Identification and characterization of a pro-tumor necrosis factor-alpha-processing enzyme from the ADAM family of zinc metalloproteases

Tumor necrosis factor-alpha (TNF) is initially expressed as a 26-kDa membrane-bound precusor protein (pro-TNF) that is shed proteolytically from the cell surface, releasing soluble 17-kDa TNF. We have identified human ADAM 10 (HuAD10) from THP-1 membrane extracts as a metalloprotease that specifically clips a peptide substrate spanning the authentic cleavage site between Ala76 and Val77 in pro-TNF. To confirm that HuAD10 has TNF processing activity, we cloned, expressed, and purified an active, truncated form of HuAD10. Characterization of recombinant HuAD10 (rHuAD10) suggests that this enzyme has many of the properties (i.e. substrate specificity, metalloprotease activity, cellular location) expected for a physiologically relevant TNF-processing enzyme.

Partial reversal of heparin anticoagulation by intravenous protamine in abciximab-treated patients undergoing percutaneous intervention

Serious hemorrhage and vascular complications after abciximab therapy are associated with elevated activated clotting time values. Our preliminary experience suggests that low-dose intravenous protamine administration is both safe and effective in reducing elevated in-laboratory activated clotting time values and the potential for serious hemorrhage in abciximab-treated patients.

Screening for abdominal aortic aneurysm during transthoracic echocardiography in a hypertensive patient population

This study was undertaken to determine the utility of transthoracic echocardiography as a screening test for occult abdominal aortic aneurysm in hypertensive patients older than 50 years of age. Longitudinal and transverse images of the abdominal aorta were obtained during the subcostal portion of the transthoracic echocardiogram. Abdominal aortic aneurysm was defined as an abdominal aortic dimension (antero-posterior or lateral) > or = 3.0 cm. Exclusion criteria included prior abdominal aortic aneurysm repair, known abdominal aortic aneurysm, or inadequate images of the abdominal aorta (nine patients). Two hundred patients (107 men, 93 women; mean age 71 years, range 51 to 92 years) met the study inclusion criteria. An occult abdominal aortic aneurysm was identified in 13 patients (6.5%). Sixty-nine percent of the abdominal aortic aneurysm patients were men, with a mean age of 73 years and a mean duration of hypertension of 11 years. Seventy-seven percent had a history of tobacco use, and 15% had a positive family history of abdominal aortic aneurysm. All aneurysms were infrarenal in location, with abdominal aortic aneurysm diameter ranging from 3.0 to 5.2 cm (mean 3.9 cm). Laminated thrombus was present in six patients (46%), and in one patient a right common iliac artery aneurysm was also detected. Imaging of the abdominal aorta during transthoracic echocardiography required an average of 6.7 minutes (range 4 to 10 minutes). In conclusion, the abdominal aorta could be accurately imaged in the majority of patients (96%) undergoing transthoracic echocardiography in this study. The incidence of occult abdominal aortic aneurysm in hypertensive patients older than 50 years of age is significant (6.5%). Screening for occult abdominal aortic aneurysm in this patient population should be a routine extension of the transthoracic echocardiogram.

Predictors of human immunodeficiency virus counseling and testing among sexually transmitted disease clinic patients

OBJECTIVES

To determine the predictors of prior or current, and repeat human immunodeficiency virus (HIV) testing.

STUDY DESIGN

Cross-sectional survey.

METHODS

Sexually transmitted disease (STD) clinic patients who participated in a blinded HIV seroprevalence survey completed a voluntary questionnaire regarding their reasons for accepting or declining HIV testing.

RESULTS

Eighty-seven percent of participants reported a previous HIV test or were HIV testing the day they completed the questionnaire. African Americans were less likely to have been HIV tested (adjusted odds ratio 0.3, 95% confidence limits, 0.1, 0.8). The most common reasons for testing were to be reassured and to receive medical care if infected. The most common reason for not testing was that nontesters did not think that they were infected. Repeated testing was reported by 51% of the participants and was more frequent among patients who were older or members of high-risk groups (P < 0.05). Patients tested repeatedly to confirm a prior HIV test result or because of continued risky behavior.

