Progressive increase in body mass index is not associated with a progressive increase in joint space narrowing in obese women with osteoarthritis of the knee

OBJECTIVE

Given that obesity is a risk factor for osteoarthritis (OA) of the knee, a study was undertaken to determine whether progressively higher body mass index (BMI) among obese women is associated with progressive increases in joint space narrowing (JSN).

METHODS

Medial compartment JSN over 12 months in Lyon Schuss radiographs of 60 obese women (BMI 30.0-50.5 kg/m(2)) with radiographic and symptomatic OA was compared with that in 81 non-obese women (BMI <28 kg/m(2)) with normal radiographs and minimal or no symptoms of knee OA.

RESULTS

Among the patients with OA, higher BMI tended to be associated with a higher Kellgren and Lawrence (KL) grade of OA severity. JSN in the non-obese controls was negligible, but in the 30 patients with KL grade 2 and KL grade 3 knees, mean (SD) JSN was 0.12 (0.31) mm and 0.32 (0.50) mm, respectively (p<0.005 and p<0.001). No association was seen between baseline BMI and 12-month JSN in patients with OA; indeed, the regression plot suggested a slight inverse relationship between the two.

CONCLUSIONS

In obese patients with OA, progressively higher BMI values were not accompanied by a progressively increasing rate of JSN. Joint loading was not evaluated, but it is possible that marked obesity limited the functional capacity of some subjects with OA, protecting their knees from loading. For investigators considering eligibility criteria for a trial of a structure-modifying OA drug, these data suggest that recruitment of patients with a BMI much higher than 30 kg/m(2) will not enrich the sample of subjects who will have more rapid JSN than those with a BMI of only 30 kg/m(2).

How does a riverine setting affect the lifestyle of shellmound builders in Brazil?

The contact of inland and coastal prehistoric groups in Brazil is believed to have been restricted to regions with no geographical barrier, as is the case in the Ribeira de Iguape valley. The inland osteological collection from the riverine shellmound Moraes (5800-4500 BP) represents a unique opportunity to test this assumption for this region. Despite cultural similarities between riverine and coastal shellmounds, important ecological and site distribution differences are expected to impact on lifestyle. The purpose of this study is thus to document and interpret health and lifestyle indicators in Moraes in comparison to coastal shellmound groups. Specifically we test if the rare evidence of fish and mollusc remains in the riverine shellmound led to (a) higher caries rates and (b) lower auditory exostosis frequency and (c) if the small size of the riverine shellmound translates into reduced demographic density and thus rarity of communicable infectious diseases. Of the three hypotheses, (a) was confirmed, (b) was rejected and (c) was partly rejected. Bioanthropological similarities between Moraes and coastal shellmounds include auditory exostoses with equally high frequencies; significantly more frequent osteoarthritis in upper than in lower limbs; cranial and dental morphological affinities and low frequencies of violent trauma. However, there are also important differences: Moraes subsisted on a much broader protein diet and consumed more cariogenic food, but showed a stature even shorter than coastal groups. Thus, despite the contact also suggested by treponematoses in both site types, there was enough time for the people at the riverine site to adapt to local conditions.

Interleukin-21 stimulates antigen uptake, protease activity, survival and induction of CD4+ T cell proliferation by murine macrophages

Interleukin (IL)-21 is a T cell-derived cytokine which uses a heterodimeric receptor, composed of the common gamma-chain (CD132) and an IL-21Ralpha-chain. IL-21 activates lymphoid T and B cells, modulates antibody production but also suppresses maturation of myeloid dendritic cells; however, its role in the differentiation and function of other myeloid cells remains less clear. In this study we analysed IL-21/IL-21Ralpha effects on macrophage (MPhi) differentiation and function. MPhi could be generated readily from bone marrow with MPhi-colony-stimulating factor in the presence of IL-21 (designated IL-21MPhi) or from IL-21Ralpha-/- mice. IL-21Ralpha-/- mice had normal MPhi numbers, suggesting a non-essential role of both IL-21 and the IL-21Ralpha for MPhi generation. We could demonstrate that mature MPhi express the IL-21Ralpha and the common gamma-chain. However, short-term IL-21 stimulation did not enhance MPhi proliferation but induced anti-apoptotic cell-cycle regulators p21(waf1)/p27(Kip1) and expression of suppressors of cytokine signalling (SOCS)2/SOCS3. Moreover, IL-21 enhanced phagocytosis by MPhi via IL-21Ralpha signalling and supports protease activity and matrix metalloproteinase 12 expression. Stimulating MPhi with IL-21 enhanced their capacity to induce antigen-specific CD4+ T cell proliferation in dependence from the IL-21Ralpha, which was not the case for CD8+ T cells. Taken together, IL-21 plays a previously unrecognized role in modulating innate and acquired effector mechanisms of murine MPhi by linking these different functions to support CD4+ T cell-mediated immune responses.

