OBJECTIVE

The Longitudinal Assessment of Manic Symptoms (LAMS) study was designed to investigate phenomenology and establish predictors of functional outcomes in children with elevated manic symptoms. The purpose of this series of analyses was to determine whether the participants demonstrated different trajectories of parent-reported manic and biphasic symptoms over the first 24 months of follow-up and to describe the clinical characteristics of the trajectories.

METHODS

The 707 participants were initially aged 6-12 years and ascertained from outpatient clinics associated with the four university-affiliated LAMS sites. There were 621 children whose parents/guardians' ratings scored ≥ 12 on the Parent General Behavior Inventory-10-item Mania Form (PGBI-10M) and a matched random sample of 86 children whose parents/guardians' ratings scored ≤ 11 on the PGBI-10M. Participants were seen every six months after the baseline and their parents completed the PGBI-10M at each visit.

RESULTS

For the whole sample, manic symptoms decreased over 24 months (linear effect B = -1.15, standard error = 0.32, t = -3.66, p < 0.001). Growth mixture modeling revealed four unique trajectories of manic symptoms. Approximately 85% of the cohort belonged to two classes in which manic symptoms decreased. The remaining ~15% formed two classes (high and rising and unstable) characterized by the highest rates of diagnostic conversion to a bipolar disorder (all p-values < 0.001).

CONCLUSIONS

Outcomes are not uniform among children with symptoms of mania or at high risk for mania. A substantial minority of clinically referred children shows unstable or steadily increasing manic symptoms, and these patterns have distinct clinical correlates.

Mycobacterium tuberculosis arabinogalactan (AG) is an essential cell wall component. It provides a molecular framework serving to connect peptidoglycan to the outer mycolic acid layer. The biosynthesis of the arabinan domains of AG and lipoarabinomannan (LAM) occurs via a combination of membrane bound arabinofuranosyltransferases, all of which utilize decaprenol-1-monophosphorabinose as a substrate. The source of arabinose ultimately destined for deposition into cell wall AG or LAM originates exclusively from phosphoribosyl-1-pyrophosphate (pRpp), a central metabolite which is also required for other essential metabolic processes, such as de novo purine and pyrimidine biosyntheses. In M. tuberculosis, a single pRpp synthetase enzyme (Mt-PrsA) is solely responsible for the generation of pRpp, by catalyzing the transfer of pyrophosphate from ATP to the C1 hydroxyl position of ribose-5-phosphate. Here, we report a detailed biochemical and biophysical study of Mt-PrsA, which exhibits the most rapid enzyme kinetics reported for a pRpp synthetase.

We investigated the relation between cell wall structure and the resulting mechanical characteristics of different plant tissues. Special attention was paid to the mechanical behaviour beyond the linear-elastic range, the underlying micromechanical processes and the fracture characteristics. The previously proposed model of reorientation and slippage of the cellulose microfibrils in the cell wall [H.-CH. Spatz et al. (1999) J Exp Biol 202:3269-3272) was supported and is here refined, using measurements of the changes in microfibrillar angle during straining. Our model explains the widespread phenomenon of stress-strain curves with two linear portions of different slope and sheds light on the micromechanical processes involved in viscoelasticity and plastic yield. We also analysed the velocity dependence of viscoelasticity under the perspective of the Kelvin model, resolving the measured viscoelasticity into functions of a velocity-dependent and a velocity-independent friction. The influence of lignin on the above-mentioned mechanical properties was examined by chemical lignin extraction from tissues of Aristolochia macrophylla Lam. and by the use of transgenic plants of Arabidopsis thaliana (L.) Heynh. with reduced lignin content. Additionally, the influence of extraction of hemicelluloses on the mechanical properties was investigated as well as a cell wall mutant of Arabidopsis with an altered configuration of the cellulose microfibrils.

The recently described single-nucleotide polymorphism CT60, located in the 3'-untranslated region of the CTLA4 (cytotoxic T-lymphocyte antigen 4 ) gene, has been associated with susceptibility to several autoimmune diseases and has also been shown to be involved in immune responses following allogeneic stem cell transplantation (SCT). However, the contribution of the CTLA4 genotype to the control of minimal residual disease in patients with acute myeloid leukemia (AML) has yet to be explored. We investigated the association between the CTLA4 CT60 A/G genotype and the incidence of leukemic relapse in 143 adult patients with AML in first complete remission after the same chemotherapy protocol (CETLAM LAM'03). The CT60 AA genotype was associated with a higher rate of leukemic relapse (56.4 vs 35.6%, P=0.004; hazard ratio (HR)=2.64, 95% confidence interval (CI)=1.36-5.14) and lower overall survival at 3 years (39.4 vs 68.4%, P=0.004; HR=2.80, 95% CI=1.39-5.64). This is the first study to report an association between polymorphisms at CTLA-4 and AML relapse.

