Systematic review with meta-analysis of the impact of surgical fellowship training on patient outcomes.

BACKGROUND: The number of surgeons entering fellowship training before independent practice is increasing. This may have a negative impact on surgeons in training. The impact of fellowship training on patient outcomes is not yet known. This review aimed to investigate the impact of fellowship training in surgery on patient outcomes. METHODS: A systematic review of the literature was conducted to identify studies exploring the structural and surgeon-specific characteristics of fellowship training on patient outcomes. Data from these studies were extracted, synthesized and reported qualitatively, or quantitatively through meta-analysis. RESULTS: Twenty-three studies were included. The mortality rate for patients in centres with an affiliated fellowship programme was lower than that for centres without (odds ratio 0.86, 95 per cent c.i. 0.84 to 0.88), as was the rate of complications (odds ratio 0.90, 0.78 to 1.02). Surgeons without fellowship training converted more laparoscopic operations to open surgery than those with fellowship training (risk ratio (RR) 1.04, 95 per cent c.i. 1.03 to 1.05). Comparison of outcomes for senior surgeons versus current fellows showed no differences in rates of mortality (RR 1.00, 1.00 to 1.01), complications (RR 1.03, 0.98 to 1.08) or conversion to open surgery (RR 1.01, 1.00 to 1.01). CONCLUSION: Fellowship training appears to have a positive impact on patient outcomes.

Postoperative recurrence of Crohn's disease: impact of endoscopic monitoring and treatment step-up.

AIM: Eighty per cent of patients with Crohn's disease require surgery, of whom 70% will require a further operation. Recurrence occurs at the anastomosis. Although often recommended, the impact of postoperative colonoscopy and treatment adjustment is unknown. METHOD: Patients with a bowel resection over a 10-year period were reviewed and comparison made between those who did and did not have a postoperative colonoscopy within 1 year of surgery, and those who did or did not have a step-up in drug therapy. RESULTS: Of 222 patients operated on, 136 (65 men, mean age 33 years, mean disease duration 8 years, median follow-up 4 years) were studied. Of 70 patients with and 66 without postoperative colonoscopy, clinical recurrence occurred in 49% and 48% (NS) and further surgery in 9% and 5% (NS). Eighty-nine per cent of colonoscoped patients had a decision based on the colonoscopic findings: of these, 24% had a step-up of drug therapy [antibiotics (n =10), aminosalicylates (n=2), thiopurine (n=5), methotrexate (n=1)] and 76% had no step-up in drug therapy. In colonoscoped patients clinical recurrence occurred in 9 (60%) of 15 patients with, and 23 (49%) of 47 without step-up and surgical recurrence in 2 (13%) of 15 and 4 (9%) of 47 (NS). CONCLUSION: Clinical recurrence occurs in a majority of patients soon after surgery. In this cohort, there was no clinical benefit from colonoscopy or increased drug therapy within 1 year after operation. However, the response to the endoscopic findings was not standardized and immunosuppressive therapy was uncommon. Standardizing timing of colonoscopy and drug therapy, including more intense therapy, may improve outcome, although this remains to be proven.

Distinct levels of Sox9 expression mark colon epithelial stem cells that form colonoids in culture.

Sox9 is an high-mobility group box transcription factor that is expressed in the stem cell zone of the small intestine and colon. We have previously used a Sox9EGFP mouse model to demonstrate that discrete levels of Sox9 expression mark small intestine epithelial stem cells that form crypt/villus-like structures in a three-dimensional culture system (Formeister EJ, Sionas AL, Lorance DK, Barkley CL, Lee GH, Magness ST. Am J Physiol Gastrointest Liver Physiol 296: G1108-G1118, 2009; Gracz AD, Ramalingam S, Magness ST. Am J Physiol Gastrointest Liver Physiol 298: G590-G600, 2010). In the present study, we hypothesized that discrete levels of Sox9 expression would also mark colonic epithelial stem cells (CESCs). Using the Sox9EGFP mouse model, we show that lower levels of Sox9 mark cells in the transit-amplifying progenitor cell zone, while higher levels of Sox9 mark cells in the colonic crypt base. Furthermore, we demonstrate that variable SOX9 levels persist in cells of colonic adenomas from mice and humans. Cells expressing lower Sox9 levels demonstrate gene expression profiles consistent with more differentiated populations, and cells expressing higher Sox9 levels are consistent with less differentiated populations. When placed in culture, cells expressing the highest levels of Sox9 formed "colonoids," which are defined as bodies of cultured colonic epithelial cells that possess multiple cryptlike structures and a pseudolumen. Cells expressing the highest levels of Sox9 also demonstrate multipotency and self-renewal in vitro, indicating functional stemness. These data suggest a dose-dependent role for Sox9 in normal CESCs and cells comprising colon tumors. Furthermore, distinct Sox9 levels represent a new biomarker to study CESC and progenitor biology in physiological and disease states.

