Primary sensory neurons with dichotomizing axons projecting to the facet joint and the low back muscle in rats

Background

Clinically, the origin of low back pain is unknown. The pain may originate from the lumbar muscles directly, or it may be referred pain from the spine. Dorsal root ganglion (DRG) neurons with dichotomizing axons have been reported in several species and are thought to be related to referred pain. However, these neurons, which have dichotomizing axons to the lumbar facet joints and to the lumbar muscle, have not been fully investigated.

Methods

Two neurotracers — 1,1′-dioctadecyl-3,3,3′,3′- tetramethyl-indocarbocyanine perchlorate (DiI) and fluorogold (FG) — were used in the present double-labeling study. DiI crystals were placed in the right L5/6 facet joint, and FG was applied to right multifidus muscles at the L5 level in 10 rats. Two weeks later, bilateral DRGs from L1 through L6 were harvested, sectioned, and observed under a fluorescence microscope.

Results

DiI-labeled DRG neurons innervating the L5/6 facet joint (5.17% of the total DRG neurons) were distributed from L1 to L6. FG-labeled DRG neurons innervating the lower back muscle (15.9% of the total) were also distributed from L1 to L6. Double-labeled DRG neurons were found from L1 to L6. The ratio of total double-labeled/total DiI-labeled DRG neurons was 17% and that of total double-labeled/total FG-labeled DRG neurons was 7%. Approximately 17% of all DRG neurons innervating the facet joints had other axons that extended to the lower back muscle.

Conclusions

This finding provides a possible neuroanatomical explanation for referred low back muscle pain from the lower facet joints.     

HLA-DPB1*0202 is associated with a predictor of good prognosis of Graves' disease in the Japanese

Whereas most patients with Graves' disease (GD) have antibodies against the thyrotropin receptor, which are measured as thyrotropin-binding inhibitory immunoglobulin (TBII), the TBII of 10% or less of Japanese patients with GD is undetectable at the first visit and throughout the entire clinical course, and these patients tend to respond well to medications and follow the better clinical course. Therefore, the absence of TBII at the first visit may be a predictor of good prognosis. Ninety-seven patients with GD who had remained TBII negative for at least 2 years from the onset, as well as 142 typical TBII-positive GD patients, were examined to reveal the HLA-linked immunogenetic background for this predictor. Compared with a healthy control population, the frequencies of HLA-A*0206 (OR=2.17, p=9.73x10(-4)) and DPB1*0501 (OR=3.26, p=3.31x10(-7)) carriers were increased in the typical patients, whereas those of HLA-A*0201 (OR=2.16, p=1.92x10(-3)), A*0207 (OR=3.19, p=7.17x10(-4)), and DPB1*0202 (OR=3.13, p=3.97x10(-4)) were increased in the TBII-negative group. These two patient groups were associated with similar HLA-A alleles and different HLA-DPB1 alleles, suggesting the presence of two genetic factors for GD within the HLA region; one is HLA-A linked and may be related to thyroid organ specificity, the other is HLA-DP linked and may control the severity of autoimmunity.     

Inequality and unwillingness to care for people living with HIV/AIDS: a survey of medical professionals in Southeast China

This study was aimed at assessing physicians' and physician assistants' knowledge and attitudes toward HIV/AIDS and identifying determinants of willingness to care for infected individuals in Southeast China. From May to June 2004, 454 physicians and physician assistants from 5 different medical facility levels in Fujian Province, China, undertook a survey on knowledge, attitude, behavior, and practice (KABP). Only 40.4% (95% confidence intervals: 35.9, 44.9) were willing to provide healthcare services for people living with HIV/AIDS (PLWHAs). Knowledge (p < 0.001) and attitude scores (p = 0.01) as well as the proportion of those willing to provide care (p < 0.001) significantly differed by facility level. Multivariate analysis identified supportive attitudes toward PLWHAs (p < 0.001), self-confidence in providing care (p < 0.001), and facility level as significant predictors of willingness to care for infected individuals. Village medical stations showed the most unfavorable outcomes. Enhanced education as well as specific programs promoting supportive attitudes and willingness to care is therefore required, especially among those working at lower facility levels in remote areas.     

Disseminated Mycobacterium marinum infection in a patient with diabetic nephropathy

A patient with diabetic nephropathy who presented with multiple tender subcutaneous nodules caused by Mycobacterium marinum infection is presented.     

Early steroid withdrawal protocol with basiliximab, cyclosporine and mycophenolate mofetil in renal-transplant recipients

OBJECTIVE: Adverse effects of steroids have led to efforts to minimize their use in recipients of organ transplants. This study evaluated an early steroid withdrawal protocol including basiliximab, cyclosporine (CsA) and mycophenolate mofetil (MMF) in renal-transplant recipients. METHODS: Between January 2001 and April 2005, our early steroid withdrawal protocol was used in 130 patients who underwent renal transplantation. Immunosuppression consisted of CsA (6-8 mg/kg), MMF (2 g/kg) and methylprednisolone (MP); basiliximab was given as induction therapy (steroid withdrawal group). MP was administered in a dose of 500 mg or 250 mg at renal transplantation; thereafter, the dose was rapidly tapered and MP was withdrawn on day 14 post-transplant. RESULTS: The incidence of acute rejection in the steroid withdrawal group was similar to that in the conventional steroid treatment group (without basiliximab) (18% vs. 21%). The severity of rejection episodes was similar in the two groups. Patient and graft survivals were 100% and 97% in the steroid withdrawal group. In 80 of the 130 patients (62%) in the steroid withdrawal group, MP was successfully withdrawn, with good allograft function during follow-up. In the other 50 patients (38%), MP was reinitiated because of acute rejection or other reasons. The success rate of steroid withdrawal 12 months after transplantation in recipients of ABO-compatible grafts was significantly higher than that in recipients of ABO-incompatible grafts (66% vs. 44%). The dose of MMF during the 12 months after renal transplantation was significantly lower in steroid reinitiated group than in the successful withdrawn group (p<0.05). Patients in the successful withdrawn group showed metabolic benefits such as lower cholesterol levels as compared with the steroid reinitiated group. CONCLUSION: Although further follow-up is necessary to confirm our results, our protocol successfully permitted the early withdrawal of steroids in 62% of renal-transplant recipients, with no resumption of steroid treatment during 3 years of follow-up.