An adventitious agent-free clonal cell line that is highly susceptible to foot -and-mouth disease virus.

Porcine LFBKαVß6 cells have been successfully used for diagnostics and propagation of all FMDV serotypes/subtypes. Unfortunately, after initial characterization, these cells showed contamination with bovine viral diarrhea virus (BVDV), a non-cytopathic adventitious agent. Persistent infection with BVDV could interfere with diagnostic tests and, also prevent consideration for other uses, i.e., vaccine production. In this study, we developed a three-prong methodology to completely remove BVDV from LFBKαVß6 cells. Combined treatment with siRNA against BVDV NS5A, porcine interferon alpha and ribavirin resulted in the elimination of BVDV, as determined by immunohistochemistry analysis, quantitative RT-PCR and RNA sequencing. Importantly, elimination of BVDV from LFBKαVß6 did not affect FMDV growth and plaque phenotype from different serotypes isolated and propagated in the clean cell line, newly named MGPK αVß6-C5. Additionally, isolation of FMDV from field oro-pharyngeal samples, was successful at the same sensitivity as in BVDV-contaminated LFBKαVß6 cells. Our results identified a direct method to efficiently eliminate BVDV from porcine cells without altering FMDV permissiveness, diagnostic value, or potential for use in vaccine production. Furthermore, these cells may provide an improved platform for diagnostics and propagation of other viruses of interest in the veterinary field and the virology community at large.

Coding-Complete Genome Sequences of Emerging Rabbit Hemorrhagic Disease Virus Type 2 Isolates Detected in 2020 in the United States.

Five rabbit hemorrhagic disease virus type 2 (RHDV2) coding-complete genome sequences were obtained from the livers of domestic and wild rabbits during the 2020 outbreak in the United States. These represent the first available RHDV2 sequences from the United States.

Genome Sequences of Vesicular Stomatitis Indiana Viruses from the 2019 Outbreak in the Southwest United States.

We report the genomes of three vesicular stomatitis Indiana virus (VSIV) isolates collected from naturally infected bovines in Wyoming and Colorado during the 2019 outbreak in the United States. These genomes support molecular diagnostic efforts and provide data on the spread and ecology of VSIV in the United States.

Intranasal immunization of guinea pigs with an immunodominant foot-and-mouth disease virus peptide conjugate induces mucosal and humoral antibodies and protection against challenge.

Guinea pigs immunized intranasally with a keyhole limpet hemocyanin-linked peptide, corresponding to the prominent G-H loop of the VP1 protein of foot-and-mouth disease virus, raised substantial levels of antipeptide and virus-neutralizing antibodies in sera and of peptide-specific secretory immunoglobulin A in nasal secretions. In groups of animals immunized intranasally without adjuvant, 86 percent were fully protected upon challenge with homotypic virus. Surprisingly, animals given the peptide conjugates plus the mucosal adjuvant cholera toxin were afforded only partial protection in that primary lesions were observed in most animals, although spread to other feet was prevented. These results indicate that intranasal inoculation with the peptide offers a potential route of vaccination against foot-and-mouth disease and may be useful for eliciting protection in the upper respiratory tracts of susceptible animals.

The use of a permanent dermal allograft in full-thickness burns of the hand and foot: a report of three cases.

The standard method of grafting deep, thermal hand-and-foot burns with either full-thickness sheet grafts or narrowly meshed, thick, split-thickness skin grafts not only leaves a deep donor site, but also becomes complicated by infection, hypertrophic scarring, blistering, and hyper- or hypopigmentation. The availability now of an acellular, immunologically inert dermal transplant (AlloDerm; LifeCell Corp., The Woodlands, Texas) allows the successful use of ultrathin autografts while maximizing the amount of dermis delivered to the wound site. These autografts leave thin donor sites that heal faster and with fewer complications. This case report describes the use of AlloDerm dermal grafts on three patients with full-thickness burns of the distal extremities. Grafts were applied to the hand in two cases and the dorsum of the foot in the third. Range of motion, grip strength, fine motor coordination, and functional performance were quantitatively evaluated. As demonstrated by these patients, cosmetic and functional results were considered good to excellent after the use of AlloDerm grafts with thin autografts.

Serious silver sulphadiazine and mafenide acetate dermatitis.

Infrequently reported, serious allergic reactions to topical antimicrobial agents used in the treatment of burn injuries are a potential source of confusion. To avoid misdirected therapy, an understanding of the manifestations of such reactions is important. Two recent cases of serious allergic reactions, one to silver sulphadiazine, one to mafenide acetate, are presented and the literature is reviewed.

Nonoperative management of blunt hepatic injuries: safe at any grade?

