Properties of mouse embryo fibroblasts transformed in vitro by infectious bovine rhinotracheitis virus.

Infection of CD-1 mouse embryo fibroblast(s) (MEF) with infectious bovine rhinotracheitis virus (IBRV) strain HMC resulted in persistent infection and subsequent transformation of these cells. IBRV-transformed MEF cultures consisted of short fibroblastoid cells, and IBRV-specific membrane and intracellular antigens were detectable in early in vitro passages by indirect imunofluorescence (IF) techniques. The presence of IBRV genetic information was confirmed in IF-positive and IF-negative cells by in situ hybridization. IBRV-transformed MEF induced fibrosarcomas in athymic nude mice given sc transplants. Infectious virus could not be rescued from the transformed cells or from tumor cells by cocultivation with rabbit kidney cells, by treatment with 5-iodo-2'-deoxyuridine, or by UV irradiation. Nontransformed control cells did not survive more than 10 in vitro passages and did not induce tumors when transplanted to athymic nude mice. These observations represent new data concerning the mouse cell-transforming potential of IBRV and confirm the presence of at least part of the virus genome in the transformants.

Noninvasive characterization of stunned, hibernating, remodeled and nonviable myocardium in ischemic cardiomyopathy.

OBJECTIVES: We evaluated a novel protocol of dual-isotope, gated single-photon emission computed tomographic (SPECT) imaging combined with low and high dose dobutamine as a single test for the characterization of various types of altered myocardial dysfunction. BACKGROUND: Myocardial perfusion tomography and echocardiography have been used separately for the assessment of myocardial viability. However, it is possible to assess perfusion, function and contractile reserve using gated SPECT imaging. METHODS: We studied 54 patients with ischemic cardiomyopathy using rest and 4 h redistribution thallium-201 imaging and dobutamine technetium-99m sestamibi SPECT imaging. The sestamibi images were acquired 1 h after infusion of the maximal tolerated dose of dobutamine and again during infusion of dobutamine at a low dose to estimate contractile reserve. Myocardial segments were defined as hibernating, stunned, remodeled or scarred. RESULTS: Severe regional dysfunction was present in 584 (54%) of 1,080 segments. Based on the combination of function and perfusion characteristics in these 584 segments, 24% (n = 140) were labeled as hibernating; 23% (n = 136) as stunned; 30% (n = 177) as remodeled; and 22% (n = 131) as scarred. Contractile reserve, represented by improvement in wall motion/thickening by low dose dobutamine, was observed in 83% of stunned, 59% of hibernating, 35% of remodeled and 13% of scarred myocardial segments (p<0.05). CONCLUSIONS: It is possible with this new imaging technique to characterize dysfunctional myocardium as stunned, hibernating, remodeled and nonviable. These subtypes often coexist in the same patient.

Acquired immunodeficiency syndrome-like illness associated with systemic Mycoplasma fermentans infection in a human immunodeficiency virus-negative homosexual man.

A 35-year-old homosexual man developed a composite nodal Kaposi's sarcoma and peripheral T-cell lymphoma that were associated with a peripheral blood CD4-positive lymphocyte count of only 43/mm3. The patient subsequently developed Pneumocystis carinii pneumonitis and eventually died due to disseminated Cryptococcus neoformans. Numerous premortem tests for the presence of human immunodeficiency virus (HIV) types 1 and 2 were negative by the enzyme-linked immunosorbent assay, Western blot, viral isolation, and polymerase chain reaction techniques. Postmortem evaluations for HIV-1, HIV-2, human T-cell lymphotropic virus (HTLV)-I, and HTLV-II also were negative by polymerase chain reaction, immunofluorescence assays, and viral isolation. A systemic infection by Mycoplasma fermentans, however, was documented by immunohistochemistry and polymerase chain reaction in premortem and postmortem tissues. This recently recognized human pathogen has produced systemic infections in patients with the acquired immunodeficiency syndrome (AIDS) and in previously healthy non-AIDS patients who characteristically have a fulminant flu-like illness. Additionally, M fermentans has enhanced the cytopathic effect of HIV in in vitro studies and has produced fatal wasting illnesses with terminal lymphopenia in inoculated adult silvered leaf monkeys. This report is the first description of an association between M fermentans infection and an AIDS-like illness in an HIV-negative individual. The etiology of the severe immunosuppression in this patient and the associated role of M fermentans remain to be determined by further investigations.

