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The NanoMine database, one of two nodes in the MaterialsMine database, is a new materials data resource that collects annotated data on polymer nanocomposites (PNCs). This work showcases the potential of NanoMine and other materials data resources to assist fundamental materials understanding and therefore rational materials design. This specific case study is built around studying the relationship between the change in the glass transition temperature Tg(ΔTg) and key descriptors of the nanofillers and the polymer matrix in PNCs. We sifted through data from over 2000 experimental samples curated into NanoMine, trained a decision tree classifier to predict the sign of PNC ΔTg, and built a multiple power regression metamodel to predict ΔTg. The successful model used key descriptors including composition, nanoparticle volume fraction, and interfacial surface energy. The results demonstrate the power of using aggregated materials data to gain insight and predictive capability. Further analysis points to the importance of additional analysis of parameters from processing methodologies and continuously adding curated data sets to increase the sample pool size.

There are concerns that the COVID-19 pandemic has had a negative effect on cancer care but there is little direct evidence to quantify any effect. This study aims to investigate the impact of the COVID-19 pandemic on the detection and management of colorectal cancer in England.

Examining underage drinking contexts can advance the field of adolescent substance use prevention by supporting and informing interventions that can target adolescents in specific contexts. The current study examines how concurrent and lagged situational (i.e., alcohol availability and adult supervision), social (i.e., the number of people and presence of friends), and location (i.e., home vs other location) context characteristics change risks for alcohol use over the night course. Text messages with links to online surveys were used to collect ecological momentary assessment (EMA) data over 2 weekends from adolescents in California. Data were collected using adolescents’ personal cell phones early and late in the evening and the following morning. Analyses were limited to adolescents with at least 1 drinking occasion during EMA (N= 58; Mage = 16.64, SD = 0.74; 48% female; 83% White). Drinking earlier in the evening was positively associated with continued drinking over the night course. Context characteristics were found to play important concurrent and lagged roles in increasing the likelihood of alcohol use over evening hours. Findings indicated substantive concurrent and lagged social, situational, and location‐based contextual effects on adolescent alcohol use over the course of an evening. Importantly, context characteristics were differentially associated with alcohol use over the course of the evening. The fact that these contextual factors are modifiable suggests that the use of prevention strategies delivered to adolescents throughout the evening may reduce adolescents’ drinking and related problems over the evening hours. We examined how concurrent and lagged context characteristics change risks for alcohol use among adolescents over the night course. Using an ecological momentary assessment data, results show that situational (i.e., alcohol availability and adult supervision), social (i.e., the number of people and presence of friends), and location (i.e., home settings) context characteristics change risks for adolescents’ nighttime alcohol use. Results suggest that the use of prevention strategies delivered throughout the evening hours may reduce adolescents’ drinking and related problems.

Objective:This article provides a systematic review of cross-sectional research examining associations between exposure to alcohol marketing and alcohol use behaviors among adolescents and young adults.Method:Literature searches of eight electronic databases were carried out in February 2017. Searches were not limited by date, language, country, or peer-review status. After abstract and full-text screening for eligibility and study quality, 38 studies that examined the relationship between alcohol marketing and alcohol use behaviors were selected for inclusion.Results:Across alcohol use outcomes, various types of marketing exposure, and different media sources, our findings suggest that cross-sectional evidence indicating a positive relationship between alcohol marketing exposure and alcohol use behaviors among adolescents and young adults was greater than negative or null evidence. In other words, cross-sectional evidence supported that alcohol marketing exposure was associated with young peoples’ alcohol use behaviors. In general, relationships for alcohol promotion (e.g., alcohol-sponsored events) and owning alcohol-related merchandise exposures were more consistently positive than for other advertising exposures. These positive associations were observed across the past four decades, in countries across continents, and with small and large samples.Conclusions:Despite issues of measurement and construct clarity within this body of literature, this review suggests that exposure to alcohol industry marketing may be important for understanding and reducing young peoples’ alcohol use behavior. Future policies aimed at regulating alcohol marketing to a greater extent may have important short- and long-term public health implications for reducing underage or problematic alcohol use among youth.

