Attendance at a pain clinic with severe chronic pain after open and laparoscopic inguinal hernia repairs

BACKGROUND

The aim was to compare the frequency of severe chronic pain that required attendance at a pain clinic after open and laparoscopic inguinal hernia repairs.

METHODS

This was a retrospective analysis of 7999 patients who underwent inguinal hernia repair between January 1994 and December 2001. The definition of severe chronic pain was pain related to inguinal hernia surgery that was bad enough for the patient to seek further medical help and be referred to the specialist pain clinic after exclusion of surgically correctable pathology such as hernia recurrence.

RESULTS

During the study there were 7153 open repairs and 846 laparoscopic repairs. Sixty-nine patients (1.0 per cent) were referred to the pain clinic a median of 16.9 (range 5.1-69.4) months after open hernia repair. Three patients (0.4 per cent) were referred a median of 16.5 (range 7.3-21.5) months after laparoscopic hernia repair (P = 0.045).

CONCLUSION

Laparoscopic inguinal hernia repair was associated with a significantly lower frequency of attendance at the pain clinic with severe chronic pain.

Cyclo-oxygenase-2 expression in Barrett's oesophageal carcinogenesis: an immunohistochemical study

BACKGROUND

The incidence of Barrett's oesophageal adenocarcinoma is increasing more rapidly than any other malignancy in industrialized countries. Cyclo-oxygenase-2 appears to play an important role in gastrointestinal carcinogenesis. Previous studies on cyclo-oxygenase-2 expression in Barrett's oesophageal carcinogenesis have utilized tissue samples obtained from different patients. We sought a definitive comparison of cyclo-oxygenase-2 expression in the sequence of Barrett's metaplasia-dysplasia-adenocarcinoma within the same patients.

METHODS

Paraffin-embedded oesophago-gastrectomy specimens from 20 patients, containing successive stages of Barrett's metaplasia, high-grade dysplasia and adenocarcinoma, were analysed for cyclo-oxygenase-2 expression by immunohistochemistry.

RESULTS

Cyclo-oxygenase-2 was constitutively expressed in the basal layers of cells in the adjacent normal squamous oesophageal epithelium, but a higher cyclo-oxygenase-2 expression was observed in Barrett's metaplasia. A further increase in cyclo-oxygenase-2 expression was detected in high-grade dysplasia, but cyclo-oxygenase-2 was decreased in adenocarcinoma tissue, regardless of its stage or level of differentiation.

CONCLUSIONS

Cyclo-oxygenase-2 expression is progressively increased when squamous oesophageal epithelium develops into Barrett's metaplastic epithelium and then into high-grade dysplasia, but appears to decrease when adenocarcinoma develops. These findings may be significant for an effective chemo-prevention strategy with selective cyclo-oxygenase-2 inhibitors.

Prospective randomized trial of laparoscopic Nissen fundoplication versus maintenance proton pump inhibition in the treatment of gastro-oesophageal reflux disease in patients aged under 65 years: preliminary results

Background

Laparoscopic Nissen fundoplication (LNF) was compared with maintenance proton pump inhibition (PPI) in patients with gastro-oesophageal reflux disease (GORD).

Methods

Some 113 patients (60 men; median age 45 (range 25–64) years) presented between June 1997 and June 1998 with a history of GORD of at least 2 years' duration. After giving informed consent they were investigated by endoscopy, 24-h pH and oesophageal manometry. Of 66 patients who completed the investigations, 57 had significant GORD; these were randomized, 29 to PPI and 28 to LNF.

Results

Endoscopic findings were equivalent in the two groups: 75 per cent of the PPI group had a hiatus hernia compared with 78 per cent of the LNF group; 54 per cent of the PPI group had oesophagitis compared with 71 per cent in the LNF group. Twenty-four-hour pH monitoring revealed De Meester scores of 21 (range 7–92) in the PPI group compared with 20 (range 10–99) in the LNF group. Manometry revealed a median␣lower oesophageal sphincter pressure (LOSP) of 10 (range 0–30) mmHg in the PPI group compared with 7 (range 1–30) mmHg in the LNF group. At 3 months after start of therapy, 24-h pH monitoring revealed a median De Meester score of 11 for both groups (PPI range 7–24, LNF range 9–39). Median LOSP was 15 mmHg in the PPI group compared with 17 mmHg in the LNF group.