In this study, we describe the development and evaluation of a novel multiple-antigen ELISA for rapid diagnosis and screening of active tuberculosis (TB). The humoral immune responses of 136 active TB patients and 57 healthy subjects against antigens Rv3425, 38kDa and lipoarabinomannan (LAM) from Mycobacterium tuberculosis H37Rv were examined by ELISA. Three essential results were obtained. (i) Rv3425 antigen is a potential candidate for serodiagnosis of active TB. Of 136 active TB patients, Rv3425 antigen provided a sensitivity of 31.6%, lower than that of LAM antigen, but higher than that of 38kDa antigen, with an overall specificity of 100%. (ii) For 62 smear-negative pulmonary TB patients and 15 extra-pulmonary TB patients, the multiple-antigen test provided a sensitivity of 43.5% and 26.7%, respectively, representing an improvement over acid-fast bacilli (AFB) smear-based diagnosis. (iii) Compared with the single-antigen ELISA and the two available commercial kits, the multiple-antigen test offered the highest accuracy (71.0%). In conclusion, the multiple-antigen ELSIA test based on Rv3425, 38kDa, and LAM antigens is a potentially useful tool for the serodiagnosis and screening of active TB. Combinations of Rv3425 with other mycobacterial antigens may also be worthy of further investigation.

Mutations in tuberous sclerosis complex (TSC) genes are associated with dysregulated mammalian target of rapamycin (mTOR)/Akt signaling and unusual neoplasms called perivascular epithelioid cell tumors (PEComas), including angiomyolipomas (AMLs) and lymphangioleiomyomatosis (LAM). Tools that quantify metabolic activity and total body burden of AML and LAM cells would be valuable for the assessment of disease progression and the response to therapy in patients with TSC and LAM. Our hypothesis was that constitutive activation of mTOR in LAM and AML cells would result in increased glucose uptake of [(18)F]2-fluoro-2-deoxyglucose (FDG) on PET scanning, as has been suggested by a single prior case report. After institutional review board approval, FDG-PET scanning was performed in six LAM patients. Six additional LAM patients underwent FDG-PET scanning for clinical evaluation of suspected malignancy. Pleural uptake related to prior therapy was identified in four individuals with a remote history of talc pleurodesis. Focal increased uptake was observed in a supraclavicular lymph node in a patient with Hodgkin lymphoma and in a lung nodule in a patient with a biopsy-documented primary lung adenocarcinoma. In one TSC-LAM patient with a biopsy-documented malignant uterine PEComa, robust uptake was noted in metastatic nodules in the lung but not in the LAM-involved lung parenchyma or the patient's massive abdominal lymphangioleiomyomas. No abnormal uptake was identified in the AMLs or LAM lesions in any patients. This pilot study suggests that FDG-PET scans are negative in patients with benign PEComas and therefore are not likely to be useful for estimating the burden of disease in patients with TSC or LAM, but that FDG-PET scans can be used to identify or exclude other neoplasms in these patients.

We have previously developed a diagnostic test for tuberculosis based on detection of mycobacterial lipoarabinomannan (LAM) in urine. The method depended on a laborious concentration step. We have now developed an easy to perform test based on a magnetic immunoassay platform, utilizing high avidity monoclonal antibodies for the detection of LAM in urine. With this method the analytical sensitivity of the assay was increased 50-100-fold compared to conventional ELISA. In a pilot study of HIV-negative patients with microbiologically verified TB (n=17) and healthy controls (n=22) the sensitivity of the test was 82% and the specificity 100%. This is in stark positive contrast to a range of studies using available commercial tests with polyclonal anti-LAM Abs where the sensitivity of the tests in HIV-negative TB patients was very low.

