Airway proteins involved in bacterial clearance susceptible to cathepsin G proteolysis.

Serine proteases released from neutrophils are central to the pathogenesis of cystic fibrosis lung disease and are considered to be obvious therapeutic targets. Neutrophil elastase digests key opsonins present in the lung and disrupts phagocytosis, allowing bacteria to persist despite established pulmonary inflammation. We have found that cathepsin G, an abundant serine protease found in human and murine neutrophils, has other roles in the development of suppurative lung diseases. Murine models of endobronchial inflammation indicate that cathepsin G inhibits airway defences and interferes with the host's ability to clear Pseudomonas aeruginosa from the lung with effects distinct from neutrophil elastase. We hypothesise that differences in bacterial killing are due to defects in innate defences created by proteolysis. Protein profiles of bronchoalveolar lavage of infected wild-type and cathepsin G-deficient mice were compared using two-dimensional polyacrylamide gel electrophoresis and tandem mass spectrometry. Four proteins in bronchoalveolar lavage were cleaved by cathepsin G. Serum amyloid P component leaked into the lung during acute infection and was digested by cathepsin G. Its cleavage products had greater binding to lipopolysaccharide and interfered with phagocytosis. These results indicate that cleaved serum amyloid P component acts as an anti-opsonin and interferes with bacterial clearance from the lung.

Fasciola hepatica in UK horses.

BACKGROUND: Fasciola hepatica (liver fluke) affects grazing animals including horses but the extent to which it affects UK horses is unknown. OBJECTIVES: To define how liver fluke affects the UK horse population. STUDY DESIGN: Descriptive, cross-sectional, observational study. METHODS: An F. hepatica excretory-secretory antibody detection ELISA with a diagnostic sensitivity of 71% and specificity of 97% was validated and used to analyse serum samples. An abattoir study was performed to determine prevalence. A case-control study of 269 horses compared fluke exposure between horses with liver disease and controls. Data on clinical signs and blood test results were collected for sero-positive horses. Genotyping of adult fluke was used to produce a multilocus genotype for each parasite. RESULTS: Four (2.2%) of 183 horses registered in the UK, sampled in the abattoir, had adult flukes in the liver, and the sero-prevalence of F. hepatica was estimated as 8.7%. In the case-control study, horses showing signs consistent with liver disease had significantly higher odds of testing positive for F. hepatica on ELISA than control horses. In 23 sero-positive horses, a range of non-specific clinical signs and blood test abnormalities was reported, with a third of the horses showing no signs. Genotypic analysis of liver flukes from horses provided evidence that these came from the same population as flukes from sheep and cattle. MAIN LIMITATIONS: Bias could have arisen in the prevalence and case-control studies due to convenience sampling methods, in particular the geographic origin of the horses. Only a small number of horses tested positive so the data on clinical signs are limited. CONCLUSIONS: Exposure to liver fluke occurs frequently in horses and may be an under-recognised cause of liver disease. Flukes isolated from horses are from the same population as those found in ruminants. When designing and implementing parasite control plans, fluke should be considered, and horses should be tested if appropriate.

BRCA1 and GADD45 mediated G2/M cell cycle arrest in response to antimicrotubule agents.

BRCA1 is a tumour suppressor gene implicated in the predisposition to early onset breast and ovarian cancer. We have generated cell lines with inducible expression of BRCA1 to evaluate its role in mediating the cellular response to various chemotherapeutic drugs commonly used in the treatment of breast and ovarian cancer. Induction of BRCA1 in the presence of Taxol and Vincristine resulted in a dramatic increase in cell death; an effect that was preceded by an acute arrest at the G2/M phase of the cell cycle and which correlated with BRCA1 mediated induction of GADD45. A proportion of the arrested cells were blocked in mitosis suggesting activation of both a G2 and a mitotic spindle checkpoint. In contrast, no specific interaction was observed between BRCA1 induction and treatment of cells with a range of DNA damaging agents including Cisplatin and Adriamycin. Inducible expression of GADD45 in the presence of Taxol induced both G2 and mitotic arrest in these cells consistent with a role for GADD45 in contributing to these effects. Our results support a role for both BRCA1 and GADD45 in selectively regulating a G2/M checkpoint in response to antimicrotubule agents and raise the possibility that their expression levels in cells may contribute to the toxicity observed with these compounds.

