Agonists of the Ca(2+)-sensing receptor (CaR) activate nonselective cation channels in HEK293 cells stably transfected with the human CaR

Calcium (Ca2+) ions serve multiple roles both intra- and extracellularly. We recently cloned a cell surface, Cao(2+)-sensing receptor (CaR) that plays a central role in Cao2+ homeostasis by enabling direct regulation by Cao2+ of parathyroid hormone (PTH) secretion and the function of other tissues involved in mineral ion homeostasis. In parathyroid cells, the CaR activates phospholipase C, thereby raising the levels of inositol trisphosphate (IP3) and releasing Ca2+ from intracellular stores. High Cao2+ also activates Ca2+ influx into parathyroid cells through poorly defined mechanisms that may involve Ca(2+)-permeable, nonselective cation channels (NCC). We now show that human embryonic kidney (HEK293) cells also have NCC and, furthermore, that these channels are regulated by the CaR. We have utilized the cell-attached configuration of the patch clamp technique to characterize the properties of these channels as well as their regulation by various CaR agonists added to the external bath solution. The polycationic CaR agonist, neomycin (100 microM), as well as an elevated concentration of Cao2+ (3 mM), both of which activate the cloned CaR, significantly increased the probability of channel opening (Po) in HEK cells stably transfected with the CaR but not in nontransfected HEK cells which do not contain the receptor. Thus, the activation of the CaR enhances the activity of Ca(2+)-permeable NCC in these cells, which could contribute to the sustained increase in Cai2+ in parathyroid cells which is observed in response to elevated Cao2+. The CaR may also regulate the membrane functions of other CaR-expressing cells (e.g., those in the brain), at least in part, by modulating similar channels.

Effect of syringe size on bruising following subcutaneous heparin injection

BACKGROUND: Bruising and induration associated with subcutaneous heparin injection often result in sustained tenderness and severe ecchymosis at the injection site. Research-based practice guidelines for subcutaneous heparin administration are needed to reduce these adverse effects. OBJECTIVES: The purpose of this study was to investigate the effect of syringe size (1-mL vs 3-mL) on postinjection-site bruising and induration following the administration of subcutaneous heparin. METHODS: A convenience sample of 29 subjects receiving 5000 units of subcutaneous heparin at least twice a day was recruited from a large urban hospital. Subjects received their regularly scheduled subcutaneous heparin injections with a 3-mL or a 1-mL syringe in a randomized sequence using a standardized procedure. Injection sites were assessed for bruises and induration at 24, 48, and 72 hours after injection. RESULTS: The incidence of injection site bruising with 1- and 3-mL syringes was 79% and 69%, respectively. The use of a 3-mL vs 1-mL syringe resulted in significantly smaller bruises at 48 and 72 hours after injection. Induration at the injection site occurred in three patients. CONCLUSIONS: Findings suggest that 3-mL syringes are preferable to 1-mL syringes for heparin administration. The effect of other injection-related variables should be studied with the use of the 3-mL syringe, and tested on various populations.

Effect of syringe size on bruising following subcutaneous heparin injection

BACKGROUND

Bruising and induration associated with subcutaneous heparin injection often result in sustained tenderness and severe ecchymosis at the injection site. Research-based practice guidelines for subcutaneous heparin administration are needed to reduce these adverse effects.

OBJECTIVES

The purpose of this study was to investigate the effect of syringe size (1-mL vs 3-mL) on postinjection-site bruising and induration following the administration of subcutaneous heparin.

METHODS

A convenience sample of 29 subjects receiving 5000 units of subcutaneous heparin at least twice a day was recruited from a large urban hospital. Subjects received their regularly scheduled subcutaneous heparin injections with a 3-mL or a 1-mL syringe in a randomized sequence using a standardized procedure. Injection sites were assessed for bruises and induration at 24, 48, and 72 hours after injection.

RESULTS

The incidence of injection site bruising with 1- and 3-mL syringes was 79% and 69%, respectively. The use of a 3-mL vs 1-mL syringe resulted in significantly smaller bruises at 48 and 72 hours after injection. Induration at the injection site occurred in three patients.

CONCLUSIONS

Findings suggest that 3-mL syringes are preferable to 1-mL syringes for heparin administration. The effect of other injection-related variables should be studied with the use of the 3-mL syringe, and tested on various populations.

Escherichia coli tryptophanyl-tRNA synthetase mutants selected for tryptophan auxotrophy implicate the dimer interface in optimizing amino acid binding

Tryptophan auxotrophs of Escherichia coli in which mutations were mapped to the trpS locus (encoding tryptophanyl-tRNA synthetase) have been previously isolated. We have investigated the tryptophanyl-tRNA synthetase (TrpRS) purified from six auxotrophic strains for changes in amino acid activation and aminoacylation. Steady-state kinetic analyses show that these mutant TrpRS proteins have increases in the apparent KM for tryptophan, decreases in turnover number, or both, without significant changes in the apparent KM for ATP or tRNA(Trp). The crystal structure of a highly homologous tryptophanyl-tRNA synthetase from Bacillus stearothermophilus in a complex with the cognate aminoacyl adenylate allowed us to place the mutations in a structural context. The mutations in the enzymes are located in the KMSKS loop (M196I), in or near the active site (D112E, P129S, A133E) or far from the active site. The last three mutants (T60R, L91F, G329S) could not be predicted by examination of the protein structure as they line an interface between the C-terminal alpha-helix of one subunit and the Rossmann folds of both subunits, thus affecting a specific region of the dimer interface. These results support a role for dimerization in properly configuring the two active sites of the dimeric enzymes in the Trp/Tyr subclass of class I aminoacyl-tRNA synthetases in order to achieve optimal catalysis.

