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The article considers factors that influence pathogenesis, initiation of infection, dissemination of virus within a host, lytic viral infections, viral immunosuppression, viral immunopathology, and viral oncogenesis.

Background The nanocrystalline silver (NCS) dressing Acticoat is commonly used in clinical practice for the treatment of burns and other open wounds as a topical antimicrobial. The dressing may dry resulting in traumatic dressing changes; hence the variety of contact layer dressings used in conjunction with it. Dressing combinations that do not permit NCS penetration are not cost effective and deprives the wound of the needed anti-microbial. Methods Common wound pathogens were subjected to a variety of contact layer dressings underlying the NCS dressings. The zone of inhibition (ZOI) obtained was measured and compared to a control. Results Intrasite gel demonstrated a synergistic effect with Acticoat. Iruxol exhibits antagonism by preventing penetration and is known to be partially deactivated by NCS. Intrasite conformable and Adaptic allowed partial penetration while the discs of Biobrane, unstretched/non-fenestrated Pelnac and Telfa transparent film did not allow for sufficient penetration to inhibit the underlying bacteria in this study. The cadaver skin from the South African skin bank (Tshwane university of Technology) displayed a greater antimicrobial effect than even the Acticoat control. Conclusion Our results illustrate that we should perhaps reconsider dressing combination choices with Acticoat in view of their redundancy or synergistic effect.

Background Tranexamic acid reduces blood loss and transfusion requirements in cardiac surgery but may increase the risk of coronary graft thrombosis. We previously reported the 30-day results of a trial evaluating tranexamic acid for coronary artery surgery. Here we report the 1-year clinical outcomes. Methods Using a factorial design, we randomly assigned patients undergoing coronary artery surgery to receive aspirin or placebo and tranexamic acid or placebo. The results of the tranexamic acid comparison are reported here. The primary 1-year outcome was death or severe disability, the latter defined as living with a modified Katz activities of daily living score of less than 8. Secondary outcomes included a composite of myocardial infarction, stroke, and death from any cause through to 1 year after surgery. Results The rate of death or disability at 1 year was 3.8% in the tranexamic acid group and 4.4% in the placebo group (relative risk, 0.85; 95% confidence interval, 0.64-1.13; P = .27), and this did not significantly differ according to aspirin exposure at the time of surgery (interaction P = .073). The composite rate of myocardial infarction, stroke, and death up to 1 year after surgery was 14.3% in the tranexamic acid group and 16.4% in the placebo group (relative risk, 0.87; 95% CI, 0.76-1.00; P = .053). Conclusions In this trial of patients having coronary artery surgery, tranexamic acid did not affect death or severe disability through to 1 year after surgery. Further work should be done to explore possible beneficial effects on late cardiovascular events.

Background The deficit of donor sites in major burns over 50% of the total body surface area has necessitated the application of methods besides traditional meshed autografting to achieve definitive skin cover. The Meek micrografting technique was introduced at this hospital in 2011, especially in the absence of a reliable source of deceased donor allograft skin. The purpose of this study was to evaluate this strategy with reference to its technical execution, efficacy and indications in the context of major paediatric burn surgery. Methods A cohort study was performed of all paediatric patients with major burn who underwent Meek micrografting at a dedicated paediatric burn centre in a developing country over a five year period. Demographics, details of their burns, operative management and clinical course and outcomes were collected from patient records and operative notes and analysed. Results Thirty-five patients were managed using the micrografting technique during the study period. The mean patient age was 4.1 years (range 3 months–11 years) and their mean total body surface area (TBSA) burn was 49.7% (range 15–86%). Eleven patients sustained inhalation injuries and five developed a re-feeding syndrome on account of delayed referral. The mean abbreviated burn severity index (ABSI) was 8.5 (range 2–13). The hospital length of stay in the 27 survivors was a mean of 75.5 days, equating to 1.4 days per percentage burn. Eight patients died during the course of treatment, with a mean TBSA burn of 67.75% (range 38–86%). Graft take one month after surgery was documented to be more than 90% in 24 patients, of whom 3 subsequently died. Eleven patients had less than 90% graft take at this time, of whom 5 died. Conclusion There is a considerable ‘learning curve’ associated with this technique. In order to achieve success one must ensure a completely viable, non-infected bed, obtained by tangential or fascial excision, followed by allografting as temporary coverage and to ‘test the wound bed’ for definitive coverage. Infection resulted in the majority of autograft loss in this series, and in addition to risk factors like burn size and inhalation injury, accounted for many of the deaths in this series. Meek micrografting offers high expansion ratios, thereby facilitating durable wound cover in the presence of limited donor sites. It is unlikely that a lethal dose, 50% (LD50) of almost 70% TBSA would have been possible in this context without the regular application of this technique. This study advocates for the widespread availability of Meek micrografting and deceased donor allograft skin in developing countries.

TD-1792 is a first-in-class glycopeptide-cephalosporin heterodimer that exhibits bactericidal activity against Gram-positive pathogens. We conducted a randomized, double-blind, active-control, phase II trial in patients with complicated skin and skin structure infections caused by suspected or confirmed Gram-positive organisms. Patients 18 to 65 years old were randomized to receive 7 to 14 days of either TD-1792 (2 mg/kg of body weight intravenously [i.v.] every 24 h [q24h]) or vancomycin (1 g i.v. q12h, with dosage regimens adjusted per site-specific procedures). A total of 197 patients were randomized and received at least one dose of study medication. Rates of clinical success at the test-of-cure evaluation were similar in all analysis populations. Among 170 clinically evaluable patients, cure rates were 91.7% and 90.7% in the TD-1792 and vancomycin groups, respectively (95% confidence interval [CI] of −7.9 to 9.7 for the difference). In microbiologically evaluable patients with methicillin-resistant Staphylococcus aureus at baseline ( n = 75), cure rates were 94.7% in the TD-1792 group and 91.9% in the vancomycin group. Microbiological eradication of Gram-positive pathogens ( n = 126) was achieved in 93.7% and 92.1% of patients in the TD-1792 and vancomycin groups, respectively. Seven patients were discontinued from study medication due to an adverse event (AE): 2 and 5 in the TD-1792 and vancomycin groups, respectively. AEs were of similar types and severities between the two groups, other than pruritus, which was more common in patients who received vancomycin. No patients in the TD-1792 group experienced a serious AE. This study supports further clinical development of TD-1792 in patients with Gram-positive infection.

