Triggered high-purity telecom-wavelength single-photon generation from p-shell-driven InGaAs/GaAs quantum dot.

We report on the experimental demonstration of triggered single-photon emission at the telecom O-band from In(Ga)As/GaAs quantum dots (QDs) grown by metal-organic vapor-phase epitaxy. Micro-photoluminescence excitation experiments allowed us to identify the p-shell excitonic states in agreement with high excitation photoluminescence on the ensemble of QDs. Hereby we drive an O-band-emitting GaAs-based QD into the p-shell states to get a triggered single photon source of high purity. Applying pulsed p-shell resonant excitation results in strong suppression of multiphoton events evidenced by the as measured value of the second-order correlation function at zero delay of 0.03 (and ~0.005 after background correction).

A bright triggered twin-photon source in the solid state.

A non-classical light source emitting pairs of identical photons represents a versatile resource of interdisciplinary importance with applications in quantum optics and quantum biology. To date, photon twins have mostly been generated using parametric downconversion sources, relying on Poissonian number distributions, or atoms, exhibiting low emission rates. Here we propose and experimentally demonstrate the efficient, triggered generation of photon twins using the energy-degenerate biexciton-exciton radiative cascade of a single semiconductor quantum dot. Deterministically integrated within a microlens, this nanostructure emits highly correlated photon pairs, degenerate in energy and polarization, at a rate of up to (234±4) kHz. Furthermore, we verify a significant degree of photon indistinguishability and directly observe twin-photon emission by employing photon-number-resolving detectors, which enables the reconstruction of the emitted photon number distribution. Our work represents an important step towards the realization of efficient sources of twin-photon states on a fully scalable technology platform.

Exploring Dephasing of a Solid-State Quantum Emitter via Time- and Temperature-Dependent Hong-Ou-Mandel Experiments.

We probe the indistinguishability of photons emitted by a semiconductor quantum dot (QD) via time- and temperature-dependent two-photon interference (TPI) experiments. An increase in temporal separation between consecutive photon emission events reveals a decrease in TPI visibility on a nanosecond time scale, theoretically described by a non-Markovian noise process in agreement with fluctuating charge traps in the QD's vicinity. Phonon-induced pure dephasing results in a decrease in TPI visibility from (96±4)% at 10 K to a vanishing visibility at 40 K. In contrast to Michelson-type measurements, our experiments provide direct access to the time-dependent coherence of a quantum emitter on a nanosecond time scale.

Highly indistinguishable photons from deterministic quantum-dot microlenses utilizing three-dimensional in situ electron-beam lithography.

The success of advanced quantum communication relies crucially on non-classical light sources emitting single indistinguishable photons at high flux rates and purity. We report on deterministically fabricated microlenses with single quantum dots inside which fulfil these requirements in a flexible and robust quantum device approach. In our concept we combine cathodoluminescence spectroscopy with advanced in situ three-dimensional electron-beam lithography at cryogenic temperatures to pattern monolithic microlenses precisely aligned to pre-selected single quantum dots above a distributed Bragg reflector. We demonstrate that the resulting deterministic quantum-dot microlenses enhance the photon-extraction efficiency to (23±3)%. Furthermore we prove that such microlenses assure close to pure emission of triggered single photons with a high degree of photon indistinguishability up to (80±7)% at saturation. As a unique feature, both single-photon purity and photon indistinguishability are preserved at high excitation power and pulsed excitation, even above saturation of the quantum emitter.

Operating single quantum emitters with a compact Stirling cryocooler.

The development of an easy-to-operate light source emitting single photons has become a major driving force in the emerging field of quantum information technology. Here, we report on the application of a compact and user-friendly Stirling cryocooler in the field of nanophotonics. The Stirling cryocooler is used to operate a single quantum emitter constituted of a semiconductor quantum dot (QD) at a base temperature below 30 K. Proper vibration decoupling of the cryocooler and its surrounding enables free-space micro-photoluminescence spectroscopy to identify and analyze different charge-carrier states within a single quantum dot. As an exemplary application in quantum optics, we perform a Hanbury-Brown and Twiss experiment demonstrating a strong suppression of multi-photon emission events with g((2))(0) < 0.04 from this Stirling-cooled single quantum emitter under continuous wave excitation. Comparative experiments performed on the same quantum dot in a liquid helium (LHe)-flow cryostat show almost identical values of g((2))(0) for both configurations at a given temperature. The results of this proof of principle experiment demonstrate that low-vibration Stirling cryocoolers that have so far been considered exotic to the field of nanophotonics are an attractive alternative to expensive closed-cycle cryostats or LHe-flow cryostats, which could pave the way for the development of high-quality table-top non-classical light sources.