The effect of ambient temperature on the shoe-surface interface release coefficient

Previous studies of the shoe-surface interface correlated foot fixation with cleat length, configuration, and material composition as well as turf type and surface conditions. Our study examined the effect of temperature on the rotational torsion resistance of artificial turf football shoes. Five football shoe models, a flat-soled basketball-style turf shoe, a natural grass soccer-style shoe, and three multistudded turf shoes, were studied on dry Astro Turf at five temperatures (range, 52 degrees F to 110 degrees F). An assay device, a prosthetic foot mounted on a loaded stainless steel shaft, was used to determine the force necessary to release a shoe from the turf's surface. We used a torque wrench to apply a rotational force so that each shoe was pivoted counterclockwise through an arc of 60 degrees. Our results indicated that release coefficients differ within and among the shoe models at various turf temperatures. We also found that an increase in turf temperature, in combination with cleat characteristics, affects shoe-surface interface friction and potentially places the athlete's knee and ankle at risk of injury. Based on an established risk criterion, which correlated shoe-surface interface combinations in the laboratory with documented clinical occurrences, only the flat-soled basketball-style turf shoe could be designated "safe" or "probably safe" at all five temperatures.

Pharmacokinetics of pyropheophorbide-a-hexyl ether in the dog

BACKGROUND AND OBJECTIVES

Pyropheophorbide-a-hexyl ether (HPPH) is a new compound being investigated for use as a photosensitizer for photodynamic therapy; however, the pharmacokinetics are not known for any of the target species likely to be treated with this drug. The objective of this study was to determine the pharmacokinetic parameters of this drug prior to institution of a clinical trial in canine patients with various cancers.

STUDY DESIGN, MATERIALS AND METHODS

HPPH (0.3mg/kg i.v.) was administered to 12 dogs and blood samples were drawn at intervals for 24 hours and plasma HPPH concentrations were determined. Pharmacokinetic parameters were calculated for each dog.

RESULTS

No evidence of toxicity was noted in any dog. The mean half-life was calculated to be 26.98 +/- 2.35 hrs. The mean clearance was 5.061 +/- 0.214 ml/hr/kg. The mean volume of distribution of the central compartment was 0.069 +/- 0.003 L/kg, and the mean steady state volume of distribution was 4.47 +/- 0.25 L/kg.

CONCLUSION

The conclusion is that 0.3 mg/kg HPPH injected intravenously resulted in measurable plasma levels for 24 hrs, and resulted in no detectable adverse reactions.

Drugs, poverty, pregnancy, and foster care in Los Angeles, California, 1989 to 1991

To determine the characteristics and childbearing histories of women whose infants entered foster care in Los Angeles County, we examined the cases of 1,155 drug-using women whose infants were removed from them at birth and 236 non-drug-using women whose infants were also removed at birth by court order (July 1989 through March 1991). All of the women were indigent, and less than half had graduated from high school. The drug-using women frequently had criminal records, and more than a quarter were homeless. Many comparison women had mental health problems, and some (16.7%) were teenagers under court custody. Overall, 80% of all the children born to both groups of women were under court jurisdiction. Data obtained after study infants' births on 926 drug-using women observed for 18 months revealed that 22% had borne another infant who was placed in foster care; half of these infants had a positive drug immunoassay. Of the 185 non-drug-using women with 18-month follow-ups, 7.6% had borne another child who was in foster care. The magnitude of the repeated childbearing recorded among both groups of women in this study shows that preventive programs including family planning, mental health services, and drug prevention or rehabilitation programs have not reached this population.

Psychiatric consequences of radical curative surgery for gastric cancer

Radical resection of gastric cancer offers the best hope of cure, but carries the risk of significant psychological morbidity in addition to the well-documented physical complications. In the case presented, recognition of clinical depression after thoracoabdominal gastrectomy enabled successful psychological intervention.

Radical surgery for advanced and recurrent breast cancer

Locally advanced or recurrent breast cancer is commonly seen in breast clinics. One method of palliation for ulcerating tumours is a radical mastectomy with replacement of the chest wall defect with a myocutaneous flap. We report on our experience of this technique in the management of 35 women (21 advanced disease, 14 recurrent disease). The perioperative complications were minimal and there are some longterm survivors. 15 women are alive and well (range 20-96 months postoperatively, mean 55 months). This radical surgery, therefore, has a significant role in the management of selected women with breast cancer.

Determinants of birth weight in Vietnamese detainees in Hong Kong

Five hundred and fifty singleton pregnancies amongst Vietnamese Boat People delivering between January and December 1993 were studied post-natally. Multiple regression analysis showed no direct effect of ethnic origin on birth weight. When analyses were repeated on the two main ethnic subgroups we found that, amongst Anamese patients, both gestation at delivery and birth weight independently increased with longer duration of stay in Hong Kong. This relationship was not seen in Vietnamese patients of Chinese ethnic origin. Possible reasons for these different relationships are discussed.

Treatment of anal intraepithelial neoplasia

The natural history and malignant potential of anal intraepithelial neoplasia (AIN) remain uncertain, making management decisions about such lesions difficult. The management of 70 patients with AIN is described. The majority of lesions encountered were low grade (AIN I and II; 43 of 70) and required no treatment, but eight invasive anal cancers associated with high-grade AIN occurred over the 4-year study period. Three were a result of apparent progression of high-grade lesions; three more invasive lesions were found in areas of AIN III on histological examination. Surgical excision was used to treat 27 patients with AIN III. Treatment of extensive lesions involving the perianal and anal canal epithelium circumferentially in six patients involved excision of the whole of this epithelium and application of split skin grafts.

