The development of Assessment of SpondyloArthritis international Society classification criteria for axial spondyloarthritis (part II): validation and final selection

OBJECTIVE

To validate and refine two sets of candidate criteria for the classification/diagnosis of axial spondyloarthritis (SpA).

METHODS

All Assessment of SpondyloArthritis international Society (ASAS) members were invited to include consecutively new patients with chronic (> or =3 months) back pain of unknown origin that began before 45 years of age. The candidate criteria were first tested in the entire cohort of 649 patients from 25 centres, and then refined in a random selection of 40% of cases and thereafter validated in the remaining 60%.

RESULTS

Upon diagnostic work-up, axial SpA was diagnosed in 60.2% of the cohort. Of these, 70% did not fulfil modified New York criteria and, therefore, were classified as having "non-radiographic" axial SpA. Refinement of the candidate criteria resulted in new ASAS classification criteria that are defined as: the presence of sacroiliitis by radiography or by magnetic resonance imaging (MRI) plus at least one SpA feature ("imaging arm") or the presence of HLA-B27 plus at least two SpA features ("clinical arm"). The sensitivity and specificity of the entire set of the new criteria were 82.9% and 84.4%, and for the imaging arm alone 66.2% and 97.3%, respectively. The specificity of the new criteria was much better than that of the European Spondylarthropathy Study Group criteria modified for MRI (sensitivity 85.1%, specificity 65.1%) and slightly better than that of the modified Amor criteria (sensitivity 82.9, specificity 77.5%).

CONCLUSION

The new ASAS classification criteria for axial SpA can reliably classify patients for clinical studies and may help rheumatologists in clinical practice in diagnosing axial SpA in those with chronic back pain.

TRIAL REGISTRATION NUMBER

NCT00328068.

Full-genome RNAi profiling of early embryogenesis in Caenorhabditis elegans

A key challenge of functional genomics today is to generate well-annotated data sets that can be interpreted across different platforms and technologies. Large-scale functional genomics data often fail to connect to standard experimental approaches of gene characterization in individual laboratories. Furthermore, a lack of universal annotation standards for phenotypic data sets makes it difficult to compare different screening approaches. Here we address this problem in a screen designed to identify all genes required for the first two rounds of cell division in the Caenorhabditis elegans embryo. We used RNA-mediated interference to target 98% of all genes predicted in the C. elegans genome in combination with differential interference contrast time-lapse microscopy. Through systematic annotation of the resulting movies, we developed a phenotypic profiling system, which shows high correlation with cellular processes and biochemical pathways, thus enabling us to predict new functions for previously uncharacterized genes.

The development of Assessment of SpondyloArthritis international Society classification criteria for axial spondyloarthritis (part I): classification of paper patients by expert opinion including uncertainty appraisal

OBJECTIVE

Non-radiographic axial spondyloarthritis (SpA) is characterised by a lack of definitive radiographic sacroiliitis and is considered an early stage of ankylosing spondylitis. The objective of this study was to develop candidate classification criteria for axial SpA that include patients with but also without radiographic sacroiliitis.

METHODS

Seventy-one patients with possible axial SpA, most of whom were lacking definite radiographic sacroiliitis, were reviewed as "paper patients" by 20 experts from the Assessment of SpondyloArthritis international Society (ASAS). Unequivocally classifiable patients were identified based on the aggregate expert opinion in conjunction with the expert-reported level of certainty of their judgement. Draft criteria for axial SpA were formulated and tested using classifiable patients.

RESULTS

Active sacroiliitis on magnetic resonance imaging (MRI) (odds ratio 45, 95% CI 5.3 to 383; p<0.001) was strongly associated with the classification of axial SpA. The knowledge of MRI findings led to a change in the classification of 21.1% of patients. According to the first set of candidate criteria (sensitivity 97.1%; specificity 94.7%) a patient with chronic back pain is classified as axial SpA in the presence of sacroiliitis by MRI or x rays in conjunction with one SpA feature or, if sacroilitiis is absent, in the presence of at least three SpA features. In a second set of candidate criteria, inflammatory back pain is obligatory in the clinical arm (sensitivity 86.1%; specificity 94.7%).

CONCLUSION

The ASAS group has developed candidate criteria for the classification of axial SpA that include patients without radiographic sacroiliitis. The candidate criteria need to be validated in an independent international study.

