Bioactive glass enhances bone ingrowth into the porous titanium coating on orthopaedic implants

Purpose

The aim of the study was to verify the ability of nanoparticulate bioactive glass (BAG) to infiltrate into the porous titanium (Ti) layer on Ti-based implants to promote osseointegration.

Methods

The porous titanium layer on Ti-based implants was impregnated with nanoparticulate BAG. The implants without or with BAG were implanted bilaterally in tibial holes of ten New Zealand white rabbits. The rabbits were sacrificed after ten weeks for examinations. Beside histological examination, EDXS analysis of polished cross-sections of explanted implants was also performed with the aim to quantitatively evaluate the bone-to-pore contact and bone-in-pore ratio.

Results

After ten weeks, EDXS analyses of cross-sections of the explanted implants confirmed that bioactive glass was fully resorbed and that the pores throughout the thickness of the porous titanium layer were to a large extent filled with a new bone. In the absence of bioactive glass, only the outer part of the porous layer was filled with bone. The implants without BAG in the porous Ti-layer exhibited similar bone-to-pore contact, while significant improvement of bone ingrowth into the pores was observed for the implants with BAG (38%), as opposed to those without it (22%).

Conclusion

This study confirmed that the nanoparticulate bioactive glass within the porous titanium surface layer on implants promotes osseointegration and stimulates the formation of bone within the pores.     

Aberrant IgA1 glycosylation is inherited in familial and sporadic IgA nephropathy

IgA nephropathy (IgAN) is a complex trait determined by genetic and environmental factors. Most IgAN patients exhibit a characteristic undergalactosylation of the O-glycans of the IgA1 hinge region, which promotes formation and glomerular deposition of immune complexes. It is not known whether this aberrant glycosylation is the result of an acquired or inherited defect, or whether the presence of aberrant IgA1 glycoforms alone can produce IgAN. A newly validated lectin enzyme-linked immunosorbent assay (ELISA) was used to determine the serum level of galactose-deficient IgA1 (Gd-IgA1) in a cohort of 89 IgAN patients and 266 of their relatives. High Gd-IgA1 levels (> or =95th percentile for controls) were observed in all 5 available patients with familial IgAN, in 21 of 45 (47%) of their at-risk relatives (assuming autosomal dominant inheritance), and in only 1 of 19 (5%) of unrelated individuals who married into the family. This provides evidence that abnormal IgA1 glycosylation is an inherited rather than acquired trait. Similarly, Gd-IgA1 levels were high in 65 of 84 (78%) patients with sporadic IgAN and in 50 of 202 (25%) blood relatives. Heritability of Gd-IgA1 was estimated at 0.54 (P = 0.0001), and segregation analysis suggested the presence of a major dominant gene on a polygenic background. Because most relatives with abnormal IgA1 glycoforms were asymptomatic, additional cofactors must be required for IgAN to develop. The fact that abnormal IgA1 glycosylation clusters in most but not all families suggests that measuring Gd-IgA1 may help distinguish patients with different pathogenic mechanisms of disease.     

Sleep disorders and quality of life in renal transplant recipients

Kidney transplantation provides the best outcome for patients with end-stage renal failure both in terms of morbidity and mortality and health-related quality of life (QoL). Health-related QoL has become recognized as an important outcome measure in patients with different chronic medical conditions, including chronic kidney disease (CKD). There are several factors in kidney-transplanted patients which have a negative impact on QoL in these patients. Sleep disorders, such as insomnia, sleep apnea syndrome (SAS), and restless legs syndrome (RLS), are common in kidney-transplanted patients and clearly belong to this group of factors, although there is only limited published data available about the association between sleep problems and QoL in this patient population. The prevalence of both insomnia and RLS is reduced in kidney-transplanted patients compared to dialysis patients, and it is similar to the prevalence observed in the general population. The prevalence of sleep apnea, however, is very high, around 30%. The association between the presence of these sleep disorders and impaired QoL has been relatively well documented in dialysis patients, but there is only scarce published information about this association in the kidney transplant population. In this paper, we will summarize data from the literature describing the impact of sleep problems, which are potentially treatable, on QoL in kidney-transplanted patients. We suggest that the appropriate diagnosis and management of sleep disorders may improve QoL in kidney-transplanted patients.     

