Soluble osteopontin inhibits apoptosis of adherent endothelial cells deprived of growth factors

Osteopontin (OPN) is primarily an extracellular glycosylated phosphoprotein capable of stimulating cell migration and cell attachment, predominantly to mineralized surfaces. Found in moderate levels in plasma, it acts as a cytokine able to modify gene expression via integrins and certain CD44 isoforms. In this work we show that soluble OPN inhibits apoptosis of adherent human umbilical vein endothelial cells incubated in medium lacking critical growth factors and cytokines. In a dose-dependent manner OPN reduced the formation of apoptotic bodies and suppressed DNA fragmentation. OPN also caused an increase in Bcl-X(L) mRNA levels, suppressed the apparent dispersion of Bcl-X(L) throughout the cytoplasm, and slightly enhanced IkappaB-alpha protein degradation. These data suggest that a function of OPN in homeostatic processes is to facilitate the survival of stressed endothelial cells, possibly by occupying unligated integrins and suppressing integrin-mediated death.

Engraftment syndrome in breast cancer patients after stem cell transplantation is associated with poor long-term survival

An autoaggression graft-versus-host (GVHD)-like syndrome or engraftment syndrome (ES) presenting with skin rash, fever, and other clinical findings can accompany the early phase of engraftment after autologous peripheral blood stem cell (PBSC)/bone marrow (BM) transplantation. Because ES was suggested to be analogous to GVHD, we have investigated whether ES was associated with any graft-versus-tumor effect that would affect disease progression and survival in breast cancer patients. Eighty-five consecutive patients who received BM/PBSC transplantation for breast cancer (stages II-IV) between July 1991 and July 1997 with minimum 2-year follow-up were studied. Median follow-up time was 892 days (range, 106-2913 days). Thirty-three patients (39%) developed ES. The incidence of relapse/progressive disease for the whole cohort was 61% and was similar in patients who developed ES compared with those who did not. However, there was an increased rate of mortality observed among the patients who had developed ES versus those who had not, although it was statistically not significant, (52% versus 31%, respectively; log rank, P = .08). Increased mortality rates due to disease progression were seen in all patients with ES regardless of their disease stage. In relapsed patients, median survival time after transplantation was 586 days for those with ES versus 847 days for those without ES, and the mortality rate was 85% (17/20) versus 51% (16/31) (P = .008) for those with or without ES, respectively. Visceral (lung, liver, brain, adrenal) or multiple-site relapses were observed in 85% of patients with ES versus 52% without ES (P = .01). In conclusion, whereas there was no effect of ES on relapse rate, a surprisingly significant increase in disease-related mortality rates among relapsed breast cancer patients with ES was found. Thus, patients with ES should be considered for close follow-up and further therapy posttransplantation.

Detection and characterization of erythromycin-resistant methylase genes in Gram-positive bacteria isolated from poultry litter

The epidemiology of four erythromycin-resistant methylase ( erm) genes, ermA, ermB, ermC and msrA, was determined in erythromycin-resistant staphylococci, enterococci and streptococci isolated from poultry litter. All isolates were resistant to multiple antibiotics. Southern hybridization indicated that 4 of the 20 staphylococci contained the ermC gene on plasmids: on a 2.2 kb plasmid in Staphylococcus hominis and S. sciuri, on a 6.0 kb plasmid in S. xylosus, and on a 7.0 kb plasmid in S. lentus. In 16 of the 20 staphylococci, the ermA gene was harbored exclusively on the chromosome, as a double chromosomal insert on 8.0 and 6.2 kb EcoRI fragments. None of the staphylococci harbored the msrA gene. Dot-blot analysis indicated that all enterococci and streptococci hybridized with a biotinylated ermB gene probe. Southern hybridization indicated that only 2 of the 19 erythromycin-resistant enterococci contained the ermB gene on plasmids. The gene was localized on 4.0 kb and 5.9 kb plasmids, respectively, in two Enterococcus faecium isolates. Results from our studies indicate that the patterns of occurrence of erm genes, the sizes of the plasmids and the copy numbers of the inserts were different from the existing information on the presence of erm genes in clinical strains of Staphylococcus spp.

