Colorectal surgical outcomes following implementation of an enhanced recovery after surgery programme in Cape Town.

BACKGROUND: Colorectal surgery is commonly performed for benign and malignant colorectal disease. The aim of this study was to describe length of stay (LOS), complications and its associated factors in patients undergoing elective colorectal surgery following implementation of an enhanced recovery after surgery (ERAS) programme in South Africa (SA). METHODS: Socio-demographic, pre- intra- and postoperative clinical details and compliance to the ERAS guidelines were recorded in all patients undergoing colorectal surgery in a private practice in Cape Town, SA. Means and standard deviations or medians and interquartile range (IQR), as appropriate, were used to describe continuous variables and frequencies and percentages for categorical variables. Bivariate and multivariate analyses using linear regression of log transformed LOS and logistic regression for development of complications were performed. RESULTS: Between 2015 and 2019, 457 patients had elective colorectal surgical procedures. The median LOS was 5 days (IQR 3-7). Pre- and intraoperative compliance was 92% and 86% respectively. In total, 203 (44%) patients developed 346 complications, of which 61% were minor. On bivariate analysis, increased intraoperative compliance was associated with a significant decrease in LOS (coefficient [ß] = 0.987, 95% confidence interval [CI] 0.984-0.991) and complications (odds ratio [OR] 0.457, 95/5 CI 0.266-0.787). For every additional 30 minutes of theatre time, irrespective of type of procedure, LOS increased by 8% and complications by 12%. On multivariate analysis, laparoscopic compared to open surgery was also associated with a shorter LOS (exp [ß] = 0.667, 95% CI 0.580-0.767 p < 0.001) and reduced complications (OR 0.457, 95% CI 0.266-0.787). CONCLUSION: Our results show that high compliance to the ERAS guidelines is possible in the private sector in SA and that a significant reduction in LOS can be achieved without placing the patient at a higher risk of complications.

Serological responses of cattle inoculated with inactivated trivalent foot-and-mouth disease vaccine at the wildlife-livestock interface of the Kruger National Park, South Africa.

Foot-and-mouth disease (FMD) virus is economically one of the world's most important animal pathogens, which can be responsible for losses in livestock trade, as well as frequent and highly disruptive large-scale epidemics. The control of FMD in southern Africa typically includes vaccination of cattle with a trivalent or bivalent vaccine preparation. The objective of this study was to determine the level and duration of the antibody responses conferred by the current FMD vaccination programme in cattle at the western boundary of the Kruger National Park (KNP) in South Africa. Two hundred and eighty-three cattle from four communal dip tanks were longitudinally sampled after vaccination using an inactivated trivalent FMD vaccine (South African Territories (SAT) 1, SAT 2 and SAT 3). Blood samples were collected fortnightly over four months and antibodies were measured using a liquid-phase blocking ELISA. Only 5%, 43%, and 16% of enrolled cattle had evidence of pre-existing antibody responses to the three SAT viruses at the beginning of the study (≥1.6 log10 titre for SAT 1-3 respectively), which was 7-12 months after the last vaccination campaign. However, 14 days after vaccination this proportion increased to between 66% and 93%, with SAT 2 having the highest proportion. Young animals (<1 year old) tended to have higher predicted baseline antibody levels that peaked by 14 days. Positive serological responses were transient and by 56 days post-vaccination antibody levels begun to decline below the threshold of 1.6 log10 titre. Predicted peak antibody levels only consistently reached 2.0 log10 for SAT 2. Serological responses for SAT 2 tended to be longer, but in most cases the duration of antibody levels was short-lived. More research is necessary to determine the reasons for the limited duration of antibody responses, especially among younger cattle, in order to achieve more effective prophylactic vaccination.

Development and validation of a foot-and-mouth disease virus SAT serotype-specific 3ABC assay to differentiate infected from vaccinated animals.