ObjectiveWe conducted meta-analyses of studies that investigated the associations between tobacco outlet density around homes and schools and adolescents’ past-month cigarette smoking.Data sourcesSystematic literature searches of eight databases were carried out in February 2017. Searches were not limited by date, language, country or peer-reviewed status.Study selectionAfter screening for quality, studies that examined the relationship between tobacco outlet density and adolescents’ past-month smoking were selected for inclusion.Data extractionTwo investigators screened study abstracts and full texts and independently extracted data. Consensus was reached at each stage.Data synthesisRandom-effects meta-analyses were conducted on 11 studies that provided 13 effect sizes. Results showed that there was a significant association between tobacco outlet density around homes and adolescents’ past-month smoking behaviour, with an overall effect size of OR=1.08 (95% CI 1.04 to 1.13; P<0.001; I2=0%). For density around schools, the association was not statistically significant (OR=1.01, 95% CI 0.98 to 1.03; P=0.53; I2=39%).ConclusionsThese findings suggest that exposure to tobacco outlets near home environments may be important for understanding adolescents’ past-month smoking. Restricting access to tobacco outlets and controlling the number of outlets in residential areas may be an effective preventive strategy to help reduce adolescents’ smoking.

ObjectiveIn 2001, the National Institute for Health Research Cancer Research Network (NCRN) was established, leading to a rapid increase in clinical research activity across the English NHS. Using colorectal cancer (CRC) as an example, we test the hypothesis that high, sustained hospital-level participation in interventional clinical trials improves outcomes for all patients with CRC managed in those research-intensive hospitals.DesignData for patients diagnosed with CRC in England in 2001–2008 (n=209 968) were linked with data on accrual to NCRN CRC studies (n=30 998). Hospital Trusts were categorised by the proportion of patients accrued to interventional studies annually. Multivariable models investigated the relationship between 30-day postoperative mortality and 5-year survival and the level and duration of study participation.ResultsMost of the Trusts achieving high participation were district general hospitals and the effects were not limited to cancer ‘centres of excellence’, although such centres do make substantial contributions. Patients treated in Trusts with high research participation (≥16%) in their year of diagnosis had lower postoperative mortality (p<0.001) and improved survival (p<0.001) after adjustment for casemix and hospital-level variables. The effects increased with sustained research participation, with a reduction in postoperative mortality of 1.5% (6.5%–5%, p<2.2×10−6) and an improvement in survival (p<10−19; 5-year difference: 3.8% (41.0%–44.8%)) comparing high participation for ≥4 years with 0 years.ConclusionsThere is a strong independent association between survival and participation in interventional clinical studies for all patients with CRC treated in the hospital study participants. Improvement precedes and increases with the level and years of sustained participation.

ABSTRACTBackground:Early onset of alcohol use has been linked to later alcohol problems in adulthood. Currently, it is not clear whether early onset of marijuana and tobacco use similarly predicts alcohol problems. Moreover, most studies examining the effect of early substance use onset on later problems only have followed youth into their early 20s. Therefore, the primary goal of this study was to examine whether early onset of alcohol, marijuana, and tobacco use predicts alcohol problems beyond the transition to adulthood. Methods:The sample included 225 15–19-year-old youth (60% girls; 62% Caucasian) who were surveyed in three time periods: 1993–1998 (Time 1), 1998–2003 (Time 2), and 2003–2007 (Time 3). Participants reported their age of onset for regular drinking, tobacco use, and marijuana use. At each time of measurement, they also completed surveys relating to their alcohol use and abuse. Results:Participants with an earlier age of onset of drinking regularly scored higher on the Michigan Alcoholism Screening Test (MAST) and drank more frequently to get high and drunk throughout their 20s. Tobacco use onset and marijuana use onset were not associated with later alcohol use or abuse. Conclusions:Results from this study suggest that the relationship between the onset of substance use and later substance abuse may be substance specific. Of note, early onset of regular drinking was associated with alcohol problems during adulthood, underscoring the importance of delaying the onset of regular alcohol use among youth.

Background Early onset of alcohol use has been linked to later alcohol problems in adulthood. Currently, it is not clear whether early onset of marijuana and tobacco use similarly predicts alcohol problems. Moreover, most studies examining the effect of early substance use onset on later problems only have followed youth into their early 20s. Therefore, the primary goal of this study was to examine whether early onset of alcohol, marijuana, and tobacco use predicts alcohol problems beyond the transition to adulthood.Methods The sample included 225 15–19-year-old youth (60% girls; 62% Caucasian) who were surveyed in three time periods: 1993–1998 (Time 1), 1998–2003 (Time 2), and 2003–2007 (Time 3). Participants reported their age of onset for regular drinking, tobacco use, and marijuana use. At each time of measurement, they also completed surveys relating to their alcohol use and abuse.Results Participants with an earlier age of onset of drinking regularly scored higher on the Michigan Alcoholism Screening Test (MAST) and drank more frequently to get high and drunk throughout their 20s. Tobacco use onset and marijuana use onset were not associated with later alcohol use or abuse.Conclusions Results from this study suggest that the relationship between the onset of substance use and later substance abuse may be substance specific. Of note, early onset of regular drinking was associated with alcohol problems during adulthood, underscoring the importance of delaying the onset of regular alcohol use among youth.

