Preoperative Progressive Pneumoperitoneum in the Treatment of Hernias With Loss of Domain. Our Experience in 50 Cases.

Introduction: Surgical planning for repair of giant hernias with loss of domain needs to consider patient comorbidities, potential risks and possible postoperative complications. Some postoperative complications are related to the increase in intra-abdominal pressure caused by the reintroduction of abdominal contents into the peritoneal space. Preoperative progressive pneumoperitoneum (PPP) increases the capacity of abdominal cavity prior to hernia repair and allows for better physiological postoperative adaptation. The aim of this study is to analyze perioperative and intraoperative characteristics as well as outcomes of a cohort of patients treated with PPP prior to giant hernia repair at a single, high volume center. Methods: Prospective, descriptive, observational single-center study including 50 patients undergoing PPP prior to hernia with loss of domain repair between January 2005 and June 2022. We analysed epidemiological, surgical and safety variables. Results: Fifty patients were included: 43 incisional hernias, 6 inguinal hernias and 1 umbilical hernia. Mean age was 66 years (36-85). Median insufflation time was 12 days (4-20) and median insufflated volume of ambient air was 10,036 cc. There were complications during PPP in nine patients: 2 decompensation of chronic respiratory disease and 7 subcutaneous emphysema. PPP was prematurely suspended in patients with respiratory decompensation. All patients with incisional and umbilical hernias underwent open repair with mesh placement. Preperitoneal repair was performed in inguinal hernias. Three cases of hernia recurrence were reported during the follow up. Conclusion: PPP is a safe and effective tool in the preoperative management of patients with giant hernias. It helps to achieve the decrease or absence of abdominal wall tension and can favour the results of complex eventroplasty techniques.

In Situ Monitoring and Quantitative Determination of R27 Plasmid Conjugation.

Horizontal gene transfer (HGT) by plasmid conjugation is a major driving force in the spread of antibiotic resistance among Enterobacteriaceae. Most of the conjugation studies are based on calculation of conjugation ratios (number of transconjugants/number of donors) after viable counting of transconjugant and donor cells. The development of robust, fast and reliable techniques for in situ monitoring and quantification of conjugation ratios might accelerate progress in understanding the impact of this cellular process in the HGT. The IncHI1 plasmids, involved in multiresistance phenotypes of relevant pathogens such as Salmonella and E. coli, are distinguished by the thermosensitivity of their conjugative transfer. Conjugation mediated by IncHI1 plasmids is more efficient at temperatures lower than 30 °C, suggesting that the transfer process takes place during the environmental transit of the bacteria. In this report, we described a methodology to monitor in situ the conjugation process during agar surface matings of the IncHI1 plasmid R27 and its derepressed derivative drR27 at different temperatures. A three-color-labeling strategy was used to visualize the spatial distribution of transconjugants within the heterogeneous environment by epifluorescence and confocal microscopy. Moreover, the fluorescent labelling was also used to quantify conjugation frequencies in liquid media by flow cytometry.

Phage-Mediated Explosive Cell Lysis Induces the Formation of a Different Type of O-IMV in Shewanella vesiculosa M7T.