The effects of hypothermic and normothermic cardiopulmonary bypass on glyceryl trinitrate activity

Glyceryl trinitrate (GTN) is used to control arterial blood pressure during cardiopulmonary bypass (CPB) procedures, but its effects are often decreased during the period of extracorporeal support. The plasma and urine concentrations of GTN and glyceryl-1,2-dinitrate (1,2-GDN) and glyceryl-1,3-dinitrate (1,3-GDN) for male and female patients who received GTN during hypothermic CPB, and male and female patients who were given GTN during normothermic CPB, were measured by gas-liquid chromatography. During hypothermic CPB, the male and female subjects experienced significant decreases in GTN clearance (P < 0.05), 66% and 52%, respectively. Neither the males nor the females who underwent normothermic CPB experienced any significant change in GTN clearance. These results suggest that the lower core temperature during hypothermic CPB may decrease the biotransformation of GTN to GDNs and nitric oxide, thereby resulting in less dilation of blood vessels. Furthermore, the males in the hypothermic CPB group had significantly greater urinary concentrations of 1,3-GDN and 1,2-GDN than the females (P < 0.05), and the normothermic CPB males had a significantly greater urinary concentration of 1,2-GDN than the females in that group. The normothermic CPB males also had significantly higher plasma concentration of GTN at two time points, and 1,3-GDN at one time point, than the females. These data suggest that there may be a gender difference in GTN biotransformation.

Anal colposcopy and the diagnosis of anal intraepithelial neoplasia in high-risk gynecologic patients

The objective of this study was to define the colposcopic features of the normal anal canal and of anal human papillomavirus (HPV)-associated lesions, including anal intraepithelial neoplasia (AIN), and to correlate the colposcopic impression with the final histopathologic diagnosis. A controled colposcopic screening study of women considered at risk for HPV-associated anal epithelial abnormalities was carried out. All colposcopic assessments included a biopsy with matching histopathologic diagnosis. The study group consisted of 213 women who were considered at risk of anal HPV infection and AIN. A further group of 50 women, who had no previous history of ano-genital HPV infection or AIN and whose recent cervical smear was negative were recruited as controls. Informed consent was obtained from all patients, and the study was approved by the local ethical committee. In the control group of 50 women no AIN was detected. Normal histology was obtained in 45/50 (90%) biopsies where normality had been predicted on colposcopy. Histologic diagnosis in the at-risk group was normal in 143 (67%), subclinical papillomarvirus infection (SPI) in 24 (11%), and AIN of all grades (including three cases of early invasive squamous cancer in a field change of AIN III) in 46 (22%) patients. Nineteen of 24 (79%) cases of SPI were incorrectly predicted as normal on colposcopy, and another one (4%) as AIN I-II. Only four (17%) cases of SPI were correctly predicted at colposcopy. Of the 46 cases of histologically proven AIN, 26 (56%) were AIN I-II, and 20 (44%) were AIN III. Some 50% of AIN I-II were incorrectly predicted as SPI on colposcopy. Of the 20 AIN III lesions, 15 (75%) were correctly predicted by colposcopy. Three (20%) of these lesions contained foci of early invasion, of which in only one case (33.3%) was invasive disease suspected at colposcopy. Some 25% (5/20) of AIN III lesions were incorrectly diagnosed as AIN I-II at colposcopy. As is the experience with colposcopic assessment of the cervix, anal colposcopy predictions correlated well with the final histologic diagnosis, at the normal and high-grade AIN ends of the spectrum. The colposcopic predictive distinction between SPI and low-grade AIN (I-II) was less accurate. It was difficult to distinguish early invasive lesions within a field change of AIN III, from pure AIN III. In these studies there were three cases of early anal squamous carcinoma arising in AIN III lesions, two of which were unsuspected clinically.

Prevalence of anal human papillomavirus infection and intraepithelial neoplasia in renal allograft recipients

A study was performed to test the hypothesis that renal allograft recipients are at high risk of developing anal human papillomavirus (HPV) infection and anal intraepithelial neoplasia (AIN). A total of 133 renal allograft recipients and 145 control patients underwent anoscopy and biopsy. A polymerase chain reaction was used to detect HPV16 DNA in biopsy samples. A histological diagnosis of anal HPV infection or AIN was made in 32 allograft recipients (HPV infection, five; AIN I, 20; AIN II, three; AIN III, three; AIN III and anal cancer, one). One subject with AIN was detected in the control group. HPV16 DNA was detected in 47 and 12.4 per cent of anal biopsies in the allograft and control groups respectively. Renal allograft recipients are at high risk of developing anal HPV infection and neoplasia (P < 0.05). Further studies are required to determine whether screening anal examination is required in organ allograft recipients.

Anal human papillomavirus infection and squamous neoplasia in patients with invasive vulvar cancer

OBJECTIVE

To test the hypothesis that women with invasive vulvar cancer are at high risk of developing human papillomavirus (HPV)-associated anal squamous neoplasia.

METHODS

Forty women (median age 54.5 years; range 25-86) who were being treated or had been treated for invasive vulvar cancer and who had not had radiotherapy to the pelvis or anogenital region underwent anal microendoscopy and biopsy. A second group of 80 women who were similar in age to the study group and had no history of anogenital HPV infection or neoplasia formed the control group. The polymerase chain reaction was used to detect HPV 16 DNA in the vulvar and anal tissue samples from 33 patients in the study group and in the anal biopsies of all controls.

RESULTS

A histologic diagnosis of anal HPV infection or squamous neoplasia was made in 19 of 40 biopsies (47.5%) in the study group. These diagnoses consisted of one HPV, two anal squamous intraepithelial lesions (SIL) grade I, 15 and SIL grade III (four of which were associated with invasive anal cancers), and one invasive cancer in the absence of anal SIL. Human papillomavirus 16 DNA was detected in 16 of 33 (48.5%) of anal and 25 of 33 (75%) of vulvar biopsies. In addition, HPV 16 was detected in both the anal and vulvar samples in 13 of 16 cases (81%) of anal SIL III and invasive anal squamous cancer. No evidence of anal SIL was found in the controls, and HPV 16 DNA was identified in only 11 (13.7%) of the anal biopsies in this group.

CONCLUSIONS

This study provides further evidence for the etiologic relation between genital and anal squamous neoplasia. Furthermore, it shows that women with vulvar cancer are at high risk of having or developing HPV-associated anal neoplasia, particularly in younger patients (P = .0006; 95% confidence interval 12-34). Routine anal examination should be performed in patients with invasive vulvar cancer.

