Gram-positive and Gram-negative Cells

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Gram-Positive and Gram-Negative Bacteria Synergize with Oxidants to Release CXCL8 from Innate Immune Cells

Gram-Positive and Gram-Negative Bacteria Synergize with Oxidants to Release CXCL8 from Innate Immune Cells

In an attempt to extrapolate our obser- vations in vitro to a human model of oxi- dant stress, we studied response in the blood of healthy smokers, where oxidant load is significantly increased compared with that of nonsmokers (29). It has been well recognized for several years that smoking creates an oxidant stress detect- able in the blood. The level of oxidant stress is proportional to the amount of cigarettes smoked (30). Whereas oxidant markers in the blood of regular smokers are raised throughout the day, they in- crease further immediately after smoking (31). In direct corroboration of our in vitro data, we found that that the blood of smokers was more sensitive to activa- tion by TLR ligands than the blood of nonsmokers. We then went on to com- pare responses of monocytes isolated from the blood of smokers and non- smokers. Again we found that mono- cytes from smokers were exquisitely sen- sitive to bacteria and PAMPs compared with cells from nonsmokers. Our obser- vations with monocytes show that oxi- dant priming persists, at least for the du- ration of our experiment, once the oxidant environment (in this case the blood) is removed from the cells. These observations demonstrate the principle of oxidants synergizing with PAMPs for

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Type IV secretion in Gram negative and Gram positive bacteria

Type IV secretion in Gram negative and Gram positive bacteria

further highlight the biological diversity of this secretion superfamily. This has been exemplified by discovery that Xanthomonas citri employs a T4SS to kill competing bacteria in the close vicinity in a contact-dependent manner, reminiscent of the type VI secretion killing systems (Souza et al., 2015). An update of this system was presented at a T4SS conference held last December 2016 in Schloss Hirschberg, Germany (www.t4ss-conference.de). This T4SS translocates effectors bearing C-terminal translocation signals, whose bacteriolytic activities degrade peptidoglycan in target cells, but in the donor cell can be neutralized by the synthesis of cognate immunity proteins (Souza et al., 2015; 2016). Intriguingly, more than one thousand Xanthomonas T4SS effectors showing only very limited homology to each other or other proteins were found in protein databases (Souza et al., 2016). This T4SS appears to be widely dispersed among Xanthomonas and related species, making this a possible paradigm for an emerging new family of T4SS-killing machines in bacteria.

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Activity of siderophores against drug-resistant Gram-positive and Gram-negative bacteria

Activity of siderophores against drug-resistant Gram-positive and Gram-negative bacteria

Most nosocomial infections are caused by Gram-positive methicillin-resistant Staphy- lococcus aureus (MRSA) and Gram-negative metallo- β -lactamase (MBL)-producing bacteria such as Pseudomonas aeruginosa and Acinetobacter baumannii. Emergence of drug resistance in such pathogens has made treatment difficult, making explora- tion of new therapeutic options imperative. As iron is an essential cofactor of many important biochemical pathways for all cells, one possible strategy would be to impose an iron-deficient environment on these pathogens.

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Solid Phase Chemical Synthesis and Structure - Activity Study of Brevinin - 2R and Analogues as Antimicrobial Peptides

Solid Phase Chemical Synthesis and Structure - Activity Study of Brevinin - 2R and Analogues as Antimicrobial Peptides