Conclusion

Preliminary results suggest that LNF provides the same reduction in acid reflux as maintenance PPI in the short term. Further study of this group of patients will assess not only the physiological benefits of surgery versus maintenance PPI but also its impact on well being and relative costs of the two treatments.

Review of laparoscopic urology

Laparoscopy in urology has been slow to develop in the United Kingdom. Much of the pioneering work has been done in America and continental Europe. It is gradually gaining in popularity as urologists and the general public become more aware of the advantages it offers in terms of patient morbidity and surgical results. The aim of this review is to summarize the development of laparoscopic urology to date and to examine the various indications and the benefits of its application.

Laparoscopic distal pancreatectomy. Three cases of insulinoma

BACKGROUND

Surgery for benign pancreatic disease has traditionally required a major laparotomy however the minimal-access approach is now being applied to a wide variety of procedures, and surgery of the pancreas need not be excluded.

METHODS

Laparoscopic distal pancreatectomy was performed on three patients presenting with insulinomas found on preoperative investigation to lie within the tail of the pancreas.

RESULTS

All three patients had an excellent clinical outcome and returned to a state of normoglycemia. All of them made a rapid recovery with no major complications.

CONCLUSION

Laparoscopic distal pancreatectomy is a viable technique for removing insulinoma of the tail of the pancreas.

High resolution emission spectra of TL materials

High resolution emission spectra of several TL materials, that are commonly used in dosimetry, were measured using a low cost fibre optic spectrometer containing a 2048 pixel CCD array. The spectra were taken from 177 to 890 nm with a wavelength resolution of 1.3 nm. This allowed for line width discrimination and the resolution of transitions that have not been seen so far. For rare earth doped materials like CaF2:Tm (TLD-300) and CaF2:Dy (TLD-200) the spectral lines were compared to the energy levels measured by Dieke and Crosswhite leading to the identification of most of the transition lines.

Elimination of fecal coliforms and F-specific RNA coliphage from oysters (Crassostrea virginica) relaid in floating containers

Declining oyster (Crassostrea virginica) production in the Chesapeake Bay has stimulated aquaculture based on floats for off-bottom culture. While advantages of off-bottom culture are significant, the increased use of floating containers raises public health and microbiological concerns, because oysters in floats may be more susceptible to fecal contamination from storm runoff compared to those cultured on-bottom. We conducted four commercial-scale studies with market-size oysters naturally contaminated with fecal coliforms (FC) and a candidate viral indicator, F-specific RNA (FRNA) coliphage. To facilitate sampling and to test for location effects, 12 replicate subsamples, each consisting of 15 to 20 randomly selected oysters in plastic mesh bags, were placed at four characteristic locations within a 0.6- by 3.0-m "Taylor" float, and the remaining oysters were added to a depth not exceeding 15.2 cm. The float containing approximately 3,000 oysters was relaid in the York River, Virginia, for 14 days. During relay, increases in shellfish FC densities followed rain events such that final mean levels exceeded initial levels or did not meet an arbitrary product end point of 50 FC/100 ml. FRNA coliphage densities decreased to undetectable levels within 14 days (16 to 28 degrees C) in all but the last experiment, when temperatures fell between 12 and 16 degrees C. Friedman (nonparametric analysis of variance) tests performed on FC/Escherichia coli and FRNA densities indicated no differences in counts as a function of location within the float. The public health consequences of these observations are discussed, and future research and educational needs are identified.

Competitive displacement of pT alpha by TCR-alpha during TCR assembly prevents surface coexpression of pre-TCR and alpha beta TCR

During alphabeta T cell development, CD4(-)CD8(-) thymocytes first express pre-TCR (pTalpha/TCR-beta) before their differentiation to the CD4(+)CD8(+) stage. Positive selection of self-tolerant T cells is then determined by the alphabeta TCR expressed on CD4(+)CD8(+) thymocytes. Conceivably, an overlap in surface expression of these two receptors would interfere with the delicate balance of thymic selection. Therefore, a mechanism ensuring the sequential expression of pre-TCR and TCR must function during thymocyte development. In support of this notion, we demonstrate that expression of TCR-alpha by immature thymocytes terminates the surface expression of pre-TCR. Our results reveal that expression of TCR-alpha precludes the formation of pTalpha/TCR-beta dimers within the endoplasmic reticulum, leading to the displacement of pre-TCR from the cell surface. These findings illustrate a novel posttranslational mechanism for the regulation of pre-TCR expression, which may ensure that alphabeta TCR expression on thymocytes undergoing selection is not compromised by the expression of pre-TCR.