Shewanella vesiculosa M7T is a cold-adapted Antarctic bacterium that has a great capacity to secrete membrane vesicles (MVs), making it a potentially excellent model for studying the vesiculation process. S. vesiculosa M7T undergoes a blebbing mechanism to produce different types of MVs, including outer membrane vesicles and outer-inner membrane vesicles (O-IMVs). More recently, other mechanisms have been considered that could lead to the formation of O-IMVs derived from prophage-mediated explosive cell lysis in other bacteria, but it is not clear if they are of the same type. The bacterial growth phase could also have a great impact on the type of MVs, although there are few studies on the subject. In this study, we used high-resolution flow cytometry, transmission electron microscopy, and cryo-electron microscopy (Cryo-EM) analysis to determine the amount and types of MVs S. vesiculosa M7T secreted during different growth phases. We show that MV secretion increases during the transition from the late exponential to the stationary phase. Moreover, prophage-mediated explosive cell lysis is activated in S. vesiculosa M7T, increasing the heterogeneity of both single- and double-layer MVs. The sequenced DNA fragments from the MVs covered the entire genome, confirming this explosive cell lysis mechanism. A different structure and biogenesis mechanisms for the explosive cell lysis-derived double-layered MVs was observed, and we propose to name them explosive O-IMVs, distinguishing them from the blebbing O-IMVs; their separation is a first step to elucidate their different functions. In our study, we used for the first time sorting by flow cytometry and Cryo-EM analyses to isolate bacterial MVs based on their nucleic acid content. Further improvements and implementation of bacterial MV separation techniques is essential to develop more in-depth knowledge of MVs.

Gut Bacterial Community of the Xylophagous Cockroaches Cryptocercus punctulatus and Parasphaeria boleiriana.

Cryptocercus punctulatus and Parasphaeria boleiriana are two distantly related xylophagous and subsocial cockroaches. Cryptocercus is related to termites. Xylophagous cockroaches and termites are excellent model organisms for studying the symbiotic relationship between the insect and their microbiota. In this study, high-throughput 454 pyrosequencing of 16S rRNA was used to investigate the diversity of metagenomic gut communities of C. punctulatus and P. boleiriana, and thereby to identify possible shifts in symbiont allegiances during cockroaches evolution. Our results revealed that the hindgut prokaryotic communities of both xylophagous cockroaches are dominated by members of four Bacteria phyla: Bacteroidetes, Firmicutes, Proteobacteria, and Actinobacteria. Other identified phyla were Spirochaetes, Planctomycetes, candidatus Saccharibacteria (formerly TM7), and Acidobacteria, each of which represented 1-2% of the total population detected. Community similarity based on phylogenetic relatedness by unweighted UniFrac analyses indicated that the composition of the bacterial community in the two species was significantly different (P < 0.05). Phylogenetic analysis based on the characterized clusters of Bacteroidetes, Spirochaetes, and Deltaproteobacteria showed that many OTUs present in both cockroach species clustered with sequences previously described in termites and other cockroaches, but not with those from other animals or environments. These results suggest that, during their evolution, those cockroaches conserved several bacterial communities from the microbiota of a common ancestor. The ecological stability of those microbial communities may imply the important functional role for the survival of the host of providing nutrients in appropriate quantities and balance.

On-demand endoscopic CO2 insufflation with feedback pressure regulation during natural orifice transluminal endoscopic surgery (NOTES) peritoneoscopy induces minimal hemodynamic and respiratory changes.

BACKGROUND: Endoscopic insufflation has been associated with marked increase in intra-abdominal pressure (IAP) and hemodynamic and respiratory changes during transgastric surgery. OBJECTIVE: To investigate the hemodynamic and respiratory effects during intraperitoneal cavity exploration through 3 different natural orifice transluminal endoscopic surgery (NOTES) access locations compared with laparoscopy. DESIGN AND SETTING: Survival experiments using 40 female pigs randomized to transgastric, transcolonic, transvaginal, and laparoscopic peritoneoscopy. INTERVENTIONS: On-demand endoscopic insufflation of CO(2) with feedback pressure regulation was used in NOTES with a maximum pressure of 14 mm Hg. In the laparoscopy group, the IAP was maintained at 14 mm Hg. NOTES procedures were performed by an endoscopist (with the assistance of a gynecologist in the transvaginal group and a second endoscopist in the transgastric and transrectal groups) and laparoscopy by 2 surgeons. MAIN OUTCOME MEASUREMENTS: Invasive hemodynamic and respiratory data. Blood samples were drawn for gas analyses. RESULTS: All experiments except one in the transrectal group were completed. The IAP was significantly lower in all NOTES groups compared with the laparoscopy group. A significant increase in mean systemic arterial blood pressure was observed in the laparoscopy group at 15 and 30 minutes of intraperitoneal cavity exploration, but it remained unchanged during all NOTES procedures. An increase in airway pressures was observed at 15 and 30 minutes of peritoneoscopy in the animals undergoing laparoscopy, whereas those parameters remained unchanged in the NOTES groups. The laparoscopy group showed a significant impairment in pulmonary gas exchange (decrease in Pao(2), increase in Paco(2), and decrease in arterial pH) after 30 minutes of peritoneoscopy, whereas only a slight increase in Paco(2) was observed in the transrectal and transvaginal groups. LIMITATIONS: Healthy animal model. CONCLUSION: On-demand endoscopic insufflation of CO(2) with feedback pressure regulation can minimize the risk of hemodynamic and respiratory compromise caused by acute changes in IAP.