Recanalization of Chronically Occluded Aortocoronary Saphenous Vein Bypass Grafts With Long-Term, Low Dose Direct Infusion of Urokinase (ROBUST): a serial trial.

OBJECTIVES: This multicenter study sought to evaluate the short-term efficacy and safety of prolonged, low dose, direct urokinase infusion in recanalization of chronically occluded saphenous vein bypass grafts in a large sample of patients, as well as to determine the 6-month patency rates for this procedure. BACKGROUND: Patients with chronically occluded aortocoronary vein grafts and uncontrolled angina pectoris have limited options for therapy. Previous work has shown that chronically occluded vein grafts can be recanalized by thrombolysis. METHODS: A coaxial infusion of urokinase (100,000 U/h) was given directly into occluded vein grafts in 107 patients. Balloon angioplasty was performed after lysis was achieved. Patients were discharged with warfarin and aspirin therapy. Six-month clinical follow-up data were obtained, and repeat angiography was encouraged. RESULTS: Initial patency was achieved in 74 patients (69%). Mean duration of infusion was 25.4 h, and mean urokinase dosage was 3.70 million U. Acute adverse events included acute myocardial infarction in 5 patients (5%), enzyme level elevation in 18 (17%), emergency coronary artery bypass graft surgery in 4 (4%), stroke in 3 (3%) and death in 7 (6.5%). Recanalization was unsuccessful in all seven patients who died. Six-month follow-up angiograms were obtained for 40 patients (54%), 16 of whom maintained a patent graft (40%). Angina was present in 13 patients with successful (22%) and 12 with unsuccessful (71%) recanalization at 6-month follow-up. CONCLUSIONS: Chronically occluded aortocoronary vein grafts can be recanalized in approximately 70% of appropriately selected patients. Complications are similar to those observed with repeat operations. Clinical follow-up shows an improvement in angina. This procedure is intended for patients with only one occluded vein graft. Strict adherence to the protocol will improve patency and reduce complications.

Correlation of EEG, computerized tomography, and clinical findings. Study of 100 patients with focal delta activity.

One hundred consecutive patients with continuous, focal, polymorphic delta activity on EEG who were also studied by computerized cranial tomography (CT) were reviewed. Sixty-eight percent showed focal structural lesions on CT, with stroke being the most frequent etiologic factor. Tumors occurred less often and trauma more frequently than in previous studies. Convulsions were the most frequent cause of focal delta activity with a normal scan.

Chorea: a late complication of a subdural hematoma.

Subdural hematoma has rarely been implicated as a cause of chorea. We describe a case of chorea occurring several months after evacuation of a traumatic subdural hematoma. No other causes of chorea were found. In this case and one previously reported case, signs of tentorial herniation were present prior to surgery. Herniation may damage the basal ganglia, with resultant chorea.

Diabetic oculomotor paresis with pupil fixed to light.

The pupillary near response should always be evaluated when the light response is defective. We present a case of diabetic third-nerve paresis with concomitant light-near dissociation. Without careful evaluation of the near response, angiography would have been indicated to rule out a posterior communicating artery aneurysm. Pharmacologic and slit lamp testing can be used to verify light-near dissociation.

Peptide mapping on Northern blot analyses of insulin receptors in brain and adipocytes.

