A biomimetic elastomeric robot skin using electrical impedance and acoustic tomography for tactile sensing.

Human skin perceives physical stimuli applied to the body and mitigates the risk of physical interaction through its soft and resilient mechanical properties. Social robots would benefit from whole-body robotic skin (or tactile sensors) resembling human skin in realizing a safe, intuitive, and contact-rich human-robot interaction. However, existing soft tactile sensors show several drawbacks (complex structure, poor scalability, and fragility), which limit their application in whole-body robotic skin. Here, we introduce biomimetic robotic skin based on hydrogel-elastomer hybrids and tomographic imaging. The developed skin consists of a tough hydrogel and a silicone elastomer forming a skin-inspired multilayer structure, achieving sufficient softness and resilience for protection. The sensor structure can also be easily repaired with adhesives even after severe damage (incision). For multimodal tactile sensation, electrodes and microphones are deployed in the sensor structure to measure local resistance changes and vibration due to touch. The ionic hydrogel layer is deformed owing to an external force, and the resulting local conductivity changes are measured via electrodes. The microphones also detect the vibration generated from touch to determine the location and type of dynamic tactile stimuli. The measurement data are then converted into multimodal tactile information through tomographic imaging and deep neural networks. We further implement a sensorized cosmetic prosthesis, demonstrating that our design could be used to implement deformable or complex-shaped robotic skin.

Prior exposure of agriculture cephalosporin ceftiofur impaired conjugation of blaCTX-M-65 gene-bearing plasmid in Salmonella Saintpaul.

AIMS: Although a link between agricultural cephalosporin use and resistance in Salmonella has been demonstrated with the drug ceftiofur, the underlying mechanism of the correlation is unclear. This study investigated the impact of ceftiofur exposure in S. Saintpaul on ceftriaxone resistance, the gene expression and the conjugative transfer of the blaCTX-M-65 gene. METHODS AND RESULTS: Prior ceftiofur exposure caused a twofold increase in MIC from 1024 to 2048 µg ml-1 towards ceftriaxone and increased the enzymatic activity of BlaCTX-M-65 2·2 folds from 3·46 to 7·67 nmol nitrocefin hydrolysed min-1 . A threefold upregulation in gene expression of the blaCTX-M-65 gene was also observed. Donors exposed to ceftiofur subsequently demonstrated a 2·5-fold decrease in transfer efficiency. CONCLUSIONS: Prior exposure of S. Saintpaul to ceftiofur led to increased phenotypic resistance towards ceftriaxone while its ability to spread the cephalosporin resistance through conjugation, conversely, was impaired. SIGNIFICANCE AND IMPACT OF THE STUDY: Findings from this study shed light on one possible mechanism in which agricultural cephalosporin exposure in Salmonella may subsequently impact clinical treatment. The finding that cephalosporin exposure in donors may hinder the subsequent spread of resistance instead of aiding it up was counter-intuitive.

Biofilm formation and disinfectant resistance of Salmonella sp. in mono- and dual-species with Pseudomonas aeruginosa.

