Bowel dysfunction after elective spinal surgery: etiology, diagnostics and management based on the medical literature and experience in a university hospital.

BACKGROUND: Bowel dysfunction after spinal surgery is often underestimated and if not treated in a timely manner can lead to undesirable surgical interventions or fatal complications. The current medical literature primarily focuses on bowel dysfunction as a result of spinal injury. OBJECTIVE: The purpose of this review is to explore this topic in evaluating current evidence regarding the causes of acute bowel dysfunction after elective spinal surgery, primarily the thoracolumbar spine. Since available evidence for recommendations of treatment is scarce, an interdisciplinary management approach for treatment of bowel dysfunction following spinal surgery is also formulated. MATERIAL AND METHODS: An extensive literature search was carried out on PubMed. Keywords that were used in the search included bowel dysfunction, obstruction, postoperative ileus, spinal surgery, spinal fusion, constipation, opioid-induced constipation, colonic pseudo-obstruction, ischemic colitis, immobility-induced bowel changes, epidural anesthesia and diet. Relevant studies were chosen and included in the review. The treatment approach used in the spine center of a university hospital was included. RESULTS: Current research mainly focuses on investigating the nature and symptomatology of chronic bowel dysfunction after spinal cord injury. Emphasis on the acute phase of bowel dysfunction in patients after elective spinal surgery is lacking. The comorbidities that exacerbate bowel dysfunction postoperatively are well-defined. There has been refinement and expansion of the pharmacological and nonpharmacological treatment that could be implemented. Enough evidence exists to provide sufficient care. CONCLUSION: Management of acute bowel dysfunction after spinal surgery requires a comprehensive and individualized approach, encompassing comorbidities, behavioral changes, medications and surgery. Close supervision and timely treatment could minimize further complications. Research is required to identify patients who are at a higher risk of developing bowel dysfunction after specific spinal procedures.

Bacterial load of conditioned pressure ulcers is not a predictor for early flap failure in spinal cord injury.

OBJECTIVES: Pressure ulcers impose a major lifetime medical problem to patients with high-grade spinal cord injury (SCI). For patients with stages 3-4 pressure ulcers, plastic surgery is often the only remaining treatment option. Despite considerable flap failure rates of around 30%, only sparse knowledge exists on predictors for flap failure. Hence, identification of predictors for flap failures is needed. METHODS: We prospectively enrolled 38 SCI patients with stages 3-4 pressure ulcers scheduled for plastic surgery. Preoperative wound swabs, intraoperative tissue samples and postoperative drainage liquids were microbiologically analyzed. In multivariable logistic regression analyses, bacterial loads of deep tissue cultures of intraoperative samples as well as other clinical variables were analyzed with respect to the prediction of flap failures. RESULTS: The flap failure rate was 27.5%. Bacterial loads of deep tissue cultures were not predictive for flap failure, neither was the colonization with a specific bacterial strain. We observed a considerable fluctuation of microbiological environment from initial swab cultures, intraoperative samples and postoperative drainage fluids. Antibioprophylaxis was sufficient in only 75% of deep tissue cultures and 69% of drainage fluids. Insufficient antibioprophylaxis was associated with a higher flap failure rates (odds ratio 6.3, confidence interval 1.2-41.0). CONCLUSION: After inpatient wound conditioning, bacterial load analysis of intraoperative wound tissue cultures is ineffective in order to predict flap failure rates in SCI patients with stages 3-4 pressure ulcers after flap surgery. Instead, insufficient antibioprophylaxis might be a factor contributing to flap failure.

Spinal cord injury: association with axonal peripheral neuropathy in severely paralysed limbs.

