Renal Failure Without Hemodialysis Is a Risk Factor for Postoperative Complications in Colorectal Cancer Surgery.

Background/Aim: Surgical outcomes of colorectal cancer (CRC) in patients with renal failure (RF) remain to be clarified. The objective of this research was to investigate how RF impacts the surgical outcomes in patients with CRC. Patients and Methods: A retrospective analysis was performed on clinical data from 633 patients who underwent colorectal resection for CRC between January 2017 and December 2021. Outcomes of the patients with and without RF were compared. RF was defined as estimated Glomerular Filtration Rate less than 30. Results: Forty-five (7%) patients with RF were identified. RF was a significant risk factor for postoperative complications after colorectal cancer surgery (odds ratio=2.19, 95% confidence interval=1.08-4.42, p=0.0284). The patients with RF had significantly more comorbidity (p=0.016), and higher American Society of Anesthesiologists physical status (p<0.01). Hemoglobin level (p<0.01) and PNI (p<0.01) were significantly lower in those with RF. Postoperative complications were significantly higher (p=0.016), and the postoperative hospital stay was significantly longer (p<0.01) among patients with RF compared to those without RF. Patients with RF, excluding those undergoing hemodialysis, had significantly more complications compared to those without RF (p=0.004). Conclusion: Careful attention should be paid to perioperative management in RF colorectal cancer patients.

Risk factors and clinical significance of subcutaneous emphysema after robot-assisted laparoscopic rectal surgery: a single-center experience.

Subcutaneous emphysema (SE) is a complication of laparoscopic surgery, potentially resulting in severe respiratory failure. No reports to date have focused on SE during robot-assisted (RA) rectal surgery. We aimed to reveal the risk factors and clinical significance of SE after RA/laparoscopic rectal surgery. We retrospectively reviewed 221 consecutive patients who underwent RA/laparoscopic rectal surgery. The occurrence of SE was evaluated on postoperative radiographs. Laparoscopic surgery was performed in 120 patients and RA in 101. SE developed in 55 (24.9%) patients. Logistic regression analysis identified RA surgery (odds ratio [OR]: 4.89, 95% confidence interval [CI] 2.13-11.22, p < 0.001), higher age (OR: 1.06, 95% CI 1.03-1.11, p < 0.001), lower body mass index (BMI) (OR: 0.79, 95% CI 0.67-0.93, p = 0.004), thinner subcutaneous layer (OR: 0.88, 95% CI 0.79-0.98, p = 0.02), and lateral lymph node dissection (OR: 9.43, 95% CI 2.44-36.42, p < 0.001) as risk factors for SE. Maximum end-tidal CO2 was significantly higher in the SE than the non-SE cohort (p < 0.001). There was no difference in postoperative complication rate or length of hospital stay. Lower BMI (OR: 0.79, 95% CI 0.62-0.97, p = 0.02) and thinner subcutaneous layer (OR: 0.84, 95% CI 0.71-0.97, p = 0.01) were predictive factors in the RA cohort. SE occurs more frequently in RA compared with laparoscopic surgery. SE has a modest impact on short-term outcomes, but may occasionally cause severe problems. The indication of RA surgery should be considered carefully in high-risk elderly patients.

Optimal Surgical Method and Timing for Low-birth-weight Esophageal Atresia Babies: Multi-institutional Observational Study.

AIM OF THE STUDY: Previous research has shown that low birth weight is one of the risk factors for esophageal atresia. However, there remains a paucity of evidence on the timing and the treatment method. METHOD: Data were collected using a multi-institutional observational study in 11 hospitals that performed surgeries on esophageal atresia babies whose birth weights were ≤1500 g from 2001 to 2020. RESULTS: Of the 46 patients analyzed, median birth weight was 1233 (IQR 1042-1412) g. Within 46 cases, 19 (41%) underwent definitive esophageal anastomosis at the median of age in 8 (IQR 2-101) days. Thirteen out of 19 experienced either closure of tracheoesophageal fistula, gastrostomy, or esophageal banding at the first operation, followed by esophageal anastomosis. Seven infants, including four cases of <1000 g, underwent anastomosis after one month of age to wait for weight gain (variously 2-3000 g). Twenty-one out of 27 infants (78%) who did not receive anastomosis died within one year of age, including 21 (78 %) with major cardiac anomalies and 24 (89%) with severe chromosomal anomalies (trisomy 18). Six survivors in this group, all with trisomy 18, lived with palliative surgical treatments. CONCLUSION: In our study, the definitive esophageal anastomosis was effective either at the first operation or as a later treatment after gaining weight. Although having severe anomalies, some infants receive palliative surgical treatments, and the next surgery was considered depending on their condition. EVIDENCE LEVEL: II.

