Biomedical subjects

H K Wolf

Publications and source records attributed to H K Wolf.

At least 19 recordsLinked to original sources

PubMed2004

[Identification of pelvic autonomic nerves during partial and total mesorectal excision--influence parameters and significance for neurogenic bladder].

INTRODUCTION: The objective of the present prospective study was to determine the frequency of pelvic autonomic nerve preservation (PANP) during total mesorectal excision (TME) for rectal carcinoma, and to identify a possible link between PANP and postoperative micturition disturbances. METHODS: Between March 1997 and February 2003, 229 patients with adenocarcinoma of the rectum were operated on with sphincter preservation in 178 (78%) cases. In 101 (48%) patients, the tumor did not invade the muscularis propria. To determine influence parameters on the achievement of complete PANP, a multivariate analysis was performed. The number of complete-partial-or nonidentification of the nerves (superior hypogastric plexus up to the neurovascular bundles) was documented and correlated with micturition disturbances. RESULTS: The pelvic autonomic nerves were identified completely in 169 (74%), partially in 25 (11%), and could not be demonstrated in 35 (15%) patients. Multivariate analysis showed multivisceral resection ( p<0.001), gender ( p<0.001), surgeon (<25 operations >, p<0.001), and tumor site (middle/upper third vs lower third of rectum, p= 0.011) to exert an independent influence on the achievement of complete PANP. Twenty (8.8%) patients needed a long-term urinary catheter. Preservation of the parasympathetic nerves was associated with low bladder dysfunction rates (4.1 vs 22.4%, p<0.001). CONCLUSIONS: To minimize the risk of postoperative micturition disturbances due to neurogenic bladder, pelvic autonomic nerves should be identified during TME. Neurogenic bladder after TME is a useful parameter to assess the quality of surgical treatment for rectal carcinoma.

Adult↗

PubMed2004

Extended radical lymphadenectomy in patients with urothelial bladder cancer: results of a prospective multicenter study.

PURPOSE: Previous studies demonstrate a positive correlation between postoperative survival and the extent of pelvic lymphadenectomies in patients with bladder cancer. However, the distribution of nodal metastases has not been examined in sufficient detail. Therefore, we conducted a comprehensive prospective analysis of lymph node metastases to obtain precise knowledge about the pattern of lymphatic tumor spread. MATERIALS AND METHODS: Between 1999 and 2002 we performed 290 radical cystectomies and extended lymphadenectomies. Cranial border of the lymphadenectomy was the level of the inferior mesenteric artery, lateral border was the genitofemoral nerve and caudal border was the pelvic floor. We made every effort to excise and examine microscopically all lymph nodes from 12 well-defined anatomical locations. RESULTS: Mean total number and standard deviation of lymph nodes removed was 43.1 +/- 16.1. Nodal metastases were present in 27.9% of patients. The percentage of metastases at different sites ranged from 14.1% (right obturator nodes) to 2.9% (right paracaval nodes above the aortic bifurcation). By studying cases of unilateral primary tumors or with only 1 metastasis we observed a preferred pattern of metastatic spread. However, there were many exceptions to the rule and we did not identify a well-defined sentinel lymph node. CONCLUSIONS: We strongly recommend extended radical lymphadenectomy to all patients undergoing radical cystectomy for bladder cancer to remove all metastatic tumor deposits completely. The operation can be conducted in routine clinical practice and our data may serve as a guideline for future standardization and quality control of the procedure.

Adult↗

PubMed2003

[Total excision of the mesorectum in cancer of the lower and middle rectum. Oncological and functional results].