Superiority of the Lyon schuss view over the standing anteroposterior view for detecting joint space narrowing, especially in the lateral tibiofemoral compartment, in early knee osteoarthritis

OBJECTIVE

To evaluate the validity of using the conventional anteroposterior (AP) radiograph of the knee in order to identify joint space narrowing (JSN) at an early stage of osteoarthritis (OA).

METHODS

Grading of JSN using a 0-5 score and quantitative measurement of joint space width (JSW) of the medial and lateral compartments of the tibiofemoral joint in AP and fluoroscopically assisted posteroanterior Lyon schuss (LS) radiographs of 202 patients with knee OA.

RESULTS

Knees without definite JSN (score <2) were twice as common in AP than in LS radiographs (36.1% vs 18.8%). The number of knees showing definite medial JSN was identical in both views but four knees showing a medial OA in AP view were classified differently in the LS radiographs (three bicompartmental OA and one lateral OA). The frequency of lateral JSN was approximately twice as great in the LS view as in the AP view. JSN score was significantly higher (p<0.001) and JSW was significantly smaller (p<0.01) in the LS view than in the AP view. In knees with definite JSN, JSW of the compartment with no narrowing was significantly (p<0.04) larger than in knees that did not exhibit definite JSN. Medial JSW and lateral JSW were inversely correlated (p<0.001).

CONCLUSIONS

The standing AP radiograph performed poorly in identifying both the location of JSN in patients with early tibiofemoral OA (especially, lateral OA) and the severity of JSN. The LS radiographs are preferable to standing AP views for the selection of patients for therapeutic trials of structure-modifying OA drugs.

Assessment of the radioanatomic positioning of the osteoarthritic knee in serial radiographs: comparison of three acquisition techniques

OBJECTIVE

Recent studies using various standardized radiographic acquisition techniques have demonstrated the necessity of reproducible radioanatomic alignment of the knee to assure precise measurements of medial tibiofemoral joint space width (JSW). The objective of the present study was to characterize the longitudinal performance of several acquisition techniques with respect to long-term reproducibility of positioning of the knee, and the impact of changes in positioning on the rate and variability of joint space narrowing (JSN).

METHODS

Eighty subjects were randomly selected from each of three cohorts followed in recent studies of the radiographic progression of knee osteoarthritis (OA): the Health ABC study (paired fixed-flexion [FF] radiographs taken at a 36-month interval); the Glucosamine Arthritis Intervention Trial (GAIT) (paired metatarsophalangeal [MTP] radiographs obtained at a 12-month interval), and a randomized clinical trial of doxycycline (fluoroscopically assisted semiflexed anteroposterior (AP) radiographs taken at a 16-month interval). Manual measurements were obtained from each radiograph to represent markers of radioanatomic positioning of the knee (alignment of the medial tibial plateau and X-ray beam, knee rotation, femorotibial angle) and to evaluate minimum JSW (mJSW) in the medial tibiofemoral compartment. The effects on the mean annualized rate of JSN and on the variability of that rate of highly reproduced vs variable positioning of the knee in serial radiographs were evaluated.