Selection of Operative Procedures for Cubital Tunnel Syndrome

The purpose of this study was to investigate the primary operative procedures that are performed by hand surgeons for cubital tunnel syndrome and their reported satisfaction with these procedures. The survey consisted of 22 questions regarding primary operative treatment of cubital tunnel syndrome and demographics and was sent by email to the 459 active members of the American Association for Hand Surgery. One hundred sixty-four surgeons completed the survey (36% response rate). The total sample included 154 hand surgeons (143 males, 11 females) who operated on cubital tunnel syndrome and the majority of surgeons were in private practice (n = 100) followed by academic practice (n = 50). The most prevalent factors that influence the decision to operate include evidence of muscle atrophy (84%), abnormal nerve conduction studies (51%), and failed non-operative treatment (49%). Most surgeons (n = 133) reported using more than one operative procedure for their patients with cubital tunnel syndrome. Factors that influenced the operative procedure selected included the degree of nerve compression (60%), medical comorbidities (30%), patient's occupation (28%), and obesity (22%). Following carpal tunnel surgery, 88% of the surgeons were "very satisfied" with their patient outcome and following surgery for cubital tunnel syndrome, only 44% were "very satisfied" with their patient outcome. Most surgeons use more than one operative procedure in their treatment of patients with cubital tunnel syndrome and the selection of the operative procedure is influenced by patient factors and surgeon preference.     

IgA1-containing immune complexes in IgA nephropathy differentially affect proliferation of mesangial cells

BACKGROUND: Sera of patients with IgA nephropathy (IgAN) contain circulating immune complexes (CIC) composed of galactose-deficient IgA1 complexed with antiglycan antibodies. The role of these CIC in the pathogenesis of IgAN is not known. METHODS: We studied how proliferation of cultured mesangial cells (MC) is affected by CIC prepared from sera of IgAN patients and healthy control subjects using size-exclusion chromatography. CIC-containing fractions were added to serum-starved MC in culture, and cell proliferation was measured using (3)H-thymidine incorporation. The results were confirmed by staining MC using an antibody against proliferating cell nuclear antigen. RESULTS: The incubation of starved MC with serum fractions with M(r) 800 to 900 kD, rich with galactose-deficient IgA1, stimulated proliferation, while fractions with smaller complexes were inhibitory. Furthermore, CIC-containing larger molecular mass fractions isolated from serum of an IgAN patient collected during an episode of macroscopic hematuria stimulated MC proliferation more than CIC obtained during a subsequent quiescent phase. To examine the role of IgA, we removed IgA1 from serum before fractionation. The resultant IgA1-depleted fractions were devoid of stimulatory IgA-CIC. Sera of IgAN patients were also fractionated after addition of desialylated galactose-deficient polymeric IgA1 to form additional immune complexes. Supplementation with a small quantity of this IgA1 increased cellular proliferation in assays using serum fractions of M(r)>/=800 to 900 kD; uncomplexed IgA1 did not affect MC proliferation significantly. In contrast, supplementation with a larger quantity of this IgA1 inhibited cellular proliferation in assays using serum fractions of M(r) 700 to 800 kD. CONCLUSION: Overall, these findings suggest that CIC containing aberrantly glycosylated IgA1 affect proliferation of MC in vitro and, thus, likely play a role in the pathogenesis of IgAN.     

Ichthyosis associated with widespread tinea corporis: report of three cases

Ichthyoses are a common group of keratinization disorders. A non-inflammatorygeneralized persistent skin desquamation is observed. It is characterized byincreased cell turnover, thickening of the stratum corneum and functional changes ofsebaceous and sweat glands. All of these favor fungal proliferation. Dermatophytesmay infect skin, hair and nails causing ringworm or tinea. They have the ability toobtain nutrients from keratinized material. One of its most prevalent genera isTrichophyton rubrum. Although tineas and ichthyoses are quite common, the associationof the two entities is rarely reported in the literature. Three cases of ichthyosisassociated with widespread infection by T. rubrum are presented. Resistance toseveral antifungal treatments was responsible for worsening of ichthyosis signs andsymptoms.     

Long-term results after surgical basal cell carcinoma excision in the eyelid region

AIMS: To evaluate the data for patients with basal cell carcinoma (BCC) in the eyelid region, to demonstrate histologically controlled tumour excision, and to prove the efficacy of the treatment on the basis of long term observations. METHODS: Retrospective analysis of 382 microscopically controlled BCC excisions in the eyelid apparatus (350 patients) in a follow up study over 5.7 (SD 1.1) years. Tumour location, tumour size, and histological results were recorded. The same procedure was followed for recurrences. Follow up examinations were carried out 1, 3, 6, and 12 months after the operation, and then annually for a further 4 years or longer. RESULTS: A recurrence rate of 5.36% was observed after the primary operation. 60.3% of first recurrences occurred in the medial canthus, 41.2% showed in depth extension, and sclerosing types were overly represented at 35.3%. After the second operation the recurrence rate increased to 14.7% and reached 50% after a third and fourth operation. CONCLUSIONS: The greatest risk of recurrence exists for BCCs of the medial canthus with in depth extension, and for sclerosing types. The recurrence rate increases after every operation. For high risk cases, consideration should be given to adjuvant treatment such as radiotherapy.