroxyl substituent and the incorporation of a diazo group is crucial for the improved efficacies of the compounds in probing different diseases. The comparison was made with the reported drugs and new synthetic derivatives that showed recent therapeutic perspectives made in the last five years.

Diaryl azo derivatives as anti-diabetic and antimicrobial agents: synthesis, in vitro, kinetic and docking studies.

In the present study, a series of azo derivatives (TR-1 to TR-9) have been synthesised via the diazo-coupling approach between substituted aromatic amines with phenol or naphthol derivatives. The compounds were evaluated for their therapeutic applications against alpha-glucosidase (anti-diabetic) and pathogenic bacterial strains E. coli (gram-negative), S. aureus (gram-positive), S. aureus (gram-positive) drug-resistant strain, P. aeruginosa (gram-negative), P. aeruginosa (gram-negative) drug-resistant strain and P. vulgaris (gram-negative). The IC50 (µg/mL) of TR-1 was found to be most effective (15.70 ± 1.3 µg/mL) compared to the reference drug acarbose (21.59 ± 1.5 µg/mL), hence, it was further selected for the kinetic studies in order to illustrate the mechanism of inhibition. The enzyme inhibitory kinetics and mode of binding for the most active inhibitor (TR-1) was performed which showed that the compound is a non-competitive inhibitor and effectively inhibits the target enzyme by binding to its binuclear active site reversibly.

REPORT- Some ethanobotanically important plants from Cholistan area for anti avian influenza virus (AIV) H9N2 screening.

Avian influenza or bird flu is a common problem of domestic and wild birds. Some of its strains are able to cross the species barrier and cause infection in various members of class Mammalia. In view of relatively lesser efficacy of vaccines, antiviral therapies remain the only choice for the sustenance of mammals acquiring this highly devastating infection. This study is based on the evaluation of antiviral potential of methanol extracts of eleven selected Cholistani plants. The methanol extracts were prepared by using dried plants material followed by concentrating in a rotary evaporator and finally air dried before dissolving in nanopure water. The suspension was filter sterilized and subjected to in ovo antiviral assays. The allantoic fluids were harvested and haemagglutinin (HA) titers were determined. Among the eleven plants evaluated all methanol extracts were found effective against AIV H9N2 except S. baryosma extract. The medicinal plants O. compressa, N. procumbens, and S. surattense were found to be more effective than others and they retained HA titers at 0 after challenge. The next in order were extracts of O. esculentum, H. salicornicum and S. fruticosa which kept HA titers at 4, 8 and 16 respectively. The extracts of H. recurvum, P. antidotale, S. icolados and A. aspera were found less effective than above mentioned plant extracts and they kept the HA titers at 32, 64, 128 and 256 respectively. These results led us to conclude that the medicinal plants of Cholistan region are a rich source of antiviral agent(s) against AIV H9N2 and could be a source of cost effective alternate therapeutics.

Evaluation of DNA vaccines encoding M. Tb gene Bfrb and Mpt32 in mice model.

Tuberculosis (TB) is a life threatening infectious disease which is prevalent throughout the world. Mycobacterium bovis based Bacille Calmette-Gue´rin (BCG) is the only vaccine available against TB however, this (single) vaccine is not enough to eradicate it. Furthermore, numbers of researches from different parts of the World have shown its efficacy as variable. Hence other (better) vaccines like DNA vaccines are needed in addition to BCG in order to achieve desired goal of TB eradication. The current study was aimed to develop subunit based DNA vaccines against TB and to check their efficacy. Two constructs Bfrb-pND14 and Mpt32-pND14 were made and used as DNA vaccines. Endotoxin free DNA preparations were made and used in immunization studies. Twenty Balb/c female mice of age eight weeks were used in trial. Two experimental groups each comprising eight animals were used to inoculate Mpt32-pND14 and Bfrb-pND14 vaccines respectively. A group of four animals was used as negative control. Animals were bled through tail periodically and finally through cardiac puncture before euthanization. Antibodies were confirmed through dot blot and Agar Gel Immuno Diffusion test (AGID). All the animals immunized with both vaccines were found positive as tested through dot blot and AGID. The results of this study have indicated that both the M. tb genes have produced strong immune response in mice model through pND14 vector and proved themselves as good subunit based DNA vaccines.

Parasitological, serological and molecular survey of Trypanosoma evansi infection in dromedary camels from Cholistan Desert, Pakistan.