RESULTS

Parallel or near-parallel alignment was achieved significantly more frequently with the fluoroscopically guided positioning used in the semiflexed AP protocol than with either the non-fluoroscopic FF or MTP protocol (68% vs 14% for both FF and MTP protocols when measured at the midpoint of the medial compartment; 75% vs 26% and 34% for the FF and MTP protocols, respectively, when measured at the site of mJSW; P<0.001 for each). Knee rotation was reproduced more frequently in semiflexed AP radiographs than in FF radiographs (66% vs 45%, P<0.01). In contrast, the FF technique yielded a greater proportion of paired radiographs in which the femorotibial angle was accurately reproduced than the semiflexed AP or MTP protocol (78% vs 59% and 56%, respectively, P<0.01 for each). Notably, only paired radiographs with parallel or near-parallel alignment exhibited a mean rate of JSN (+/-SD) in the OA knee that was more rapid and less variable than that measured in all knees (0.186+/-0.274 mm/year, standardized response to mean [SRM]=0.68 vs 0.128+/-0.291 mm/year, SRM=0.44).

CONCLUSION

This study confirms the importance of parallel radioanatomic alignment of the anterior and posterior margins of the medial tibial plateau in detecting JSN in subjects with knee OA. The use of radiographic methods that assure parallel alignment during serial X-ray examinations will permit the design of more efficient studies of biomarkers of OA progression and of structure modification in knee OA.

The genome of the virulent phage Lc-Nu of probiotic Lactobacillus rhamnosus, and comparative genomics with Lactobacillus casei phages

The complete 36,466-bp genome sequence of the virulent phage Lc-Nu of probiotic Lactobacillus rhamnosus was determined. The linear dsDNA with a GC-content of 44.2% contained 3' single-stranded cohesive ends of 12 nucleotides. A total of 51 putative open reading frames (orfs) were predicted. Lc-Nu showed to be evolutionary closely related to the temperate Lactobacillus casei phages phi AT3 and A2. High DNA homology with phi AT3 was shared over the late transcribed genes, and the highest homology with A2 was within the genetic switch region. The truncated cI-like repressor was the only lysogeny related gene left, which strongly suggested Lc-Nu to be recently evolved from a temperate origin. Three putative methylases and endonucleases were detected from the region of early-transcribed genes. The putative origin of replication within the putative gene orf34 homologous to replisome organizers resembled to that of lambdoid phages. The present study suggested Lc-Nu to be a new candidate for the proposed Sfi21-like species.

Intracranial epidermoid cyst in a horse

An intracranial epidermoid cyst was diagnosed in a Haflinger gelding aged 12 years suffering from episodes of neurological disturbance, apathy and fever. The extracerebral cyst was located in the region of the tentorium cerebelli and measured 9 x 8 x 5 cm. It displaced the cerebral hemispheres anteriorly and compressed the cerebellum and brainstem underneath. Histologically, the cyst was lined by keratinizing, stratified squamous epithelium and contained keratin scales, debris, focal haemorrhages, and degenerating inflammatory cells. The epithelium was supported by a vascularized fibrous capsule that firmly adhered to the dura mater. Multifocal haemorrhages and moderate lymphohistiocytic infiltrations were present in the capsule. The basement membrane was disrupted focally, and single or clustered cytokeratin-positive epithelial cells were detected in the fibrous capsule, suggesting a possible transition to malignancy.

Flavone C-glycoside, phenolic acid, and nitrogen contents in leaves of barley subject to organic fertilization treatments

From the leaves of barley, Hordeum vulgare, one new flavone C-glucoside and three known flavone glucosides were isolated and characterized by (1)H and (13)C NMR and MALDI-TOF-MS. The novel flavone C-glucoside was isovitexin 7-O-beta-[6' "-O-(E)-p-coumaroyl]glucoside (6' "-coumaroylsaponarin), and the known compounds were isovitexin 7-O-beta-[6' "-O-(E)-feruloyl]glucoside, isoorientin 7-O-beta-[6' "-O-(E)-feruloyl]glucoside, and tricin 7-O-beta-glucoside. The sum of all the flavone glycosides and soluble phenolic acids in the leaves decreased with increased rate of plant nutrients given in animal manure and with increased crop yield. All of the major phenylpropanoids showed the same general response to nutrient level. The concentration of nitrogen in the leaves was not directly related to nutrient application or to contents of phenylpropanoids.

