Do Individual Differences and Aging Effects in the Estimation of Geographical Slant Reflect Cognitive or Perceptual Effects?

Several individual differences including age have been suggested to affect the perception of slant. A cross-sectional study of outdoor hill estimation (N = 106) was analyzed using individual difference measures of age, experiential knowledge, fitness, personality traits, and sex. Of particular note, it was found that for participants who reported any experiential knowledge about slant, estimates decreased (i.e., became more accurate) as conscientiousness increased, suggesting that more conscientious individuals were more deliberate about taking their experiential knowledge (rather than perception) into account. Effects of fitness were limited to those without experiential knowledge, suggesting that they, too, may be cognitive rather than perceptual. The observed effects of age, which tended to produce lower, more accurate estimates of hill slant, provide more evidence that older adults do not see hills as steeper. The main effect of age was to lower slant estimates; such effects may be due to implicit experiential knowledge acquired over a lifetime. The results indicate the impact of cognitive, rather than perceptual factors on individual differences in slant estimation.

A critical look at the evidence for and against elective epinephrine use in the finger.

BACKGROUND: Medical texts continue to perpetuate the belief that epinephrine should not be injected in fingers. Little attention has been paid to analyze the evidence that created this belief to see whether it is valid. The significance is that elective epinephrine finger injection has been shown to remove the need for a tourniquet, and therefore delete sedation and general anesthesia for much of hand surgery. METHODS: All of the evidence for the antiadrenaline dogma comes from 21 mostly pre-1950 case reports of finger ischemia associated with procaine and cocaine injection with epinephrine. The authors performed an in-depth analysis of those 21 cases to determine their validity as evidence. They also examined in detail all of the other evidence in the literature surrounding issues of safety with procaine, lidocaine, and epinephrine injection in the finger. RESULTS: The adrenaline digital infarction cases that created the dogma are invalid evidence because they were also injected with either procaine or cocaine, which were both known to cause digital infarction on their own at that time, and none of the 21 adrenaline infarction cases had an attempt at phentolamine rescue. CONCLUSIONS: The evidence that created the dogma that adrenaline should not be injected into the fingers is clearly not valid. However, there is considerable valid evidence in the literature that supports the tenet that properly used adrenaline in the fingers is safe, and that it removes the need for a tourniquet and therefore removes the need for sedation and general anesthesia for many hand operations.

Randomized double-blind comparison of duration of anesthesia among three commonly used agents in digital nerve block.

BACKGROUND: Three local anesthetics are commonly used for digital nerve block: 2% lidocaine with 1:100,000 epinephrine, 2% lidocaine, and 0.5% bupivacaine. The authors have not identified a study that has compared these three agents in digital nerve block in a randomized fashion. The goal of this study was to determine which of the three agents provided the longest duration of digital nerve blockade. METHODS: Thirty volunteers had the long finger of each hand along with one of their small fingers anesthetized with one of the above agents, respectively. The local anesthetic agent to be used in each finger was randomized. A double-blind design was used. Volunteers reported the time that each of their fingers returned to normal sensation at the tip. An analysis of variance was used to detect significant differences among the three groups, and subsequent pair-wise comparisons were performed using post hoc Tukey tests. RESULTS: The mean duration of anesthesia was as follows: 0.5% bupivacaine, 24.9 hours; 2% lidocaine with epinephrine (1:100,000), 10.4 hours; and 2% lidocaine, 4.9 hours. In both the Bonferroni and Tukey tests, all three agents provided significantly different durations of digital nerve blockade (p = 0.01). CONCLUSIONS: At an average of 24.9 hours, bupivacaine (0.5%) provides a significantly longer digital anesthesia time than the average 10.4 hours achieved by 2% lidocaine with epinephrine (1:100,000), which in turn provides twice as long an anesthesia time as 2% lidocaine (average, 4.9 hours).

Antibacterial research and development in the 21(st) Century--an industry perspective of the challenges.

The continued evolution of resistance to antibiotics has led to wide ranging consultation at National and International levels as to how to address this issue. In addition to attempting to limit the spread of resistance there is growing consensus that a cornerstone requirement is the development of new antibiotics to help redress the balance of resistance versus available antibiotics. The availability of new technologies such as genomics has opened up new approaches for antibacterial research. It would appear that from an industry perspective, the research and development of antibiotics should be an attractive option. However, this is not the current perception at the majority of large pharmaceutical companies. In addition, the perceived failure of new technologies to create another golden age of new antibacterial classes has led many companies to prioritise other areas of research and, in some cases, to exit antibacterial research. In response, a plethora of small biotech companies have emerged with an interest in antibacterial discovery and large pharmaceutical companies may look to these as a source of development candidates although, to date, these have contributed a very low number of truly novel antibiotic lead compounds. As a reaction to these changes several initiatives are ongoing to examine ways to incentivise antibacterial research and development and ensure a healthy pipeline of compounds in the 21st Century.