Faecal diversion in the management of perianal Crohn's disease.

AIM: Severe perianal Crohn's disease remains an uncommon but important indication for faecal diversion (FD). The advent of biological therapy such as infliximab for Crohn's disease is considered to have improved the outcome for these patients. The aim of this study was to assess the outcome of patients undergoing FD for perianal Crohn's disease and the impact of biological therapy (infliximab). METHOD: Retrospective chart review was undertaken of patients who underwent FD for management of perianal Crohn's disease at two tertiary centres between 1990 and 2007. Patient demographics, disease extent and use of biological therapy were recorded. Subsequent surgery was assessed. The impact of infliximab on rates of proctocolectomy and restoration of intestinal continuity was assessed. RESULTS: Twenty-one patients (one male, 20 female), median age 34 years (range 21-67 years), underwent FD for perianal Crohn's disease. At a median follow-up time of 22 months (range 4-121 months), four patients had undergone stoma closure, 11 had had proctocolectomy and six had a stoma in situ. The effects of the procedure on severity of perianal disease were no effect in four (19%), temporary improvement in six (29%), initial improvement with later plateau in seven (33%) and healing in four patients (19%). Eleven patients (52%) received infliximab. In this group, four underwent proctocolectomy and two had intestinal continuity restored. This was not significantly different from the noninfliximab group. CONCLUSION: Patients undergoing FD for perianal Crohn's disease have <20% likelihood of restoration of intestinal continuity. This is not improved with biological therapy.

Implications for prediction and hazard assessment from the 2004 Parkfield earthquake.

Obtaining high-quality measurements close to a large earthquake is not easy: one has to be in the right place at the right time with the right instruments. Such a convergence happened, for the first time, when the 28 September 2004 Parkfield, California, earthquake occurred on the San Andreas fault in the middle of a dense network of instruments designed to record it. The resulting data reveal aspects of the earthquake process never before seen. Here we show what these data, when combined with data from earlier Parkfield earthquakes, tell us about earthquake physics and earthquake prediction. The 2004 Parkfield earthquake, with its lack of obvious precursors, demonstrates that reliable short-term earthquake prediction still is not achievable. To reduce the societal impact of earthquakes now, we should focus on developing the next generation of models that can provide better predictions of the strength and location of damaging ground shaking.

Extracts of the rat tapeworm, Hymenolepis diminuta, suppress macrophage activation in vitro and alleviate chemically induced colitis in mice.

Analysis of parasite-host interactions can reveal the intricacies of immunity and identify ways to modulate immunopathological reactions. We assessed the ability of a phosphate-buffered saline-soluble extract of adult Hymenolepis diminuta to suppress macrophage (human THP-1 cell line, murine peritoneal macrophages) activity in vitro and the impact of treating mice with this extract on colitis induced by dinitrobenzene sulfonic acid (DNBS). A high-molecular-mass fraction of adult H. diminuta (HdHMW) or excretory/secretory products reduced macrophage activation: lipopolysaccharide (LPS)-induced interleukin-1beta (IL-1beta), IL-6, and tumor necrosis factor alpha (TNF-alpha) and poly(I:C)-induced TNF-alpha and IL-6 were suppressed by HdHMW. The active component in the HdHMW extract was minimally sensitive to boiling and trypsin digestion, whereas the use of sodium metaperiodate, as a general deglycosylation strategy, indicated that the immunosuppressive effect of HdHMW was at least partially dependent on a glycan: treating the HdHMW with neuraminidase and alpha-mannosidase failed to inhibit its blockade of LPS-induced TNF-alpha production by THP-1 macrophages. Mice treated with DNBS developed colitis, as typified by wasting, shortening of the colon, macroscopic and microscopic tissue damage, and an inflammatory infiltrate. Mice cotreated with HdHMW (three intraperitoneal injections) displayed significantly less inflammatory disease, and this was accompanied by reduced TNF-alpha production and increased IL-10 and IL-4 production by mitogen-stimulated spleen cells. However, cotreatment of mice with neutralizing anti-IL-10 antibodies had only a minor impact on the anticolitic effect of the HdHMW. We speculate that purification of the immunosuppressive factor(s) from H. diminuta has the potential to lead to the development of novel immunomodulatory drugs to treat inflammatory disease.