Surgery for gastric cancer

Radical dissection for gastric cancer is not widely practiced in the West. This paper reviews the evidence in support of lymphadenectomy and the techniques of radical resection as practiced by Japanese surgeons. We believe the published results support increased use of radical surgery in the treatment of gastric cancer and would recommend further adoption of this technique as there is minimal associated morbidity.

The dynamics of prostaglandin metabolism in human fetal membranes and decidua around the time of parturition

To address whether prostaglandins (PGs) produced in the amnion can gain access to the myometrium, we used three in vitro systems to determine the characteristics of PG secretion, metabolism, and transfer in amnion, chorion, and decidua around the time of parturition. PG metabolism, measured in explant cultures or cytosol preparations, occurs predominantly by the enzyme PG dehydrogenase, which was highest in chorion and was 2- to 3-fold more active for PGE2 than PGF2 alpha. The activity increased significantly around the time of labor onset. The activity of PG-9-ketoreductase, which interconverts the E and F series of PGs, was 2-3 orders of magnitude less than that of PG dehydrogenase. Using a dual chamber perfusion apparatus, we demonstrated that similar amounts of PGE2 were secreted from the fetal (amnion) and maternal (chorio-decidua) surfaces, and this ratio did not change with labor. Using radiolabeled PGE2, radioactivity traversed full thickness membranes at the rate of 4%/h. Only approximately 12% of the transferred radioactivity remained as intact PGE2, and very little conversion to PGF2 alpha was detected. No changes in transfer were detected around the onset of labor. We conclude that it is unlikely that PGE2 produced in the amnion acts directly on the myometrium.

Inflammatory pseudotumour of the liver

Inflammatory pseudotumours of the liver are uncommon, usually mistaken for malignant lesions and resected. This report describes the presentation of an inflammatory pseudotumour of the liver in a 28-year-old male which was demonstrated on C.T. scanning and diagnosed by percutaneous needle biopsy. This case was treated conservatively and spontaneously resolved within four months, emphasising the need to consider this lesion in the differential diagnosis of an intrahepatic mass.

Randomized trial of laser scalpel for modified radical mastectomy

The efficacy of a contact neodymium yttrium-aluminium-garnet laser scalpel was assessed during breast surgery. Forty consecutive women undergoing modified radical mastectomy were randomized to operation performed with a conventional or laser scalpel. The laser scalpel was associated with a significant reduction in mean operative blood loss (149 versus 421 ml; 95 per cent confidence interval of difference 176-368 ml, P < 0.001), but the mean operating time was longer (105 versus 80 min; 95 per cent confidence interval of difference 16-34 min, P < 0.001). No significant differences were found in the volume of postoperative wound drainage, incidence of axillary seroma, postoperative pain score or time to return of shoulder mobility. Use of a laser scalpel in breast surgery cannot be recommended.

Detection of tumour necrosis factor alpha and interleukin-1 beta in the rheumatoid osteoarthritic cartilage-pannus junction by immunohistochemical methods

During inflammation the rheumatoid synovial membrane is invaded by a number of different cell types. When activated most of these cells produce cytokines including tumor necrosis factor alpha (TNF alpha) and interleukin-1 beta (IL-1 beta). These cytokines are believed to stimulate production of degradative enzymes and disturb the equilibrium between such enzymes and their inhibitors resulting in tissue damage. In this study we investigated the localisation of TNF alpha and IL-1 beta at the cartilage-pannus junction (CPJ). Here, cytokines are well placed to influence the integrity of articular cartilage. Tissue was derived from advanced rheumatoid (RA) and, as a comparison, osteoarthritic (OA) joints at the time of replacement surgery (arthroplasty). Antibody staining of fixed serial sections of tissue localised cells that were associated with IL-1 beta and TNF alpha. Cell markers for macrophages and endothelial cells were included to provide positive identification of the cytokine-associated cells. Analysis of these sections revealed that both TNF alpha and IL-1 beta were associated with macrophages, particularly those in the synovium overlying cartilage (pannus) and endothelial cells. Positive staining was seen at the CPJ in RA and in similarly located tissue in OA. The similar distribution of cytokines in OA was unexpected even if the overall numbers of tissue and infiltrating cells in the CPJ were different in the two diseases. This highlights the possible role played by endogenous inhibitors [1, 2] in influencing the degree of cytokine activity necessary to explain the different pathogenic mechanisms in RA and OA.

Immunohistochemical analysis of p53 expression in anal squamous neoplasia

AIMS

To determine the pattern of expression of the p53 tumour suppressor gene product in anal squamous neoplasia, and to determine if this could be used as a marker of disease progression. The association between p53 expression and human papillomavirus (HPV) 16 DNA status of the anal lesions was also investigated.

METHODS

The presence and localisation of the p53 protein in formalin fixed, paraffin wax embedded specimens of anal squamous epithelium (normal and neoplastic) was examined using immunohistochemical staining with a panel of two monoclonal antibodies (DO-1, DO-7) and one polyclonal antibody (CM-1). Thirty nine normal anal epithelia, 14 anal intraepithelial neoplasia (AIN) grade 1, seven AIN 2, and 20 AIN 3 specimens were obtained from patients without demonstrable invasive disease; twelve AIN 3 specimens adjacent to invasive disease and 34 anal squamous cancers were also examined. Genomic DNA from all 126 specimens was extracted and analysed for HPV 16 DNA using the polymerase chain reaction (PCR).

RESULTS

Nuclear p53 was strongly expressed in 67% (23/34) of invasive anal squamous tumours, 75% (9/12) of AIN 3 specimens adjacent to invasive disease, and in 60% (12/20) of AIN 3 specimens obtained from patients without demonstrable invasive disease. Two of the patients in the latter group with positively staining specimens subsequently developed invasive tumours which had staining characteristics similar to those of the AIN 3 specimens. p53 protein was expressed in very low concentrations in low grade AIN and not at all in normal anal squamous epithelium. In those specimens which stained positively for p53, HPV 16 DNA sequences were detected in 69.5% (16/23) of invasive disease, 77.7% (7/9) of AIN 3 adjacent to invasive disease, 75% (9/12) of AIN 3 obtained from patients without demonstrable invasive disease, 33.3% (2/6) of AIN 2, and in 40% (2/5) of AIN 1. There was no significant correlation between p53 immunostaining and HPV 16 DNA status (p < 0.05).

