Is surgical resection justified for pancreatic ductal adenocarcinoma with distant abdominal organ metastasis? A position paper by experts in pancreatic surgery at the Joint Meeting of the International Association of Pancreatology (IAP) & the Japan Pancreas Society (JPS) 2022 in Kyoto.

Pancreatic ductal adenocarcinoma (PDAC) is a typical refractory malignancy, and many patients have distant organ metastases at diagnosis, such as liver metastasis and peritoneal dissemination. The standard treatment for unresectable PDAC with distant organ metastasis (UR-M) is chemotherapy, but the prognosis remained poor. However, with recent dramatic developments in chemotherapy, the prognosis has gradually improved, and some patients have experienced marked shrinkage or disappearance of their metastatic lesions. With this trend, attempts have been made to resect a small number of metastases (so-called oligometastases) in combination with the primary tumor or to resect the primary and metastatic tumor in patients with a favorable response to anti-cancer treatment after a certain period of time (so-called conversion surgery). An international consensus meeting on surgical treatment for UR-M PDAC was held during the Joint Congress of the 26th Meeting of the International Association of Pancreatology (IAP) and the 53rd Annual Meeting of the Japan Pancreas Society (JPS) in Kyoto in July 2022. The presenters showed their indications for and results of surgical treatment for UR-M PDAC and discussed their advantages and disadvantages with the experts. Although these reports were limited to a small number of patients, findings suggest that these surgical treatments for patients with UR-M PDAC who have had a significant response to chemotherapy may contribute to a prognosis of prolonged survival. We hope that this article summarizing the discussion and agreements at the meeting will serve as the basis for future trials and guidelines.

Discovery of new enzymes and metabolic pathways by using structure and genome context.

Assigning valid functions to proteins identified in genome projects is challenging: overprediction and database annotation errors are the principal concerns. We and others are developing computation-guided strategies for functional discovery with 'metabolite docking' to experimentally derived or homology-based three-dimensional structures. Bacterial metabolic pathways often are encoded by 'genome neighbourhoods' (gene clusters and/or operons), which can provide important clues for functional assignment. We recently demonstrated the synergy of docking and pathway context by 'predicting' the intermediates in the glycolytic pathway in Escherichia coli. Metabolite docking to multiple binding proteins and enzymes in the same pathway increases the reliability of in silico predictions of substrate specificities because the pathway intermediates are structurally similar. Here we report that structure-guided approaches for predicting the substrate specificities of several enzymes encoded by a bacterial gene cluster allowed the correct prediction of the in vitro activity of a structurally characterized enzyme of unknown function (PDB 2PMQ), 2-epimerization of trans-4-hydroxy-L-proline betaine (tHyp-B) and cis-4-hydroxy-D-proline betaine (cHyp-B), and also the correct identification of the catabolic pathway in which Hyp-B 2-epimerase participates. The substrate-liganded pose predicted by virtual library screening (docking) was confirmed experimentally. The enzymatic activities in the predicted pathway were confirmed by in vitro assays and genetic analyses; the intermediates were identified by metabolomics; and repression of the genes encoding the pathway by high salt concentrations was established by transcriptomics, confirming the osmolyte role of tHyp-B. This study establishes the utility of structure-guided functional predictions to enable the discovery of new metabolic pathways.

Loss of quaternary structure is associated with rapid sequence divergence in the OSBS family.

The rate of protein evolution is determined by a combination of selective pressure on protein function and biophysical constraints on protein folding and structure. Determining the relative contributions of these properties is an unsolved problem in molecular evolution with broad implications for protein engineering and function prediction. As a case study, we examined the structural divergence of the rapidly evolving o-succinylbenzoate synthase (OSBS) family, which catalyzes a step in menaquinone synthesis in diverse microorganisms and plants. On average, the OSBS family is much more divergent than other protein families from the same set of species, with the most divergent family members sharing <15% sequence identity. Comparing 11 representative structures revealed that loss of quaternary structure and large deletions or insertions are associated with the family's rapid evolution. Neither of these properties has been investigated in previous studies to identify factors that affect the rate of protein evolution. Intriguingly, one subfamily retained a multimeric quaternary structure and has small insertions and deletions compared with related enzymes that catalyze diverse reactions. Many proteins in this subfamily catalyze both OSBS and N-succinylamino acid racemization (NSAR). Retention of ancestral structural characteristics in the NSAR/OSBS subfamily suggests that the rate of protein evolution is not proportional to the capacity to evolve new protein functions. Instead, structural features that are conserved among proteins with diverse functions might contribute to the evolution of new functions.