Which goal for fluid therapy during colorectal surgery is followed by the best outcome: near-maximal stroke volume or zero fluid balance?

BACKGROUND: We aimed to investigate whether fluid therapy with a goal of near-maximal stroke volume (SV) guided by oesophageal Doppler (ED) monitoring result in a better outcome than that with a goal of maintaining bodyweight (BW) and zero fluid balance in patients undergoing colorectal surgery. METHODS: In a double-blinded clinical multicentre trial, 150 patients undergoing elective colorectal surgery were randomized to receive fluid therapy after either the goal of near-maximal SV guided by ED (Doppler, D group) or the goal of zero balance and normal BW (Zero balance, Z group). Stratification for laparoscopic and open surgery was performed. The postoperative fluid therapy was similar in the two groups. The primary endpoint was postoperative complications defined and divided into subgroups by protocol. Analysis was performed by intention-to-treat. The follow-up was 30 days. The trial had 85% power to show a difference between the groups. RESULTS: The number of patients undergoing laparoscopic or open surgery and the patient characteristics were similar between the groups. No significant differences between the groups were found for overall, major, minor, cardiopulmonary, or tissue-healing complications (P-values: 0.79; 0.62; 0.97; 0.48; and 0.48, respectively). One patient died in each group. No significant difference was found for the length of hospital stay [median (range) Z: 5.00 (1-61) vs D: 5.00 (2-41); P=0.206]. CONCLUSIONS: Goal-directed fluid therapy to near-maximal SV guided by ED adds no extra value to the fluid therapy using zero balance and normal BW in patients undergoing elective colorectal surgery.

Short hospital stay and low complication rate are possible with a fully implemented fast-track model after elective colonic surgery.

PURPOSE: The aim was to implement a fast-track model in a colorectal unit. We evaluated its effects on hospital stay and complication rate after elective open colonic surgery. METHODS: A fast-track programme was fully implemented, with a dedicated staff and a schedule for all perioperative procedures which included provision of information to patients, surgical guidelines, mobilisation and postoperative care. All previously existing procedures were modified according to previously published guidelines. Criteria for success with regard to the length of hospital stay and rates and types of complications were defined. Fast-tracked patients were compared with patients not included in the programmes that were operated during the same period. RESULTS: 131 fast-tracked patients were compared with 39 control patients. The fast track significantly reduced the median hospital stay from 7 to 3 days (p < 0.0001). There was no difference in complication rates between the two groups, and no major complications were observed after early discharge from the hospital. The readmission rate was 15% in the fast-track group and 16% with the control patients. CONCLUSION: Implementation of a fast track after open elective colonic surgery is safe and reduces the length of hospital stay.

Size-dependent fine-structure splitting in self-organized InAs/GaAs quantum dots.

A systematic variation of the exciton fine-structure splitting with quantum dot size in single quantum dots grown by metal-organic chemical vapor deposition is observed. The splitting increases from to as much as with quantum dot size. A change of sign is reported for small quantum dots. Model calculations within the framework of eight-band theory and the configuration interaction method were performed. Different sources for the fine-structure splitting are discussed, and piezoelectricity is pinpointed as the only effect reproducing the observed trend.

Primary hyperparathyroidism: intraoperative PTH-measurements.

BACKGROUND: With the development of rapid assays and intraoperative measurement of intact parathyroid hormone (PTH), new strategies in the handling of patients with primary hyperparathyroidism (pHPT) have evolved. AIM: The aim of our study was to illustrate the performance of the intraoperative PTH measurement as a predictor of successful cure. MATERIAL AND METHODS: From September 1999 to April 2002 143 patients with pHPT underwent a parathyroid operation (bilateral neck exploration with identification of all parathyroid glands) with intraoperative measurements of plasma PTH (immediately prior to surgery (T0) and 5 minutes after gland excision (T5)). A positive test result was defined as plasma PTH values at T5 below 20% of T0 or a value in the normal range below 7.6 pmol/l. Hence T5 values above 20% of T0 and above 7.6 pmol/l were considered test negative. RESULTS: 122 patients (85%) were test positive and cured, 11 patients (8%) were test negative but cured, and 10 patients (7%) were test negative and not cured by the primary operation. Consequently, the sensitivity of the test was 0.92 and the specificity 1.00. CONCLUSIONS: The rapid PTH test used is a reliable predictor of a successful outcome in pHPT patients undergoing parathyroid surgery.