BACKGROUND AND PURPOSE: Pressure sores are a major health problem in spinal cord injury (SCI). In this population pressure damage to peripheral nerves was not thoroughly investigated so far. However, intact peripheral nerves and innervated muscles are a prerequisite for the effectiveness of supportive therapies like functional electrical stimulation (FES). METHODS: We assessed electroneurographic (ENG) data of lower limbs in SCI individuals admitted to our hospital due to severe pressure sores. Our centers prospectively acquired ENG data of the European Multicenter study about SCI (EMSCI) patients served as early control. RESULTS: In the pressure sore cohort (n = 15) all patients were sensory-motor complete (American Spinal Cord Injury Association Impairment Scale A). Most patients (10/15) suffered from a severe axonal sensory-motor polyneuropathy in paralysed legs with absent compound muscle action potentials (CMAPs) of tibial/peroneal nerves as well as absent sensory nerve action potentials of sural nerves. The onset of this polyneuropathy dates within the first year after incident SCI and was mainly associated with increasing sensory-motor completeness as demonstrated by a significant CMAP drop of our centers EMSCI-ENG data on serial tibial nerve recordings in 275 patients. CONCLUSIONS: Severe SCI is associated with an early-onset axonal polyneuropathy in paralysed limbs to which pressure damage might contribute. Because intact peripheral nerves are required for: (i) maintenance of motor function in centrally impaired muscles; and (ii) effectiveness of supportive therapies like FES, ENG-monitoring could serve as a low invasive screening method for peripheral nerve integrity in patients with SCI to initiate pressure relief procedures early enough.

Linkage of body mass index to chromosome 20 in Utah pedigrees.

Several linkage studies have hinted at the existence of an obesity predisposition locus on chromosome 20, but none of these studies has produced conclusive results. Therefore, we analyzed 48 genetic markers on chromosome 20 for linkage to severe obesity (BMI> or =35) in 103 extended Utah pedigrees (1,711 individuals), all of which had strong aggregation of severe obesity. A simple dominant model produced a maximum multipoint heterogeneity LOD score of 3.5 at D20S438 (55.1 cM). Two additional analyses were performed. First, a one-gene, two-mutation model (with one dominant mutation and one recessive mutation) increased the LOD score to 4.2. Second, a two-locus model (with one locus dominant and one recessive) generated a multipoint LOD score of 4.9. We conclude that one or more severe obesity predisposing genes lie within an interval of approx. 10 cM on chromosome 20. This study generated significant LOD scores which confirm suggestive linkage reports from previous studies. In addition, our analyses suggest that the predisposing gene(s) is localized very near the chromosome 20 centromere.

Genotoxicity tests for new chemicals in Germany: routine in vitro test systems.

According to regulations in the European Union, new chemical substances must be notified before they can be introduced onto the market. One of the prerequisites for notification is that toxicological properties, including mutagenicity, are examined. In this paper, a report on routine in vitro mutagenicity testing is given for 776 new substances notified in Germany between 1982 and 1997. In general, the methodological quality of testing was in line with internationally accepted guidelines. Bacterial gene mutation tests (Bact) were conducted for nearly all of the substances, 13.4% were positive. Of the Bact-positive substances, 36 were also tested in the in vitro chromosomal aberration test (CAbvit) and the mammalian cell gene mutation test (MCGM). Twenty-six of these (72. 2%) were negative in both mammalian cell tests indicating that the genotoxic potentials of the substances are not relevant for man. Of all new substances, 333 were tested in CAbvit, here the percentage of positive findings was 25.2%. More than 80% of the in vitro clastogens were negative in the Bact. With respect to a sensitive detection of genotoxic potentials of substances, the combination 'Bact+CAbvit' is appropriate for basic testing. In our database CHL cells were more sensitive to clastogenic effects than other cell types. Only very few clastogens were identified as 'high toxicity clastogens'. MCGM tests were performed for 118 substances, quite often as follow-up in case of positive Bact tests. In total, 12.7% of the substances were positive in the MCGM. However, there was a clear difference in the frequencies of positive findings in HPRT tests (5.5%) and mouse lymphoma assays (MLA; 37.0%). None of the MCGM-positive substances was a 'unique positive', i.e., negative in Bact and CAbvit.

An 80 Kb P1 clone from chromosome 3p21.3 suppresses tumor growth in vivo.