So far, it has been reported that structural parameters such as net positive charge, hydrophobicity, peptide helicity, hydrophobic moment, and the size (angle) of hydrophobic / hydrophilic domain influence the activity and selectivity of membrane-active peptides (16- 23). Among these parameters, net positive charge, helicity, and hydrophobicity appear to be the most fundamental factors for activity and selectivity (17, 20). Besides, it is generally believed that the change of net positive charge and hydrophobicity, which result in the change of α-helical structure, is an important factor for the specificity toward neutrally charged membrane (23-26). The Brevinin-2R is a novel peptide that unlike other Brevinins showed no significant hemolytic activity. In this study, to investigate the biological implications of Brevinin-2R and its structure-activity relationship, we synthesized the analogues of Brevinin-2R (BR-D and BR-C) with net positive charge and different α-helical structure and hydrophobicity similar to that of Brevinin-2R. Based on our previous investigation showing the Brevinin-2R impacts on different cancer cells (Patent No.: WO / 2006 / 128289), we decided to study the effect of α-helical structure and hydrophobicity on the specificity against bacteria. Accordingly, we synthesized BR-D and BR-C analogues. Based upon our findings, increase of α-helical structure and hydrophobicity enhanced antimicrobial activity on Gram-positive and Gram-negative bacteria also on cancer cells (data not shown) than BR-D and BR-C analogues.

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Enhancement of HIV 1 infection and intestinal CD4+ T cell depletion ex vivo by gut microbes altered during chronic HIV 1 infection

Enhancement of HIV 1 infection and intestinal CD4+ T cell depletion ex vivo by gut microbes altered during chronic HIV 1 infection

Results: The majority of HAMB increased HIV-1 infection and depletion of LP CD4 T cells, but gram-negative HAMB enhanced CD4 T cell infection to a greater degree than gram-positive HAMB. Most gram-negative HAMB enhanced T cell infection to levels similar to that induced by gram-negative E. coli despite lower induction of T cell activation and proliferation by HAMB. Both gram-negative HAMB and E. coli significantly increased expression of HIV-1 co-receptor CCR5 on LP CD4 T cells. Lipopolysaccharide, a gram-negative bacteria cell wall component, up-regulated CCR5 expression on LP CD4 T cells whereas gram-positive cell wall lipoteichoic acid did not. Upregulation of CCR5 by gram- negative HAMB was largely abrogated in CD4 T cell-enriched cultures suggesting an indirect mode of stimulation. Conclusions: Gram-negative commensal bacteria that are altered in abundance in the colonic mucosa of HIV-1 infected individuals have the capacity to enhance CCR5-tropic HIV-1 productive infection and depletion of LP CD4 T cells in vitro. Enhanced infection appears to be primarily mediated indirectly through increased expression of CCR5 on LP CD4 T cells without concomitant large scale T cell activation. This represents a novel mechanism potentially linking intestinal dysbiosis to HIV-1 mucosal pathogenesis.

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Antibacterial activity of trimetal (CuZnFe) oxide nanoparticles

Antibacterial activity of trimetal (CuZnFe) oxide nanoparticles

The results of CFU measurements indicated that the action of CuZnFe oxide NPs on E. coli was non-permanent, by showing recovery of the treated cells (Figure 8). The CFU results also indicated that the CuZnFe oxide NPs had a similar effect on E. coli and E. faecalis and an intermediate effect compared to the effects by the CuO or ZnO NPs. Trimetal (CuZnFe) oxide NPs affected biofilm formation to a lesser degree than did individual ZnO and CuO NPs. This indicates that the reduction in biofilm formation was not a result of cell loss but of the NP effect. Reduced biofilm formation with exposure to CuO and ZnO correlated with cell death and reduced CFU count for both E. faecalis and E. coli, but this was not the case with CuZnFe oxide NPs. The reduced disruption of biofilm formation by CuZnFe oxide NPs might result from the disruption in quorum sensing rather than from the effect of NPs. Quorum sensing has been established as an important factor in biofilm formation in both gram-positive and gram-negative bacteria. 38–41 However, more investigation

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CSF inflammatory markers differ in gram-positive versus gram-negative shunt infections

CSF inflammatory markers differ in gram-positive versus gram-negative shunt infections