Monitoring the Kinase Activity of Heme-Based Oxygen Sensors and Its Dependence on O2 and Other Ligands Using Phos-Tag Electrophoresis.

The nonradioactive method, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) in the presence of Phos-tag (Phos-tag electrophoresis), is used to evaluate a kinase autophosphorylation and/or phosphotransfer reaction from a kinase/ATP to its protein substrate. This method outperforms radioisotope methods using [32P]ATP for detecting trace amounts of phosphorylated protein in fresh protein preparations. Phos-tag electrophoresis has been used to perform detailed analyses of the kinase activity of a heme-based oxygen sensor-specifically, a globin-coupled histidine kinase from the soil bacterium Anaeromyxobacter sp. Fw109-5 (AfGcHK).

Characterization of the interaction between the tumour suppressor p53 and heme and its role in the protein conformational dynamics studied by various spectroscopic techniques and hydrogen/deuterium exchange coupled with mass spectrometry.

The tumour suppressor p53 regulates the expression of a myriad of proteins that are important for numerous cellular processes, including apoptosis, cell cycle arrest, DNA repair, metabolism, and even autophagy and ferroptosis. Aside from DNA, p53 can interact with many types of partners including proteins and small organic molecules. The ability of p53 to interact with heme has been reported so far. In this study, we used various spectroscopic studies to conduct a thorough biophysical characterization of the interaction between p53 and heme concerning the oxidation, spin, coordination, and ligand state of heme iron. We found that the p53 oligomeric state and zinc biding ability are preserved upon the interaction with heme. Moreover, we described the effect of heme binding on the conformational dynamics of p53 by hydrogen/deuterium exchange coupled with mass spectrometry. Specifically, the conformational flexibility of p53 is significantly increased upon interaction with heme, while its affinity to a specific DNA sequence is reduced by heme. The inhibitory effect of DNA binding by heme is partially reversible. We discuss the potential heme binding sites in p53 with respect to the observed conformational dynamics changes and perturbed DNA-binding ability of p53 upon interaction with heme.

A strategy to prevent tracheo-innominate artery fistula in the course of laryngotracheal separation: 9-year experience in a children's hospital.

AIM OF THE STUDY: Laryngotracheal separation (LTS) is known to be the definitive solution for intractable aspiration pneumonia in neurologically impaired children. Postoperatively, a tracheostomy cannula is usually required. However, there are fatal cannula related complications such as a tracheo-innominate artery fistula (TIAF). We present our methods of preventing TIAF. METHODS: A retrospective review in a single center from 2011 to 2019 identified 57 cases treated with LTS. We divided them into three groups: no pre-existing tracheostomy (n = 26), pre-existing tracheostomy with preservation of the pre-existing fistula (n = 20), and pre-existing tracheostomy without preservation of the pre-existing fistula (n = 11). The first group underwent traditional modified Lindeman's procedure. The second received transection of the trachea above the tracheostomy site, while the third had transection of the trachea at the tracheostomy site and creation of a distal end tracheostomy. Proper length and the angle of the cannula were selected to prevent damaging the innominate artery by the tip of the cannula. If the innominate artery compressed the trachea anteriorly, prophylactic arterial transection was considered. RESULTS: Three patients (5.3%) died from causes unrelated to the surgical treatment. Only one patient had a postoperative TIAF followed by LTS (1.8%). Other postoperative complications were: wound infection (8.8%), intratracheal granuloma (12.3%), intratracheal minor bleeding (10.5%), wound granuloma (43.9%), leakage (1.8%). No one required revision of LTS. CONCLUSION: Success rates of LTS were high without major complications in all three groups and implies a safe operation and a definitive solution to intractable aspiration.