Introduction Developing countries often have limited funds and thus diagnostic and treatment modalities should be operated in a cost effective manner while maintaining proper patient care. Gamma camera collimators are acquired at additional cost and the pinhole collimator is often more expensive than the more commonly used Low-energy-high-resolution (LEHR) collimator. The aim of this study was to compare the image quality of a pinhole and parallel-hole collimator using a thyroid phantom. Materials and Methods The thyroid phantom is a perspex block of 10 × 10 cm with thickness of 3 cm. It contained a cavity of an average human thyroid with one hot spot and three cold spots of different sizes and locations. A defect was placed on the phantom at different locations and 53 MBq Tc-99m was injected into the phantom and imaged using the following imaging protocols; (i) clinical protocol as specified by the manufacturer, (ii) equivalent count densities for the pinhole and parallel hole, (iii) equivalent zoom factor for both collimators, (iv) variable detector to phantom distance for the parallel hole collimator. The images were assessed for defect detectability, contrast and sensitivity using human observers. Results All the observers could find the defect for all imaging protocols when the pinhole collimator was used, while in the case of the parallel hole collimator this was only possible when the detector to phantom distance was decreased. The pinhole collimator had superior contrast to that of the parallel hole collimator. As expected the sensitivity of the pinhole collimator was less than that of the parallel hole collimator. Conclusion From this study it is evident that the image quality of the pinhole collimator is superior to the parallel-hole collimator and therefore acquiring a pinhole collimator for thyroid imaging on the gamma camera is justified.

A polymerase chain reaction (PCR) technique, targeting a chromo-helicase DNA-binding protein (CHD) gene, was used to determine gender in birds. DNA from 87 birds, representing 31 species from 9 of the 20 orders of birds, was evaluated. The DNA was extracted from as little as 5 μ l of whole blood, and CHD-specific primers (P2 and P8) were used to amplify the CHD gene. Polymerase chain reaction products were then subjected to restriction fragment length polymorphism analysis. Gender was determined by distinguishing between the female CHD-W gene and the male CHD-Z gene by agarose gel electrophoresis of the digested PCR products. The PCR assay using the HaeIII restriction enzyme helped identify gender in all species evaluated except those from the Order Anseriformes. Isolation of the CHD-Z and CHD-W fragments was performed, and the genes were cloned and sequenced in a number of waterfowl species. On the basis of sequence results for the CHD-Z and CHD-W genes for both the mallard duck (Anas platyrhync...

Chronic renal failure has on occasion been referred to as a state of calcium toxicity. The aim of this study was to investigate the status of intracellular free Ca 2+ in the neutrophils of chronic renal failure patients on maintenance haemodialysis treatment. Factors previously suggested to influence intracellular free Ca 2+ were investigated including PTH levels, oxidative stress and recombinant human erythropoietin administration. The study involved 14 chronic renal failure patients on the haemodialysis programme of the Pretoria Academic hospital. Intracellular free Ca 2+ and transmembrane Ca 2+ fluxes were investigated by fluorescence spectrophotometry. Increases above control values were found in intracellular free Ca 2+ (P-value 0.0242) and in the transmembrane Ca 2+ flux upon fMLP stimulation (P-value 0.0002). The results showed significant differences in intracellular free Ca 2+ between patients on rHuEPO and patients not on rHuEPO. The apparently rHuEPO-induced increase in intracellular free Ca 2+ persisted in the presence of calcium channel blockers. No overt indications of oxidative stress could be detected by the antioxidant vitamin levels. It is concluded that factors other than those associated with uraemia, such as rHuEPO administration, might contribute to the often reported increase in intracellular free Ca 2+ in these patients. Further studies to investigate the relationship between intracellular free Ca 2+ , rHuEPO and calcium channel blockers are suggested.

This study describes a congenital deformity of the shoulder joint in a 5-year-old female, associated with an undescended scapula and the presence of an omovertebral bone. Dissections on 16 cadavers were done to identify structures in danger of injure before operating on the patient. Surgeons need to take specific note of the dorsal scapular nerve. Clin. Anat. 15:139–142, 2002. © 2002 Wiley-Liss, Inc.

Ruminant respiratory syncytial viruses (RSVs) are classified into 2 subgroups, ovine RSV and bovine RSV. Although ovine RSV infects cattle, its contribution to bovine respiratory tract disease has not been established, which is an important issue for vaccine development in cattle. Diagnosis by virus isolation or serology has low or variable sensitivity and/or specificity and polymerase chain reaction (PCR) has been recommended as a rapid and sensitive technique for RSV detection. A simple procedure has been developed to detect and identify bovine and ovine RSVs. First, the nucleotide sequence of the ovine RSV fusion (F) gene was determined and compared with representative strains of bovine RSV and human RSV subgroups A and B. The ovine RSV F gene has 85 and 72–73% nucleotide identity with those of bovine RSV and human RSV, respectively. The predicted amino acid sequence of the ovine RSV F gene has 94 and 83–84% amino acid identity with those of bovine RSV and human RSV, respectively. Then PCR primers targeting a specific F gene fragment of bovine and ovine RSV were designed. The primers represented bases 85–103 and the complementary sequence to bases 510–493 of the ovine RSV F gene. A similar PCR product (426 bp) was obtained on agarose gel electrophoresis from bovine RSV and from ovine RSV. The products, however, were unique to the parent virus and could be distinguished by EcoRI or MspI restriction endonuclease cleavage. EcoRI cleaved the ovine product into 2 bands (285 and 141 bp) but failed to affect the bovine RSV PCR product. However, MspI cleaved the bovine product into 2 bands (229 and 197 bp) but had no effect on the ovine product. Also, this assay did not amplify any PCR product with human RSV. The reverse transcription-polymerase chain reaction (RT-PCR) followed by restriction enzyme digestion is a useful and practical approach for detection and differentiation of ruminant respiratory syncytial viruses.