CONCLUSIONS

Aberrant expression of the p53 gene product is probably involved in the pathogenesis of anal squamous neoplasia. Long term follow up studies of all patients with AIN are required to determine if this could be used as a marker of likely disease progression from high grade AIN to invasive disease. There does not seem to be an association between the presence or absence of HPV 16 DNA sequences and mutant p53 proteins in anal squamous neoplasia.

C-myc oncogene expression in anal squamous neoplasia

AIMS

To determine the pattern of c-myc oncogene expression in anal squamous neoplasia and to determine if this could be used as a marker of disease progression.

METHODS

The presence and localisation of the c-myc gene product p62 in archival specimens of anal squamous epithelium, normal and neoplastic, was examined using immunohistochemical staining with the monoclonal antibody Myc1-6E10. Ten normal and epithelia, 10 anal intraepithelial neoplasia (AIN) III, and 31 anal squamous cancers were examined.

RESULTS

There was a noticeable difference between the staining characteristics of invasive tumours, normal anal epithelium, and AIN III. Intense, diffuse, mixed nuclear and cytoplasmic (n = 14) and exclusively nuclear (n = 8) staining in 22 of 31 (71%) of invasive anal tumours was observed. All positively staining tumours were well differentiated histologically, while the negatively staining nine of 31 (29%) were poorly differentiated (n = 7) and moderately well differentiated (n = 2). In six positively staining tumour sections adjacent areas of AIN III and non-dysplastic anal epithelium had staining characteristics similar to those of the invasive component. Staining in both normal anal epithelium (4/10) and AIN III specimens obtained from patients without a history of invasive disease (8/10) was less intense, focal in distribution, and exclusively nuclear. No difference in staining characteristics could be detected in these two groups.

CONCLUSIONS

The results of this study suggest that c-myc oncogene expression is implicated in the pathogenesis of anal squamous neoplasia, and that immunohistochemical staining for c-myc protein may be helpful in identifying those AIN III lesions most likely to progress to invasive tumours.

The identification of informative parameters in the flow cytometric analysis of breast carcinoma

DNA ploidy and the measurement of proliferation or S-phase fraction are both of prognostic significance in breast cancer, yet clinical use is minimal in the U.K. Immunohistochemistry is, however, used to aid diagnosis, so a panel of antibodies were analysed by flow cytometry to assess their predictive value for prognosis, tumour stage and grade. Of 10 parameters tested on 202 breast tumour samples, tumour cell proliferation and DNA ploidy were the two most informative; cytokeratin staining, natural killer and B-cell infiltration also proved to be of value but there was no prognostic value in measuring tumour infiltrating monocytes, helper/suppressor T-cell ratios, tumour cell reactivity with carcinoembryonic antigen or human milk fat globulin antibodies. For each of the informative parameters, scores numerically weighted towards a poorer prognosis were derived which when combined, correlated with tumour grade, stage and prognosis. Such data interpretation is objective, and can be transposed to other human tumours.

Synthetase competition and tRNA context determine the in vivo identify of tRNA discriminator mutants

The discriminator nucleotide (position 73) in tRNA has long been thought to play a role in tRNA identity as it is the only variable single-stranded nucleotide that is found near the site of aminoacylation. For this reason, a complete mutagenic analysis of the discriminator in three Escherichia coli amber suppressor tRNA backgrounds was undertaken; supE and supE-G1C72 glutamine tRNAs, gluA glutamate tRNA and supF tyrosine tRNA. The effect of mutation of the discriminator base on the identity of these tRNAs in vivo was assayed by N-terminal protein sequencing of E. coli dihydrofolate reductase, which is the product of suppression by the mutated amber suppressors, and confirmed by amino acid specific suppression experiments. In addition, suppressor efficiency assays were used to estimate the efficiency of aminoacylation in vivo. Our results indicate that the supE glutamine tRNA context can tolerate multiple mutations (including mutation of the discriminator and first base-pair) and still remain predominantly glutamine-accepting. Discriminator mutants of gluA glutamate tRNA exhibit increased and altered specificity probably due to the reduced ability of other synthetases to compete with glutamyl-tRNA synthetase. In the course of these experiments, a glutamate-specific mutant amber suppressor, gluA-A73, was created. Finally, in the case of supF tyrosine tRNA, the discriminator is an important identity element with partial to complete loss of tyrosine specificity resulting from mutation at this position. It is clear from these experiments that it may not be possible to assign a specific role in tRNA identity to the discriminator. The identity of a tRNA in vivo is determined by competition among aminoacyl-tRNA synthetases, which is in turn modulated by the nucleotide substitution as well as the tRNA context.

Anal intraepithelial neoplasia: part of a multifocal disease process

Invasive carcinomas of the anogenital epithelium share a common aetiological factor--human papillomavirus (HPV) type 16. Although genital intraepithelial neoplasia may be multifocal, there have been no studies of the prevalence of anal intraepithelial neoplasia in women with intraepithelial neoplasia of the genital tract. We tested the hypothesis that women with high-grade cervical intraepithelial neoplasia are at higher risk of disease in the anus than are control women of similar age with no history of anogenital neoplasia. 29 (19%) of 152 women with cervical intraepithelial neoplasia grade III had histological evidence of anal intraepithelial neoplasia. Of the 29 patients, 11 had grade III anal lesions; 2 of those women had concomitant invasive anal squamous-cell carcinomas. Only 7% (8/115) women with high-grade lesions of the cervix alone had evidence of anal intraepithelial neoplasia; by contrast, 57% (21/37) of those with more than one focus of intraepithelial neoplasia (cervix plus vulva, vagina, or both) had anal lesions. HPV 16 DNA was identified in 18 (51%) of 35 anal biopsy samples in the study group. No evidence of anal intraepithelial neoplasia was found in the control group (50 women), although 2 patients had grade I cervical lesions. HPV 16 DNA was identified in 12 (24%) of biopsy samples from the cervix and 7 (14%) from the anus in the control group; all 7 women with anal HPV 16 had concomitant cervical infection. The role of anal examination in the assessment of women with any focus of genital intraepithelial neoplasia requires further investigation.