Identifying biomarkers in the CSF or serum of patients with shunt infection may improve our ability to diagnose CSF shunt infections. Biomarkers are distinct biochem- ical, genetic, or molecular substances that characterize infection [20, 21]. There are a few small studies that have evaluated the ability of CSF chemokines and cyto- kines to characterize different bacterial and viral menin- gitis. Many studies have examined the utility of using chemokines and cytokines for the diagnosis of meningi- tis. In early meningeal infection, the pro-inflammatory cytokines interleukin (IL)-8, IL-1, tumor necrosis factor alpha (TNF-α), and IL-6 have been shown to be elevated [22–25]. These mediators are released from CNS resi- dent cells and function to recruit neutrophils and per- petuate the inflammatory response [26, 27]. Once monocytes are recruited, the anti-inflammatory cytokine IL-10 and IL-1β dampen inflammation by inhibiting pro- duction of pro-inflammatory cytokines [28].

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Assessment of Antimicrobial Activity of Developed Banana Fiber Fabric

Assessment of Antimicrobial Activity of Developed Banana Fiber Fabric

Therefore, the banana fabrics were finished with commercially available antimicrobial agent AB1000 which showed significant resistance against both Gram positive (18mm) and Gram negative (21mm) bacteria and mixed fungal spores. The results of AATCC 147 also showed that the fabric had good antibacterial effect of 15mm against E. coli and 17mm against S. aureus, similarly AATCC 100 method showed approximately 98% reduction in case of both the strains. The soil burial test showed that the fabric when finished with AB1000 has good strength in the fibers even after 9 days under the soil. This revealed the finished fabric had an efficient antimicrobial property.

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SYNTHESIS AND EVALUATION OF NOVEL-3-AMINO-2-ARYL [1,2,4] TRIAZOLO [5,1-b] QUINOZOLIN-9 (3H)-ONES OF BIOLOGICAL INTEREST

SYNTHESIS AND EVALUATION OF NOVEL-3-AMINO-2-ARYL [1,2,4] TRIAZOLO [5,1-b] QUINOZOLIN-9 (3H)-ONES OF BIOLOGICAL INTEREST

Compounds IVe, IVf, IVh, IVi and IVj at (50 g/ml) and IVa, IVb, IVc, IVd, IVf IVh, IVi , IVj (100 g/ml) showed promising antibacterial activity against Pseudomonas gram (-ve) bacteria compare to standard drug Cetazolin sodium.Compounds IVe, IVf, IVg, IVh, IVi at (50 g/ml) and IVc, IVd at (100 g/ml) showed moderate activity against Staphylococcus aureus gram (+ve) bacteria compare to standard drug procaine penicillin. The compounds IVa, IVb, IVc, IVd, IVg, IVh, IVi at (50 g/ml) and IVb, IVe (100 g/ml) being same has been found exhibit relatively by more in their inhibitory action against Escherichia colli gram (-ve) bacteria, compare to standard drug streptomycin.

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Isolation and identification of microbial and fungal flora from female hair samples in Riyadh Saudi Arabia

Isolation and identification of microbial and fungal flora from female hair samples in Riyadh Saudi Arabia

fungi and also bacteria. The present study was performed to determine the prevalence of keratinophilic fungi and bacteria from hair samples of femalesfrom November 2016 to April 2017. A total of 50 human hair samples were examinedusing hair-baiting techniques for isolation. After the incubation period, the number of colony forming unit was counted. The microorganisms were identified based on the colony morphology from culture and microscopic features. After purification, each representative colony was gram-stained and examined for cell morphology and gram reaction under a light microscope. Fungal isolates included were Aspergillus niger, Aspergillus flavus, Penicilliumspp, Alternaria alternata, Chrysosporium keratinophilum. Cladosporium cladosporioides and Trichosporon mucoides. Isolated bacterial species included gram positive bacteria such as Leuconostoc mesenteroidess spcremoris, Kocuriarosea, Staphylococcus haemolyticus, and the gram negative bacteria Kocurikristinae, Stenotrophomonas maltophilia, and Micrococcus luteu/ lylae. Human hair samples from females studied were found have several fungal and bacterial isolates, some of which can cause some serious disease in humans. Health authorities need to heighten up their health information campaigns that will include not only prevention and treatment of serious illnesses but also body hygiene.