Gastric emptying is delayed in transgastric NOTES: a randomized study in swine.

AIM: The aim of this study was to evaluate the restoration of gastrointestinal motility after NOTES using capsule endoscopy (CE). MATERIALS AND METHODS: Twenty adult Yorkshire pigs were randomly assigned to four groups: transgastric NOTES (gNOTES), transrectal NOTES (rNOTES), transvaginal NOTES (vNOTES), and laparoscopy (LAP). At the end of a 30-min peritoneoscopy with identification of seven predetermined organs, an array of eight receivers and the recorder were attached to the abdominal wall. The CE was delivered into the antrum with the help of an endoscope and a polypectomy snare. Animals were kept alive for 14 d. RESULTS: Median time for surgery was longer in gNOTES (56 min, range 47-63) and vNOTES (54 min, range 44-79) than in LAP (32 min, range 32-33; P < 0.05 and P < 0.01) and in rNOTES (45.5 min, range 33-56) (P = ns). This increase was related to a larger incision and longer closure times. Images from the CE were successfully retrieved in 19 cases. The CE was retained in the stomach in all animals in gNOTES (459 min; range 360-600), but only in one animal in rNOTES and vNOTES and in none in the LAP group. Failure of passage of the CE beyond the stomach was associated with gNOTES and longer closure of the incision. Animals in the gNOTES group gained less weight than the others and this change was statistical significant when compared with vNOTES animals (1.7 kg, range -1.98 to 4.5 versus 8.4 kg, range 5.8 to 11.45; P < 0.01). CONCLUSION: Gastric emptying is delayed after gNOTES peritoneoscopy compared with rNOTES, vNOTES, and LAP and this effect is associated with less weight gain.

Inflammatory impact of NOTES peritoneoscopy is not different from that of laparoscopy: a randomized comparative study in a survival porcine model.

BACKGROUND: Inflammatory changes of different NOTES approaches remain unknown. The aim of this study was to compare the inflammatory effects of NOTES and laparoscopy. METHODS: Forty female pigs were assigned to transgastric, transrectal, and transvaginal NOTES and laparoscopic peritoneoscopy groups. Antiseptic technique was utilized for NOTES whereas laparoscopy was performed sterile. Intraperitoneal pressures were monitored and maintained below 15 mmH(2)O. Pneumoperitoneum was maintained with CO(2) in all groups. Pre- and postoperative blood samples of IL-6, Il-1ß, and TNFα, and peritoneal fluid collected at surgery were analyzed. Animals were followed daily for 14 days. At necropsy, peritoneal fluid was collected for cytokine analysis. RESULTS: Thirty-nine peritoneoscopies were successfully completed. The median procedure time was longer in the NOTES groups (57 min, range = 33-109) than in the laparoscopy group (33 min, range 32-36; P < 0.001); this was related to longer incision time and closure time. All 39 completed follow-up. Severe bleeding in the post-transrectal approach required early sacrifice of the remaining animal. Besides this, complications were similar among groups. At necropsy, adhesions were seen in four animals in the gastric group, five in the rectal group, two in the vaginal group, and two in the laparoscopic group (P = ns). There were no statistical differences in serum levels of TNFα among the groups. When serum TNFα values were expressed as the difference from the baseline, in the transvaginal group they were significantly lower than in the transrectal at 2 h [0.5 pg/ml (range = -14 to 59) vs. 60 pg/ml (range = -8 to 303); P = 0.041] and at 8 h [-5.5 pg/ml (range = -86 to 55] vs. 37 pg/ml (range = -30 to 62); P = 0.031]. The limitations of this study were that the analyses of IL-6 and Il-1ß were not possible because most of the samples were below detectable levels, it was an animal model, and the sample size was small. CONCLUSION: Inflammatory parameters are similar between NOTES and laparoscopic peritoneoscopy despite longer surgery time in the NOTES group. The vaginal route seems to reduce the inflammatory stress.

