ZM447439, a novel promising aurora kinase inhibitor, provokes antiproliferative and proapoptotic effects alone and in combination with bio- and chemotherapeutic agents in gastroenteropancreatic neuroendocrine tumor cell lines

BACKGROUND

Therapeutic approaches to gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are still not satisfactory. A new direction in treatment options could be the novel aurora kinase inhibitor ZM447439, which was previously reported to interfere with the mitotic spindle integrity checkpoint and chromosome segregation, but does not interfere with other kinases when used up to 5 muM.

METHODS

We evaluated the antineoplastic effects of ZM447439 on growth and apoptosis of the GEP-NET cell lines BON, QGP-1 and MIP-101, representing the different malignant tumor types, using standard cell biological tests as crystal violet assays, caspase activation, DNA fragmentation and cell cycle analysis.

RESULTS

ZM447439 dose-dependently inhibited proliferation of all three cell lines with IC(50) values in the nanomolar to low micromolar range. Moreover, aurora kinase inhibition by ZM447439 potently induced apoptosis, which was accompanied by DNA fragmentation and caspase 3 and 7 activation. Furthermore, we observed cell cycle arrest at G(0)/G(1) phase as well as a block in G(2)/M transition. In addition, combined treatment with the chemotherapeutic agents streptozocin and cisplatin augmented significantly the antiproliferative effects of those agents.

CONCLUSION

Aurora kinase inhibition by ZM447439 seems to be a promising new therapeutic approach in GEP-NETs, which should be evaluated in further clinical trials.

Is locking nailing of humeral head fractures superior to locking plate fixation?

The optimal surgical treatment of displaced proximal humeral fractures is controversial. New implants providing angular stability have been introduced to maintain the intraoperative reduction. In a multi-institutional study, we prospectively enrolled and followed 152 patients with unilateral displaced and unstable proximal humeral fractures treated either with an antegrade angular and sliding stable proximal interlocking nail or an angular stable plate. Fractures were classified according to the Neer four-segment classification. Clinical, functional, and radiographic followups were performed 3, 6, and 12 months after surgery. Absolute and relative (to the contralateral shoulder) Constant-Murley scores were used to assess postoperative shoulder function. Using age, gender, and fracture type, we identified 76 pairs (152 patients) for a matched-pairs analysis. Relative Constant-Murley scores 12 months after treatment with an angular and sliding stable nail and after plate fixation were 81% and 77%, respectively. We observed no differences between the two groups. Stabilization of displaced proximal humeral fractures with either an angular stable intramedullary or an extramedullary implant seems suitable with both surgical treatment options.

LEVEL OF EVIDENCE

Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Modulation of regulatory T cells and myeloid-derived suppressor cells by sorafenib and sunitinib in renal cell carcinoma patients

e16002

Background: Induction of regulatory T (Treg) and myeloid-derived suppressor cells (MDSC) is a major mechanism for the escape of tumors from immunological control. Increased levels of Treg cells have been described in renal cell cancer (RCC) patients and seem to correlate with an adverse outcome. Furthermore, reduction of Treg has been reported for RCC patients under sunitinib therapy. The aim of our study was to analyse the influence of sorafenib and sunitinib on the frequency of Treg and MDSC in patients with metastatic RCC (mRCC). Methods: The number of T reg, MDSC and lymphocyte subpopulations was analysed by flowcytometry in peripheral blood (pb) of patients (n=19) with histologically confirmed mRCC under treatment with either sunitinib (50 mg/d, n=11) or sorafenib (800 mg/d, n=8). After informed consent blood samples were taken before and during the 1st, 2nd, and 3rd month of therapy. Flowcytometric analysis was performed using fluorochrome labeled antibodies against CD3, CD4, CD8, CD25, CD127, FOXp3, CD33, C14, CD11b and HLA-DR. Results: The baseline level of Treg did not differ from healthy controls. However, there was a significant increase of CD3+CD4+CD25+FOXp3+Treg (13,5% vs. 36,3% of gated cells, p= 0.02) and the ratio FOXp3+/FOXp3- CD3+CD4+ T cells (0,16% vs. 0,56% of gated cells, p= 0.02) in the group of sorafenib-treated patients compared to sunitinib-treated patients during the 1st month of therapy and thereafter. This effect was confirmed in an intragroup analysis. There was no influence of Sunitinib on the frequency of Treg. Analysis of CD33+/HLA-DR-/11b+ MDSC did not reveal any change under treatment with sorafenib or sunitinib. Conclusions: Sorafenib, but not sunitinib, leads to an early and sustained increase of Treg in pb of mRCC patients. A negative influence of sorafenib on primary immune responses has been described and has mainly been attributed to functional impairment of dendritic cells (DC). Whether altered DC function under sorafenib is responsible for the induction of Treg in RCC patients will have to be addressed in future studies. In immunoresponsive tumors such as RCC, immunological effects of kinase inhibitors are particularly relevant for the design of combination trials with immunotherapeutic agents.

No significant financial relationships to disclose.

Engraftment kinetics and hematopoietic chimerism after reduced-intensity conditioning with fludarabine and treosulfan before allogeneic stem cell transplantation

Reduced-intensity conditioning with fludarabine and treosulfan before allogeneic stem cell transplantation (SCT) was introduced several years ago. Although its feasibility has recently been proven, only limited data are available on myelotoxicity, engraftment kinetics, and the significance of hematopoietic chimerism using this novel conditioning regimen. To clarify these open questions, we analyzed 27 patients with various hematological diseases, who received allogeneic SCT preceded by fludarabine/treosulfan conditioning. Further assessment endpoints included graft-vs-host disease (GvHD), mortality, and overall survival (OS). Allogeneic SCT was followed by neutropenia (absolute neutrophil count < or = 0.5 x 10(9)/l) and thrombocytopenia (platelets < or = 20 x 10(9)/l) in all patients. All patients showed stable neutrophil engraftment, and all except one had stable platelet engraftment. Grades II-IV acute GvHD was found in 48% of patients, whereas 52% developed chronic GvHD. The treatment-related mortality on day +100, 1 year after SCT, and at the last follow-up was 11, 26, and 33%, respectively. We found complete chimerism rates of 46, 57, and 72% on days +28, +56, and at the last follow-up or before death, respectively. The underlying malignancy tended to relapse more frequently in patients with mixed chimerism than in those with complete chimerism on day +28 as well as on day +56 (not significant). Additionally, no significant association was found between hematopoietic chimerism and donor type, GvHD, or OS, respectively. We conclude that reduced-intensity conditioning with fludarabine and treosulfan before allogeneic SCT is myeloablative, provides stable engraftment, and leads to complete chimerism in the majority of patients.