Colorectal cancer spreads to lymph nodes via surrounding lymphatic vasculature. Once this spread has occurred, the prognosis of the patient is significantly worse. Lymphatics are difficult to identify on hematoxylin and eosin stains and lack of specific markers has meant that little is known about their distribution in colorectal tissue. The national bowel cancer screening program has resulted in an increase in the diagnosis of T1 colorectal cancers. Patients with suitable T1 tumors can avoid bowel resections and their associated morbidity with the advances in local resection techniques. This means, however, that formal staging and lymph node assessment cannot be performed. Prognostic tools are required to predict risk of lymph node metastases. Studies assessing risk of lymph node spread in T1 tumors have found that invasion of the tumor into the deepest third of the submusosa affords a much greater risk. We hypothesized that this might be due to the quantity or characteristics of lymphatic vasculature in this third.

The size and contents of the pelvis differ between the genders, and this may affect mesorectal size and shape. The aim of this prospective pilot study was to examine radiologically the applied anatomy of the mesorectum.

Climate studies have traditionally fallen within the purview of the natural sciences where cause and predictable pattern are sought for such phenomena as climate change and climate variability. In the past, social scientists had little occasion to cross disciplinary paths with atmospheric or oceanographic scientists. Not that social science has ignored climate, for anthropology and geography claim a rich literature on the impacts of climate variability, particularly drought, on human populations (e.g., Franke and Chasin 1980; Watts 1983; Langworthy and Finan 1997). New theoretical ground, fertilized by an increasing number of empirical studies, now promises to bear the fruit we call climate anthropology. The expanding social science agenda has responded to two relatively recent advances in the natural sciences. The first has been the widening scientific consensus regarding global climate change and its anthropogenic causes. Global change cannot be adequately characterized without understanding the human-environment interactions that have contributed to the phenomenon, forcing social and natural scientists to pursue common research objectives. The second influence on climate anthropology has been the improvement in scientific understanding of oceanic/atmospheric interactions, thus allowing for more refined predictability of climatic events, particularly extreme ones. It is with this advance in climate predictability that climate anthropology is beginning to reap an exceedingly bountiful harvest in both theory and application.

Thirty consecutive patients had laboratory assessment of anorectal function after rectal excision and stapled coloanal anastomosis for rectal carcinoma. Eleven patients experienced perfect continence but 19 had faecal leakage with or without urgency of defaecation. Median (interquartile range) function was related to the pressures generated in the anal sphincter at rest (good versuspoor function: 80 (63–91) versus51 (23–60) cmH2O, P<0±01), during maximum squeeze (160 (126-203) versus102 (58-112) cmH2O, P<0±01) and during reflex inhibition (58 (23-63) versus36 (18-54) cmH2O, P<0±05). Poor function was significantly commoner in women than in men (P<0±01). These findings suggest that occult damage may have occurred to the anal sphincter before low anterior resection. Careful preoperative evaluation with manometry and endoanal ultrasonography may detect such damage and allow selection of patients for colopouch reconstruction.

A study was conducted to assess the genetic contribution to the development of colorectal cancer in young probands. Of 83 patients aged 45 years or under diagnosed with colorectal cancer in one health region over a 2-year period, 65 or their surviving next of kin were available for interview, from whom were obtained 60 detailed and five limited family histories. Five families fulfilled the Amsterdam criteria and a further eight satisfied less strict criteria for hereditary non-polyposis colorectal cancer, a total of 20 per cent of the cohort. Eleven of these families came from the subgroup of 13 probands who had one or more first-degree relatives with colorectal cancer. Overall the relative risk of colorectal cancer in close relatives was 5·2 (P<0·0001). This risk was highest for female relatives at 9·7 (P<0·0001) and relatives of female probands at 6·7 (P<0·0001). This study highlights the importance of taking a family history in this group of patients. Screening by colonoscopy for all close relatives of young patients with colorectal cancer is recommended.