Infection during natural orifice transluminal endoscopic surgery peritoneoscopy: a randomized comparative study in a survival porcine model.

BACKGROUND: Infection in natural orifice transluminal endoscopic surgery (NOTES) remains controversial. OBJECTIVE: To estimate the frequency of infection during NOTES peritoneoscopy with different routes of access and to compare with laparoscopy. DESIGN: Prospective randomized controlled study (Canadian Classification type I). METHODS: Forty female pigs were randomly assigned to 3 NOTES (transgastric, transrectal, and transvaginal) and laparoscopic groups. Antiseptic technique was used for NOTES, whereas laparoscopy was performed in a sterile environment. Preoperative and postoperative intravenous antibiotics were administered. Closure of the transluminal access site was performed in all animals. Peritoneal fluid was collected for culture at the end of surgery and at necropsy at day 14. RESULTS: Thirty-nine peritoneoscopies were successfully completed. Necropsy confirmed complete healing of NOTES incisions, but 2 animals in the laparoscopy group had small abscesses in the abdominal incisions. There were no statistical differences in the presence of peritoneal adhesions. Positive culture results were seen in all groups at the end of the procedure and in all animals at necropsy, but this did not lead to clinical signs of gross infection. The most common organisms that colonized the peritoneum were gram-positive cocci and gram-negative bacilli from the normal swine gastrointestinal flora. LIMITATIONS: Animal model and small sample size. CONCLUSIONS: In these small series of animals and with the careful lavage and preparation used, NOTES appeared to be comparable to laparoscopy in terms of peritoneal contamination and clinical infection. Despite the adherence to a strict antiseptic protocol, peritoneal contamination occurs but does not lead to septic complications in the swine.

Prognostic factors and time-related changes influence results of colorectal liver metastases surgical treatment: a single-center analysis.

AIM: To analyze the prognostic factors involved in survival and cancer recurrence in patients undergoing surgical treatment for colorectal liver metastases (CLM) and to describe the effects of time-related changes on survival and recurrence in these patients. METHODS: From January 1994 to January 2006, 236 patients with CLM underwent surgery with the aim of performing curative resection of neoplastic disease at our institution and 189 (80%) of these patients underwent resection of CLM with curative intention. Preoperative, intraoperative and postoperative data, including primary tumor and CLM pathology results, were retrospectively reviewed. Patients were divided into two time periods: a first period from January 1994 to January 2000 (n = 93), and a second period from February 2000 to January 2006 (n = 143). RESULTS: Global survival at 1, 3 and 5 years in patients undergoing hepatic resection was 91%, 54% and 47%, respectively. Patients with preoperative extrahepatic disease, carcinoembryonic antigen (CEA) levels over 20 ng/dL, more than four nodules or extrahepatic invasion at pathological analysis had worse survival. Tumor recurrence rate at 1 year was 48.3%, being more frequent in patients with preoperative and pathological extrahepatic disease and CEA levels over 20 ng/dL. Although patients in the second time period had more adverse prognostic factors, no differences in overall survival and recurrence were observed between the two periods. CONCLUSION: Despite advances in surgical technique and better adjuvant treatments and preoperative imaging, careful patient staging and selection is crucial to continue offering a chance of cure to patients with CLM.