High frequencies of allelic loss on the short arm of chromosome 3 in small cell lung cancer (SCLC) and a number of other tumors suggest the existence of a tumor suppressor gene(s) within the deleted regions. Two small cell lung cancer lines, NCI H740 and GLC20, have been described which have homozygous deletions in the region 3p21.3. The deleted region overlaps with a 2 Mb fragment of human DNA present in the interspecies hybrid HA(3)BB9F, that suppresses tumor formation by mouse A9 fibrosarcoma cells. Human sequences from this cell hybrid were isolated using inter Alu PCR. From this starting point, a P1 contig was developed for the region of 450 Kb that is common to the homozygous deletions seen in the SCLC lines NCI H740 and GLC20 and is also present in HA(3)BB9F, the suppressed A9 hybrid. Individual P1 clones were assayed for their ability to suppress the tumorigenicity of the mouse fibrosarcoma cell line A9 as assayed by injection of transfected A9 cells into athymic nude mice. The introduction of one of the P1 clones into A9 cells resulted in suppression of tumor growth whereas two other P1 clones from the contig failed to suppress tumor formation in athymic nude mice. These data functionally delimit a tumor suppressor locus to a region of 80 kb within a P1 clone at 3p21.3.

Isolation of the human semaphorin III/F gene (SEMA3F) at chromosome 3p21, a region deleted in lung cancer.

Small cell lung cancer (SCLC) has been correlated with a deletion in the short arm of chromosome 3, with the region 3p21 being lost from one homolog in almost all cases. Two SCLC cell lines have homozygous deletions in 3p21, and these deletions overlap with a fragment of chromosome 3 that has tumor suppression activity in vivo. We have isolated some cDNA clones from this region that are homologous to the genes constituting the semaphorin family. They represent a novel human semaphorin, termed sema III/F (HGMW-approved symbol SEMA3F), which is expressed as a 3.8-kb transcript in a variety of cell lines and tissues; it is detected as early as Embryonic Day 10 in mouse development. There is high expression in mammary gland, kidney, fetal brain, and lung and lower expression in heart and liver. Although there is reduced expression of this gene in several SCLC lines, no mutations were found. This semaphorin homolog has characteristics of a secreted member of the semaphorin III family, with 52% identity with mouse semaphorin E and 49% identity with chicken collapsin/semaphorin D.

Novel germline mutation of the p53 tumor suppressor gene in a child with incidentally discovered adrenal cortical carcinoma.

PURPOSE: We report a case of adrenal cortical carcinoma in an infant, which was incidentally discovered by renal sonography after a urinary tract infection. The previous death of a sibling after rhabdomyosarcoma in infancy prompted a search for a heritable p53 tumor suppressor gene mutation in this family. PATIENTS AND METHODS: Starting with frozen adrenal carcinoma tissue, polymerase chain reaction (PCR) amplification followed by direct sequencing of exons 4-8 of p53 was used to search for a mutation. When a mutation was identified in exon 6 of the tumor p53 sequence, PCR amplification and direct sequencing of exon 6 alone was then performed on DNA from peripheral blood lymphocytes (PBLs) of all immediate family members to determine whether a germline mutation was present. A different set of primers was used by a second laboratory at our institution to independently confirm the presence of the mutation in the adrenal carcinoma and in paraffin-embedded rhabdomyosarcoma tissue of the deceased sibling. RESULTS: A C-to-T transition was identified at a CpG site in codon 196 resulting in a change from arginine to a stop codon (CGA to TGA). The identical mutation, present as the sole p53 allele in the tumor DNA samples and in the heterozygous state with wild type p53 allele in DNA from PBLs (germline), was found in the adrenal carcinoma, the rhabdomyosarcoma, and the PBLs of the tumor-bearing child and her healthy father and 5-year-old brother. This nonsense mutation of p53 has never before been reported in the germline. The extended pedigree showed only one known additional cancer. CONCLUSIONS: A novel germline p53 mutation was identified by investigation of a sibling pair with cancers associated with the Li-Fraumeni syndrome in a family with an otherwise negative history for cancer. The implications of this case for identification of carriers of p53 germline mutations and their clinical management are discussed.

p53 mutations in gastric and colorectal cancers in Texas Hispanics versus Anglos.