TSST-1 induces Th1 or Th2 differentiation in naïve CD4+ T cells in a dose- and APC-dependent manner

Superantigens are potent activators of the immune system, causing a variety of diseases, ranging from food poisoning to septic shock. Here, we examined the effects of different toxic shock syndrome toxin 1 (TSST-1) concentrations on the activation, proliferation and synthesis of interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) in purified naïve human CD4+ T cells in a serum-free in vitro system. TSST-1 given in low doses (1-10 pg/ml) generates a pronounced T helper 2 (Th2)-like cytokine profile, characterized by elevated IL-4-expressing T-cell populations and reduced IFN-gamma-producing populations, whereas higher doses (100 pg/ml) induce a Th1-like profile, with increased expression of IFN-gamma and reduced expression of IL-4. These patterns were even more pronounced by adding exogenous cytokines like IL-12 and IL-4 and by the type of antigen-presenting cells (APCs). Thus, B cells induced Th2 shifts, whereas monocytes favoured Th1 induction. Moreover, IL-12 in conditions with B cells counteracted their Th2 bias. Interestingly, in purified naïve T-cell cultures, containing a small population of HLA-DR+ T cells, Th1/Th2 differentiation can be induced by TSST-1 too. There, Th-cell polarization is strongly dependent on TSST-1 concentration, indicating that this is a key parameter in regulating the differentiation of T cells. In conclusion, our data show that Th1/Th2 differentiation of TSST-1-stimulated naïve T cells is controlled by the type of APCs, and in APC-depleted cultures, it depends on the presence of HLA-DR+ cells and TSST-1 concentration.

Characterization of the eugenol hydroxylase genes (ehyA/ehyB) from the new eugenol-degrading Pseudomonas sp. strain OPS1

During the screening for bacteria capable of converting eugenol to vanillin, strain OPS1 was isolated, which was identified as a new Pseudomonas species by 16 s rDNA sequence analysis. When this bacterium was grown on eugenol, the intermediates, coniferyl alcohol, ferulic acid, vanillic acid, and protocatechuic acid, were identified in the culture supernatant. The genes encoding the eugenol hydroxylase (ehyA, ehyB), which catalyzes the first step of this biotransformation, were identified in a genomic library of Pseudomonas sp. strain OPS1 by complementation of the eugenol-negative mutant SK6165 of Pseudomonas sp. strain HR199. EhyA and EhyB exhibited 57% and 85% amino acid identity to the eugenol hydroxylase subunits of Pseudomonas sp. strain HR199 and up to 34% and 54% identity to the corresponding subunits of p-cresol methylhydroxylase from P. putida. Moreover, the amino-terminal sequences of the alpha- and beta-subunits reported recently for an eugenol dehydrogenase of P fluorescens E118 corresponded well with the appropriate regions of EhyA and EhyB. Downstream of ehyB, an open reading frame was identified, whose deduced amino acid sequence exhibited up to 71% identity to azurins, representing most probably the gene (azu) of the physiological electron acceptor of the eugenol hydroxylase. The eugenol hydroxylase genes were amplified by PCR, cloned, and functionally expressed in Escherichia coli.

Comparison of Chemicon SimulFluor direct fluorescent antibody staining with cell culture and shell vial direct immunoperoxidase staining for detection of herpes simplex virus and with cytospin direct immunofluorescence staining for detection of varicella-zoster virus