[Organ-preserving resection of the pancreaticoduodenal region in the treatment of intraductal papillary mucinous tumors]. / Resección conservadora de la región duodenopancreática en el tratamiento del tumor papilar mucinoso intraductal.

INTRODUCTION: The standard surgical procedure for intraductal papillary mucinous neoplasms of the main duct (IPMN-M) or side branch ducts (IPMN-Br) is pancreaticoduodenectomy. IPMN-BR is a more indolent disease with a lower incidence of malignancy. OBJECTIVE: To evaluate the usefulness of organ-preserving pancreatic resections (OPPR) including duodenum-preserving pancreatic head resection (DPHR) and pancreatic head resection with segmental duodenectomy (PHRSD) in patients with IPMN-BR. PATIENTS AND METHOD: Surgical outcomes were evaluated in eight IPMN-Br patients: DPHR was performed in 4 patients and PHRSD was performed in 4 patients. In addition, 13 IPMN patients with Whipple resections were included in the analysis. RESULTS: The incidence of postoperative complications was 38% after Whipple resection, 100% after DPHR and 25% after PHRSD. The mean length of hospital stay was 27 days after DPHR, 22 days after Whipple resection and 16 days after PHRSD. Invasive IPMN was found in 38% of the patients in the Whipple group, and noninvasive IPMN was found in 100% of patients who underwent organ-preserving surgery. CONCLUSIONS: Pancreaticoduodenectomy remains the treatment of choice in patients with invasive IPMN. PHRSD appears to be a useful procedure for IPMN-Br located in the head of the pancreas.

Resección conservadora de la región duodenopancreática en el tratamiento del tumor papilar mucinoso intraductal / Organ-preserving resection of the pancreaticoduodenal region in the treatment of intraductal papillary mucinous tumors

Introducción. La técnica quirúrgica estándar para el tratamiento del tumor mucinoso papilar intraductal (TPMI) de las variedades del conducto dilatado (TPMI-CD) o ramificado (TPMI-R) es la duodenopancreatectomía cefálica (DPC). El TPMI-R tiene un crecimiento lento y con menor incidencia de malignidad. Objetivo. Evaluar la utilidad de la cirugía conservadora, resección parcial de la cabeza pancreática con preservación duodenal (RPCP-PD), y la resección total de la cabeza pancreática con duodenectomía segmentaria (RTCP-DS) en pacientes con TPMI-R. Pacientes y método. Los resultados de la cirugía fueron evaluados en 8 pacientes, de los que a 4 se realizó la técnica RTCP-PD y a 4, la técnica RTCP-DS. También se incluyó a 13 pacientes a los que se realizó la DPC según técnica de Whipple. Resultados. La incidencia de complicaciones postoperatorias fue del 38% después de Whipple, el 100% después de RPCP-PD y el 25% después de RTCP-DS. La estancia hospitalaria media fue 27 días después de RPCP-PD, 22 días después de Whipple y 16 días después de RTCP-DS. Un TPMI invasivo se encontró en el 38% después de Whipple y un TPMI no invasivo, en el 100% de los pacientes sometidos a cirugía conservadora. Conclusiones. La DPC es la técnica de elección para pacientes con TPMI invasivo. La RTCP-DS parece ser un procedimiento seguro y de gran eficacia en el tratamiento de pacientes con TPMI-R localizado en la cabeza del páncreas (AU)