Comparison of a new pressurized saline canister versus syringe irrigation for laceration cleansing in the emergency department

STUDY OBJECTIVE

Studies have documented the efficacy of normal saline irrigation in decreasing wound infection rates. Wounds traditionally are irrigated using a syringe and needle with manual injection of fluid, a time- and labor-intensive method. We compared irrigation times and infection rates for wounds cleansed with syringe irrigation versus a new, single-use canister of pressurized (8 psi) sterile normal saline.

DESIGN

Prospective, randomized, controlled.

SETTING

Two Level I emergency departments in tertiary care hospitals, both with emergency medicine residency programs.

PARTICIPANTS

Patients with lacerations requiring closure were eligible. Exclusion criteria were wounds above the clavicle more than ten hours old, wounds below the clavicle more than six hours old, insulin-dependent diabetes mellitus, or antibiotic or steroid therapy. Patients (550) were entered between August 1, 1990, and January 31, 1991. Characteristics of the two treatment groups were similar for patient age, age of the wound, size and depth of the laceration, and number of sutures.

INTERVENTIONS

Lacerations were irrigated with 250 mL saline in a syringe or 220 mL saline in a pressurized canister for each 5 cm of laceration. At follow-up or suture removal, patients were evaluated for signs of wound complications (cellulitis, ascending lymphangitis, purulent discharge, or dehiscence).

MAIN RESULTS

The mean irrigation time for the pressurized canister group (281) was 3.9 minutes versus 7.3 minutes in the syringe irrigation group (254) (P < .0001). The complication rate for the pressurized canister group was 5.0% compared with 3.6% for the syringe irrigation group (not significant, P = .50). Only three of the 20 total complications required antibiotics (two in the pressurized canister group, one in the syringe irrigation group).

CONCLUSION

Syringe irrigation times were nearly twice as long as the pressurized canister irrigation times. Use of the pressurized canister facilitates ease of irrigation and markedly decreases the time involved in this traditionally labor-intensive activity. In addition, delivery of the saline is no longer operator dependent, ensuring generation of pressures appropriate for wound cleansing. The pressurized canisters may be useful in standardizing irrigation in wound management research.

Reduced GAP-43 message levels are associated with increased neurofibrillary tangle density in the frontal association cortex (area 9) in Alzheimer's disease

We previously suggested the hypothesis that defective neuronal plasticity is a major neurobiological deficit causing the dementia of Alzheimer's disease (AD). We used message levels of the growth-associated protein, GAP-43, as a marker of axonal plasticity to examine the hypothesis of defective neuronal plasticity in AD. When all AD cases are combined, the average level of GAP-43 message in area 9 of the AD frontal association cortex was not significantly different from the level in the comparably aged control cortex. Differentiation of AD cases on the basis of neurofibrillary tangle (NFT) density revealed that in AD cases with high tangle density average GAP-43 message level was reduced fivefold relative to levels in AD cases with low NFT density. AD cases with low neurofibrillary tangle density had levels of GAP-43 message that were not significantly different from the levels of normal controls. Differentiation of AD cases on the basis of neuritic plaque density did not indicate as strong a relationship to GAP-43 message level. The association between neurofibrillary tangle density and GAP-43 message level suggests the hypothesis that neurofibrillary tangles may reduce GAP-43 expression. Data of others show a relationship between high NFT density and reduced levels of synaptophysin-like immunoreactivity and reduced cerebral glucose metabolism. These data combine to suggest a set of AD cases with high NFT density, reduced axonal plasticity, reduced synaptic density, and reduced cerebral glucose metabolism--all variables that may be directly related to the functioning of the brain.(ABSTRACT TRUNCATED AT 250 WORDS)

Nucleolar organiser regions (AgNORS) in anal intraepithelial neoplasia and invasive anal squamous cell carcinoma

AIM

To evaluate the usefulness of counting nucleolar organiser region associated proteins (AgNORs) in the management of anal squamous neoplasia.

METHOD

Using a silver staining technique for NOR associated proteins, 32 routinely processed paraffin wax embedded sections of anal epithelium were assessed. These consisted of normal anal epithelium (n = 9), anal intraepithelial neoplasia (AIN) grades I (n = 5), and III (n = 13), and invasive squamous neoplasia of the anus (n = 5).

RESULTS

The median AgNOR counts for every 100 cells are as follows: normal anal epithelium 2.15 (95% CI 1.89-3.94); AIN I 3.21 (95% CI 2.89-7.14); AIN III 4.32 (95% CI 4.00-8.10); and invasive squamous cell carcinoma of the anus 5.51 (95% CI 2.48-10.62). There were significant differences between AgNOR counts in anal cancer and normal epithelium (p < 0.05; Mann-Whitney U test)), AIN III and normal anal epithelium (p < 0.005), and AIN III and AIN I (p < 0.05). No significant differences were observed between AIN I and normal anal epithelium, anal cancer and AIN I, and anal cancer and AIN III. There was a considerable degree of overlap among the different groups.

CONCLUSIONS

Despite the strong association between AgNOR values and degree of dysplasia, the variability within pathological grade may preclude the adoption of this technique on its own as a prognostic indicator. It may, however, be useful in conjunction with other markers of neoplastic growth such as c-myc oncogene amplification or overexpression as a marker of disease progression in AIN and invasive anal squamous cell cancer.

Is there still a place for prolonged bladder distension?

