Inducible nitric oxide synthase (iNOS) and nitric oxide (NO) are important mediators of reflux-induced cell signalling in esophageal cells.

Nitric oxide (NO) produced by inducible nitric oxide synthase (iNOS) has been implicated in both DNA damage induction and aberrant cell signalling in various tissue and cell backgrounds. We investigated here the role of iNOS and NO in DNA damage induction and nuclear factor-kappa B (NF-κB) signalling in esophageal cells in vitro. As esophageal adenocarcinoma develops in a background of Barrett's esophagus secondary to reflux disease, it is possible that inflammatory mediators like NO may be important in esophageal cancer development. We show that reflux components like stomach acid and bile acids [deoxycholic acid (DCA)] can induce iNOS gene and protein expression and produce NO generation in esophageal cells, using real-time PCR, western blotting and NO sensitive fluorescent probes, respectively. This up-regulation of iNOS expression was not dependent on NF-κB activity. DCA-induced DNA damage was independent of NF-κB and only partially dependent on iNOS and NO, as measured by the micronucleus assay. These same reflux constituents also activated the oncogenic transcription factor NF-κB, as measured by transcription factor enzyme-linked immunosorbent assay and gene expression studies with NF-κB linked genes (e.g. interleukin-8). Importantly, we show here for the first time that basal levels of NF-κB activity (and possibly acid and DCA-induced NF-κB) are dependent on iNOS/NO and this may lead to a positive feedback loop whereby induced iNOS is upstream of NF-κB, hence prolonging and potentially amplifying this signalling, presumably through NO activation of NF-κB. Furthermore, we confirm increased protein levels of iNOS in esophageal adenocarcinoma and, therefore, in neoplastic development in the esophagus.

Laparoscopic single-site surgery for placement of an adjustable gastric band: initial experience.

BACKGROUND: Laparoendoscopic single-site (LESS) surgery for cholecystectomy and appendectomy are described in the literature. The benefits of these procedures compared with traditional laparoscopic approaches have yet to be determined. To date, no series of LESS surgeries for placement of an adjustable gastric band has been published or documented. This study aimed to determine the safety and feasibility of LESS surgery for placement of an adjustable gastric band. METHODS: From December 2007 to June 2008, LESS surgery to place an adjustable gastric band via a transumbilical incision was performed for 10 patients with institutional review board approval. Essentially, multiple ports were placed through a single incision in the umbilicus to allow for liver retraction, visualization, and working instruments. All critical steps using a standard pars flaccida technique were performed without alteration. RESULTS: For this study, 10 patients (9 women and 1 man) were carefully selected. These patients ranged in age from 32 to 61 years (mean, 47 years) and had a mean body mass index (BMI) of 42 kg/m2 (range, 35-45 kg/m2). The patients were selected for absence of both hepatomegaly and central obesity. Superobese patients were not considered for inclusion in the study. The mean operative time was 1 h and 10 min (range, 53 min to 1 h and 48 min). All the patients were discharged home within 23 h of admission, and no perioperative complications were noted. In addition, no wound-related complications occurred. Notably, only 2 of the 10 patients required the use of narcotic analgesia after discharge from the recovery room. There were no intra- or postoperative complications. CONCLUSIONS: In our experience, LESS surgery for adjustable gastric banding shows this technique to be both feasible and safe for selected patients. Although technical limitations exist that will be improved upon, further studies are needed to compare LESS surgery for placement of an adjustable gastric band with traditional laparoscopic techniques.

Experimental comparison of ketamine with a combination of ketamine, butorphanol and medetomidine for general anaesthesia of the Eurasian badger (Meles meles L.).

The refinement of anaesthetic regimes is central to improving the welfare of captured wildlife. The Eurasian badger (Meles meles) has been the subject of an intensive long-term ecological and epidemiological study at Woodchester Park, Gloucestershire, England. During routine trapping operations (June 21st, 2000-January 23rd, 2001) an experimental trial was conducted on 89 badgers to compare the physiological effects of anaesthesia using ketamine hydrochloride alone, and in conjunction with medetomidine hydrochloride and butorphanol tartrate. The mixture induced a significantly longer period of anaesthesia, and either substantially reduced or eliminated the adverse effects associated with ketamine anaesthesia (e.g., excessive salivation, bouts of sneezing, rough recoveries, and muscle rigidity). In a sub-sample of badgers given the mixture, anaesthesia was reversed using atipamezole hydrochloride. Under ketamine anaesthesia, heart rates were initially significantly higher and respiration rates were consistently higher, than in badgers given the mixture. In all badgers heart rates declined and respiration rates increased during anaesthesia, but the rate of change was greatest in animals given only ketamine. Overall, the mixture provided a more balanced anaesthesia characterised by muscle relaxation and complete unconsciousness.