Normalized left ventricular systolic and diastolic function by steady state free precession cardiovascular magnetic resonance

We used state of the art CMR to define ranges for normal left ventricular volumes and systolic/diastolic function normalized to the influence of gender, body surface area and age. New CMR normalized ranges were modeled and displayed in graphical form for clinical use, with normalization for body surface area, gender, and age. The determination of normality, or the severity of abnormality, depends on the use of the appropriate reference ranges normalized to all 3 variables. These novel data have particular importance for clinical practice and clinical trials using CMR.

2010 update of the ASAS/EULAR recommendations for the management of ankylosing spondylitis

This first update of the ASAS/EULAR recommendations on the management of ankylosing spondylitis (AS) is based on the original paper, a systematic review of existing recommendations and the literature since 2005 and the discussion and agreement among 21 international experts, 2 patients and 2 physiotherapists in a meeting in February 2010. Each original bullet point was discussed in detail and reworded if necessary. Decisions on new recommendations were made - if necessary after voting. The strength of the recommendations (SOR) was scored on an 11-point numerical rating scale after the meeting by email. These recommendations apply to patients of all ages that fulfill the modified NY criteria for AS, independent of extra-articular manifestations, and they take into account all drug and non-drug interventions related to AS. Four overarching principles were introduced, implying that one bullet has been moved to this section. There are now 11 bullet points including 2 new ones, one related to extra-articular manifestations and one to changes in the disease course. With a mean score of 9.1 (range 8-10) the SOR was generally very good.

Effect of brain edema on infarct volume in a focal cerebral ischemia model in rats

BACKGROUND AND PURPOSE

Infarct volume is one of the common indexes for assessing the extent of ischemic brain injury following focal cerebral ischemia. Accuracy in the measurement of infarct volume is compounded by postischemic brain edema that may increase brain volume in the infarcted region. We evaluated the effect of brain edema on infarct volume determined by triphenyltetrazolium chloride and hematoxylin and eosin stains in a focal cerebral ischemia model in rats.

METHODS

In a middle cerebral artery occlusion model in rats, infarction is confined to the cerebral cortex. The infarct was delineated by triphenyltetrazolium chloride stain and, in selected samples, by hematoxylin and eosin stain. We determined infarct size at different times after the ischemic insult (6 hours to 7 days) in relation to the evolution of brain edema by the direct measurement of infarct volume. Indirect measurement to reduce the effect of edema on infarct volume was also conducted in the same brain samples.

RESULTS

Direct measurement showed that infarct volume fluctuated with the evolution of brain edema (one-way analysis of variance, p < 0.0001). Infarct volume determined by indirect measurement was independent of the extent of brain edema and remained stable from 6 hours to 3 days after ischemia. There was a good correlation between triphenyltetrazolium chloride and hematoxylin and eosin stains in delineating infarct volume with both direct and indirect measurement.

CONCLUSION

Traditional direct measurement of infarct volume is associated with an overestimation of infarct volume during the development of brain edema in the first 3 days after ischemia. This artifact can be reduced with indirect measurement, which is based on noninfarcted cortex volume.

GADD45 induction of a G2/M cell cycle checkpoint

G1/S and G2/M cell cycle checkpoints maintain genomic stability in eukaryotes in response to genotoxic stress. We report here both genetic and functional evidence of a Gadd45-mediated G2/M checkpoint in human and murine cells. Increased expression of Gadd45 via microinjection of an expression vector into primary human fibroblasts arrests the cells at the G2/M boundary with a phenotype of MPM2 immunopositivity, 4n DNA content and, in 15% of the cells, centrosome separation. The Gadd45-mediated G2/M arrest depends on wild-type p53, because no arrest was observed either in p53-null Li-Fraumeni fibroblasts or in normal fibroblasts coexpressed with p53 mutants. Increased expression of cyclin B1 and Cdc25C inhibited the Gadd45-mediated G2/M arrest in human fibroblasts, indicating that the mechanism of Gadd45-mediated G2/M checkpoint is at least in part through modulation of the activity of the G2-specific kinase, cyclin B1/p34(cdc2). Genetic and physiological evidence of a Gadd45-mediated G2/M checkpoint was obtained by using GADD45-deficient human or murine cells. Human cells with endogenous Gadd45 expression reduced by antisense GADD45 expression have an impaired G2/M checkpoint after exposure to either ultraviolet radiation or methyl methanesulfonate but are still able to undergo G2 arrest after ionizing radiation. Lymphocytes from gadd45-knockout mice (gadd45 -/-) also retained a G2/M checkpoint initiated by ionizing radiation and failed to arrest at G2/M after exposure to ultraviolet radiation. Therefore, the mammalian genome is protected by a multiplicity of G2/M checkpoints in response to specific types of DNA damage.