OBJECTIVE

EUS-guided choledochoduodenostomy (EUS-CDS) using conventional tubular stents has been successfully performed. However, EUS-CDS carries a high risk of bile leakage with attendant adverse events. This study aimed to prospectively evaluate the long-term outcome of EUS-CDS using a dedicated lumen-apposing metal stent (LAMS).

METHODS

Nineteen patients (mean age, 70.6 years; 12 men) with unresectable malignant diseases were treated in 5 tertiary referral centers. EUS-CDS was performed using a fully covered LAMS with a cautery-enhanced delivery system for EUS-CDS.

RESULTS

All stents were successfully deployed without any adverse events. Jaundice improved in 79% of the patients within 7 days and finally in 95%. In 95% of patients the stents remained in good anastomotic position without migration or dislocation during the follow-up period (median, 184 days; range, 12-819). One patient had a fever the day after stent placement. During the follow-up period 5 patients had secondary stent obstruction because of food residue (n = 2), kinking (n = 1), suspected tumor ingrowth (n = 1), and spontaneous dislodgement (n = 1). Five patients developed obstruction in the second portion of the duodenum. The overall adverse event rate was 36.8% (7/19), mostly with mild severity.

CONCLUSIONS

This study revealed that the novel dedicated LAMS used has high technical and clinical success rates for EUS-CDS. The adverse events and patency rates are inferior to the historically reported data of a conventional transpapillary metal stent. Development of a more suitable dedicated LAMS is anticipated.

Medicinal plants constitute an important source of potential therapeutic agents for diabetes. In the present study, we investigated the effects of Moringa oleifera (MO) Lam, Moringacea, on glucose tolerance in Wistar rats and Goto-Kakizaki (GK) rats, modeled type 2 diabetes. Major polyphenols in MO powder were quercetin glucosides, rutin, kaempferol glycosides and chlorogenic acids by HPLC analysis. As the results of glucose tolerance test, MO significantly decreased the blood glucose at 20, 30, 45and 60 min for GK rats and at 10, 30 and 45 min for Wistar rats (p<0.05) compared to the both controls after glucose administration. The area under the curve of changes in the blood glucose was significantly higher in the GK control group than in the GK plus MO group (p<0.05) in the periods 30-60 min and 60-120 min. Furthermore, MO significantly decreased stomach emptying in GK rats (p<0.05). The results indicated that MO has an ameliorating effect for glucose intolerance, and the effect might be mediated by quercetin-3-glucoside and fiber contents in MO leaf powder. The action of MO was greater in GK rats than in Wistar rats.

BACKGROUND

Little is known of the morphology of the pneumocytes lining the parenchymal cysts in lymphangioleiomyomatosis (LAM).

OBJECTIVE

To evaluate the structural characteristics of the alveolar epithelial cells in LAM.

METHODS

Immunohistochemical and electron microscopic studies were performed on lung tissue from 22 women with pulmonary LAM.

RESULTS

Epithelial cells that reacted with PE-10 (a mouse monoclonal antibody that recognizes the surfactant apoprotein A in type II pneumocytes) and TTF-1 (an antibody that identifies nuclear transcription factor found in type II pneumocytes) were the predominant cell type lining the surfaces of lesions of LAM and normal areas of lung. Scanning and transmission electron microscopic studies confirmed that these cells were type II pneumocytes as demonstrated by (1) apical microvilli, (2) electron-dense lamellar bodies, and (3) cytoplasmic projections that extended from the basal surfaces into the underlying connective tissue, where they made extensive contact with interstitial connective tissue cells. A few cells had morphologic characteristics of type I pneumocytes, including large flat surfaces lacking microvilli. Cells that appeared intermediate between type I and type II pneumocytes were observed occasionally.

CONCLUSIONS

These observations and the reactivity of these cells with antibody to proliferating cell nuclear antigen demonstrate that extensive hyperplasia of type II pneumocytes is a major characteristic of LAM.