A new rapid direct immunofluorescence assay, the SimulFluor direct fluorescent-antibody (DFA) assay, which can simultaneously detect herpes simplex virus types 1 and 2 (HSV-1 and -2) and varicella-zoster virus (VZV), was evaluated in comparison with our current standard procedures of (i) shell vial direct immunoperoxidase (shell vial IP) staining and cell culture for detection of HSV and (ii) cytospin DFA staining for VZV detection. A total of 517 vesicular, oral, genital, and skin lesion specimens were tested by all three procedures. For HSV detection, the SimulFluor DFA assay had an overall sensitivity, specificity, positive predictive value, and negative predictive value of 80.0, 98.3, 92.3, and 95.1%, respectively, when compared to culture. Shell vial IP staining had a sensitivity, specificity, positive predictive value, and negative predictive value of 87.6, 100, 100, and 96.9%, respectively, when compared with cell culture. The SimulFluor DFA assay, however, offers same-day, 1.5-hours results versus a 1- to 2-day wait for shell vial IP staining results and a 1- to 6-day wait for culture results for HSV. For VZV detection SimulFluor DFA staining detected 27 positive specimens as compared to 31 by our standard cytospin DFA technique--a correlation of 87.1%. A positive SimulFluor reaction for VZV is indicated by yellow-gold fluorescence compared to the bright apple-green fluorescence observed by cytospin DFA staining. There is no difference in turnaround time between the two assays. The SimulFluor DFA assay is a rapid immunofluorescence assay that can detect 80% of the HSV-positive specimens and 87% of the VZV-positive specimens with a 1.5-h turnaround time.

Supramolecular assistance to regioselectivity in the reactions of chlorocyclophosphazenes with sodium oxyanions: macrocyclic effect and anion dependence

Comparative studies of the naphtholysis of crown-bearing tetrachlorocyclotriphosphazene 2 and its acyclic analogue, nongem-diethoxytetrachlorocyclotriphosphazene 5 (which was synthesized and isolated in the pure cis form for the purpose of this study), reveal a significant macrocyclic effect of the substituent on both the kinetics and regiochemistry of chlorine substitution in the N(3)P(3) ring. Whereas substitution of 5 with sodium naphthoxide provided moderate yields of the respective sterically and electronically favored nongem-naphthoxydiethoxy derivative as the major product, isolated as the mixture of cis and trans isomers 8 + 9, the corresponding reaction of crown substrate 2 resulted in highly regioselective formation of the gem-to-macrocycle substituted mononaphthoxy PNP-crown derivative 11a. The importance of the PNP-crown related effects for the regio- and stereocontrol of the substitution of chlorine atoms in the N(3)P(3) ring is discussed in terms of supramolecular sodium cation-assisted interactions between the ring oxy substituent(s) and incoming oxyanions. To approach the problem of the anion-dependence of the regioselectivity, a comparison has been drawn between the reactions of the PNP-crown substrate 2 with sodium arylates derived from beta-naphthol (10a) and phenol (10b), carried out with equimolar or 100% excess sodium oxyanion with respect to 2, and the corresponding reactions of 2 with sodium monoenolates derived from the beta-dicarbonyl compounds: acetylacetone (10c) and ethyl acetylacetate (10d). The effectiveness of supramolecularly assisted transition state stabilization is found to be dependent not only on the dimensional complementarity between the cation and the macrocycle but also on the properties of the four interacting ionic centers according to the HSAB principle and on the nature of the electronic interaction of the PNP-crown substituent with the N(3)P(3) ring, the latter determining the extent of regiocontrol to either one or two macrocyclic chloride functions. The increase of the extent of regioselectivity of gem-substitution at the PNP-macrocycle when passing from arylate to beta-dicarbonyl enolate oxy anions is related to the observed trends in the (31)P NMR chemical shifts and refers to the electronic structure of the oxy substituent.

Structure-property relationships of a tetrapyrrolidinyl PNP-lariat ether and its complexes with potassium, sodium, and silver cations

Spectral properties of the tetrapyrrolidinyl PNP-lariat ether, L, and its complexes with K+, Na+, and Ag+ were investigated. Crystal structures of L and its complex with potassium iodide [KL]I were determined. Protonation constants of the ligand and formation constants of its complexes with Ag+, K+, and Na+ in aqueous solutions were determined. 1H NMR, 31P NMR, FTIR, and ESIMS spectra as well as potentiometric measurements indicate that complexation of Ag+ involves participation of the polyether oxygen donors and the endocyclic nitrogen atom of the cyclophosphazene ring. On the other hand, for complexation of K+ and Na+, only polyether oxygen atoms are involved. The latter conclusion is confirmed in the solid-state structure of the [KL]I complex.