Screening badgers (Meles meles) for Mycobacterium bovis infection by using multiple applications of an ELISA.

The current indirect ELISA used to evaluate whether live badgers are infected with Mycobacterium bovis has a low sensitivity (40.7 per cent), but a relatively high specificity (94.3 per cent). The low sensitivity of the test makes the diagnosis unreliable, but its sensitivity can be increased by using multiple tests. Two multiple testing procedures (involving up to three sequential tests) were investigated. A procedure in which two positive results were required from three tests before an animal was declared positive resulted in a lower sensitivity, but a higher specificity than the single test (38 and 98 per cent respectively). A more rigorous procedure, in which only one positive result was required from three tests, resulted in a marked increase in sensitivity but a slight reduction in specificity (79.5 and 83.1 per cent respectively) when compared to the single test.

Spatial patterns in abundance of a damselfish reflect availability of suitable habitat.

For species with metapopulation structures, variation in abundance among patches can arise from variation in the input rate of colonists. For reef fishes, variability in larval supply frequently is invoked as a major determinant of spatial patterns. We examined the extent to which spatial variation in the amount of suitable habitat predicted variation in the abundance of the damselfish Dascyllus aruanus, an abundant planktivore that occupies live, branched coral throughout the Indo-Pacific. Reef surveys established that size, branching structure and location (proximity to sand) of the coral colonies together determined the "suitability" of microhabitats for different ontogenetic stages of D. aruanus. Once these criteria were known, patterns of habitat use were quantified within lagoons of five Pacific islands. Availability of suitable habitat generally was an excellent predictor of density, and patterns were qualitatively consistent at several spatial scales, including among different lagoons on the same island, among different islands and between the central (French Polynesia and Rarotonga) and western (Great Barrier Reef, Australia) South Pacific. A field experiment that varied the amount of suitable coral among local plots indicated that habitat for settlers accounted for almost all of the spatial variation in the number of D. aruanus that settled at that location, suggesting that spatial patterns of abundance can be established at settlement without spatial variation in larval supply. Surveys of four other species of reef-associated fish revealed that a substantial fraction of their spatial variation in density also was explained by availability of suitable reef habitat, suggesting that habitat may be a prevalent determinant of spatial patterns. The results underscore the critical need to identify accurately the resource requirements of different species and life stages when evaluating causes of spatial variation in abundance of reef fishes.

Auditory verbal learning test components as measures of the severity of closed-head injury.

Auditory verbal learning and memory was assessed in 18 patients with moderate-severe closed-head injury (CHI). Compared to a matched control group, performance of the CHI subjects on all measures of the Auditory Verbal Learning Test (AVLT) was significantly worse. Discriminant function analysis correctly classified 90% of subjects as CHI or control using the three most reliable measures of the AVLT. Retention of the learning list following the distractor trial varied with severity of injury as indexed by duration of post-traumatic amnesia (PTA). The more severe the injury (longer PTA), the fewer words were recalled after interference (r = -0.72). Susceptibility of verbal memory to retroactive interference is sensitive to the presence and severity of CHI.

Measuring post-traumatic amnesia (PTA): an historical review.

The duration of post-traumatic amnesia (PTA), which is the period following brain injury when patients are disoriented and impaired in the acquisition of new information, has been used as a behavioural indicator of the severity of injury. This paper reviews earlier retrospective and more recently developed prospective methods of assessing the duration of PTA. Prospective assessment that commences before the resolution of PTA overcomes the possible over- or underestimation of the duration of PTA inherent in methods that assess PTA retrospectively by clinical interview.

Stages of recovery during post-traumatic amnesia and subsequent everyday memory deficits.

Post-traumatic amnesia (PTA) is the period following brain trauma when patients are unable to acquire and retain information. Nineteen patients with brain injury were assessed for PTA, with a new scale, after they regained consciousness, every 24 h. Patients recovered orientation and their capacity to recognise new information, and finally their ability to recall this information. The longer the duration of PTA, the poorer was performance on an everyday memory test given one month after recovery from PTA. Patients with orthopaedic injuries and without brain injury showed minimal impairment on the PTA scale. The predictive value of the scale (multiple R = 0.88) with respect to subsequent everyday memory performance indicates its usefulness as an index of severity of brain injury.