Longan (Dimocarpus longan Lour, syn. Euphoria longan Lam.) represents an important fruit in Northern Thailand and has significant economic impact. The fruit is either consumed fresh or as commercially prepared dried and canned products. The canning industry in Thailand produces considerable quantities of waste products, in particular Longan seeds. Because these seeds may be an exploitable source of natural phenolic antioxidants, it was of interest to identify, purify and quantitate the major potential antioxidant phenolics contained therein. The polyphenolic fraction from ground Longan seeds was obtained by extraction with methanol after delipidation with hexane. The hexane extract contained predominantly long-chain fatty acids with major contributions from palmitic (35%) and oleic (28%) acids. The polyphenolic fraction (80.90 g/kg dry weight) was dominated by ellagic acid (25.84 g/kg) and the known ellagitannins corilagin (13.31 g/kg), chebulagic acid (13.06 g/kg), ellagic acid 4-O-α-l-arabinofuranoside (9.93 g/kg), isomallotinic acid (8.56 g/kg) and geraniin (5.79 g/kg). Structure elucidation was performed with mass spectrometry and complete assignment of (1)H and (13)C NMR signals. The methanol extracts exhibited strong antioxidant capacities with an IC(50) of 154 μg/ml for reactive oxygen species attack on salicylic acid and 78 μg/ml for inhibition of xanthine oxidase in the hypoxanthine/xanthine oxidase assay. The extracts were less effective in the 2-deoxyguanosine assay (IC(50)=2.46 mg/ml), indicating that gallates along with ellagic acid and its congeners exert their potential antioxidant effects predominantly by precipitation of proteins such as xanthine oxidase. This was confirmed for the pure compounds gallic acid, methyl gallate, ellagic acid and corilagin.

The evolution of lung transplantation has offered an additional treatment option for patients with a variety of end-stage lung diseases, including some with systemic disorders. Lymphangiomyomatosis (LAM) is a multisystem disease of premenopausal women. The lung is the most frequently involved vital organ, and respiratory failure is the most common case of death. A small number of patients with LAM have undergone lung transplantation. This report describes a case of recurrent LAM in the allograft after single lung transplantation and discusses the implications of this finding.

We sought to identify biologic indicators of prognosis in a series of 94 follicular lymphoma (FL) patients, focusing on markers of the host immune response as well as of B-cell maturation. Immune response was assessed with immunostains for CD68 (for lymphoma-associated macrophages, LAMs) and FOXP3 (regulatory T-cells). Lymphoma cells were evaluated for expression of bcl-2, CD10, and MUM-1. Clinical data were obtained for FLIPI, presence of bulky disease, presence of B-symptoms, treatment, and overall survival (OS). For the 69 initially treated patients, extrafollicular CD68+ cells (ef-CD68) and follicular FOXP3+ cells (f-FOXP3) were associated with shorter OS, while receipt of rituximab was associated with longer OS. Multivariable analysis showed ef-CD68 was the only independent factor associated with shorter OS. In subset analysis, ef-CD68 remained statistically significant in rituximab-naïve but not rituximab-treated patients. We confirm the importance of LAMs and f-FOXP3 as predictors of OS in FL.

Lymphangioleiomyomatosis (LAM), characterized by alveolar smooth muscle proliferation and cystic destruction of lung parenchyma, can occur as a rare sporadic disease or as a complication of tuberous sclerosis (TSC). It is a cystic lung disease, usually generalized and progressive, may be extremely difficult to treat and has been considered to have a poor prognosis. It has almost exclusively been reported to present in women of childbearing age, most commonly with dyspnoea and pneumothorax. We reviewed the English literature from 1939 to 1997 for cases of LAM both with and without TSC, in order to document the prevalence, clinical features, investigations, treatment and outcome within and between these two groups. No study has yet determined the prevalence of LAM symptomatically within the general population, but it probably affects 1-3% of the TSC population. Patients with TSC often present with an insidious onset of dyspnoea whilst non-TSC patients present more commonly with acute breathlessness secondary to pneumothorax. Patients with TSC are also less likely to suffer from chylothorax. The age of onset of symptoms and of diagnosis are similar. LAM is rare in children and even less common in males in both groups. The natural course of LAM remains unclear and effect of treatment variable. Although symptomatic LAM is uncommon it causes a significant amount of morbidity and mortality both in the TSC and general population, but asymptomatic LAM is not uncommon in TSC. Further research is required to determine the natural history of this condition and to evaluate current treatment regimes.

BACKGROUND

Currently, there is no consensus on the efficacy and resistance of de novo combination therapy versus monotherapy for treatment naive patients of chronic hepatitis B (CHB).

OBJECTIVE

The aim of this study was to evaluate the effectiveness and resistance of de novo combination of lamivudine (LAM) and adefovir dipivoxil (ADV) compared with entecavir (ETV) monotherapy for nucleos(t)ide-naive patients with CHB.