Identification of a novel pre-TCR isoform in which the accessibility of the TCR beta subunit is determined by occupancy of the 'missing' V domain of pre-T alpha

We have identified a novel pre-TCR isoform that is structurally distinct from conventional pre-TCR complexes and whose TCR beta chains are inaccessible to anti-TCR beta antibodies. We term this pre-TCR isoform the MB (masked beta)-pre-TCR. Pre-T alpha (pT alpha) subunits of MB-pre-TCR complexes have a larger apparent mol. wt due to extensive modification with O:-linked carbohydrates; however, preventing addition of O-glycans does not restore antibody recognition of the TCR beta subunits of MB-pre-TCR complexes. Importantly, accessibility of TCR beta chains in MB-pre-TCR complexes is restored by filling in the 'missing' variable (V) domain of pT alpha with a V domain from TCR alpha. Moreover, the proportion of pre-TCR complexes in which the TCR beta subunits are accessible to anti-TCR beta antibody varies with the cellular context, suggesting that TCR beta accessibility is controlled by a trans-acting factor. The way in which this factor might control TCR beta accessibility as well as the physiologic relevance of TCR beta masking for pre-TCR function are discussed.

A genome-wide family-based linkage study of coeliac disease

The susceptibility to develop coeliac disease (CD) has a strong genetic component, which is not entirely explained by HLA associations. Two previous genome wide linkage studies have been performed to identify additional loci outside this region. These studies both used a sib-pair design and produced conflicting results. Our aim is to identify non-MHC genetic loci contributing to coeliac disease using a family based linkage study. We performed a genome wide search in 16 highly informative multiply affected pedigrees using 400 microsatellite markers with an average spacing of 10 cM. Linkage analysis was performed using lod score and model free methods. We identified two new potential susceptibility loci with lod scores of 1.9, at 10q23.1, and 16q23.3. Significant, but lower lod scores were found for 6q14 (1.2), 11p11 (1.5), and 19q13.4 (0.9), areas implicated in a previous genome wide study. Lod scores of 0.9 were obtained for both D78507, which lies 1 cM from the gammaT-cell receptor gene, and for D2S364, which lies 12 cM from the CTLA4 gene.

On the dynamics of TCR:CD3 complex cell surface expression and downmodulation

TCR downmodulation following ligation by MHC:peptide complexes is considered to be a pivotal event in T cell activation. Here, we analyzed the dynamics of TCR:CD3 cell surface expression on resting and antigen-activated T cells. We show that the TCR:CD3 complex is very stable and is rapidly internalized and recycled in resting T cells. Surprisingly, the internalization rate is not increased following TCR ligation by MHC:peptide complexes, despite significant TCR downmodulation, suggesting that constitutive internalization rather than ligation-induced downmodulation serves as the force that drives serial ligation. Furthermore, TCR downmodulation is mediated by the intracellular retention of ligated complexes and degradation by lysosomes and proteasomes. Thus, our data demonstrate that ligation induces TCR downmodulation by preventing recycling rather than inducing internalization.

Comparative genome sequence analysis of the Bpa/Str region in mouse and Man

The progress of human and mouse genome sequencing programs presages the possibility of systematic cross-species comparison of the two genomes as a powerful tool for gene and regulatory element identification. As the opportunities to perform comparative sequence analysis emerge, it is important to develop parameters for such analyses and to examine the outcomes of cross-species comparison. Our analysis used gene prediction and a database search of 430 kb of genomic sequence covering the Bpa/Str region of the mouse X chromosome, and 745 kb of genomic sequence from the homologous human X chromosome region. We identified 11 genes in mouse and 13 genes and two pseudogenes in human. In addition, we compared the mouse and human sequences using pairwise alignment and searches for evolutionary conserved regions (ECRs) exceeding a defined threshold of sequence identity. This approach aided the identification of at least four further putative conserved genes in the region. Comparative sequencing revealed that this region is a mosaic in evolutionary terms, with considerably more rearrangement between the two species than realized previously from comparative mapping studies. Surprisingly, this region showed an extremely high LINE and low SINE content, low G+C content, and yet a relatively high gene density, in contrast to the low gene density usually associated with such regions.