BACKGROUND: Surra, a vector borne disease caused by Trypanosoma (T.) evansi, affects the health, productivity and working capacity of camels. Since clinical signs are not pathognomonic, diagnosis must be confirmed by laboratory methods. This is a first study on the prevalence of surra in Cholistan Desert, Pakistan using a broad variety of diagnostic tests thereby emphasizing it as a risk for the dromedaries of Pakistan. METHODS: In a cross sectional study, 1005 dromedary camels from three districts in the Cholistan Desert were sampled to assess the prevalence of trypanosomosis due to T. evansi by means of parasitological (Giemsa stained thin smear), serological (formol gel test, CATT/T. evansi, ELISA/VSG RoTat 1.2, immune trypanolysis) and molecular tests (TBR1/2 PCR and RoTat 1.2 PCR). Kappa was calculated to assess the degree of agreement between different tests whereas chi-square test along with odds ratios and their 95% confidence intervals were used to study influence of breed, gender, age and locality on disease prevalence. RESULTS: Overall prevalence was 0.7% with Giemsa stained thin smears (GST), 40.1% with formol gel test (FGT), 47.7% with CATT/T. evansi, 44.2% with ELISA/VSG RoTat 1.2, 39.9 % with immune trypanolysis (TL), 31.9 % with TBR1/2 PCR and 30.5% with RoTat1.2 PCR. Based on these results, the Cholistan Desert appears to be a high risk area for surra. According to TL and TBR1/2 PCR, camels at Bahawalpur are approximately two times more likely to be infected than those in Bahawalnagar (OR = 1.8; 95% CI: 1.38-2.42) and Rahim Yar Khan (OR = 1.9; 95% CI: 1.30-2.75). Test agreement of TL was moderate with CATT/T. evansi (k = 0.43; 95% CI: 0.378-0.489) and ELISA/VSG RoTat 1.2 (k = 0.54; 95% CI: 0.489-0.594) and poor with the other tests. Test agreement between TBR1/2 PCR and RoTat1.2 PCR was almost perfect (k = 0.96; 95% CI: 0.950-0.984). We didn't find evidence for the presence of T. evansi type B in the studied population. CONCLUSION: Our study supports using antibody detection tests, rather than parasitological and molecular examination, to assess surra prevalence in camels. It also calls for implementation of measures to control surra in the Cholistan Desert.

Plasma antibody profiles as diagnostic biomarkers for tuberculosis.

Two billion people are infected with Mycobacterium tuberculosis, the etiological agent of tuberculosis (TB), worldwide. Ten million to 20 million of the infected individuals develop disease per year. TB is a treatable disease, provided that it is diagnosed in a timely manner. The current TB diagnostic methods are subjective, inefficient, or not cost-effective. Antibody-based blood tests can be used efficiently and cost-effectively for TB diagnosis. A major challenge is that different TB patients generate antibodies against different antigens. Therefore, a multiplex immunoassay approach is needed. We have developed a multiplex panel of 28 M. tuberculosis antigen-coated microbeads. Plasma samples were obtained from over 300 pulmonary TB patients and healthy controls in a country where TB is endemic, Pakistan. Multiplex data were analyzed using computational tools by multivariate statistics, classification algorithms, and cluster analysis. The results of antibody profile-based detection, using 16 selected antigens, closely correlated with those of the sputum-based diagnostic methods (smear microscopy and culture) practiced in countries where TB is endemic. Multiplex microbead immunoassay had a sensitivity and specificity of approximately 90% and 80%, respectively. These antibody profiles could potentially be useful for the diagnosis of nonpulmonary TB, which accounts for approximately 20% of cases of disease. Since an automated, high-throughput version of this multiplex microbead immunoassay could analyze thousands of samples per day, it may be useful for the diagnosis of TB in millions of patients worldwide.

Passive immunization against highly pathogenic Avian Influenza Virus (AIV) strain H7N3 with antiserum generated from viral polypeptides protect poultry birds from lethal viral infection.

Our studies were aimed at developing a vaccination strategy that could provide protection against highly pathogenic avian influenza virus (AIV), H7N3 or its variants outbreaks. A purified viral stock of highly pathogenic H7N3 isolate was lysed to isolate viral proteins by electrophresing on 12% sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), followed by their elution from gel through trituration in phosphate buffered saline (PBS). Overall, five isolated viral polypeptides/proteins upon characterization were used to prepare hyperimmune monovalent serum against respective polypeptides independently and a mixture of all five in poultry birds, and specificity confirmation of each antiserum through dot blot and Western blotting. Antiserum generated from various group birds was pooled and evaluated in 2-week old broiler chicken, for its protection against viral challenge. To evaluate in-vivo protection of each antiserum against viral challenges, six groups of 2-week old broiler chicken were injected with antiserum and a seventh control group received normal saline. Each group was exposed to purified highly pathogenic AIV H7N3 strain at a dose 10(5) embryo lethal dose (ELD(50)). We observed that nucleoprotein (NP) antiserum significantly protected birds from viral infection induced morbidity, mortality and lowered viral shedding compared with antiserum from individual viral proteins or mixed polypeptides/proteins inclusive of NP component. The capability of individual viral polypeptide specific antisera to protect against viral challenges in decreasing order was nucleoprotein (NP) > hemagglutinin (HA) > neuraminidase (NA) > viral proteins mix > viral polymerase (PM) > non-structural proteins (NS). Our data provide proof of concept for potential utilization of passive immunization in protecting poultry industry during infection outbreaks. Furthermore conserved nature of avian NP makes it an ideal candidate to produce antiserum protective against viral infection.