Gastric cancer is more than twice as common in Hispanics as in Anglos in Texas, while colorectal cancer is almost twice as common in Anglos as Hispanics. To test the hypothesis that mutations in the p53 tumour suppressor gene are involved in these differences, we examined 131 gastric and 138 colorectal cancers from Hispanic and Anglo patients from South Texas and Mexico using immunohistochemistry (IHC) as a screening assay for p53 mutations. The fraction of p53 positive cases was not significantly different in gastric cancers from Hispanics compared to Anglos (43% versus 61%, respectively, p = 0.13) or in colorectal cancer (57% versus 58%, respectively, p = 1.0), suggesting that p53 mutations are not involved in causing the different incidences of these cancers in these populations. In addition, the types of p53 mutations arising in gastric tumours from Hispanic patients were consistent with those reported in gastric tumours in other populations. Sequencing of mutations in five gastric cancers revealed two G:C to A:T transitions, two A:T to G:C transitions and one complex deletion. In contrast with findings in studies in other tumour types, neither stage nor survival was associated with p53 positive staining by IHC in either gastric or colorectal tumours in this study. Positive p53 immunostaining was associated with the diffuse histological subtype in gastric carcinoma (p = 0.05) and high histological grade in colorectal carcinoma (p = 0.04).

A homozygous deletion on chromosome 3 in a small cell lung cancer cell line correlates with a region of tumor suppressor activity.

Small cell lung cancer (SCLC) tumors frequently display deletions on the short arm of chromosome 3 suggesting the existence of a 'tumor suppressor' gene within that region whose functional inactivation may be involved in tumorigenesis. Recently, a hybrid, HA(3)BB9F, was identified that contains a small fragment of human chromosome 3 of approximately 2 Mb on a mouse (A9) background (Killary et. al., 1992). This hybrid was utilized to define a functional tumor suppressor gene within 3p22-p21 which could suppress the tumorigenic properties of the mouse fibrosarcoma cell line. The existence of a tumor suppressor gene in the region 3p22-p21 is supported by the present report which describes the assessment of 89 SCLC and 32 non-SCLC lung cancer tumors and cell lines for the existence of a homozygous deletion(s) at 43 loci on the short arm of chromosome 3. One of the SCLC cell lines was found to harbor a homozygous deletion involving the loss of five markers on chromosome 3p. All five of the markers map to the region 3p21.3-p21.2 and four of the five markers are located within the chromosome 3 fragment exhibiting properties of tumor suppression in the HA(3)BB9F hybrid. The other tumors analysed all retained at least one copy of each of the markers assessed.

Serum luteinizing hormone, prolactin, and thyrotropin and their pituitary subunit mRNA levels during proestrus in the Syrian hamster.

mRNA levels for alpha, luteinizing hormone beta (LH beta), and prolactin (Prl) were examined during the hamster estrous cycle, with sampling most frequent (1-hour intervals) on the afternoon of proestrus. These transcripts encode the peptide subunits for the pituitary hormones LH and Prl which are necessary for reproductive function. Serum hormone levels of LH and Prl, analyzed by 24-hour periodic regression, exhibited a 24-hour periodicity on proestrus characterized by a large surge peaking at about 18.00 h. Combining the data for non-proestrous days of the cycle disclosed a rhythm with similar timing for LH and Prl. Thyroid-stimulating hormone (TSH) and TSH beta RNA profiles during hamster proestrus are reported for the first time. Serum TSH exhibited a pronounced peak coincident with that of the other hormones on proestrus. Because of variations at other times on the day of proestrus, however, a 24-hour periodicity was not manifested by regressional analysis. Combined non-proestrous serum TSH data also revealed no consistently timed regressional 24-hour periodicity. During proestrus, pituitary mRNA values for alpha, LH beta, and Prl simultaneously exhibited a rise from the lowest to the highest of all proestrous values in the 3-5 h prior to the time of the pre-ovulatory peak of circulating hormone concentrations. RNA for TSH beta exhibited an earlier, broader peak on proestrus. Periodic regression indicated a significant 24-hour rhythm for alpha mRNA in data pooled from non-proestrous days (acrophase 05.00 h) and for TSH beta mRNA on proestrus (acrophase 04.54 h).(ABSTRACT TRUNCATED AT 250 WORDS)

Use of the single strand conformation polymorphism technique and PCR to detect p53 gene mutations in small cell lung cancer.