To compare subcutaneous PCA tramadol with subcutaneous PCA morphine for postoperative pain relief after major orthopaedic surgery and for the incidence of side-effects.In a double-blind randomised controlled study 40 patients (20 in each group) self-administered either tramadol or morphine for 72 hr after surgery via s.c. PCA. The following variables were recorded at various time intervals: (i) pain score by means of a visual analogue scale, (ii) drug consumption and total PCA demands, (iii) vital signs (blood pressure and heart rate), (iv) oxygen saturation and respiratory rate, and (v) side-effects (sedation, nausea/vomiting, pruritus, urinary retention and constipation).Both drugs provided effective analgesia. The mean consumption in the first 24 hr was 792 +/- 90 mg tramadol and 42 +/- 4 mg morphine. Thereafter, consumption of both drugs declined markedly. Moderate haemodynamic changes were observed in both the tramadol and morphine groups (with a maximum 20% decrease in mean blood pressure and a maximum 17% increase in heart rate) during the 72 hr period. Both tramadol and morphine were associated with a clinically and statistically significant (P0.001) decrease in oxygen saturation, but without changes in respiratory rates. Desaturation was less marked with tramadol. Tramadol appeared to cause more nausea and vomiting than morphine. Sedation was mild and only seen during the first few hours after surgery in both groups.Tramadol is an effective analgesic agent for the relief of acute postoperative pain when administered by PCA via the subcutaneous route. Under these conditions tramadol behaves much like morphine with a similar side-effect profile.

The diagnosis of severe infection, selection of an appropriate antibiotic to which the most likely pathogens are sensitive, its prompt administration at a sufficient dosage and adequate supportive therapy are critical to ensuring a favourable patient outcome. However, the progressive emergence of strains of microorganisms multiresistant to routinely used antibiotics is causing growing concern and increasing the difficulty of reliably achieving these goals, particularly when these organisms cause serious infections. Resistance is particularly common among organisms such as Pseudomonas aeruginosa and the staphylococci, and is increasingly being encountered in streptococci, enterococci, and Gram-negative bacilli such as Acinetobacter spp., Citrobacter freundii and Serratia spp. Resistance is more likely to appear when such pathogens are exposed to antibiotic concentrations at, above, or slightly below the minimum inhibitory concentration, which may result from inadequate dosages, administration via an inappropriate route, or the presence of bacteria in sequestered sites. The new extended spectrum fluoroquinolones such as clinafloxacin have significantly more activity against fluoroquinolone-resistant strains than ciprofloxacin, ofloxacin or fleroxacin, while retaining the properties that have made the fluoroquinolones such an attractive class of antibacterials over the past decade. However, there has been a rapid emergence of resistance to newer agents such as ciprofloxacin, which may be partly attributable to their repetitive use and to precursors such as nalidixic acid. Most resistance has occurred among hospitalised patients and seems to be due to cross-infection by a single resistant clone; this raises the possibility that, if used appropriately, clinafloxacin may not lose its advantage in helping to treat serious, multiresistant pathogens as rapidly as other antibacterials.

Although several viruses and bacteria are capable of inducing bovine respiratory tract disease, a pivotal organism in the cause of this complex disease may be bovine viral diarrhea virus (BVDV). Circumstantial evidence has long supported this hypothesis. It is frequently present in diseased respiratory tract tissues often together with other viruses or bacteria. Field observations suggest marked synergism occurs. Researchers have confirmed that, in most instances, the virus itself elicits only a mild respiratory tract disease in susceptible calves, but some strains may be much more pneumo-pathogenic than others. Experimental evidence now supports the hypothesis, that BVDV markedly enhances respiratory tract disease caused by IBRV, BRSV, or Pasteurella haemolytica; that it impairs pulmonary immunity; and that it, by itself, may produce mild respiratory tract disease.

Aims: The aim of this study was to assess static and dynamic bone changes in patients suffering from rickets. Methods and results: Transcortical iliac crest biopsies of 15 hospitalized children with rickets were taken after labelling new bone formation with two cycles of tetracycline administration 10 days apart. Undecalcified sections were prepared, appropriately stained and histomorphometric analysis performed. Static and dynamic bone changes were measured including the volume of bone and osteoid, trabecular and cortical bone dimensions and resorptive and mineralization activities. The results were compared with normal values. The nature of the mineralization fronts was noted. Trabecular osteoid volumes of all but one patient was above the normal range of 1.9% (± 0.4%). This patient suffered rickets associated with the Kwashiorkor–Marasmus syndrome. Tetracycline labelling was found to be more sensitive than subjective evaluation of the nature of the mineralization fronts. Despite a balanced hospital diet, a bone formation rate of zero was found in three cases, indicating a need for vitamin D and mineral supplementation. Seven cases had decreased mineralization lag times, indicating response to the balanced diet. Conclusions: This study showed that histometric analysis of labelled bone biopsies is a helpful adjunct to the diagnosis but particularly assessment of response to management of deficiency states in children.

To determine mortality and factors that might predict outcome in severe community-acquired pneumococcal pneumonia treated by a standard protocol.Prospective, non-concurrent study.Respiratory intensive care unit (ICU) in a teaching hospital.63 patients who were diagnosed by positive blood culture or Gram stain and culture of sputum or tracheal aspirate were included.Clinical features, severity scores including Acute Physiology and Chronic Health Evaluation (APACHE) II, organ failure and lung injury scores, and the clinical course in the ICU were documented; 79% of patients required mechanical ventilation. Bacteraemia was present in 34 patients (54%); there were no distinguishing clinical features between bacteraemic and non-bacteraemic cases. The overall mortality was 21%, with only 5 deaths (15% mortality) in the bacteraemic group. Shock and a very low serum albumin (26 g/l) were the only clinical features that differentiated survivors from non-survivors; lung injury, APACHE II and multiple organ failure scores were all predictive of outcome. The positive predictive value and specificity in predicting death in individuals for the modified British Thoracic Society rule 1 were 26 and 64%; APACHE II2057 and 88%;2 organ failure 64 and 92%; and lung injury233 and 73%, respectively.These results suggest that even in bacteraemic cases mortality should be below 25% with intensive care management and that conventional scoring systems, while predictive of group mortality, are unreliable in individuals.