Portosystemic shunt for portal hypertension after Kasai operation in patients with biliary atresia.

PURPOSE: Many biliary atresia (BA) patients will eventually develop liver failure even after a successful Kasai portoenterostomy. A common complication of long-term BA survivors with their native liver is problematic portal hypertension. The aim of this study was to defend the view that portosystemic shunts can delay or negate the need for transplantation in these children. METHODS: A retrospective single center review of the efficacy of portosystemic shunts in BA patients after a successful Kasai portoenterostomy was conducted. RESULTS: From 1991 to 2017, 11 patients received portosystemic shunts. Median age of Kasai operation was 48 (36-61) days. Shunts were performed at the median age of 6.2 (4.1-6.8) years. Three of these eleven patients required subsequent liver transplantation. OS at 5 and 10 years were 90.9% and 81.8%, respectively. TFS at 5 and 10 years were 90.9% and 72.7%, respectively. Long-term complications included mild encephalopathy in 2 patients, hypersplenism in 3, and cholestasis in 1. CONCLUSION: Portosystemic shunt for the treatment of portal hypertension in carefully selected BA patients is an effective option in delaying or negating the need for liver transplantation.

Subtype-specific gout susceptibility loci and enrichment of selection pressure on ABCG2 and ALDH2 identified by subtype genome-wide meta-analyses of clinically defined gout patients.

OBJECTIVES: Genome-wide meta-analyses of clinically defined gout were performed to identify subtype-specific susceptibility loci. Evaluation using selection pressure analysis with these loci was also conducted to investigate genetic risks characteristic of the Japanese population over the last 2000-3000 years. METHODS: Two genome-wide association studies (GWASs) of 3053 clinically defined gout cases and 4554 controls from Japanese males were performed using the Japonica Array and Illumina Array platforms. About 7.2 million single-nucleotide polymorphisms were meta-analysed after imputation. Patients were then divided into four clinical subtypes (the renal underexcretion type, renal overload type, combined type and normal type), and meta-analyses were conducted in the same manner. Selection pressure analyses using singleton density score were also performed on each subtype. RESULTS: In addition to the eight loci we reported previously, two novel loci, PIBF1 and ACSM2B, were identified at a genome-wide significance level (p<5.0×10-8) from a GWAS meta-analysis of all gout patients, and other two novel intergenic loci, CD2-PTGFRN and SLC28A3-NTRK2, from normal type gout patients. Subtype-dependent patterns of Manhattan plots were observed with subtype GWASs of gout patients, indicating that these subtype-specific loci suggest differences in pathophysiology along patients' gout subtypes. Selection pressure analysis revealed significant enrichment of selection pressure on ABCG2 in addition to ALDH2 loci for all subtypes except for normal type gout. CONCLUSIONS: Our findings on subtype GWAS meta-analyses and selection pressure analysis of gout will assist elucidation of the subtype-dependent molecular targets and evolutionary involvement among genotype, phenotype and subtype-specific tailor-made medicine/prevention of gout and hyperuricaemia.

Review of pediatric abdominal trauma: operative and non-operative treatment in combined adult and pediatric trauma center.

AIM: More than 90% of pediatric solid organ abdominal injuries are treated non-operatively. It remains difficult to decide who should graduate to surgical management, more so if adult physicians must make these decisions on pediatric patients. The purpose of this study was to examine outcomes of all pediatric abdominal trauma cases in a single center, focusing on the decision-making algorithm for operative or non-operative treatment by pediatric and adult physicians. METHODS: We undertook a retrospective review of a pediatric trauma database from April 2006 to March 2016. Groups were divided into operative and non-operative, single or multi-organ injury, and adult or pediatric physician. Operative treatments included laparotomy or interventional radiology procedures. Primary outcome was survival within 30 days. RESULTS: There were 53 abdominal trauma cases; among them, 48 (90.6%) survived and 5 (9.4%) died within 30 days. The probability of survival for mortalities was less than 11%. Forty-two cases were treated non-operatively and 11 operatively. Injury Severity Score was higher in operative group (17 [9, 41]/9 [4, 16.3]). Adult physicians saw 33 patients including seven operative, whereas pediatric physicians saw 20 including four operative cases. There was no statistical difference for the management decision between adult and pediatric physicians. CONCLUSION: Our decisions for intervention were within acceptable rates. Adult physicians did not tend to operate more, but there were cases that did not fit the criteria of the algorithm. Further investigation is needed to look at which factors should be focused on to determine whether or not operative treatments are indicated.