Type-specific antibodies to the platelet-derived growth factor receptors: role in elucidating the structural and functional characteristics of receptor types

Two types of platelet-derived growth factor receptors have been cloned and sequenced. Both are glycoproteins with similar molecular weights. We have earlier established the ligand binding specificity, ligand-induced dimerization, and kinase activation of these two receptor types [Bishayee et al. (1989) J. Biol. Chem. 264, 11699-11705; Kanakaraj et al. (1991) Biochemistry 30, 1761-1767]. In the present studies, we have investigated the biosynthesis, processing, and glycosylation of the alpha-receptor and compared its structural and functional characteristics to those of the beta-receptor. Unlike an anti-peptide antibody, AbP2 (amino acid residues 964-979), to the human beta-receptor which detects a phosphorylation-specific conformation of the receptor, an antibody, AbP alpha 2 (amino acid residues 956-971), to the corresponding region of the human alpha-receptor failed to do so. However, our studies revealed that the stability of the alpha-receptor is comparable to that of the beta-receptor. In addition, N-linked glycosylation of the alpha-receptor, like that of the beta-receptor, is not important in kinase activation. We have exploited the lack of an effect of N-linked oligosaccharides on the functioning of the alpha-receptor to develop a simple and rapid method for direct demonstration of ligand-induced noncovalently linked alpha-beta-receptor heterodimer formation. This method is based on the interaction between functionally active short and the long forms of two receptor types which can be resolved by denaturing gel electrophoresis.

Dislocation of the elbow with intra-articular entrapment of the medial epicondyle in adults. Report of two cases

Intra-articular entrapment of the medial epicondyle with dislocation of the elbow is a common injury pattern in childhood. The occurrence of this injury is extremely rare in adults. We present two cases of dislocation of the elbow with intra-articular inclusion of the medial epicondyle in adult patients. One case was treated by closed reduction and the other required open reduction. A brief review of the scanty literature on the subject is also presented. The case reports highlight the need for early diagnosis and management of these atypical cases in adults.

Triggered enzymatic degradation of a water-soluble polymer solution using a novel inhibitor

Controlled enzymatic degradation of solutions of guar galactomannan, a naturally occurring polysaccharide, offers a powerful tool to enhance its usage in a variety of applications. In this study, we use viscometry to investigate the use of tris(hydroxymethyl)aminomethane (Tris) as a reversible, pH-dependent inhibitor to control the degradation of guar galactomannan by Aspergillus niger beta-mannanase. Viscosity measurements of pH 9 guar solutions containing 25 mM Tris show no reduction in the viscosity when treated with beta-mannanase. In contrast, samples containing no Tris show significant reduction in viscosity within an hour. Samples maintained at a pH of 9 in the presence of Tris for several hours show no change in viscosity; however, reduction of the pH of the sample to 4 initiates enzymatic degradation of the guar solution resulting in a rapid reduction in solution viscosity. This reversible, pH-dependent inhibition is possibly a result of the protonation state of Tris as well as key amino acids in the active site.

Infection and mucosal injury in cancer treatment

The oral and gastrointestinal mucosa acts as an important mechanical barrier that prevents local or systemic invasion by microorganisms. Cytotoxic chemotherapy-induced mucosal injury (MI) of oral cavity and intestinal epithelium occurs in many patients treated for malignancy. Compromise of the mucosal barrier can contribute to local invasion by colonizing microorganisms and, subsequently, to systemic infection. Historically, gram-negative bacteremia has been the most problematic bacterial infection in neutropenic patients, but its incidence has reduced over time because of the use of prophylactic antibiotics. There has been a shift in the type of infecting organisms responsible for bacteremia in these patients, from predominantly gram-negative organisms to gram-positive cocci. The viridans group of streptococci is composed of the most frequent bacterial pathogens associated with MI. When speciated, oral colonizers such as Streptococcus mitis, Streptococcus oralis, and Streptococcus sangulis II are the most frequently identified pathogens. Other systemic infections caused by vancomycin-resistant enterococci, Stenotrophomonas maltophilia, and Candida species have also been associated with MI after cancer treatment. Infection can also exacerbate MI after cancer treatment. The best recognized example is herpes simplex virus type 1 (HSV-1). Latent virus is frequently reactivated in HSV-seropositive patients; this reactivation leads to stomatitis, which can be indistinguishable from MI caused by cytoreductive therapies. Antiviral prophylaxis or treatment can control the virus-induced MI and bring about overall amelioration of MI. Recognition of this infectious cause of MI is important in order for clinicians to anticipate and minimize oral toxicity and to facilitate optimal delivery of the antineoplastic regimen.