K-ras mutations, rectal crypt cells proliferation, and meat consumption in patients with left-sided colorectal carcinoma

It has been suggested that N-nitroso compounds derived from meat may increase the risk of K-ras mutations in the human colon. We sought evidence of associations between red meat consumption, frequency and type of K-ras mutations in resected tumours, and the rate of crypt cell proliferation (CCP) in the normal mucosa of patients with left-sided colorectal carcinoma. Meat consumption was assessed by food frequency questionnaire, and CCP was determined in rectal biopsies obtained prior to surgery. K-ras mutations in the resected tumours were determined using a PCR-based oligonucleotide hybridization assay. Fifteen K-ras mutations were detected in tumours from 43 patients; 13/15 in codon 12, 3/15 in codon 13, and 1/15 in both codons 12 and 13. All mutations were G-->A or G-->T transitions. There was no statistically significant difference between intakes of red meat in patients with a K-ras mutation (92.4 +/- 9.7 g/day) and those without (82.3 +/- 7.7 g/day). Rectal CCP was significantly higher in patients than in healthy controls, but there was no correlation with meat consumption or K-ras mutation. These data do not support the hypothesis that meat consumption is a risk factor for acquisition of K-ras mutations during colorectal carcinogenesis.

Autosomal dominant spastic paraplegia: refined SPG8 locus and additional genetic heterogeneity

OBJECTIVE

To map the gene responsible for autosomal dominant pure hereditary spastic paraplegia (ADPHSP) in a large affected family.

BACKGROUND

Autosomal dominant pure hereditary spastic paraplegia (ADPHSP) is genetically heterogeneous, and loci have been mapped at chromosomes 2p (SPG4), 14q (SPG3), 15q (SPG6), and recently, in a single family, at chromosome 8q24 (SPG8).

METHODS

The authors carried out a genomewide linkage screen on a large family with ADPHSP, for which linkage to the chromosome 2, 14, and 15 loci was excluded.

RESULTS

Analysis of markers on chromosome 8q24 gave a peak two-point lod score of 4.49 at marker D8S1799. Analysis of recombination events in this family and in the previously published SPG8-linked family narrowed the SPG8 locus from 6.2 cM to a 3.4-cM region between markers D8S1804 and D8S1179. In another four families, linkage to all four known ADPHSP loci was excluded. The SPG8-linked family had a significantly older mean age at onset of symptoms and had significantly more wheelchair-using patients than the four linkage-excluded families.

CONCLUSIONS

These results contain the presence of an autosomal dominant pure hereditary spastic paraplegia (ADPHSP) locus at chromosome 8q24 and strongly suggest that there are at least five ADPHSP loci. The data provide additional evidence for locus-phenotype correlations in ADPHSP.

Randomized clinical trial of early laparoscopy in the management of acute non-specific abdominal pain

BACKGROUND

Abdominal pain of uncertain aetiology (non-specific abdominal pain; NSAP) is the commonest reason for emergency surgical admission. The aim of this study was to examine the role of early laparoscopy in the management of NSAP.

METHODS

Some 120 patients, admitted between November 1995 and October 1998 with acute abdominal pain of uncertain aetiology, were randomized into two groups: group 1 had laparoscopy during the first 18 h of admission and group 2 had close observation, conventional investigation and surgical intervention if signs of peritonism developed. Outcome measures were diagnosis, operative procedures, duration of hospital stay, readmission rate, morbidity and death, patient satisfaction and total number of investigations performed.

RESULTS

Median hospital stay was 2 (range 1-13) days in both groups (P = 0.87). A diagnosis was established in 48 (81 per cent) of 59 patients in group 1 compared with 22 (36 per cent) of 61 in group 2 (P < 0.0001). The morbidity rate was 14 (24 per cent) of 59 in group 1 and 19 (31 per cent) of 61 in group 2 (P = 0.3629). The readmission rate at a median follow-up of 21 (range 1-35) months was 17 (29 per cent) of 59 in group 1 compared with 20 (33 per cent) of 61 in group 2 (P = 0. 6375). Well-being scores improved from 134 on admission to 149 of 177 6 weeks later in group 1 (P = 0.007) and from 132 to 143 of 177 in group 2 (P = 0.089).

CONCLUSION

Early laparoscopy provided a higher diagnostic accuracy and improved quality of life in patients with NSAP.