Kinetic analysis of a globin-coupled diguanylate cyclase, YddV: Effects of heme iron redox state, axial ligands, and heme distal mutations on catalysis.

Heme-based oxygen sensors allow bacteria to regulate their activity based on local oxygen levels. YddV, a globin-coupled oxygen sensor with diguanylate cyclase activity from Escherichia coli, regulates cyclic-di-GMP synthesis based on oxygen availability. Stable and active samples of the full-length YddV protein were prepared by attaching it to maltose binding protein (MBP). To better understand the full-length protein's structure, the interactions between its domains were examined by performing a kinetic analysis. The diguanylate cyclase reaction catalyzed by YddV-MBP exhibited Michaelis-Menten kinetics. Its pH optimum was 8.5-9.0, and catalysis required either Mg2+ or Mn2+; other divalent metal ions gave no activity. The most active form of YddV-MBP had a 5-coordinate Fe(III) heme complex; its kinetic parameters were KmGTP 84 ±â€¯21 µM and kcat 1.2 min-1. YddV-MBP with heme Fe(II), heme Fe(II)-O2, and heme Fe(II)-CO complexes had kcat values of 0.3 min-1, 0.95 min-1, and 0.3 min-1, respectively, suggesting that catalysis is regulated by the heme iron's redox state and axial ligand binding. The kcat values for heme Fe(III) complexes of L65G, L65Q, and Y43A YddV-MBP mutants bearing heme distal amino acid replacements were 0.15 min-1, 0.26 min-1 and 0.54 min-1, respectively, implying that heme distal residues play key regulatory roles by mediating signal transduction between the sensing and functional domains. Ultracentrifugation and size exclusion chromatography experiments showed that YddV-MBP is primarily dimeric in solution, with a sedimentation coefficient around 8. The inactive heme-free H93A mutant is primarily octameric, suggesting that catalytically active dimer formation requires heme binding.

Genome-wide association study revealed novel loci which aggravate asymptomatic hyperuricaemia into gout.

OBJECTIVE: The first ever genome-wide association study (GWAS) of clinically defined gout cases and asymptomatic hyperuricaemia (AHUA) controls was performed to identify novel gout loci that aggravate AHUA into gout. METHODS: We carried out a GWAS of 945 clinically defined gout cases and 1003 AHUA controls followed by 2 replication studies. In total, 2860 gout cases and 3149 AHUA controls (all Japanese men) were analysed. We also compared the ORs for each locus in the present GWAS (gout vs AHUA) with those in the previous GWAS (gout vs normouricaemia). RESULTS: This new approach enabled us to identify two novel gout loci (rs7927466 of CNTN5 and rs9952962 of MIR302F) and one suggestive locus (rs12980365 of ZNF724) at the genome-wide significance level (p<5.0×10-8). The present study also identified the loci of ABCG2, ALDH2 and SLC2A9. One of them, rs671 of ALDH2, was identified as a gout locus by GWAS for the first time. Comparing ORs for each locus in the present versus the previous GWAS revealed three 'gout vs AHUA GWAS'-specific loci (CNTN5, MIR302F and ZNF724) to be clearly associated with mechanisms of gout development which distinctly differ from the known gout risk loci that basically elevate serum uric acid level. CONCLUSIONS: This meta-analysis is the first to reveal the loci associated with crystal-induced inflammation, the last step in gout development that aggravates AHUA into gout. Our findings should help to elucidate the molecular mechanisms of gout development and assist the prevention of gout attacks in high-risk AHUA individuals.