The cytokine cascade which is triggered by severe sepsis may contribute to progressive organ dysfunction and death from sepsis. This cascade may be accentuated by surgery for sepsis and pre-treatment with cytokine blockers could possibly ameliorate the response. This prospective controlled study determined the effect of surgery in 11 haemodynamically stable patients undergoing laparotomy for intra-abdominal sepsis. Serum levels of endotoxin, IL-1, IL-6, IL-8 and TNF-α were determined; blood cultures, features of systemic inflammatory response, and organ dysfunction were monitored over the perioperative period. There was considerable variation in the serum cytokine levels. The preoperative IL-6 levels were significantly elevated in the septic patients and a threefold increase in IL-6 levels occurred in both groups postoperatively. An increase in TNF-α did not achieve significance because of high levels in control patients with cancer. Cytokine release which occurs during abdominal surgery is increased in patients with intra-abdominal sepsis.

When the intestinal flora is susceptible, selective decontamination of the digestive tract (SDD) reduces colonization of the alimentary tract by aerobic Gram-negative bacilli, and ventilator-associated pneumonia is seen in units with a high rate of nosocomial infection. Although mortality is generally unaltered in studies of SDD, a number of deaths can be directly attributed to ventilator-associated pneumonia; no study has yet had sufficient power to demonstrate a reduction in mortality. Reasons for failure of SDD include infections by organisms that are acquired directly into the trachea thus bypassing the digestive tract, and failure to prevent colonization of the alimentary tract by resistant micro-organisms. As with any excessive antibiotic usage, prolonged use of SDD is likely to have an impact on the microbial ecology of an intensive care unit, thus making microbiological surveillance essential. The role of SDD at present remains controversial, but may be helpful in intensive care units where there is a high incidence of secondary infection.

The role of selective decontamination of the digestive tract (SDD) for the prevention of nosocomial infection in critically ill patients remains controversial, and the efficacy of this technique in patients who are already infected on presentation to the intensive care unit has not previously been assessed. We performed a double-blind randomized placebo controlled trial of SDD (parenteral cefotaxime, six-hourly oral and enteral polymyxin E, tobramycin, and amphotericin B vs placebo) for all infected patients presenting to the ICU requiring mechanical ventilation for more than 48 hours and ICU stay of more than 5 days. Daily clinical and microbiological monitoring for secondary infection was undertaken until hospital discharge. In all, 59 selective decontamination and 76 placebo fully comparable patients fulfilled criteria for enrolment and analysis (APACHE II 15.2 vs 15.1). The number of patients receiving SDD who developed nosocomial infections was significantly reduced (P = 0.048), and there were no infections caused by the enterobacteriaceae or Candida spp in this group. No difference in ICU (17.5 vs 18.8 days) or hospital stay (32.7 vs 34.2 days) or mortality (17% vs 22.3%) was shown. Critically ill, primarily infected patients are protected from nosocomial infection by the use of SDD.

Respiratory syncytial viruses (RSVs) cause serious respiratory tract disease in infants and children worldwide and similar disease in calves. Strains have been isolated from other ruminant animals such as sheep and goats, but these viruses have not been characterized at the molecular level. In this study, we report the cloning and sequencing of four structural genes coding for the phosphoprotein, nucleocapsid (N) protein, matrix (M) protein and 22K protein of an ovine RSV strain. Comparisons of these sequences with those of bovine and human RSV show that the M and N proteins are the most conserved between ruminant RSV strains and the N protein is the most conserved protein between human and ruminant RSV strains. The attachment G glycoprotein and the small hydrophobic protein are the most divergent proteins among human and ruminant RSV subgroups.

OBJECTIVE To determine the value and safety of fiberoptic bronchoscopy in an intensive care unit (ICU). DESIGN Prospective survey. SETTING ICUs at a tertiary care hospital (except for seven procedures that were performed at a peripheral hospital ICU). PATIENTS A total of 107 patients with a mean age of 43.9 yrs (range 15 to 84). INTERVENTIONS One hundred forty-seven fiberoptic bronchoscopy procedures (116 performed on patients who were undergoing mechanical ventilation) were performed on 107 patients. Ninety-four procedures were for diagnostic reasons (upper and lower airway inspection, focal and diffuse pulmonary infiltrates), 37 for therapeutic reasons (bronchial toilet, pulmonary hemorrhage, endotracheal intubation), and 16 for both reasons. Topical anaesthesia was used for fiberoptic bronchoscopy; sedation was rarely needed. Appropriate diagnostic and therapeutic procedures were performed. MEASUREMENTS AND MAIN RESULTS Oxygen saturation, electrocardiogram, and blood pressure were monitored. Transbronchial biopsies (all on mechanical ventilation) for diffuse pulmonary infiltrates were diagnostic in five of seven cases, and were suggestive of the diagnosis in a further case. Endobronchial biopsies were not diagnostic in any of three cases. Bronchial brushings for microbiology were positive in nine of 50 procedures and for cytology in one of nine procedures. Protected specimen brushes for pulmonary infiltrates gave positive microbiology findings in five of 23 procedures. In pulmonary hemorrhage, focal bleeding was found in five cases, diffuse bleeding in four, and no bleeding source in three. In lobar atelectasis, bronchial toilet led to full reexpansion (n = 20 procedures), partial reexpansion (n = 5), and no change (n = 3). Intubation with fiberoptic bronchoscopy was successful in four of five patients. Hypoxemia (oxygen saturation < 90%) occurred in 29 procedures; it caused no problems. Complications included hemorrhage (n = 2), supraventricular tachycardia (n = 1), pneumothorax (n = 1), pneumatocele (n = 1), and bronchospasm (n = 1). No deaths were attributable to fiberoptic bronchoscopy. CONCLUSIONS Fiberoptic bronchoscopy in the ICU is safe, contributes valuable diagnostic information, and is useful for therapeutic purposes.