Diversity and sources of rapidly growing mycobacteria associated with infections following cardiac surgery.

Eighty-nine isolates of rapidly growing mycobacteria associated with cardiac bypass-related infections were characterized. Isolates from sporadic infections belonged to eight taxonomic groups and displayed numerous multilocus enzyme genotypes, plasmid profiles, and heavy metal and antibiotic resistance patterns. Compared with 449 noncardiac wound isolates, 45 sporadic cardiac isolates were more likely to be Mycobacterium fortuitum and M. smegmatis and less likely to be M. chelonae. About 80% of cardiac and noncardiac isolates were from southern coastal states. Eight outbreaks of cardiac bypass-related infections were identified. Strains from each outbreak were genotypically distinctive, and five outbreaks involved more than one strain. In two outbreaks, isolates from environmental sources and noncardiac infections were similar or identical to isolates from sternal wound infections. The heterogeneity of these isolates suggests that most isolates are unrelated and are derived from local environmental sources rather than from contaminated commercial surgical materials or devices.

Ampicillin, tetracycline, and chloramphenicol resistant Haemophilus influenzae in adults with chronic lung disease. Relationship of resistance to prior antimicrobial therapy.

Antibiotic resistance in 1,003 sputum isolates of Haemophilus influenzae from adults with chronic lung disease was assessed from January 1983 through June 1986. The incidence of resistance was 3.2% for tetracycline, 0.6% for chloramphenicol, and 12.5% for ampicillin. Resistance to ampicillin or tetracycline usually occurred alone, while 100% of chloramphenicol resistant isolates were co-resistant to tetracycline or ampicillin. More than 90% of antibiotic resistant isolates were nontypable and belonged to biotypes II, III, or V. Chart reviews of 331 patients revealed that patients with ampicillin resistant isolates were more likely than control subjects to have received ampicillin in the prior 6 wk (33% versus 6%, p less than 0.0001), whereas patients with isolates resistant to tetracycline or chloramphenicol plus tetracycline were more likely to have received tetracycline than control subjects (24% and 50%, respectively, versus 5%, p less than 0.005). The incidence of ampicillin resistance and the reluctance of physicians caring for adults to use chloramphenicol suggests that a newer cephalosporin such as cefotaxime may be the initial therapy of choice for severe H. influenzae disease in our patient population.

Characterization of beta-lactamases in Mycobacterium fortuitum including a role in beta-lactam resistance and evidence of partial inducibility.

The beta-lactamases from the 3 biovariants of M. fortuitum were compared on the basis of substrate profiles, susceptibility to enzyme inhibitors, and inducibility in the presence of selected beta-lactams. Despite differences in the distribution of beta-lactamase bands observed when enzymes from different isolates were subjected to isoelectric focusing, substrate profiles for the 3 biovariants were similar. All demonstrated a comparable broad spectrum hydrolytic activity for both cephalosporins and penicillins. The MIC for amoxicillin were reduced 4- to 16-fold when combined with the beta-lactamase inhibitor clavulanic acid, but not to a clinically susceptible range. The degree of reduction in MIC for amoxicillin correlated well with the susceptibility of enzyme to inhibition by clavulanic acid as determined in an in vitro assay. Although all M. fortuitum strains produce beta-lactamase under routine growth conditions, 90% of strains demonstrated an increase in the amount of this enzyme when cultured in the presence of selected beta-lactams as potential inducers. Quantitative assays and isoelectric focusing further indicated that this apparent induction of beta-lactamase is a simple enhancement of the same enzyme(s) produced in the absence of a known inducer. This is the first demonstration of any inducibility among mycobacterial beta-lactamases and suggests that synthesis of these enzymes in M. fortuitum is under some form of regulatory control. These results indicate that the beta-lactamases have a role in resistance of M. fortuitum to the beta-lactams. Other factors, such as permeability and penicillin-binding proteins, were not evaluated.

Susceptibilities of Mycobacterium fortuitum biovariant fortuitum and the unnamed third biovariant complex to heavy-metal salts.

Fifty-three clinical isolates of Mycobacterium fortuitum were tested for susceptibility to heavy-metal salts and antimicrobial agents. The isolates exhibited a bimodal distribution for several heavy metals including mercury, whose resistance is often plasmid mediated. There was a biovariant difference in the incidence of resistance, and resistance to several metal ions was often observed together. There was no apparent relationship between resistance to heavy-metal salts and resistance to antimicrobial agents such as tetracycline.