AIMS: This study aimed to evaluate the biofilm formation and disinfectant resistance of Salmonella cells in mono- and dual-species biofilms with Pseudomonas aeruginosa, and to investigate the role of extracellular polymeric substances (EPS) in the protection of biofilms against disinfection treatment. METHODS AND RESULTS: The populations of Salmonella in mono- or dual-species biofilms with P. aeruginosa on stainless steel (SS) coupons were determined before and after exposure to commercial disinfectant, 50 µg ml-1 chlorine or 200 µg ml-1 Ecolab® Whisper™ V (a blend of four effective quaternary ammonium compounds (QAC)). In addition, EPS amount from biofilms was quantified and biofilm structures were observed using scanning electron microscopy (SEM). Antagonistic interactions between Salmonella and P. aeruginosa resulted in lower planktonic population level of Salmonella, and lower density in dual-species biofilms compared to mono-species biofilms. The presence of P. aeruginosa significantly enhanced disinfectant resistance of S. Typhimurium and S. Enteritidis biofilm cells for 2 days, and led to an average of 50% increase in polysaccharides amount in dual-species biofilms than mono-species biofilms of Salmonella. Microscopy observation showed the presence of large microcolonies covered by EPS in dual-species biofilms but not in mono-species ones. CONCLUSION: The presence of P. aeruginosa in dual-species culture inhibited the growth of Salmonella cells in planktonic phase and in biofilms, but protected Salmonella cells in biofilms from disinfection treatment, by providing more production of EPS in dual-species biofilms than mono-species ones. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides insights into inter-species interaction, with regard to biofilm population dynamics and disinfectant resistance. Thus, a sanitation protocol should be designed considering the protective role of secondary species to pathogens in biofilms on SS surface which has been widely used at food surfaces and manufacturers.

Antibacterial efficacy of 405, 460 and 520 nm light emitting diodes on Lactobacillus plantarum, Staphylococcus aureus and Vibrio parahaemolyticus.

AIMS: Little information is available on a direct comparison of the antibacterial efficacy of light emitting diode (LEDs) of different peak wavelengths. Thus, the objective of this study was to evaluate the effect of LEDs of three different wavelengths on bacterial inactivation. METHODS AND RESULTS: Lactobacillus plantarum, Staphylococcus aureus and Vibrio parahaemolyticus were illuminated with 405, 460 and 520 nm LEDs at 4, 10 and 25°C respectively. Inactivation curves were plotted and fitted using Gompertz Model. Illumination with 405 and 460 nm LED produced significant inactivation (P < 0·05) in the population of V. parahaemolyticus (>4 log) while Lact. plantarum and Staph. aureus showed relatively less susceptibility to the LED illumination. The 520 nm LED produced negligible inactivation. CONCLUSIONS: The 405 and 460 nm LEDs proved more effective in inactivating the selected foodborne bacteria in this study compared to 520 nm LED. The 405 nm LED showed the greatest antibacterial effect at the same level of energy dose. SIGNIFICANCE AND IMPACT OF THE STUDY: The results in this study demonstrated the antibacterial efficacy of 405 nm LED on Lact. plantarum and V. parahaemolyticus, suggesting its potential for use in food industry for the control of these micro-organisms.

A double-blind randomised controlled trial of fish oil-based versus soy-based lipid preparations in the treatment of infants with parenteral nutrition-associated cholestasis.

BACKGROUND: Infants receiving prolonged parenteral nutrition (PN) are at risk of PN-associated cholestasis (PNAC). This can progress to hepatic failure and death if PN cannot be discontinued. Fish oil-based parenteral lipid preparation (FOLP) has been shown to be beneficial in case studies. OBJECTIVES: (1) To evaluate whether FOLP could halt or reverse the progression of PNAC compared with soy-based parenteral lipid preparation (SLP) and (2) to assess the effects of FOLP on liver function and physical growth. DESIGN: double-blind randomised controlled trial. SETTING: level III neonatal intensive care unit. PARTICIPANTS: infants with PNAC (plasma-conjugated bilirubin concentration ≥ 34 µmol/l or 2 mg/dl) expected to be PN-dependent for >2 weeks. INTERVENTION: to receive either FOLP or SLP at 1.5 g/kg/day. PRIMARY OUTCOME MEASURE: reversal of PNAC within 4 months after commencement of lipid treatment; secondary outcomes: rate of change of weekly liver function tests, infant growth parameters, blood lipid profile and episodes of late-onset sepsis. RESULTS: A total of 9 infants were randomised to the FOLP group and 7 to the SLP group. There was no significant difference in reversal of PNAC at 4 months between groups. Rates of increase of plasma-conjugated bilirubin and alanine aminotransferase in the SLP group were significantly greater than the FOLP group (13.5 vs. 0.6 µmol/l per week and 9.1 vs. 1.1 IU/l per week, respectively, p = 0.03). Increased enteral nutrition was associated with significant improvement of PNAC in infants receiving FOLP compared with SLP (-8.5 vs. -1.6 µmol/l per 10% increase in enteral nutrition, respectively). The study was terminated prematurely. CONCLUSIONS: progression of PNAC in PN-dependent infants can be halted by replacing SLP with FOLP and reversed by increasing the proportion of enteral nutrition in infants receiving FOLP. Replacement of SLP with FOLP in PN-dependent infants who develop PNAC may be considered.