Previous studies have demonstrated differences in the size of insulin receptor subunits in brain and adipocytes that appear to involve variations in glycosylation of the proteins. In this report, we examined the degree of homology in the protein backbones of insulin receptors in both tissues by peptide mapping and compared the mRNAs encoding the receptors by Northern blot analysis. Photoaffinity-labeled insulin receptors from rat brain and adipocytes were deglycosylated and then subjected to partial proteolysis by five different enzymes with differing substrate specificities. The intact receptors and their proteolytic fragments were analyzed by electrophoresis and autoradiography. Each enzyme yielded a unique pattern of fragments ranging from 70 to 11 kDa. In all cases, there was a striking similarity in the peptide maps generated from insulin receptors in brain and adipocytes. Northern hybridization experiments were carried out using poly(A)+ RNA from rat brain, rat adipocytes, and human hepatocarcinoma (HEP G2) cells. In rat brain, two bands of 9.5 and 7.4 kb were detected and, in rat adipocytes, the same two bands were observed. The two mRNA bands observed in rat tissues represented only two of the five mRNA species seen in human HEP G2 cells. The results indicate that the protein domains and the mRNAs encoding of insulin receptors in brain and adipocytes are very similar, if not identical.

Evidence for a subtype of insulin-like growth factor I receptor in brain.

We examined the structure of receptors for insulin-like growth factor I (IGF-I), insulin, and epidermal growth factor (EGF) in human brain and human placenta using affinity cross-linking procedures and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. In human brain, proteins specifically cross-linked to 125I-IGF-I, 125I-insulin, and 125I-EGF had apparent molecular weights of 120,000, 115,000 and 170,000, respectively. In human placenta, proteins cross-linked to 125I-IGF-I and 125I-insulin were 10 kDa larger than the corresponding subunits in brain. The receptor labeled by 125I-EGF in placenta was indistinguishable from the EGF receptor in brain. The size discrepancy of IGF-I receptors in brain and placenta was no longer apparent after removing the carbohydrate moieties of the proteins with endo-beta-N-acetylglucosaminidase F (EndoF). Furthermore, the brain IGF-I receptor was not cleaved by neuraminidase, whereas, the placental IGF-I receptor had increased mobility on SDS gels following neuraminidase treatment. The results indicate that receptors for IGF-I and insulin in human brain are structurally distinct from the corresponding receptors in human placenta, the structural heterogeneity of the receptors involves differences in N-linked glycosylation, particularly the terminal processing steps, and EGF receptors are present in human brain and human placenta but are structurally similar in these tissues. We conclude that there is a selective modification in the glycosylation of receptors for IGF-I and insulin in brain.

Single site experience with high-speed coronary rotational atherectomy.

This report describes a single site experience as part of a multicenter clinical trial with high-speed rotational atherectomy in human coronary arteries. A total of 108 patients with 143 lesions had interventions, were grouped by success or failure, and were analyzed by patient, lesion, and procedural variables. Satisfactory results were achieved in 131 of 143 lesions (92%) and 99 of 108 (92%) patients. Neither patient-related variables (age, gender, diabetes, hypertension, cigarette use, restenosis, previous myocardial infarction, and left ventricular function) nor lesion characteristics (length, ostial or bifurcation location, calcification, lesion classification, and coronary location) were predictive of poor outcome. Tears, acute closure, percentage stenosis after rotational atherectomy and after adjunctive balloon angioplasty were the procedural variables that were statistically associated with outcome by univariate methods. Multivariate analysis isolated postintervention residual stenosis as the only variable that was statistically different between groups. Serious complications included one death in the catheterization laboratory, one Q-wave myocardial infarction, three non-Q myocardial infarctions, and three emergency coronary bypass operations for sustained vessel closure. One patient required emergency surgery for a pacing wire perforation not related to the use of the device. The potential benefits of high-speed rotational atherectomy include increased safety in complex lesions, the ability to address lesions not amenable to balloon techniques, and the possibility of reducing the incidence of restenosis.

Colposcopic biopsies versus loop electrosurgical excision procedure cone histology in human immunodeficiency virus-positive women.