This study investigated the relationships between length of residual anorectum, anorectal physiological function and clinical outcome after anterior resection for rectal carcinoma. Thirty-four patients were studied a median of 13 (range 4–100) months after anterior resection. They were compared with a control group often patients who had undergone sigmoid colectomy for carcinoma without rectal excision. Resting anal pressure was found to be lower after coloanal than after colorectal anastomosis, and the capacity of the (neo)rectum was less after coloanal than after colorectal anastomosis. The (neo)rectoanal inhibitory reflex was found to be present in each patient, but maximum anal pressure during this “sampling” reflex was significantly lower (P< 0.01) after coloanal than after colorectal anastomosis, and the volume required for maximal inhibition of the sphincter was also less (P< 0.01). At 1 year after operation, median bowel frequency was greater after coloanal (4 per day) than after colorectal (2 per day) anastomosis and the degree of urgency of defaecation was also greater (P< 0.01). Quality of life in terms of anorectal function after anterior resection is thus significantly influenced by the length of rectum that is left. This, in turn, influences the functional capacity of the neorectum and the degree of inhibition of the anal sphincter during the neorectoanal inhibitory reflex.

Familial clustering of cancer is not uncommon. The frequency of familial colorectal cancer was estimated by taking family histories from 100 patients presenting with apparently sporadic colorectal cancer. Compared with controls, the relative risk of a positive family history for colorectal cancer was 4·6. Life-table methods were used to examine the observed to expected mortality from colorectal cancer. Overall there was a fourfold increase in mortality rate (P< 0·0001), which was greatest in female relatives of patients with colonic cancer (P< 0·001). Three families with dominant inheritance of colorectal cancer and one family with Lynch type II syndrome were identified. Nine per cent of patients had siblings who had developed colorectal cancer a median of 4 years before the diagnosis of the index patient (range 1–17 years). It is recommended that a careful family history should be obtained from all patients with colorectal cancer. Where a positive history is obtained a geneticist may determine empirical risks for the development of colorectal cancer and the appropriate method of surveillance may be selected.

A review of 90 patients presenting in Leeds over the period 1976-80 with synchronous hepatic metastases from colorectal cancer has been undertaken. The median survival for the group was 10.3 months (range 1–48 months). A multivariate analysis identified factors in the history and examination of the patient, results of biochemical and haematological investigations and characteristics of both the primary and secondary tumour, which influenced survival. Recognition of these factors allowed both a clinical scoring index and computer survival model to be constructed. When applied to the group as a whole both were reasonably accurate at predicting survival (62 per cent for the survival model and 66 per cent for the scoring index). However, the computer model correctly identified 80 per cent of the long-term survivors (> 12 months from the time of diagnosis). It is concluded that many trials of therapy for hepatic metastases from colorectal cancer have failed to consider the natural history of the disease and the identification of prognostic indices should allow for adequate stratification within the treatment arms of any future study.

Pre-operative staging of rectal cancer might define patients with disease confined to the rectal wall without lymph node metastases, in whom local excision might be appropriate, or patients with extrarectal spread, who might benefit from pre-operative radiotherapy. With these objectives, 36 consecutive patients with rectal cancer were studied by endoluminal ultrasound: 17 of them also underwent computed tomography (CT) of the pelvis. The results were correlated with the findings at operation and subsequent pathological examination. Endoluminal ultrasound correctly predicted invasion of the tumour through the rectal wall in 86 per cent of patients, with a sensitivity of 96 per cent and specificity of 50 per cent, but correctly identified lymph node metastases in only 61 per cent of patients (sensitivity 57 per cent; specificity 64 per cent). CT correctly predicted invasion through the rectal wall in 94 per cent of cases, with a sensitivity of 100 per cent and specificity of 67 percent and correctly identified lymph node metastases in 70 per cent of patients (sensitivity 25 per cent; specificity 85 per cent). These findings indicate that both endoluminal ultrasound and CT may be helpful in selecting patients for pre-operative radiotherapy. Neither technique, however, can reliably identify lymph node metastases and therefore cannot be used to select patients who would be suitable for local excision.