INTRODUCTION: The introduction of total mesorectal excision (TME) in the treatment of rectal cancer has improved survival rates and decreased recurrence. Our objective was to analyse perioperative data as well as the results of the follow-up examination. Risk-factors for local recurrence should be identified since the indication for adjuvant therapy in "optimal surgery" has to be redefined. PATIENTS AND METHODS: Between March 1997 and December 2001, 108 patients with adenocarcinoma of the lower and middle rectum were operated on by three surgeons according to the concept of total mesorectal excision. In 75 (69.4%) patients,a lower anterior resection and in 32 (29.2%) cases an abdominoperineal resection was performed. One patient received a Hartmann's resection. There were 15 cases of stage IV (UICC) present and in 53 patients the tumor extension was restricted to the wall. Demographic and perioperative data as well as the results of the follow-up examination were registered prospectively. The median follow-up period amounted to 24 months (2-56). RESULTS: A total of 87 patients underwent a curative resection. Fourteen lymph nodes were dissected (median). Pelvic autonomic nerve preservation was possible in 90 patients. The median intraoperative blood loss was 500 ml. As surgical complications, anastomotic leakage occurred in 18% of cases, perineal wound infection in 33%, and bladder dysfunction (requiring catheterisation) in 5.6%. The overall rate of recurrence was 17.5%. The rate of local recurrence was 4.9% and the survival rate was 91% over 3 years. Risk factors for local recurrence are N2-disease, transmural growth and tumor localisation in the lower third of the rectum. CONCLUSIONS: TME offers good oncological and functional results with low complication rates for the treatment of cancer in the middle and upper third of the rectum. Interdisciplinary multicenter studies are still necessary to redefine the place of adjuvant radiation and chemotherapy in cases of cancer in the lower two thirds of the rectum and stage III disease.

Adenocarcinoma↗

PubMed2003

[Ranking of pelvic lymphadenectomy in therapy and prognosis of carcinoma of the bladder].

PURPOSE: Due to the absence of internationally recognised guidelines on the necessary extent of lymphatic node removal in carcinoma of the bladder, we are still not sure as to which procedure is most favourable to therapeutic success. Hence, we checked retrospectively on the influence exercised by radical surgery on prognosis. MATERIAL AND METHOD: 506 patients were analysed retrospectively after radical cystectomy and pelvic lymphadenectomy with regard to the influence exercised on prognosis by clinical and histopathological variables. RESULTS: Statistically significant influential factors in univariate analysis were in the retrospective examination: the pT category (p < 0.0001), lymphatic node status (p < 0.0001), grading (p = 0.0145), proof of uronephrosis (p = 0.0007), number of performed transurethral resections (p = 0.0043), surgeon (p = 0.0033) and number of resected lymph nodes (p = 0.0012). There was a significant difference between surgeons at a median number of 14.3 removed lymphatic nodes (range 1 - 46) in respect of radicality (p = 0.001) and prognosis (p < 0.0049). Independent influential factors in multivariate analysis were: pT category (p = 0.003), pN category (p < 0.001) and the number of surgically removed lymphatic nodes (p = 0.038). CONCLUSION: In our retrospectively examined group of patients extensive lymphadenectomy significantly improved the prognosis and was thus a potentially curative procedure. Basing on these results, prospective studies will have to clarify the level of the standard applicable to pelvic lymphadenectomy and also the advantages and prospects of radical surgery in respect of possible patient survival.

Adult↗

PubMed2002

[Significance of pelvic lymphadenectomy for the prognosis after radical cystectomy].

OBJECTIVE: In contrast to other carcinomas such as breast or colon cancer, there are no guidelines regarding the number and location of lymph nodes to be removed during radical surgery in patients with invasive bladder carcinoma. The therapeutic effect of pelvic lymphadenectomy and its influence on tumour staging has not been documented yet. METHODS: Here we present an evaluation of pelvic lymph nodes from 484 patients who underwent radical cystectomy with curative intention between 1986 and 1999. The number of lymph nodes was correlated with the depth of invasion of the primary tumour, occurrence of nodal metastases, clinical outcome, the operating surgeon, and the pathologist. RESULTS: There were 484 patients with a mean age of 62.7 years. Clinical follow up was available from 321 patients with a mean follow up period of 35.9 months. The average number of lymph nodes removed was 14.3 (range: 1-46). The number of lymph nodes removed varied significantly between different surgeons and did not correlate with the pathologists. There was a significant correlation between the number of lymph nodes removed and the tumour-free survival in pT2 or pT3 tumours and in patients without lymph node metastases. Multivariate analysis revealed that pT-category (p < 0.01), pN-category (p < 0.01), and the total number of lymph nodes removed (p = 0.04) were the most important factors affecting survival. CONCLUSION: The more extensive lymphadenectomy significantly improved the prognosis of patients with invasive bladder cancer and therefore, represents a potentially curative procedure. The results indicate a need for a standardised lymph node dissection.