Carboxylated phytosterol derivative-introduced liposomes for skin environment-responsive transdermal drug delivery system.

Transdermal drug delivery systems are a key technology for skin-related diseases and for cosmetics development. The delivery of active ingredients to an appropriate site or target cells can greatly improve the efficacy of medical and cosmetic agents. For this study, liposome-based transdermal delivery systems were developed using pH-responsive phytosterol derivatives as liposome components. Succinylated phytosterol (Suc-PS) and 2-carboxy-cyclohexane-1-carboxylated phytosterol (CHex-PS) were synthesized by esterification of hydroxy groups of phytosterol. Modification of phytosterol derivatives on 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) liposomes was confirmed by negatively zeta potentials at alkaline pH and the change of zeta potentials with decreasing pH. In response to acidic pH and temperatures higher than body temperature, Suc-PS-containing and CHex-PS-containing liposomes exhibited content release at intracellular acidic compartments of the melanocytes at the basement membrane of the skin. Phytosterol-derivative-containing liposomes were taken up by murine melanoma-derived B16-F10 cells. These liposomes delivered their contents into endosomes and cytosol of B16-F10 cells. Furthermore, phytosterol-derivative-containing liposomes penetrated the 3 D skin models and reached the basement membrane. Results show that pH-responsive phytosterol-derivative-containing DMPC liposomes are promising for use in transdermal medical or cosmetic agent delivery to melanocytes.

GWAS of clinically defined gout and subtypes identifies multiple susceptibility loci that include urate transporter genes.

OBJECTIVE: A genome-wide association study (GWAS) of gout and its subtypes was performed to identify novel gout loci, including those that are subtype-specific. METHODS: Putative causal association signals from a GWAS of 945 clinically defined gout cases and 1213 controls from Japanese males were replicated with 1396 cases and 1268 controls using a custom chip of 1961 single nucleotide polymorphisms (SNPs). We also first conducted GWASs of gout subtypes. Replication with Caucasian and New Zealand Polynesian samples was done to further validate the loci identified in this study. RESULTS: In addition to the five loci we reported previously, further susceptibility loci were identified at a genome-wide significance level (p<5.0×10-8): urate transporter genes (SLC22A12 and SLC17A1) and HIST1H2BF-HIST1H4E for all gout cases, and NIPAL1 and FAM35A for the renal underexcretion gout subtype. While NIPAL1 encodes a magnesium transporter, functional analysis did not detect urate transport via NIPAL1, suggesting an indirect association with urate handling. Localisation analysis in the human kidney revealed expression of NIPAL1 and FAM35A mainly in the distal tubules, which suggests the involvement of the distal nephron in urate handling in humans. Clinically ascertained male patients with gout and controls of Caucasian and Polynesian ancestries were also genotyped, and FAM35A was associated with gout in all cases. A meta-analysis of the three populations revealed FAM35A to be associated with gout at a genome-wide level of significance (p meta =3.58×10-8). CONCLUSIONS: Our findings including novel gout risk loci provide further understanding of the molecular pathogenesis of gout and lead to a novel concept for the therapeutic target of gout/hyperuricaemia.

The effects of URAT1/SLC22A12 nonfunctional variants, R90H and W258X, on serum uric acid levels and gout/hyperuricemia progression.

Urate transporter 1 (URAT1/SLC22A12), a urate transporter gene, is a causative gene for renal hypouricemia type 1. Among several reported nonsynonymous URAT1 variants, R90H (rs121907896) and W258X (rs121907892) are frequent causative mutations for renal hypouricemia. However, no case-control study has evaluated the relationship between gout and these two variants. Additionally, the effect size of these two variants on serum uric acid (SUA) levels remains to be clarified. Here, 1,993 primary gout patients and 4,902 health examination participants (3,305 males and 1,597 females) were genotyped with R90H and W258X. These URAT1 variants were not observed in any gout cases, while 174 subjects had the URAT1 variant in 2,499 health examination participants, respectively (P = 8.3 × 10(-46)). Moreover, in 4,902 health examination participants, the URAT1 nonfunctional variants significantly reduce the risk of hyperuricemia (P = 6.7 × 10(-19); risk ratio = 0.036 in males). Males, having 1 or 2 nonfunctional variants of URAT1, show a marked decrease of 2.19 or 5.42 mg/dl SUA, respectively. Similarly, females, having 1 or 2 nonfunctional variants, also evidence a decrease of 1.08 or 3.89 mg/dl SUA, respectively. We show that URAT1 nonfunctional variants are protective genetic factors for gout/hyperuricemia, and also demonstrated the sex-dependent effect size of these URAT1 variants on SUA (P for interaction = 1.5 × 10(-12)).

