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"Greenstein, Robert"
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Is vaccination a viable method to control Johne’s disease caused by Mycobacterium avium subsp. paratuberculosis? Data from 12 million ovine vaccinations and 7.6 million carcass examinations in New South Wales, Australia from 1999–2009
by
Greenstein, Robert J.
,
Evers, Marilyn
,
Links, Ian J.
in
Abbreviations
,
Agricultural practices
,
Animal diseases
2021
Mycobacterium avium subsp. paratuberculosis (MAP) causes Johne's disease (or paratuberculosis), a chronic wasting disease of ruminants and other animals resulting from granulomatous enteritis. There are increasing concerns that MAP is zoonotic. The prevalence of Johne's disease is increasing worldwide. In an attempt to control an epidemic of ovine Johne's disease (OJD) in New South Wales (NSW), a government/industry sponsored voluntary vaccination/on-farm management program commenced in 2000. We report herein an observational study of changes in disease prevalence as vaccination progressed, based on abattoir surveillance data for OJD from 1999 to 2009. We also discuss the epidemiological, policy, regulatory, research, economic and sociological elements that contributed to the development of a mature control program, whose aim was to halt the epidemic spread of OJD in a naïve sheep population. NSW was divided into areas of \"High\" (HPA), \"Medium\" (MPA) and \"Low\" (LPA) OJD prevalence. A killed whole cell vaccine (Gudair®) was administered to sheep from 2000 to 2009. Trained examiners evaluated the viscera of adult sheep carcasses at slaughter for gross evidence of OJD. MAP infection was confirmed by histopathology. We show a decrease in the prevalence of lesions attributable to OJD in NSW concomitant with initiation of voluntary vaccination, on-farm management plans, abattoir monitoring and feedback of animal prevalence data to sheep producers. We conclude that a target of [less than or equal to] 1% regional prevalence of OJD affected sheep at slaughter is achievable using these interventions.
Journal Article
Vitamins A & D Inhibit the Growth of Mycobacteria in Radiometric Culture
2012
The role of vitamins in the combat of disease is usually conceptualized as acting by modulating the immune response of an infected, eukaryotic host. We hypothesized that some vitamins may directly influence the growth of prokaryotes, particularly mycobacteria.
The effect of four fat-soluble vitamins was studied in radiometric Bactec® culture. The vitamins were A (including a precursor and three metabolites,) D, E and K. We evaluated eight strains of three mycobacterial species (four of M. avium subspecies paratuberculosis (MAP), two of M. avium and two of M. tb. complex).
Vitamins A and D cause dose-dependent inhibition of all three mycobacterial species studied. Vitamin A is consistently more inhibitory than vitamin D. The vitamin A precursor, β-carotene, is not inhibitory, whereas three vitamin A metabolites cause inhibition. Vitamin K has no effect. Vitamin E causes negligible inhibition in a single strain.
We show that vitamin A, its metabolites Retinyl acetate, Retinoic acid and 13-cis Retinoic acid and vitamin D directly inhibit mycobacterial growth in culture. These data are compatible with the hypothesis that complementing the immune response of multicellular organisms, vitamins A and D may have heretofore unproven, unrecognized, independent and probable synergistic, direct antimycobacterial inhibitory activity.
Journal Article
Is Crohn's disease caused by a mycobacterium? Comparisons with leprosy, tuberculosis, and Johne's disease
by
Greenstein, Robert J
in
Animals
,
Anti-Bacterial Agents - adverse effects
,
Anti-Bacterial Agents - therapeutic use
2003
Although Crohn's disease is considered to be autoimmune in origin, there is increasing evidence that it may have an infectious cause. The most plausible candidate is Mycobacterium avium subspecies paratuberculosis (MAP). Intriguingly, Koch's postulates may have been fulfilled for MAP and Crohn's disease, even though they still have not been met for Mycobacterium leprae and leprosy. In animals MAP causes Johne's disease, a chronic wasting intestinal diarrhoeal disease evocative of Crohn's disease. Johne's disease occurs in wild and domesticated animals, including dairy herds. Viable MAP is found in human and cow milk, and is not reliably killed by standard pasteurisation. MAP is ubiquitous in the environment including in potable water. Since cell-wall-deficient MAP usually cannot be identified by Ziehl-Neelsen staining, identification of MAP in human beings requires culture or detection of MAP DNA or RNA. If infectious in origin, Crohn's disease should be curable with appropriate antibiotics. Many studies that argue against a causative role for MAP in Crohn's disease have used antibiotics that are inactive against MAP. However, trials that include macrolide antibiotics indicate that a cure for Crohn's disease is possible. The necessary length of therapy remains to be determined. Mycobacterial diseases have protean clinical manifestations, as does Crohn's disease. The necessity of stratifying Crohn's disease into two clinical manifestations (perforating and non-perforating) when interpreting the results of antibiotic therapy is discussed. Rational studies to evaluate appropriate therapies to cure Crohn's disease are proposed.