Recent studies have suggested that the p53 oncoprotein might function normally as a tumor suppressor. Mutations in highly conserved regions of the p53 gene have been observed in numerous types of tumors and tumor cell lines. To detect in a more sensitive manner p53 gene mutations in small cell lung cancer (SCLC) we utilized the single strand conformation polymorphism (SSCP) technique of Orita et al., (1989). Using PCR primers for the most highly conserved regions of the p53 gene, including exons 4-9, we have identified p53 mutations in 5 of 9 small cell lung cancer (SCLC) tumor DNA samples and in 1 SCLC cell line. None of the mutations seen in tumor DNA samples were present in normal DNA from the same patients, indicating that mutation of the p53 gene in these tumors was a somatic event. Of the six mutations observed, two were found in exon 7, three were found in the region encompassing exons 8 and 9, and one was found in the region encompassing exons 5 and 6. Nucleotide sequencing of one of the exon 7 mutations and one of the exon 8-9 mutations indicated that each was a C to T transition. In SCLC-6 the mutation resulted in substitution of serine for proline at amino acid 278 and in SCLC-4 substitution of tryptophan for arginine at amino acid 248, both nonconservative amino acid substitutions. Both of these changes are in regions of the p53 gene where mutations have been observed in other tumors. Two additional mutations were observed in SCLC cell lines using conventional PCR techniques. One of these is a mutation which results in altered splicing of the p53 pre-mRNA.

Altered structure and expression of the human retinoblastoma susceptibility gene in small cell lung cancer.

Karyotypic and molecular genetic evidence has indicated that deletion or rearrangement of both chromosomes 3 and 13 may be important in the pathology of human small cell lung cancer (SCLC). The retinoblastoma susceptibility gene, RB, on chromosome 13 band q14, has previously been shown to be altered in SCLC [J. W. Harbour et al., Science (Wash. DC), 241: 353-357, 1988; J. Yokota et al., Oncogene, 3: 471-475, 1988]. Our studies of 26 SCLC tumor and normal DNA samples indicate that 6 of 6 patients whose normal cell DNA was heterozygous for an RB restriction fragment length polymorphism have lost one of the two alleles in their tumor DNA. Consistent with other studies, we find 2 of 26 tumors with homozygous deletions within the RB gene. Of 13 SCLC cell lines examined, only 3 expressed greater than trace amounts of RB mRNA. RB protein was detected in 2 of 14 SCLC cell lines examined, unlike the results of Yokota et al. (Oncogene, 3: 471-475, 1988) which showed no RB protein in any of the 9 cell lines they examined. Only unphosphorylated RB protein was detected in SCLC cell line H209, suggesting that the RB protein may be inactivated by a novel mechanism in this cell line. These data suggest that inactivation of the RB gene is a frequent if not universal event in SCLC.

Effects of alterations in the leader sequence of Rous sarcoma virus RNA on initiation of translation.

The 372-nucleotide leader sequence of Rous sarcoma virus RNA contains three conserved short open reading frames and other sequences responsible for a variety of life cycle functions. We have investigated several aspects of the leader RNA which may influence the translation of the major coding regions to which the leader is juxtaposed. We found that small perturbations of the leader length do not affect the binding and scanning of ribosomal subunits by more than about 10%, that the length and/or structure of the RSV RNA leader is near optimal for translation of the major coding regions of the viral RNA, that inclusion or deletion of open reading frames influences downstream initiation in a manner that is not strictly additive, and that reinitiation of translation at the gag gene is very efficient.

