Association of patellar bone marrow lesions with knee pain, patellar cartilage defect and patellar cartilage volume loss in older adults: a cohort study

AIM

To examine the cross-sectional and longitudinal associations of patellar bone marrow lesion (BMLs) with knee pain, cartilage defects and cartilage volume in older adults.

METHODS

A total of 904 randomly selected subjects (mean 62.4 years, 49.9% female) were studied. Fat suppressed T1-weighted spoiled gradient recall and T2-weighted fast spin echo magnetic resonance imaging (MRI) sequences were used to assess cartilage volume, cartilage defects and/or BMLs at baseline (n = 904) and 2.6 (range: 1.4-4.8) years' follow-up (n = 414). Knee pain was assessed by self-administered Western Ontario McMaster Osteoarthritis Index (WOMAC) questionnaire at baseline (n = 904) and follow-up (n = 790).

RESULTS

The prevalence of any patellar BMLs was 19% and was higher in those with tibiofemoral BMLs. In multivariable analyses, patellar BMLs were positively associated with any knee pain at baseline and an increase in knee pain when going up/down stairs (odds ratio (OR): 1.67, 95% confidence interval (CI): 1.08, 2.59) but not with other knee pain subscales. Patella BMLs were also associated with patellar cartilage defects both at baseline and change over time (OR: 1.76, 95% CI: 1.00, 3.70) but not tibiofemoral defects. Patellar BMLs were negatively associated with baseline and change in patella cartilage volume (β: -2.10%, 95% CI: -3.39%, -0.80%). These associations remained significant after further adjustment for tibiofemoral BMLs.

CONCLUSIONS

Patellar BMLs were consistently associated with increased knee pain especially going up/down stairs, increased patellar cartilage defects, and decreased patellar cartilage volume cross-sectionally and longitudinally, suggesting a predominantly compartment specific role for patellar BMLs.

Association between DEFB103 gene copy number variation and ankylosing spondylitis: a case-control study

In this brief communication, we investigate the role of DEFB103 gene copy number variation (CNV) in ankylosing spondylitis (AS) susceptibility. A total of 807 Chinese individuals including 406 AS patients and 401 controls were enrolled. The DEFB103 copy number was measured by two sets of probes to obtain a stable result in a custom-by-design Multiplex AccuCopy(™) kit (Genesky Biotechnologies Inc., Shanghai, China) based on a multiplex fluorescence competitive polymerase chain reaction (PCR) principle. The copy number of DEFB103 ranged from 2 to 6 in both AS patients and controls. Mann-Whitney U test and chi-squared test were performed to analyze the difference of DEFB103 copy number between AS patients and controls while no statistical difference has been found. We considered the copy number of DEFB103 gene may not associate with susceptibility to AS.

Correlation between the BRAF V600E mutation status and the clinicopathologic features of papillary thyroid carcinoma

This study sought to investigate the correlations of V-raf murine sarcoma viral oncogene homolog B1 (BRAF) gene mutations with the clinicopathologic features of papillary thyroid carcinoma and central lymph node metastasis. We retrospectively analyzed the 2-year medical records of patients who underwent surgery for papillary thyroid carcinoma. After screening, the records of 126 patients who met the study requirements were used to assess the characteristics associated with the BRAF V600E gene mutation. The BRAF mutation incidence rate among patients with papillary thyroid carcinoma was 69.0% (87/126). Univariate analysis revealed that the BRAF mutation status was correlated significantly with both tumor size and lymph node metastasis (P < 0.05). Multivariate analysis revealed a significant correlation between lymph node metastasis and BRAF mutation status (P < 0.05). When the tumor diameter was ≤10 mm, the BRAF mutation status had no effect on lymph node metastasis (P > 0.05). When the tumor diameter was >10 mm, the incidence of lymph node metastasis was significantly higher among BRAF mutation-positive patients than among BRAF mutation-negative patients (P < 0.05). BRAF gene mutations independently predicted central lymph node metastasis in patients with papillary thyroid carcinoma. For patients preoperatively diagnosed to be BRAF mutation-positive, the importance of central lymph node dissection should be emphasized because the tumor diameter increases; regional lymphatic and adipose tissue dissection should be routinely conducted. However, in mutation-negative patients with tumor diameters of ≤5 mm, the need for central lymph node dissection should be re-examined.