Epidural anaesthesia with bupivacaine does not cause increased oedema in small gut anatomoses in pigs.

BACKGROUND AND OBJECTIVE: Epidural analgesia is widely used for abdominal surgery due to the properties of 'stress-free' anaesthesia and superior pain control. Nevertheless, sympathomimetics are known to antagonize inflammation. The present study was performed to investigate if epidural local anaesthetics caused increased local oedema formation. METHODS: Thirty Dansk Landrace pigs were randomized into three groups: epidural bupivacaine, epidural morphine or intravenous (i.v.) fentanyl. All animals were anaesthetized with isoflurane and i.v. midazolam and received an identical fluid regimen. Six small bowel resections were performed over a 3-h period and during the following 3 h the anastomoses were resected. Primary end-points were water content in small bowel and mesentery samples before and after gut anastomosis, lymph flow and urine production. RESULTS: The water content in the small bowel samples was not changed by surgery or by the different anaesthetic protocols. In the mesenteric tissue, there was a highly significant increase in water content of the postanastomotic samples compared to pre-anastomotic samples (P < 0.001) and a significant time treatment interaction was revealed (P < 0.05) suggesting an increase in oedema formation in the epidural local anaesthetic group. Lymph flow did not change during the experiments and there were no significant differences between the groups (P = 0.80). The mean total urine output was 44% higher in the epidural morphine group compared to the local anaesthetic group (P = 0.17). CONCLUSIONS: Surgery did not increase gut wall water content, but acute oedema formation resulted in the peri-resectional mesenterial tissue, more prominently so in the bupivacaine group.

Effects of preoperative oral carbohydrates and peptides on postoperative endocrine response, mobilization, nutrition and muscle function in abdominal surgery.

BACKGROUND: Surgery is succeeded by long-lasting state of relative peripheral insulin resistance, which is reduced by giving glucose infusion or oral carbohydrate-rich drinks immediate before operating instead of fasting. The aim of the present study was to investigate whether oral carbohydrate or carbohydrate with peptide drinks preoperatively instead of fasting would improve postoperative voluntary muscle strength, nutritional intake and ambulation, decrease postoperative fatigue, anxiety and discomfort, and reduce the endocrine response to surgery. METHODS: Forty-eight patients were included and randomized into three groups to receive 2 x 400 ml of carbohydrate-rich drinks or to fast overnight and allowed only water. Voluntary grip and quadriceps strength, body composition, pulmonary function, VAS-score of eight parameters of wellbeing, muscle biopsies and insulin, glucagon, IGF-1 and free fatty acids were measured before and after the operation. The basic postoperative regimen for all groups were immediate oral nutrition and early enforced mobilization. RESULTS: Significant postoperative decrease in glycogen synthase activity in the muscle biopsies was reduced in the intervention groups, and in combination, the intervention groups had a less reduced quadriceps strength after one week (-10% vs. -16%, NS) and one month (-5% vs. -13%, P < 0.05). Minor changes in the endocrine response to surgery were found without differences between the groups, and there were no differences between the groups in ambulation time, nutritional intake or subjective measures of wellbeing.

The incidence of transient neurologic symptoms (TNS) after spinal anaesthesia in patients undergoing surgery in the supine position. Hyperbaric lidocaine 5% versus hyperbaric bupivacaine 0.5%.