Reduced-toxicity conditioning with fludarabine and treosulfan prior to allogeneic stem cell transplantation in multiple myeloma

In recent years, reduced-intensity conditioning (RIC) regimens before allogeneic stem cell transplantation (SCT) are increasingly used in patients not eligible for conventional conditioning. We did a retrospective, multicenter analysis to assess the feasibility of conditioning with fludarabine and treosulfan before allogeneic SCT in multiple myeloma patients. Thirty-four patients with a median age of 51.5 years were included in the analysis. All patients underwent myeloablation after conditioning followed by stable engraftment, and 29 of 31 evaluable patients (94%) showed early complete hematopoietic chimerism. Non-hematological toxicities were limited and encompassed mainly fever in neutropenia and infections. Grade II-IV acute and chronic graft-versus-host disease was observed in 33 and 39%, respectively. With a median follow-up of 708 days (range 60-1729 days), the median progression-free survival was 180 days. The treatment-related mortality was 10% on day 100 and 25% after 1 year. The median overall survival has not yet been reached. Our data indicate that conditioning with fludarabine and treosulfan before allogeneic SCT is feasible in intensively pretreated multiple myeloma patients and leads to stable engraftment and complete hematopoietic chimerism. Randomized trials are warranted to determine if this approach might be incorporated in an algorithm of multiple myeloma treatment.

Long-term follow-up of peripheral blood stem cell transplantation from mismatched related and unrelated donors

Allogeneic stem cell transplantation (SCT) is best performed with an HLA-identical sibling donor (matched related donor, MRD) to reduce the risk of early complications such as acute graft-vs.-host disease (aGvHD). However, as only about 30% of recipients have an MRD for this potentially curative approach, the use of family donors with one or two mismatches in the HLA-antigens (mismatch related donor, MMRD) or fully matched unrelated donors (MUD) (''alternative donors'') has been introduced in the allogeneic SCT setting in recent years. To evaluate the feasibility of allogeneic SCT from alternative donors by using peripheral blood stem cells (PBSC) we initiated a prospective, phase II study in 1996. From April 1996 to July 1998, 18 patients with various hematological malignancies underwent allogeneic SCT from alternative donors (two patients with MUD and 16 patients with MMRD). All patients received stable engraftment and none of the patients had graft rejection. The rate of aGvHD (grades II-IV) and the relapse rate at last follow-up (seven to nine yr after SCT) were with 40% and 24%, respectively, comparable with those found in patients receiving allogeneic SCT from MRD. However, five yr after allogeneic SCT only 17% were alive, which was mainly due to the treatment-related mortality (TRM) rate of 59%. We conclude that allogeneic PBSC transplantation by using alternative donors is associated with an unsatisfying long-term TRM rate. The significance of TRM and particular late deaths has to be evaluated further in this transplantation setting.

Optimised surgery (so-called TME surgery) and high-resolution MRI in the planning of treatment of rectal carcinoma

BACKGROUND

Since November 1998, we have applied the concept of total mesorectal excision (TME) to rectal carcinoma together with a standardised pathological quality assessment. Participation in the European MERCURY study [The MERCURY Study Group Radiology (in press), 2006] required us to establish the indication for neoadjuvant radiochemotherapy on the basis of an magnetic resonance imaging (MRI) scan. The aim of the present retrospective study is to evaluate the quality of the surgery, the efficacy of the MRI and the oncological outcomes achieved.

MATERIALS AND METHODS

Between November 2001 and October 2005, 68 out of 109 patients with carcinoma of the rectum were submitted to radical surgery in curative intent and 23/68 (34%) were given neoadjuvant therapy. In an interdisciplinary study group, each patient was evaluated pre-operatively and post-operatively using standardised MRI and histopathological methods.

RESULTS

The quality of surgery was established on the basis of the pathological examination of the surgical specimen. The rates of incomplete mesorectal excision, intra-operative tumour cell dissemination and positive circumferential margins were all low at 4%, 7% and 3%, respectively. The effectiveness of MRI proved to be greatest in predicting the tumour status at the circumferential resection margin: in the admittedly limited number of patients it proved possible to correctly predict the tumour status for every patient. The assessment of the anatomic extent of the primary tumour and of the regional lymph node metastasis according to the TNM system, in contrast, was considerably less successful at 73% and 75%, and 37% and 57%, respectively.

CONCLUSION

By applying the TME concept and MRI-based therapy planning, excellent results can be achieved and, at the same time, the number of patients requiring neoadjuvant treatment is considerably reduced.

Seroprevalence of human granulocytic anaplasmosis in Berlin/Brandenburg, Germany: an 8-year survey

This study investigated the seroprevalence of antibodies against Anaplasma phagocytophilum in Berlin/Brandenburg, north-eastern Germany. During 1994-2001, 422 sera from patients with proven tick-exposure (specimens with antibodies against Borrelia burgdorferi) were compared with 249 control sera. Using indirect fluorescent antibody testing, significantly more positive samples were detected among Borrelia antibody-positive specimens (4.5%, 95% CI 2.5-6.5%) than among controls (1.2%, 95% CI 0.5-1.9%; p < 0.05). While six (2.2%, 95% CI 1.3-3.1%) samples were positive among Borrelia antibody-positive sera between 1994 and 1997, 13 (8.7%, 95% CI 6.9-10.5%) were positive between 1998 and 2001 (p < 0.01), indicating an uneven annual seroprevalence.

UV radiation and cancer prevention: what is the evidence?

The health benefits of sunlight and the risk of skin cancer from UV exposure are still controversial. The literature was analyzed in terms of reviews, controlled and epidemiological studies for the relationships between sunshine exposure and overall cancer mortality, as well as mortality from cancer of the prostate, colon and breast. The residential and/or occupational sun exposure rate seemed to be positively correlated with a lower risk of overall morality due to organ cancer. A normal vitamin D status appeared to be an important precondition, via the local and autocrine synthesis of 1,25(OH)2D3 in the target tissues. The vitamin D hormone system is necessary for cell proliferation and differentiation; different types of vitamin D receptor gene polymorphism seemed to be associated with cancer cell growth. The health benefits of sunlight appear to outweigh the risk of skin cancer. However, the optimal UV exposure, the target level of circulating vitamin D, and whether vitamin D is the only pathway are still undetermined.

Comparison of metric analysis of spinal structures, exemplarily of the ligamentum flavum, obtained with CT and MRI

PURPOSE

Comparison of metric analysis of spinal structures, exemplarily of the ligamentum flavum, obtained with computed tomography (CT) (soft tissue window and bone window) and magnetic resonance imaging (MRI) (T1 and T2 weighted images).