Adult↗

PubMed2001

Expression of thrombospondin-1 in pancreatic carcinoma: correlation with microvessel density.

Thrombospondin-1 (TSP-1) is a multifunctional platelet and extracellular matrix protein that is involved in angiogenesis. Under certain pathological conditions, e.g., malignant tumors, high concentrations of TSP-1 work as an angiogenic agonist. Here we examined 98 pancreatic carcinomas with respect to TSP-1 immunoreactivity and its correlation to intratumoral microvessel density (MVD), a representation of the overall degree of angiogenesis in carcinomas. Northern blot analysis for TSP-1 mRNA was performed in seven additional cases. Eighty-seven tumors showed strong TSP-1 immunoreactivity, nine carcinomas were only weakly positive, and two lesions were negative for TSP-1. TSP-1 immunoreactivity was detected in the extracellular matrix, mostly at the invasion front of the tumor. Using Northern blot analysis, we observed high levels of TSP-1 mRNA in three out of seven pancreatic carcinomas. The mean MVD in pancreatic carcinoma was 38.8 vessels per mm2. Tumors with a high expression of TSP-1 showed a higher MVD and the correlation between TSP-1 immunoreactivity and microvessel density was highly significant (P=0.003). As a modulator of angiogenesis, TSP-1 is strongly expressed in most pancreatic adenocarcinomas and is likely to contribute to the extensive neovascularization and spread of this highly aggressive tumor.

Adenocarcinoma↗

PubMed2001

[Hereditary pancreatitis - a clinically relevant cause of pancreatic adenocarcinoma?].

UNLABELLED: Hereditary pancreatitis is an autosomal dominant disease. Recently, the genetic defect has been mapped to chromosome 7q35 and consists mainly of a point mutation in exon 3 of the cationic trypsinogen gene which causes an Arg(CGC)-His(CAC) substitution at residue 117. In patients with hereditary pancreatitis the estimated cumulative risk for pancreatic carcinoma to age 70 approaches 40 %. Thus, the role of hereditary pancreatitis in the pathogenesis of pancreatic carcinoma is of interest. PATIENTS AND METHODS: DNA was extracted from peripheral blood (n = 16), fresh tumor tissue (n = 29) and formalin fixed and paraffin embedded tumor tissue (n = 5) of 50 patients with ductal adenocarcinoma of the pancreas. We specifically amplified exon 3 and the intronic flanking sequences of the cationic trypsinogen gene by nested PCR and performed restriction fragment length polymorphism analysis using the restriction enzyme Afl III. In patients with hereditary pancreatitis the G : A point mutation creates a recognition site for Afl III which is not present in unaffected individuals. RESULTS: None of the 50 patients with ductal adenocarcinoma of the pancreas revealed the G : A point mutation in exon 3 of the cationic trypsinogen gene which is characteristic of hereditary pancreatitis. In addition sequencing of exon 3 did not reveal any other mutations in the DNA of patients with pancreatic adenocarcinoma. CONCLUSION: Although hereditary pancreatitis markedly increases the risk for pancreatic cancer, it is rare and probably of little significance with respect to the pathogenesis of the majority of pancreatic adenocarcinomas.

Adenocarcinoma↗

PubMed2001

Prognostic significance of histopathological grading and immunoreactivity for p53 and p21/WAF1 in grade 2 pTa transitional cell carcinoma of the urinary bladder.