The use of selective decontamination of the digestive tract (SDD) as prophylaxis against nosocomial respiratory tract infection remains controversial, largely because of concerns that, in the long term, it may promote the emergence of antibiotic-resistant strains. This report describes the results of surveillance cultures and susceptibility testing undertaken during the course of a 2-year, double-blind study of the efficacy of SDD which was conducted in a respiratory intensive care unit (ICU). Surveillance specimens from the alimentary tract and trachea were obtained from each patient on admission and then twice weekly until 48 h after discharge from the unit. Specimens were cultured semiquantitatively and organisms from morphologically distinct colonies were identified by standard methods; the susceptibilities of these isolates were determined by the disc diffusion method. Five thousand, nine hundred and sixty surveillance samples from 239 patients were processed in this way. Compared with the placebo group, SDD caused a significant reduction in the incidence of colonization of the alimentary tract with aerobic Gram-negative bacilli (AGNB), and Candida spp. were almost totally eliminated. The incidence of colonization with enterococci increased in both groups, while the incidence of both colonization of the alimentary tract with strains of coagulase-negative staphylococci and methicillin-resistant Staphylococcus aureus and infection caused by these organisms increased in the SDD group. Acinetobacter spp. were the most common bacteria associated with unit-acquired colonization and lower respiratory tract infection in both groups. The acquisition of strains of Pseudomonas aeruginosa and cefotaxime- and/or tobramycin-resistant Enterobacteriaceae was significantly greater in the placebo group than in the SDD group, although tobramycin-resistant strains of Proteus, Morganella and Providencia spp. were isolated from three of 114 patients receiving SDD. The use of SDD did not lead to an overall increase in antibiotic resistance amongst the AGNB usually associated with ICU-acquired infection. However, colonization with strains which were either resistant to one or more of the antibiotic components of the regimen or which were not inhibited by the regimen was observed and may subsequently lead to infection.

Blood samples were collected from 108 wild hogs (Sus scrofa) from the Great Smoky Mountains National Park (GSMNP), USA, February to July 1990. We found no antibodies for swine brucellosis, pseudorabies, bovine virus diarrhea virus or porcine rotavirus infection. Antibody titers to porcine parvovirus were found in 15 (14%) samples and antibody to one or more leptospiral serovars was found in 48 (44%) samples. Thirty-nine (89%) of the 44 positive samples reacted to all five leptospiral serovars tested.

Bovine respiratory syncytial virus (BRSV) is a very important pathogen of cattle and perhaps other ruminants. It is a major contributor to the incidence of respiratory tract disease in nursing beef and feedlot and dairy calves. The genome of respiratory syncytial viruses encodes 10 proteins translated from 10 unique mRNAs. The major glycoprotein (G), fusion protein (F), 1A protein and the 22K protein are components of the viral envelope. The nucleocapsid contains the nucleocapsid protein (N), the phosphoprotein (P), and the large protein (L). The matrix protein (M) forms a structural layer between the envelope and the nucleocapsid. Antibodies to all the structural proteins develop in convalescent calves. However, evidence suggests that immunity develops primarily as a result of the antigenic stimulus by the major glycoprotein G and the fusion glycoprotein F. It is known also that activated cytotoxic T cells interact with N and F protein antigens and helper T cells interact with N, F, and 1A protein antigens. With the exception of the major glycoprotein, the respective proteins of various respiratory syncytial viruses share major antigenic domains. Based on antigenic differences of the major glycoprotein, at least 3 subgroups of RSV are recognized; human A, human B, and bovine RSV. Indirect evidence suggests that a second subgroup of BRSV exists. However, we have identified only one BRSV subgroup based on our work with RNase mismatch cleavage analysis of the G protein gene from a limited number of strains. Furthermore, our data indicated that a caprine RSV isolate is closely related to the bovine strains, but an ovine isolate is not. The latter may constitute yet another subgroup of RSV. These data affect decisions on optimization of immunoprophylaxis since evidence suggests that protection against a homologous RSV subgroup virus is superior to that against a heterologous strain in immune subjects.

An unusual presentation of anaplastic large-cell (ALC) Ki-1 lymphoma is described, in which pulmonary involvement mimicked miliary tuberculosis. Lung involvement is uncommon in this type of lymphoma, and it is not clear from previous reports whether this was a presenting feature. Bone marrow involvement, rare in Ki-1 lymphoma, also was present in this case. Despite therapy skin involvement subsequently developed, and the patient died 3 months after presentation. Postmortem examination revealed lymphomatous involvement of the heart, liver, kidneys, stomach, and lymph nodes. This case highlights the need for awareness of ALC Ki-1 lymphoma particularly when it presents at uncommon extranodal sites.

Bovine viral diarrhea virus (BVDV) is an ubiquitous pathogen of cattle and has been reported in other ruminants. It is also frequently present in laboratory and biological materials as an adventitious agent. This virus is difficult to detect in some specimens, especially in the presence of specific antibody and when the virus is present in low concentrations. In this paper, we describe a single polymerase chain reaction (PCR) to amplify virus sequences from infected cell culture and a nested double PCR to detect small concentrations of several virus strains in sera. Total cellular RNA was extracted from cell cultures infected with the cytopathic strain 72 and noncytopathic strain 2724 of BVDV. Ten different genomic sequences along the length of the viral RNA ranging in size from 397 to 1,016 base pairs (bp) were successfully amplified by PCR. A 404-bp probe made from amplified product from the 3' end hybridized specifically with the RNA of several BVDV strains blotted on nylon filters. Viral RNA was extracted from serum and amplified using 2 sets of degenerate nested primers designed from the 3' end of the viral genome in a double PCR protocol. Double amplification of the viral sequences greatly enhanced the sensitivity of the detection of many strains present in serum. Advantages of using double PCR over single PCR and virus isolation is discussed. Bovine viral diarrhea virus (BVDV) is one of the most economically important viral pathogens in cattle. Its high prevalence is reflected by serologic surveys indicating infection rates of 50.90% in cattle. 1 It is a common adventitious contaminant of biological prod- ucts, fetal calf serum, and cell cultures; a consequence of the difficulty of detecting this organism in such ma- terials. The virus crosses the placenta very efficiently to the developing fetus and results in the birth of persistently infected animals that act as the main source of infection for other animals. Fetal calf serum, a common ingre- dient in many laboratory media, is obtained from fe- tuses in packing plants. A commercial lot of this prod- uct consists of pooled sera from many fetuses. Most of these products contain low concentrations of BVDV and BVDV antibodies. The low concentration of the virus in lots of fetal bovine sera and the presence of masking antibodies make detection of the virus by isolation of infectious virus or by immunoassay in such