MATERIAL AND METHODS

Forty-six lumbar ligamenta flava of 46 patients (25 women and 21 men) were examined at a Somatom Plus 4 (Siemens, Erlangen, FRG) and at a 1.5 T clinical scanner (Magnetom Vision, Siemens, Erlangen, FRG). Two independent neuroradiologists measured the thickness of the ligamenta flava in mm. Statistics included Pearson's correlation coefficient and the intra-class correlation coefficient.

RESULTS

Mean values did not differ significantly. The correlation coefficients varied between 0.69 and 0.98. The best correlation occurred comparing the same techniques in different windowing and weighting (CT: r = 0.98; MRI: r = 0.95). Correlating different techniques the combination of CT bone window and T1 weighted images presented the best result (r = 0.75).

CONCLUSIONS

Because of the excellent correlation between the examined techniques CT as well as MRI can equally be used to measure distances of spinal structures.

Atherosclerosis: current concepts of pathophysiology and pharmacological intervention based on trial outcomes

Atherosclerosis related cardiovascular diseases are the leading cause of death in western societies. The clinical manifestations are chronic arterial obstructions or acute arterial occlusions in various vascular territories. The pathogenesis is only understood in part as yet. Arterial wall abnormalities, blood composition abnormalities and hemodynamic alterations are generally accepted to be causative (Virchow's triad). The key role is played by macrophages in the subendothelial space that are activated immunologically by oxidized LDL particles via the scavenger receptor pathway. Recently, endothelial dysfunction due to oxidative stress was identified as a priming factor in the course of the development of atherosclerotic plaques. Shear stress-induced microinjuries of the endothelium in hemodynamically compromised regions together with local coagulation activation associated with microinflammation of the plaque are currently thought to cause plaque rupture. This event is the reason for local clot formation and ultimate organ infarction. Treatment success is still insufficient, however some progress during the last decade is reflected by the improving outcome of atherosclerosis associated cardiovascular diseases. Evidence from clinical trials supports the efficacy of statins, antiplatelet agents, antihypertensive agents if necessary and omega-fatty acids in patients with overt atherosclerosis. The reduction of mortality achieved by those drugs amounts to: omega-fatty acids -21%, statins -16%, anti-platelet agents -14%, treatment of hypertension -13%. It is impossible to calculate the combined effect of these modalities since in each trial participants received co-medication containing agents tested in other trials.

[Blood coagulation in normotensives and hypertensives in relation to their body mass index]

BACKGROUND AND PERSPECTIVE: Various parameters of the coagulation cascade and fibrinolysis are important predictors of myocardial infarction and stroke, for which hypertension is a risk factor. It is unclear whether an elevated blood pressure by itself can produce activated clotting.

PATIENTS AND METHODS

Coagulation tests were done on overweight hypertensive (n=40); aged 49 +/- 8 years; group 3), overweight normotensives (n=19; aged 51 +/- 8 years; group 2) and normal-weight normotensives (n=20; aged 51 +/- 8; group 1).

RESULTS

Plasminogen-activator-inhibitor 1 (PAI-1), a measure of impaired fibrinolysis, was elevated in group 2 (20.5 +/- 11 U/ml; p < 0.001), compared with group 1 (11.6 +/- 6 U/ml), and was even higher in group 3 (27.5 +/- 9 U/ml; p < 0.05). Fibrinogen and factor VIII, parameters that promote clotting, were elevated in group 2 (360 +/- 61 mg/dl and 143 +/- 15 %, respectively; p < 0.001), and in group 3 (368 +/- 63 mg/dl and 146 +/- 18%; p < 0.001) compared to group 1 (304 +/- 40 mg/dl and 127 +/- 17%). Correspondingly, fibrin monometers, a measure of intravascular coagulation, were elevated in group 3 (p < 0.05) and partial thromboplastin time (PTT) decreased (p < 0.001). Pearson correlation showed a significant (p < 0.001) positive relationship between PAI-1 and body mass index (BMI) (0.539), triglycerides (0.512), blood pressure (0.388 to 0.534), fibrinogen (0.404, and a negative one with HDL-cholesterol (0.625). BMI also correlated with fibrinogen (0.509; p < 0.001) and factor VIII (0.337; p < 0.01).

CONCLUSIONS

Fibrinolysis and activated coagulation are reduced in hypertensive subjects: this favours the occurrence of myocardial infarction and stroke. In addition to the level of blood pressure, the extent of the changes are effected especially by BMI and metabolic risk factors.

Markers of coagulation, fibrinolysis and angiogenesis after strenuous short-term exercise (Wingate-test) in male subjects of varying fitness levels

It was the aim of the study to analyse the haemostatic system during a high standardized intensive short-term (30 s) exercise (anaerobic Wingate test). Blood samples were taken from 15 male subjects before (t0 ), and within 2 (t1 ), 9 (t2 ) and 30 min (t3 ) after the test. We found that the partial thromboplastin time was markedly shortened, whereas the prothrombin time increased slightly from t0 to t1 (p < 0.002) and remained elevated (t3, p < 0.046). Factor VIII increased from t0 to t1 (p < 0.001) and remained elevated as well (t3, p < 0.001). Fibrin monomers were approximately 15 times higher immediately post-exercise (t1, p < 0.001) and continued to be elevated (t3, p < 0.004). The tissue plasminogen activator increased by 4 times after exercise (t1, p < 0.001) and remained elevated (t3, p < 0.002). The d-dimers increased from t0 to t1 (p < 0.001) as well and remained elevated (t3, p < 0.005). Thrombopoietin concentrations were unchanged, whereas the vascular endothelial growth factor increased immediately post-exercise (t0 to t1, p < 0.011 resp. at t2 p < 0.019) and returned to the control level at t3 (p < 0.878). In conclusion, it was found that prothrombotic markers and, even more pronounced, those of the fibrinolytic system were increased. The study provides evidence that due to intensive short-term exercise the balance of the haemostatic system is shifted to a higher equilibrium. Theoretically, the data show that in the case of a subject with risk factors such as impaired fibrinolysis, unfavourable conditions cannot be excluded.

[Shock wave therapy for recalcitrant plantar fasciitis with heel spur: a prospective randomized placebo-controlled double-blind study]

AIM

Efficacy of low-energy shock wave therapy for recalcitrant plantar fasciitis.