FMRFamide-like peptides in root knot nematodes and their potential role in nematode physiology.

FMRFamide-like peptides (FLPs) are a diverse group of neuropeptides that are expressed abundantly in nematodes. They exert potent physiological effects on locomotory, feeding and reproductive musculature and also act as neuromodulators. However, little is known about the specific expression patterns and functions of individual peptides. The current study employed rapid amplification of cDNA ends-polymerase chain reaction (RACE-PCR) to characterize flp genes from infective juveniles of the root knot nematodes, Meloidogyne incognita and Meloidogyne minor. The peptides identified from these transcripts are sequelogs of FLPs from the free-living nematode, Caenorhabditis elegans; the genes have therefore been designated as Mi-flp-1, Mi-flp-7, Mi-flp-12, Mm-flp-12 and Mi-flp-14. Mi-flp-1 encodes five FLPs with the common C-terminal moiety, NFLRFamide. Mi-flp-7 encodes two copies of APLDRSALVRFamide and APLDRAAMVRFamide and one copy of APFDRSSMVRFamide. Mi-flp-12 and Mm-flp-12 encode the novel peptide KNNKFEFIRFamide (a longer version of RNKFEFIRFamide found in C. elegans). Mi-flp-14 encodes a single copy of KHEYLRFamide (commonly known as AF2 and regarded as the most abundant nematode FLP), and a single copy of the novel peptide KHEFVRFamide. These FLPs share a high degree of conservation between Meloidogyne species and nematodes from other clades, including those of humans and animals, perhaps suggesting a common neurophysiological role which may be exploited by novel drugs. FLP immunoreactivity was observed for the first time in Meloidogyne, in the circumpharyngeal nerve ring, pharyngeal nerves and ventral nerve cord. Additionally, in situ hybridization revealed Mi-flp-12 expression in an RIR-like neuron and Mi-flp-14 expression in SMB-like neurons, respectively. These localizations imply physiological roles for FLP-12 and FLP-14 peptides, including locomotion and sensory perception.

The effect of training order on neuromuscular, endocrine and mood response to small-sided games and resistance training sessions over a 24-h period.

OBJECTIVES: This study examined the acute effect of small-sided-game (SSG) and resistance training sequence on neuromuscular, endocrine and mood response over a 24-h (h) period. DESIGN: Repeated measures. METHODS: Fourteen semi-professional soccer players performed SSG-training (4vs4+goalkeepers; 6×7-min, 2-min inter-set recovery) followed by resistance training 2h later (back-squat, Romanian deadlift, barbell-hip-thrust; 4×4 repetitions, 4-min inter-set recovery; 85% 1 rep-max) (SSG+RES), and on a separate week reversed the session order (RES+SSG). Physical demands of SSG's were monitored using global positioning systems (GPS) and ratings of perceived exertion (RPE). Countermovement-jump (CMJ; peak power output; jump height) and brief assessment of mood were collected before (pre), during (0h) and after (+24h) both protocols. Salivary testosterone and cortisol concentrations were obtained at the same time-points but with the inclusion of a measure immediately prior to the second training session (+2h). RESULTS: GPS outputs and RPE were similar between SSG-training during both protocols. Between-protocol comparisons revealed no significant differences at +24h in CMJ performance, mood, and endocrine markers. Testosterone was higher at 0h during RES+SSG in comparison to SSG+RES (moderate-effect; +21.4±26.7pgml-1; p=0.010), yet was similar between protocols by +2h. CONCLUSIONS: The order of SSG and resistance training does not appear to influence the physical demands of SSG's with sufficient recovery between two sessions performed on the same day. Session order did not influence neuromuscular, endocrine or mood responses at +24h, however a favourable testosterone response from the resistance first session may enhance neuromuscular performance in the second session of the day.

The neuromuscular, endocrine and mood responses to a single versus double training session day in soccer players.