Treatment of electrical burns by single debridement followed by free-flap coverage: How important is timing?

BACKGROUND: High-voltage electrical burns involving the extremities may cause marked loss of skin and subcutaneous tissue exposing underlying bone and tendon. Treatment of electrical burns has historically involved serial debridement with late wound closure. Success has been reported with the use of microvascular free-flap transfer within three days of injury. OBJECTIVE: Seven patients with severe high-voltage electrical burns are presented. The application and timing of microvascular free-flap coverage is discussed. RESULTS: Six of the seven patients achieved successful healing with the free flaps. CONCLUSION: Delay of microvascular free-flap coverage beyond the previously published three-day protocol may not dramatically affect treatment success.

HISTORIQUE: Des brûlures électriques de haute tension touchant les extrémités peuvent provoquer une perte marquée des tissus cutanés et sous-cutanés qui exposent l'os et le tendon sous-jacents. D'ordinaire, le traitement des brûlures électriques entraîne un débridement sériel et une fermeture tardive de la plaie. Le transfert microvasculaire d'un lambeau libre dans les trois jours suivant la brûlure peut assurer le succès. OBJECTIF: Sept patients présentant des brûlures électrique de haute tension sont présentés. L'application et le moment de la couverture par lambeau libre sont exposés. RÉSULTATS: Les lambeaux libres ont guéri chez six des sept patients. CONCLUSION: Le retard de la couverture microvasculaire par lambeau libre après le protocole limité à trois jours préconisé auparavant ne nuirait pas énormément au succès du traitement.

The art of fusion: from penams and cephems to penems.

This synopsis of published literature summarises the key chemical and bacteriological characteristics of penicillins, i.e. penams, cephalosporins, i.e. cephems, and their hybrid structure, i.e. the penems. Consequently, the antibacterial spectrum of a typical penem, e.g. faropenem, encompasses gram-positive as well as gram-negative species. Dependent from the substituents at position 1 of the five-membered saturated ring fused to the beta-lactam ring oxa-, carba-, or thiopenems can be differentiated. A major determinant of their antibacterial activity and CNS-excitatory potential, however, is the C-2 side chain. The excitatory potential correlates with the basicity of the C-2 side chain as does their antibacterial activity against gram-negative species and non-fermenters like P. aeruginosa. Lipophilicity is a determinant for good in vitro activity against gram-positive bacteria. Several investigational penems exhibit interesting antibacterial spectra, encompassing methicillin resistant staphylococci, enterococci and even P. aeruginosa due to their improved binding affinity to both wild-type and modified low-affinity penicillin binding proteins. The development of these agents may offer therapeutic alternatives for the management of infections.

Antibiotic susceptibilities of Haemophilus influenzae in central Scotland.

OBJECTIVE: To ascertain the incidence of antibiotic resistance in Haemophilus influenzae in central Scotland and the beta-lactamases produced by these isolates. METHODS: A total of 213 H. influenzae isolates from four medical centers in Scotland [Aberdeen (n=58), Edinburgh (n=55), Glasgow (n=64) and Dundee (n=36)] were tested for susceptibility to a range of antimicrobials including beta-lactams, beta-lactam/beta-lactamase-inhibitor combinations, and a representative 4-quinolone, antifolate and macrolide. Susceptibility testing of the beta-lactam/beta-lactamase-inhibitor combination amoxicillin plus clavulanic acid was conducted at both 2:1 and 4:1 ratios and with clavulanic acid fixed at a concentration of 2 mg/L. Each strain was further investigated for the presence of beta-lactamase activity. RESULTS: Although the incidence of resistance to amoxicillin was 15%, in the presence of clavulanic acid, this resistance was reduced to 4.2%, 5.6% and 4.2% with the 2:1 ratio, 4:1 ratio and 2 mg/L fixed concentration, respectively. Sixteen percent of the isolates demonstrated immediate beta-lactamase production. Isoelectric focusing showed that 77.4%, 16.1% and 6.5% of the beta-lactamase-positive strains were found to contain TEM-1, VAT-1 and both TEM-1 and VAT-1 beta-lactamases, respectively. A further 29% of the strains were recognized as being beta-lactamase-positive after prolonged incubation with nitrocephin. CONCLUSIONS: This study suggests that current testing for beta-lactamases may underestimate the prevalence of beta-lactamase production in H. influenzae.