OBJECTIVE: To compare the discrepancy between colposcopically directed punch biopsy and excisional cone biopsy in human immunodeficiency-positive (HIV+) vs. HIV-negative (HIV-) women. STUDY DESIGN: We performed a case-control analysis of women treated with excisional cone biopsy after an abnormal colposcopic punch biopsy. Punch and cone biopsy histology were compared in 29 HIV+ (mean CD4 = 251 cells/mm3, 10 with the acquired immunodeficiency syndrome) and 31 HIV- women. Only patients with no prior treatment for cervical dysplasia, satisfactory colposcopy and cervical cytologic smears concordant with colposcopic biopsies were included. RESULTS: Disagreement between punch biopsy and cone histology was evident in 41% (12/29) of HIV+ patients and 48% (15/31) of seronegative women (chi 2, P = .78). The cone specimen had a higher grade lesion than the punch biopsy in 38% (11/29) of HIV+ patients and 32% (10/31) of seronegative women (P = .65). Overall, patients with HPV, cervical intraepithelial neoplasia (CIN) I or II on punch biopsy had CIN III on 30% of cone biopsies (5/23 HIV+ vs. 9/23 HIV-women, P = .2). In HIV+ women with HPV or CIN I on punch biopsy, 50% (9/18, 95% confidence interval 26-74%) had CIN II or III on the excisional cone vs. 18% (2/11) HIV-patients (Fisher's test, P = .13). However, in HIV+ patients with CIN II or III on cone biopsy, 47% (9/19) had only CIN I or human papillomavirus on punch biopsy as compared to 9% (2/22) HIV-patients (chi 2, P = .01). CONCLUSION: Colposcopically directed punch biopsies are poor predictors of cone histology in both HIV+ and HIV-patients. Based on confidence intervals, at least 26% and as many as 74% of HIV+ women with CIN I on punch biopsy may have a significantly worse lesion on cone biopsy despite satisfactory colposcopy. Though CIN I may be observed in immunocompetent women, due to the likelihood of a more advanced lesion, observation may not be justified in HIV+ women.

Students' rights in a public institution.

This article describes the differences in public and private institutions, and how faculty knowing the differences can determine the rights to which students are entitled. It further provides cases to demonstrate the rights that nursing students have in a public institution.

National review of urology outpatient practice in the UK.

OBJECTIVE: To audit the current UK outpatient workload and compare this to the national standards as set out by the British Association of Urological Surgeons (BAUS) in A Quality Urological Service for Patients in the New Millennium published in October 2000. PARTICIPANTS: 520 UK (NHS) and 21 Republic of Ireland (non-NHS) consultant urologists registered with BAUS in 2000. MAIN OUTCOME MEASURES: Extent to which consultant urologists are able to comply with guidelines set out by their specialist association, the BAUS and by the Royal College of Surgeons of England. RESULTS: The questionnaire return rate was 61% (318/520; regional range 42%-75%). The median "routine" clinics/week was two (1-5) with a mean of 13 (1-40) new and 26 (7-80) follow ups. Fifteen percent (49/318) of consultants worked alone in clinic; of the remainder assistance included specialist registrar 67% (212/318), staff grade/associate specialist 32% (102/318), senior house officer 53% (172/318), and pre-registration house officer 2% (7/318). Only 21% (66/318; regional range 0%-46%) of responding consultants followed the BAUS recommendations for outpatient workload/manpower. CONCLUSIONS: A minority of consultants are able to adhere to the outpatient workload guidelines as set out by BAUS council in 2000. In addition, there appears to be significant variations within and between training regions. Development of this project into a regional audit tool may allow intraregional guideline formation governing hospital outpatient workload.

Angiodysplasia of the upper gastrointestinal tract.