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THE COMMON BACTERIAL CAUSES OF VAGINAL INFECTION IN ERBIL CITY

THE COMMON BACTERIAL CAUSES OF VAGINAL INFECTION IN ERBIL CITY

Background and objectives: Vaginitis is a term used to describe infectious diseases and other inflammatory conditions affecting the vaginal mucosa, bacterial vaginitis appears to be associated with pelvic inflammatory disease, infectious complications after abortion or gynecological invasive procedures. The study aimed to isolate the common bacterial causes of vaginal infection and to determine the antibiotic profile of each bacteria isolated in high vaginal swab. Methods and materials: High vaginal swabs were collected from two hundred (200) women patients with vaginal infection symptoms who attend the Rizgary Hospital, Maternity Teaching Hospital and PAR Hospital in Erbil city in the period from (September 2016-February 2017). All vaginal swabs taken from married non-pregnant patients. The age of these patients ranged between (18-55) years, Swabs were transported to the lab, the samples were directly examined and specimens where inoculated to several culture media after incubation overnight at 37°C, the bacterial colonies were identified on the following medias: Muller Hinton Agar, MacConkey agar, Blood agar plate, Chocolate agar and antibacterial susceptibility profile determined for each bacterium either by VITEK® 2 PC or by disk method. Results: gram positive isolated from (58%) while gram negative isolated from (42%) of patients complaining from vaginitis, the number and percentage of isolated bacteria was as follow: Escherichia coli, Streptococcus agalactiae 28(22.5%), Klebsiella pneumoniae, Staphylococcus haemolyticus in16(12.9%), Staphylococcus aureus, Enterococcus faecalis in 12(9.8%) while Neisseria gonorrhoeae, Serratia marcescens and Staphylococcus saprophyticus in 4(3.3%) and the positive bacterial growth and the Antibiotic susceptibility profile showed that most of the pathogens were resistant to more than one Antibiotics. Conclusions: The incidence of gram positive was higher than gram negative bacteria and and the result of bacterial culture and the most of gram positive and gram negative were resistant to Ampicillin, Amoxicillin and most of these pathogens were sensitive to Amikacin, Gentamicin and Tetracycline.

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Prognostic factors and monomicrobial necrotizing fasciitis: gram positive versus gram negative pathogens

Prognostic factors and monomicrobial necrotizing fasciitis: gram positive versus gram negative pathogens

[7,8,20]. In the present study, the overall mortality rate was 15.2% whereas the limb amputation rate was 10.9% under the treatment protocol employed. No significant difference in mortality rate was observed between patients with infections due to gram-positive pathogens and those with infections due to gram-negative patho- gens (9.09% versus 17.14%, p = 1.000). Antibiotic thera- pies were chosen based on clinical presentation at the ED: a third-generation cephalosporin plus tetracycline when a gram-negative pathogen such as Vibrio or Aero- monas was suspected, and oxacillin plus gentamicin when a gram-positive pathogen was suspected [21-24]. It is well-established that immediate wide excision of all necrotic soft tissue and appropriate antibiotic therapy are essential for a positive clinical outcome. In the cur- rent study, hyperbaric oxygen therapy was included in

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An optimized staining technique for the detection of Gram positive and Gram negative bacteria within tissue

An optimized staining technique for the detection of Gram positive and Gram negative bacteria within tissue

Gram stain is the most common staining technique used diagnostically within both the clinical setting and in research laboratories to differentiate between Gram posi- tive and Gram negative microorganisms in various types of tissues [17, 26]. As seen in Fig. 2, in vitro Gram stain of S. aureus and P. aeruginosa readily differentiates between these two classes of organisms in  vitro. Moreover this distinction is still evident when applied to both large aggregates and individual detached bacteria within bio- films despite the presence of structures within the poly- meric matrix such as carbohydrates, lipids and proteins that have the potential to interfere with the stain [32]. For a more detailed classification of the bacterial strains used in this study, antibodies specific for S. aureus or P. aeruginosa (i.e., immunocytochemistry) were used as a validation tool. As seen in Fig. 2c, d, the shape of bacilli and cocci bacteria are illustrated, demonstrating success- ful identification of P. aeruginosa strains and S. aureus, respectively.