METHODS

Publications on the effectiveness and resistance of LAM plus ADV versus ETV monotherapy for nucleos(t)ide-naive patients with CHB were identified by a search of PubMed, Embase, the Cochrane Library, Web of science, OVID, and CBM (Chinese Biological Medical Literature) until May 1, 2013. Biochemical response, hepatitis B e antigen seroconversion, and viroligic response were extracted and combined to obtain an integrated result. Viral resistance and safety were reviewed.

RESULTS

Five eligible studies (328 patients in total) were included in the analysis. LAM plus ADV combination therapy produced more rapid HBV DNA reduction rate at 12 weeks than that of ETV monotherapy. At 48 weeks, the combination group had superior viroligic response rates compared with ETV group (90.0% vs. 78.9%, P=0.01). The difference in the ALT normalization and HBeAg seroconversion rates was not found. At week 96, LAM + ADV was more effective than ETV in ALT normalization [RR = 1. 11, 95% CI (1.02, 1.21), P =0.01] and HBeAg seroconversion [RR = 2.00, 95% CI (1.26, 3.18, P=0.003)], and no significant difference was found in the virologic response (P =0.23). No viral resistance occurred in combination therapy and six patients in ETV group were experienced with viral breakthrough. Both groups were well tolerated.

CONCLUSIONS

The de novo LAM plus ADV combination therapy for treatment-naïve patients with CHB was greater than ETV monotherapy in both biochemical response and HBeAg seroconversion rate up to 96 weeks. The rate of emergence of viral resistance in the combination group was less than that in the ETV monotherapy.

The use of lipoarabinomannan (LAM; obtained from Mycobacterium paratuberculosis) in and ELISA (LAM-ELISA) to test 75 sheep sera from a paratuberculosis-infected flock resulted in an approximate threefold increase in sensitivity (from 23.5% to 70.6%), compared with the use of Annau's polysaccharide in a complement fixation test (P-CFT). Even after manipulation of the LAM-ELISA cut-off value to produce a specificity of 100% to match that of the P-CFT, the sensitivity still was approximately twofold greater than that of the P-CFT. Anti-bovine monoclonal antiglobulin-enzyme conjugates matched commercially available anti-ovine polyclonal antiglobulin-enzyme conjugates with respect to sensitivity and specificity. False-positive results were found to be less frequent after combining 2 serodiagnostic tests, LAM-ELISA and D antigenagar gel immunodiffusion, resulting in an increase in specificity from 88.1% to 95.2%. The repeatability of true seropositive and seronegative results was found to be 89.5% and 91.1%, respectively, for sera obtained less than or equal to 1 month prior to slaughter and 91.7% and 95.5%, respectively, for reanalysis of sera obtained at the time of slaughter.

Life-history theory predicts evolutionary changes in reproductive traits and intrinsic mortality rates in response to differences in extrinsic mortality rates. Trade-offs between life- history traits play a pivotal role in these predictions, and such trade-offs are mediated, at least in part, by physiological allocations. To gain insight into these trade-offs, we have been performing a long-term experiment in which we allow fruitflies, Drosophila melanogaster, to evolve in response to high (HAM) and low (LAM) adult mortality rates. Here we analyze the physiological correlates of the life-history trade-offs. In addition to changing development time and early fecundity in the direction predicted, high adult mortality affected three traits expressed early in life-body size, growth rate, and ovariole number-but had little or no effect on body composition (relative fat content), viability, metabolic rate, activity, starvation resistance, or desiccation resistance. Correlations among lines revealed trade-offs between early fecundity, late fecundity, and starvation resistance, which appear to be mediated by differential allocation of lipids.