CONCLUSIONS

Testing for HIV is frequent among STD clinic patients but less so among African Americans. Receipt of medical care appears to be an important motivation for HIV testing, whereas lack of perceived risk may discourage testing. Continued high-risk behavior contributes to repeat HIV testing.

Physiological effects of bulimia nervosa on the gastrointestinal tract

Bulimia nervosa is an eating disorder characterized by frequent bouts of binge eating accompanied by compensatory behaviour for preventing weight gain (purging). It is estimated that 3% to 5% of young women are affected by bulimia nervosa, and its prevalence is increasing. Bulimia nervosa afflicts both sexes and all races. It can lead to serious medical complications. The expression of the disease in the gastrointestinal tract may have a critical role in the diagnosis of bulimia nervosa. Physiological effects of bulimia nervosa on the gastrointestinal tract include dental caries and enamel erosion; enlargement of the parotid gland; esophagitis; changes in gastric capacity and gastric emptying; gastric necrosis; and alterations of the intestinal mucosa. Identification of any of these factors may aid in establishing an early diagnosis, which has been shown to increase the likelihood of recovery.

Safe pancreas transplantation in patients with coronary artery disease

BACKGROUND

This study was conducted to determine the risk of clinically significant posttransplant cardiac events (PCEs) in a cohort of diabetic patients referred for pancreas transplantation.

METHODS

Between April 1991 and December 1995, 316 insulin-dependent diabetics were evaluated for pancreas transplantation. Patients were assessed for risk factors for coronary artery disease (CAD), and underwent screening for significant CAD by a standardized algorithm that included selective coronary angiography. For the 3-year period following transplantation, PCEs were identified, and related to pretransplant cardiac risk factors.

RESULTS

Only four patients (1.3%) were turned down for cardiac contraindications. Coronary angiography was done in 74 patients (27% of the active transplant candidates) during the evaluation period because of the patient's history or a positive stress test. Significant coronary artery stenoses were found in 54% of the patients catheterized. Twenty-five of these 40 patients (63%) underwent revascularization with percutaneous transluminal coronary angioplasty and/or coronary artery bypass grafting. A total of 359 organs were subsequently transplanted into 194 of these patients. No deaths occurred within 30 days of any of the transplants; four percent of transplant recipients died of cardiac causes within the follow-up period (median 23 months). Those with no pretransplant evidence of CAD had significantly lower rates of PCE (2% and 8% at 1 and 3 years, respectively) than those with pretransplant evidence of CAD (11% and 29% at 1 and 3 years, P<0.01; relative risk, 4.3).

CONCLUSIONS

Routine cardiac screening of pancreas recipients with selective angiography and revascularization allows patients with significant CAD to safely undergo pancreas transplantation. Patients should rarely be excluded from pancreas transplantation for cardiac causes.

Seroprevalence of and risk factors for hepatitis A infection among young homosexual and bisexual men

To evaluate hepatitis A infection among young homosexual and bisexual men, 411 men aged 17-22 years were surveyed at 26 public venues in San Francisco and Berkeley. Seroprevalence of hepatitis A infection was 28.0% (95% confidence interval [CI], 23.7%-32.6%). Recent infection was evident in 3.3% of susceptible men (95% CI, 1.6%-5.9%). Independent predictors of hepatitis A infection were Latino ethnicity (odds ratio [OR] = 5.3; 95% CI, 3.1-8.9), having > or = 50 lifetime male sex partners (OR = 1.8; 95% CI, 1.1-3.0), less than high school education (OR = 2.2; 95% CI, 1.2-4.1), and being a high school graduate (OR = 1.7; 95% CI, 1.0-2.9). Independent predictors of recent infection were less than high school graduate (OR = 7.6; 95% CI, 1.9-30.5), insertive anal intercourse (OR = 5.6; 95% CI, 1.0-32.8), and sharing needles without cleaning them (OR = 32.1; 95% CI, 3.0-346). Hepatitis A is a common infection in young homosexual men and is associated with sexual and drug-using behaviors.