Survival in beta-thalassaemia major in the UK: data from the UK Thalassaemia Register

About 50% of UK patients with beta-thalassaemia major die before the age of 35 years, mainly because conventional iron-chelation therapy is too burdensome for full adherence. Patients require an individually-tailored treatment plan incorporating new, more tolerable approaches.

ASAS/EULAR recommendations for the management of ankylosing spondylitis

OBJECTIVE

To develop evidence based recommendations for the management of ankylosing spondylitis (AS) as a combined effort of the 'ASsessment in AS' international working group and the European League Against Rheumatism.

METHODS

Each of the 22 participants was asked to contribute up to 15 propositions describing key clinical aspects of AS management. A Delphi process was used to select 10 final propositions. A systematic literature search was then performed to obtain scientific evidence for each proposition. Outcome data for efficacy, adverse effects, and cost effectiveness were abstracted. The effect size, relative risk, number needed to treat, and incremental cost effectiveness ratio were calculated. On the basis of the search results, 10 major recommendations for the management of AS were constructed. The strength of recommendation was assessed based on the strength of the literature evidence, risk-benefit trade-off, and clinical expertise.

RESULTS

The final recommendations considered the use of non-steroidal anti-inflammatory drugs (NSAIDs) (conventional NSAIDs, coxibs, and co-prescription of gastroprotective agents), disease modifying antirheumatic drugs, treatments with biological agents, simple analgesics, local and systemic steroids, non-pharmacological treatment (including education, exercise, and physiotherapy), and surgical interventions. Three general recommendations were also included. Research evidence (categories I-IV) supported 11 interventions in the treatment of AS. Strength of recommendation varied, depending on the category of evidence and expert opinion.

CONCLUSION

Ten key recommendations for the treatment of AS were developed and assessed using a combination of research based evidence and expert consensus. Regular updating will be carried out to keep abreast of new developments in the management of AS.

How to diagnose axial spondyloarthritis early

BACKGROUND

Chronic low back pain (LBP), the leading symptom of ankylosing spondylitis (AS) and undifferentiated axial spondyloarthritis (SpA), precedes the development of radiographic sacroiliitis, sometimes by many years.

OBJECTIVE

To assign disease probabilities and to develop an algorithm to help in the early diagnosis of axial SpA.

METHODS

Axial SpA comprises AS and undifferentiated SpA with predominant axial involvement. Clinical features include inflammatory back pain (IBP), alternating buttock pain, enthesitis, arthritis, dactylitis, acute anterior uveitis, a positive family history, psoriasis, inflammatory bowel disease, and good response to NSAIDs. Associated laboratory findings include raised acute phase reactions, HLA-B27 association, and abnormalities on skeletal imaging. Sensitivities, specificities, and likelihood ratios (LRs) of these parameters were determined from published studies. A 5% prevalence of axial SpA among patients with chronic LBP was used. The probability of the presence of axial SpA, depending on the presence or absence of the above clinical features of SpA, was determined. A probability of > or = 90% was used to make a diagnosis of axial SpA.

RESULTS

The presence of inflammatory back pain features increased the probability of axial SpA from the background 5% prevalence to 14%. The presence of 2-3 SpA features was necessary to increase the probability of axial SpA to 90%. The highest LRs were obtained for HLA-B27 and MRI. Diagnostic algorithms to be used in daily practice were suggested.

CONCLUSIONS

This approach can help clinicians to diagnose with a high degree of confidence axial SpA at an early stage in patients with IBP who lack radiographic sacroiliitis.

Self-emulsifying drug delivery systems (SEDDS) of coenzyme Q10: formulation development and bioavailability assessment