PURPOSE: The aim of this study was to examine the serial changes that take place in the first year after low anterior resection for rectal carcinoma, in terms both of anorectal physiology and clinical bowel function. Our hypothesis was that some patients never regain satisfactory anorectal function, because the operative procedure leads to permanent impairment of anorectal reflex and motor function. METHOD: Nineteen patients underwent serial tests of anorectal function, before and for one year after low anterior resection. The median level of the anastomosis above the anal high-pressure zone was 3 (range, 1–6) cm. RESULTS: Anal resting pressure (median (interquartile range)) was significantly decreased three months after operation (62 (46–72) cm H2O) and one year after operation was still significantly less (58 (48–73) cm H2O) than before operation (77 (58–93) cm H2O)(P<0.01). Maximum tolerated volume in the neorectum decreased from 130 (88–193) ml before operation to 80 (51–89) ml three months after operation (P<0.005) but returned to preoperative values by six months (125 (60–140) ml) (P=not significant) and remained at these values one year after operation. The volume in the “neorectal” balloon required to elicit a maximum rectoanal inhibitory reflex was significantly less three months after operation than before operation (50 (43–60) ml compared with 100 (73–100) ml;P<0.005); one year after operation, the volume required was still significantly less than before operation (50 mlvs.100 ml) (P<0.015). Bowel frequency increased from 1 (1–2) in 24 hours before operation to 4 (2–5) times in 24 hours after operation and remained at 4 times in 24 hours throughout the first year after operation. Three months after operation, 53 percent of patients experienced some degree of fecal leakage and 24 percent experienced urgency of defecation. These aspects of bowel function improved with time, but even one year after operation, 29 percent of patients continued to experience fecal leakage and 18 percent wore a protective pad. CONCLUSIONS: Anal resting pressure decreased significantly after low anterior resection and did not recover in the course of the first year after operation. Moreover, the volume of an air-filled balloon in the neorectum that was required to elicit maximum inhibition of the anal sphincter was significantly less after anterior resection than before operation. These long-term and presumably permanent changes in physiologic behavior of the anoneorectum after low anterior resection provide an explanation for the failure of some patients to regain satisfactory bowel function following that procedure.

PURPOSE: The aim of this study was to examine the dynamic inter-relationship of the anal sphincter, residual rectum, and neorectum after low anterior resection for rectal carcinoma. METHODS: Seventy-three patients underwent laboratory tests of anorectal function a median often (range 1–100) months after operation. All patients completed quality of life questionnaires and had the level of their anastomoses determined by rigid sigmoidoscopy. Forty-four patients (60 percent) had some form of disturbance of bowel function, which was classified as “poor” function if bowel frequency was four or more in 24 hours and if there was also either fecal leakage or urgency of defecation. Manometric data were analyzed using stepwise logistic regression analysis. RESULTS: Only two factors were found to be significantly and independently associated with poor bowel function, namely, the pressure recorded in the upper part of the anal sphincter in response to distention of the neorectum (15 (7–24) cm of water in patients with poor functionvs.29 (15–58) cm in patients with good function;P<0.005) and the level of the anastomosis above the anal sphincteric high pressure zone (2.5 (2–3.5) cm in patients with poor functionvs.6 (4–12) cm in patients with good function;P<0.005). CONCLUSION: Continence after anterior resection is related to an appropriate “sampling” response in the anal sphincter to activity within the neorectum. This in turn, is directly related to length of the residual rectum, which is, therefore, of crucial importance to function.

PURPOSE: The aim of this study was to determine whether coordinated activity exists across a stapled enteroanal anastomosis. METHODS: Twenty-nine patients were studied for a median of one year after complete excision of the rectum and stapled enteroanal anastomosis; 12 patients underwent low anterior resection with coloanal anastomosis for carcinoma, and 17 patients underwent restorative proctocolectomy with ileoanal anastomosis. RESULTS: Maximum anal resting pressures were slightly lower after coloanal anastomosis than after ileoanal anastomosis [median range, 56 (11–60) cm H2O, cf 69 (40–107) cm H2O,P=NS]. During distention of the neorectum, anal sphincter pressures at 2.5, 1.5, and 0.5 cm from the anal verge were significantly lower after coloanal anastomosis compared with after ileoanal anastomosis (P<0.01 at each station). The volume of neorectal distention required to produce maximal inhibition of the anal sphincter was significantly less after coloanal anastomosis at 50 (range, 20–60) ml of air than after ileoanal anastomosis at 240 (range, 100–420) ml of air (P<0.01). Minor fecal leakage and urgency of bowel action were significantly more common after coloanal anastomosis (P<0.01). CONCLUSION: Alterations in the dynamic response of the anal sphincter to distention of the neorectum may explain why the clinical results were better after ileal pouch-anal anastomosis than after coloanal anastomosis.