OBJECTIVES: This study profiled the 24h neuromuscular, endocrine and mood responses to a single versus a double training day in soccer players. DESIGN: Repeated measures. METHODS: Twelve semi-professional soccer players performed small-sided-games (SSG's; 4 vs 4+goalkeepers; 6×7-min, 2-min inter-set recovery) with neuromuscular (peak-power output, PPO; jump height, JH), endocrine (salivary testosterone, cortisol), and mood measures collected before (pre) and after (0h, +24h). The following week, the same SSG protocol was performed with an additional lower body strength training session (back-squat, Romanian deadlift, barbell hip thrust; 4×4 repetitions, 4-min inter-set recovery; 85% 1 rep-max) added at 2h after the SSG's. RESULTS: Between-trial comparisons revealed possible to likely small impairments in PPO (2.5±2.2Wkg-1; 90% Confidence Limits: ±2.2Wkg-1), JH (-1.3; ±2.0cm) and mood (4.6; ±6.1AU) in response to the double versus single sessions at +24h. Likely to very likely small favourable responses occurred following the single session for testosterone (-15.2; ±6.1pgml-1), cortisol (0.072; ±0.034ugdl-1) and testosterone/cortisol ratio (-96.6; ±36.7AU) at +24h compared to the double session trial. CONCLUSIONS: These data highlight that performance of two training sessions within a day resulted in possible to very likely small impairments of neuromuscular performance, mood score and endocrine markers at +24h relative to a single training session day. A strategy of alternating high intensity explosive training days containing multiple sessions with days emphasising submaximal technical/tactical activities may be beneficial for those responsible for the design and delivery of soccer training programs.

Use of the eLogbook in surgical training in the United Kingdom: A nationwide survey and consensus recommendations from the Association of Surgeons in Training.

INTRODUCTION: Accurate recording of operative cases is essential during training to demonstrate experience. However, indicative numbers delineating minimum desirable experience may incentivise exaggeration or misrepresentation of experience. This study aimed to determine perceptions of real-world eLogbook use among UK surgeons in training. MATERIAL AND METHODS: An anonymous online questionnaire was disseminated electronically using a pre-planned yield-maximisation strategy, incorporating regional champions, email and social media. Evaluation employed mixed methods in a combined interpretation of quantitative and qualitative data from the questionnaire. Recommendations for development of the eLogbook were itemised from respondents' free text items and a modified Delphi process, conducted within the Council of the UK national trainee representative body, the Association of Surgeons in Training, determined the strength of each recommendation. RESULTS: Analysis included 906 complete responses from training-grade surgeons (34.8% female) from all UK recognised specialties and all grades of training. More than two-thirds (68.5%) believed that overstatement or misrepresentation of case involvement occurs. A fifth (20.8%) reported witnessing trainees logging cases they had not actually participated in and almost a third (32.7%) had witnessed overstatement, yet few (15.1%) had raised such an issue with a supervisor. Most (85.2%) respondents had few or no eLogbook entries validated. More than a quarter of respondents felt pressure to overstate their involvement in cases (28.6%) and the number recorded (28.1%). Almost a third (31.5%) felt the required case number for completion of training was not achievable. Female trainees were less likely to feel well supervised (p = 0.022) and to perceive targets for completion of training were achievable (p = 0.005). Thematic analysis identified four key themes to explain logbook misuse: Pressure to achieve training milestones; eLogbook functionality issues; training deficiencies and probity. CONCLUSIONS: Inaccurate operative recording was widely reported, primarily in response to perceived pressure to achieve targets for career progression. Operative logbooks may not be as accurate as intended. Consensus recommendations are made for improvement in the eLogbook and its use.

Seismomagnetic observation during the 8 july 1986 magnitude 5.9 north palm springs earthquake.

A differentially connected array of 24 proton magnetometers has operated along the San Andreas fault since 1976. Seismomagnetic offsets of 1.2 and 0.3 nanotesla were observed at epicentral distances of 3 and 9 kilometers, respectively, after the 8 July 1986 magnitude 5.9 North Palm Springs earthquake. These seismomagnetic observation are the first obtained of this elusive but long-anticipated effect. The data are consistent with a seismomagnetic model of the earthquake for which right-lateral rupture of 20 centimeters is assumed on a 16-kilometer segment of the Banning fault between the depths of 3 and 10 kilometers in a region with average magnetization of 1 ampere per meter. Alternative explanations in terms of electrokinetic effects and earthquake-generated electrostatic charge redistribution seem unlikely because the changes are permanent and complete within a 20-minute period.