METHOD

32 patients were randomly assigned into real and placebo ESWT groups, treatment comprised 1000 impulses of 0,08 mJ/mm 2 at 14 kV (OssaTron OSA 120, HMT AG, Switzerland) in 12 cases repeated after six weeks or placebo (energy-absorbing foil). Follow-up evaluation (19, 32 and 48 wks.) included specific questionnaire, clinical-functional examination and measurement of plantar pressure while walking (Emed AT-4. pedograph, Novel GmbH, Munich). Examiner and patients were blinded.

RESULTS

88 % of the treatment group were pain free or had good results. None of the placebo group were pain free, 33.3 % had good results (Roles and Maudsley Score). The treatment group showed significantly better outcome for morning and resting pain, pressure stamp-tolerance and walking ability. Pedography did not show a clear correlation between pain relief and load pattern.

CONCLUSION

The results of this study corroborate the value of ESWT for recalcitrant plantar fascitis. As a non invasive technique with low side effects, it can complement the row of conservative treatments.

Effect of adjuvant imiquimod 5% cream on sustained clearance of anogenital warts following laser treatment

OBJECTIVES

Imiquimod is an immune response modifier that has demonstrated a good efficacy and relatively low recurrence rates in comparison to other genital wart treatment modalities. The primary objective of this open-label study was to evaluate the effect on sustained clearance of treated lesions and the safety of patient-applied topical imiquimod after laser therapy of external anogenital warts.

METHODS

After laser treatment of visible external anogenital warts the ablated region(s) were treated with imiquimod 5% cream three times/week over 12 weeks beginning when the wound healing process was completed, followed by a six-month treatment-free observation period for the assessment of sustained clearance of treated lesions.

RESULTS

A total of 211 male and female patients was enrolled in the study. After 12 weeks of treatment, 65.4% of all patients showed sustained clearance. During the treatment period, 15 patients (7.1% of 211 patients) presented with recurrent warts in the treated areas, and 58 (27.5%) patients were excluded for other reasons. During the six-month follow-up period, ten additional patients (7.3% of 138 patients) developed wart recurrences. The application of imiquimod 5% cream was well tolerated. The number of patients with adverse events related to study medication declined from the first month of treatment until the end of the third month. Most frequently, mild to moderate itching, burning, pain and erythema were reported.

CONCLUSIONS

After laser therapy and sufficient wound healing, administration of imiquimod 5% cream three times/week appears to be safe and to reduce the incidence of wart recurrences.

The uptake of dental services by elderly Germans

OBJECTIVE

The aim of the study was to assess the uptake of dental services by the old and very old population within the scope of the Berlin Aging Study (Berliner Altersstudie BASE).

DESIGN

A multi-disciplinary structured interview was performed on 928 subjects, aged from 70 to 103 years of whom 516 persons volunteered to take part in a 14-session intensive protocol. Six representative study groups were matched for age and gender. Subjects were asked to recall the timing of their most recent dental visit. Data were validated by sending for dental records and compared with all study participants from the multi-disciplinary intake assessment. Data were related to age group, dental state, dementia and education.

RESULTS

Reported last contact with dental services ranged from 2 weeks to 52 years (median 18 months) with a higher time lapse in the study groups aged 85 and older. Dentate subjects had seen their dentist more recently than edentate subjects. Higher education correlated with an increased dental utilisation. Subjective memory on the time lapse since the last dental appointment coincided in 13% of the subjects with available dental records (n=84), was misjudged between one and six months in 55%, and by more than six months in the remainder. Moderately or severely demented subjects who remembered their last dental appointment (n=48 of 70) showed no consistently different utilisation to healthy or mildly demented study participants.

CONCLUSION

Edentate old and very old subjects show the least frequent utilisation of dental services. Data on motivation and barriers to care are needed to develop strategies to improve the use of dental services and thus promote oral health in late life.

[Expression of galectin-3 in thyroid gland and follicular cell tumors of the thyroid. A critical study of its possible role in preoperative differential diagnosis]

Galectin-3 belongs to a group of endogenous lectins with an affinity to glycoconjugates containing beta-galactoside residues. It has been detected in numerous tissues and studied in connection with tumor growth, dedifferentiation, and metastasis. Only few studies have dealt with galectin-3 detection in tumors of the thyroid gland and with its possible role for differential diagnosis. We studied 118 cases of thyroid gland tumors with a monoclonal antibody against galectin-3; we compared the preparations by a semiquantitative score to determine differences in expression. Normal thyroid gland tissue, goiter tissue, and tissue with functional enhancement were largely negative for galectin-3. Adenomas with a typical cytological pattern were predominantly negative, but a focal positive reaction in single cells and cell groups or follicles was possible. Almost all papillary carcinomas showed a distinct galectin-3 expression. While findings in follicular carcinomas and oxyphilic adenomas and carcinomas were very uneven, with both positive and negative tumors, the galectin-3 reaction can be helpful in recognizing follicular variants of the papillary carcinoma. Investigation of the biological significance of tumors should always be cautious and consider known histological criteria for malignancy.

Tablet fluoridation influences the calcification of primary tooth pulp

This study was conducted to determine the influence of long-term tablet fluoridation on primary pulp calcification by light microscopy. Twenty-four caries-free primary molars (after continuous postpartally initiated 1- to 10-year tablet fluoridation) were compared to 17 primary molars of children without fluoride prophylaxis. Pulp calcification in children with tablet fluoridation was significantly more frequent and more pronounced than in untreated children (p = 0.001). Besides the known pulp stones, the prophylaxis group evidenced a special form of calcification consisting of fibrodentin-like hard tissue not observed in the untreated children. These hard tissue bodies developed "intramurally" on the pulp floor and the inside of the dental roots with an irregular extramural spread into the coronal and radicular pulp by displacement and fibrotization of the pulp tissue. Moreover, some of the teeth had more or less extensive areas of interglobular dentin. The affected teeth were ankylosed in the area of the bi- and trifurcation and on the inside of the roots and were thus infra-occluded. Although the duration of tablet fluoridation has no statistically significant influence on pulp calcification, there is a correlation between extensive pulp calcification, postnatally initiated fluoride prophylaxis and the infraocclusion of primary molars.

Detection and prognosis of recurrent gastric cancer--is routine follow-up after gastrectomy worthwhile?

BACKGROUND/AIMS

Although routine follow-up after surgery for gastric cancer is recommended its value after gastrectomy has not been evaluated.