Close relatives of patients with colorectal cancer are at an increased risk of developing a colorectal malignancy themselves. PURPOSE: A study was conducted to compare risks in relatives of patients diagnosed at different ages. METHODS: Family histories were taken from two cohorts of patients with colorectal cancer: Group A, a population group of 65 patients diagnosed at or under 45 (median, 42) years; Group B, 212 patients of all ages (median, 68 years) treated in a single surgeon's practice. RESULTS: Overall relative risk of colorectal cancer in first-degree relatives was 5.2 in Group A and 2.3 in Group B. There was familial clustering of colorectal cancers suggestive of hereditary nonpolyposis colorectal cancer in 13 (20 percent) families to Group A but to only 3 (1.5 percent) families in the second group. Cumulative incidence of colorectal cancer for relatives of the young cohort rose steeply from 40 years, reaching 5 percent at age 50 years and 10 percent at age 70 years. This contrasts with risk for relatives of older patients, in whom the shape of the curve resembles that of the overall population risk, reaching 5 percent at age 70 years and 10 percent at age 80 years. CONCLUSIONS: There appears to be a quantitative and qualitative increase in risk to relatives of patients diagnosed at a young age compared with those diagnosed later to life, at least part of which is likely to be the result of a hereditary susceptibility. Close relatives of early onset cases warrant more intensive endoscopic screening and at an earlier age than relatives of patients diagnosed at older ages.

This paper analyzes a large regional market for fruits and vegetables in Northeast Brazil. A single production zone, with its local network of middlemen, supplies three major urban centers. As in many other markets where risk is high and information restricted, these middlemen have developed “equilibrating” relationships to impose order on an uncertain environment. These relationships and their underlying logic are discussed here. These patterns of dyadic ties are related to individual success in the market and to the performance of the market system as a whole. The analysis suggests that market participants use familiar social instruments —such as reciprocity—to make sense of an uncertain economic environment.

Selected monoclonal antibodies (McAbs) isolated after immunization of rats with a human colonic carcinoma membrane preparation, have been screened on frozen and paraffin sections of colonic tissue, using immunohistochemical techniques, in order to provide additional information with regard to specificity and crossreactivity with normal tissues.Of 10 McAbs previously shown to bind to a colonic carcinoma membrane preparation in a radioimmunoassay, 7 show specific staining when tested by indirect immunofluorescence on crysotat sections of colonic tissue. Three of these 7 show activity on both normal and malignant colonic epithelium, and the remaining 4 stain normal epithelium, with little or no activity on malignant tissue. In the indirect immunofluorescent and immunoperoxidase techniques on paraffin sections of the same material, only 2 McAbs retain activity, one detects an antigen in colonic mucus, and the other recognises an antigen which is sparse on normal colonic epithelium and abundant on colonic tumours.We conclude that screening of McAbs on frozen tissue sections, using indirect immunofluorescence, is a useful adjunct to conventional screening methods, e.g. binding to membrane preparations and/or cell lines in a radioimmunoassay. These techniques distinguish McAbs with similar binding values in conventional assays, identify their activity on a wide range of normal and malignant tissues, demonstrate antigens that are lost or gained in malignant transformation and finally assist in the selection of McAbs for further extensive study before possible clinical use.

Eleven patients with infra-levator trans-sphincteric fistula-in-ano underwent fistula excision with rectal flap advancement. The clinical results were assessed by interview and the physiological function determined by ano-rectal manometry. Nine patients underwent paired studies before and 5 (range 2 to 6) months after operation. Median maximum resting anal pressure was 84 (48–135) cm water before operation and 76 (29–139) cm water after operation (P=N.S.). Median maximum squeeze pressure was 112 (64–290) cm water before operation and 88 (44–316) cm water after operation (P=N.S.). The median sphincter length was preserved after operation. There was one clinical failure following the development of an abscess under the flap. All patients are continent and there have been no recurrences. We conclude that rectal flap advancement is an acceptable way to cure more complex fistula-in-ano. Good functional results are achieved by maintaining anal sphincter function together with preservation of the integrity of the anal margin.