Increased living donor volunteer rates with a formal recipient family education program

We have generally encouraged living donation among our kidney recipients. However, an examination of our clinical practice revealed inconsistencies in the depth and content of information transmitted to kidney recipient families regarding living donation. We therefore initiated a structured education program, including an educational video, to ensure that all recipient families would receive a similar exposure to a standard block of information. After the program had been functioning for over a year, we compared the living donor (LD) volunteer rates between the 3-year period before (BEFORE) and the 18 months after (AFTER) initiation of the formal education program. There were 1,363 patients registered on our kidney transplantation waiting list during the 54-month study period (757 white [56%] and 580 black [43%]). We found that 33.4% of the kidney transplant candidates in the period BEFORE the LD education program had at least one potential LD tissue typed, compared with 39.4% in the period AFTER starting the program (P = 0.03). The increase in the proportion of patients with potential donors was greatest among the black (P < 0.05) and elderly (P < 0.01) registrants, which were the groups with the lowest volunteer rates before the program began. Among the registrants with at least one potential donor, the percentage of registrants who ultimately received an LD transplant was highly correlated with the number of donors (R = 0.98). The rate of LD kidney transplantation was significantly higher (P = 0.02) for the patients referred in the period AFTER initiation of the LD education program compared with the period BEFORE the program. The 1- and 3-year graft survival rates for the 170 LD transplants performed in these patients were 96.9% and 93.2%, respectively. These were significantly better than the corresponding 83.9% and 71.4% rates for the 341 kidney transplants from cadaver donors in these registrants (P < 0.001). Black recipients of LD transplants had graft survival rates comparable to whites; the 3-year graft survival rate for LD transplants was 93.9% in whites and 90.6% in blacks (P = NS). We conclude that living kidney donor volunteer rates can be improved by a formal family education program, especially for subgroups of patients with low volunteer rates. A substantial benefit is derived by black patients, who generally experience low graft survival rates with cadaver-donor kidneys. A local formal LD education program is a useful adjunct to national organ donation campaigns.

Retroperitoneal actinomycosis masquerading as inflammatory pseudotumor

Inflammatory pseudotumors present clinically as mass lesions and microscopically show a spectrum of nonspecific inflammatory and regenerative changes. When the mesentery or retroperitoneum are involved, differentiation from inflammatory fibrosarcoma poses a diagnostic problem. The authors report on a 7-year-old boy who presented with fever, anemia, weight loss, and a retroperitoneal mass. Needle biopsy results of the mass showed features consistent with inflammatory pseudotumor. Examination of the resected mass showed actinomycosis.

Variability of diaphragm structure among healthy individuals

The ratio of the muscular cross-sectional area of the diaphragm (CSA(di)) to the axially projected area of the thorax (A(thor)) theoretically determines the strength of the inspiratory pump. We studied these dimensions in 37 healthy subjects by ultrasonography and anthropometry. In 21 subjects who did not train with weights, thickness of the diaphragm (t(di)), circumference of the rib cage (c(di)), and CSA(di) increased with height and with body weight. The increase of thoracic cavity dimensions with weight was similar to that described across a wide range of mammals and was consistent with the scaling principle of elastic similarity. CSA(di)/A(thor) showed considerable variability and was not systematically dependent on height or weight. The 15 adults who trained with weight-lifting had thicker diaphragms for comparable height and greater CSA(di)/A(thor) than the adults who did not train. We conclude that (1) the structural dimensions of the diaphragm and thorax show substantial variability, some of which is systematic with stature; (2) the variations of structure predict substantial variation of inspiratory strength which is not systematic with stature; (3) the muscular cross-section of the diaphragm is increased by general or specific training.