METHODOLOGY

All patients who underwent gastrectomy for gastric cancer entering the routine follow-up program between January 1987 and August 1996 were identified. The patients studied were those with either histologically proven recurrence or those in whom recurrence was highly probable from clinical course. Two groups were compared. The first group comprised the patients whose recurrence was detected by routine follow-up prior to the development of clinical signs (asymptomatic group). The second group consisted of the patients who developed clinical symptoms due to a recurrence that was detected subsequently (symptomatic group). The main parameters were the time until recurrence occurred, the pattern of recurrence, treatment and survival.

RESULTS

Out of 184 patients entering the routine follow-up 135 patients had undergone potentially curative gastrectomy. Sixty-seven patients (49.6%) had recurrences. Only 15 (22.3%) belonged to the asymptomatic group and 52 (77.7%) to the symptomatic one. The time until recurrence occurred was not different between the 2 groups (17.1 vs. 18.0 months). Chemotherapy was performed more frequently in the asymptomatic group and survival was longer (8.4 vs. 5.9 months). This difference was due to the time the patients remained asymptomatic (average 43 months). No effect of either early detection or chemotherapy was seen. In the asymptomatic group distant recurrence was common while recurrence in the symptomatic group was more often local but this difference did not reach statistic significance.

CONCLUSIONS

Routine follow-up after gastrectomy for gastric cancer does not contribute to early detection of gastric cancer recurrence. It has no benefit with respect to treatment and survival of patients with recurrent disease and should therefore be reduced to symptomatic and psychological aftercare.

Amalgam fillings and cognitive abilities in a representative sample of the elderly population

OBJECTIVES

The ongoing controversial discussion about a possible negative effect of amalgam fillings on the cognitive abilities and the pathogenesis dementia was the objective of the present study.

SAMPLE

A total of 300 patients aged from 70 to 103 years were selected from the multidisciplinary 'Berlin Aging Study' (BASE). The sample was heterogeneous concerning lifestyle, education and social prestige. According to their dental state subjects were allocated into three groups: edentate > or = 20 years (I) and residual teeth without (II) or with (III) amalgam restorations. All groups were matched for age and gender.

DESIGN

Dental examinations and various psychiatric as well as psychological assessments were carried out by professionals within the protocol of the BASE. Tests were chosen to reveal the presence and degree of dementia and assess cognitive abilities such as 'perceptual speed', 'reasoning', 'memory', 'fluency' and 'knowledge'.

RESULTS

The present findings negate a correlation between the dental state and the pathogenesis of dementia and the physiological age-related decline in cognitive abilities. Thus the presence of amalgam fillings did neither correlate to a demented mental condition nor an impaired cognitive performance.

[Projection of the number of multiple sclerosis patients in Germany]

For determining the prevalence of multiple sclerosis (MS) in Germany, the outcomes of several epidemiological studies are available. If these rates are transferred to Germany as a whole, figures result of 67,000 to 138,000 MS patients in all. The differing prevalence rates may be caused by various problems in finding patients, the epidemiological area, and different population structures. To avoid these difficulties, a new approach for calculating the number of patients with diagnosed MS was chosen based on representative samples taken from the groups of physicians involved in MS treatment. The disadvantage of this approach is that it does not allow any questioning of the diagnosis. Projecting the results in this way and their subsequent compilation--taking "double treatments" into consideration--showed a total of 122,000 patients with diagnosed multiple sclerosis in Germany. This figure corresponds to a prevalence rate of 149.1 per 100,000 inhabitants and is within the range found by Poser et al. [19]: 127 per 100,000 excluding the diagnostic category "possible multiple sclerosis" and 170 per 100,000 including it.

Activation of blood platelets in response to maximal isometric exercise of the dominant arm

Isometric exercise is a popular form of physical activity for many people. Only few studies exist on the effects of this type of exercise on the hemostatic system. Eleven male healthy subjects (21-42 years) of varying fitness levels were investigated before, immediately after and 10 min after strenuous isometric exercise of the dominant arm. Blood samples were drawn by repetitive puncture from both the exercising and the contralateral arm. The following variables were studied: Prothrombin time and partial thromboplastin time as group tests for the plasmatic coagulation system; platelet count as well as p-selectin expression for the platelet system; tissue plasminogen activator (t-PA) activity and antigen for the fibrinolytic system. The partial thromboplastin time was shortened immediately after maximal isometric exercise of the dominant arm, the prothrombin time remained unchanged. No change was found in the platelet count, but a marked p-selectin expression was observed immediately after maximal isometric exercise of the dominant arm (p < 0.05) and even in the resting contralateral arm. Values returned to baseline after 10 min. There was a slight increase of t-PA antigen concentration and white blood cell count at maximal isometric contraction which did not occur in the resting arm, although changes over the 3 time points were significant in both arms. Maximal isometric exercise leads to platelet activation in both arms, a slight aPTT decrease and t-PA antigen increase in local blood stream. As compensatory fibrinolytic changes do not occur, it is an open question whether isometric exercise increases the potential risk of thromboembolism.

The prevalence of incipient tubular dysfunction, but not of glomerular dysfunction, is increased in patients with diabetes onset in childhood

The study investigated the prevalence of incipient renal dysfunction in two cohorts with identical duration of type I diabetes but with childhood or adult onset of the disease. The pattern of glomerular (albumin, alb) and tubular (alpha(1)-microglobulin, alpha(1)-m, and N-acetyl-beta-D-glucosaminidase, NAG) urinary protein excretion was studied in 97 patients with diabetes onset before the age of 16 years and in 53 patients with manifestation of the disease after this age. Diabetes duration was comparable in both groups [9.0 years (1.5-40.0) versus 9.0 (1.0-34.0), p 30 microg/g creatinine), patients with diabetes onset in childhood showed significantly higher excretion of NAG compared to those with diabetes onset after the age of 16. The excretion of both tubular markers (alpha(1)-m and NAG) correlated significantly with HbA(1c)-values in both groups. In multiple regression analysis, tubular proteinuria (alpha(1)-m) and diabetes duration correlated significantly to microabuminuria (multiple R = 0.60, p < 0.001). These data suggest that there is no difference concerning the prevalence of incipient diabetic glomerulopathy between patients with an early or a late onset of diabetes. However, a more frequent impairment of tubular function was found in young patients with diabetes onset in childhood, which might be due to a non-optimal glycemic control in this population.

Octreotide suppresses the incretin glucagon-like peptide (7-36) amide in patients with acromegaly or clinically nonfunctioning pituitary tumors and in healthy subjects

OBJECTIVE

To study the effect of octreotide on glucagon-like peptide (7-36) amide (GLP-1) and insulin secretion in patients with pituitary tumors during preoperative treatment and in healthy subjects.

DESIGN

Open design prospective clinical study.