Socioenvironmental factors associated with constipation in Hong Kong children and Rome III criteria.

OBJECTIVE: Data regarding the prevalence of constipation in the general population of Asian children using internationally standardized definitions are scarce. Environmental factors surrounding a child's day to day living may trigger or perpetuate constipation and encourage postponement of defecation. METHODS: A territory-wide cross-sectional questionnaire survey was conducted in 2318 Hong Kong Chinese elementary school students. Constipation was defined by pediatric Rome III criteria. RESULTS: The mean age of the children was 9 ± 1.9 years; 51% were boys. Two hundred eighty-two children (12.2%, 95% confidence interval [CI] 10.9%-13.5%) were found to have constipation. Children ages 6 to 7 years had the highest prevalence (16.8%, 95% CI 13.8%-19.8%). There was no difference in prevalence between boys and girls (11.6% vs 12.3%; P > 0.05) and between obese and nonobese children (11.5% vs 11.1%; P > 0.05). In univariate analysis, constipation was found to be significantly more prevalent among those children who lived with neither parent, had inadequate company of parents at home, refused to pass bowel movements in school, spent long hours doing homework, had inadequate sleep, and had decreased fiber intake and frequent consumption of fast food (P < 0.05). Multivariate analysis identified refusal to pass bowel movements in school toilets (odds ratio [OR] 1.97, 95% CI 1.42%-2.74%), having dinner with one/both parents <50% of time (OR 1.52, 95% CI 1.01%-2.31%), nighttime sleep <7 hours (OR 1.87, 95% CI 1.04%-3.33%), and frequent consumption of fast food (OR 1.14, 95% CI 1.03%-1.26%) to be independent factors associated with constipation. CONCLUSIONS: Socioenvironmental factors are associated with childhood constipation, and bringing them to the awareness of the public may help prevent or stop the progression of childhood constipation at its early stages.

A surgeon-friendly technique to perform single-incision laparoscopic appendectomy intracorporeally in children with conventional laparoscopic instruments.

BACKGROUND: Single-incision laparoscopic appendectomy (SILA) has been successfully performed in children. The intracorporeal approach, using reticulating instruments and 5- to 10-mm ports, has been described in recent reports. In this article, we describe our technique of performing SILA in children, using conventional 3- and 5-mm ports and instruments only. METHODS: We conducted a retrospective review of all consecutive children who underwent SILA over a 3-month period by a standardized technique of using one 3-mm and two 5-mm ports. The procedure was completed intracorporeally by conventional instruments, and the specimen was retrieved without wound contamination by a simple method. RESULTS: Eleven consecutive children (8-14 years), with a mean body weight of 38.5 kg, underwent successful SILA by our technique during the review period. Mean operating time was 83 minutes. There was no conversion to conventional laparoscopic or open appendectomy. Mean postoperative analgesic requirement was 2.4 doses of oral acetaminophen, and no narcotic analgesic was required. All the patients recovered smoothly without complications. CONCLUSIONS: SILA can be safely performed in children when using standard laparoscopic instruments without additional costs in equipment. Using 3- and 5-mm ports seems more appealing to children, with their smaller umbilicus, than adults.

Overt diabetes mellitus adversely affects surgical outcomes of noncardiovascular patients.