The aim of this study was to try to gauge the functional effect of post-operative adjuvant radiotherapy after potentially curative anterior resection for carcinoma of the rectum. Anorectal function was studied both in the laboratory and clinically in 59 patients, a median of 12 months (range 6–96) after operation. Nine patients received post-operative radiotherapy and 50 matched patients were treated by surgery alone. Though maximum resting anal pressures and maximum squeeze pressures were similar in the two groups of patients, the length and pressure profile of the anal sphincter were both markedly abnormal after radiotherapy. The capacity and compliance of the neorectum were diminished significantly after radiotherapy (maximum tolerated volume 53 ml vs 110 ml after surgery alone, P=0.008, compliance 1.5 ml/cm H2O vs 3.7 ml/cm H2O after surgery alone, p-0.018) and the amount of distension of the neorectum required to produced maximum inhibition of the anal sphincter during the rectoanal inhibitory reflex was also significantly diminished after radiotherapy (P=0.005). Clinical anorectal function was worse among patients who had received radiotherapy, a greater proportion of whom experienced both urgency of defaecation and varying degrees of incontinence. Major faecal leakage necessitating the use of a pad was recorded in 3 of the 59 patients after radiotherapy (one of whom required a permanent colostomy), but in only 5 of 50 patients after surgery alone.

Division of the inferior mesenteric artery flush with the aorta (high tie) allows a tension-free anastomosis in distal colorectal resections but may also diminish the blood supply. Tissue oxygen tension was measured proximal to the resection margin before and after either low or high division of the inferior mesenteric artery in 62 patients undergoing elective colorectal resections. Oxygenation was maintained or improved when the transverse (median change after vs before resection for low tie +9 mmHg (P<0.05), high tie+8 mmHg (P=0.3)) and descending colon (low tie +7 mmHg (p<0.01), high tie +1 mmHg (p=0.67)) were used for the anastomosis but diminished for sigmoid anastomoses (low tie-4 mmHg (P=0.42), high tie-9 mmHg (P<0.05)). Change in oxygenation was significantly affected by location of proximal resection site but not by choice of high or low tie. These results suggest that the marginal artery provides a more than adequate vascular supply to the transverse and descending colon, but that the sigmoid colon is not suitable for anastomosis. We conclude that the sigmoid colon be sacrificed and there should be no hesitation in performing a high tie to avoid tension in low pelvic anastomoses.

Hereditary nonpolyposis colorectal carcinoma (HNPCC) is a major cancer susceptibility syndrome known to be caused by inheritance of mutations in genes such as hMSH2 and bMLH1, which encode components of a DNA mismatch repair system. The MSH2 genomic locus has been cloned and shown to cover ∼73 kb of genomic DNA and to contain 16 exons. The sequence of all of the intron-exon junctions has been determined and used to develop methods for analyzing each MSH2 exon for mutations. These methods have been used to analyze two large HNPCC kindreds exhibiting features of the Muir-Torre syndrome and demonstrate that cancer susceptibility is due to the inheritance of a frameshift mutation in the MSH2 gene in one family and a nonsense mutation in the MSH2 gene in the other family.

The occurrence of agglutinating and precipitating antibodies to Candida species was determined in 50 patients undergoing operations on the large intestine. The number of patients with oral or faecal yeast colonization and the amount of faecal colonization increased during the period after operation. No patient developed overt fungal infection but 15 patients developed precipitins to mannan antigens and 9 patients developed precipitins to cytoplasmic antigens during this period. The association between the formation of precipitins and the extent of faecal colonization is discussed.

Total mesorectal excision (TME) appears to be associated with a reduced local recurrence rate following surgery for rectal cancer. Of 20 patients with rectal cancer in whom TME was performed, adenocarcinoma was found in the distal mesorectum in four. Distal mesorectal spread often extended further than intramural spread. Patients with tumour in the distal mesorectum had a worse outcome at 4-year follow-up, a greater risk of local recurrence and an increased frequency of distant metastasis. Distal tumour spread is, therefore, a marker of poor prognosis in rectal cancer. This study provides further evidence that incomplete excision of the mesorectum contributes to local recurrence in a proportion of patients with rectal cancer, particularly in those with tumours in the middle and lower third of the rectum.