The status of research into resistance to diet-induced obesity

Obesity resistance is an increasingly popular area of study in academia, although the factors that lead to the occurrence of obesity resistance remain unclear. In this review, we discuss the currently known causes of obesity resistance. By comparing the differences between obesity-resistant individuals and obesity-susceptible individuals, researchers have identified the characteristics of obesity-resistant individuals. The primary approach has been to breed rats and mice with a high-fat diet and to compare the differences between obesity-resistant and obesity-susceptible individuals. The characterized differences have included gastrointestinal fat absorption, appetite, physical activity, fat storage, and fat consumption. Considerably more research is needed into the mechanisms of obesity resistance that could be used to lose weight among human subjects. However, there are few ongoing obesity resistance studies. Due to the relatively slow rate of development in this field, greater efforts must be applied in this area.

Which is more suitable for kidney transplantation at the early post-transplantation phase in China - low dosing or standard dosing of enteric-coated mycophenolate sodium?

AIMS

To investigate the pharmacokinetics of enteric-coated mycophenolate sodium (EC-MPS) and the clinical outcome in kidney transplant recipients in the early post-transplantation phase. Then explain which regimen is more suitable for Chinese renal transplant recipients.

METHODOLOGY

In total, 60 de novo kidney transplant recipients treated with tacrolimus and steroids were randomised to receive EC-MPS at standard dose (SD; 1440 mg/day; n = 28) or low dose (LD; 1080 mg/day; n = 32). Efficacy parameters, safety and tolerability were assessed over a 6-month study period. Full mycophenolic acid (MPA) areas under the curve (AUCs) were completed on days 3 and 5, whereas a three-point limited sampling strategy (LSS) was utilised for MPA AUC assessments at 2 weeks and months 1, 3 and 6 (the LSS for three-time-point MPA AUC 0-12 h (mg h/l) = 15.99 + 0.87C1 h  + 0.68C2 h  + 7.85C4 h ; r(2)  = 0.8670.

RESULTS

The mean AUC levels at day 3 and day 5 in the SD group were significantly higher than in the LD group (57.4 mg·h/l vs. 38.2 mg·h/l and 59.3 mg·h/l vs. 44.8 mg·h/l, respectively, p < 0.01). There was a trend for fewer clinically diagnosed acute rejections in the SD group vs. the LD group at 6 months (7.1% vs. 12.5%). This trend was also present when acute rejection was analysed as biopsy-proven cases. There were significantly more acute rejections (all definitions) in patients with MPA AUC levels < 30 mg·h/l compared with those with MPA AUC levels ≥ 30 mg·h/l within 6 months (p < 0.05). Renal function, incidence of infection and haematological disorders were not significantly different in either study group.

CONCLUSIONS

Early adequate MPA exposure in renal transplant recipients can be achieved with a higher starting dose. In addition, a SD regimen was as well-tolerated as a LD regimen. Furthermore, early adequate MPA exposure significantly lowered the rate of acute rejection without compromising safety and tolerability.

Familial effects on structural changes relevant to knee osteoarthritis: a prospective cohort study

OBJECTIVE

Genetic factors play an important role in the pathogenesis of knee osteoarthritis (OA), but which knee structural changes mediate this is unclear. This study aimed to describe the differences in knee structural changes over 8-10 years between offspring having at least one parent with total knee replacement (TKR) for severe primary knee OA and controls with no family history of knee OA.

