Subcellular distribution and relative expression of fibrocyte markers in the CD/1 mouse cochlea assessed by semiquantitative immunogold electron microscopy

Spiral ligament fibrocytes function in cochlear homeostasis, maintaining the endocochlear potential by participating in potassium recycling, and fibrocyte degeneration contributes to hearing loss. Their superficial location makes them amenable to replacement by cellular transplantation. Fibrocyte cultures offer one source of transplantable cells, but determining what fibrocyte types they contain and what phenotype transplanted cells may adopt is problematic. Here, we use immunogold electron microscopy to assess the relative expression of markers in native fibrocytes of the CD/1 mouse spiral ligament. Caldesmon and aquaporin 1 are expressed more in type III fibrocytes than any other type. S-100 is strongly expressed in types I, II, and V fibrocytes, and α1Na,K-ATPase is expressed strongly only in types II and V. By combining caldesmon or aquaporin 1 with S-100 and α1Na,K-ATPase, a ratiometric analysis of immunogold density distinguishes all except type II and type V fibrocytes. Other putative markers (creatine kinase BB and connective tissue growth factor) did not provide additional useful analytical attributes. By labeling serial sections or by double or triple labeling with combinations of three antibodies, this technique could be used to distinguish all except type II and type V fibrocytes in culture or after cellular transplantation into the lateral wall.

Inequalities in glycaemic control in patients with Type 2 diabetes in primary care

AIMS

To quantify relationships between patient and practice factors and glycaemic control in patients with Type 2 diabetes.

METHODS

A cross-sectional study involving 1534 patients with Type 2 diabetes from 42 general practices in Nottingham, UK was undertaken. Patient characteristics were assessed by a clinical interview and case note review and practice characteristics by a questionnaire. The outcome measure was serum HbA(1c) concentration measured at entry to the study. Random effects linear regression was used to model patient and practice factors associated with glycaemic control.

RESULTS

In multivariable regression analysis, HbA(1c) increased with increasing body mass index (BMI) [change in HbA(1c) for one unit increase in BMI: 0.03%, 95% confidence interval (CI) 0.01, 0.04], and was higher in those using oral medication (mean difference 0.75%, 95% CI 0.59, 0.92) or insulin compared with diet (mean difference 1.36%, 95% CI 1.10, 1.62). There was a dose-response relationship between HbA(1c) and increasing time since diagnosis. HbA(1c) was negatively associated with age (change per year -0.01%, 95% CI -0.02, -0.004). Patients registered at the most deprived practices had higher HbA(1c) values than those in the least deprived practices (mean difference 0.42%, 95% CI 0.14, 0.71), as did those in practices where annual reviews were carried out by the nurse alone (mean difference 0.24%, 95% CI 0.04, 0.44).

CONCLUSIONS

Several patient and practice factors are related to glycaemic control. Poorer glycaemic control was associated with practice level deprivation and nurses undertaking annual reviews alone. Further research is required to explore outcomes of annual reviews undertaken by nurses alone. Greater resources may be needed by primary care teams working in deprived areas to address inequalities in diabetic control.