OBJECTIVE: At present, there are no predictors of tumour behaviour for grade (G) 2 pTa transitional cell carcinomas (TCC) of the bladder. Here we analyse the prognostic relevance of histopathological grading and the immunohistochemical detection of p53 and p21/WAF1. METHODS: 70 patients were newly diagnosed with G2 pTa TCC of the bladder based on transurethral resection specimens. Two pathologists, blinded with respect to the clinical outcome, confirmed the initial grade and subclassified the G2 lesions into G2a and G2b carcinomas based on the degree of nuclear atypia and the number of mitoses. Immunoreactivity for p53 and p21/WAF1 was evaluated semiquantitatively. RESULTS: There were 52 G2a and 18 G2b tumours, mean follow-up was 49.2 months. Of all patients, 31.4% remained tumour-free, 48.6% recurred with the same tumour grade and stage, and 20.0% showed tumour progression. Patients with G2a tumours developed tumour progression in 13% in contrast to 39% with G2b lesions (p = 0.037). Of 21 p53-positive tumours, 33% (7/21) developed progressive disease, whereas 14% (7/49) of p53-negative patients showed tumour progression (p = 0.102). Neither p21/WAF1 expression alone nor the combination of p53 and p21/WAF1 correlated with clinical outcome. CONCLUSION: The more detailed grading system but not p53 or p21/WAF1 immunohistochemistry was found to be an independent prognostic factor for tumour progression.

Carcinoma, Transitional Cell↗

PubMed2000

[Budd-Chiari syndrome--a rare manifestation of hereditary thrombophilia].

Budd-Chiari syndrome is a rare manifestation of hereditary or acquired thrombophilia. We saw a case of Budd-Chiari syndrome in a 30-year-old woman leading to initial diagnostic difficulties. She underwent surgical side-to-side shunt and 9 weeks later an almost normal liver could be demonstrated on computerized tomography. Budd-Chiari syndrome should be considered if the Chiari triad with abdominal pain, hepatomegaly and ascites occurs in a patient. If necessary, invasive diagnostic procedures (e.g. angiography) must be performed. Therapeutic options are anticoagulative therapy and porto-systemic shunt, either as a TIPS or a surgical shunt. If severe liver failure occurs or liver cirrhosis is present, orthotopic liver transplantation is an additional option which also cures hereditary thrombophilia.

Activated Protein C Resistance↗

PubMed2000

[Adenocarcinoma in a tail-gut cyst: a rare cause of recurrent perianal fistula].

A 58-year-old woman was initially externally diagnosed in 1983 with a presacral mass, which was subsequently treated as an abscess. Thereafter, the patient experienced recurrent perianal fistulas. Further diagnostic studies revealed a cystic tumor, considered to be an epidermoid cyst, which was located in the inferior pelvis and was consequently removed. Histologically, cystic scar tissue was found with a highly differentiated adenocarcinoma which measured 4 cm. Later on, the patient again experienced perianal fistulas originating from a renewed presacral mass. As a result, an abdominal-perianal rectum extirpation and a partial resection of the sacrum with placement of a descendostomy were done. Histologically, adenocarcinoma tissue was found at the base of a tail-gut cyst. One year following her operation, the patient is free from any complaints and relapses. The tail-gut cyst is a very rare entity which arises from the inadequate involution of the tail-gut during embryonal development. A malignant transformation occurs in 10% of the cases. In the case of recurrent perianal fistulas and cystic masses between the rectum and os sacrum or os coccygeum, a tail-gut cyst should be taken into consideration, the goal being its complete removal.

Adenocarcinoma↗

PubMed2000

p53 immunoreactivity in biopsy specimens of T1G3 transitional cell carcinoma of the bladder--a helpful parameter in guiding the decision for or against cystectomy?

The aim of this study was to determine whether p53 is helpful in making the decision to undergo cystectomy in T1, G3 transitional cell carcinoma (TCC) of the bladder, by prospectively comparing the p53 status of bladder biopsies with the histology and p53 status of the corresponding cystectomy specimens. From January 1996 to August 1997, 38 consecutive patients with T1G3 TCC at 6 different centres were enrolled into the study. Bladder biopsies and cystectomy specimens were examined with three different antibodies against p53. The p53 status of each bladder biopsy was compared with p53 status, tumour stage and grade of the cystectomy specimen. An independent evaluation of the histology and immunohistochemistry was carried out by two pathologists. 15 of 38 patients (39%) were found to have a higher tumour stage in the cystectomy specimen compared with the staging by transurethral resection of the bladder tumour (TUR-B). 3 patients did not show residual tumour in the cystectomy specimen. No differences in p53 positivity were noted between the different antibodies. 14 of 31 evaluable tumours (45%) were p53 positive at the time of the TUR-B. p53 staining of the TUR-B specimen did not correctly predict the residual tumour in the cystectomy specimen. We, therefore, concluded that compared with standard histopathology, the p53 status of the TUR-B specimen does not provide additional relevant information with regard to local tumour staging and, thus, is not helpful in making the decision for or against a cystectomy.