Tilt Precursors before Earthquakes on the San Andreas Fault, California.

An array of 14 biaxial shallow-borehole tiltmeters (at 1O(-7) radian sensitivity) has been installed along 85 kilometers of the San Andreas fault during the past year. Earthquake-related changes in tilt have been simultaneously observed on up to four independent instruments. At earthquake distances greater than 10 earthquake source dimensions, there are few clear indications of tilt change. For the four instruments with the longest records (> 10 months), 26 earthquakes have occurred since July 1973 with at least one instrument closer than 10 source dimensions and 8 earthquakes with more than one instrument within that distance. Precursors in tilt direction have been observed before more than 10 earthquakes or groups of earthquakes, and no similar effect has yet been seen without the occurrence of an earthquake.

The 1987 whittier narrows earthquake in the los angeles metropolitan area, california.

The Whittier Narrows earthquake sequence (local magnitude, M(L) = 5.9), which caused over $358-million damage, indicates that assessments of earthquake hazards in the Los Angeles metropolitan area may be underestimated. The sequence ruptured a previously unidentified thrust fault that may be part of a large system of thrust faults that extends across the entire east-west length of the northern margin of the Los Angeles basin. Peak horizontal accelerations from the main shock, which were measured at ground level and in structures, were as high as 0.6g (where g is the acceleration of gravity at sea level) within 50 kilometers of the epicenter. The distribution of the modified Mercalli intensity VII reflects a broad north-south elongated zone of damage that is approximately centered on the main shock epicenter.

Seismicity remotely triggered by the magnitude 7.3 landers, california, earthquake.

The magnitude 7.3 Landers earthquake of 28 June 1992 triggered a remarkably sudden and widespread increase in earthquake activity across much of the western United States. The triggered earthquakes, which occurred at distances up to 1250 kilometers (17 source dimensions) from the Landers mainshock, were confined to areas of persistent seismicity and strike-slip to normal faulting. Many of the triggered areas also are sites of geothermal and recent volcanic activity. Static stress changes calculated for elastic models of the earthquake appear to be too small to have caused the triggering. The most promising explanations involve nonlinear interactions between large dynamic strains accompanying seismic waves from the mainshock and crustal fluids (perhaps including crustal magma).

Parasitic helminths: a pharmacopeia of anti-inflammatory molecules.

SUMMARY: Infection with parasitic helminths takes a heavy toll on the health and well-being of humans and their domestic livestock, concomitantly resulting in major economic losses. Analyses have consistently revealed bioactive molecules in extracts of helminths or in their excretory/secretory products that modulate the immune response of the host. It is our view that parasitic helminths are an untapped source of immunomodulatory substances that, in pure form, could become new drugs (or models for drug design) to treat disease. Here, we illustrate the range of immunomodulatory molecules in selected parasitic trematodes, cestodes and nematodes, their impact on the immune cells in the host and how the host may recognize these molecules. There are many examples of the partial characterization of helminth-derived immunomodulatory molecules, but these have not yet translated into new drugs, reflecting the difficulty of isolating and fully characterizing proteins, glycoproteins and lipid-based molecules from small amounts of parasite material. However, this should not deter the investigator, since analytical techniques are now being used to accrue considerable structural information on parasite-derived molecules, even when only minute quantities of tissue are available. With the introduction of methodologies to purify and structurally-characterize molecules from small amounts of tissue and the application of high throughput immunological assays, one would predict that an assessment of parasitic helminths will yield a variety of novel drug candidates in the coming years.

The differential effect of sub-micron level HA aggregates on influenza potency assays.