BACKGROUND: It is known that cardiac surgical patients with diabetes have greater peri-operative mortality and morbidity when compared with nondiabetic patients; the rate of adverse events in other surgery subspecialties has been only investigated minimally. The aim of this study was to test the magnitude of association between overt diabetes mellitus and postoperative complications across a spectrum of noncardiac surgical patients. METHODS: Prospective outcome data registries describing 1,343 data sets from a spectrum of surgical subspecialties were examined to establish the prevalence of diagnosed diabetes, the incidence of intra- and postoperative complications, and the difference in proportion of morbidity between diabetic versus nondiabetic patients. RESULTS: There was a significant difference in overall morbidity between diabetic and nondiabetic patients with a 2.0 and 1.6 times increased morbidity risk in known diabetic patients with and without malignancy, respectively. Known diabetes was related to the number of postoperative complications in noncardiovascular patients. CONCLUSION: This study quantified the association between known diabetes and the occurrence of complications during recovery after a spectrum of noncardiac surgery. Because of a high prevalence of prediabetic and undiagnosed conditions, the strength of associations between glucose dysregulation and operative outcomes may be even greater than we report.

Rescue treatment of infants with intestinal failure and parenteral nutrition-associated cholestasis (PNAC) using a parenteral fish-oil-based lipid.

Four preterm infants with intestinal failure and severe parenteral nutrition-associated cholestasis (PNAC) received fish-oil-based parenteral lipid as rescue treatment in substitution for the standard soybean-based lipid preparation. The progression of liver disease was halted in 3 infants and they recovered with complete resolution of PNAC. The condition in two of these infants would almost certainly have progressed to end-stage hepatic failure if they had continued to receive long-term parenteral nutrition and <30% of total nutrition enterally. The remaining infant with residual inflamed bowel, protracted feeding intolerance and repeated episodes of sepsis did not respond. Our findings suggest that fish-oil-based parenteral lipid emulsion may contribute to effective treatment of PNAC in selected patients, which should be further evaluated in randomized controlled trials.

Congenital intrathoracic stomach: short esophagus or hiatal hernia?

We present a rare case of congenital intrathoracic stomach due to short esophagus in a preterm infant. Antenatal ultrasound during the second trimester showed a tubular cystic structure in the posterior mediastinum. The diagnosis of congenital hiatal hernia was initially made. After birth, the diagnosis was confirmed to be intrathoracic stomach associated with a congenitally short esophagus by upper gastrointestinal contrast study and laparotomy. Features that suggest intrathoracic stomach secondary to congenital short esophagus over the relatively more common congenital hiatal hernia include early identification of the intrathoracic stomach during the second trimester and the consistent absence of an abdominal stomach bubble on antenatal ultrasound. The infant's condition could not be surgically repaired due to the extremely malformed and short esophagus and she subsequently died. This is in sharp contrast to the more surgically amenable and non-life-threatening congenital hiatal hernia. Early recognition of intrathoracic stomach associated with congenital short esophagus is important as it is associated with difficult management and significant postnatal complications. Fetal magnetic resonance imaging may be useful in this situation. The prognosis is cautiously guarded, and the parents should be appropriately counseled.

Familial extrarenal Wilms tumor.

BACKGROUND/PURPOSE: This study aimed to illustrate the first report of extrarenal Wilms tumor occurring in a family. MATERIALS AND METHODS: Retrospective case note review of 3 siblings, 2 of which presented with extrarenal Wilms tumor. Immunohistochemical analysis for WT1 gene product was performed together with molecular genetic linkage studies. RESULTS: A 3-year-old boy had excision of a right-sided extrarenal retroperitoneal Wilms tumor and nephrectomy followed by chemotherapy. At follow-up of 4 years, the boy was well and thriving. Aged 2 years, his sister developed a left-sided retroperitoneal extrarenal Wilms tumor. She had a tumor excision and nephrectomy followed by chemotherapy. She was well on follow-up more than a year after completion of treatment. Immunohistochemical analysis identified WT1 gene product within the tumor for both cases. Molecular genetic linkage studies showed no linkage between the index cases at FWT1 locus. Although possible linkage was demonstrated at WT1 locus, no mutation was found in the coding sequence and intron/exon boundaries of WT1 gene in index patient 1. A possible linkage between the index cases was also found at FWT2 locus. This could be a chance event because of the close relationship of the 2 patients. CONCLUSIONS: We could identify extrarenal Wilms tumor in a family for the first time. Immunohistochemical analysis showed WT1 gene products in both cases. Linkage studies for Wilms tumor genes within the family were inconclusive. The possible linkage between the 2 index cases may be a chance event.