Evaluation of the variety of plasmid profiles in S epidermidis isolates from hospital patients and staff.

Plasmid profiling was used to determine the variability of normal flora isolates of Staphylococcus epidermidis in order to evaluate the usefulness of plasmid profiling for identifying pathogens. Fifteen hospital staff members and patients repeatedly had cultures taken from the hands and nares, and multiple isolates were examined for plasmid profiles. S epidermidis isolated from the nares of 15 neonates were also examined. The total number of isolates examined for plasmid profiles was 726. Repetition of profiles was common among the different isolates from a single sampling (one swab). The frequency of re-isolating similar profiles on different days varied from 7% to 13%. Simultaneous isolation of similar profiles from nares and hands on the same individual varied from 0% to 11%, the percentage being lower for personnel. Isolation of the same plasmid profile from different individuals occurred only twice and resulted in an assignment probability of Pa = 0.002 for isolates obtained from different individuals. Significantly more isolates from nares contained plasmids (97%) compared with isolates from hands (89%). Patients who had two or more isolates of coagulase-negative staphylococci with similar profiles were judged, clinically, to have infections in 12 of 13 cases. However, the likelihood of re-isolating an S epidermidis strain with a similar plasmid profile twice from the same person at different times was sufficiently high to prevent plasmid profiling from being used as an absolute criterion for infection.

Detection of Chlamydia trachomatis in genital specimens by the Microtrak direct specimen test.

The conventional cell culture method for detection of Chlamydia trachomatis requires two to six days and is technically difficult to perform. The authors evaluated a new, relatively simple, non-culture method (MicroTrak, Syva Co., Palo Alto, CA) that requires less than one hour to complete. Two hundred fifty-one cervical and 209 male urethral specimens from three Richmond health clinics were read by direct immunofluorescence staining and compared with cell culture technics using iodine staining. Patient specimens were applied directly onto microscope slides (8 mm well) and stained with a fluorescein-labeled monoclonal antibody. Slides were examined for 10-15 minutes at X1,000 using an AO epifluorescent microscope and were considered positive if five or more typical elementary bodies were seen. The sensitivity, specificity, positive and negative predictive values for the direct smear were 89%, 97%, 85%, and 98% for males, and 93%, 96%, 85%, and 98% for females, respectively. The rapid direct specimen test appears to be a satisfactory method for detecting chlamydia in male and female genital specimens.

Association of the virus-like infectious agent originally reported in patients with AIDS with acute fatal disease in previously healthy non-AIDS patients.

We studied 6 patients from 6 different geographic areas who presented with acute flu-like illnesses. The patients developed persistent fevers, lymphadenopathy or diarrhea, pneumonia, and/or heart, liver, or adrenal failure. They died in 1-7 weeks. These patients had no serological evidence of HIV infection and could not be classified as AIDS patients according to CDC criteria. The clinical signs as well as laboratory and pathological studies of these patients suggested an active infectious process, although no etiological agent was found despite extensive infectious disease work-ups during their hospitalization. Post-mortem examinations showed histopathological lesions of fulminant necrosis involving the lymph nodes, spleen, lungs, liver, adrenal glands, heart, and/or brain. No viral inclusion cells, bacteria, fungi, or parasites could be identified in these tissues using special tissue stains. We report that immunohistochemistry using rabbit antiserum raised against VLIA, the virus-like infectious agent previously identified in patients with AIDS and shown to cause fatal systemic infection in primates, revealed VLIA antigens in these necrotizing lesions. In situ hybridization using an 35S labeled VLIA-specific DNA probe also detected VLIA genetic material in the areas of necrosis. Furthermore, virus-like particles closely resembling VLIA were identified ultrastructurally in these histopathological lesions. VLIA was associated with the systemic necrotizing lesions in these previously healthy non-AIDS patients with an acute fatal disease.

Identification of Mycoplasma incognitus infection in patients with AIDS: an immunohistochemical, in situ hybridization and ultrastructural study.

