PubMed Health⌕ Search

Biomedical subjects

B Ritter

Publications and source records attributed to B Ritter.

At least 19 recordsLinked to original sources
PubMed1995

Antianginal effect of conventional and controlled release diltiazem in stable angina pectoris.

Two preparations of diltiazem, controlled release (CR) given twice a day (b.i.d.) and plain given 4 times a day (q.i.d.), were compared in a multicentre, double-blind, crossover study in 41 patients with stable angina pectoris. Therapeutic efficacy was assessed with maximal exercise tests, patient recordings on nitroglycerine consumption and angina attacks. No significant differences between the CR and plain tablets were seen in any of the efficacy variables. Maximal workload significantly increased from 127 W on placebo to 146 W on CR tablets and to 147 W on plain tablets. Anginal attacks/week significantly decreased from 11.7 on placebo to 4.9 on CR tablets and to 5.0 on plain tablets. Consumption of nitroglycerine tablets/week significantly decreased from 6.3 on placebo to 2.6 and to 3.4 on CR and plain-tablets, respectively. The number or the seriousness of the adverse events did not differ between the groups. The results imply that diltiazem CR b.i.d. is equally potent and safe as conventional diltiazem q.i.d. in the control of stable angina pectoris.

Aged↗
PubMed1995

Iron deficiency and iron overload in Swedish male adolescents.

OBJECTIVES: The present study was undertaken to confirm or reject recent findings indicating a high prevalence of iron deficiency in Swedish male adolescents; a second aim was to study the prevalence of genetic iron overload. DESIGN: The diagnostic criteria were: anaemia: Hb < 130 g L-1 (a): iron deficiency: serum ferritin (SF) < 12 micrograms L-1 + transferrin saturation (TS) < 16% (b): iron deficiency anaemia a + b. Iron overload: SF (90th percentile) + TS (90th percentile) in repeat tests. SETTING: Central Sweden. SUBJECTS: A total 3975 men aged 18 years studied on enrollment into military service. RESULTS: Serum ferritin averaged 36.8 micrograms L-1. Anaemia was present in 0.5%, iron deficiency anaemia in 0.17% and iron deficiency in 0.4%. If iron deficiency is defined as SF < 16 micrograms L-1, as was recently suggested, the prevalence would be 2.8%. Such a cut-off value would include 73% normal people (false positives). Iron overload had the same prevalence as iron deficiency, 0.4%. CONCLUSIONS: Iron stores, as measured by serum ferritin, are small in young men studied at the end of their growth spurt. However, iron deficiency is rare. Therefore, the present study has not been able to confirm the high prevalence of iron deficiency recently reported. A prevalence of genetic haemochromatosis of 0.4%, confirms earlier findings and would mean that 12.6% of the population are heterozygotic carriers of the iron-loading genes. These findings give no support for a proposed, more effective iron-enrichment of food. It is not needed and can be harmful.

Adolescent↗
PubMed1994

EEG, auditory evoked potentials and evoked rhythmicities in three-year-old children.

According to our working hypothesis, the resonance properties of the brain systems play an important role in internal brain communications (e.g., Başar, 1992; Başar, Başar-Eroglu, Demiralp & Schürmann, 1992). It was assumed that evoked potentials (EPs) reflect brain resonance properties, showing enhancement, time and frequency-locking during the poststimulus period. All these phenomena might be referred to the spontaneous (intrinsic) EEG rhythms according to the excitability rule and the related concept of brain system response susceptibility: a brain system could react to internal or external stimuli producing those rhythms or frequency components, which have already been present in intrinsic or spontaneous activity (Başar, 1980). In order to test the hypothesis of response susceptibility, in the present paper we used an natural model--3-year-old children--to investigate how brain systems respond to external stimulation if their spontaneous rhythms are different in comparison to the spontaneous EEG rhythms in adults. For that purpose we used a combined time and frequency domain approach. The spectral characteristics of the spontaneous EEGs as well as the frequency components of auditory EPs elicited under identical auditory stimulation in 3-year-old children and adults aged 20-22 years were compared. Our observations support the hypothesis for response susceptibility; if in a given frequency channel the spontaneous brain rhythms are missing, they are also absent in the evoked and induced rhythmicities and vice versa: children at 3 years do not create alpha resonance upon sensory stimulation while they do not have developed EEG rhythms in the range of 8-15 Hz. Elicited under identical experimental conditions (auditory stimulation with fixed stimulus parameters) children and adult evoked rhythms differ. It was concluded that the AEPs recorded in 3-year-old children might be regarded mainly as a superposition of rhythmicities in delta and theta ranges. These rhythmicities are prolonged and delayed in comparison to the corresponding rhythms in adults.

Adult↗
PubMed1993

Therapy of vulvar carcinoma.

83 vulvar carcinoma patients were originally treated in the period between 1970 and 1990. 82 patients presented with squamous cell carcinoma. 70% of the patients were in Stage I or II. It was originally possible to operate on 74 of the 83 patients. A simple or partial vulvectomy was applied 17 times. A bilateral inguinal lymph node excision additionally took place in 6 cases. 51 patients were subjected to radical vulvectomy with inguinofemoral lymph node excision. In 13 cases, pelvic lymph node extirpation was also performed. A posterior pelvic exenteration was performed in 6 cases presenting extensive carcinoma involvement of the vulva. In the remaining 9 patients, either it was not possible to operate, or a nonradical operation could be performed. The primary morbidity, consisting of wound healing disturbances and infections, amounted to 50% in our group. We observed lymphedema in 47% of the cases, although it was clinically important in only 10%. We did not have any primary surgical mortality. The 5-year survival rate was 82% in our patients without inguinofemoral lymph node involvement and only 40% in lymph node metastatic cases. The absolute 5-year cure rate was 66%, or 69% corrected. To be able to give increased preference to less invasive methods an improved prevention and clarification procedure for physicians and patients is necessary.