Minimally invasive approach in the management of childhood intussusception.

BACKGROUND: Intussusception is one of the most common causes of intestinal obstruction in infancy. Non-operative reduction using air enema or other hydrostatic reduction methods has been the standard treatment in most cases. However, if the non-operative method is not indicated or fails, open surgery is still necessary. With the tremendous development of the minimally invasive approach in handling surgical conditions in children in the last decade, this has been applied recently for the reduction of intussusception in children. We herein reviewed our experience of using the combined approach, namely, pneumatic reduction and, if failed, laparoscopic reduction in the management of childhood intussusception. METHODS: We carried out a retrospective analysis of all children with intussusception managed at Prince of Wales Hospital between December 1998 and December 2004. The minimally invasive approach was used as far as possible. The method of reduction, success rate and the incidence of complication were analysed. RESULTS: Over a 6-year period, there were 146 patients with 167 episodes of intussusception. Pneumatic reduction was carried out in 160 occasions and was successful in 134 (83.8%). In 33 patients, operative reduction was required. Of these, laparoscopic reduction was attempted in 15 and was successful in 13 (86.7%). In those with either pneumatic or laparoscopic reduction, no procedure-related complication was encountered and they had a significant shorter hospital stay (median 3.0 day) than those requiring laparotomy (median 8.0 day) (t-test, P < 0.0001). CONCLUSION: The minimally invasive approach, that is, pneumatic and/or laparoscopic reduction, was successful in reducing intussusception in 88% of patients with minimal morbidity and shorter hospital stay.

Adaptation of Salmonella spp. in juice stored under refrigerated and room temperature enhances acid resistance to simulated gastric fluid.

The objective of this study was to evaluate the acid resistance of Salmonella spp. adapted in juices stored under refrigeration and room temperatures to simulated gastric fluid (SGF, pH 1.5). Five Salmonella serovars, Agona, Gaminara, Michigan, Montevideo, and Poona were used in this study. Apple, orange, and tomato juices inoculated with five serovars were stored at refrigeration (7 degrees C) and room temperature (20 degrees C) for 24 h for adaptation. Acid resistances of serovars adapted in juice were determined in SGF at 37 degrees C. All acid-adapted Salmonella serovars in juices displayed enhanced survival time compared to non-adapted controls. Among serovars, S. Poona adapted in apple at 20 degrees C and orange juices at 7 and 20 degrees C showed >2.0 log cfu/ml survivors, while the other serovars decreased to non-detectable level or <2.0 log cfu/ml for 100 s in SGF. Unlike apple and orange juices, all serovars adapted in tomato juice survived with >2.0 log cfu/ml for 100 s. For D-values, all Salmonella serovars adapted in apple and tomato juice enhanced their acid resistances compared to orange juices. S. Agona adapted in tomato juice at 7 degrees C and S. Poona in apple juice at 20 degrees C had the highest D-values with 82.9 and 82.5s, respectively. Results showed that the adaptation in juice increased acid resistance in SGF and varied by serovar, juice type, and adaptation temperature. Therefore, this study indicates that the introduction of Salmonella spp. to an acidic juice environment during processing can enhance their ability to survive in a human stomach, possibly increasing the risk of a Salmonella outbreak by juice.