Monoclonal antibodies (Mabs) were developed against antigens from a pure culture of Mycoplasma incognitus grown in modified SP-4 medium. All the Mabs obtained were shown to react only with M. incognitus, and not with other species of human mycoplasma. The Mabs identified M. incognitus immunohistologically in thymus, liver, spleen, lymph node, or brain from 22 patients with AIDS, as well as in 2 placentas delivered by patients with AIDS. Using an 35S-labeled DNA probe specific for M. incognitus and in situ hybridization technique, we also identified M. incognitus-specific genetic material in these tissues. Furthermore, ultrastructural studies of the specific areas of tissues which were highly positive for M. incognitus antigens revealed characteristic structures of mycoplasma organisms. These mycoplasma-like particles could be identified intracellularly and extracellularly. Histopathology of the tissues infected by M. incognitus varied from no pathological changes to fulminant necrosis with or without an associated inflammatory reaction. M. incognitus, a novel pathogenic mycoplasma, was cytopathic and cytocidal.

Detection and isolation of Mycoplasma fermentans from urine of human immunodeficiency virus type 1-infected patients.

Mycoplasma fermentans (incognitus strain) has been linked with acquired immunodeficiency syndrome-associated nephropathy. Ten (23%) of 43 urine sediment specimens from 40 human immunodeficiency virus (HIV)-positive patients at different stages of acquired immunodeficiency syndrome disease tested positive in the polymerase chain reaction using a primer pair found in the insertion sequences specific to M fermentans. Mycoplasma fermentans was isolated from two HIV-positive patients' urine sediment specimens and on a repeated basis from one. All three culture-positive urine sediment specimens tested positive in the polymerase chain reaction. Fifty urine sediment specimens from age-matched HIV-negative healthy controls tested negative for M fermentans by polymerase chain reaction. Mycoplasma fermentans was not isolated from any of the control urine sediment specimens. Our results show a high prevalence of M fermentans in urine sediment specimens from HIV-positive patients but not from urine sediment specimens of HIV-negative healthy controls.

Induction of persistent infection in mice and oncogenic transformation of mouse macrophages with infectious bovine rhinotracheitis virus.

Infectious bovine rhinotracheitis virus (IBRV) established long-term persistent infection in intracerebrally inoculated athymic nude mice. After intraperitoneal injection into outbred mice, virus was isolated for only 3 days from spleens and livers. In vitro inoculation of outbred mouse spleen fragments with IBRV resulted in persistent infection and subsequent transformation of spleen macrophages. The IBRV-specific membrane and intracellular antigens were detected by indirect immunofluorescence techniques in transformed cells in early in vitro passages. The presence of IBRV genetic formation was confirmed by in situ hybridization. The IBRV-transformed mouse macrophages induced fibrosarcomas and cystic tumors in athymic nude mice. Infective virus could not be rescued from transformed cells by cocultivation with rabbit kidney cells, treatment with iododeoxyuridine, or ultraviolet irradiation.

Using locus of control to empower student nurses to be professional.

The author examines locus of control as a factor in some educational problems. Characteristics and implications of internal and external locus of control are identified; and strategies are presented to promote assertiveness, accountability, and independence in students who previously avoided risking-taking behaviors.

Dissemination of behavioural activation for depression to mental health nurses: training evaluation and benchmarked clinical outcomes.

Depression causes significant distress, disability and cost within the UK. Behavioural activation (BA) is an effective single-strand psychological approach which may lend itself to brief training programmes for a wide range of clinical staff. No previous research has directly examined outcomes of such dissemination. A 5-day training course for 10 primary care mental health workers aiming to increase knowledge and clinical skills in BA was evaluated using the Training Acceptability Rating Scale. Depression symptom level data collected in a randomized controlled trial using trainees were then compared to results from meta-analysis of studies using experienced therapists. BA training was highly acceptable to trainees (94.4%, SD 6%). The combined effect size of BA was unchanged by the addition of the results of this evaluation to those of studies using specialist therapists. BA offers a promising psychological intervention for depression that appears suitable for delivery by mental health nurses following brief training.

Sex and other predictors of intra-aortic balloon counterpulsation-related complications: prospective study of 1119 consecutive patients.