Consumption of fish oil leads to prompt incorporation of eicosapentaenoic acid into colonic mucosa of patients prior to surgery for colorectal cancer, but has no detectable effect on epithelial cytokinetics

Fish oil (FO) was previously reported to partially normalize colorectal crypt cell cytokinetics in patients with colorectal neoplasms. We determined the effect of FO on the fatty acid composition of colonic mucosa and mesenteric adipose tissue and on rectal crypt cell proliferation in patients undergoing surgery for colonic carcinoma. Patients (49-28 males; 21 females) were randomly assigned to consume FO capsules (2 g b.d.; FO group) containing 1.4 g eicosapentaenoic acid (EPA) and 1.0 g docosahexaenoic acid per day, or safflower oil capsules (2 g b.d.; placebo group) for an average of 12.3 +/- 0.5 d prior to surgery. Rectal biopsies were obtained at entry, at surgery, and 8-12 wk postsurgery. Colonic biopsies and samples of mesenteric adipose tissue were analyzed for fatty acids by gas-liquid chromatography. Mitosis was determined in whole crypt mounts. The proportion of EPA (g/100 g total fatty acids) in mucosal lipids was significantly greater in FO patients compared to the placebo group, but there was no effect on mesenteric adipose tissue. However self-reported use of FO supplements prior to surgery was associated with higher levels of EPA in adipose tissue. There was no significant effect of FO on the frequency or spatial distribution of crypt cell mitosis. EPA from marine oil supplements is rapidly incorporated into the colonic mucosal lipids of humans, but the levels achieved in the present study did not modify colorectal cytokinetics.

Signals transduced by CD3epsilon, but not by surface pre-TCR complexes, are able to induce maturation of an early thymic lymphoma in vitro

Development of immature CD4-CD8- (double-negative) thymocytes to the CD4+CD8+ (double-positive) stage is linked to productive rearrangement of the TCRbeta locus by signals transduced through the pre-TCR. However, the mechanism whereby pre-TCR signaling is initiated remains unclear, in part due to the lack of an in vitro model system amenable to both biochemical and genetic analysis. In this study, we establish the thymic lymphoma Scid.adh as such a model system. Scid.adh responds to Ab engagement of surface IL-2Ra (TAC):CD3epsilon molecules (a signaling chimera that mimics pre-TCR signaling in vivo) by undergoing changes in gene expression observed following pre-TCR activation in normal thymocytes. These changes include down-regulation of CD25, recombinase-activating gene (RAG)-1, RAG-2, and pTalpha; and the up-regulation of TCRalpha germline transcripts. We term this complete set of changes in gene expression, in vitro maturation. Interestingly, Scid.adh undergoes only a subset of these changes in gene expression following Ab engagement of the pre-TCR. Our findings make two important points. First, because TAC:CD3epsilon stimulation of Scid.adh induces physiologically relevant changes in gene expression, Scid.adh is an excellent cellular system for investigating the molecular requirements for pre-TCR signaling. Second, Ab engagement of CD3epsilon signaling domains in isolation (TAC:CD3epsilon) promotes in vitro maturation of Scid.adh, whereas engagement of CD3epsilon molecules contained within the complete pre-TCR fails to do so. Our current working hypothesis is that CD3epsilon fails to promote in vitro maturation when in the context of an Ab-engaged pre-TCR because another pre-TCR subunit(s), possibly TCRzeta, qualitatively alters the CD3epsilon signal.

A new locus for autosomal dominant "pure" hereditary spastic paraplegia mapping to chromosome 12q13, and evidence for further genetic heterogeneity

Autosomal dominant pure hereditary spastic paraplegia (ADPHSP) is clinically characterized by slowly progressive lower-limb spasticity. The condition is genetically heterogeneous, and loci have been mapped at chromosomes 2p, 8q, 14q, and 15q. We have performed a genomewide linkage screen on a large family with ADPHSP, in which linkage to all four previously known loci was excluded. Analysis of markers on chromosome 12q gave a peak pairwise LOD score of 3.61 at D12S1691, allowing us to assign a new locus for ADPHSP (a locus that we have designated "SPG10") to this region. Haplotype construction and analysis of recombination events narrowed the SPG10 locus to a 9.2-cM region between markers D12S368 and D12S83. In addition, our data strongly suggest that there are at least six ADPHSP loci, since we describe a further family in which linkage to all five known ADPHSP loci has been excluded.