Aged↗
PubMed1992

[Monteggia injuries in athletes. Causes, classification, results].

Monteggia-fractures are serious combination injuries to the forearm. Sport injuries are being increasingly observed; the reason for this, besides the general expansion of mass sports, is the increasing burden of high-performance sports. Monteggia fractures can occur during a fall on an outstretched arm, for example in motor or bicycle sport injuries, but also when falling from gymnastic equipment. Generally, it is easy to diagnose the monteggia injury. Considerable secondary damage could occur from the frequent failure to notice the involved radiohumeral joint. It should be demanded that in case of an uluar fracture the adjoining joints should be x-rayed on two planes in order not to overlook the possibility of a chisel fracture. The different forms of this combination injury, its classification and the results of our own medical bulletins are presented.

Athletic Injuries↗
PubMed1992

Idiopathic hemochromatosis and chromosomal damage.

Spontaneous and radiation-induced chromosome damage in cultured lymphocytes was examined in a pilot study of 11 patients with idiopathic hemochromatosis and matched controls. Increased frequencies of chromosome breaks were found in the patients, both spontaneously and after exposure to ionizing radiation, but the differences between patients and controls were not statistically significant (p greater than 0.05) when individual data were analyzed. When pooled (group) data for patients and controls were compared, significant increases in spontaneous and radiation-induced chromosome breaks were found among the patients. The results suggest that iron overload may lead to chromosome damage in idiopathic hemochromatosis.

Cells, Cultured↗
PubMed1990

Modulation of experimental systemic murine candidosis by intravenous pepstatin.

The effect of intravenous pepstatin-A on systemic candidosis in NWNI mice was investigated. True solutions of the inhibitor proved ineffective due to a very fast clearance. Pepstatin was effective as a crystal suspension (0.69 mg in 0.1 ml saline) which produced serum inhibitory activity for greater than 29 h. From the intravenously applied suspension, pepstatin was taken up predominantly into the liver, no inhibitor being taken up by the kidneys. The suspension was protective if it was injected once before the mice were infected and repeatedly following infection. It was also effective if it was administered concomitantly with the infecting agent and thereafter. The suspension was ineffective if it was only given once before infection, and it proved to be detrimental if it was given only after infection. The results support previous findings (2), suggesting a role of fungal proteinase early in the adherence of Candida to host epithelia. Our results also suggest an inhibition of lysosomal cathepsin-D in vivo by pepstatin, which prohibits a parenteral therapeutic use of nonmodified pepstatin A.

Animals↗
PubMed1989

[Anorexia nervosa masculina--concordance in monozygotic twins].

The case report presents the courses of the disease of an infantile-juvenile masculine monozygotic pair of twins suffering from anorexia nervosa. Beginning, therapy and result turned out differently in spite of a commonly suffered disease. Already the importance of smaller differences in their personality development as well as the merit of the intrageminate dynamic of parts are worked out.

Adolescent↗
PubMed1988

The effect of iron fortification of the diet on clinical iron overload in the general population.

The gene coding for idiopathic hemochromatosis is prevalent in Sweden, the country with the highest iron fortification of food (42%) in the world. We wanted to study if this highly iron-fortified diet had negative effects on the iron situation in carriers of the iron-loading genes. Iron stores averaged 6.7 grams in male homozygotes who were mainly identified through laboratory screening. It was 3.4 grams in female homozygotes. By HLA typing of family members of these homozygous probands, 39 additional homozygotes and 172 heterozygotes were detected. Serum ferritin averaged 620 micrograms/l in 20 male and 168 micrograms/l in 19 female homozygotes in the family screening. Storage iron as measured by serum ferritin concentration was slightly but significantly higher in male heterozygotes than controls (117 micrograms/l versus 87 micrograms/l, p less than 0.02). There was no further increase in serum ferritin concentration with age after 40 years. Heterozygotes showed no clinical signs of iron damage. These findings do not indicate that carriers of the iron-loading genes in Sweden have been adversely affected by the highly iron-fortified diet of the country.

Administration, Oral↗
PubMed1985

Liver affection in iron overload studied with serum ferritin and serum aminotransferases.

Liver dysfunction as measured by S-ALAT activity was present in 72% of patients over 40 years of age with HLA-related iron overload, mainly detected by laboratory screening. Liver dysfunction was correlated to the amount of iron stored (r = 0.54, p less than 0.001). When iron was removed by phlebotomy, liver function returned to normal. S-ALAT activity was closely correlated to serum ferritin concentration (r = 0.73, p less than 0.001). Even a mild iron excess can affect hepatocytes and result in increased levels of ferritin and aminotransferases in serum. Patients with "transaminitis" should be investigated for iron overload.

Adult↗
PubMed1984

Acute cholecystitis and thiazides.

Drugs purchased by a random sample (17 000) of the population of Jämtland county, Sweden, are continuously monitored. Patients who had been admitted to the county's only hospital with acute cholecystitis and who were part of this sample were studied, and controls matched for age and sex were drawn from the sample. The purchase of thiazides and other drugs prescribed to the patients with acute cholecystitis was compared with that of the controls. The estimated relative risk of developing acute cholecystitis in patients who had purchased thiazides in the year before admission to hospital, as compared with those who had not, was 2.1 (95% confidence limit 1.1-3.9). As it has been reliably reported that the use of thiazides is not itself associated with cholelithiasis, the association found between thiazides and cholecystitis suggests that thiazides may increase the risk of acute cholecystitis developing in a patient with gall stones.

Acute Disease↗