The effective control of foot-and-mouth disease (FMD) requires sensitive, specific and rapid diagnostic tools. However, the control and eradication of FMD in Africa is complicated by, among other factors, the existence of five of the seven FMD virus (FMDV) serotypes, including the SAT-serotypes 1, 2 and 3 that are genetically and antigenically the most variable FMDV serotypes. A key diagnostic assay to enable a country to re-gain its FMD-free status and for FMD surveillance, is the 3ABC or the non-structural protein (NSP) enzyme-linked immunosorbent assay (ELISA). Although many kits are available to detect 3ABC antibodies, none has been developed specifically for the variable SAT serotypes. This study designed a SAT-specific NSP ELISA and determined whether this assay could better detect NSP-specific antibodies from FMDV SAT-infected livestock. The assay's performance was compared to validated NSP assays (PrioCheck®-NSP and IZSLER-NSP), using panels of field and experimental sera, vaccinated and/or infected with FMDV SAT1, SAT2 or SAT3. The sensitivity () of the SAT-NSP was estimated as 76% (70%, 81%) whereas the specificity was 96% (95%, 98%) at a 95% confidence interval. The sensitivity and specificity were comparable to the commercial NSP assays, PrioCheck®-NSP (82% and 99%, respectively) and IZSLER-NSP (78% and 98%, respectively). Good correlations were observed for all three assays.

Serological evidence of vaccination and perceptions concerning Foot-and-Mouth Disease control in cattle at the wildlife-livestock interface of the Kruger National Park, South Africa.

Communal livestock farming areas adjoining the Greater Kruger National Park Area within South Africa are part of the Foot-and-mouth disease (FMD) Protection Zone with Vaccination due to the proximity to wildlife reservoirs. FMD and its control affect the productivity of resource-poor farmers who often depend on livestock for their livelihoods. A cross-sectional study was performed with the objectives to evaluate the perceptions of farmers concerning FMD control, estimate the proportion of cattle with presumed protective antibody titres against FMD, as well as the proportion of herds with adequate herd immunity at the wildlife-livestock interface within Mpumalanga Province. One hundred and four farmers were interviewed with 73% (76/104) being cattle owners and the remainder hired cattle herders. The majority of respondents (79%, 82/104) reported a high level of satisfaction with the current animal health programmes in general. The educational level of the respondents varied by satisfaction level: the median (interquartile range; IQR) education level was standard 9 (2-12) for non-satisfied respondents, standard 3 (0-6) for little satisfied and standard 7 (2-11) for very satisfied respondents (P=0.036). Animals are not always treated at FMD inspections points, but satisfied respondents were more likely to seek veterinary assistance (P=0.001). The majority of respondents (92%, 96/104) identified the African buffalo (Syncerus caffer) as a risk factor for FMD outbreaks. Liquid-phase blocking ELISA antibody titres ≥1.6log10 were used to indicate positive serology secondary to FMD vaccination. At the time of sampling and relative to this threshold, 23% (95% confidence interval (CI): 12%-34%) of the sampled cattle had positive serology to SAT-1, 41% (95%CI: 33%-48%) to SAT-2 and 29% (95%CI: 19%-39%) to SAT-3. The median (IQR) time between the previous vaccination and sampling was 189 (168-241) days. The sampled cattle had a longer inter-vaccination interval as scheduled by state veterinary services and antibody levels were low at the time of the study. The majority of respondents expressed high satisfaction with the currently applied FMD vaccination programme, which provides an opportunity for progressive adaption of animal health programmes within the study area.

Determination of common genetic variants within the non-structural proteins of foot-and-mouth disease viruses isolated in sub-Saharan Africa.

The non-structural proteins of foot-and-mouth disease virus (FMDV) are responsible for RNA replication, proteolytic processing of the viral polyprotein precursor, folding and assembly of the structural proteins and modification of the cellular translation apparatus. Investigation of the amino acid heterogeneity of the non-structural proteins of seventy-nine FMDV isolates of SAT1, SAT2, SAT3, A and O serotypes revealed between 29 and 62% amino acid variability. The Leader protease (L(pro)) and 3A proteins were the most variable whilst the RNA-dependent RNA polymerase (3D(pol)) the most conserved. Phylogeny based on the non-structural protein-coding regions showed separate clusters for southern African viruses for both the L(pro) and 3C protease (3C(pro)) and sequences unique to this group of viruses, e.g. in the 2C and 3C(pro) proteins. These groupings were unlike serotype groupings based on structural protein-coding regions. The amino acid substitutions and the nature of the naturally occurring substitutions provide insight into the functional domains and regions of the non-structural proteins that are critical for structure-function. The L(pro) of southern African SAT type isolates differed from A, O and SAT isolates in northern Africa, particularly in the auto-processing region. Three-dimensional structures of the 3C protease (3C(pro)) and 3D(pol) showed that the observed variation does not affect the enzymatic active sites or substrate binding sites. Variation in the 3C(pro) cleavage sites demonstrates broad substrate specificity.