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ETIOLOGICAL LANDSCAPE OF MICROORGANISMS CAUSING BLOOD STREAM INFECTIONS: COMMENSAL? OR PATHOGEN?

ETIOLOGICAL LANDSCAPE OF MICROORGANISMS CAUSING BLOOD STREAM INFECTIONS: COMMENSAL? OR PATHOGEN?

The reason for undertaking this study and the selected article title is not merely to make a list of organisms isolated from blood samples but to give a serious thought whether to consider these organisms as pathogen or a commensal. Because, in laboratories where large number of blood samples are processed we are not just getting the samples from immuno compromised or immuno suppressed patients. Also we don’t have the complete history of patients in several cases. So through this, what we suggest is just to process each and every sample that has flagged positive by BacT alert and identify every isolate so that we can proceed to determine their antibiotic sensitivities.

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Synthesis, Spectral Characterization and Antibacterial Activity of Functionalized Hydrazones

Synthesis, Spectral Characterization and Antibacterial Activity of Functionalized Hydrazones

The antibacterial activities of our hydrazone compounds are comparable to with standard drug Streptomycin. Acetoyl hydrazones (APAH and ATAH) compounds show more activity when compared with benzoyl hydrazone(APBH and ATBH) compounds, All the compounds show gradually increasing activity with concentrations towards both gram positive and

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PREVALENCE OF GRAM NEGATIVE AND GRAM POSITIVE PATHOGENIC BACTERIA IN DIFFER ISOLATE OF PATIENTS IN BAGHDAD HOSPITALS

PREVALENCE OF GRAM NEGATIVE AND GRAM POSITIVE PATHOGENIC BACTERIA IN DIFFER ISOLATE OF PATIENTS IN BAGHDAD HOSPITALS

1187 Table (3) reveals the distribution of all samples according to the type of gram stain bacteria with age. It was founded that 58% of the samples have showed gram negative bacterial infection, 37.6% showed gram positive and 4.4% only have shown mixed infections,so distribution of the bacteria were more distribution in second group (36.2%) compare to other groups (< 20 , >40 ) as ( 32.5 , 31.3)% respectively.

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Performances of VITEK 2 Colorimetric Cards for Identification of Gram Positive and Gram Negative Bacteria

Performances of VITEK 2 Colorimetric Cards for Identification of Gram Positive and Gram Negative Bacteria

Of the 249 gram-positive strains tested with both the ID- GPC and GP cards and the 331 gram-negative strains tested with both the ID-GNB and GN cards, 218 (87.5%), 235 (94.4%), 295 (89.1%), and 321 (97%) were correctly identified (to the genus or species level), respectively (Tables 1 and 2). A total of 33 bacteria remained unidentified with the fluorimetric cards, whereas the colorimetric cards did not give an identifi- cation for five strains. Regardless of their origin (combined stock collection and clinical isolates), fermenting gram-nega- tive bacteria were correctly identified with both ID-GN and GN cards (97.2% and 98.7%, respectively). In contrast, non- fermenting gram-negative bacteria were better identified with GN cards (92.1%) than with ID-GN cards (67%). Gram-pos- itive bacteria were better identified with colorimetric cards than with fluorimetric cards. For Streptococcaceae, readings of fluorimetric and colorimetric cards gave 87.9% and 90.9% correct identifications, respectively. For Micrococcaceae, these readings were 87.2% and 98.3%, respectively. Our results ob- tained with gram-negative bacteria were for the most part in agreement with those reported by Funke and Funke-Kissling (3). Testing 511 fermenting and 144 nonfermenting gram-neg- ative bacilli, these authors (3) obtained slightly better results with the GN cards than we did in the present study (99.5% and 98.7%, respectively). Recently, in another study focusing on gram-positive bacteria, Funke and Funke-Kissling (4) obtained correct identification of Streptococcaceae (217 strains) and Mi- crococcaceae (147 strains) for 99.1% and 99.3% of these bac- teria, respectively, whereas the results were 90.9% and 98.3% in our study. It should be noticed that the results reported by Funke and Funke-Kissling (3, 4) appeared better but that the numbers of taxa tested (13, 18, and 12 for Micrococcaceae, Streptococcaceae, and nonfermenting bacilli, respectively) were lower than in our study, except for fermenting bacteria (42 taxa in both studies). In fact, as Funke and Funke-Kissling have previously claimed to have done (3, 4), we have selected rare bacteria isolated in routine practice and some of them, such as S. constellatus or S. gordonii, while infrequently isolated in routine testing, were isolated in large numbers in our study (for