Journal Article
A Mosaic Activating Mutation in AKT1 Associated with the Proteus Syndrome
by
Robey, Pamela G
,
Darling, Thomas N
,
Lindhurst, Marjorie J
in
1-Phosphatidylinositol 3-kinase
,
AKT protein
,
AKT1 protein
2011
The Proteus syndrome affects some tissues and not others and is thought to be caused by a somatic mutation. Investigators found that the mutation is caused by activation of AKT1, an enzyme that mediates glucose metabolism, cell proliferation, and apoptosis.
The Proteus syndrome is characterized by patchy or segmental overgrowth and hyperplasia of multiple tissues and organs, along with susceptibility to the development of tumors
1
,
2
(Figure 1). It is thought that Joseph Merrick, an Englishman who lived in the late 19th century and became the subject of the play and film
The Elephant Man,
had the Proteus syndrome.
This uncommon syndrome (with an incidence of <1 case per 1 million population) has not been reported to recur in a family but has been reported in discordant monozygotic twins.
3
These observations support the hypothesis that the Proteus syndrome is caused . . .
Journal Article
Clinical course of sly syndrome (mucopolysaccharidosis type VII)
2016
BackgroundMucopolysaccharidosis VII (MPS VII) is an ultra-rare disease characterised by the deficiency of β-glucuronidase (GUS). Patients’ phenotypes vary from severe forms with hydrops fetalis, skeletal dysplasia and mental retardation to milder forms with fewer manifestations and mild skeletal abnormalities. Accurate assessments on the frequency and clinical characteristics of the disease have been scarce. The aim of this study was to collect such data.MethodsWe have conducted a survey of physicians to document the medical history of patients with MPS VII. The survey included anonymous information on patient demographics, family history, mode of diagnosis, age of onset, signs and symptoms, severity, management, clinical features and natural progression of the disease.ResultsWe collected information on 56 patients from 11 countries. Patients with MPS VII were classified based on their phenotype into three different groups: (1) neonatal non-immune hydrops fetalis (NIHF) (n=10), (2) Infantile or adolescent form with history of hydrops fetalis (n=13) and (3) Infantile or adolescent form without known hydrops fetalis (n=33). Thirteen patients with MPS VII who had the infantile form with history of hydrops fetalis and survived childhood, had a wide range of clinical manifestations from mild to severe. Five patients underwent bone marrow transplantation and one patient underwent enzyme replacement therapy with recombinant human GUS.ConclusionsMPS VII is a pan-ethnic inherited lysosomal storage disease with considerable phenotypical heterogeneity. Most patients have short stature, skeletal dysplasia, hepatosplenomegaly, hernias, cardiac involvement, pulmonary insufficiency and cognitive impairment. In these respects it resembles MPS I and MPS II. In MPS VII, however, one unique and distinguishing clinical feature is the unexpectedly high proportion of patients (41%) that had a history of NIHF. Presence of NIHF does not, by itself, predict the eventual severity of the clinical course, if the patient survives infancy.
Journal Article
On the Action of Methotrexate and 6-Mercaptopurine on M. avium Subspecies paratuberculosis
by
Greenstein, Robert J.
,
Brown, Sheldon T.