The introduction of generic workers into the ward team: an exploratory study

This study arose from a quantitative study that defined the role and resources required for the introduction of generic workers into the ward team. A month's trial was conducted to explore the staff attitudes and perceptions associated with such an introduction, thereby identifying potential problems and benefits that may influence successful introduction into the ward team. A small convenient sample that included trained, untrained and domestic staff was used. The methodological strategies in the study were semi-structured interviews, pre- and post-trial, and non-participant observations during the trial. The data obtained were transcribed and analysed using 'thematic content analysis' and 'within method triangulation'. The findings indicated positive support for the introduction of such workers and the transfer of responsibility from a central domestic team to the ward manager. The ward environment improved and nursing staff were freed from non-nursing activity, leaving more time for patient care. Recommendations to facilitate the smooth introduction of these workers are stated within the study and are now in place within the Trust. The introduction of these workers has been agreed and a staggered roll out of the project is underway in all wards across the Trust.

A comparison of selected mRNA and protein abundances in human liver

In order to obtain an estimate of the overall level of correlation between mRNA and protein abundances for a well-characterized pharmaceutically relevant biological system, we have analyzed human liver by quantitative two-dimensional electrophoresis (for protein abundances) and by Transcript Image methodology (for mRNA abundances). Incyte's LifeSeq database was searched for expressed sequence tag (EST) sequences corresponding to a series of 23 proteins identified on 2-D maps in the Large Scale Biology (LSB) Molecular Anatomy database, resulting in estimated abundances for 19 messages (4 were undetected) among 7926 liver clones sequenced. A correlation coefficient of 0.48 was obtained between the mRNA and protein abundances determined by the two approaches, suggesting that post-transcriptional regulation of gene expression is a frequent phenomenon in higher organisms. A comparison with published data (Kawamoto, S., et al., Gene 1996, 174, 151-158) on the abundances of liver mRNAs for plasma proteins (secreted by the liver) suggests that higher abundance messages are strongly enriched in secreted sequences. Our data confirms this: of the 50 most abundant liver mRNAs, 29 coded for secreted proteins, while none of the 50 most abundant proteins appeared to be secreted products (although four plasma and red blood cell proteins were present in this group as contaminants from tissue blood).

Comparison of a monoclonal antibody-based IgM capture ELISA with a neutralization assay for assessing response to trivalent oral poliovirus vaccine

Monoclone-based IgM capture ELISAs were developed for each of the three poliovirus serotypes and compared with a neutralization assay for detecting response to trivalent oral poliovirus vaccine among 224 infants. The IgM-based response rates were significantly higher than the neutralizing antibody-based rates: 95% versus 83% to poliovirus type 1, 99% versus 94% to poliovirus type 2, and 89% versus 59% to poliovirus type 3. IgM responses to the first vaccine dose were significantly associated between serotypes, suggesting that some of the discordance may reflect a heterotypic IgM response. When the response rates in 4 vaccine formulation groups were compared, group differences using the two assays were similar for poliovirus types 1 and 2 but not for type 3. Therefore, IgM results using these assays may not be adequate substitutes for neutralizing antibody results when determining vaccine response.

Measles vaccination of Thai infants by intranasal and subcutaneous routes: possible interference from respiratory infections

Reactogenicity and seroresponses were studied after standard doses of Edmonston-Zagreb measles vaccine were given intranasally (i.n.) and subcutaneously (s.c.) to 6-month-old Thai children. Few children given i.n. vaccine (2/31), but most (13/21) given s.c. vaccine, seroconverted. All but 1 of 51 children were seropositive after receiving vaccine s.c. at 9 months-of-age. Upper respiratory infection (URI) outbreaks with onsets in the week following vaccination occurred after each vaccination session and were equally common in all groups. URIs following i.n. vaccination at 6 months may have adversely affected response to i.n. vaccine, while URIs after s.c. vaccination at 9 months adversely affected final geometric mean antibody titers. I.n. measles vaccination does not appear to be an acceptable route for routine vaccination.