The emergence of multidrug-resistant tuberculosis (TB) and problems with the BCG tuberculosis vaccine to protect humans against TB have prompted investigations into alternative approaches to combat this disease by exploring novel bacterial drug targets and vaccines. Phosphatidylinositol mannosides (PIMs) are biologically important glycoconjugates and represent common essential precursors of more complex mycobacterial cell wall glycolipids including lipomannan (LM), lipoarabinomannan (LAM), and mannan capped lipoarabinomannan (ManLAM). Synthetic PIMs constitute important biochemical tools to elucidate the biosynthesis of this class of molecules, to reveal PIM interactions with host cells, and to investigate the function of PIMs as potential antigens and/or adjuvants for vaccine development. Here, we report the efficient synthesis of all PIMs including phosphatidylinositol (PI) and phosphatidylinositol mono- to hexa-mannoside (PIM1 to PIM6). Robust synthetic protocols were developed for utilizing bicyclic and tricyclic orthoesters as well as mannosyl phosphates as glycosylating agents. Each synthetic PIM was equipped with a thiol-linker for immobilization on surfaces and carrier proteins for biological and immunological studies. The synthetic PIMs were immobilized on microarray slides to elucidate differences in binding to the dendritic cell specific intercellular adhesion molecule-grabbing nonintegrin (DC-SIGN) receptor. Synthetic PIMs served as immune stimulators during immunization experiments in C57BL/6 mice when coupled to the model antigen keyhole-limpet hemocyanin (KLH).

The resistance mechanism of a glyphosate-resistant Lolium multiflorum Lam. biotype collected in Córdoba (Southern Spain) was examined. Resistance Factor values at three different growth stages ranged between 4.77 and 4.91. At 96 hours after treatment (HAT) the S biotype had accumulated seven times more shikimic acid than the R biotype. There were significant differences in translocation of (14)C-glyphosate between biotypes, i.e. at 96 HAT, the R biotype accumulated in the treated leaf more than 70% of the absorbed herbicide, in comparison with 59.21% of the S biotype; the R biotype translocated only 14.79% of the absorbed (14)C-glyphosate to roots, while in the S population this value was 24.79%. Visualization of (14)C-glyphosate by phosphor imaging showed a reduced distribution in the R biotype compared with the S. Glyphosate metabolism was not involved in the resistance mechanism due to both biotypes showing similar values of glyphosate at 96 HAT. Comparison of the EPSPS gene sequences between biotypes indicated that the R biotype has a proline 182 to serine amino acid substitution. In short, the resistance mechanism of the L. multiflorum Lam. biotype is due to an impaired translocation of the herbicide and an altered target site.

In order to investigate the molecular basis of the differences observed in the immunogenicity of various BCG vaccines, which may play a major role in BCG vaccination efficiency, the presence and the partial structure of the lipoarabinomannans (LAMs) were investigated in four different BCG strains (Pasteur, Glaxo, Copenhagen, and Japanese strains). According to their cell-wall extraction mode, the LAMs were subdivided into two classes, namely, parietal LAMs and cellular LAMs. From a structural point of view, the cellular LAMs and parietal LAMs both belong to the ManLAM class since the relevant structural features, described for ManLAMs, that is, the phosphatidyl-myo-Ins anchor and the manno-oligosaccharide caps were characterized. In addition, thanks to NMR experiments realized on the native ManLAMs, we prove the existence of succinyl groups and we determine their location on the C-2 of the 3,5-di-O-alpha-D-Araf units. The average number of succinyl groups was estimated at one and four per ManLAMs molecule for Glaxo and Japanese vaccines, respectively, and two for Pasteur and Copenhagen strains.

Infection of animal cells by vesicular stomatitis virus (VSV) results in inhibition of translation of cellular mRNA. We showed previously that, in BHK cells infected by the Glasgow isolate of VSV Indiana, this is due to competition during the initiation step of protein synthesis of viral and cellular mRNA for a constant, limiting number of ribosomes. We show here that infection of the same cells with the San Juan isolate of VSV resulted in a more rapid shutoff of host protein synthesis and that this was paralleled by a more rapid accumulation of viral mRNA. Extending our conclusion that shutoff is due to mRNA competition, we show further that the average size of polysomes translating viral and cellular mRNA was threefold smaller in cells infected by VSV San Juan than by VSV Glasgow, which, in turn, was about one-half that of uninfected cells. In all cases, cellular and viral mRNA's which encoded the same-sized polypeptides were found on the same-sized polysomes, a result indicating that the efficiency of translation of both types of mRNA's is about the same in the infected cell. Also, there was no preferential sequestration of viral or cellular mRNA's in ribonucleoprotein particles. Additional correlations between the levels of viral mRNA's and the inhibition of protein synthesis came from studies of three other wild-type VSV strains and also from studies with Vero and L cells. In particular, the rate of shutoff of L-cell protein synthesis after infection by any VSV isolate was slower than that in BHK cells, and this was correlated with a slower rate of accumulation of viral mRNA. VSV temperature-sensitive mutants which synthesized, at the nonper-missive temperature, no VSV mRNA failed to inhibit synthesis of cellular proteins. Stanners and co-workers (C. P. Stanners, A. M. Francoeur, and T. Lam, Cell 11:273-281, 1977) claimed that VSV mutant R1 inhibited synthesis of L cell protein synthesis less rapidly than did its parent wild-type strain HR. They concluded that this effect was due to a mutation in an unspecified VSV protein, "P." We found, in both L and BHK cells, that R1 infection resulted in a slightly slower inhibition of cellular mRNA translation than did HR infection and that this was correlated with a slightly reduced accumulation of VSV mRNA. The level of VSV mRNA, rather than any specific VSV protein, appeared to be the key factor in determining the rate of shutoff of host protein synthesis.