METHODS

Eighteen patients with pituitary macroadenomas (13 clinically nonfunctioning (NFA; 11/13 had GH insufficiency), 5 GH secreting (GHA)) received preoperative octreotide treatment: 3x100 microg/day s. c. for 3 months, and 3x500 microg/day s.c. for an additional 3 months. Seven healthy subjects received (for ethical reasons) only 3x100 microg/day for 10 days. A standardized meal (St-M) test, oral glucose test (oGTT) and i.v. glucose test (ivGTT) were done before octreotide therapy, on days 1, 2 and 3 (D1,2,3), after 3 months (M3) and 6 months (M6) of octreotide treatment in the patients, and before treatment, on D1,2,3 and on D8,9,10 of octreotide treatment in the healthy subjects. Serum GLP-1, insulin and GH as well as plasma glucose were determined for 180 min (oGTT, St-M) or 120 min (ivGTT).

RESULTS

Pretreatment fasting GLP-1 concentrations as well as integrated responses (area under the curve 0-180 min) to oGTT and St-M were not significantly different between NFA, GHA and healthy subjects. During the oGTT, octreotide initially almost abolished the early (0-60 min) and diminished the late (60-180 min) GLP-1 and insulin responses in patients and healthy subjects. At M6 integrated insulin responses had significantly recovered, while the increase in GLP-1 response failed to reach significance (GLP-1: 56.5% of pretreatment at D2 versus 93.5% at M6 and 41.2 versus 63.1% in NFA and GHA respectively; insulin: 50.2 versus 71.2% and 35.5 versus 70. 4%). An escape of GLP-1 and insulin in healthy subjects (D2 versus D9) was not significant. Intestinal glucose absorption was apparently not reduced, since the early glucose rise was similar before and during octreotide treatment. During the St-M the GLP-1 and insulin responses were similarly suppressed by octreotide and recovered during ongoing treatment (GLP-1: 49.6% of pretreatment at D1 versus 79.0% at M6 in NFA and 46.9 versus 52.9% in GHA. Insulin: 27.6 versus 83.9% and 23.5 versus 54.4%). The escape was significant in NFA but not in GHA. In the healthy subjects the escape was already significant on D8 (GLP-1: 39.5% of pretreatment at D1 versus 68.3% at D8; insulin: 36.6 versus 53.8%). During the ivGTT GLP-1 did not increase. The early insulin response (0-30 min) was abolished by octreotide, followed by a reduced peak at 60 min. The reduction of the integrated insulin response during ivGTT was similar to that during oGTT. An insulin escape reached significance only for NFA (52. 6% of pretreatment at D3 versus 66.7% at M6). Glucose tolerance (KG value) deteriorated and did not improve during ongoing treatment. Octreotide suppressed the median GH concentration (8h profile) of the GHA patients from 10.3 microg/l (pretreatment) to 5.8, 6.3 and 3. 7 microg/l at D4, M3 and M6 with no escape. GH was 1.5 microg/l postoperatively.

CONCLUSIONS

Octreotide abolishes the early and diminishes the late GLP-1 and insulin responses to oGTT and St-M in NFA and GHA patients and in healthy subjects. In contrast to GH, both hormones partially escape from suppression during ongoing therapy. During treatment with our conventional octreotide doses suppression of insulin secretion is maximal. Under these conditions an effect of the additional loss of GLP-1 is not apparent. Basal GLP-1 concentrations and integrated responses to oGTT and St-M were similar in healthy subjects and in patients with GH excess or GH insufficiency.

Local metronidazole application in maintenance patients. Clinical and microbiological evaluation

The purpose of this investigation was to evaluate the clinical and microbiological effect of local antibiotic therapy in comparison with subgingival scaling and root planing in a randomized semi-masked study. Forty-six recall patients who completed systematic periodontal therapy 6 to 24 months prior to the study were enrolled. The inclusion requirements were at least one site with probing depth > or = 5 mm in each quadrant, no scaling, and no antibiotic therapy during the last 6 months. After randomization each patient received 2 different treatments: in 2 quadrants metronidazole 25% dental gel was applied subgingivally to the pockets at day 0 and day 7; scaling and root planing was carried out in the 2 other quadrants, one at day 0 and in the remaining quadrant at day 7. Subgingival microbiological samples were taken from each patient before treatment and on days 21, 91, and 175 after the treatment. The analyses were carried out by indirect immunofluorescence assay. At all treated sites probing depth (PD), clinical attachment level (CAL), and bleeding on probing (BOP) were recorded on days 0, 21, 91, and 175. Both treatments resulted in PD reduction and CAL gain. PD reduction was statistically significant (P < 0.01) for both treatment modalities after 6 months. The CAL gain was not significant for either treatment. There was no statistical significance between scaling and antibiotic therapy. Treponema denticola, Porphyromonas gingivalis, and Prevotella intermedia were significantly reduced after therapy; however, there were no statistically significant differences between treatments. If Actinobacillus actinomycetemcomitans was present before therapy, it was also present after treatment in both groups. The conclusion is that, in recall patients, local application of metronidazole and scaling and root planing showed similar clinical and microbiological effects without statistically significant differences.

Effect of the somatostatin analog octreotide on gastric mucosal function and histology during 3 months of preoperative treatment in patients with acromegaly

OBJECTIVE

To study the effects of the somatostatin analog octreotide on gastric mucosal function and histology during short-term (3 months) preoperative treatment in patients with acromegaly.

DESIGN

Open design clinical study.

METHODS

10 patients were studied before treatment with octreotide (pre-tx), on day 1 of 300 microg octreotide/day (d300), after 1 week on 300 (w300), 600 (w600) or 1500 (wl500) microg octreotide/day, and after an additional 2.5 months on 1500 microg octreotide/day (M3). An 8h gastrin profile was obtained and ambulatory intragastric 23h pH-metry carried out at the indicated time points. Gastroscopy was performed at pre-tx and M3 and multiple mucosal biopsy specimens taken.