BACKGROUND AND OBJECTIVE: Intra-aortic balloon counterpulsation (IABC) complication rates remain significant despite technical advances that have simplified and expanded its use. Previous reports implicated patient height, diabetes, or peripheral vascular disease as risk factors. However, these studies were small and not prospective. Therefore a prospective study at one high-volume center was conducted examining the complications associated with IABC and the role of sex and other risk factors in the current era. METHODS: The study prospectively evaluated 1174 consecutive percutaneous IAB insertions in 1119 patients between 1993 and 1997. Major complications were defined as embolism or limb ischemia requiring surgery; bleeding requiring transfusion or surgery; systemic infection; balloon rupture; or death from one of these causes. Minor complications were defined as limb ischemia or pulse loss resolving without surgery or after IAB removal or bleeding not requiring transfusion or surgical intervention. All variables were analyzed with univariate and stepwise multivariate analysis. RESULTS: Data were collected on 1119 patients (727 men and 392 women) with a mean age of 65 +/- 11 years. The prevalence of diabetes, hypertension, and peripheral vascular disease was 27%, 52%, and 8%, respectively. Complications occurred in 166 patients (15%) and a major complication occurred in 126 (11%) of the 1119 patients. Multivariate logistic regression analysis was done with demographic, clinical, and procedural variables in a cohort of 1106 patients. The analysis identified peripheral vascular disease (relative risk [RR] 4.1), female sex (RR 2.3), and body surface area (RR 0.26 per m(2)) as independent predictors of a major complication. In addition, cardiac index (RR 0.7) was also identified as an independent predictor of any or major complications in a subset of 915 patients. In 754 high-risk patients (women or patients with peripheral vascular disease, diabetes, cardiac index <2.2 L/min/m(2), or body surface area <1.8 m(2)), 114 major complications occurred (15%) compared with 8 (3%) among 278 non-high-risk patients (P <.0001). CONCLUSIONS: The current complication rate associated with IABC remains significant. Advances in IAB technology need to focus on the high-risk subset of patients that includes women, smaller patients, and those with peripheral vascular disease.

Selective detection of Mycoplasma fermentans by polymerase chain reaction and by using a nucleotide sequence within the insertion sequence-like element.

A new assay using the polymerase chain reaction to amplify a 206-nucleotide specific gene sequence within the insertion sequence-like element of Mycoplasma fermentans has been developed. The unique insertion sequence-like element exists in multiple copies in the M. fermentans genome. The assay selectively amplifies DNA from all strains of M. fermentans tested. In contrast, DNA from other species of human and nonhuman mycoplasmas, common tissue culture-contaminating mycoplasmas, and bacteria, as well as human, monkey, and mouse tissues do not produce the amplified DNA products specific for M. fermentans.

Identification of a herpesvirus isolated from cytomegalovirus-transformed human cells.

Human cells transformed by cytomegalovirus and transplanted to athymic nude mice yielded a cytopathic virus, Hershey Medical Center virus, following prolonged in vitro passage of the tumor cells. The virus is a double-enveloped herpesvirus, is sensitive to ether, and is inhibited by iododeoxyuridine. No significant antigenic relationship to herpes simplex virus was detected using herpes simplex virus-immune sera in neutralization and immunofluorescence tests, but indirect immunofluorescence tests revealed cytomegalovirus-related antigenicity. Further immunological tests revealed that Hershey Medical Center virus is antigenically indistinguishable from infectious bovine rhinotracheitis virus. Thus, it appears that Hershey Medical Center virus is infectious bovine rhinotracheitis virus, which presumably appeared in the cell culture as a contaminant from fetal calf serum.

Total volume culture technique for the isolation of microorganisms from continuous ambulatory peritoneal dialysis patients with peritonitis.

A total volume method of culturing dialysis fluid from continuous ambulatory peritoneal dialysis patients during episodes of peritonitis was developed. Concentrated culture media stored in small blood transfer bags were added directly to the drained dialysate exchange bags by the same technique used to carry out the dialysate exchange. The exchange bag with the added culture medium was incubated at 35 degrees C and observed for turbidity. Seventy-eight dialysis exchange bags from patients without clinical peritonitis (negative controls) and forty-eight dialysis exchange bags from patients with clinical peritonitis were cultured. Bacteria were recovered from all cultures of patients with clinical peritonitis (100% sensitivity) and from five cultures of negative control fluids (94% specificity). Of these isolates, 86% were gram positive, and 14% were gram negative. This technique represents an advance over previously described culture techniques in its ability to isolate the causative organism(s) in cases of peritonitis in continuous ambulatory peritoneal dialysis patients.