Homology models guide discovery of diverse enzyme specificities among dipeptide epimerases in the enolase superfamily.

The rapid advance in genome sequencing presents substantial challenges for protein functional assignment, with half or more of new protein sequences inferred from these genomes having uncertain assignments. The assignment of enzyme function in functionally diverse superfamilies represents a particular challenge, which we address through a combination of computational predictions, enzymology, and structural biology. Here we describe the results of a focused investigation of a group of enzymes in the enolase superfamily that are involved in epimerizing dipeptides. The first members of this group to be functionally characterized were Ala-Glu epimerases in Eschericiha coli and Bacillus subtilis, based on the operon context and enzymological studies; these enzymes are presumed to be involved in peptidoglycan recycling. We have subsequently studied more than 65 related enzymes by computational methods, including homology modeling and metabolite docking, which suggested that many would have divergent specificities;, i.e., they are likely to have different (unknown) biological roles. In addition to the Ala-Phe epimerase specificity reported previously, we describe the prediction and experimental verification of: (i) a new group of presumed Ala-Glu epimerases; (ii) several enzymes with specificity for hydrophobic dipeptides, including one from Cytophaga hutchinsonii that epimerizes D-Ala-D-Ala; and (iii) a small group of enzymes that epimerize cationic dipeptides. Crystal structures for certain of these enzymes further elucidate the structural basis of the specificities. The results highlight the potential of computational methods to guide experimental characterization of enzymes in an automated, large-scale fashion.

Health literacy and parenting infants at home: protocol for a qualitative systematic review of parents' experiences.

OBJECTIVE: This systematic review will identify and synthesize the available qualitative evidence regarding parents' experiences of health literacy in parenting infants at home. INTRODUCTION: Parental health literacy, which is essential for parents' and children's health, is associated with parents' health knowledge, parenting practices, and children's health outcomes. Parents face difficulties pertaining to their health literacy skills in daily health education and health care for their infants; therefore, understanding their parenting experience with infants from a health literacy perspective is important for health professionals. This review will evaluate and integrate qualitative evidence regarding parental experiences of health literacy in daily parenting of infants at home. INCLUSION CRITERIA: This review will include qualitative data from empirical studies describing parents' experiences of health literacy in parenting infants at home. Parents of infants (0-1 year of age) living at home in Organisation for Economic Co-operation and Development member countries will be included. METHODS: This review will follow the JBI approach for qualitative systematic reviews. The following databases will be searched for published and unpublished studies: MEDLINE (EBSCOhost), CINAHL (EBSCOhost), PsycINFO (EBSCOhost), and ProQuest Health and Medical Collection (in English and Japanese); Open Access Theses and Dissertations (in English); and Ichushi-Web, CiNii, and the Institutional Repositories Database (in Japanese). Study selection, data extraction, and critical appraisal of the methodological quality of studies will be undertaken by 2 reviewers independently. Data synthesis will be conducted using the meta-aggregation approach, and the synthesized findings will be assessed using the ConQual approach. REVIEW REGISTRATION: PROSPERO CRD42022345187.

Thoracoscopic enucleation of an esophageal glomus tumor in the prone position: a case report and literature review.