A study was initiated to evaluate the feasibility of using pigs as an animal model to assess the risk of human viral infection from land application of treated wastewater. The model system consisted of three‐week‐old pigs and porcine enterovirus‐serotype 2 (PE2). Pigs were used because the porcine digestive tract and porcine enterovirus infections in pigs are similar to that of man. An oral challenge inoculation experiment was carried out to examine antibody production in pigs as a result of PE2 virus infection. Piglets free of antibody were intragastrically inoculated with 0, 100 or 100,000 CCID50 (50% cell culture infective dose) of PE2 virus. Serum was monitored to detect antibody to PE2 virus at 3, 7, 10 and 13 days post inoculation. By 13 days post inoculation all pigs challenge inoculated with as little as 100 CCID50 of PE2 virus had seroconverted. To evaluate the potential for using pigs to assess the risk of viral infection from contact with virus on lawns, piglets free of antibody to PE2...

We present two cases of May-Hegglin anomaly incidentally discovered in a patient and his brother during investigation of the patient for end-stage renal failure and workup for renal transplantation. Routine laboratory tests were performed and included a basically normal clotting profile. Ultrastructural studies of the May-Hegglin inclusions proved diagnostic, findings were compared with those of two similar granulocyte inclusion bodies, and nomenclature discrepancies that still exist in most references are again emphasized. The finding of the May-Hegglin anomaly in our patient appears to be incidental to the underlying renal disease. A successful renal transplant has been carried out in this patient. We now report on a patient and his brother in which the MHA was discovered during workup of the patient for end-stage renal failure and renal transplantation. No association between the underlying renal disease and the MHA could be demonstrated.

A dot blot hybridization assay was developed for use as a rapid screening test to detect bovine viral diarrhea virus (BVDV) in serum from infected cattle. A 1.1. kilobase cDNA, prepared from the BVDV genome, was molecularly cloned and used in this study. Insert cDNA was removed from the pUC9 plasmid vector by Pst-I restriction endonuclease digestion and purified from plasmid DNA by agarose electrophoresis and electroelution. The hybridization probe was prepared by nick translation in the presence of gamma dCT32P and labelled to a specific activity of 2 x 10(8) cpm/micrograms of DNA. Specificity was determined by dot blot hybridization of infected cell culture supernate from nine different BVDV strains. The probe hybridized equally with all strains of BVDV tested, which included four cytopathic and five noncytopathic strains of BVDV. Serum was collected from veal calves with respiratory tract disease, unthriftiness, anorexia, and/or poor conditions. Serum samples were treated with nonidet P40 detergent and denatured with formaldehyde and heat prior to application on 1.2 micron nylon membrane filters using a vacuum dot blot apparatus. Hybridization was done under relatively stringent conditions (50% formamide at 42 degrees C). A total of 141 serum samples from different calves were tested and of these samples, 55 (39%) were positive by dot blot hybridization for BVDV RNA. Eight calves (33%) out of 24, tested 3 to 4 weeks later, remained positive for BVDV RNA.

A commercial feline leukemia virus (FeLV) vaccine was evaluated in a natural exposure system. All kittens were negative for FeLV antigen on two enzyme-linked immunosorbent assay (ELISA) tests and one indirect immunofluorescence antibody (IFA) test before vaccination or exposure. Twenty-three kittens were vaccinated subcutaneously at nine and 12 weeks of age. The vaccinated kittens and 14 unvaccinated littermates were housed in an infected environment starting at 14 weeks. The kittens were exposed for 24 weeks by living in a large room with one feline leukemia virus-positive, asymptomatic adult cat for each five kittens. Sixty-four percent of the unvaccinated kittens and 70% of the vaccinated kittens became infected as determined by ELISA. Forty-three percent of unvaccinated kittens and 39% of vaccinated kittens died. There was no difference between the infection and mortality of vaccinated kittens that developed antibodies to anti-FeLV glycoprotein 70-envelope antigen and those that did not. Consideration should be given to evaluation of feline leukemia virus vaccines using "street" virus in a natural exposure system.

Nosocomial infections occurring in an intensive care unit (ICU) are commonly caused by aerobic Gram-negative bacilli or Staphylococcus aureus, which are frequently multi-resistant and difficult to treat and contribute significantly to the patients' morbidity in the ICU. Pefloxacin, with its wide range of antimicrobial activity, lack of serious side-effects and advantageous kinetics, is a useful drug for use in this group of critically ill patients. Pefloxacin has achieved a greater than 70% clinical cure rate and a microbiological response of over 80% in cases of nosocomial pneumonia in the ICU. Failure and superinfection has occurred with the development of resistance, particularly in Pseudomonas aeruginosa in a small number of cases, but this can be prevented by combination antimicrobial therapy. Serious side-effects, including confusion, psychiatric disturbance and other neurological abnormalities were rare and resolved on withdrawal of the drug. Drug interactions occur with cimetidine and theophylline but are usually not clinically relevant; significant interaction with warfarin occurs and the dose of warfarin needs careful adjustment. Pefloxacin is a valuable drug for use in bacteriologically proven sensitive infections and combination with aminoglycosides or beta-lactam agents should prevent the development of resistance.