,
Su, Liya
in
6-Mercaptopurine
,
Ampicillin
,
Ampicillin - pharmacology
2007
Clinical improvement in inflammatory bowel disease (IBD) treated with methotrexate and 6-mercaptopurine (6-MP) is associated with a decrease in pro-inflammatory cytokines. This has been presumed to indicate the mechanism of action of methotrexate and 6-MP. Although controversial, there are increasingly compelling data that Mycobacterium avium subspecies paratuberculosis (MAP) may be an etiological agent in some or all of IBD. We hypothesized that the clinical efficacy of methotrexate and 6-MP in IBD may be to simply inhibit the growth of MAP.
The effect on MAP growth kinetics by methotrexate and 6-MP were evaluated in cell culture of two strains each of MAP and M. avium using a radiometric ((14)CO(2) BACTEC detection system that quantifies mycobacterial growth as arbitrary \"growth index units\" (GI). Efficacy data are presented as \"percent decrease in cumulative GI\" (% -DeltacGI).
The positive control antibiotic (clarithromycin) has >or=85% -DeltacGI at a concentration of 0.5 microg/ml. The negative control (ampicillin) has minimal inhibition at 64 microg/ml. MAP ATCC 19698 shows >or=80% -DeltacGI for both agents by 4 microg/ml. With the other three isolates, although more effective than ampicillin, 6-MP is consistently less effective than methotrexate.
We show that methotrexate and 6-MP inhibit MAP growth in vitro. Each of the four isolates manifests different % -DeltacGI. These data are compatible with the hypothesis that the clinical improvement in patients with IBD treated with methotrexate and 6-MP could be due to treating a MAP infection. The decrease in pro-inflammatory cytokines, thought to be the primary mechanism of action, may simply be a normal, secondary, physiological response. We conclude that henceforth, in clinical studies that evaluate the effect of anti-MAP agents in IBD, the use of methotrexate and 6-MP should be excluded from any control groups.
Journal Article
On the Action of 5-Amino-Salicylic Acid and Sulfapyridine on M. avium including Subspecies paratuberculosis
by
Greenstein, Robert J.
,
Brown, Sheldon T.
,
Su, Liya
in
Acids
,
Animals
,
Anti-Infective Agents - pharmacology
2007
Introduced in 1942, sulfasalazine (a conjugate of 5-aminosalicylic acid (5-ASA) and sulfapyridine) is the most prescribed medication used to treat \"inflammatory\" bowel disease (IBD.) Although controversial, there are increasingly compelling data that Mycobacterium avium subspecies paratuberculosis (MAP) may be an etiological agent in some or all of IBD. We have shown that two other agents used in the therapy of IBD (methotrexate and 6-MP) profoundly inhibit MAP growth. We concluded that their most plausible mechanism of action is as antiMAP antibiotics. We herein hypothesize that the mechanism of action of 5-ASA and/or sulfapyridine may also simply be to inhibit MAP growth.
The effect on MAP growth kinetics by sulfasalazine and its components were evaluated in bacterial culture of two strains each of MAP and M. avium, using a radiometric ((14)CO(2) BACTEC(R)) detection system that quantifies mycobacterial growth as arbitrary \"growth index units\" (GI). Efficacy data are presented as \"percent decrease in cumulative GI\" (%-DeltacGI).
There are disparate responses to 5-ASA and sulfapyridine in the two subspecies. Against MAP, 5-ASA is inhibitory in a dose-dependent manner (MAP ATCC 19698 46%-DeltacGI at 64 microg/ml), whereas sulfapyridine has virtually no effect. In contrast, against M. avium ATCC 25291, 5-ASA has no effect, whereas sulfapyridine (88%-DeltacGI at 4 microg/ml) is as effective as methotrexate, our positive control (88%-DeltacGI at 4 microg/ml).
5-ASA inhibits MAP growth in culture. We posit that, unknowingly, the medical profession has been treating MAP infections since sulfasalazine's introduction in 1942. These observations may explain, in part, why MAP has not previously been identified as a human pathogen. We conclude that henceforth in clinical trials evaluating antiMAP agents in IBD, if considered ethical, the use of 5-ASA (as well as methotrexate and 6-MP) should be excluded from control groups.