The goals of our investigations are to develop and characterize self-emulsifying drug delivery systems (SEDDS) of coenzyme Q10 (CoQ10), using polyglycolyzed glycerides (PGG) as emulsifiers and to evaluate their bioavailability in dogs. Solubility of CoQ10 was determined in various oils and surfactants. SEDDS consisted of oil, a surfactant and a cosurfactant. Four types of self-emulsifying formulations were prepared using two oils (Myvacet 9-45 and Captex-200), two emulsifiers (Labrafac CM-10 and Labrasol) and a cosurfactant (lauroglycol). In all the formulations, the level of CoQ10 was fixed at 5.66% w/w of the vehicle. The in vitro self-emulsification properties and droplet size analysis of these formulations upon their addition to water under mild agitation conditions were studied. Pseudo-ternary phase diagrams were constructed identifying the efficient self-emulsification region. From these studies, an optimized formulation was selected and its bioavailability was compared with a powder formulation in dogs. Medium chain oils and Myvacet 9-45 provided higher solubility than long chain oils. Efficient and better self-emulsification processes were observed for the systems containing Labrafac CM-10 than formulations containing Labrasol. Addition of a cosurfactant improved the spontaneity of self-emulsification. From these studies, an optimized formulation consisting of Myvacet 9-45 (40%), Labrasol (50%) and lauroglycol (10%) was selected for its bioavailability assessment. A two-fold increase in the bioavailability was observed for the self-emulsifying system compared to a powder formulation. SEDDS have improved the bioavailability of CoQ10 significantly. The data suggest the potential use of SEDDS to provide an efficient way of improving oral absorption of lipophilic drugs.

New criteria for inflammatory back pain in patients with chronic back pain: a real patient exercise by experts from the Assessment of SpondyloArthritis international Society (ASAS)

OBJECTIVE

Inflammatory back pain (IBP) is an important clinical symptom in patients with axial spondyloarthritis (SpA), and relevant for classification and diagnosis. In the present report, a new approach for the development of IBP classification criteria is discussed.

METHODS

Rheumatologists (n = 13) who are experts in SpA took part in a 2-day international workshop to investigate 20 patients with back pain and possible SpA. Each expert documented the presence/absence of clinical parameters typical for IBP, and judged whether IBP was considered present or absent based on the received information. This expert judgement was used as the dependent variable in a logistic regression analysis in order to identify those individual IBP parameters that contributed best to a diagnosis of IBP. The new set of IBP criteria was validated in a separate cohort of patients (n = 648).

RESULTS

Five parameters best explained IBP according to the experts. These were: (1) improvement with exercise (odds ratio (OR) 23.1); (2) pain at night (OR 20.4); (3) insidious onset (OR 12.7); (4) age at onset <40 years (OR 9.9); and (5) no improvement with rest (OR 7.7). If at least four out of these five parameters were fulfilled, the criteria had a sensitivity of 77.0% and specificity of 91.7% in the patients participating in the workshop, and 79.6% and 72.4%, respectively, in the validation cohort.

CONCLUSION

This new approach with real patients defines a set of IBP definition criteria using overall expert judgement on IBP as the gold standard. The IBP experts' criteria are robust, easy to apply and have good face validity.

Reversible activation of c-Myc in skin: induction of a complex neoplastic phenotype by a single oncogenic lesion

The protooncogene c-myc regulates cell growth, differentiation, and apoptosis, and its aberrant expression is frequently observed in human cancer. However, the consequences of activating c-Myc in an adult tissue, in which these cellular processes are part of normal homeostasis, remain unknown. In order to achieve this, we have targeted expression of a switchable form of the c-Myc protein to the skin epidermis, a well characterized homeostatic tissue. We show that activation of c-MycER in adult suprabasal epidermis rapidly triggers proliferation and disrupts differentiation of postmitotic keratinocytes. Sustained activation of c-Myc is sufficient to induce papillomatosis together with angiogenesis--changes that resemble hyperplastic actinic keratosis, a commonly observed human precancerous epithelial lesion. All these premalignant changes spontaneously regress upon deactivation of c-MycER.

Invited review: effects of milk ration on solid feed intake, weaning, and performance in dairy heifers

A feeding regimen that allows a smooth transition from milk to solid feed is vital for successful heifer-rearing programs. In the past, research efforts have focused on the development of feeding methods that allow early weaning, perhaps because the risk of disease is highest during the milk feeding stage. To encourage early intake of calf starter, conventional feeding programs have limited the supply of milk (often to 10% of BW at birth). However, dairy calves provided free access to milk will typically consume more than twice this amount. We critically review the available literature examining the relationship between milk feeding method, solid feed consumption, and rumen development in young dairy calves and identify areas where new work is required. We conclude that milk-fed dairy calves can safely ingest milk at approximately 20% of body weight (BW)/d, and greater milk consumption supports greater BW gain, improved feed efficiency, reduced incidence of disease, and greater opportunity to express natural behaviors, which in combination suggest improved welfare. Method of weaning greatly influences feed consumption, rumen development, and growth check in calves provided higher amounts of milk. Gradual weaning encourages starter intake during the preweaning period, and both weaning age and duration of weaning influence this consumption. Increased solid feed consumption during the weaning process contributes to rumen development, permitting higher starter intake and BW gain after weaning. Growth factors in milk may also enhance the growth and maturation of the gastrointestinal tract, but more research is required to understand the role of these factors. Greater nutrient supply through increased amount of milk appears to improve immune function and long-term performance of heifer calves; for example, reducing the age at first breeding and increasing first-lactation milk yield, but more research is needed to confirm these effects.