Chronic renal failure has on occasion been referred to as a state of calcium toxicity. The aim of this study was to investigate the status of intracellular free Ca2+ in the neutrophils of chronic renal failure patients on maintenance haemodialysis treatment. Factors previously suggested to influence intracellular free Ca2+ were investigated including PTH levels, oxidative stress and recombinant human erythropoietin administration. The study involved 14 chronic renal failure patients on the haemodialysis programme of the Pretoria Academic hospital. Intracellular free Ca2+ and transmembrane Ca2+ fluxes were investigated by fluorescence spectrophotometry. Increases above control values were found in intracellular free Ca2+ (P-value 0.0242) and in the transmembrane Ca2+ flux upon fMLP stimulation (P-value 0.0002). The results showed significant differences in intracellular free Ca2+ between patients on rHuEPO and patients not on rHuEPO. The apparently rHuEPO-induced increase in intracellular free Ca2+ persisted in the presence of calcium channel blockers. No overt indications of oxidative stress could be detected by the antioxidant vitamin levels. It is concluded that factors other than those associated with uraemia, such as rHuEPO administration, might contribute to the often reported increase in intracellular free Ca2+ in these patients. Further studies to investigate the relationship between intracellular free Ca2+, rHuEPO and calcium channel blockers are suggested.

Virucidal efficacy was evaluated for four recently available disinfectants: chlorine dioxide, potassium peroxymonosulfate, a quaternary ammonium compound, and citricidal (grapefruit extract). Sodium hypochlorite (3%) and tap water were used as positive and negative controls respectively. Feline herpesvirus, feline calicivirus, and feline parvovirus were exposed to the manufacturers’ recommended dilutions of the evaluated disinfectants. Both chlorine dioxide and potassium peroxymonosulfate completely inactivated the three viruses used in this study. These disinfectants can aid in controlling nosocomial transmission of viruses with less of the deleterious effects of sodium hypochlorite. The quaternary ammonium compound evaluated in this study and citricidal were not effective against feline calicivirus and feline parvovirus.

The study was undertaken to determine the aetiology and prevalence of mastitis in hand-milked cows (n = 186) in two major Ethiopian dairies. The California Mastitis Test and culturing for bacteria revealed that 21.5% of the cows were clinically infected and 38.2% had subclinical mastitis. Most mastitis pathogens isolated from milk samples testing positive by the California Mastitis Test were Gram-positive cocci. Staphylococci constituted 57% of the isolates, of which the predominant cause of bovine mastitis was Staphylococcus aureus (40.5%). Other mastitis pathogens isolated include streptococci (16.5%), coliforms (9%) and corynebacteria (5%). Retrospective analysis of farm records indicated that mastitis was the second most important cause of culling and accounted for 27% of the cows removed from these two dairies.

Massive pulmonary gangrene is a rare complication of pneumonia, particularly in the postantibiotic era. We report two cases of community-acquired Streptococcus pneumoniae pneumonia in young patients with a background of heavy alcohol abuse, but no other preexisting disease, which failed to respond to appropriate antibiotic therapy and intensive care. In both, there was extensive unilateral involvement, with initial dense consolidation followed by cavitation, but the previously reported classic late radiologic feature of coalescence into a large cavity with free-floating slough was not seen. Owing to ongoing sepsis with the development of multiple organ failure and the obvious failure of appropriate medical therapy, both patients underwent pneumonectomy with a successful outcome. These cases serve to emphasize the role of surgery in the management of massive pulmonary gangrene.

Moraxella bovis pilus proteins, collected and purified from four strains of M. bovis, were cleaved with cyanogen bromide. Two major fragments were produced. Antisera were produced in rabbits to the pilin protein fragments and to whole uncleaved pili from these strains. Immunoblots of whole and cyanogen bromide-cleaved pilin were reacted with the homologous and heterologous antisera to whole pili and cleaved pilin. Antisera to whole pili reacted strongly with homologous pilin. Weaker and inconsistent reactions were detected with heterologous pilin. Antisera produced to cyanogen bromide-cleaved pilin proteins reacted strongly with homologous and heterologous pilin fragments and uncleaved pilin proteins. These findings demonstrate the presence of conserved antigenic determinants on pili from heterologous strains that are non-immunogenic in the intact pilus but are immunogenic after treatment with cyanogen bromide. Cyanogen bromide-treated pilus preparation might have potential as a vaccine because antibodies are induced against heterologous strains of M. bovis, whether these cross-reactive antibodies are protective remains to be determined.

Subgroup-specific peptide-based enzyme immunoassays from each respective G-glycoprotein of the ovine and the bovine respiratory syncytial virus (RSV) were developed to detect RSV-specific IgG responses in cattle. Antigenic peptides from the respective G-glycoprotein were identified from the extracellular central hydrophobic region (amino acids 158-189) located between 2 mucin-rich regions. These antigenic peptides identified by epitope mapping from each G-glycoprotein were synthesized and used to develop the subgroup- specific enzyme immunoassays. The negative cutoff for each enzyme immunoassay was established as the mean optical density of indirect immunofluorescent antibody-negative bovine sera plus 3 SDs. The sensitivity (82.9%) and specificity (100%) of the bovine enzyme immunoassay and the specificity (95.8%) of the ovine enzyme immunoassay were determined by comparison with indirect immunofluorescence (used as the ''gold standard''). The negative and positive predictive values were calculated for each assay. The presence of serum antibody to ovine RSV in cattle implies that this virus infects cattle and may contribute to the pathogenesis of bovine respiratory disease. Economic losses due to respiratory disease in the US cattle industry approximate $1 billion annually. 10 Respiratory syncytial virus (RSV) has been isolated from people (human RSV (HRSV)) and from several animal species, including cattle (bovine RSV (BRSV)), sheep (ovine RSV (ORSV)), and goats (cap- rine RSV). These viruses are members of the genus Pneumovirus in the family Paramyxoviridae. They are enveloped, single-stranded, nonsegmented, negative- sense RNA viruses. 11 The genome encodes 10 viral proteins: 1B, 1C, N, P, M, SH, M2, L, the major gly- coprotein (G), and the fusion (F) protein. 3,8 The G and F proteins are present in the membrane of infected cells and in the virus envelope. 16 The attachment pro- tein G has been the most variable antigen among viral strains. 2 The proposed 3-dimensional model for the G- glycoprotein of BRSV contains a hydrophobic globu- lar region (residues 158-189) bordered by 2 hydro- philic densely carbohydrate-coated mucin-like re- gions. 15 The G-glycoprotein gene from an ORSV strain has been cloned and sequenced and had greater homology to the BRSV gene (and its encoded protein) than to the HRSV gene (and its encoded protein). 2,4 However, the degree of base sequence differences between BRSV and ORSV suggests that 2 subgroups of an un- gulate RSV exist. 2,15 Recent RNase protection assays

