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Immunology is an important component of the medical curriculum. It provides a foundation for understanding the cellular and molecular processes by which the body protects itself from external substances and the immunological responses that contribute to the development of many illnesses. The inclusion of immunology in an osteopathic medical curriculum is essential to understanding the body’s defense systems as well as the alignment of osteopathic concepts with immunology. By encompassing innate and adaptive immunity, immunology reflects the interconnectedness of the body’s systems and the foundation for self-regulation inherent in osteopathy. A problem facing medical educators is determining how to facilitate students’ learning of immunological concepts in a way that will help them retain and apply the material throughout their clinical years and beyond. This paper aims to provide an immunology education framework designed to effectively integrate immunology topics across the preclinical courses of an osteopathic medical curriculum. Drawing insights from an extensive review of the literature and current medical curricula, we propose an integrative curriculum model that broadly incorporates fundamental concepts of immunology across multiple disciplines and systems-based courses horizontally as well as vertically over the preclinical years using clinical presentations and laboratory findings and further connecting them to osteopathic principles. This integrative curriculum will augment medical students’ understanding of immunology, making them better able to connect core concepts with clinical applications and enhance their application of immunological concepts in osteopathic patient care in alignment with the NBOME guidelines. Using the proposed integrative medical curriculum may better prepare medical students for providing holistic medical care and guidance to their future patients.

Abstract Background The main objective of this study is to compare the effectiveness of toothpaste formulations in giving total protection to the oral cavity. So, three important solution properties: surface tension, conductivity, and pH measurements, have been investigated for eight kinds of commercial herbal and non-herbal based toothpaste of Nepal. The study was extended to evaluate the antibacterial efficacy of toothpaste formulations against the Gram-positive bacteria Staphylococcus aureus (S. aureus) and Gram-negative bacteria Escherichia coli (E. coli), and this was done by standard agar well diffusion technique. Amikacin (30 μg/disk) was used as a positive control to compare the antibacterial potency of the investigated toothpaste. Results The surface tension of all toothpaste formulations increased with the decrease in concentration. However, the conductivity of the formulations decreased with the decrease in concentration. The highest pH of 8.24 was recorded for Dabur Super Salt (DSS) and all values were found to be higher in tap water solutions. All toothpaste formulations showed significant growth inhibition against both S. aureus and E. coli. The overall antibacterial sensitivity of Dabur Red (DR) is higher for S. aureus. The solid material content was found to be highest for Dabur Herbal Gel (DHG) and lowest for Pepsodent (PD). Conclusion The findings of the present study showed all toothpaste formulations as effective in inhibiting the growth of tested bacterial species. Toothpaste formulations were found slightly alkaline, which favors bacterial growth inhibition. Increasing surface tension and decreasing conductivity value of toothpaste relative to a decrease in concentration favor its desirable cleansing action.

Comparative genomic sequencing of laboratory-derived vancomycin-intermediate Staphylococcusaureus (VISA) (MM66-3 and MM66-4) revealed unique mutations in both MM66-3 (in apt and ssaA6), and MM66-4 (in apt and walK), compared to hetero-VISA parent strain MM66. Transcriptional profiling revealed that both MM66 VISA shared 79 upregulated genes and eight downregulated genes. Of these, 30.4% of the upregulated genes were associated with the cell envelope, whereas 75% of the downregulated genes were associated with virulence. In concordance with mutations and transcriptome alterations, both VISA strains demonstrated reduced autolysis, reduced growth in the presence of salt and reduced virulence factor activity. In addition to mutations in genes linked to cell wall metabolism (ssaA6 and walK), the same mutation in apt which encodes adenine phosphoribosyltransferase, was confirmed in both MM66 VISA. Apt plays a role in both adenine metabolism and accumulation and both MM66 VISA grew better than MM66 in the presence of adenine or 2-fluoroadenine indicating a reduction in the accumulation of these growth inhibiting compounds in the VISA strains. MM66 apt mutants isolated via 2-fluoroadenine selection also demonstrated reduced susceptibility to the cell wall lytic dye Congo red and vancomycin. Finding that apt mutations contribute to reduced vancomycin susceptibility once again suggests a role for altered purine metabolism in a VISA mechanism.