Nanoparticle technology for drug delivery across the blood-brain barrier

Nanoparticles (NP) are solid colloidal particles ranging in size from 1 to 1000 nm that are utilized as drug delivery agents. The use of NPs to deliver drugs to the brain across the blood-brain barrier (BBB) may provide a significant advantage to current strategies. The primary advantage of NP carrier technology is that NPs mask the blood-brain barrier limiting characteristics of the therapeutic drug molecule. Furthermore, this system may slow drug release in the brain, decreasing peripheral toxicity. This review evaluates previous strategies of brain drug delivery, discusses NP transport across the BBB, and describes primary methods of NP preparation and characterization. Further, influencing manufacturing factors (type of polymers and surfactants, NP size, and the drug molecule) are detailed in relation to movement of the drug delivery agent across the BBB. Currently, reports evaluating NPs for brain delivery have studied anesthetic and chemotherapeutic agents. These studies are reviewed for efficacy and mechanisms of transport. Physiological factors such as phagocytic activity of the reticuloendothelial system and protein opsonization may limit the amount of brain delivered drug and methods to avoid these issues are also discussed. NP technology appears to have significant promise in delivering therapeutic molecules across the BBB.

Positron emission tomography scanning in the evaluation of hepatocellular carcinoma

BACKGROUND/AIMS

18F-fluorodeoxyglucose uptake allows estimation of glucose metabolism by tumor cells using positron emission tomography (PET). We evaluated the role of PET imaging in the diagnosis of hepatocellular carcinoma.

METHODS

PET images were collected after intravenous injection of 8-12 mCi of 18F-FDG in 20 patients with hepatocellular carcinoma (HCC). PET tumor activity level was assessed on a scale of 1 to 4 compared to normal liver tissue. The PET score was compared with abdominal computerized tomography (CT) scan results and between tumors of different grades and differentiation.

RESULTS

Of the 20 patients studied, 11 (55%) had positive PET scans (PET score: 3 or 4) while nine (45%) were negative (PET score: 1 or 2). CT scan was positive in 18 patients (90%) and negative in two (10%). PET, however, revealed metastases in three patients that were not seen on CT. On pathological review, well-differentiated and low-grade tumors had lower PET scores. Comparison of the well-differentiated with the moderately- and poorly-differentiated tumors revealed a statistically significant difference. No statistical significance was observed between the moderately- and poorly-differentiated tumors or between different tumor grades and PET scores.

CONCLUSIONS

The sensitivity of PET in diagnosis of HCC was 55% compared to 90% for CT scanning, although only PET detected some tumors (including distant metastases). Well-differentiated and low tumor grades had lower activity on PET and correspondingly lower PET scores. PET imaging may help assess tumor differentiation and may be useful in the diagnosis and staging and prognostication of HCC as an adjunct to CT.