Adult↗

PubMed2000

Lymphadenectomy in patients with transitional cell carcinoma of the urinary bladder; significance for staging and prognosis.

OBJECTIVE: To determine the need to standardize the number and location of lymph nodes to be removed during radical cystectomy in patients with invasive bladder carcinoma. PATIENTS AND METHODS: The pelvic lymph nodes from 447 patients (mean age 62.8 years) who underwent radical cystectomy between 1986 and 1997 were evaluated. The number of lymph nodes was correlated with the depth of invasion of the primary tumour (pT), occurrence of nodal metastases, clinical outcome, the operating surgeons and the pathologists dissecting the nodes. RESULTS: The clinical follow-up was available for 302 patients (mean follow-up 38.7 months). The mean (range) number of lymph nodes removed was 14.7 (1-46). The number of lymph nodes removed varied significantly among different surgeons but not among pathologists. In pT3 and pT4 tumours, a more extended lymphadenectomy (>/= 16 lymph nodes) correlated with a higher percentage of patients with documented nodal metastases. There was a significant correlation between the number of lymph nodes removed and the tumour-free 5-year survival in patients with pT1, pT2 or pT3 tumours, and in patients with 1-5 positive lymph nodes (P < 0.01). CONCLUSION: Extensive lymphadenectomy significantly improves the prognosis of patients with invasive bladder cancer and represents a potentially curative procedure in patients with nodal metastases, including micrometastases that may escape detection during routine histopathological evaluation. The results indicate the need for a standardized lymph node dissection.

Carcinoma, Transitional Cell↗

PubMed2000

Subregional pathology of the amygdala complex and entorhinal region in surgical specimens from patients with pharmacoresistant temporal lobe epilepsy.

The hippocampus, amygdala complex, and entorhinal region represent anatomically linked limbic structures of the mesiotemporal lobe. Chronic seizures and mnestic deficits in patients with pharmacoresistant mesial temporal lobe epilepsy (TLE) appear to correlate with distinct patterns of histopathological alterations in these areas. The complex anatomical organization of the amygdala and entorhinal region, however, render a detailed neuropathological evaluation of surgical specimens difficult. In this study, we present a combined cytoarchitectonical, pigmentarchitectonical, myelinarchitectonical, and immunohistochemical reconstruction of the amygdala, entorhinal region, and hippocampus from surgical TLE specimens (n = 20) in order to analyze their regional and cellular patterns of pathology. Anterior mesiotemporal lobes dissected in different spatial planes were obtained from 4 autopsy control patients and used for the characterization of neuroanatomical landmarks. Lateral, basal, and granular subnuclei of the amygdala were consistently identified in the surgical specimens. Major histopathological alterations included neuronal cell loss as revealed by extracellular lipofuscin accumulation, glial satellitosis, as well as cellular and fibrillary gliosis. The regional distribution of neuropathological changes varied considerably between different subnuclei but the lateral nucleus was more often involved than basal and granular nuclei. These amygdala nuclei appeared to be more severely affected compared to the adjacent entorhinal region. In addition, patients presenting with secondary generalized tonic-clonic seizures showed significantly more damage in mesiotemporal structures. Pathological alterations in the amygdala and entorhinal region were found to be associated with Ammon's horn sclerosis in most but not all cases. Our findings reveal the amygdala as a major target for epilepsy-associated neuronal cell damage. Significant variations in the lesional pattern among patients with chronic TLE would also be compatible with different spreading pathways of epileptogenic activity within the mesial temporal lobe.

Adolescent↗

PubMed2000

Trends in the incidence of acute myocardial infarction between 1984 and 1993 - The Halifax County MONICA Project.