BACKGROUND: The incidence of TNS after spinal anaesthesia is a problem. Especially the use of hyperbaric lidocaine in patients placed in the lithotomy position during surgery has been associated with a high incidence of TNS. The present study was performed to investigate whether TNS is present more frequently in patients undergoing surgery in the supine position with use of hyperbaric lidocaine compared with hyperbaric bupivacaine. METHOD: Seventy patients were included and randomised to receive either hyperbaric lidocaine or hyperbaric bupivacaine. All patients were contacted on the first and third postoperative days by an anaesthesiologist blinded to the local anaesthetic used. The patients were asked about symptoms of TNS, pain not associated with the operation area, and asked to grade the complaints after a verbal analogue score from 0 to 10. RESULTS: We found a total of ten patients who showed signs of TNS. There were nine patients in the lidocaine group (26%) who showed signs of TNS compared to only one patient in the bupivacaine group (3%) (P<0.01). The average score of TNS complaints was 3.5. A total of 13 patients (19%) complained of back pain. There were no significant differences with regard to which local anaesthetic was used. The average score of back pain was 3.3. CONCLUSION: TNS is a significant problem in patients having spinal anaesthesia with hyperbaric lidocaine compared to hyperbaric bupivacaine, both in the supine position. For day-case surgery, TNS would start after dismissal from hospital. The use of hyperbaric lidocaine is therefore questionable, even though these problems are of an order that the majority of patients would still choose spinal anaesthesia for future operations.

[Fiber optic tracheoscopy in percutaneous dilation tracheostomy]. / Fiberoptisk trakeoskopi ved perkutan dilatationstrakeostomi.

Percutaneous dilatational tracheostomy (PDT) was performed on a 64 year-old female multitraumatised patient. Because of difficulties during the procedure, fiberoptic tracheoscopy was carried out and revealed perforation and dilatation of the endotracheal tube. The error was corrected with little loss of time, and no complications were observed after finishing the procedure. We recommend the use of routine fiberoptic tracheoscopy during and after percutaneous dilatational tracheostomy as suggested by Ciaglia et al (2).

alpha-Trinositol prevents increased negativity of interstitial fluid pressure in rat skin and trachea induced by dextran anaphylaxis.

The new anti-inflammatory agent alpha-trinositol (D-myo-inositol-1,2,6-trisphosphate), is suggested to act on the cellular adhesion receptor towards extracellular matrix components, the beta1-integrins, and may therefore represent a novel principle for therapy of the phenomena associated with acute inflammation. Increased negativity of interstitial fluid pressure (p(if)) is a major driving force for the rapid edema formation in trachea and skin associated with dextran anaphylaxis in the rat. We therefore used this experimental model to study the effect of alpha-trinositol in skin and trachea of pentobarbital anesthetized rats. p(if) was measured with sharpened glass capillaries (3-7 microm) connected to a servocontrolled counterpressure system. alpha-Trinositol (10 mg) was given before or after dextran. Circulatory arrest was induced 2 min after i.v. dextran to limit the increased capillary fluid filtration associated with the anaphylactic reaction. This increased filtration will otherwise raise interstitial volume and thereby p(if) and cause an underestimation of a potential increased negativity of p(if). In the trachea, p(if) was 0.0 +/- 1.0 mmHg (S.D.) and -1.4 +/- 0.5 mmHg in controls given saline vehicle and alpha-trinositol (P > 0.05), respectively, and fell to -8.5 +/- 2.7 mmHg after dextran (P < 0.01). alpha-Trinositol given 2 min prior to or after dextran resulted in p(if) of -1.7 +/- 1.2 mmHg (P > 0.05 versus control, P < 0.01 versus dextran) and -4.7 +/- 3.0 mmHg (P < 0.01 versus control and dextran), respectively. In skin, i.v. dextran caused p(if) to fall from -0.6 +/- 0.5 to -4.6 +/- 1.9 mmHg (P < 0.001). When alpha-trinositol was given prior to dextran the corresponding figures were -0.4 +/- 0.8 and -0.9 +/- 1.1 mmHg, respectively (P > 0.05). Subdermal administration of alpha-trinositol after i.v. dextran and circulatory arrest normalized p(if) in concentration of 100, 10 and partly at 1 mg/ml. Thus, alpha-trinositol prevented the increased negativity of p(if) induced by dextran anaphylaxis when administered prior to as well as after dextran showing that the alpha-trinositol also could influence an already started inflammatory reaction.

A novel physiological function for platelet-derived growth factor-BB in rat dermis.