Genome-wide association study of clinically defined gout identifies multiple risk loci and its association with clinical subtypes.

OBJECTIVE: Gout, caused by hyperuricaemia, is a multifactorial disease. Although genome-wide association studies (GWASs) of gout have been reported, they included self-reported gout cases in which clinical information was insufficient. Therefore, the relationship between genetic variation and clinical subtypes of gout remains unclear. Here, we first performed a GWAS of clinically defined gout cases only. METHODS: A GWAS was conducted with 945 patients with clinically defined gout and 1213 controls in a Japanese male population, followed by replication study of 1048 clinically defined cases and 1334 controls. RESULTS: Five gout susceptibility loci were identified at the genome-wide significance level (p<5.0×10(-8)), which contained well-known urate transporter genes (ABCG2 and SLC2A9) and additional genes: rs1260326 (p=1.9×10(-12); OR=1.36) of GCKR (a gene for glucose and lipid metabolism), rs2188380 (p=1.6×10(-23); OR=1.75) of MYL2-CUX2 (genes associated with cholesterol and diabetes mellitus) and rs4073582 (p=6.4×10(-9); OR=1.66) of CNIH-2 (a gene for regulation of glutamate signalling). The latter two are identified as novel gout loci. Furthermore, among the identified single-nucleotide polymorphisms (SNPs), we demonstrated that the SNPs of ABCG2 and SLC2A9 were differentially associated with types of gout and clinical parameters underlying specific subtypes (renal underexcretion type and renal overload type). The effect of the risk allele of each SNP on clinical parameters showed significant linear relationships with the ratio of the case-control ORs for two distinct types of gout (r=0.96 [p=4.8×10(-4)] for urate clearance and r=0.96 [p=5.0×10(-4)] for urinary urate excretion). CONCLUSIONS: Our findings provide clues to better understand the pathogenesis of gout and will be useful for development of companion diagnostics.

Rho-Kinase Inhibition During Early Cardiac Development Causes Arrhythmogenic Right Ventricular Cardiomyopathy in Mice.

OBJECTIVE: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is characterized by fibrofatty changes of the right ventricle, ventricular arrhythmias, and sudden death. Though ARVC is currently regarded as a disease of the desmosome, desmosomal gene mutations have been identified only in half of ARVC patients, suggesting the involvement of other associated mechanisms. Rho-kinase signaling is involved in the regulation of intracellular transport and organizes cytoskeletal filaments, which supports desmosomal protein complex at the myocardial cell-cell junctions. Here, we explored whether inhibition of Rho-kinase signaling is involved in the pathogenesis of ARVC. APPROACH AND RESULTS: Using 2 novel mouse models with SM22α- or αMHC-restricted overexpression of dominant-negative Rho-kinase, we show that mice with Rho-kinase inhibition in the developing heart (SM22α-restricted) spontaneously develop cardiac dilatation and dysfunction, myocardial fibrofatty changes, and ventricular arrhythmias, resulting in premature sudden death, phenotypes fulfilling the criteria of ARVC in humans. Rho-kinase inhibition in the developing heart results in the development of ARVC phenotypes in dominant-negative Rho-kinase mice through 3 mechanisms: (1) reduction of cardiac cell proliferation and ventricular wall thickness, (2) stimulation of the expression of the proadipogenic noncanonical Wnt ligand, Wnt5b, and the major adipogenic transcription factor, PPARγ (peroxisome proliferator activated receptor-γ), and inhibition of Wnt/ß-catenin signaling, and (3) development of desmosomal abnormalities. These mechanisms lead to the development of cardiac dilatation and dysfunction, myocardial fibrofatty changes, and ventricular arrhythmias, ultimately resulting in sudden premature death in this ARVC mouse model. CONCLUSIONS: This study demonstrates a novel crucial role of Rho-kinase inhibition during cardiac development in the pathogenesis of ARVC in mice.