The DNF15S2 locus at 3p21 is transcribed in normal lung and small cell lung cancer.

Small cell lung cancer (SCLC) has been associated with a deletion of the short arm of chromosome 3. One SCLC cell line, H748, has an interstitial deletion of chromosome 3p and shows allele loss for the DNF15S2 locus detected by the probe lambda H3. Conservation of DNF15S2 sequences in mouse indicated that this human genomic fragment may contain coding sequences. Screening of a normal lung cDNA library with chromosome 3-specific fragments of the lambda H3 probe resulted in the isolation of 18 positive clones. The cDNA clones detect an additional DNA polymorphism that is in linkage disequilibrium with the HindIII polymorphism of the DNF15S2 locus. Sequence analysis indicated that the DNF15S2 locus could potentially code for a previously unreported protein of 67 kDa which has 26 cysteine residues. DNF15S2 is part of the coding region of a 3.3-kb mRNA expressed in lung. Northern analysis indicated that this mRNA was not detectable in one of five SCLC lines. This SCLC line, H128, also lacks the enzyme aminoacylase 1.

Synthesis in vitro of a seven amino acid peptide encoded in the leader RNA of Rous sarcoma virus.

Sequences of avian retroviral RNAs suggest that short open reading frames in the putatively untranslated leader sequences might direct the synthesis of small peptides. Previous analyses indicate that translation of Rous sarcoma virus (RSV) RNA in vitro faithfully reflects translation of the viral RNA in the chick cell. Accordingly, we sought to determine if the heptapeptide LP1, encoded in the open reading frame closest to the 5' end of RSV RNA, could be synthesized in vitro since this would strongly suggest that it might also be synthesized in vivo. Here we confirm that RSV RNA directs the synthesis of LP1 in rabbit reticulocyte lysates. LP1 is rapidly degraded in the lysate by an aminopeptidase activity. On the basis of the following observations, we propose that the open reading frame encoding LP1 plays a role in the life cycle of avian retroviruses. The LP1 open reading frame is ubiquitous with respect to position and length in 12 strains of avian retrovirus. In the amino acid sequences of the 12 strains, only three of the seven residues are invariant. On the basis of the conservation of the -3 and +4 nucleotides flanking the AUG codon, the strengths of initiation for translation of LP1 are approximately the same in the different viruses. The LP1 open reading frame is positioned in front of sites on retrovirus RNA that are required for initiation of cDNA synthesis and for packaging of the RNA into mature virus.

Identification of a ribosome-binding site for a leader peptide encoded by Rous sarcoma virus RNA.

A new method for identifying ribosome-binding sites was developed to determine whether AUG codons in the 5'-terminal RNA sequence of Rous sarcoma virus were used to initiate protein synthesis. We found that when translation is inhibited, the major ribosome-binding site on Rous sarcoma virus RNA is at the 5'-proximal AUG codon, even though the primary translational product from this RNA, Pr76gag, is encoded behind the fourth AUG codon 331 bases downstream from the observed initiation site. These results suggest that ribosomes can initiate translation on Rous sarcoma virus RNA at more than one site, thereby producing a seven-amino-acid peptide, as well as the gag gene polyprotein precursor of Mr 76,000.

Vibration effects on three measures of relaxation.

The effect of vibrotactile stimulation on relaxation as measured by EMG recording of the frontalis and trapezius muscles and by subjective report was assessed. It was predicted that low-frequency vibrotactile stimulation (less than 70 Hz) would facilitate muscle relaxation when measured by both EMG frontalis and trapezius recordings and by subjective report. The participants (8 male and 8 female) were randomly assigned to split-plot, before/after design consisting of four between-subjects treatments and one within-subjects treatment (pre- and post-treatment). The between-subjects treatments were footrest vibration, backrest vibration, footrest-backrest vibration combined, and control. The within-subjects treatment included pre- and post-treatment levels. Results of repeated-measures analyses of variance on each set of data yielded a significant change from pre- to posttreatment condition on all EMG and subjective report measures of muscle tension except the control. The utility of using EMG as a measure of relaxation is discussed.