DESIGN

115 offspring (mean age 45 years) with a family history of TKR for severe knee OA were compared with 104 (mean age 46 years) controls. T1 or T2-weighted fat saturated magnetic resonance imaging (MRI) was performed respectively to evaluate knee cartilage defects, bone marrow lesions (BMLs), meniscal extrusion and tears at baseline and 10 years. Multivariate logistic regression model was used to adjust for potential confounders.

RESULTS

Offspring had a greater increase in cartilage defect score (1.03 vs 0.52, P = 0.007) and meniscal extrusion score (0.28 vs 0.10, P = 0.027) over 10 years, and a greater increase in meniscal tear score (0.40 vs 0.10, P = 0.012) over 8 years in the medial but not the lateral tibiofemoral compartment. Changes in BMLs over 8-years were not different between the two groups. These associations were independent of potential confounders, and strengthened after further adjustment for each other.

CONCLUSION

With the exception of BMLs, offspring with a family history of knee OA have a greater risk of increases in multiple knee structural abnormalities in the medial tibiofemoral compartment suggesting pleiotropic familial effects.

Gene silencing of non-obese diabetic receptor family (NLRP3) protects against the sepsis-induced hyper-bile acidaemia in a rat model

The role of NOD-like receptor family (NLRP3) has been confirmed in various inflammatory diseases. The association between NLRP3 and hyper-bileacidaemia during the sepsis remains unclear. We aimed to investigate whether NLRP3 silencing protects against the sepsis-induced hyper-bileacidaemia. Sepsis was induced by caecum ligation and puncture (CLP). Gene silencing of NLRP3 was performed by injecting rats with NLRP3 short hairpin RNA plasmids (NLRP3 shRNA) 48 h before surgery. Rats were divided into four groups: group 1: sham; group 2: sepsis; group 3: NLRP3 shRNA + sepsis (called the 'NLRP3 shRNA' group); and group 4: scrambled shRNA + sepsis (called the 'scrambled shRNA' group). The serum levels of bile acids, hepatic expression of hepatocyte membrane transporters, hepatic cytokine levels and behaviours of immune cells were compared among the groups. Hepatic NLRP3 expression was increased dramatically during the sepsis, but was suppressed by pretreatment with NLRP3 shRNA. Compared with rats in the sepsis and the scrambled shRNA groups, rats in the NLRP3 shRNA group exhibited significantly decreased serum levels of glycine and taurine conjugated-bile acids, with rehabilitated expression of hepatocyte transporters, suppressed hepatic cytokine levels, decreased hepatic neutrophils infiltration and attenuated macrophages pyroptosis. Gene silencing of NLRP3 ameliorates sepsis-induced hyper-bileacidaemia by rehabilitating hepatocyte transporter expression, reducing hepatic cytokine levels, neutrophil infiltration and macrophages pyroptosis. NLRP3 may be a pivotal target for sepsis management.

A family history of knee joint replacement increases the progression of knee radiographic osteoarthritis and medial tibial cartilage volume loss over 10 years

OBJECTIVES

Osteoarthritis (OA) has a genetic component but it is uncertain if the offspring of those with knee OA are at a greater risk. The aim of this study was to describe radiographic OA (ROA) progression and cartilage loss over 10 years in a midlife cohort with some having a family history of OA and some community based controls.

METHODS

220 participants [mean-age 45 (26-61); 57% female] were studied at baseline and 10 years. Half were adult offspring of subjects who underwent knee replacement for OA and the remainder were randomly selected controls. Joint space narrowing (JSN) and osteophytes were assessed on radiographs and cartilage volume (tibial, femoral and patellar), cartilage defects, bone marrow lesions (BMLs) and meniscal tears were assessed on Magnetic resonance imaging (MRI).

RESULTS

For ROA, there was a significant difference between offspring and controls in unadjusted analysis for change in total ROA, medial JSN, total medial, total lateral and total osteophyte scores. This difference persisted for medial JSN (difference in ratios = +1.93 (+1.04, +3.51)) only, after adjustment for confounders and baseline differences. In unadjusted analysis for cartilage loss, offspring lost more cartilage at the medial tibial (difference in means = -79.13 (-161.92, +3.71)) site only. This difference became of borderline significance after adjustment for baseline differences (P = 0.055).

