Active galaxies. A fast and long-lived outflow from the supermassive black hole in NGC 5548.

Supermassive black holes in the nuclei of active galaxies expel large amounts of matter through powerful winds of ionized gas. The archetypal active galaxy NGC 5548 has been studied for decades, and high-resolution x-ray and ultraviolet (UV) observations have previously shown a persistent ionized outflow. An observing campaign in 2013 with six space observatories shows the nucleus to be obscured by a long-lasting, clumpy stream of ionized gas not seen before. It blocks 90% of the soft x-ray emission and causes simultaneous deep, broad UV absorption troughs. The outflow velocities of this gas are up to five times faster than those in the persistent outflow, and, at a distance of only a few light days from the nucleus, it may likely originate from the accretion disk.

An attenuated Salmonella enterica serovar Typhimurium strain lacking the ZnuABC transporter induces protection in a mouse intestinal model of Salmonella infection.

Salmonella enterica serovar Typhimurium has long been recognised as a zoonotic pathogen of economic significance in animals and humans. Attempts to protect humans and livestock may be based on immunization with vaccines aimed to induce a protective response. We recently demonstrated that the oral administration of a Salmonella enterica serovar Typhimurium strain unable to synthesize the zinc transporter ZnuABC is able to protect mice against systemic salmonellosis induced by a virulent homologous challenge. This finding suggested that this mutant strain could represent an interesting candidate vaccine for mucosal delivery. In this study, the protective effect of this Salmonella strain was tested in a streptomycin-pretreated mouse model of salmonellosis that is distinguished by the capability of evoking typhlitis and colitis. The here reported results demonstrate that mice immunized with Salmonella enterica serovar Typhimurium (S. Typhimurium) SA186 survive to the intestinal challenge and, compared to control mice, show a reduced number of virulent bacteria in the gut, with milder signs of inflammation. This study demonstrates that the oral administration a of S. Typhimurium strain lacking ZnuABC is able to elicit an effective immune response which protects mice against intestinal S. Typhimurium infection. These results, collectively, suggest that the streptomycin-pretreated mouse model of S. typhimurium infection can represent a valuable tool to screen S. typhimurium attenuated mutant strains and potentially help to assess their protective efficacy as potential live vaccines.

Protective properties of rifampin-resistant rough mutants of Brucella melitensis.

Vaccination against Brucella infections in animals is usually performed by administration of live attenuated smooth B. abortus strain S19 and B. melitensis strain Rev1. They are proven effective vaccines against B. abortus in cattle and against B. melitensis and B. ovis in sheep and goats, respectively. However, both vaccines have the main drawback of inducing O-polysaccharide-specific antibodies that interfere with serologic diagnosis of disease. In addition, they retain residual virulence, being a cause of abortion in pregnant animals and infection in humans. To overcome these problems, one approach is to develop defined rough mutant Brucella strains lacking O antigen of lipopolysaccharide. B. abortus rough strain RB51, a rifampin-resistant mutant of virulent strain B. abortus 2308, is used as a vaccine against B. abortus infection in cattle in some countries. However, RB51 is not effective in sheep, and there is only preliminary evidence that it is effective in goats. In this study, we tested the efficacies of six rifampin-resistant rough strains of B. melitensis in protecting BALB/c mice exposed to B. melitensis infection. The protective properties, as well as both humoral and cellular immune responses, were assessed in comparison with those provided by B. melitensis Rev1 and B. abortus RB51 vaccines. The results indicated that these rough mutants were able to induce a very good level of protection against B. melitensis infection, similar to that provided by Rev1 and superior to that of RB51, without inducing antibodies to O antigen. In addition, all B. melitensis mutants were able to stimulate good production of gamma interferon. The characteristics of these strains encourage further evaluation of them as alternative vaccines to Rev1 in primary host species.

Liver cirrhosis: epidemiological aspects in Italy.

In order to improve our knowledge of the incidence of liver cirrhosis in Italy, we conducted two epidemiological studies. The first study showed that about 15% of asymptomatic subjects with persistent increase in alanine aminotransferase had histological evidence of cirrhosis. In this setting, cirrhosis was associated with viral aetiology in 91.4% of cases. In the second study, which enrolled cirrhosis patients from 13 centres from all regions of the country, viral infections were detected in 82.6% of patients, the large majority of whom, 71.2%, were positive for hepatitis C virus (HCV). Alcohol abuse was present in 8.7% of cases as exclusive aetiological factor. All the patients were classified according to Child-Pugh and were scored as class A in 62.4%, as class B in 23.8% and as class C in 13.8% of cases. The age distribution showed that about 55% of cirrhosis patients were under 60 years of age; 34.3% of them had a Child-Pugh score of class B or C. These data show that HCV infection represents the predominant aetiological factor of cirrhosis in Italy and that cirrhosis can be found frequently in asymptomatic subjects.

Laparoscopic tension-free repair of large paraesophageal hernias.