I have reviewed the English language literature on angiodysplasia of the upper gastrointestinal tract. Angiodysplasia is a distinct mucosal vascular lesion associated with acute or chronic gastrointestinal bleeding. Its etiology is unknown, but theories of its pathogenesis have evolved from its similarity to colonic angiodysplasia and an association with renal failure. Despite recurrent gastrointestinal bleeding, the endoscopic diagnosis is difficult because the lesions are so small and so similar to fresh blood. Endoscopic ablation by electrocautery or laser photocoagulation can reduce bleeding or make it stop, but repeated treatments are often necessary.

An unusual case of Reiter's disease.

A 72-year-old man was admitted to hospital after a syncopal attack. Investigations showed anaemia and adenocarcinoma of the colon. After tumour resection with end to end anastomosis he had a urinary catheter in situ for two days, but otherwise his recovery was unremarkable, until 13 weeks after operation when he developed classical Reiter's disease. Investigations did not reveal any known trigger factor but it is postulated that the process may have been initiated by urinary catheterisation or bowel surgery.

Structural and functional characteristics of insulin receptors in rat neuroblastoma cells.

Insulin receptors were detected in a variety of rat neuroblastoma and glioma cell lines. The binding of 125I-insulin to B103 neuroblastoma cells had characteristics typical of insulin receptors in other tissues, including high affinity for insulin, low affinity for insulin-like growth factor I (IGF-I), and curvilinear Scatchard plots. Using photoaffinity labeling procedures and sodium dodecyl sulfate (SDS) gel electrophoresis to analyze the subunit structure of insulin receptors in B103 cells, the predominantly labeled protein had an apparent molecular weight of 125K and the mobility of this protein was shifted after removal of sialic acid residues. On the basis of size and susceptibility to neuraminidase, the insulin binding subunit in neuroblastoma cells was identical to the alpha-subunit of insulin receptors in adipocytes and different from the 115K subunit found in brain. The presence of an "adipocyte" form of the insulin receptor in clonal cells derived from brain is probably a consequence of transformation and results from more extensive oligosaccharide processing of the 115K receptor expressed in normal brain cells. The fully glycosylated receptors in neuroblastoma cells were capable of exerting functions typical of insulin receptors in adipocytes such as internalization of insulin and stimulation of glucose transport.

Functional properties of the subtype of insulin receptor found on neurons.

In this report, we have examined the structure, regulation, and function of insulin receptors in cultured neurons from fetal chicken brain. The apparent molecular weight of the alpha-subunit of neuronal insulin receptors, analyzed by photoaffinity labeling and sodium dodecyl sulfate gel electrophoresis under reducing conditions, was 115,000. The number of insulin receptors in the cultures increased from day 2 to day 4 during a period of extensive process formation. After 5 days in culture, there were approximately 40,000 high-affinity insulin receptors per neuron. When neurons were photoaffinity labeled at 16 degrees C and then warmed to 37 degrees C for 30 min, approximately 40% of the cell-surface receptors were recovered in the intracellular, trypsin-insensitive pool. Chronic exposure of neurons to insulin (100 ng/ml) resulted in a time-dependent loss of neuronal insulin receptors with a maximal decrease of 50% after 24 h. Insulin had no effect on glucose transport, glucose oxidation, or glycogen synthase activity in neurons. On the other hand, insulin supported the growth and differentiation of a fraction of neurons isolated from chick forebrain. We conclude that (1) cultured neurons from fetal chicken brain express the same subtype of insulin receptor previously identified in adult rat and human brain, (2) the neuronal subtype of insulin receptor undergoes internalization and down-regulation in response to insulin, and (3) neuronal insulin receptors do not acutely regulate glucose metabolism but mediate growth in neurons.

Rotational atherectomy in anomalous coronary arteries.

We describe two cases of high speed rotational atherectomy performed in patients with anomalous coronary anatomy. These procedures are performed with standard equipment requiring no modifications using a percutaneous femoral approach. We feel these cases clearly illustrate the facile application of this new technology to unusual anatomical situations.