Intra- and perioperative complications associated with tandem and colpostat application for cervix cancer

PURPOSE

The purpose of this study was to chronicle the acute morbidity associated with the implantation of tandems and colpostats in women with carcinoma of the cervix; to determine factors that predispose to the development of such complications; and to assess whether the use of ultrasound allowed the apparatus to be safely implanted in women at relatively high risk for perforation of hollow viscous organs.

METHODS

A database from two Philadelphia institutions was used to assess the aforementioned factors among 143 tandems/colpostats inserted into 100 women with cervix cancer. Twenty patients had insertion under ultrasound guidance because of stenotic cervical os, fibrosis from external-beam irradiation, indeterminate orientation of endometrial cavity axis, or previous perforation. Univariate and multivariate analyses were performed to identify predictors of intra- and perioperative complications.

RESULTS

Intraoperative complications occurred in 7 of 143 placements (5%). These included uterine perforations (n = 4), vaginal lacerations (n = 2), and one instance of bladder perforation. Only older age, whether entered as a continuous or a dichotomous variable, was associated statistically with these complications. Perioperative complications (e.g., fever, bowel obstruction, exacerbation of chronic obstructive pulmonary disease, cardiac complication) occurred in 54 of 143 implanted women. In univariate analysis, older age and underlying chronic obstructive pulmonary disease (COPD) appeared to be associated with perioperative complications. A multivariate analysis showed that underlying COPD predisposed to perioperative complications during the first implant and that age over 60 years independently predicted for complications during any implant.

CONCLUSIONS

Intraoperative complications are relatively rare events. Ultrasonography seems to allow safe intrauterine insertion of the tandem despite the selection of difficult cases for this adjunctive imaging tool. Patient age over 60 years independently predicts for perioperative complications. COPD predicts for perioperative complications during the first but not the second implant, implying that physicians are able to optimize the medical management of pulmonary disease to allow a second implant to be performed more safely.

Use of the splenic and hepatic artery for renal revascularization in patients with atherosclerotic renal artery disease

Hepatorenal and splenorenal bypasses are gaining an increased popularity as an alternative to renal artery endarterectomy and aortorenal bypass in selected patients. However, there are few reports of the long-term results of this procedure. The purpose of this study was to assess the performance of the hepatic and splenic arterial sources in patients with atherosclerotic renal artery disease. We reviewed our 7-year experience between 1988-1995. A total of 146 operative renal artery reconstructions were performed, including 45 hepatorenal and/or splenorenal bypass in 38 patients, (19 male, 19 female, mean age 62 +/- 12 years) for treatment of renovascular hypertension, renal preservation or both. The mean preoperative creatinine was 2.95 mg/dl (2.11-3.47, 95% confidence limits). The average number of antihypertensive medications was 2.63. There was one postoperative death from myocardial infarction and two cases of early graft thrombosis, one of which was treated by thrombectomy reestablishing patency. In two patients with persistent hypertension selective angiography demonstrated high-grade anastomotic stenoses which were successfully dilated by balloon angioplasty. The postoperative mean creatinine decreased to 2.54 mg/dl (1.82-3.27, 95% confidence limits), (p = 0.17) and the average number of antihypertensive medications decreased to 1.9 (p = 0.001). During the median follow-up of 33 months, 10 patients died, mainly from cardiac causes. Our experience indicates that the splenic and hepatic arteries provide useful alternatives to renal revascularization in selected circumstances with an acceptable rate of perioperative mortality and morbidity. The expected long-term survival in this group of patients is low.