Late onset of invasive aspergillus infection in bone marrow transplant patients at a university hospital

Despite new antifungal treatment strategies, invasive aspergillosis (IA) remains a principal cause of infectious mortality after bone marrow transplantation (BMT). We reviewed the medical records of 93 allogeneic and 149 autologous transplant recipients during a 20 month period, with attention to cases of proven or probable IA. No autologous transplant recipient developed IA, whereas IA was seen in 15.1% of allogeneic recipients (including two of five patients with a prior history of IA despite prophylaxis), for an overall incidence of 5.8%. The median time to occurrence was 92 days post transplant, with no de novo cases developing prior to engraftment. Survival 100 days from diagnosis was 29%. Risk factors for the development of IA included > or = 21 days of corticosteroid therapy of >or= 1mg/kg/day and post-transplant cytomegalovirus (CMV) infection. These two risk factors were statistically linked. Our data illustrate a shift toward a later occurrence of post-transplant IA, suggesting a need for close, prolonged surveillance in the outpatient environment. The contributory role of protracted corticosteroid use is also highlighted. These data have important implications in an era of alternate donor transplants and more intense immunosuppression. Established strategies implementing newer, less toxic antifungal agents as prophylaxis in high-risk patients are needed.

Epicardial haematoma: rare cause of acute myocardial ischaemia

Pericardial effusion and coronary dissection are well known complications of percutaneous transluminal coronary angioplasty (PTCA). We report a rare case of sub-epicardial haematoma after PTCA, leading to local compression and cardiogenic shock. We discuss the successful management of this problem.

Identification of predominant human and animal anaerobic intestinal bacterial species by terminal restriction fragment patterns (TRFPs): a rapid, PCR-based method

Identification of predominant human and animal intestinal tract anaerobes by conventional methods is cumbersome, time-consuming and less sensitive as compared to molecular methods. We have developed a molecular technique to identify most of the abundant intestinal microflora by polyermase chain reaction (PCR) amplification of a 16S rRNA gene fragment using a pair of universal PCR primers. The forward PCR primer was labelled with 6-carboxyfluorescein amino hexy (6-FAM) fluorescent dye to detect the terminal fragment of the PCR products after digestion with restriction enzymes. The PCR products were purified and digested with restriction enzymes and were analysed by capillary electrophoresis using an automated DNA sequencer. The data was analysed with GeneScan software 2.1. Eleven bacteria (Eubacterium biforme, E. limosum, Peptostreptococcus productus, Lactobacillus acidophilus, Bacteroides thetaiotaomicron, B. vulgatus, B. distasonis, Clostridium clostridiiforme, C. leptum, C. perfringens and Escherichia coli) that are predominant in human and animal intestinal tract were successfully identified by this rapid molecular technique. This protocol is rapid, accurate, sensitive and capable of identifying multiple organisms in a single sample.

The application of controlled intracranial hypertension in slit ventricle syndrome patients with obstructive hydrocephalus and shunt malfunction

When a shunted patient with slit-ventricle syndrome (SVS) presents with a shunt malfunction or infection, the third ventricle may not be of sufficient caliber, despite the shunt malfunction, to allow atraumatic passage of an endoscope to the floor of the third ventricle. We describe four slit ventricle syndrome patients with respectively 24, 12, 18 and 2 prior shunt revisions who presented with shunt infection. In each patient the shunt was externalized and controlled intracranial hypertension (CIH) was applied over an average of 5.8 days by raising the height of the external ventricular drain (EVD) bag to a mean height of 18.8 cm above EAM. This increased the mean transverse third ventricular diameter from an average of 0.28 cm on admission to 1.13 cm after application of CIH. Endoscopic third ventriculocisternostomy (ETV) was satisfactorily performed in three of the four patients who remain shunt free after a mean follow-up of 21.3 months. CIH followed by ETV is an option in selected SVS patients who present with shunt malfunction or infection.