BACKGROUND: Glomus tumors (GT) generally occur in the skin. However, esophageal GT, an extremely rare condition, has no established standardized treatment guidelines. Herein, we report the case of an esophageal GT successfully removed by thoracoscopic enucleation in the prone position using intra-esophageal balloon compression. CASE PRESENTATION: A 45-year-old man underwent an annual endoscopic examination and was found to have a submucosal tumor in the lower esophagus. Endoscopic ultrasound (EUS) revealed a hyperechoic mass originating from the muscular layer. Contrast-enhanced computed tomography identified a 2 cm mass lesion with high contrast enhancement in the right side of the lower esophagus. Pathologic findings of EUS-guided fine needle aspiration biopsy (EUS-FNA) revealed round to spindle shaped atypical cells without mitotic activity. Immunohistochemically, the tumor was positive for alpha-smooth muscle actin, but negative for CD34, desmin, keratin 18, S-100 protein, melan A, c-kit, and STAT6. He was diagnosed with an esophageal GT and a thoracoscopic approach to tumor resection was planned. Under general anesthesia, a Sengstaken-Blakemore (SB) tube was inserted into the esophagus. The patient was placed in the prone position and a right thoracoscopic approach was achieved. The esophagus around the tumor was mobilized and the SB tube balloon inflated to compress the tumor toward the thoracic cavity. The muscle layer was divided and the tumor was successfully enucleated without mucosal penetration. Oral intake was initiated on postoperative day (POD) 3 and the patient discharged on POD 9. No surgical complications or tumor metastasis were observed during the 1-year postoperative follow-up. CONCLUSIONS: As malignancy criteria for esophageal GT are not yet established, the least invasive procedure for complete resection should be selected on a case-by-case basis. Thoracoscopic enucleation in the prone position using intra-esophageal balloon compression is useful to treat esophageal GT on the right side of the esophagus.

Update of risk factors for surgical site infection in clean-contaminated wounds after gastroenterological surgery: An analysis of 1,878 participants enrolled in 2 recent randomized control trials for the prevention of surgical site infection.

BACKGROUND: Clean-contaminated wounds should be the main target for reducing the burden of harm caused by surgical site infection after gastroenterological surgery. METHODS: The present study targeted 1,973 patients enrolled in 2 randomized controlled trials to evaluate the efficacy of intraoperative interventions for incisional surgical site infection prevention after gastroenterological surgery with clean-contaminated wounds. Patients were reassessed, and preoperative and postoperative variables were collected. Risk factors for surgical site infection were identified by univariate and multivariate analyses. RESULTS: The study population included 1,878 patients, among whom 213 (11.3%) developed overall surgical site infection and 119 (6.3%) developed incisional surgical site infection. A multivariate analysis revealed that steroid or immunosuppressant use (odds ratio 3.03; 95% confidence interval 1.37-6.73, P = .0064), open surgery (odds ratio 1.77; 95% confidence interval 1.11-2.83, P = .0167), and long operative time (odds ratio 2.31; 95% confidence interval 1.5-3.56, P < .001) were independent risk factors for incisional surgical site infection. Steroid or immunosuppressant use (odds ratio 2.62; 95% confidence interval 1.29-5.33, P = .0078), open surgery (odds ratio 2.13; 95% confidence interval 1.44-3.16, P < .001), and long operative time (odds ratio 2.92; 95% confidence interval 2.08-4.10, P < .001) were also independent risk factors for overall surgical site infection in the multivariate analysis. Furthermore, a multivariate analysis revealed that a long operative time (odds ratio 3.21; 95% confidence interval 1.69-6.1, P = .00378) was an independent risk factor for incisional surgical site infection in patients who underwent laparoscopic surgery. CONCLUSION: Even under current measures for surgical site infection prevention, surgeons should continue to make efforts to appropriately expand the indication of laparoscopic surgery and to reduce operative times even when performing laparoscopic surgery.

Developing an Instructional Design-Based Dementia Education Program.