CONCLUSION

The offspring of subjects having a total knee replacement have a greater worsening of ROA (both JSN and osteophytes) and higher medial tibial cartilage volume loss over 10 years. Most of these changes are mediated by differences in baseline characteristics of offspring and controls except for increase in medial JSN.

Effects of tetracycline on simultaneous biological wastewater nitrogen and phosphorus removal

The presence of 2 and 5 mg L⁻¹of tetracycline decreased total nitrogen removal. Tetracycline induced EPS release and decreased its protective role on cells. Denitrifiers instead of nitrifiers were negatively affected by tetracycline.

Metabolic triggered inflammation in osteoarthritis

Osteoarthritis (OA) is a common chronic joint disorder with a multifactorial etiology including genetic and environmental factors. Metabolic triggered inflammation, induced by nutrient overload and metabolic surplus, consists of components such as obesity, pro-inflammatory cytokines and adipokines, abnormal metabolites, acute phase proteins, vitamin D deficiency, and deregulated microRNAs that may play a role in OA pathophysiology. Obesity-related metabolic factors, especially adipokines, contribute to OA development by inducing pro-inflammatory cytokines and degradative enzymes, leading to cartilage matrix impairment and subchondral bone remodeling. Ectopic metabolite deposition and low-grade systemic inflammation can contribute to a toxic internal environment that exacerbates OA. Complement components highly expressed in osteoarthritic joints have also been proposed as causative factors. Vitamin D deficiency has been associated with obesity and is implicated to be associated with cartilage loss in OA. Metabolic microRNAs may explain the inflammatory link between obesity and OA. Therapies targeting metabolic-triggered inflammation and its components are anticipated to have potential for the treatment of OA.

Mass effect and signal intensity alteration in the suprapatellar fat pad: associations with knee symptoms and structure

OBJECTIVE

To describe cross-sectional associations between mass effect or signal intensity alteration of the suprapatellar fat pad (SPFP) with knee symptoms and structure in older adults.

METHODS

A cross-sectional sample of 904 randomly selected subjects (mean 62.4 years, 49.9% female) was studied. T1- or T2-weighted fat suppressed magnetic resonance imaging (MRI) was used to assess mass effect or signal intensity alteration of SPFP, cartilage volume, cartilage defects, and bone marrow lesions (BMLs). Knee pain was assessed by self-administered Western Ontario McMaster Osteoarthritis Index (WOMAC) questionnaire. The Osteoarthritis Research Society International (OARSI) atlas was used to assess knee osteophyte, joint space narrowing (JSN) and radiographic osteoarthritis (ROA). Univariable and multivariable linear or logistic regression analyses were used to examine the associations.

RESULTS

After adjustment for confounders including age, sex, body mass index (BMI), disease status, tibial bone area and/or ROA, the presence of SPFP mass effect was significantly associated with any knee pain (OR: 2.39; 95% confidence interval (CI): 1.54, 3.70) and ROA (OR: 2.10; 95% CI: 1.33, 3.31) but not with cartilage volume, cartilage defects or BMLs. The presence of SPFP signal intensity alteration was significantly associated with any knee pain (OR: 1.90; 95% CI: 1.43, 2.53), ROA (OR: 1.83; 95% CI: 1.37, 2.45), any BMLs (OR: 1.55; 95% CI: 1.17, 2.06) but not with cartilage volume and cartilage defects. Significant associations with knee pain and BMLs were more evident in subjects with ROA. Presence of SPFP mass effect and/or signal intensity alteration combined was associated with any tibial cartilage defects (OR: 1.45; 95% CI: 1.04, 2.04).

CONCLUSIONS

SPFP mass effect and/or signal intensity alterations are deleteriously associated with knee pain, radiographic OA and BMLs in this cross-sectional study, suggesting that SPFP abnormalities may contribute to pain and structural abnormalities in the knee.