RESULTS

The mean serum gastrin concentration at first declined during octreotide therapy to a nadir at w1500, then recovered despite ongoing therapy (probably in response to reduced gastric acidity) and was similar to pre-tx values at M3 (mean+/-S.E.: 87+/-26, 50+/-11 and 98+/-46ng/l for pre-tx, w1500 and M3 respectively; P<0.05, pre-tx vs w1500). Gastric acidity had also declined at d300(P<0.05, d300 vs pre-tx), then recovered (despite the increase in the octreotide dose), but declined again at M3 (mean pH (95% confidence interval): 2.4 (1.7-3.2), 3.3 (2.4-4.3), 2.6 (1.8-:3.5, n=8) and 2.9 (1.6-4.2, n=7) at pre-tx, d300, w1500 and M3 respectively). The gastrin concentration at M3, although similar to pre-tx values, remained inadequately low for the reduced gastric acidity. The reduction in gastric acidity was marked during the daytime (0900-2200 h; P<0.01, d300 vs pre-tx and P=0.028, M3 vs pre-tx). However, while the stimulated postprandial gastric acid secretion was reduced at d300 (P<0.01, d300 vs pre-tx) and at M3 (n=7; P=0.027, M3 vs pre-tx), fasting and preprandial acidity was not affected. During the night, gastric acidity was reduced from 2200 to 0300 h, but the reduction was less marked than during the daytime. Paradoxically, the physiological intermittent late nocturnal reduction in acidity ('pH peaks' (0300-0800 h)) was abolished rather than enhanced. No patient acquired new Helicobacter pylori infection. The mean gastritis scores for antrum and body (n=8, Sidney classification) increased marginally from 1.7 to 1.9 (chronicity) and from 0.7 to 0.9 (atrophy), while the activity score was slightly reduced from 1.2 to 1.0.

CONCLUSIONS

Three months of preoperative octreotide treatment profoundly and persistently altered gastric mucosal function (gastrin suppression, reduced acidity), but caused only minor variations in the pre-existing gastritis scores.

Results of somatostatin receptor scintigraphy do not predict pituitary tumor volume- and hormone-response to ocreotide therapy and do not correlate with tumor histology

The value of somatostatin receptor scintigraphy (SRS) to predict the effect of somatostatin analog therapy on pituitary adenomas is not clear, due to the use of different radiopharmaceuticals (123I-Tyr3-octreotide and 111In-pentetreotide) and the small number of patients in previous studies. We used 111In-pentetreotide scintigraphy in 49 patients in order to (i) correlate SRS results with basal tumor volume as well as volume- and hormone-response to 3 months of octreotide therapy (Oct-Tx). (ii) identify tumor remnants after incomplete surgery and (iii) evaluate any correlation with immuno histology. Twenty-five patients had a GH-secreting adenoma (GH-A, 15 prior to intended surgery, 10 with persistent/recurrent disease after previous therapy). Twenty-four patients had a clinically non-functioning adenoma (NF-A). For SRS, planar and single photon emission computer tomographic images (SPECT) were recorded 4 h and 24 h post injection. SRS grading was as follows: GO, no uptake: G1, uptake comparable to normal pituitary; G2, increased uptake: G3, very intense uptake. G2/3 was seen in 8/25 GH-A and in 12/24 NF-A. Pretreatment tumor volume (magnetic resonance imaging (MRI) tended to be related to 111In-pentetreotide uptake in GH-A with a tumor visible on MRI (G0/1 (n = 10) vs G2/3 (n = 8): 3.6 +/- 1.9 vs 10.5 +/- 6.5 cm3 (mean +/- S.E.), P = 0.051), but not in NF-A (G0/1 (n = 12) vs G2/3 (n = 12): 17.0 +/- 10.1 vs 14.3 +/- 3.6 cm3). SRS did not identify a tumor remnant in the 7 MRI-negative patients with persistent post-operative acromegaly. Basal GH (6-h profile) and IGF-1 in GH-A did not correlate with SRS results (G0/1 (n = 17) vs G2/3 (n = 8), GH: 32.3 +/- 18.2 vs 29.3 +/- 7.4 micrograms/l IGF-I: 851 +/- 80 vs 1038 +/- 153 micrograms/l). During Oct-Tx of GH-A neither tumor shrinkage nor GH suppression was related to SRS results. In 6 NF-A classified as gonadotropinomas (by their plasma glycoprotein hormone or alpha-subunit concentrations, basally and/or in response to TRH) 111In-pentetreotide uptake was not different from that of the non-gonadotropin/non-secreting adenomas. SRS results were not related to the immunohistological subtype in 22 GH-A (monohormonal mixed somatotrope/lactotrope, plurihormonal) or in 22 NF-A (null-cell adenomas, gonadotropinomas silent hormonal adenomas). We conclude that 111In-pentetreotide SRS reflects tumor volume poorly in GH-A and not at all in NF-A. It does not predict the effect of Oct-Tx on the volume of both GH-A and NF-A, nor on the GH concentration in GH-A. 111In-pentetreotide SRS is unable to identify post-operative tumor remnants not visible on MRI.

Lipid profiles and blood pressure: are they risk factors for the development of early background retinopathy and incipient nephropathy in children with insulin-dependent diabetes mellitus?

The objective of this study is to examine the influence of lipid profiles and blood pressure on the development of microvascular complications in adolescents with insulin-dependent diabetes mellitus (IDDM) in a matched pairs study. Patients with early background retinopathy (n = 21) or microalbuminuria (n = 15) and their respective statistical twins participated in the study. Serum total cholesterol, high-density lipoprotein (HDL) cholesterol, fasting triglycerides, glycosylated haemoglobin A1c (HbA1c), and systolic and diastolic blood pressure during 3 years prior to the development of early background retinopathy or incipient nephropathy were examined. The multivariate discriminant analysis demonstrated glycaemic control and HDL cholesterol to be the most important variables related to the development of retinal lesions (84% correctness), and diastolic blood pressure to be associated with microalbuminuria (57% correctness). In addition to poor glycaemic control, different factors seem to be important for the early retinal or renal lesions of juvenile IDDM.

[Evidence for a therapeutic effect of Ginkgo biloba special extract. Meta-analysis of 11 clinical studies in patients with cerebrovascular insufficiency in old age]

Eleven controlled clinical trials were evaluated in a meta-analysis in order to proof the effectiveness of the ginkgo biloba special extract LI 1370 (Kaveri forte). All included studies were placebo controlled randomized double blind studies, using in most of the cases a daily dosage of 150 mg extract. The requirements for the quality of the studies were the basic criteria for the performance of clinical drug tests analysed from the biometrical scope. The analysis of the individual studies revealed that three studies had to be excluded from the meta-analysis according to methodological or objective reasons. In two further studies the evaluation of the physician or the patients was missing, therefore the studies could not be used for the analysis of the "global effectiveness". All other studies were comparable with regard to diagnoses, inclusion and exclusion criteria as well as methodology. Therefore a statistical meta-analysis could be performed for them, analysing the parameters "single symptoms", total score of clinical symptoms and "global effectiveness". For all analyzed single symptoms significant differences could be concluded, indicating the superiority of ginkgo biloba in comparison to placebo. The analysis of the total score of clinical symptoms from all relevant studies indicated that 7 studies confirmed the effectiveness (Ginkgo biloba being better compared to placebo) while only one study was inconclusive (the medications were not different). This relation confirms the therapeutical effectiveness of ginkgo biloba regarding the clinical symptom complex. Finally the parameter "global effectiveness" was evaluated.(ABSTRACT TRUNCATED AT 250 WORDS)