Community building is necessary to help create a dementia-inclusive society. In this study, a one-of-a kind dementia education program based on mutual learning using instructional design was developed alongside community members and stakeholders. The purpose was to implement and evaluate this program and gain insight into dementia education for the community. A total of 118 individuals participated in the program; however, data of 80 participants (Male = 26, Female = 54), who completed a questionnaire before and after the program, were analyzed. The results showed a significant pre-post difference in mean total scores on the Attitudes Toward Dementia Scale (32.1 points pre-program vs. 33.7 points post-program). Nine necessary learning topics were identified. The program could successfully teach participants to take the perspectives of various other people, view dementia as something relevant to themselves, and think about specific ways of responding to people with dementia considering their feelings. This study recommends creating education programs using scenario stories that depict the desire of people with dementia to be a part of the community, using visual depictions to create a shared impression and facilitate mutual learning.

A 47-Year-Old Man with Advanced Distal Pancreatic Carcinoma and an Initial Partial Response to Chemotherapy Requiring Celiac Axis Reconstruction of the Common Hepatic Artery and Left Gastric Artery.

BACKGROUND Distal pancreatectomy with en bloc celiac artery resection (DP-CAR) is a curative surgical method for locally advanced pancreatic body cancer; however, arterial reconstruction remains controversial in this procedure. This report presents the case of a 47-year-old man with advanced distal pancreatic carcinoma and initial partial response to chemotherapy who required celiac axis reconstruction of the common hepatic artery and left gastric artery. CASE REPORT A 47-year-old man had loss of appetite. He had a 40-mm hypovascular tumor extending from the pancreatic body to the tail, invading around the celiac artery, common hepatic artery, left gastric artery, and splenic artery. We initiated chemotherapy concurrent with chemo-radiotherapy with S-1 administration. After chemo-radiotherapy, computed tomography (CT) showed tumor shrinkage, indicating partial response, but soft tissue CT density surrounding the celiac axis arteries persisted. We conducted conversion surgery. When the common hepatic artery was clamped during surgery, the intrahepatic arterial blood flow reduced; thus, we reconstructed the middle hepatic artery to the common hepatic artery. The left gastric artery was also reconstructed using the second jejunal artery to prevent ischemic gastropathy. Histopathologic examination showed no tumor cells in the specimen; thus, R0 resection was achieved. CONCLUSIONS Arterial reconstruction can be an option for R0 resection in DP-CAR when hepatic arterial blood flow is reduced due to an intraoperative common hepatic artery clamping test.

Distal partial gastrectomy for gastric tube cancer with intraoperative blood flow evaluation using indocyanine green fluorescence.

With recent advances in the treatment of esophageal cancer and long-term survival after esophagectomy, the number of gastric tube cancer (GTC) has been increasing. Total gastric tube resection with lymph node dissection is considered to be a radical treatment, but it causes high post-operative morbidity and mortality. We report an elderly patient with co-morbidities who developed pyloric obstruction due to GTC after esophagectomy with retrosternal reconstruction. The patient was treated using distal partial gastric tube resection (PGTR) and Roux-en-Y reconstruction with preservation of the right gastroepiploic artery and right gastric artery. Intraoperative blood flow visualization using indocyanine green (ICG) fluorescence demonstrated an irregular demarcation line at the distal side of the preserved gastric tube, indicating a safe surgical margin to completely remove the ischemic area. PGTR with intraoperative ICG evaluation of blood supply in the preserved gastric tube is a safe and less-invasive surgical option in patients with poor physiological condition.

Complete Genome Sequence of Halomonas meridiana Strain Eplume2, Isolated from a Hydrothermal Plume in the Northeast Pacific Ocean.

Halomonas meridiana strain Eplume2 (ATCC BAA-804) is a Gram-negative bacterium isolated from hydrothermal plume seawater in the Northeast Pacific Ocean at a depth of 2,000 m. Here, we report the complete genome sequence of this strain, which has a total size of 4.12 Mbp and a 56.6% G+C content.

Evolution of enzymatic activities in the enolase superfamily: stereochemically distinct mechanisms in two families of cis,cis-muconate lactonizing enzymes.