A retrospective study of 645 cholecystectomies performed in a surgical unit over a 10-year period is presented, of which 236 were carried out during an acute admission. of these 236 cholecystectomies, 195 were performed for acute cholecystitis and 41 for acute gallstone pancreatitis. In the acute cholecystitis group the proportion of patients over 70 years of age was significantly higher (35 per cent) than the corresponding elective group (10.3 per cent). of those patients presenting with complications (empyema, gangrene, perforation, and biliary peritonitis) 51 per cent were over the age of 70 years. The most valuable investigation in the diagnosis of acute cholecystitis was ultrasound carried out within the first 48 h, with positive results in 83 per cent of those examined. The mortality for elective cholecystectomy was 0.5 per cent rising to 4.7 per cent in the urgent/early cholecystectomy group. The mean age of the 11 patients who died was 76 years, 8 of these patients being over the age of 70 years. The mortality in the subgroup of patients over 70 years was 10 per cent rising to 20 per cent in the over-80 age group. There were no deaths in the acute gallstone pancreatitis group. We conclude that emergency or early cholecystectomy is a safe procedure in patients under 70 years of age. However, patients over 70 years present with more serious complications of acute gallbladder disease which necessitate urgent surgery. We therefore recommend early cholecystectomy in patients over 70 years despite the high attendant mortality.

A prospective study to investigate the value of monoclonal antibody (McAb) immunoscintigraphy for the detection of primary tumours of the colon and rectum has been undertaken. Twelve patients received 1 mg 131I-labelled McAb YPC 2/12·1, an antibody raised to a human colonic carcinoma membrane preparation. Imaging of the blood pool was achieved using 99mTc-labelled red cells. After surgery specimens were scanned and samples of normal and malignant tissue excised to obtain antibody binding ratios. In only one patient was the primary tumour visualized pre-operatively. Images of the resected specimens revealed the primary tumour in ten cases but this appeared to be a function of increased blood pool within the tumour rather than specific antibody localization. The mean tumour/normal tissue count ratio was 1·27:1 (range 0·63:1–1·93:1). It is concluded that the McAb YPC 2/12·1 is unlikely to be of use clinically. Furthermore when selecting McAbs for the purposes of immunoscintigraphy the results of in vitrobinding to malignant cell lines, immunohistological studies and xenograft experiments may be misleading and careful clinical evaluation is necessary.

In a review of cases of colorectal cancer presenting to St. Mark's Hospital over the 16-year period 1970–85, 59 patients were found to have a synchronous carcinoma (3·4 per cent). Although 82 per cent of these synchronous tumours were distal to the splenic flexure (and hence within reach of a 60 cm flexible sigmoidoscope) only 42 per cent were detected pre-operatively: the remaining tumours were noted at surgery (24 per cent) or found incidentally on pathological examination of the resected specimen (34 per cent). Histological examination of these synchronous lesions revealed a high proportion with favourable stage (Dukes' A — 75 per cent) and grade (well or moderate differentiation - 90 per cent). Over the same 16-year period, 10 patients presented with an ‘early’ metachronous lesion (<3 years from initial surgery). Review of these cases noted negative findings on the initial barium studies in four patients and a failure to conduct full examination of the colon at initial presentation in the remaining six. It is concluded that full examination of the colon in all patients presenting with primary colorectal cancer is mandatory and that, in the light of this experience and recent reports in the literature, this should be by pre- or peroperative colonoscopy.

We have performed a prospective study on 117 patients in order to assess the value of a single contrast water soluble enema in acute large bowel obstruction. In 99 cases where the plain films suggested a diagnosis of mechanical obstruction, the Diodone enema confirmed its presence in 52, and relocated its site in 11. There was free flow of contrast to the caecum in the remaining 35, 11 of whom were shown to have idiopathic pseudoobstruction. The plain films suggested a diagnosis of pseudo-obstruction in 18 patients. The Diodone enema confirmed this diagnosis in 15, but revealed an unsuspected mechanical obstruction in two. The examination failed in two cases. We conclude that the water soluble single contrast enema is of value in the management of large bowel obstruction. It will confirm the diagnosis of mechanical obstruction and prevent unnecessary surgery in patients with pseudo-obstruction.

We present our experience in 850 consecutive patients who had a laparotomy through a lateral paramedian incision during the period 1977–1981. These patients underwent both elective and emergency procedures covering a wide range of intra-abdominal conditions, and had a high incidence of factors known to predispose to wound dehiscence and incisional hernia formation. Follow-up in each case for at least 1 year revealed no wound dehiscences and 3 incisional hernias (0·37 per cent). We conclude that the lateral paramedian incision is inherently strong and that this strength is due to the splintage of the wound by the rectus abdominis muscle and the wide shutter mechanism that this provides.