BACKGROUND: According to vital statistics data for Halifax County, between 1984 and 1993 the annual mortality rate decreased for ischemic heart disease and myocardial infarction (MI). OBJECTIVES: To estimate the change in MI mortality, applying standardized diagnostic criteria; to determine whether decreased case fatality or decreased MI event rate, or both, caused decreased mortality; and to determine the contribution of MI incidence rate to altered event rate. PATIENTS AND METHODS: All persons in the study area aged 25 to 74 years and admitted to hospital or dying outside hospital with suspected acute coronary syndromes were registered prospectively. Demographic, health history and clinical data were extracted from medical records or collected from medical examiner reports, next-of-kin interviews or family physicians. Definite or possible MI was diagnosed according to World Health Organization MONItoring of trends and determinants in CArdiovascular disease (MONICA) criteria. Trends in age- and sex-standardized rates were estimated by using log-linear regression analysis. RESULTS: Of 4283 patients admitted to hospital for MI, 23.9% died within 28 days; 1401 patients who had suffered an MI died before admission to hospital. MI mortality decreased annually by 3.9% (95% CI 1.9 to 5.8); two-thirds of the decline was due to MI event rates (2.6%; CI 1.3 to 3.8) and one-third to a decrease in 28-day case fatality (1.3%; CI 0.2 to 2. 3). A decrease in MI incidence rate (3.2%; CI 1.7 to 4.8), rather than a decline in MI recurrence rate (1.4%; CI 0.7 to -3.5), was the major reason for the declining event rate. CONCLUSIONS: A decrease in the incidence of MI, possibly due to primary prevention, had a major impact on the declining MI mortality. Decreased in-hospital MI fatality, possibly due to improved treatment, was responsible for the decline in case fatality.

Adult↗

PubMed2000

Trends in the in-hospital treatment of acute myocardial infarction between 1984 and 1993 - The Halifax County MONICA Project.

BACKGROUND: The Halifax County MONItoring of trends and determinants in CArdiovascular disease (MONICA) Project found that between 1984 and 1988, the proportion of myocardial infarctions (MIs) that were fatal within 28 days remained constant, but declined between 1989 and 1993. The objective was to investigate association among case fatality, treatment and case severity of MI in hospitalized patients. PATIENTS AND METHODS: The MONICA MI register contains data on demographics, health history, in-hospital investigations, interventions and treatment, and vital status at 28 days after onset of symptoms for all MIs occurring in residents of Halifax County, aged 25 to 74 years. Logistic regression analysis was used to estimate trends in the use of cardioactive drugs and revascularization procedures. A case severity score was developed from patient characteristics at time of admission. Case fatality was calculated as the proportion of MIs that were fatal within 28 days. RESULTS: Between 1984 and 1988, a large increase (OR 1.3) occurred in the use of angiotensin-converting enzyme (ACE) inhibitors, acetylsalicylic acid (ASA), thrombolysis and percutaneous transluminal coronary angioplasty (PTCA); a minor increase occurred in use of calcium channel blockers (OR=1.29, 99% CI 1.19 to 1.40); beta-blocker use decreased; case fatality remained constant and case severity score increased. From 1989 to 1993, ACE inhibitor use increased (OR=1.4, 99% CI 1.27 to 1.55); minor increases occurred in use of ASA and beta-blockers, and in PTCA and coronary artery bypass grafting; case severity did not change and case fatality decreased. CONCLUSIONS: While use of beneficial treatment increased between 1984 and 1988, MI case fatality did not decrease, probably because case severity increased. Between 1989 and 1993, case severity remained constant, and the further increase in the use of beneficial therapy was associated with a decline in case fatality.

Acute Disease↗

PubMed1999

Trends in the prevalence and treatment of hypertension in Halifax County from 1985 to 1995.