Ductal lavage for detection of cellular atypia in women at high risk for breast cancer

BACKGROUND

Breast cancer originates in breast epithelium and is associated with progressive molecular and morphologic changes. Women with atypical breast ductal epithelial cells have an increased relative risk of breast cancer. In this study, ductal lavage, a new procedure for collecting ductal cells with a microcatheter, was compared with nipple aspiration with regard to safety, tolerability, and the ability to detect abnormal breast epithelial cells.

METHODS

Women at high risk for breast cancer who had nonsuspicious mammograms and clinical breast examinations underwent nipple aspiration followed by lavage of fluid-yielding ducts. All statistical tests were two-sided.

RESULTS

The 507 women enrolled included 291 (57%) with a history of breast cancer and 199 (39%) with a 5-year Gail risk for breast cancer of 1.7% or more. Nipple aspirate fluid (NAF) samples were evaluated cytologically for 417 women, and ductal lavage samples were evaluated for 383 women. Adequate samples for diagnosis were collected from 111 (27%) and 299 (78%) women, respectively. A median of 13,500 epithelial cells per duct (range, 43-492,000 cells) was collected by ductal lavage compared with a median of 120 epithelial cells per breast (range, 10-74,300) collected by nipple aspiration. For ductal lavage, 92 (24%) subjects had abnormal cells that were mildly (17%) or markedly (6%) atypical or malignant (<1%). For NAF, corresponding percentages were 6%, 3%, and fewer than 1%. Ductal lavage detected abnormal intraductal breast cells 3.2 times more often than nipple aspiration (79 versus 25 breasts; McNemar's test, P<.001). No serious procedure-related adverse events were reported.

CONCLUSIONS

Large numbers of ductal cells can be collected by ductal lavage to detect atypical cellular changes within the breast. Ductal lavage is a safe and well-tolerated procedure and is a more sensitive method of detecting cellular atypia than nipple aspiration.

Medical surfing

The Internet has revolutionized information technology. Vast amounts of latest information are available on the Internet to medical professionals. Medical surfing is fast becoming part of a doctor's profession. But the way to approach the Internet and retrieve useful information from myriads of medical websites seems a daunting task to many. This review aims to help the newcomer, the medical students and doctors in obtaining fruitful medical information while surfing. It will prevent them from the feeling of getting drowned in the ocean of medical information. As medical information is not restricted to books and journals, providing Internet addresses of different medical bodies with few salient features, will go a long way in helping attain the required information without wasting time. The Internet will soon become a universal library. Medical surfing should be included in the curriculum of all medical schools and universities.

Regulation of human papillomavirus type 1 replication by the viral E2 protein

The E1 and E2 proteins encoded by papillomaviruses are required for viral replication. Earlier studies have shown that the viral E2 protein plays an important role in replication by targeting the E1 helicase to the origin of replication (ori). We have previously shown that the E1 protein of human papillomavirus (HPV) type 1 is sufficient for the in vivo replication of ori plasmids, although the E2 protein stimulates replication. In this study, we have further analyzed the role of the E2 protein in HPV-1 replication. The optimal ori of HPV-1 contains one putative E1 binding site (E1BS) and two putative E2 binding sites, E2BS-3 and E2BS-4. Plasmid pori171, containing the optimal ori, replicates to much higher levels than plasmid pori312, which includes an additional upstream E2 binding site, E2BS-2, located 75 nucleotides upstream of E2BS-3. To study the possible role of E2BS-2 and other upstream sequences in E2-dependent downregulation of replication, transient replication analysis was done in the presence of increasing levels of the E2 protein. Interestingly, inhibition of pori312 replication was more severe at higher levels of E2, suggesting that this protein may also negatively regulate HPV-1 replication. Deletion of sequences from pori312 containing an additional putative E2BS, E2BS-2A, relieved the repression of replication to a significant extent, while replacement of E2BS-2 with a different sequence of the same length had a modest effect. These results suggest that E2BS-2A plays a major and E2BS-2 a minor role in the negative regulation of HPV-1 replication at high E2 levels. Electrophoretic mobility-shift assays showed that the purified E2 protein bound with high affinity to E2BS-3 and weakly to the other putative E2BSs located within the viral long control region. EMSA using various ori fragments showed the formation of multiple E2-DNA complexes which likely represent binding of E2 to multiple E2BSs present within the HPV-1 ori. Our data are consistent with the assembly of ori-protein complexes at high E2 levels that are impaired for replication and further suggest that E2 may regulate HPV-1 replication by a mechanism involving interaction between the E2 protein bound to E2BSs at a distance.