Over a 2-year period, 31 patients underwent prolonged hydrostatic bladder distension for benign and malignant bladder disease in this unit. Of these, 29 patients had benign functional disorders or bladder contracture, and in 2 patients hydrodistension was performed for complications of treatment for bladder neoplasia. Of the 29 patients with benign disease, 6 observed marked improvement and 8 some improvement in their symptoms, and 12 received no benefit. Patients with detrusor hypersensitivity fared better than those with detrusor instability or interstitial cystitis. A patient with malignant bladder disease died soon after the procedure as a result of a myocardial infarction. Problems attributed to the hydrostatic balloon catheter were responsible for 2 failures. The regional anaesthetic technique failed to provide adequate anaesthesia for hydrodistension in 9 procedures and limited the duration to 2 h in 13 others. Following recall of the perished balloon catheters by the manufacturer, and the introduction of continuous spinal anaesthesia, the number of technical failures has been reduced. This technique still has an important role to play in the relief of severe symptoms unresponsive to medical treatment, but it is important that ideal conditions are provided for hydrodistension in order to ensure maximum success, particularly when the alternative is major surgery.

Delay in fixation does not affect the immunoreactivity of proliferating cell nuclear antigen (PCNA)

The effect of delayed fixation on the immunoreactivity of proliferating cell nuclear antigen (PCNA) was investigated using eight breast carcinomas. Topologically shuffled samples of each tumour were immersed in fixative at times of 0.5, 1, 2, 4, 6, 18, and 24 h after surgical removal. In addition to a PCNA index (percentage of positive cells per 1200 tumour cells), a semi-quantitative PCNA grading system was used, based on estimates of more than or less than 50 per cent of positive tumour cells at each time interval. The PCNA index of six tumours increased by a mean of 10 per cent with a fixation delay of 24 h. The PCNA grade of all eight tumours showed no change with delayed fixation.

Radical breast surgery with a contact Nd:YAG laser scalpel

The use of a contact Nd:YAG laser scalpel during radical and modified radical mastectomy was evaluated in 18 patients with carcinoma of the breast. The laser scalpel performed well as a haemostatic tool, the associated mean blood loss for modified radical mastectomy being 132 ml. Operating time, operative blood loss, laser energy required and postoperative wound drainage were all related to patient obesity, correlating significantly with body weight and/or breast weight. The incidence of axillary seroma was not reduced by laser surgery and occurred in 53% of patients undergoing modified radical mastectomy. The Nd:YAG laser scalpel is an excellent haemostatic tool but it does not appear to have any other advantages over conventional surgery for mastectomy.

Effect of tissue pressure on contact laser insults

The effect of variations in tissue pressure transmitted through contact laser probes during tissue ablation has been investigated. Weights of 10 and 50 g were transmitted through the tip of the probes onto the gastric and colorectal wall. At all laser energies the depth of tissue vaporization was significantly greater at the higher tissue pressure with perforation of the viscus occurring at laser energies above 10 J. The lateral zones of thermal tissue necrosis were not influenced by tissue pressure. Deformation of the wall of the viscus under the pressure of the probe was identified as a sign of excessive tissue pressure likely to result in perforation of any tissue of similar thickness to the normal gastric or colorectal wall.

Preliminary evaluation of a new high power diode laser

A high-powered semiconductor diode laser (805 nm) has recently been developed for medical use. The laser-tissue interactions of this wavelength have been compared with Nd:YAG (1064 nm). When used in the contact mode, the extent of tissue vaporization and zones of thermal necrosis produced by these two lasers were similar. The diode laser was also an effective and haemostatic laser scalpel. This compact laser unit has potential advantages over existing Nd:YAG lasers.

Characteristics and outcome of hospitalized adolescent girls with conduct disorder

Fifty-five adolescent girls with conduct disorder from a psychiatric hospital were examined with a structured interview schedule and then reevaluated 2 to 4 years later. The majority also had depressive or anxiety disorders. The criteria used for conduct disorder were less weighted toward violent crime and differed from the criteria in DSM-III-R. Their outcome was poor; 6% had died a violent death, the majority had dropped out of school, one-third were pregnant before the age of 17, half were rearrested, and many suffered traumatic injuries. Diagnoses of depression or anxiety disorders at the index admission were not associated with a better outcome.

Management of Generalized Faecal Peritonitis-Can We Do Better?

Generalized faecal peritonitis is associated with a mortality of over 50% in most series of cases. Despite great improvements in the standards of intensive care the morbidity and mortality associated with this condition have not improved, in part due to recurrent intra-abdominal sepsis. This preliminary study investigated the role of laparotomy, repeated abdominal lavage and debridement to determine whether such a policy might lead to an improvement in outcome. Of six cases studied three had perforated diverticular disease, two had Crohn's disease. Twenty lavages were performed on these six patients who had a mean ICU stay of 8 days. Five out of the six patients left hospital and remain well, one patient died of septicaemia and pre-existing renal failure. This study found that laparotomy, repeated abdominal lavage and debridement may be effective in reducing the morbidity and mortality of generalized faecal peritonitis and further study of this technique is appropriate.

Loss of monomorphic and polymorphic HLA antigens in metastatic breast and colon carcinoma

MHC class I antigens are intimately involved in intercellular communication, and recognition by cytotoxic T cells. Thus tumour cells that fail to express them may be at a growth or metastatic advantage. A series of ten colorectal and ten breast carcinomas, and their respective lymph node metastases, were examined immunohistologically using monoclonal antibodies (mAb) against both monomorphic and A2 polymorphic determinants, and beta-2-microglobulin (beta 2m). Four colon polypoid adenomas stained positively throughout, but 6/10 primary tumours had partial or complete loss of expression of monomorphic determinants using mAb W6/32: two node and the liver metastasis showed less, four more expression. Similar results were seen for beta 2m. HLA-A2 expression was absent or reduced in 4/4 colon tumours and all their metastases. Among the breast tumours, W6/32 staining was absent or reduced in 2/10, and node deposits showed two with less reactivity than their primary. Beta 2m staining was reduced or absent in 8/10 primaries and all the node metastases; in every case in which beta 2m was detected in the primary tumour their corresponding lymph node metastasis showed a decreased expression. HLA-A2 expression was absent or reduced in 3/4 primary breast carcinomas, and all their metastases. These results show that individual human colon and breast carcinomas often have a reduced HLA class I antigen expression, which apparently confers a metastatic advantage.

