Oral immunotherapy for Helicobacter pylori: Can it be trusted? A systematic review.

BACKGROUND: Helicobacter pylori (H. pylori) is a rod-shaped, gram-negative, microaerophilic bacterium that can be identified by gram staining. Its relationship with cancer is significant since it is involved in approximately 80% of gastric cancers and 5.5% of all malignant cancers. Two lines of treatment have been defined for H. pylori, but almost 40% of patients do not respond to the first line. Recent trials have investigated oral Immunotherapy as a new treatment method. The aim of this systematic review was to investigate the potential effects of oral Immunotherapy on eradication rate of H. pylori in human studies. METHODS: The systematic review was performed according to PRISMA guidelines. We searched online databases, including Scopus, PubMed, and Web of Science (ISI). Our search strategy was limited to English articles and studies on human populations that use oral immunotherapy for H. pylori. RESULTS: The total number of primary research records in different databases was 2775. After removing duplicate articles (n = 870), we excluded 1829 for reasons including non-human studies, irrelevance to our study objective, non-English language, or lack of information. Of the remaining 76 articles, only seven had sufficient information, and the rest were excluded. The studies were divided into two groups: those that used bovine antibody and those that used immunoglobulin Y to eradicate H. pylori. CONCLUSION: In the group of Immunoglobulin Y, three out of four studies suggest that using Immunoglobulin Y for the treatment of H. pylori infection is significant. However, the group using bovine antibody for the treatment of H. pylori infection has various results, as two out of three studies concluded that bovine antibody therapy is not significant.

Synthesis of New S-S and C-C Bonds by Photoinitiated Radical Recombination Reactions in the Gas Phase.

Photoinitiated radical chemistry has proven to be useful for breaking covalent bonds within many biomolecules in the gas phase. Herein, we demonstrate that radical chemistry is useful for bond synthesis in the gas phase. Single peptides containing two cysteine residues capped with propylmercaptan (PM) often form disulfide bonds following ultraviolet excitation at 266 nm and loss of both PM groups. Similarly, noncovalently bound peptide pairs where each peptide contains a single cysteine residue can be induced to form disulfide bonds. Comparison with disulfide bound species sampled directly from solution yields identical collisional activation spectra, suggesting that native disulfide bonds have been recapitulated in the gas phase syntheses. Another approach utilizing radical chemistry for covalent bond synthesis involves creation of a reactive diradical that can first abstract hydrogen from a target peptide, creating a new radical site, and then recombine the second radical with the new radical to form a covalent bond. This chemistry is illustrated with 2-(hydroxymethyl-3,5-diiodobenzoate)-18-crown-6 ether, which attaches noncovalently to protonated primary amines in peptides and proteins. Following photoactivation and crosslinking, the site of noncovalent adduct attachment can frequently be determined. The ramifications of these observations on peptide structure and noncovalent attachment of 18-crown-6-based molecules is discussed.

The innate capacity of proteins to protect against reactive radical species.

Maintaining redox homeostasis, or the balance of oxidant and antioxidant forces, is essential for proper cellular functioning in biology. Although the antioxidant nature of many small molecules such as vitamin c and glutathione have been thoroughly investigated, contributions to redox homeostasis from larger biomolecules have received less attention. Evidence has shown that some proteins are antioxidant (in a non-catalytic sense), but large scale examination of this property for a diverse set of proteins has proven difficult. Herein, radical-directed dissociation mass spectrometry (RDD-MS) is used to examine the antioxidant capacity of a series of proteins with diverse biological roles, persistence intervals, and localizations. Digestion of these proteins reveals that all contain antioxidant peptide regions. Examination of the amino acid content of the antioxidant peptides does not reveal significant differences relative to normal peptides, suggesting that sequence may be more important than residue content. Sequence homology analysis across organisms reveals that antioxidant regions are frequently conserved, although many of these regions are also known to have other functions which may have influenced evolutionary pressure. Regardless of the origin, it is clear that many proteins may play secondary roles as sacrificial antioxidants within the cellular milieu.

Learning curve in robotic colorectal surgery.

With the rapid adoption of robotics in colorectal surgery, there has been growing interest in the pace at which surgeons gain competency, as it may aid in self-assessment or credentialing. Therefore, we sought to evaluate the learning curve of an expert laparoscopic colorectal surgeon who performed a variety of colorectal procedures robotically. This is a retrospective review of a prospective database of 111 subsequent colorectal procedures performed by a single colorectal surgeon. The cumulative summation technique (CUSUM) was used to construct a learning curve for robotic proficiency by analyzing total operative and console times. Postoperative outcomes including length of stay, 30-day complications, and 30-day readmission rates were evaluated. Chi-square and one-way ANOVA (including Kruskal-Wallis) tests were used to evaluate categorical and continuous variables. Our patient cohort had a mean age of 62.4, mean BMI of 26.9, and mean ASA score of 2.41. There were two conversions to open surgery. The CUSUM graph for console time indicated an initial decrease at case 13 and another decrease at case 83, generating 3 distinct performance phases: learning (n = 13), competence (n = 70), and mastery (n = 28). An interphase comparison revealed no significant differences in age, gender, BMI, ASA score, types of procedures, or indications for surgery between the three phases. Over the course of the study, both mean surgeon console time and median length of stay decreased significantly (p = 0.00017 and p = 0.016, respectively). Although statistically insignificant, there was a downward trend in total operative time and postoperative complication rates. Learning curves for robotic colorectal surgery are commonly divided into three performance phases. Our findings contribute to the construction of a reliable learning curve for the transition of colorectal surgeons to robotics. Furthermore, they may help guide the stepwise training and credentialing of new robotic surgeons.