Glucarate, an oxidized product of glucose, is a major serum organic acid in humans. Still, its role as a carbon source for a pathogen colonizing hosts has not been studied. We detected high-level expression of a potential glucarate permease encoding gene gudT when Salmonella enterica serovar Typhimurium are exposed to hydrogen gas (H2), a gaseous by-product of gut commensal metabolism. A gudT strain of Salmonella is deficient in glucarate-dependent growth, however, it can still use other monosaccharides, such as glucose or galactose. Complementation of the gudT mutant with a plasmid harbouring gudT restored glucarate-dependent growth to wild-type (WT) levels. The gudT mutant exhibits attenuated virulence: the mean time of death for mice inoculated with WT strain was 2 days earlier than for mice inoculated with the gudT strain. At 4 days postinoculation, liver and spleen homogenates from mice inoculated with a gudT strain contained significantly fewer viable Salmonella than homogenates from animals inoculated with the parent. The parent strain grew well H2-dependently in a minimal medium with amino acids and glucarate provided as the sole carbon sources, whereas the gudT strain achieved approximately 30% of the parent strain's yield. Glucarate-mediated growth of a mutant strain unable to produce H2 was stimulated by H2 addition, presumably owing to the positive transcriptional response to H2. Gut microbiota-produced molecular hydrogen apparently signals Salmonella to catabolize an alternative carbon source available in the host. Our results link a gut microbiome-produced diffusible metabolite to augmenting bacterial pathogenesis.

ABSTRACT Salmonella enterica serovar Typhimurium contains three distinct respiratory hydrogenases, all of which contribute to virulence. Addition of H2 significantly enhanced the growth rate and yield of S. Typhimurium in an amino acid-containing medium; this occurred with three different terminal respiratory electron acceptors. Based on studies with site-specific double-hydrogenase mutant strains, most of this H2-dependent growth increase was attributed to the Hyb hydrogenase, rather than to the Hya or Hyd respiratory H2-oxidizing enzymes. The wild type strain with H2 had 4.0-fold greater uptake of 14C-labeled amino acids over a period of minutes than did cells incubated without H2. The double-uptake hydrogenase mutant containing only the Hyb hydrogenase transported amino acids H2 dependently like the wild type. The Hyb-only-containing strain produced a membrane potential comparable to that of the wild type. The H2-stimulated amino acid uptake of the wild type and the Hyb-only strain was inhibited by the protonophore carbonyl cyanide m-chlorophenylhydrazone but was less affected by the ATP synthase inhibitor sodium orthovanadate. In the wild type, proteins TonB and ExbD, which are known to couple proton motive force (PMF) to transport processes, were induced by H2 exposure, as were the genes corresponding to these periplasmic PMF-coupling factors. However, studies on tonB and exbD single mutant strains could not confirm a major role for these proteins in amino acid transport. The results link H2 oxidation via the Hyb enzyme to growth, amino acid transport, and expression of periplasmic proteins that facilitate PMF-mediated transport across the outer membrane. IMPORTANCE Complex carbohydrates consumed by animals are fermented by intestinal microflora, and this leads to molecular hydrogen production. Salmonella enterica serovar Typhimurium can utilize this gas via three distinct respiratory hydrogenases, all of which contribute to virulence. Since H2 oxidation can be used to conserve energy, we predicted that its use may augment bacterial growth in nutrient-poor media or in competitive environments within H2-containing host tissues. We thus investigated the effect of added H2 on the growth of Salmonella Typhimurium in carbon-poor media with various terminal respiratory electron acceptors. The positive effects of H2 on growth led to the realization that Salmonella has mechanisms to increase carbon acquisition when oxidizing H2. We found that H2 oxidation via one of the respiration-linked enzymes, the Hyb hydrogenase, led to increased growth, amino acid transport, and expression of periplasmic proteins that facilitate proton motive force-mediated transport across the outer membrane.

Background: This is the first study to determine whether nonskid slipper socks in contact with the hospital floor and worn into bed contaminate bed linen., Purpose: The main purpose of the study was to determine whether contamination of hospital linen occurred with bacteria transferred from the soles of nonskid slipper socks that have touched the floor., Methods: This study mimicked real patients walking on a hospital floor wearing slipper socks and getting back into bed with the slipper socks on. Swab samples were collected from the surfaces of the hospital floor, nonskid slipper sock bottoms, and bed linen in 2 Midwestern hospitals. From the samples, bacterial isolates were identified and tested for antibiotic resistance., Results: Isolates obtained from the samples were identified on all 3 surfaces at both hospitals, indicating spread of the bacteria from floor to the bed linen via the nonskid slipper socks. Antibiotic sensitivity test revealed that a significant number of isolates collected were resistant to at least 2 antibiotics tested., Conclusion: This study demonstrates cross-contamination of bed linen with potentially pathogenic bacteria present on the hospital floor via contact with patient-worn nonskid slipper socks. A simple practice change regarding the wearing of slipper socks could play an important role in preventing pathogen transfer to the bed linen. Awareness of the likelihood of hand contamination after touching the sock bottoms that have come in contact with the hospital floor should also be considered.