Arthroscopic repair of full-thickness tears of the rotator cuff

We present the results of arthroscopic repair of full-thickness tears of the rotator cuff in seventy-three patients (thirty-nine men and thirty-four women). The average age of the patients at the time of the operation was 60.7 years (range, thirty-one to eighty-two years). All of the patients were followed for at least two years (average, thirty months; range, twenty-four to forty months). The shoulders were evaluated with the rating scale of the University of California at Los Angeles, the shoulder index of the American Shoulder and Elbow Surgeons, and the functional rating scale of Constant and Murley. In addition, the patients completed the Short-Form 36 Health Survey (SF-36) preoperatively and at the yearly follow-up evaluations. Eleven tears were small (less than one centimeter in length), forty-five were medium (one to three centimeters), eleven were large (more than three to five centimeters), and six were massive (more than five centimeters). The average length of the tear was twelve millimeters, and the average width was twenty-seven millimeters. Sixty-nine tendons were repaired anatomically, and four were repaired an average of three millimeters (range, two to eight millimeters) medial to the anatomical insertion of the tendon. An average of 2.3 (range, one to four) suture anchors were used in the repair. Sixty-three glenohumeral joints were normal, and ten had an intra-articular lesion. Seven patients had a concomitant resection of the acromioclavicular joint. The average duration of the operation was fifty-six minutes (range, thirty-five to ninety minutes). The active and passive ranges of motion improved significantly after the procedure (p = 0.0001). The strength of resisted elevation improved from 7.5 to 14.0 pounds (3.4 to 6.3 kilograms) (p = 0.0001). The average total score according to the rating scale of the University of California at Los Angeles improved from 12.4 to 31.1 points; the average total score according to the shoulder index of the American Shoulder and Elbow Surgeons, from 30.7 to 87.6 points; and the average absolute score according to the rating system of Constant and Murley, from 41.7 to 83.6 points (p = 0.0001 for all comparisons). The average score for the pain component of the rating scale of the University of California at Los Angeles improved from 2.4 to 8.6 points; fifty-seven (78 per cent) of the seventy-three patients rated the relief of pain as good or excellent on the visual-analog scale. The average score for satisfaction improved from 0.4 to 4.6 points; sixty-six patients (90 per cent) rated their satisfaction as good or excellent at the time of the most recent examination. None of the shoulders were rated as good or excellent before the operation, whereas sixty-one (84 per cent) were so rated at the most recent follow-up evaluation after the index procedure. In addition, significant improvements (p = 0.0015) were noted in the scales and summary measures of the SF-36. Arthroscopic repair of full-thickness tears of the rotator cuff produced satisfactory results with regard to traditional orthopaedic criteria as well as with regard to patient-assessed criteria such as satisfaction, pain relief, and general health. The arthroscopic method offers several advantages, including smaller incisions, access to the glenohumeral joint for the inspection and treatment of intra-articular lesions, no need for detachment of the deltoid, and less soft-tissue dissection. However, these advantages must be considered against the technical difficulty of the method, which limits its application to surgeons who are skilled in both open and arthroscopic procedures on the shoulder.

Primary structure of four allatostatins: neuropeptide inhibitors of juvenile hormone synthesis

Four neuropeptides that inhibit juvenile hormone synthesis by the corpora allata have been isolated from brains of the virgin female cockroach Diploptera punctata. These allatostatins are 8-13 amino acids long, are amidated, and show sequence similarity, including a 3-amino acid sequence at the C-terminal end that is common to all four peptides. The peptide sequences are as follows: allatostatin 1, Ala-Pro-Ser-Gly-Ala-Gln-Arg-Leu-Tyr-Gly-Phe-Gly-Leu-NH2; allatostatin 2, Gly-Asp-Gly-Arg-Leu-Tyr-Ala-Phe-Gly-Leu-NH2; allatostatin 3, Gly-Gly-Ser-Leu-Tyr-Ser-Phe-Gly-Leu-NH2; and allatostatin 4, Asp-Arg-Leu-Tyr-Ser-Phe-Gly-Leu-NH2. An in vitro bioassay of the synthesized allatostatins showed greater than 40% inhibition of juvenile hormone synthesis by corpora allata of virgin females with 10(-9) M allatostatin 1, 10(-8) M allatostatins 2 and 4, and 7 X 10(-7) M allatostatin 3. Inhibition by allatostatins 1-4 was reversible. In addition, allatostatin 1 inhibited juvenile hormone synthesis by corpora allata from mated females and last-instar larvae of D. punctata and corpora allata of adult female Periplaneta americana.

Invited review: Transitioning from milk to solid feed in dairy heifers

Calves are born with a physically and metabolically underdeveloped rumen and initially rely on milk to meet nutrient demands for maintenance and growth. Initiation of solid feed consumption, acquisition of anaerobic microbes, establishment of rumen fermentation, expansion of rumen in volume, differentiation and growth of papillae, development of absorption and metabolic pathways, maturation of salivary apparatus and development of rumination behavior are all needed as the calf shifts from dependence on milk to solid feed. In nature and some production systems (e.g., most beef calves), young ruminants obtain nutrients from milk and fresh forages. In intensive dairying, calves are typically fed restricted amounts of milk and weaned onto starter feeds. Here we review the empirical work on the role of feeding and management during the transition from milk to solid feed in establishing the rumen ecosystem, rumen fermentation, rumen development, rumination behavior, and growth of dairy calves. In recent years, several studies have illustrated the benefits of feeding more milk and group rearing of dairy calves to take advantage of social facilitation (e.g., housing with peers or dam), and this review also examines the role of solid feed on rumen development and growth of calves fed large quantities of milk and reared under different housing situations. We conclude that the provision of high-starch and low-fiber starter feeds may negatively affect rumen development and that forage supplementation is beneficial for promoting development of the gut and rumination behavior in young calves. It is important to note that both the physical form of starter diets and their nutritional composition affect various aspects of development in calves. Further research is warranted to identify an optimal balance between physically effective fiber and readily degradable carbohydrates in starter diets to support development of a healthy gut and rumen, rumination behavior, and growth in young calves.