Differences in morbidity and mortality according to type of referral of very low birthweight infants

Maternal and social risk, prenatal and obstetric care, resuscitation and neonatal care in very-low-birthweight infants (VLBW) may vary with the type of referral. In 453 VLBW's (< 1500 g) admitted to our neonatal intensive care unit 1987-1992, we classified transport type as: A: No transport (n = 240), B: Maternal transport (n = 88), C: Infant transport (n = 125). Stepwise multiple discriminant function was determined for the identified factors. The risk of mortality was investigated by logistic regression analysis. In group A, mean maternal age was higher and mothers' social status lower than in groups B and C. In group B, infants were considerably smaller and less mature, but when adjusted for gestational age, suffered less frequently from RDS, obviously due to more frequent induction of lung maturation. In group C, less than half of the infants were resuscitated by a neonatologist. Infants of this group were frequently hypothermic at admission and required prolonged artificial ventilation more frequently. Total VLBW survival averaged 77%, increasing from 69 to 88% within the study period. Total rate of severe intraventricular hemorrhage was 4.8% in surviving infants. VLBW infants with different forms of referral differ in their inherent risk. After maternal transport they have less morbidity despite a higher grade of immaturity. Regionalization of perinatal care for these infants remains the greatest potential for further reduction in infant mortality.

[Surgical ligation of patent ductus arteriosus on the intensive care unit in small premature infants]

This paper summarizes the experience with ligation of persistent ductus arteriosus in prematures performed in the intensive care unit during the years 1986 to 1988. Records of 35 operated prematures on artificial ventilation were analyzed retrospectively. Management and organization of the operation are described. For comparison, records were analysed of 47 prematures, also artificially ventilated, who during the years 1978 to 1986 had to be transported to an operating theatre over a distance of 3 or 10 km for the ligation.

Malaria prophylaxis in travellers to tropical Africa

This study investigated travellers to tropical Africa with regard to prophylactic treatment of malaria. A total of 5703 travellers completed a questionnaire on their flights back to the Federal Republic of Germany; 4116 passengers (73.7%) had visited East Africa, while 808 (14.5%) had been to West Africa. The results indicate that 90.2% took a regular chemoprophylaxis against malaria. Nevertheless, 8.1% of the travellers used no antimalarials and in 9.3% chemoprophylaxis was inadequate due to inappropriate advice; for example, 7.5% still took pyrimethamine-sulfadoxine as prophylactic. Mefloquine was correctly taken by 38.9% of the travellers in East Africa; 12.6% used it in West Africa where it is not necessary. Antimosquito measures have a high priority for travellers to tropical Africa and dissemination of this fact must be improved since only 72.6% followed through on such advice.

Pharmacokinetics of ciprofloxacin in liver cirrhosis

The pharmacokinetics of ciprofloxacin were evaluated in 11 patients (3 patients with impaired renal function) with advanced liver cirrhosis after a single oral dose of 500 mg. Mean serum peaks were 2.80 +/- 1.00 mg/l in 64 +/- 37 min after intake in patients with normal renal function. Elimination was reduced in comparison with healthy volunteers: t1/2 beta 510 +/- 158 min with a total area under the curve of 18.2 +/- 10.3 mg x h/l. Mean recovery of the parent compound from urine was 38 +/- 9% of the dose. In 3 patients with cirrhosis plus poor renal function, elimination was markedly reduced. In patients under 60 years with good renal function, the standard does not require a reduction.

[Improvement of MR tomography of the liver using a multislice gradient echo sequence]

A prospective study of 52 patients with various focal liver lesions was carried out using a multislice-gradient echo sequence and this was compared with spin-echo sequences. The multislice-gradient echo sequence provides the possibility of obtaining heavily T1-weighted images of the entire liver during one examination, thereby reducing the time of the examination. Contrast is significantly better than that of a T1-weighted spin-echo sequence (p greater than 0.05). The multislice-gradient echo sequence examination, taking 5.4 minutes, provides good and diagnostically useful image quality.

[Tumor differentiation by multivariate discriminant procedures in CT absorption analyses]

An attempt is made to utilise so-called absorption analyses in cranial CT for further differentiation of the diagnosis of the various types of space-occupying growths. Characteristic distributions are shown for specific "regions of interest" in meningiomas, glioblastomas and cerebral abscesses before and after contrast medium injections. Clear criteria can be formulated for the differentiation of glioblastoma and cerebral abscess using multivariate discriminance analyses.

Manifestation of carcinogenesis as a stochastic process on the basis of an altered mitochondrial genome

Computer calculations are used to show the feasibility of a concept which explains the manifestation of a pathological cell function from a latent state by the phenomenon of extrachromosomal inheritance (through the mitochondrial genome) in mammalian cells. A hypothesis is submitted in which this principle is applied to the process of carcinogenesis. According to this concept, the manifestation of a tumor cell--after the initiation stage--entirely depends on stochastic events, i.e., random distribution of mitochondria during cell divisions, with an accumulation of the lesion in a few out of many cells. We feel that this concept comprises a better explanation of many characteristics and peculiarities of the phenomenon of carcinogenesis than do attempts which explain tumor formation as a phenomenon caused by mutation in a nuclear genome. A consideration of the principles presented automatically leads to a number of specific consequences with regard to carcinogenesis. Some of these consequences are discussed. They include: 1. the process of malignant transformation should not be irreversible for all the cells of a progeny; 2. the number of mitochondria in a cell type should be inversely correlated to tumor frequency; 3. the latent period should mainly be determined by the cell division rate and the "extent" of the initiating event; 4. susceptibility to carcinogenesis may be substantially higher if the number of mitochondria per cell line is increasing or decreasing, i.e., during the embryonic and fetal periods; 5. heterogeneous types of cells may arise from a single "initiated" cell, and 6. the process of malignant transformation should not necessarily be confined to one generation of the species. In addition, experimental approaches to support the submitted concept are suggested.

CT evaluation of the CSF spaces of healthy persons

Changes in the width of the CSF space throughout life were studied in CT scans of 170 healthy individuals. The internal and external CSF spaces were evaluated using parameters which can also be employed in routine clinical studies. Tables of normal values for the CSF spaces at various ages are presented.