Hepatoprotective activity of Luffa echinata fruits

The different extracts of the fruits of Luffa echinata Roxb. (Cucurbitaceae) were tested for their hepatoprotective activity against CCl(4) induced hepatotoxicity in albino rats. The degree of protection was measured by using biochemical parameters like serum glutamic oxalacetic transaminase (SGOT), serum glutamic pyruvate transaminase (SGPT), alkaline phosphatase (ALKP), total protein (TP) and total albumin (TA). The petroleum ether, acetone and methanolic extracts showed a significant hepatoprotective activity comparable with those of Silymarin.

Increase in mortality rates from intrahepatic cholangiocarcinoma in England and Wales 1968-1998

BACKGROUND

The age standardised mortality rate per 100 000 population for all causes of liver tumours (International Classification of Disease 9 (ICD-9) 155) has almost doubled in England and Wales during the period 1979-1996. We further analysed the mortality statistics to determine which anatomical subcategories were involved.

METHODS

Mortality statistics for liver tumours of ICD-9 155, 156, and subcategories, and for tumours of the pancreas (ICD-9 157), in England and Wales were investigated from the Office for National Statistics, London, from 1968 to 1996 inclusive. Data for 1997 and 1998 were also available on intrahepatic cholangiocarcinomas.

RESULTS

There has been a marked rise in age standardised mortality rates for intrahepatic cholangiocarcinoma. Since 1993, it represents the commonest recorded cause of liver tumour related death in England and Wales. This is evident in age groups older than 45 years. In contrast, mortality trends from other primary liver tumours, including hepatocellular carcinoma, were unremarkable.

CONCLUSIONS

The observed increase in mortality from intrahepatic cholangiocarcinoma may represent better case ascertainment and diagnosis due to improved diagnostic imaging, use of image guided biopsies, or increased use of ERCP. However, the trend started before ERCP was introduced nationally, mortality rates have continued to increase steadily thereafter, and there is no clear evidence that diagnostic transfers easily explains the findings. Alternatively, these observations may represent a true increase in intrahepatic bile duct tumours. Epidemiological studies are required to determine whether there is any geographical clustering of cases around the UK.

Osteoporosis Follow-up After Wrist Fractures Following Minor Trauma

BACKGROUND

Patients presenting with low-trauma wrist fractures are an ideal target population for early case finding of osteoporosis. We decided to investigate whether this early detection occurred in practice.

METHODS

This study was conducted at a single center in Edmonton, Alberta. A structured interview format was used to contact 112 (72%) of 156 patients older than 40 years who were diagnosed as having an atraumatic fracture of the distal radius/ulna from April 1997 to March 1998 and from January 1999 to February 1999. Information on osteoporosis follow-up and drug therapy was obtained from the patient.

RESULTS

The time between fracture and telephone interview ranged from 6 months to 3 years, with the majority of the sample being interviewed at least 1 year after fracture. Of the 112 patients in this study, 44 had sustained previous fractures, 17 of which had occurred at the wrist, vertebrae, or hip. Sixteen patients in the sample had already sustained a subsequent clinical fracture before our telephone contact. Thirty-two patients had received treatment for osteoporosis before fracture. A further 24 patients (21%) had undergone osteoporosis follow-up after fracture. After fracture, 42 (38%) of all patients were receiving either hormone replacement therapy or using a bisphosphonate.

CONCLUSIONS

Only 50% of the study population had received osteoporosis follow-up after fracture. Few patients had any change in their medication use after fracture. The findings in this study population suggest that recognition of the potential for osteoporosis in such patients is inadequate. Given the magnitude of this public health care problem, it is clear that attention to case finding and treatment of osteoporosis should be increased.