Distinct short-lived and long-lived antibody-producing cell populations

This report analyzes the life span of Ig-containing cells (IgCC) in different sites of antibody production. The experimental approach was based upon the observations that most IgCC are derived from proliferating precursors while IgCC themselves are mainly nondividing end cells. Rats were given a continuous infusion of [3H] thymidine via an osmotic pump inserted in the peritoneal cavity. At intervals of 1, 3, 5 or 10 days after starting infusions, tissues were taken and analyzed by a combination of immunohistology and autoradiography to identify the proportions of IgCC which had gone through S phase of the cell cycle during the period of infusion. After 3 days infusion the median and (range) percent-labeled IgCC in the medullary cords of mesenteric and cervical lymph nodes and the red pulp of the spleen were, respectively, 88 (81-90), 75 (66-77) and 88 (82-93). Conversely that for IgCC in bone marrow was only 13 (11-17) and that in the lamina propria of the jejunum 47 (33-68). The rate of increase in labeling of bone marrow IgCC with length of infusion was approximately linear. Extrapolation of this slope suggests that bone marrow IgCC have a life span in excess of 3 weeks. The slopes of increase in IgCC labeled with time for lymph nodes and spleen were clearly biphasic suggesting that while most IgCC in these tissues have a life span of less than 3 days, there is also a minor population of long-lived IgCC. The lamina propria appears to have approximately equal proportions of long and short-lived IgCC. The life span of IgCC, with the exception of IgMCC, appears to be a feature of the site of antibody production rather than the Ig class produced. Almost all IgM-containing cells were found to be short lived.

A distinct picornavirus group identified by sequence analysis

Although echovirus 22 is presently classified as a member of the enterovirus group in the family of picornaviruses, it has been reported to have exceptional biological properties when compared with other representatives of the group. We have determined the complete nucleotide sequence of the echovirus 22 (Harris strain) genome, which appears to be significantly different from all the other studied picornaviruses. However, the organization of the genome [7339 nucleotides, excluding the poly(A) tract] is similar to that of previously sequenced picornaviruses. This genome includes a 5' untranslated region, relatively well-conserved when compared with aphtho- and cardioviruses, followed by an open reading frame coding for a 2180-amino acid-long polyprotein. The amino termini of capsid polypeptides VP1 and VP3 were determined by direct sequencing, and the other proteolytic cleavage sites in the polyprotein were predicted by comparison with other picornavirus proteins. The amino acid identities of echovirus 22 polypeptides with the corresponding proteins of other picornaviruses are in the 14-35% range, similar to those percentages seen when representatives of the five picornavirus groups (entero-, rhino-, cardio-, aphtho-, and hepatoviruses) are compared. Our results suggest that echovirus 22 belongs to an independent group of picornaviruses.

A subset of CD4+ memory T cells contains preformed CD40 ligand that is rapidly but transiently expressed on their surface after activation through the T cell receptor complex

Signaling through surface CD40 is essential for selecting B cells that have mutated their immunoglobulin variable region genes in germinal centers and is an important signal in the early stages of antibody responses to T cell-dependent antigens. It is shown that a subset of CD45RO+, CD4+ T cells isolated from human tonsil contains preformed 30-35-kD ligand for CD40. This is expressed on their surfaces within 5 min of their antigen-receptor complexes interacting with CD3 epsilon antibodies bound to ox erythrocytes. This surface expression does not require de novo protein synthesis and lasts for only 1-2 h. Preformed CD40 ligand (CD40L) was not detected in any CD4+ CD45RA+ T cells, but > 90% of all CD4+ T cells from the tonsil can be induced to express large amounts of CD40L on culture with phorbol myristate acetate and the calcium ionophore ionomycin. This expression of CD40L starts between 1 and 2 h, peaks at 6 h, and remains at a high level for > 20 h. It is totally prevented by adding a concentration of cycloheximide that inhibits CD25 synthesis by these activated cells. While CD3 epsilon antibody bound to ox red cells is a good inducer of surface expression of CD40L, it is a much less potent inducer of CD40L synthesis than phorbol myristate acetate with ionomycin. Immunohistological analysis of tonsil sections shows that cells containing CD40L are located mainly in the outer zone of germinal centers and the margins of the T zones that are rich in dendritic cells (interdigitating cells). The distribution of these cells is consistent with: (a) their interaction in T zones with B cells that have taken up and processed antigen and (b) their involvement in B cell selection in germinal centers.

