The changing role of the dental hygienist

This article describes the role of the dental hygienist in the Netherlands from the start of the training of dental hygienists in 1968. With the new Individual Health Care Professionals Bill from 1997 the dental hygienists are entitled to perform more tasks than in the past. This article describes the viewpoint of the professional dental hygienist organization on the future role of the dental hygienist. Cooperation with the other members of the dental team and free entry to the dental hygienist are considered important conditions. The creation of appropriate conditions by government and insurance companies is a matter of major concern.     

Closed suction drainage after knee arthroplasty. A prospective study of the effectiveness of the operation and of bacterial contamination

A prospective investigation was designed to determine the volume and the evolution of bleeding after closure of the surgical wound following knee arthroplasty, as well as the incidence of infection and bacterial contamination in relation with the time that the suction drain was left in place. The drain was removed either 12, 24 or 48 hours after the operation. The presence of any signs of clinical infection was recorded. The tip of the drain, 1 cm of its subcutaneous portion and a sample from the collecting bottle were studied for bacterial contamination. In the 12-hr group, no microorganisms were isolated in cultures either from the tip, the subcutaneous portion or the bottle of the drain. In the 24-hr group, 87% of the total postoperative bleeding was collected during the first 12 hours. In two cases, the samples obtained from the tip and the subcutaneous portion of the drain were positive for Staphylococcus epidermidis. In the 48-hr group, 91% and 97% of the total bleeding volume was collected during the first 12 and 24 hours, respectively. In two cases, St. epidermidis was isolated in cultures from the subcutaneous portion of the drain. The clinical evaluation of wound healing was comparable in all three groups.     

Anorectal malformations associated with enteric dysganglionosis in Danforth's short tail (Sd) mice

BACKGROUND: The spontaneous mutant Danforth's short tail (Sd) mouse has been studied over the last 60 years from the morphological, embryological, and genetic point of view. The Sd mutation affects a gene essential to notochordal development, and the Sd mouse phenotype represents an analogue of human caudal regression syndrome. The Sd/Sd mouse presents different types of anorectal malformations (ARM) and was suggested as a simple and cheap model of investigation of ARM morphology and embryology. In the current study, the Sd mouse enteric nervous system (ENS) was thoroughly investigated with specific immunohistochemical markers. METHODS: Macroscopic analysis, normal histology, and immunohistochemical techniques for detecting neurofilaments (NF) and NOS1 were used to study ENS of 138 Sd mice and 25 controls. RESULTS: The surprising results of this study showed that Sd mutation is associated with different degrees of hypoganglionosis and aganglionosis. In 41% of Sd/SD-affected mice, the rectal pouch was aganglionic and in the remaining 58% was severely hypoganglionic. In addition, 4.1% of heterozygous mice presented a distal aganglionosis and 8.3% hypoganglionosis. CONCLUSIONS: These results suggest that Sd mutation independently affects distinct cell lines during early organogenesis, as notochord cells, ventral hingut endoderm, and neuroblasts migrating from neural crest cells. Comparing the Sd murine model with human pathology, this study confirms that the association between ARM and intestinal dysganglionosis is not rare and underlines the importance of detecting in every ARM patient the innervation abnormalities of rectal pouch and fistulas.     

Negative sural nerve biopsy in neurolymphomatosis

Patients with non-Hodgkin’s lymphoma occasionally develop widespread invasion of peripheral nerves by tumor cells or neurolymphomatosis (NL). Clinically this usually results in asymmetrical, progressive, and painful polyneuropathy. Diagnosis rests on the identification of tumor cells in peripheral nerves. To avoid false-negative biopsy findings in patients with malignant lymphomatous infiltration of peripheral nerves it has been recommended to biopsy clinically involved nerves. We present two patients with histologically confirmed NL in whom sural the nerve biopsy finding was negative despite clinical and neurophysiological evidence of involvement of the sural nerve a. The clinical features of NL are reviewed. Some patients with neurolyphomatosis have only focal or proximal involvement of nerves, requiring the biopsy of an affected part of these nerves. Magnetic resonance imaging may be useful in identifying affected nerves. Received: 28 January 1999 Received in revised form: 7 July 1999 Accepted: 17 July 1999     

Correlation between angiotensin-converting enzyme gene insertion/deletion polymorphism and kidney graft long-term outcome in pediatric recipients: a single-center analysis

BACKGROUND: Despite numerous advances in the areas of organ preservation, histocompatibility, and immunosuppression, chronic deterioration of organ allograft function, referred to as "chronic rejection," still remains the main obstacle to long-term graft survival. The common feature of chronic rejection is a concentric generalized graft arteriosclerosis associated with interstitial fibrosis that reflects an allogeneic injury to graft arteries, possibly worsened by other alloantigen-independent risk factors. The presence of the angiotensin I-converting enzyme (ACE) gene-deleted (D) allele has been associated, when in homozygosity, with increased risk of cardiovascular diseases and with an accelerated progression of organ damage in a variety of kidney diseases. In this study, we analyzed whether the insertion/deletion polymorphism of the ACE gene, because of its negative prognostic impact on cardiovascular and renal pathology, could have any influence on kidney graft survival in pediatric recipients. METHODS: DNA was isolated from peripheral blood mononuclear cells from 146 pediatric dialysis patients (mean age: 12.9 years) who received a first kidney graft at our center between December 1985 and July 1997. To rule out any bias due to acute graft losses, only 119 patients who reached a minimum of 12 months of graft survival were considered for statistical analysis. The insertion/deletion polymorphism of the ACE gene was detected using a polymerase chain reaction technique with two flanking primers. RESULTS: The results demonstrated that (i) the distribution of DD and non-DD (ID + II) genotypes was 36.1% (43 patients) and 63.8% (76 patients), respectively; (ii) actuarial graft survival at 7, 8, 9, and 10 years in patients with non-DD genotype was significantly higher than that in patients with DD genotype (7 years: 94.6% vs. 72.4%, P<0.05; 8 years: 94.6% vs. 62%, P<0.025; 9 years: 87.3% vs. 51.4%, P<0.025; 10 years: 76.3% vs. 25.7%, P<0.01). CONCLUSIONS: In conclusion, the above data indicate that DD genotype is associated in pediatric kidney graft recipients with a shorter long-term kidney graft survival and suggest a possible role of this genotype as a cofactor in the progression of nonimmunological injuries leading to chronic kidney graft failure.     

Conventional CT signs in staging transitional cell tumors of the upper urinary tract

OBJECTIVES: To determine conventional computed tomography (CT) signs in the diagnosis and staging of upper urinary tract tumors (UUTTs). METHODS: Retrospective study was made of the CTs of 82 patients diagnosed with UUTTs. Nine CT signs were defined and compared with the pathology of the surgical specimen. A chi2 test was used for statistical analyses. RESULTS: We reviewed the CTs of 93 UUTTs in 82 patients, of which 36% were invasive and 12% had positive lymph nodes. Renal parenchymal invasion was found in 82% of high-grade and in 18% of low-grade tumors (p = 0.001). 94% of the tumors with signs of renal parenchymal invasion were invasive (p < 0.001), as well as 88% of those appearing as renal masses (p = 0.005), with a global sensitivity of 64% and specificity of 97%. The CT sensitivity and specificity of detecting infiltration of the ureter was 67 and 77%, respectively, and no sign was statistically significant. The detection of lymph node involvement had a sensitivity of 87.5% and a specificity of 98%. CONCLUSIONS: CT offers good sensitivity (87.5%) and specificity (98%) in the detection of lymph node involvement, and 64% sensitivity and 97% specificity for the detection of renal tumor invasion.