The mechanistically diverse enolase superfamily is a paradigm for elucidating Nature's strategies for divergent evolution of enzyme function. Each of the different reactions catalyzed by members of the superfamily is initiated by abstraction of the alpha-proton of a carboxylate substrate that is coordinated to an essential Mg(2+). The muconate lactonizing enzyme (MLE) from Pseudomonas putida, a member of a family that catalyzes the syn-cycloisomerization of cis,cis-muconate to (4S)-muconolactone in the beta-ketoadipate pathway, has provided critical insights into the structural bases for evolution of function within the superfamily. A second, divergent family of homologous MLEs that catalyzes anti-cycloisomerization has been identified. Structures of members of both families liganded with the common (4S)-muconolactone product (syn, Pseudomonas fluorescens, gi 70731221 ; anti, Mycobacterium smegmatis, gi 118470554 ) document that the conserved Lys at the end of the second beta-strand in the (beta/alpha)(7)beta-barrel domain serves as the acid catalyst in both reactions. The different stereochemical courses (syn and anti) result from different structural strategies for determining substrate specificity: although the distal carboxylate group of the cis,cis-muconate substrate attacks the same face of the proximal double bond, opposite faces of the resulting enolate anion intermediate are presented to the conserved Lys acid catalyst. The discovery of two families of homologous, but stereochemically distinct, MLEs likely provides an example of "pseudoconvergent" evolution of the same function from different homologous progenitors within the enolase superfamily, in which different spatial arrangements of active site functional groups and substrate specificity determinants support catalysis of the same reaction.

Evolution of structure and function in the o-succinylbenzoate synthase/N-acylamino acid racemase family of the enolase superfamily.

Understanding how proteins evolve to provide both exquisite specificity and proficient activity is a fundamental problem in biology that has implications for protein function prediction and protein engineering. To study this problem, we analyzed the evolution of structure and function in the o-succinylbenzoate synthase/N-acylamino acid racemase (OSBS/NAAAR) family, part of the mechanistically diverse enolase superfamily. Although all characterized members of the family catalyze the OSBS reaction, this family is extraordinarily divergent, with some members sharing <15% identity. In addition, a member of this family, Amycolatopsis OSBS/NAAAR, is promiscuous, catalyzing both dehydration and racemization. Although the OSBS/NAAAR family appears to have a single evolutionary origin, no sequence or structural motifs unique to this family could be identified; all residues conserved in the family are also found in enolase superfamily members that have different functions. Based on their species distribution, several uncharacterized proteins similar to Amycolatopsis OSBS/NAAAR appear to have been transmitted by lateral gene transfer. Like Amycolatopsis OSBS/NAAAR, these might have additional or alternative functions to OSBS because many are from organisms lacking the pathway in which OSBS is an intermediate. In addition to functional differences, the OSBS/NAAAR family exhibits surprising structural variations, including large differences in orientation between the two domains. These results offer several insights into protein evolution. First, orthologous proteins can exhibit significant structural variation, and specificity can be maintained with little conservation of ligand-contacting residues. Second, the discovery of a set of proteins similar to Amycolatopsis OSBS/NAAAR supports the hypothesis that new protein functions evolve through promiscuous intermediates. Finally, a combination of evolutionary, structural, and sequence analyses identified characteristics that might prime proteins, such as Amycolatopsis OSBS/NAAAR, for the evolution of new activities.

Prediction and biochemical demonstration of a catabolic pathway for the osmoprotectant proline betaine.

UNLABELLED: Through the use of genetic, enzymatic, metabolomic, and structural analyses, we have discovered the catabolic pathway for proline betaine, an osmoprotectant, in Paracoccus denitrificans and Rhodobacter sphaeroides. Genetic and enzymatic analyses showed that several of the key enzymes of the hydroxyproline betaine degradation pathway also function in proline betaine degradation. Metabolomic analyses detected each of the metabolic intermediates of the pathway. The proline betaine catabolic pathway was repressed by osmotic stress and cold stress, and a regulatory transcription factor was identified. We also report crystal structure complexes of the P. denitrificans HpbD hydroxyproline betaine epimerase/proline betaine racemase with l-proline betaine and cis-hydroxyproline betaine. IMPORTANCE: At least half of the extant protein annotations are incorrect, and the errors propagate as the number of genome sequences increases exponentially. A large-scale, multidisciplinary sequence- and structure-based strategy for functional assignment of bacterial enzymes of unknown function has demonstrated the pathway for catabolism of the osmoprotectant proline betaine.