Predicting People's Intention to Donate Their Body to Medical Science and Research.

Predictors of people's intention to register with a body bequest program for donating their deceased body to medical science and research were examined using standard theory of planned behavior (TPB) predictors (attitude, subjective norm, perceived behavioral control) and adding moral norm, altruism, and knowledge. Australian students (N = 221) at a university with a recently established body bequest program completed measures of the TPB's underlying beliefs (behavioral, normative, and control beliefs) and standard and extended TPB predictors, with a sub-sample reporting their registration-related behavior 2 months later. The standard TPB accounted for 43.6%, and the extended predictors an additional 15.1% of variance in intention. The significant predictors were attitude, subjective norm, and moral norm, partially supporting an extended TPB in understanding people's body donation intentions. Further, important underlying beliefs can inform strategies to target prospective donors.

Impact of a postdischarge smoking cessation intervention for smokers admitted to an inpatient psychiatric facility: a randomized controlled trial.

INTRODUCTION: Persons with a mental disorder smoke at higher rates and suffer disproportionate tobacco-related burden compared with the general population. The aim of this study was to determine if a smoking cessation intervention initiated during a psychiatric hospitalization and continued postdischarge was effective in reducing smoking behaviors among persons with a mental disorder. METHODS: A randomized controlled trial was conducted at an Australian inpatient psychiatric facility. Participants were 205 patient smokers allocated to a treatment as usual control (n = 101) or a smoking cessation intervention (n = 104) incorporating psychosocial and pharmacological support for 4 months postdischarge. Follow-up assessments were conducted at 1 week, 2, 4, and 6 months postdischarge and included abstinence from cigarettes, quit attempts, daily cigarette consumption, and nicotine dependence. RESULTS: Rates of continuous and 7-day point prevalence abstinence did not differ between treatment conditions at the 6-month follow-up; however, point prevalence abstinence was significantly higher for intervention (11.5%) compared with control (2%) participants at 4 months (OR = 6.46, p = .01). Participants in the intervention condition reported significantly more quit attempts (F[1, 202.5] = 15.23, p = .0001), lower daily cigarette consumption (F[4, 586] = 6.5, p < .001), and lower levels of nicotine dependence (F[3, 406] = 8.5, p < .0001) compared with controls at all follow-up assessments. CONCLUSIONS: Postdischarge cessation support was effective in encouraging quit attempts and reducing cigarette consumption up to 6 months postdischarge. Additional support strategies are required to facilitate longer-term cessation benefits for smokers with a mental disorder.

Genetic heterogeneity in the leader and P1-coding regions of foot-and-mouth disease virus serotypes A and O in Africa.

Genetic information regarding the leader (L) and complete capsid-coding (P1) region of FMD serotype A and O viruses prevalent on the African continent is lacking. Here, we present the complete L-P1 sequences for eight serotype A and nine serotype O viruses recovered from FMDV outbreaks in East and West Africa over the last 33 years. Phylogenetic analysis of the P1 and capsid-coding regions revealed that the African isolates grouped according to serotype, and certain clusters were indicative of transboundary as well as intra-regional spread of the virus. However, similar analysis of the L region revealed random groupings of isolates from serotypes O and A. Comparisons between the phylogenetic trees derived from the structural coding regions and the L region pointed to a possibility of genetic recombination. The intertypic nucleotide and amino acid variation of all the isolates in this study supported results from previous studies where the externally located 1D was the most variable whilst the internally located 1A was the most conserved, which likely reflects the selective pressures on these proteins. Amino acids identified previously as important for FMDV structure and functioning were found to be highly conserved. The information gained from this study will contribute to the construction of structurally designed FMDV vaccines in Africa.

The importance of FMDV localisation in lymphoid tissue.