Influenza vaccines remain the most effective public health measure for the prevention of influenza-related illnesses. The primary immunogen in inactivated influenza vaccines is hemagglutinin (HA), the receptor binding protein of influenza. The concentration of HA during vaccine production and testing is standardized according to the level of antigen as measured by Single Radial Immunodiffusion Assay (SRID). This allows vaccine potency to be controlled such that individuals receive a dose known to provoke a clinically protective immune response. As compared to alternatives, SRID has the advantage of quantifying immunologically relevant forms of HA, but it depends on timely generation of novel reagents for each new vaccine strain. In recent years, a number of alternative assays have been suggested based on either epitope recognition, receptor binding or protection from proteolysis but it is unclear how they relate to vaccine potency in clinical trials. In this report we describe the development of a lectin-based, ELISA-type assay for HA potency and find it provides similar potency estimates to SRID except in the case of a vaccine with aggregated HA and other viral proteins. In that case, SRID predicted the immunologically active HA present and ELISA techniques did not. This difference was due to tested antibodies failing to pull down or bind to the HA present unless particle aggregates were first dissociated. Furthermore, detergent treatment alone was insufficient to complete this dissociation. While others have previously demonstrated that immunocapture-based techniques can misestimate the potency of influenza vaccines depending on the individual antibodies used we demonstrate that in this case the failure was due to an inability of all antibodies to capture HA contained in the aggregated influenza vaccine.

Efficacy of thiopurines and adalimumab in preventing Crohn's disease recurrence in high-risk patients - a POCER study analysis.

BACKGROUND: Crohn's disease recurs in the majority of patients after intestinal resection. AIM: To compare the relative efficacy of thiopurines and anti-TNF therapy in patients at high risk of disease recurrence. METHODS: As part of a larger study comparing post-operative management strategies, patients at high risk of recurrence (smoker, perforating disease, ≥2nd operation) were treated after resection of all macroscopic disease with 3 months metronidazole together with either azathioprine 2 mg/kg/day or mercaptopurine 1.5 mg/kg/day. Thiopurine-intolerant patients received adalimumab induction then 40 mg fortnightly. Patients underwent colonoscopy at 6 months with endoscopic recurrence assessed blind to treatment. RESULTS: A total of 101 patients [50% male; median (IQR) age 36 (25-46) years] were included. There were no differences in disease history between thiopurine- and adalimumab-treated patients. Fifteen patients withdrew prior to 6 months, five due to symptom recurrence (of whom four were colonoscoped). Endoscopic recurrence (Rutgeerts score i2-i4) occurred in 33 of 73 (45%) thiopurine vs. 6 of 28 (21%) adalimumab-treated patients [intention-to-treat (ITT); P = 0.028] or 24 of 62 (39%) vs. 3 of 24 (13%) respectively [per-protocol analysis (PPA); P = 0.020]. Complete mucosal endoscopic normality (Rutgeerts i0) occurred in 17/73 (23%) vs. 15/28 (54%) (ITT; P = 0.003) and in 27% vs. 63% (PPA; P = 0.002). The most advanced disease (Rutgeerts i3 and i4) occurred in 8% vs. 4% (thiopurine vs. adalimumab). CONCLUSIONS: In Crohn's disease patients at high risk of post-operative recurrence adalimumab is superior to thiopurines in preventing early disease recurrence.

Histamine-induced increases in cyclic AMP levels in bovine adrenal medullary cells.

1. The effect of histamine on cellular cyclic AMP levels in cultured bovine adrenal medullary cells has been studied. 2. Histamine (0.3-30 microM) increased cyclic AMP levels transiently, with a maximal response after 5 min, a smaller response after 20 min, and no increase seen after 80 or 180 min. The EC50 at 5 min was approximately 2 microM. Histamine had no effect on cyclic AMP release from the cells over 5 min, but increased it after 90 min. 3. The cyclic AMP response to 5 microM histamine was reduced by 45% by 1 microM mepyramine and by almost 30% by 1 microM cimetidine, and was abolished by the combination of both antagonists. Cimetidine at 100 microM did not inhibit the response to histamine more than 1 microM cimetidine. The H3-receptor antagonist, thioperamide (1 microM), had no effect on the response to histamine. 4. The H1-receptor agonist, 2-thiazolyethylamine (5-100 microM) and the H2-receptor agonist, dimaprit (5-100 microM), each induced a cyclic AMP response, and gave more-than-additive responses when combined. The H3 agonist (R) alpha-methylhistamine (100 microM) had no effect either on its own or in combination with either the H1 or the H2 agonist. The response to 100 microM 2-thiazolylethylamine was unaffected by cimetidine (100 microM). 5. The cyclic AMP responses to 5 microM histamine, 100 microM thiazolylethylamine and 100 microM dimaprit were each weakly enhanced in the presence of 1 mM 3-isobutyl-1-methylxanthine. The response to dimaprit was enhanced more than 10 fold in the presence of 0.3 microM forskolin, while the responses to histamine and thiazolylethylamine were weakly enhanced.6. The cyclic AMP response to 5 microM histamine was partially reduced in the absence of extracellular Ca2 and the residual response was fully antagonized by 1 microM cimetidine and was unaffected by 1 microM mepyramine.In the absence of Ca2 , the cyclic AMP response to 100 microM thiazolylethylamine was abolished, while that to 100 microM dimaprit was unaffected.7. Reincubation of 5 microM histamine solutions with a second set of chromaffin cells, following prior incubation with another set of cells, induced a cyclic AMP response in the fresh cells. This response was reduced by a combination of mepyramine and cimetidine to the same degree as the response to fresh 5 microm histamine solutions.8. The results indicate that histamine increases cellular cyclic AMP levels in bovine chromaffin cells by three mechanisms: by acting on H1 receptors, by acting on H2 receptors, and by an interaction between H, and H2 receptors. The H1 response does not require concomitant activation of H2 receptors, is fully dependent on extracellular Ca2 +, does not depend on secreted chromaffin cell products, and is not due to reduced cyclic AMP degradation or export. The H2 cyclic AMP response is the first functional response reported for H2 receptors on chromaffin cells, is independent of Ca2 , is not due to reduced cyclic AMP export or degradation, and is likely to be mediated via a direct action through Gs. The role of these different mechanisms in the regulation of cyclic AMP-dependent processes in chromaffin cells by histamine is under investigation.