Vascular expression of endothelial antigen PAL-E indicates absence of blood-ocular barriers in the normal eye

The endothelium-specific antigen PAL-E is expressed in capillaries and veins throughout the body with the exception of the brain, where the antigen is absent from anatomical sites with a patent blood-brain barrier. In this study we determined vascular endothelial staining for PAL-E in the normal eye in relation to the ocular blood-tissue barriers. Immunohistochemical staining of frozen tissue sections of eyes from 22 cornea donors and a number of normal animal autopsy eyes was performed for the PAL-E antigen and the blood-brain barrier marker glucose transporter 1. In normal human and animal eyes, endothelial PAL-E staining was absent from the microvasculature in iris, ciliary muscle, optic nerve and retina. In a few normal human eyes, some weakly stained capillaries were observed in the retina and nerve fiber layer, mostly in the peripapillary area. Marked staining of capillaries and venules with PAL-E was observed in the conjunctiva, episclera, sclera, ciliary processes, choriocapillaris and optic nerve head. In general, the endothelial antigen PAL-E is absent from microvessels involved in the blood-ocular and the blood-retinal barriers. PAL-E may therefore be a useful marker to identify pathological breakdown of blood-ocular barriers.

The role and resources required for the introduction of generic ward assistants using GRASP systems workload methodology: a quantitative study

Non-nursing workers have been advocated as a means of ameliorating high nursing utilizations, whether the cause be budgetary or the inability to recruit trained staff. The creation of a generic worker who would undertake domestic, catering and non-nursing activities has been seen as a way of improving the ward environment and releasing trained staff and health care assistants from non-nursing activities, GRASP systems workload methodology was used to develop a job description and a tool to quantify the resources needed to introduce such workers. A quantitative research study and activity analysis was carried out on two sample wards to validate the tool. The results were validated by a 'within study' audit process comparative analysis and an activity qualitative analysis using a Likert attitudinal scale. Empirical analysis of the study's findings and the financial consequences were predicted across the Trust.

Impact of high-dose salvage therapy (BEAM) on overall survival in younger patients with advanced large-cell lymphomas entered into BNLI trials

The survival of two cohorts of patients with stage III/IV large-cell lymphomas treated by CHOP has been compared. In the first cohort of 88 patients (1974-1982), high-dose therapy with autologous bone marrow transplantation (ABMT) was not available as salvage therapy and in the second cohort of 87 patients (1987-1992), this was the recommended salvage for patients with disease that was still chemosensitive to conventional-dose therapy. The actuarial overall survivals at five years were 40% and 44% in the first and second cohorts, respectively, indicating that the availability of ABMT had made little impact. Of the 62 patients in the second cohort who failed CHOP therapy, 8 died before second-line chemotherapy could be given, 1 refused more therapy, and 8 were considered unsuitable for further combination chemotherapy. Seven patients with localized disease remaining received local radiotherapy. Of the 38 patients given salvage therapy, 14 had chemoresistant disease. Only 9 patients received high-dose BEAM chemotherapy and ABMT, and 7 remain disease-free. ABMT was restricted to a highly select patient group, and as a result more widespread application of this strategy might result in only a modest further improvement.

Carbamazepine trial for Lesch-Nyhan self-mutilation

Anticonvulsants may reduce the self-mutilation of acquired sensory neuropathy, and one report described sensory neuropathy in an older patient with Lesch-Nyhan syndrome. We performed nerve and muscle biopsies on four patients with Lesch-Nyhan syndrome and initiated an uncontrolled pilot trial to see if carbamazepine would reduce the self-mutilation in these patients. All of the boys had clinical features typical of Lesch-Nyhan syndrome, and the diagnosis was confirmed in each by enzyme analysis. No specific abnormalities were identified in either nerve or muscle. Nevertheless, self-mutilation and the need for constant restraint diminished in all four patients, though in one the effect was only transient. Two patients had increased self-mutilation when carbamazepine was stopped, then improved a second time when treatment was restarted. Sensory neuropathy was not confirmed, so any effect of carbamazepine is likely to be on the central nervous system.