Foot-and-mouth disease virus, a highly contagious pathogen that can cause lameness, low weight and decreased milk production, is a scourge of agricultural livestock around the world. Although the acute phase of infection is rarely fatal, infection may persist in animals that have apparently recovered, creating a viral reservoir that some fear could contribute to the spread of disease. We have used an array of molecular techniques to search for traces of virus in tissues from the mouths and throats of infected cattle. In a carefully controlled study, we have found evidence of intact, non-replicating virus particles trapped by follicular dendritic cells within the germinal centres of lymph nodes. Strikingly, virus was present for up to 38 days post infection, even though it was undetectable in surrounding tissues. The retention of intact virus within germinal centres is likely to have a role in stimulating the long lasting immune response that is characteristic of viral infections. Our data suggests that this capture may also be responsible for preserving intact viruses capable of infecting susceptible cells as they come into contact with germinal centres. African buffalo (Syncerus caffer) are typically infected with all three South African Territories types of FMDV by 2 years of age and these viruses can be transmitted to farmed livestock. Buffalo harbour persistent virus in greater amounts and for longer periods than cattle and thus provided us with further opportunities to define the sites of viral localisation.

Foot-and-mouth disease marker vaccine: cattle protection with a partial VP1 G-H loop deleted virus antigen.

Contrary to the dogma that the VP1 G-H loop is essential for FMD vaccine efficacy, it has been previously shown that foot-and-mouth disease 146s antigen containing heterologous VP1 G-H loops confers complete protection in pigs and cattle. Moreover, serological evaluation of cattle vaccinated with an antigen lacking a large proportion of the VP1 G-H loop indicated that these animals should be protected against infection with FMD. Absence of this loop provides opportunity for the development of an FMD negative marker vaccine, allowing infection to be detected by antibodies against this missing region. Cattle vaccinated with this negative marker vaccine were fully protected following virus challenge 28 days post vaccination as determined by the absence of generalised lesions on their feet. Furthermore, use of our improved differentiation ELISA identified animals exposed to infection as early as 7 days post-challenge. We thus demonstrate, for the first time, the ability of this FMD negative marker vaccine to fully protect cattle from experimental challenge and rapidly distinguish animals that are subsequently exposed to infection.

Predicting antigenic sites on the foot-and-mouth disease virus capsid of the South African Territories types using virus neutralization data.

Foot-and-mouth disease virus (FMDV) outer capsid proteins 1B, 1C and 1D contribute to the virus serotype distribution and antigenic variants that exist within each of the seven serotypes. This study presents phylogenetic, genetic and antigenic analyses of South African Territories (SAT) serotypes prevalent in sub-Saharan Africa. Here, we show that the high levels of genetic diversity in the P1-coding region within the SAT serotypes are reflected in the antigenic properties of these viruses and therefore have implications for the selection of vaccine strains that would provide the best vaccine match against emerging viruses. Interestingly, although SAT1 and SAT2 viruses displayed similar genetic variation within each serotype (32 % variable amino acids), antigenic disparity, as measured by r(1)-values, was less pronounced for SAT1 viruses compared with SAT2 viruses within our dataset, emphasizing the high antigenic variation within the SAT2 serotype. Furthermore, we combined amino acid variation and the r(1)-values with crystallographic structural data and were able to predict areas on the surface of the FMD virion as antigenically relevant. These sites were mostly consistent with antigenic sites previously determined for types A, O and C using mAbs and escape mutant studies. Our methodology offers a quick alternative to determine antigenic relevant sites for FMDV field strains.

Interprofessional education in clinical practice: not a single vaccine.

In increasingly complex health service environments, the quality of teamwork and co-operation between doctors, nurses and allied health professionals, is 'under the microscope'. Interprofessional education (IPE), a process whereby health professionals learn 'from, with and about each other', is advocated as a response to widespread calls for improved communication and collaboration between healthcare professionals.

Mosaic structure of foot-and-mouth disease virus genomes.

The results of a simple pairwise-scanning analysis designed to identify inter-serotype recombination fragments, applied to genome data from 156 isolates of Foot-and-mouth disease virus (FMDV) representing all seven serotypes, are reported. Large numbers of candidate recombinant fragments were identified from all parts of the FMDV genome, with the exception of the capsid genes, within which such fragments are infrequent. As expected, intertypic fragment exchange is most common between geographically sympatric FMDV serotypes. After accounting for the likelihood of intertypic convergence in highly conserved parts of the FMDV genome, it is concluded that intertypic recombination is probably widespread throughout the non-structural genes, but that recombination over the 2B/C and 3B/C gene boundaries appears to be less frequent than expected, given the large numbers of recombinant gene fragments arising in these genes.

A second RGD motif in the 1D capsid protein of a SAT1 type foot-and-mouth disease virus field isolate is not essential for attachment to target cells.