Two different respiratory syncytial virus (RSV) radiolabeled probes were used to characterize the genetic heterogeneity of 25 ruminant RSV isolates by the ribonuclease protection assay. A 32P-radiolabeled antisense RNA probe was transcribed from cloned ovine and bovine RSV G glycoprotein genes and then hybridized with total RNA isolated from infected cells with various ruminant RSV isolates. The results of this study, along with previously published nucleotide sequence data of the ovine RSV G glycoprotein gene, suggest the presence of at least 2 ruminant RSV subgroups. One subgroup is represented by RSV isolated from respiratory disease outbreaks from calves and goats, and the other is represented by RSV isolated from sheep.

This study evaluates the recall of 100 patients after ICU admission. There was a wide spectrum of race, religion, occupation, and educational levels. The more common diagnoses included asthma, pneumonia, trauma, and adult respiratory distress syndrome. The average Acute Physiology and Chronic Health Evaluation (APACHE II) score was 12.3, and 68% of the patients were mechanically ventilated. The ICU atmosphere was described as friendly or relaxed by 94% of patients. Confidence in doctors and nurses was good. The most frequently reported unpleasant experiences were arterial blood gas sampling (48% of patients) and tracheal suctioning (30 of 68 ventilated patients). Only 6% of patients disliked ward rounds and discussion around the bedside. This study suggests that arterial lines or pulse oximetry could be used to avoid frequent arterial blood gas analyses and that tracheal suctioning should be performed with greater care. The need for better communication with patients is emphasized.

Feline infectious peritonitis (FIP) is a fatal disease of domestic and nondomestic felids caused by a feline coronavirus (FCV). It is a significant problem in catteries, multiple cat households, and shelters. 14,18 FIP can manifest as an effusive peritonitis and/or pleuritis, with a relatively short disease course ending in death. A protracted course with granulomatous lesions affecting multiple organs may occur, which also invariably progresses to death. 8,11,12 The FCVs are closely related and include two biotypes: those that are virulent and cause FIP and those that are avirulent. 7 The avirulent group, known as feline enteric coronaviruses (FECV), may be associated with mild enteric disease or subclinical infection in cats. 11,12 FCVs are also classified into serotypes 1 and 2 based on antigenicity. 7,12 Both serotypes contain virulent and avirulent biotypes, and FCVs within a serotype are indistinguishable in the laboratory. FCVs are ubiquitous, especially in environments such as catteries, where large numbers of cats are housed together and where the majority of cats are seropositive. 12 As a result, antemortem diagnosis for FIP is difficult because no detection assay sensitive enough and specific for the virus causing FIP is routinely available. 12 This problem is further compounded because consistent genetic differences between the virulent and avirulent biotypes of FCV have not been identified. 16 An assay has been developed using reverse transcription and a nested polymerase chain reaction (PCR) to detect FCV genomic material in a variety of biologic samples from cats. The genomic region targeted encompasses the 7a and 7b open reading frames (ORFs). This region, specifically that encoding the 7b ORF, may correlate with virulence.

Twenty captive red wolves (Canis rufus), including 16 intended for release into Great Smoky Mountains National Park, Cades Cove, Tennessee (USA), and four housed at Knoxville Zoological Gardens, Inc., Knoxville, Tennessee, were evaluated for immunologic response to vaccination between June 1994 and April 1995. Wolves were vaccinated with modified-live (MLV) canine distemper virus (CDV) and canine parvovirus type-2 (CPV2). Sera were collected, and immunofluorescent staining was performed for determination of immunoglobulin titers (CDV IgM, CDV IgG, and CPV2 IgG). A capture enzyme-linked immunosorbent assay was performed for validation purposes, to confirm the reactivity of our standard diagnostic reagents with red wolf serum. All wolves produced a measurable antibody response to CDV and CPV2 vaccination. Titers against CDV and CPV2 varied widely among individual wolves, but between-litter differences in mean titers were not significant. No consistent response between the degree of response to CDV versus CPV2 vaccination was observed in individual wolves. No differences were seen between IgG responses of pups vaccinated with univalent vaccines given concurrently or during alternating weeks. Pups had an IgG response to CDV and CPV2 vaccination as early as 9 wk of age. Mean post-vaccination IgG titers against CDV were at or above the level normally measured in vaccinated domestic dogs. Mean post-vaccination IgG titers against CPV2 were below the level normally measured in domestic dogs. Adult previously-vaccinated wolves had measurable CDV and CPV2 IgG titers more than 1 yr after vaccination, but did not have significant IgG titer increases after revaccination. We conclude that red wolves are capable of producing an antibody response after vaccination with commercial canine products but that their response to CPV2 vaccination was minimal. This response can be assayed using tests developed for domestic dogs.

Often persistent and primary postnatal infections with BVDV result in immunosuppression in cattle, thereby enhancing the vulnerability of the latter to secondary infections. The evidence for and nature of impaired immunity in these animals is reviewed. Our knowledge of the extent and nature of protective immunity induced by natural BVDV infections and vaccines is still in its infancy. Significant new information on the bovine immune response to BVDV antigens, however, has been identified in recent years. These data are reviewed and related to prospects for improved immunoprophylaxis against diseases caused by the virus.