1. The present experiments describe a role for platelet-derived growth factor-BB and cellular adhesion receptors towards extracellular matrix molecules (beta 1-integrins) in control of interstitial fluid pressure (Pif). 2. Pif was measured in rat skin with sharpened glass capillaries (3-7 microns) connected to a servocontrolled counter-pressure system. 3. The collagen and laminin-binding alpha 2 beta 1-integrin is involved in the control of Pif since subdermal injection (5 microliters) of monoclonal hamster anti-rat alpha 2 beta 1-integrin IgG (anti-alpha 2 beta 1) resulted in increased negativity of Pif. Control Pif averaged -0.88 +/- 0.23 mmHg (+/- S.D.) and decreased to -2.50 +/- 0.35 mmHg (P < 0.05) and -3.88 +/- 1.45 mmHg (P < 0.05) at anti-alpha 2 beta 1 concentrations of 0.56 and 1.12 mg ml-1, respectively. 4. The effect of anti-alpha 2 beta 1 was abolished when platelet-derived growth factor-BB (PDGF-BB) (200 ng ml-1) was injected together with anti-alpha 2 beta 1. 5. The time- and dose-responses of PDGF-BB to counteract increased negativity of Pif were studied further using dextran anaphylaxis as an experimental model inducing increased negativity of Pif in skin. Control Pif averaged -0.33 +/- 0.43 mmHg and fell to -4.10 +/- 1.47 mmHg within 10 min after dextran (P < 0.01). Subsequent subdermal injection of PDGF-BB at 200 ng ml-1 normalized Pif in 10-20 min which became -1.37 +/- 1.23 mmHg (P < 0.01 versus dextran, P > 0.05 versus control). PDGF-BB had little or no effect at 50 ng ml-1. PDGF-AA and basic fibroblast growth factor had no effect on Pif. 6. The in vivo function reported for PDGF-BB has not been described previously and provides further evidence for active participation of connective tissue cells in control of Pif by altering tension on extracellular matrix structures.

Is the pencil point spinal needle a better choice in younger patients? A comparison of 24G Sprotte with 27G Quincke needles in an unselected group of general surgical patients below 46 years of age.

Reports have indicated that there are less postoperative complaints after the use of pencil pointed spinal needles. We compared a 24G Sprotte needle with a 27G Quincke needle in a randomised study of 200 healthy patients (49% females), aged 15-46 years. Four patients (2%) reported postdural puncture headache, three with the 24G Sprotte needle and one with the 27G Quincke needle. Thirteen patients (7%) suffered with nonspecific headache, with no significant difference between the two groups. Of the 57 (29%) who reported backpain, a significantly higher proportion had received spinal anaesthesia with the Sprotte needle (OR = 2.06). There was a significantly higher incidence of insufficient blocks after dural puncture with the Sprotte needle. Ease of needle insertion and number of puncture attempts was the same for both needle types.

The anti-inflammatory agent alpha-trinositol exerts its edema-preventing effects through modulation of beta 1 integrin function.

Edema formation in acute inflammation can be induced through lowering of interstitial fluid pressure (Pif) and seems to involve dynamic beta 1 integrin-mediated interactions between dermal cells and extracellular matrix fibers. The present experiments investigate the role of beta 1 integrins in the control of Pif. The anti-inflammatory drug alpha-trinositol (1,2,6-D-myo-inositol trisphosphate) stabilizes Pif in acute inflammation. Pretreatment with 5 mg IV alpha-trinositol in pentobarbital-anesthetized rats inhibited the lowering in Pif and the edema formation induced by subdermal injection of anti-beta 1 integrin IgG. This stabilization of the beta 1 integrin function in vivo was paralleled by effects of alpha-trinositol on contraction of fibroblast-populated three-dimensional collagen lattices in vitro. alpha-Trinositol was additive to the known stimulatory effect of platelet-derived growth factor-BB on the final gel size in the collagen gel contraction assay. Furthermore, alpha-trinositol counteracted the inhibitory effect of anti-beta 1 integrin Fab fragments on collagen gel contraction. Finally, subdermal injection of dibutyryl-cAMP (db-cAMP) induced increased negativity of Pif to the same extent as did anti-beta 1 integrin antibodies, and in vitro db-cAMP reduced the ability of fibroblasts to contract collagen gels. The latter effect was opposed by alpha-trinositol. The data demonstrate that alpha-trinositol modulates beta 1 integrin function and may do so via intracellular pathways in turn affecting the function and/or cell surface expression of beta 1 integrins and suggest that alpha-trinositol can serve as a tool to study integrin function. Furthermore, the data indicate that the collagen contraction assays may provide important information of the control of Pif in vivo.