Prediction and characterization of enzymatic activities guided by sequence similarity and genome neighborhood networks.

Metabolic pathways in eubacteria and archaea often are encoded by operons and/or gene clusters (genome neighborhoods) that provide important clues for assignment of both enzyme functions and metabolic pathways. We describe a bioinformatic approach (genome neighborhood network; GNN) that enables large scale prediction of the in vitro enzymatic activities and in vivo physiological functions (metabolic pathways) of uncharacterized enzymes in protein families. We demonstrate the utility of the GNN approach by predicting in vitro activities and in vivo functions in the proline racemase superfamily (PRS; InterPro IPR008794). The predictions were verified by measuring in vitro activities for 51 proteins in 12 families in the PRS that represent ∼85% of the sequences; in vitro activities of pathway enzymes, carbon/nitrogen source phenotypes, and/or transcriptomic studies confirmed the predicted pathways. The synergistic use of sequence similarity networks3 and GNNs will facilitate the discovery of the components of novel, uncharacterized metabolic pathways in sequenced genomes.

Evolution of enzymatic activities in the enolase superfamily: N-succinylamino acid racemase and a new pathway for the irreversible conversion of D- to L-amino acids.

Members of the mechanistically diverse enolase superfamily catalyze reactions that are initiated by abstraction of the alpha-proton of a carboxylate anion to generate an enolate anion intermediate that is stabilized by coordination to a Mg2+ ion. The catalytic groups, ligands for an essential Mg2+ and acid/base catalysts, are located in the (beta/alpha)8-barrel domain of the bidomain proteins. The assigned physiological functions in the muconate lactonizing enzyme (MLE) subgroup (Lys acid/base catalysts at the ends of the second and sixth beta-strands in the barrel domain) are cycloisomerization (MLE), dehydration (o-succinylbenzoate synthase; OSBS), and epimerization (L-Ala-D/L-Glu epimerase). We previously studied a putatively promiscuous member of the MLE subgroup with uncertain physiological function from Amycolatopsis that was discovered based on its ability to catalyze the racemization of N-acylamino acids (N-acylamino acid racemase; NAAAR) but also catalyzes the OSBS reaction [OSBS/NAAAR; Palmer, D. R., Garrett, J. B., Sharma, V., Meganathan, R., Babbitt, P. C., and Gerlt, J. A. (1999) Biochemistry 38, 4252-4258]. In this manuscript, we report functional characterization of a homologue of this protein encoded by the genome of Geobacillus kaustophilus as well as two other proteins that are encoded by the same operon, a divergent member of the Gcn5-related N-acetyltransferase (GNAT) superfamily of enzymes whose members catalyze the transfer an acyl group from an acyl-CoA donor to an amine acceptor, and a member of the M20 peptidase/carboxypeptidase G2 family. We determined that the member of the GNAT superfamily is succinyl-CoA:D-amino acid N-succinyltransferase, the member of the enolase superfamily is N-succinylamino acid racemase (NSAR), and the member of the M20 peptidase/carboxypeptidase G2 family is N-succinyl-L-amino acid hydrolase. We conclude that (1) these enzymes constitute a novel, irreversible pathway for the conversion of D- to L-amino acids and (2) the NSAR reaction is a new physiological function in the MLE subgroup. The NSAR is also functionally promiscuous and catalyzes an efficient OSBS reaction; intriguingly, the operon for menaquinone biosynthesis in G. kaustophilus does not encode an OSBS, raising the possibility that the NSAR is a bifunctional enzyme rather than an accidentally promiscuous enzyme.