INR reporting in Canadian medical laboratories: an update. Thrombosis Interest Group of Canada.

A written survey of all licensed medical laboratories performing coagulation testing in Canada was undertaken in 1996 as a follow-up to a study performed in 1992. The an overall response rate was 77.4% of the laboratories surveyed. During the 4-year period between surveys, the percentage of responding laboratories using some format for international normalized ratio (INR) reporting increased from 57% to 98%. The mean International Sensitivity Index (ISI) of the various thromboplastins used had decreased from 2.07 to 1.63. However, only 35% of responding laboratories used a thromboplastin with an ISI of 1.2 or less as recommended by the American College of Chest Physicians. In 92% of cases, the ISI was said to be specified for the type of instrument, ie, optical density vs mechanical. However, in only 52% of cases was the ISI known to be specific for the particular reagent-analyzer combination used in the individual laboratory. Nine percent of the laboratories were still using an inappropriate denominator for the INR calculation. While 87% of laboratories quoted a therapeutic INR range of 2.0 to 3.0 for venous thromboembolism, there was much greater variation in the range reported for patients undergoing heart valve replacement. The situation in Canada has improved in using the INR system for prothrombin time reporting. However, additional education is required, as is greater use of thromboplastins with a lower ISI.

Does human papilloma virus have a role in squamous cell carcinoma of the colon and upper rectum?

AIM: To determine if Human Papilloma Virus (HPV) has a role in the aetiology of adenosquamous and squamous cell carcinoma of the colon and upper rectum, and to describe the clinical features seen in our patients with this condition. METHODS: Patients were identified with squamous cell carcinoma (SCC), adenosquamous carcinoma (Ad-SCC), or adenocarcinoma with squamous metaplasia (AA) of the colon and upper rectum over the 10 years from 1/1/1990 to 31/12/1999. Patients were identified from a prospective pathology database. All tumours were at least 5cm above the dentate line. Pathology blocks were stained using the Peroxidase labelled Streptavidin technique using mouse monoclonal antibody NCL-HPV-4C4, which identifies HPV 6, 11, 16 and 18. Age, gender and site matched controls (colorectal adenocarcinomas) were also stained. The clinical presentation and management was reviewed from the case notes. RESULTS: Twenty patients were identified from a pathological database of 2351 colorectal cancers (0.85% of colorectal cancers). 0/20 of the study patients (SCC, Ad-SCC, AA) or adenocarcinoma controls stained positively for HPV 6, 11, 16, 18. The clinical presentation was similar to patients presenting with adenocarcinomas. CONCLUSIONS: The peroxidase labelled streptavidin technique is an immunohistochemical technique with high specificity but lower sensitivity. There was no apparent association between HPV 6, 11, 16, 18 and squamous cell and adenosquamous carcinoma of the colon and rectum using this technique. Clinical features are similar in squamous and adenosquamous colorectal carcinomas to colorectal adenocarcinomas.