Is the grading of breast carcinomas affected by a delay in fixation?

The effect of delay in fixation on the modified Bloom and Richardson grade of eight breast carcinomas was investigated. Topologically shuffled samples of each tumour were immersed in fixative at times of 0.5, 2, 4, 6, 18 and 24 h after surgical removal. The grade of each tumour was assessed at delays of 0.5 and 6 h. The tubule formation and nuclear pleomorphism components of the grade showed no change with a delay in fixation of 6 h. The number of mitotic figures declined by a mean of 53% over the same period and this resulted in a decrease in the histological grade of one of the tumours. The implications of these findings for the handling of breast specimens in a diagnostic histopathological laboratory are discussed.

Pharmacokinetics and immune response of 131I-chimeric mouse/human B72.3 (human gamma 4) monoclonal antibody in humans

Chimeric B72.3, composed of the V-regions of murine B72.3 and the constant regions of human immunoglobulin G4 heavy and kappa light chain, was administered as a 131I-labeled conjugate to 12 patients with metastatic colon cancer. Seven of these patients had an antibody response after initial infusion, and the immune response was primarily directed to the murine V-region, although a small proportion of the antibody response was directed to topographical epitopes requiring the presence of both murine V-region and human CH-1 and kappa constant regions (neo-epitopes). The pharmacokinetics included a plasma disappearance curve best fit by a two-compartmental model with an alpha t 1/2 of 18 +/- 7 h and a beta t 1/2 of 224 +/- 66 h. A second infusion of the same dose of 131I-chimeric B72.3 was administered to four of these patients 8 wk after the first infusion. Two patients who had a high antibody response to initial infusion had an anamnestic antibody response, and the infused ch-B72.3 rapidly disappeared from the circulation with associated immune complexes and free 131I in the plasma. One patient with no initial antibody response had no antibody response and identical pharmacokinetics on second infusion. One patient with a modest transient antibody response to initial infusion had no antibody response on second infusion and a modest shortening of plasma circulation. Thus, the human immunoglobulin G4 isotype chimeric B72.3 monoclonal antibody has a plasma half-life 6 to 8 times as long as murine B72.3 and retains considerable immunogenicity in some patients which can adversely affect repetitive infusions.

Cytomegalovirus (CMV)-specific intravenous immunoglobulin for the prevention of primary CMV infection and disease after marrow transplant

Cytomegalovirus (CMV)-specific immunoglobulin (IVIG) was evaluated in a randomized controlled trial in CMV-seronegative marrow transplant patients with seropositive marrow donors for the prevention of primary CMV infection during the first 100 days after transplant. Patients received 200 mg/kg CMV IVIG on days 8 and 6 before transplant, the day after transplant, weekly for the first month, and then every 2 weeks to complete 10 doses. Patients were followed with weekly CMV cultures and serologic studies and for clinical and histologic evidence of CMV disease. Sixty patients were evaluable in each group. There was significantly less CMV excretion (P = .04) and viremia (P = .01) in the treatment group. However, the incidence of CMV disease including CMV pneumonia, CMV enteritis, and CMV syndrome (fever, leukopenia, hepatitis) was not statistically different. There was also no difference in median time of onset of CMV infection or disease, median number of hospital days, or survival between the two groups.

Diagnostic difficulties in patients with a pancreatic mass

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Parameters for and safety of contact Nd:YAG laser irradiation of early gastric cancer: an in vitro study

Early gastric cancers have been treated by endoscopic contact Nd:YAG laser irradiation. The extent of thermal damage produced by this laser system has been inadequately investigated. In an in vitro study we have shown that contact laser probes produce consistent and reproducible thermal lesions in the human stomach wall. Contact laser energies of 40 to 60 joules are optimal for the ablation of early gastric cancer. Energies greater than 90 joules are associated with a high incidence of gastric perforation. Contact laser probes may have advantages over non-contact laser techniques for the endoscopic treatment of early gastric cancer in patients who are unfit for major surgery.

The use of CA15.3 as a serum tumour marker in breast carcinoma

There is, as yet, no tumour marker which is sufficiently specific and sensitive for use in the routine assessment of breast cancer patients. CA15.3 is a recently described tumour marker determined by two monoclonal antibodies. We have estimated CA15.3 by immunoradiometric assay in 187 patients attending a breast clinic. Eighty-one patients with benign disease were used as controls and 32 U/ml was taken as the upper limit of the normal range (means + 3SD = 31.7). Of 58 women with Stage I and II disease, only four had abnormal concentrations of CA15.3 and all are disease-free at a mean follow-up of 31 months. Seven women with normal CA15.3 concentrations developed recurrent disease at a mean of 18.7 months (range 10-25 months). Seven-day postoperative values were significantly lower than pre-operative values. There was no association between the CA15.3 value and the axillary nodal status. The patients with disseminated disease had a wide range of CA15.3 concentrations and there was no association between the CA15.3 concentration and the apparent tumour load.

Reaction of patients on chronic dialysis to discussions about cardiopulmonary resuscitation

A total of 146 patients, 91 on chronic hemodialysis and 55 on chronic peritoneal dialysis, were asked to declare their choice of cardiopulmonary resuscitation (CPR) in cases of cardiopulmonary arrest. Fifty-four patients (37%) declined CPR. The severity of medical disability and the presence of diabetes were independent predictors of refusal of CPR. The pattern of patient reaction to CPR gave valuable information about patients' comprehension of this issue and about patients' ability to cope emotionally with CPR. On the basis of the reaction pattern, approximately 95% of the patients interviewed understood CPR and reacted to it appropriately. Questioning dialysis patients about their CPR preference is feasible and fruitful.