An observational study involving 304 dairy herds and three abattoirs was conducted between 1986 and 1989 to investigate the epidemiology of paratuberculosis in dairy cattle in Ontario. The objectives of this paper were to describe the method of data collection for the study, to present descriptive production statistics and to present estimates of the prevalence of paratuberculosis among dairy cattle in Ontario. Mycobacterium paratuberculosis was isolated from the distal ileum and/or the ileocecal lymph node of 5.5% of 400 cull cows. Based on a lipoarabinomannan antigen enzyme-linked immunosorbent assay (LAM-ELISA) on sera, the predicted true prevalence of paratuberculosis among 14,923 dairy cattle from 304 herds, was 6.1%. Nineteen percent of 2,943 fecal cultures were uninterpretable because of overgrowth with contaminating bacteria or fungi. It was concluded that the true prevalence of paratuberculosis among dairy cattle in Ontario was no greater, and may be less than the true prevalence among dairy cattle from various regions of the United States. However, at a practical level, for the purposes of trade policy, the present study suggests that the functional prevalence is very similar in the two countries.

The peroxidase content of sweet potato slices (Ipomoea batatas Lam.) increased nearly 100-fold following 84 hours incubation in an air atmosphere containing ethylene, 1 microliter per liter. The object of experiments reported here is to determine if this increase in peroxidase activity results from synthesis de novo of the enzyme or from activation of a preexisting inactive form of the enzyme.The enzymatic activity of each peroxidase isozyme increased during the incubation period, and each peroxidase isozyme appeared to incorporate (14)C-leucine. Polyacrylamide gel electrophoresis of the neutral peroxidase fraction showed that all peroxidase activity and essentially all radioactivity migrated as a single superimposable band. The other peroxidase fractions were less pure. Treatment of fresh slices, or slices collected midway in the time course with the inhibitor of protein synthesis, blasticidin S, (1 microgram per milliliter for one minute) caused an abrupt cessation of peroxidase formation and simultaneously an abrupt cessation of incorporation of (14)C-leucine into peroxidase isozymes. These observations indicate that the rapid increase in peroxidase activity in sweet potato slices results from synthesis de novo of the enzyme.

Development of an immunological tool to detect infection with Mycobacterium leprae would greatly benefit leprosy control programmes, as demonstrated by the contribution of the tuberculin test to tuberculosis control. In a new approach to develop a 'tuberculin-like' reagent for use in leprosy, two new fractions of M. leprae depleted of cross-reactive and immunomodulatory lipids- MLSA-LAM (cytosol-derived) and MLCwA (cell wall-derived)-have been produced in a form suitable for use as skin test reagents. T cell responses (interferon-gamma (IFN-gamma) and lymphoproliferation) to these two new fractions were evaluated in a leprosy-endemic area of Nepal using a simple in vitro whole blood test. The two fractions were shown to be highly potent T cell antigens in subjects exposed to M. leprae-paucibacillary leprosy patients and household contacts. Responses to the fractions decreased towards the lepromatous pole of leprosy. Endemic control subjects also showed high responses to the fractions, indicating high exposure to M. leprae, or cross-reactive mycobacterial antigens, in this Nepali population. The new fractions, depleted of lipids and lipoarabinomannan (LAM) gave enhanced responses compared with a standard M. leprae sonicate. The cell wall fraction appeared a more potent antigen than the cytosol fraction, which may be due to the predominance of the 65-kD GroEL antigen in the cell wall. The whole blood assay proved a robust field tool and a useful way of evaluating such reagents prior to clinical trials.