BACKGROUND: The objective of this study was to document changes in the prevalence and treatment of hypertension in Halifax County from 1985 to 1995 in an effort to observe, at the population level, the consequences of the availability of new antihypertensive medications. METHODS: The study population comprised a random sample of Halifax County residents, aged 25-64 years, who responded to the 1985 and 1995 surveys of the Halifax County MONICA Project and residents who responded to the Nova Scotia Health Survey conducted in 1995. Data from the two 1995 surveys were pooled. Information on hypertension awareness and use of medication were obtained through questionnaires, and blood pressure was measured according to a standard protocol, using phase I and V of Korotkoff sounds as respective markers for systolic and diastolic pressures. Uncontrolled hypertension was defined as a systolic pressure of 140 mm Hg or greater and a diastolic pressure of 90 mm Hg or greater. Changes in the prevalence of hypertension, prescribing trends and medication costs were examined, and the association between the type of antihypertensive treatment and characteristics of the respondents with self-reported hypertension was investigated by multivariate logistic regression. RESULTS: Of the 917 people interviewed in 1985 and the 1338 in 1995, 274 (29.9%) and 356 (26.6%), respectively, reported a history of hypertension. When age was controlled for, the proportion of respondents reporting hypertension did not differ between survey years or between men and women. The proportion of treated respondents who had uncontrolled hypertension increased between 1985 and 1995, from 32.6% to 57.4% among men and from 38.0% to 42.6% among women. An increase was seen in the use of calcium-channel blockers (from 2.1% to 19.7%) and angiotensin-converting-enzyme inhibitors (from 5.2% to 25.4%); the proportion of patients receiving combination therapy or diuretics decreased (from 39.6% to 15.6% and from 31.3% to 17.2% respectively). These changes were associated with an increase in the average daily cost of medication from $0.48 to $0.85 per patient. INTERPRETATION: The shift to new antihypertensive drugs was not associated with improved blood pressure control, but it was associated with an increase in average medication costs per patient. Uncontrolled hypertension remains a public health problem.

Adult↗

PubMed1999

Evidence for developmental precursor lesions in epilepsy-associated glioneuronal tumors.

The etiology and pathogenesis of epilepsy-associated local lesions remain largely unknown. Histopathologically, the most frequent lesions comprise gangliogliomas and glioneuronal malformations, i.e., hamartias or hamartomas, with a preferred location in the temporal lobe of young patients. A characteristic histopathological admixture of glial and neuronal elements, the focal appearance and the benign clinical behaviour suggest a malformative nature. So far, no molecular genetic alterations specifically involved in the pathogenesis of these glioneuronal lesions have been identified. However, immunohistochemical analysis revealed distinct distribution patterns of oncofetal antigens. The embryonic form of the neural cell adhesion molecule is present within glioneuronal hamartias, indicating an early migrational disorder. Recently, we have observed immunoreactivity for the stem cell marker CD34 in the majority of gangliogliomas and glioneuronal hamartomas. Based on these findings, we propose a common origin of gangliogliomas and glioneuronal hamartomas from a bipotent precursor that undergoes abnormal glioneuronal development.

Antigens, CD34↗

PubMed1999

Corrosion on an internal spinal fixator system.

STUDY DESIGN: Thirteen spinal fixators with 26 stabilization bridges and 52 pedicle screws and a mean length of implantation of 10 months were prospectively examined for corrosion. OBJECTIVES: To determine the type of corrosion and the correlation between the construction of the spinal fixator and the type of corrosion. SUMMARY OF BACKGROUND DATA: Evidence of fretting and crevice corrosion is seen in many stainless steel implants in retrieval studies. Such reactions have not been described in the literature on spinal fixator systems. METHODS: Macroscopic and microscopic alterations in the adjacent tissue were examined, and the corrosive alterations were documented photographically using stereoscopic optical light microscopy. The chemical composition of the implants was determined spectrographically. Microradiography and x-ray fluorescence analysis of the soft tissue were performed. RESULTS: At surgery, tissue discoloration was found in four cases. Histologic examination showed extensive fibrosis, foreign body reaction and inflammation associated with a small number of metal particles, indicating metallosis in five cases. Corresponding particles were detected by microradiography. Corrosion was found on 13 telescopic rods and on two pedicle screws. The alterations on the telescopic rods could be interpreted as crevice corrosion and the alterations in the pedicle screws as fretting corrosion. The two monobloc fixator bridges did not show signs of corrosion. In these implants, the neighboring tissue was macroscopically inconspicuous, and histologic examination showed minimal fibrosis or presence of metal particles. Spectrographic examination of the spinal fixators showed no structural imperfection. CONCLUSIONS: The construction constraints of a spinal fixator make it prone to corrosion. New spinal implants should be examined not only in vitro but also in vivo to ascertain whether corrosion and adjacent tissue reaction occur. Corrosion is one reason to explant the internal fixation system after fusion of the spinal fracture.

Adult↗