Increased hyaluronan flux in canine paw lymph is induced by histamine and the histamine-releasing agent compound 48/80.

The present experiments investigated hyaluronan (HYA) flux from skin of pentobarbital anesthetized mongrel dogs when transcapillary fluid flux was increased by local intraarterial injection of histamine (50 micrograms) or Compound 48/80 (C48/80) (100 micrograms) inducing mast cell degranulation. A prenodal lymphatic draining the hindpaw was cannulated and the paw flexed passively at 50 times/min. Grand mean (n = 18) of control lymph flow and HYA concentration was 16 +/- (SD) 14 microliters/min and 8.8 +/- 2.3 micrograms/ml, respectively. Lymph flow increased 11- and 15-fold within 10 min after histamine and C48/80 injection, respectively, and returned to control values after 3 h for histamine while it did not return fully in the C48/80 group. HYA concentration decreased by 30 and 40% during the first hour after histamine and C48/80, respectively, while HYA flux increased 11-15 times control. Control experiments (saline vehicle) showed an unexpected and gradual increase in HYA concentration during the 8-hour experimental period, regardless of unchanged lymph flow. This increase became statistically significant at the end of the experimental period, suggesting either an increased synthesis or increased rate of release of bound HYA from the paw. The present data show that HYA is loosely bound and easily mobilized from the interstitial matrix and that histamine and C48/80 cause a release of bound HYA from the interstitium. An increase in HYA concentration towards the end of the 8-hour experimental period most likely represents an increased synthesis of HYA.

Intrathecal anaesthesia in patients under 45 years: incidence of postdural puncture symptoms after spinal anaesthesia with 27G needles.

Postoperative headache and backpain has limited the use of intrathecal anaesthesia in younger patients (15-45 years). We studied postoperative complaints among 133 healthy young patients (mean age 30.0 years, 47% females) who received spinal anaesthesia with a 27G needle. Postoperatively, 5 patients (4%) complained of postdural puncture headache (PDPH), 18 (14%) reported nonspecific headache, while 27 (20%) suffered from backpain. PDPH was not related to sex, age, day-care surgery, number of puncture attempts, or obstetric procedures. Backpain was significantly more common among females, and among in-patients. One hundred and sixteen patients (87%) would accept spinal anaesthesia if they were to undergo the same surgical procedure again. Compared to other studies, we find the incidence of postanaesthetic complaints to be acceptable, also among day-care patients. The PDPH seemed to be lightly incapacitating, and only one patient required blood patching.

Interstitial fluid pressure in rat skin becomes more negative in the initial phase of carrageenan-induced edema.

Increased negativity of the interstitial fluid pressure (P(i)) in the skin is a major driving force to create the initial edema in burn injury and, to a smaller degree, in the edemas formed in the initial phase of the chemical irritation induced by xylene and the anaphylactic reaction induced by dextran. The phenomenon of increased negativity of P(i) is the basis for stating that the connective tissues become 'active' in fluid exchange since the increased negativity of P(i) will be a major driving pressure for transcapillary fluid flux under these circumstances. The present study was performed to investigate if increased negativity of P(i) contributes to formation of the inflammatory edema induced by carrageenan in the rat paw skin, since carrageenan inflammation involves mechanisms principally different from burn injury, xylene and dextran anaphylaxis. Control P(i) averaged -0.42 mmHg +/- 0.12 (SE). Injection of normal saline increased P(i) by 1.4 mmHg in 6-10 min. In animals with intact circulation P(i) decreased to -4.75 +/- 0.60 mmHg in the same time period following subdermal injection of carrageenan and later returned to control values by 21-30 min. To prevent the edema formation which will increase P(i) and potentially lead to underestimation of an increased negativity in P(i), measurements were also performed after circulatory arrest when there will be no transcapillary fluid flux in response to the inflammatory agent. In this group P(i) fell to -4.10 +/- 0.71 mmHg (11-20 min) and remained at -2.75 to -4.10 mmHg throughout the observation period. Premedication with aprotinin (protease inhibitor), indomethacin (prostaglandin inhibitor) and 1,2 benzopyrone did not change the increased negativity in P(i) induced by carrageenan. In conclusion, the increased negativity of P(i) contributes to the formation of edema also in carrageenan-induced inflammation and is an effect of carrageenan which has previously not been described.