The SAPHO syndrome

The occurrence of musculoskeletal manifestations (including synovitis, chest wall arthro-osteitis and multifocal aseptic osteomyelitis) in association with severe acne, palmoplantar pustulosis and perhaps with some presentations of psoriasis, have been described by many authors in the past 30 years. These different multifaceted descriptions have been designated by a variety of terms. More recently, a possible link between these conditions and spondarthritides has also been underlined by a slightly increased prevalence of HLA-B27 and occasional occurrences of sacroiliitis, chronic inflammatory bowel disease and possibly psoriasis. An acronym, the SAPHO syndrome (which stands for Synovitis, Acne, Pustulosis, Hyperostosis and Osteitis) is proposed for this group of diseases because of the similarity of musculoskeletal manifestations in patients with severe acne and pustulosis. The clinical, epidemiological, pathophysiological, immunogenetic and diagnostic aspects, as well as the management of this syndrome, are reviewed.

Pre- and Postweaning Performance of Holstein Female Calves Fed Milk Through Step-Down and Conventional Methods

Milk consumption, dry feed intake, body weight (BW) gain, occurrence of diarrhea, and selected blood metabolites were studied in female Holstein calves fed milk either through conventional or step-down (STEP) methods. In conventional method, the calves (n = 20) were fed colostrum and then milk at the rate of 10% of BW for the entire period of 45 d. In STEP method, the calves (n = 20) were given colostrum and then milk for 25 d at the rate of 20% of BW, which was reduced (between d 26 to 30) to 10% of BW for the remaining 15 d. The calves fed through conventional and STEP methods were weaned gradually by diluting milk with water between d 46 and 50. Feed intake and BW of the calves were monitored until 90 d of age. The STEP calves consumed 92.3, 19.4, and 62.4% more milk than conventionally fed calves during pre-STEP (d 1 to 30), post-STEP (d 31 to 50), and preweaning (d 1 to 50) periods, respectively. Consumption of starter and hay were greater during the pre-STEP period and lesser during the post-STEP and postweaning (d 51 to 90) periods in calves provided milk using conventional method compared with STEP-fed calves. Body weight gain, dry matter intake, and feed efficiency of calves were greater in those on the STEP method than on the conventional method. Lesser blood glucose and greater blood urea nitrogen at weaning (d 50) and postweaning (d 60) possibly indicated a better functioning rumen in calves fed milk through The STEP method than those fed conventionally. Occurrence of diarrhea was higher during wk 3 and 4 of age in calves fed milk through conventional method compared with STEP-fed calves. In conclusion, STEP milk feeding may prevent the problems of depressed solid feed intake associated with ad libitum milk feeding and of poor BW gain with conventional milk feeding in dairy calves.

Hay intake improves performance and rumen development of calves fed higher quantities of milk

Research to date has suggested that access to forage before weaning can limit rumen development in calves, but no research has yet addressed the role of forage for calves fed higher quantities of milk. This study compared performance and rumen development of calves provided high volumes (equivalent to approximately 20% of calf birth weight) of milk with and without access to hay. At d 3 of age, individually housed calves were randomly assigned to treatment (either ad libitum access to chopped grass hay or no forage; n=15 calves per treatment, 10 heifers, and 5 bulls). All calves were provided ad libitum access to water and starter throughout the study. All calves were offered 8L of milk/d from a nipple bottle from d 3 to 35, 4 L/d from d 36 to 53, and 2L/d until weaning at d 56. Solid feed intake and growth parameters were monitored from d 3 to 70. At d 70, males from both treatments were slaughtered to measure rumen development parameters. Overall dry matter (DM) intake from solid feed did not differ between treatments before wk 5. However, during wk 6 to 10, calves fed forage consumed more total DM (starter plus hay) than did calves fed no forage. Hip and wither height, heart girth, and body barrel at d 3, 56, and 70 did not differ between treatments. Reticulorumen weight was heavier in calves fed hay versus those fed only starter (12.77±1.29 vs. 7.99±0.69 kg with digesta; 1.89±0.05 vs.1.60±0.09 kg without digesta). Body weight without digesta was similar in calves fed forage or no forage. Mean rumen pH was higher in calves fed hay compared with those fed no forage (5.49±0.08 vs. 5.06±0.04). In conclusion, provision of chopped hay to calves fed high volumes of milk can promote solid feed DM intake and rumen development without affecting BW gain.