Kinetic Analysis of a Globin-Coupled Histidine Kinase, AfGcHK: Effects of the Heme Iron Complex, Response Regulator, and Metal Cations on Autophosphorylation Activity.

The globin-coupled histidine kinase, AfGcHK, is a part of the two-component signal transduction system from the soil bacterium Anaeromyxobacter sp. Fw109-5. Activation of its sensor domain significantly increases its autophosphorylation activity, which targets the His183 residue of its functional domain. The phosphate group of phosphorylated AfGcHK is then transferred to the cognate response regulator. We investigated the effects of selected variables on the autophosphorylation reaction's kinetics. The kcat values of the heme Fe(III)-OH(-), Fe(III)-cyanide, Fe(III)-imidazole, and Fe(II)-O2 bound active AfGcHK forms were 1.1-1.2 min(-1), and their Km(ATP) values were 18.9-35.4 µM. However, the active form bearing a CO-bound Fe(II) heme had a kcat of 1.0 min(-1) but a very high Km(ATP) value of 357 µM, suggesting that its active site structure differs strongly from the other active forms. The Fe(II) heme-bound inactive form had kcat and Km(ATP) values of 0.4 min(-1) and 78 µM, respectively, suggesting that its low activity reflects a low affinity for ATP relative to that of the Fe(III) form. The heme-free form exhibited low activity, with kcat and Km(ATP) values of 0.3 min(-1) and 33.6 µM, respectively, suggesting that the heme iron complex is essential for high catalytic activity. Overall, our results indicate that the coordination and oxidation state of the sensor domain heme iron profoundly affect the enzyme's catalytic activity because they modulate its ATP binding affinity and thus change its kcat/Km(ATP) value. The effects of the response regulator and different divalent metal cations on the autophosphorylation reaction are also discussed.

Reduction of the Incidence of Delayed Gastric Emptying in Side-to-Side Gastrojejunostomy in Subtotal Stomach-Preserving Pancreaticoduodenectomy.

BACKGROUND: One of the most common morbidities of pancreaticoduodenectomies is delayed gastric emptying (DGE). The recent advent of subtotal stomach-preserving pancreaticoduodenectomy (SSPPD) attempts to lessen this troublesome complication; however, the incidence of DGE still remains to be 4.5-20%. This study aims to evaluate whether the incidence of DGE can be reduced by the side-to-side gastric greater curvature-to-jejunal anastomosis in comparison with the gastric stump-to-jejunal end-to-side anastomosis in SSPPD. METHODS: Between October 2007 and September 2012, a total of 160 consecutive patients who had undergone SSPPD were analyzed retrospectively. In the first period (October 2007-March 2010), gastrojejunostomy was performed with end-to-side anastomosis in 80 patients (SSPPD-ETS group). In the second period (April 2010-September 2012), gastrojejunostomy was performed with the greater curvature side-to-jejunal side anastomosis in 80 patients (SSPPD-STS group). The postoperative data were collected prospectively in a database and reviewed retrospectively. RESULTS: The incidence of DGE was 21.3% in the SSPPD-ETS group and 2.5% in the SSPPD-STS group (P = 0.0002). According to the classification of the International Study Group of Pancreatic Surgery (ISGPS), the incidence of DGE of grades A, B, and C were 5, 5, and 7 in the SSPPD-ETS group and 0, 2, and 0 in the SSPPD-STS group, respectively. The overall morbidity and postoperative hospital stay of the two groups were not significantly different. CONCLUSIONS: The greater curvature side-to-side anastomosis of gastrojejunostomy is associated with a reduced incidence of DGE after SSPPD.