Introduction. The standard surgical procedure for intraductal papillary mucinous neoplasms of the main duct (IPMN-M) or side branch ducts (IPMN-Br) is pancreaticoduodenectomy. IPMN-BR is a more indolent disease with a lower incidence of malignancy. Objective. To evaluate the usefulness of organ-preserving pancreatic resections (OPPR) including duodenum-preserving pancreatic head resection (DPHR) and pancreatic head resection with segmental duodenectomy (PHRSD) in patients with IPMN-BR. Patients and method. Surgical outcomes were evaluated in eight IPMN-Br patients: DPHR was performed in 4 patients and PHRSD was performed in 4 patients. In addition, 13 IPMN patients with Whipple resections were included in the analysis. Results. The incidence of postoperative complications was 38% after Whipple resection, 100% after DPHR and 25% after PHRSD. The mean length of hospital stay was 27 days after DPHR, 22 days after Whipple resection and 16 days after PHRSD. Invasive IPMN was found in 38% of the patients in the Whipple group, and noninvasive IPMN was found in 100% of patients who underwent organ-preserving surgery. Conclusions. Pancreaticoduodenectomy remains the treatment of choice in patients with invasive IPMN. PHRSD appears to be a useful procedure for IPMN-Br located in the head of the pancreas (AU)

Comparative study of the antimicrobial activity of bis(Nalpha-caproyl-L-arginine)-1,3-propanediamine dihydrochloride and chlorhexidine dihydrochloride against Staphylococcus aureus and Escherichia coli.

OBJECTIVES: The aim of this study is to gain insight into the mechanism of the antimicrobial action of a novel arginine-based surfactant, bis(N(alpha)-caproyl-L-arginine)-1,3-propanediamine dihydrochloride [C(3)(CA)(2)]. METHODS: To this end, we compared its effects against Staphylococcus aureus and Escherichia coli with those caused by the commercial and widely known antiseptic, chlorhexidine dihydrochloride (CHX). RESULTS: Both disrupted the cell membrane of the target bacteria to cause potassium leakage and morphological damage. The effect of C(3)(CA)(2) on E. coli was concentration dependent, causing loss of membrane potential and membrane integrity leading to cell death, whereas CHX did not have these effects on E. coli. The effect of C(3)(CA)(2) on S. aureus was the formation of mesomes and cytoplasmic clear zones, but the loss of membrane potential and membrane integrity was slightly lower than that with CHX. CONCLUSIONS: We propose that C(3)(CA)(2) acts preferentially against Gram-negative bacteria through strong initial binding to the surface lipopolysaccharides and subsequently partitioning into the cell membrane to cause membrane damage, followed by cell death.

Detection of infectious rotaviruses by flow cytometry.

Human rotaviruses are considered the main cause of viral gastroenteritis in infants and young children throughout the world. Their transmission is through the fecal-oral route, mostly after ingestion of contaminated water and food. Since an extremely high number of virus particles are present in the feces during the acute gastroenteritis, methods based on electron microscopy, passive particle agglutination tests, or enzyme-linked immunosorbent assays are readily employed for clinical diagnosis. However, the sensitivity of these procedures is not high enough to detect the low number of viral particles sometimes present in the environment. In the case of environmental samples, amplification of viral nucleic acids by polymerase chain reaction assays coupled to reverse transcription (RT-PCR) has been increasingly applied to detect rotaviruses in water and shellfish samples. However, procedures based on molecular approaches have to face the drawback that they do not differentiate between infectious and noninfectious particles, which is of major relevance from the public health point of view. Virus propagation in cell culture prior to detection by immunological or molecular procedures accomplishes the dual purpose of increasing the amount of target material and incorporating an infectivity assay as well.Wild-type rotaviruses present difficulties in their in vitro replication, although some of them may be adapted to grow in several cell lines such as the monkey kidney cell line MA104 or the human intestinal cell line CaCo-2. More than a decade ago, an assay for the specific detection of infectious rotaviruses in environmental samples, involving an indirect immunofluorescence test (IIF) and optical microscopy (OM) counting of infected foci in infected MA-104 cell monolayers, was described. On the other hand, CaCo-2 cells have been successfully employed in our laboratory for infectivity assays of several fastidious enteric virus strains present in water samples.