The amino acid sequence motif Arg-Gly-Asp (RGD), located in the surface-exposed betaG-betaH loop of the 1D protein of different serotypes and subtypes of foot-and-mouth disease virus (FMDV), is highly conserved and participates in binding of FMDV to susceptible cells. Previous sequence analyses of the 1D-encoding region of a FMDV serotype SAT1 field isolate from Namibia (NAM/307/98) indicated the presence of a second RGD motif upstream of the conserved betaG-betaH loop RGD. The role of these RGD sequences in virus infection was investigated by mutating the betaG-betaH loop RGD to a KGE tripeptide, using a genome-length infectious chimeric cDNA clone. Although the infectivity of the derived mutant viruses for baby hamster kidney cells (BHK-21) was lost, subsequent replacement of the KGE sequence with RGD in the mutant cDNA clone led to recovery of infectious viruses. Furthermore, viral RNA replication could be demonstrated with the genetically engineered mutant and non-mutant viruses. The presence of virus particles in the transfected cells could be also demonstrated by electron microscopy. These results demonstrate that, in contrast to the betaG-betaH loop RGD motif, the second RGD sequence in the capsid protein 1D of NAM/307/98 does not function as a ligand for receptor binding in BHK-21 cells.

Risk factors for chronic insomnia following hospitalization.

AIM: This paper reports a study whose purpose was to determine whether there is an increase in the incidence of chronic insomnia following hospitalization and, if so, to identify patients at risk. BACKGROUND: The consequences of difficulty sleeping in hospital have received scant attention from clinicians or researchers. Implicit in this lack of interest is the assumption that difficulty in sleeping is a transient reaction to hospitalization that will resolve on discharge, an assumption not empirically supported. It has been argued that in susceptible people this type of temporary disruption to sleep can be the catalyst for the development of chronic insomnia. METHOD: Established sleep and depression rating instruments were used to monitor the sleep of 57 cardiac and 29 orthopaedic patients after elective surgery (n = 86), recruited through a hospital preadmission clinic. RESULTS: Preadmission chronic insomnia of 10% was consistent with general population prevalence estimates of 6-12%. Three months after discharge the incidence had almost doubled to 19%. Sixty-one per cent of this variance could be explained by hyperarousal, sleep hygiene issues, and dysfunctional cognitions about sleep. Depression was found to be a salient predictor but not an independent risk factor. Age, sex, and hospital-related data, such as score for difficulty sleeping in hospital, proved to be statistically insignificant. CONCLUSIONS: The results support the role of hyperarousal and dysfunctional sleep attitudes and behaviours as stronger predictors of chronic insomnia than patient demographics or environmental issues. Given that most of the patients were ambivalent about how they slept in hospital, with high satisfaction (71%) in the presence of significant disruption (63%), preadmission sleep education given to these patients prior to admission potentially contributed to the development of more realistic expectations of the quality of in-hospital sleep.

Hepatic osteodystrophy in rats results mainly from portasystemic shunting.

BACKGROUND AND AIMS: In chronic liver disease, bone disease frequently develops. The contributions of the different features of liver disease such as parenchymal inflammation, portal hypertension, and portasystemic shunting on bone metabolism have not been systematically studied. The aim of this study was to identify the features of liver disease contributing to bone disease using rat models. METHODS: Parenchymal liver disease was induced by carbon tetrachloride administration, portal hypertension by partial portal vein ligation, and portasystemic shunting by end to side anastomosis of the portal vein to the inferior vena cava. Normal and sham operated surgical animals served as controls. Serum calcium, 25-hydroxy vitamin D (25-OH vit D), and osteocalcin levels, and urinary deoxypyridinoline excretion were analysed. Testosterone and oestradiol levels were determined in male and female rats, respectively. Interleukin 1, interleukin 6, and tumour necrosis factor alpha (TNF-alpha) were determined in serum. Bone density was measured in all groups and in addition, in the surgical groups, histomorphometry was performed on undecalcified specimens of the proximal tibia. The calcium content of the femurs, removed at termination and ashed, was determined. RESULTS: Early parenchymal disease and portal hypertension did not affect bone metabolism or body mass. Portasystemic shunting increased bone resorption, decreased bone formation, bone density, and trabecular bone volume which were commensurate with a reduction in body mass. TNF-alpha levels were elevated and testosterone levels were low in male portasystemic shunted rats. CONCLUSIONS: Portasystemic shunting in the rat adversely affects bone metabolism as part of a generalised catabolic state where high TNF-alpha and low testosterone and 25-OH vit D levels may play a role.