The paraesophageal hernia is an unusual disorder of the esophageal hiatus that may be associated with life-threatening mechanical problems. Elective repair is recommended at the time the condition is diagnosed, and open surgery can be accomplished with a low incidence of complications. The option of performing these repairs through a laparoscopic approach may further reduce morbidity and recovery time associated with surgical intervention. The purpose of this report was to review available options for laparoscopic repair and to present our experience with a tension-free technique for large paraesophageal hernias. Three patients with large diaphragmatic defects had laparoscopic repairs using an expanded polytetrafluorethylene (PTFE) patch secured with intracorporeal suturing techniques. One of these patients also underwent laparoscopic Toupet fundoplication in conjunction with repair of the hernia. In the other two patients, the fundus was secured to the right diaphragmatic crus to reduce the potential for recurrence and minimize postoperative reflux symptoms. All patients underwent successful repair without perioperative complications and had excellent long-term results. Laparoscopic repair of paraesophageal hernias can be accomplished by a number of different reported techniques. The use of a tension-free repair with PTFE may be particularly suitable for large diaphragmatic defects. An antireflux operation may be added selectively depending on clinical circumstances.

Intraoperative high-dose rate interstitial irradiation of hepatic metastases from colorectal carcinoma. Results of a phase I-II trial.

BACKGROUND: Resection of liver metastases from colorectal carcinoma can be curative. Unresectable but liver-confined metastases might be ablated by high-dose radiation with a similar curative result. METHODS: At Georgetown University Hospital, 22 patients with unresectable hepatic metastases from colorectal carcinoma underwent 24 interstitial irradiation procedures at laparotomy in a Phase I-II study. A single dose was administered with a high-dose rate iridium-192 afterloader. Dose to the tumor periphery was 20 Gy, 25 Gy, and 30 Gy in 13, 9, and 2 procedures, respectively. RESULTS: No acute or chronic radiation toxicity has occurred at a median follow-up of 11 months. Median actuarial local control at irradiated sites was 8 months, with 26% actuarial local control at 26 months by computed tomography (CT) or magnetic resonance imaging (MRI) scanning. In the two patients undergoing two procedures each, a second biopsy of previously irradiated areas demonstrated tumor eradication. CONCLUSIONS: This innovative, radical approach to unresectable colorectal hepatic metastases proved safe. Additional study is needed to determine whether interstitial irradiation is as effective as surgical resection, or whether it alters the natural history of the disease or longevity.

Evaluating the appropriateness of a nurse expert system's patient assessment.

The Urological Nursing Information System (UNIS) is an expert-system prototype designed to help nurses perform patient assessments on elderly nursing home residents known to be incontinent of urine. A study was conducted to evaluate the appropriateness of the patient-assessment parameters stored in the knowledge base of UNIS. These parameters were stored as objects--a kind of template for holding related clusters of data, facts, rules, hypotheses, or any knowledge in a single conceptual unit. Each object was rated for its appropriateness by 14 nurse experts. Resulting scores ranged from +14 to -14. The effect of the nurse experts' educational backgrounds and work settings on their ratings were also analyzed. The results indicated that 95.6% of the objects received favorable ratings from the nurse experts. Educational background was not a significant factor chi 2 = 5.2, but work settings did have a significant affect chi 2 = 21.07, p = 0.01.

Evaluation of UNIS: Urological Nursing Information Systems.

Unis is a nurse expert system prototype specifically designed to assist nurses caring for elderly, incontinent patients residing in nursing homes. Two studies measuring the performance level of UNIS were implemented. In the first study, results of sessions with UNIS on case studies of elderly, incontinent patients were compared to sessions with nurse experts. The relevance of questions, value of recommendations and overall performance were rated by an evaluation panel. In the second study, UNIS was implemented on two nursing units in a nursing home. The number of wet occurrences of patients residing on units where UNIS was consulted by nurses was compared to the number of wet occurrences of patients residing on units where UNIS was not consulted by nurses. The knowledge of urinary incontinence of nurses who consulted UNIS and those who did not consult UNIS were also compared. The results indicate that when judged by an evaluation panel, the relevance of the questions and value of the recommendations generated by UNIS were not rated significantly different than ratings assigned to nurse experts consulting on the same case studies. There was a significant difference between assigned ratings for overall performance; F.01 (4,16) = 10.4. UNIS scored the highest on four out of five case studies. In the second study, the number of wet occurrences of patients residing on units where nurses consulted UNIS decreased significantly; F.01 (2,9) = 34.67. The knowledge of urinary incontinence also improved significantly when nurses' consulted UNIS; F.001 (2,157) = 19.46. The methods and results of these two studies are presented.

Hepatic estrogen and progesterone receptors in an estrogen-associated hepatic neoplasm.

A patient with a benign hepatic neoplasm developing after treatment with estrogenic hormones is described. After excision, the neoplastic tissue was analyzed for the presence of cytosol estrogen and progesterone binding proteins. The neoplasm was classified as focal nodular hyperplasia of the liver and was demonstrated to contain high-affinity cytosol estrogen and progesterone hormone receptors. The estrogen-binding affinity of the neoplasm was three times greater than that of normal liver. Further investigation of cytosol hormone receptors in estrogen associated hepatic neoplasms will be required to define the role of these binding proteins in the possible etiology of certain liver tumors.

PIP: The case report for a patient with a benign hepatic neoplasm which developed following estrogenic hormone treatment is described. After excision, the neoplastic tissue was biopsied and found to contain high-affinity cytosol estrogen and progesterone hormone receptors. It is hypothesized that a small proportion of normal hepatic cells have relatively high concentrations of cytosol estrogen receptors, rendering them susceptible to stimulation to a neoplastic state by estrogen. In order to clarify the role of these binding proteins in the possible etiology of certain liver tumors, further investigation of cytosol hormone receptors in estrogen-associated hepatic neoplasms will be necessary.