Nonoperative management of blunt hepatic injury (BHI) has become more widely accepted. A prospective trial was undertaken to test the belief that clinical state could identify the patients with BHI confirmed by computed tomography (CT) who could be safely managed without a surgical operation. Patients were excluded from nonoperative management only if they manifested hemodynamic instability, the presence or suspicion of any other injury requiring laparotomy, or would be unavailable for controlled monitoring. Of 60 patients treated for BHI, 30 were managed nonoperatively. The 30 who had laparotomies served as a comparative group. The groups were statistically similar in age, sex, and Injury Severity Score (ISS). The group managed nonoperatively had significantly more severe BHI. There were no deaths or delayed laparotomies in the nonoperative management group. The groups had similar ICU and total hospital stays when analyzed as independent variables or with control for BHI grade and ISS. Transfusion requirements were significantly lower for the nonoperative management group when analyzed independently or when controlled for BHI grade, ISS, and the number of non-abdominal injuries. Nineteen (63%) patients managed nonoperatively were followed until their CT scans showed complete resolution. None had complications. We conclude that nonoperative management of BHI is a safe and effective technique applicable to hemodynamically stable patients who lack other indications for laparotomy and who can be adequately monitored.

The efficacy of barbiturate coma in the management of uncontrolled intracranial hypertension following neurosurgical trauma.

The purpose of this study was to evaluate the role of barbiturate therapy as an adjunctive treatment for control of intracranial hypertension when conventional methods failed. To this end, a retrospective chart review was conducted on 21 neurosurgical trauma patients with uncontrolled intracranial pressure (ICP) admitted to a trauma/intensive care unit. In this patient population, the overall mortality was 48%. Control of ICP was achieved in 67% of patients. The survival of patients experiencing ICP control with barbiturate coma was better than those patients who failed therapy (71% vs 14%, p = 0.021). Thus, in a subgroup of neurosurgical trauma patients who are refractory to conventional management of elevated ICP, barbiturates appear to improve survival, suggesting that this therapy has an important role in the management of neurotrauma patients.

Comparison of conventional mechanical ventilation and high-frequency ventilation. A prospective, randomized trial in patients with respiratory failure.

Acute respiratory failure (ARF) following trauma or sepsis has a mortality rate of 50% to 85%. The mainstays of treatment are mechanical ventilation and positive end-expiratory pressure (PEEP). In the past decade, many reports have claimed superiority of high frequency ventilation (HFV) in the treatment of ARF. We structured a prospective randomized trial of HFV versus conventional mechanical ventilation (CMV) in the treatment of acute respiratory failure. All patients admitted to the Surgical Intensive Care Unit (SICU) were eligible for the study. On admission patients identified for being at risk of developing acute respiratory failure were randomized to receive either HFV or CMV. Patients were treated to the same therapeutic endpoint (pH greater than 7.35, PaCO2 35 to 45 torr, PaO2/FIO2 greater than 225). Daily ventilatory support, fluid and drug requirements, and cardiopulmonary variables were recorded. One hundred thirteen patients were entered into the study. Of these, 100 completed the study (HFV n = 52, CMV n = 48) and 60 developed acute respiratory failure (HFV n = 32, CMV n = 28). Patients on HFV reached the therapeutic endpoint at a lower level of continuous positive airway pressure and mean airway pressure; however there were no differences in mortality, SICU days, hospital days, incidence of barotrauma, number of blood gases, or cardiovascular interventions. This report suggests that HFV offers no concrete advantages over CMV when applied in a prospective fashion for the treatment of acute respiratory failure.

Cardiopulmonary effects of pressure support ventilation.

Pressure support ventilation (PSV) is a newer mode of ventilatory support that augments the patient's spontaneous inspirations to a preselected peak inspiratory pressure. We studied the effects of adding low levels of PSV (5 to 10 cm H2O) in conjunction with intermittent mandatory ventilation (IMV) on 15 patients who required mechanical ventilation for flail chest and pulmonary contusion. Patients were selected for the study if, during weaning from IMV, the following criteria were met: (1) a PaCO2 level greater than 45 mm Hg, (2) a spontaneous respiratory rate (RR) greater than 30 breaths per minute, (3) a minute ventilation (VE) greater than 9.0 L/min, and (4) spontaneous tidal volumes (VT) of less than 2 mL/kg. The PSV was added to the IMV at a level that augmented spontaneous VT to greater than 4 mL/kg. An average of 9 +/- 3 cm H2O of pressure support resulted in a fall in the level of PaCO2 (50 +/- 4 to 43 +/- 5 mm Hg), spontaneous RR (36 +/- 5 to 16 +/- 3 breaths per minute), VE (12 +/- 2 to 8.4 +/- 1.5 L/min), and dead space-tidal volume ratio from (0.68 +/- 0.1 to 0.47 +/- 0.05). Mean airway pressure and PaO2 both increased, but these changes were not statistically significant. Oxygen consumption was also unchanged. These results suggest that in patients who are difficult to wean due to respiratory muscle fatigue (characterized by increasing RR and decreasing VT), PSV normalizes lung volumes, improves ventilation, and may expedite the weaning process.