Evaluation of a novel heminested PCR assay based on the phosphoglucosamine mutase gene for detection of Helicobacter pylori in saliva and dental plaque.

A novel heminested PCR protocol was developed for the specific detection of Helicobacter pylori at low copy numbers. A set of primers specific for the phosphoglucosamine mutase gene (glmM) of H. pylori produced a 765-bp fragment that was used as template for the heminested primer pair delineating a 496-bp fragment. By using agarose gel electrophoresis for detection of the heminested PCR-amplified products, amplification of H. pylori genomic DNA was achieved at concentrations as low as 0.1 pg, equivalent to 5 x 10(2) bacteria. A study was subsequently undertaken to evaluate the heminested PCR for detection of H. pylori in dental plaque and saliva. Specimens collected from 58 individuals were cultured, and PCR was subsequently performed on the oral cultures. Identification of H. pylori in the same series of saliva and dental plaque specimens was carried out with PCR using a primer pair specific for the H. pylori urease B gene and by the heminested PCR assay. The identity of the amplified products was confirmed by DNA sequencing. Our results demonstrate that the heminested PCR assay was specific for detection of H. pylori, yielding no false-positive results, and that H. pylori had a low prevalence (approximately 3%) in specimens obtained from the oral cavity.

Expression of the major core structural proteins VP3 and VP7 of African horse sickness virus, and production of core-like particles.

The genome segments encoding the seven structural proteins of African horse sickness virus (AHSV), including the largest coding for VP1, were cloned and sequenced. Analysis of the VP1 sequence supports the putative identity of this protein as an RNA polymerase. The genes encoding the two major core proteins, VP3 and VP7, were also cloned and expressed by both in vitro translation and by means of recombinant baculoviruses. Co-infection of insect cells with VP3 and VP7 recombinant baculoviruses resulted in the intracellular formation of multimeric particles with a diameter of 72 nm, which structurally resembled authentic AHSV cores (core like particles: CLP). The complete genome of AHSV has now been cloned and sequenced.

Characterization of two African horse sickness virus nonstructural proteins, NS1 and NS3.

Each of the ten segments of the African horse sickness virus (AHSV) genome encodes at least one viral polypeptide. This report focuses on the nonstructural proteins NS1 and NS3, which are encoded by genome segments 5 and 10 respectively. The NS1 protein assembles into tubular structures, which are characteristically produced during orbivirus replication in infected cells. NS1 expressed by a recombinant baculovirus in Sf9 cells also forms tubules, which were analysed electron microscopically. These tubules had an average diameter of 23 +/- 2 nm, which is less than half the width of the corresponding bluetongue virus (BTV) tubules. They were also more fragile at high salt concentrations or pH. The cytotoxic effects produced by NS3 were examined by constructing of mutated versions and expressing them in insect cells. Substitution of amino acids 76-81 in a conserved region (highly conserved amongst all AHSV NS3 proteins, as well as other orbiviruses) with similar amino acids, did not influence the cytotoxicity of the mutant protein. However, mutation of four amino acids, from hydrophobic to charged amino residues, (aa 165-168) in a predicted transmembrane region of NS3, largely abolished its cytotoxic effect. It is considered likely that the mutant protein is unable to interact with cellular membrane components, thereby reducing its toxicity.

Characterization of tubular structures composed of nonstructural protein NS1 of African horsesickness virus expressed in insect cells.

The characteristic tubules that are produced during the orbivirus infection cycle are composed of a major viral nonstructural protein, NS1. To characterize the NS1 gene and gene product of African horsesickness virus (AHSV), a full-length cDNA copy of the NS1 gene of AHSV-6 was cloned and the nucleotide sequence determined. NS1 was highly conserved within the AHSV serogroup with between 95-98% conservation of amino acids among NS1 of AHSV-6, AHSV-4 and AHSV-9. The structure of AHSV NS1 tubules was investigated by in vitro translation of the AHSV-6 NS1 gene followed by expression of the gene in insect cells. The NS1 protein assembled in tubular structures with a diameter of approximately 23 nm and lengths of up to 4 microns. The absence of a ladder-like structure and lower sedimentation value of AHSV NS1 tubules clearly distinguished them from those of bluetongue virus.