Journal Article
Recommendations for Reporting Weight Loss
by
Greenstein, Robert J.
,
Deitel, Mervyn
in
Body Mass Index
,
Humans
,
Periodicals as Topic - standards
2003
Journal Article
Crohn’s disease: failure of a proprietary fluorescent in situ hybridization assay to detect M. avium subspecies paratuberculosis in archived frozen intestine from patients with Crohn’s disease
by
Endres, Paul
,
Greenstein, Robert J.
,
Brown, Sheldon T.
in
Actin
,
Bacterial infections
,
Biomedical and Life Sciences
2020
Objectives
Although controversial, there is increasing concern that Crohn’s disease may be a zoonotic infectious disease consequent to a mycobacterial infection. The most plausible candidate is
M. avium
subspecies
paratuberculosis
(MAP) that is unequivocally responsible for Johne’s disease in ruminants. The purpose of this study was to evaluate a proprietary (Affymetrix™ RNA view
®
) fluorescent in situ hybridization (FISH) assay for MAP RNA. Non-identifiable intestine from patients with documented Crohn’s disease was assayed according to the manufacturer’s instructions and with suggested modifications. Probes were custom designed for MAP and human β-actin (as the eukaryotic housekeeping gene) from published genomes.
Results
Repetitively, false positive signal was observed in our “No-Probe” negative control. Attempts were made to correct this according to the manufacturer’s suggestions (by modifying wash solutions, using recommended hydrochloric acid titration and different fluorescent filters). None prevented false positive signal in the “No-Probe” control. It is concluded that when performed according to manufactures instruction and with multiple variations on the manufactures recommended suggestions to correct for false positive signal, that the Affymetrix™ RNA view
®
cannot be used to detect MAP in pre-frozen resected intestine of humans with Crohn’s disease.
Journal Article
On the Action of Cyclosporine A, Rapamycin and Tacrolimus on M. avium Including Subspecies paratuberculosis
by
Greenstein, Robert J.
,
Brown, Sheldon T.
,
Juste, Ramon A.
in
Antibiotics
,
Antigens
,
Azathioprine
2008
Mycobacterium avium subspecies paratuberculosis (MAP) may be zoonotic. Recently the \"immuno-modulators\" methotrexate, azathioprine and 6-MP and the \"anti-inflammatory\" 5-ASA have been shown to inhibit MAP growth in vitro. We concluded that their most plausible mechanism of action is as antiMAP antibiotics. The \"immunosuppressants\" Cyclosporine A, Rapamycin and Tacrolimus (FK 506) treat a variety of \"autoimmune\" and \"inflammatory\" diseases. Rapamycin and Tacrolimus are macrolides. We hypothesized that their mode of action may simply be to inhibit MAP growth.
The effect on radiometric MAP (14)CO(2) growth kinetics of Cyclosporine A, Rapamycin and Tacrolimus on MAP cultured from humans (Dominic & UCF 4) or ruminants (ATCC 19698 & 303) and M. avium subspecies avium (ATCC 25291 & 101) are presented as \"percent decrease in cumulative GI\" (%-DeltacGI.)
The positive control clofazimine has 99%-DeltacGI at 0.5 microg/ml (Dominic). Phthalimide, a negative control has no dose dependent inhibition on any strain. Against MAP there is dose dependent inhibition by the immunosuppressants. Cyclosporine has 97%-DeltacGI by 32 microg/ml (Dominic), Rapamycin has 74%-DeltacGI by 64 microg/ml (UCF 4) and Tacrolimus 43%-DeltacGI by 64 microg/ml (UCF 4)
We show heretofore-undescribed inhibition of MAP growth in vitro by \"immunosuppressants;\" the cyclic undecapeptide Cyclosporine A, and the macrolides Rapamycin and Tacrolimus. These data are compatible with our thesis that, unknowingly, the medical profession has been treating MAP infections since 1942 when 5-ASA and subsequently azathioprine, 6-MP and methotrexate were introduced in the therapy of some \"autoimmune\" and \"inflammatory\" diseases.
Journal Article