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Retrospective Study on the Association between Maternal Macronutrient Intake and Urogenital Infections during Pregnancy in a Swiss Cohort

Retrospective Study on the Association between Maternal Macronutrient Intake and Urogenital Infections during Pregnancy in a Swiss Cohort

This study examined the association between maternal macronutrient intake and relative macronutrient distribution in maternal diet and vaginal/urinary tract infections during pregnancy. The microorganisms known to be part of the polymicrobial community involved in vaginal and urinary tract infections were studied as separate entities. Significant association was found between excessive fat intake and Gardnerella vaginalis infection. The mechanism behind this association could be based on findings suggesting that fatty acids modulate immune functions and inflammatory status. The mucosal immune system is regulated by the gut- associated lymphoid tissue [26]. Innate immune cells are known to sense lipopolysaccharides (LPS), a pathogen-associated molecular pattern, by the activation of Toll-like receptor (TLR4),

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Real Time PCR for Detection and Differentiation of Gram Positive and Gram Negative Bacteria

Real Time PCR for Detection and Differentiation of Gram Positive and Gram Negative Bacteria

Currently, the early detection of bacterial DNA in the cir- culating blood of critically ill patients as a possible improve- ment of conventional microbiology culture diagnostic still is technically difficult (8). In particular, the contamination of PCR reagents with bacterial DNA, e.g., contamination of the bacterium-derived polymerases, is a major problem that pre- vents the high sensitivity provided by PCR technology (6, 20, 25, 29; E. C. Bottger, Letter, Clin. Chem. 36:1258-1259, 1990). Nevertheless, it has been shown that it is possible to detect bacterial DNA from clinical samples like blood (17), plasma (8), cerebrospinal fluid (21, 26), and other specimens (22, 26). In contrast to these new diagnostic approaches, blood cultures are time consuming and often yield false-negative results due to unacceptably low sensitivity, even though the patient has significant signs of systemic bacterial infection.

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TO STUDY THE ANTIMICROBIAL PROPERTIES OF GARLIC AGAINST GRAM POSITIVE & GRAM NEGATIVE BACTERIA

TO STUDY THE ANTIMICROBIAL PROPERTIES OF GARLIC AGAINST GRAM POSITIVE & GRAM NEGATIVE BACTERIA

Preparation of Bacterial Culture:-This experiment involved three different types of micro organisms which are from gram negative (Escherichia coli), gram positive bacteria (Staphylococcus aureus) and (Enterococcus faecalis). The starter culture was obtained from Microbiology Laboratory of Government Medical College Srinagar. The streaking process was done in a laminar flow cabinet under sterile conditions to prevent contamination and each Petri plate was sealed with Para film. Then the plates were incubated in BOD incubator (Model No. NSW-152) at 37 0 C for 24 hours. The single colony as shown in figure. 3.4 were obtained by using streak plating method. One colony of bacteria was isolated and was suspended in 10 ml of saline water and shaken well on vortex (Model SPINIK-1719). It was then allowed to stand at room temperature for ten minutes.

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