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Biomedical subjects

R Koch

Publications and source records attributed to R Koch.

At least 181 records · Page 10Linked to original sources
PubMed1991

Intellectual development in 12-year-old children treated for phenylketonuria.

Intelligence and achievement test scores were evaluated for 95 12-year-old children with phenylketonuria who had begun dietary therapy during the neonatal period. Dietary control of blood phenylalanine below 900 mumol/L was maintained beyond age 10 years in 23 children; 72 others had blood phenylalanine persistently above that level at ages ranging from 18 months to 10 years. Test scores at age 12 years were negatively correlated with the age at initiation of diet and with blood phenylalanine levels from ages 4 to 10 years, and positively correlated with parent IQ scores and the age at loss of dietary control. Children who maintained phenylalanine levels below 900 mumol/L beyond age 10 years showed no deficits in test scores, except for arithmetic, the scores of which declined between ages 6 and 12 years in 90% of the children in this study. These data strongly support a recommendation that dietary restriction of phenylalanine should be maintained through adolescence.

Child↗
PubMed1991

N-acetylglutamate synthetase deficiency: clinical and laboratory observations.

Two male siblings presented in the first 6 weeks of life with emesis, diarrhoea, metabolic acidosis and lethargy. A male sibling had previously died at 14 months of age from liver failure of unknown aetiology. Both of the current cases had mild hyperammonaemia with normal orotic acid, organic acid and argininosuccinic acid levels. Citrulline and arginine levels were normal or mildly decreased. One of the brothers was biopsied and had no detectable N-acetylglutamate synthetase activity and normal values for other enzymes of the urea cycle in liver. Treatment with a low-protein diet and sodium benzoate/sodium phenylacetate resulted in near normal blood ammonia levels, except during viral illness. Subsequent neurological development has been normal to mildly delayed. These patients differ from those previously described with N-acetylglutamate synthetase deficiency in that their presentation and subsequent course were relatively benign.

Acetyltransferases↗
PubMed1991

Subjective appraisal of orthodontic practices. An investigation into perceived practice characteristics associated with patient and parent treatment satisfaction.

Based on a comprehensive in-practice questionnaire survey among 254 school-age patients and their parents, the subjective perception and evaluation of orthodontic care was investigated. By means of refined statistical analysis, three types of practice showing significantly distinct image profiles were identified. Likewise, the set of discriminating variables was reduced and assigned to the fundamental concepts of 'interpersonal satisfaction' and 'perceived efficacy' which appeared to play a crucial part in the crystallization of both patients' and parents' contentedness with the treatment received. To take account of the interdependence of instrumental and social factors, a model of perceived practice similarity is suggested; its significance regarding treatment decisions and future research efforts is pointed out.

Adolescent↗
PubMed1991

[The symptomatic therapy of cervical hard-substance defects with dentin-adhesive-composite systems].

For covering of hypersensitive, morphologically disturbed and non-esthetic cervical (wedge-shaped) defects of hard dental tissues, dentine adhesive composite systems are suitable for a careful and less invasive preparation. Presumption is a smooth and at probing hard-touched defect surface. A clinical 2 year study (15 patients with 143 cervical lesions) using 5 different dentine adhesive composite systems resulted in superiority of the hybrid composite P-30 in view of low filling losses (after 1 year: 1 of 28 fillings after 2 years: 2 of 27 fillings), the acceptable bond zone morphology (after 1 and 2 years clinical intact bond zones), and a constant volume behaviour (after 1 and 2 years no clinical changes of volume). The micromorphological evaluation correlated in a lot of cases with the clinical findings after 2 years. It has to be expected that improved dentine adhesive composite systems together with changed setting mechanisms of dentine adhesives will be able to eliminate filling losses in the treated indication.

Composite Resins↗
PubMed1991

[Temperature-controlled bipolar electrocoagulation].

The safety of electrocoagulation for laparoscopic surgery has been greatly improved by the introduction of the bipolar coagulation technique. But complications caused by coagulation, especially by the overheated forceps, are still reported. In order to reduce those complications, a temperature controlled bicoagulation system was developed. This system allows coagulation with lower temperatures which can be kept constant during the coagulation process. In experiments with human fallopian tubes obtained by adnexectomy and rabbit uterine horns it is shown that those lower temperatures are sufficient for homogeneous coagulation. On line monitoring of the temperature during coagulation provides the surgeon with the possibility of directly controlling the actual temperature at the tip of the forceps. The temperature curves can easily be stored in order to be able to demonstrate the particular coagulation process even after years.

Animals↗
PubMed1991

Mental development in Down syndrome mosaicism.

Serial assessments of mental status of 30 subjects with Down syndrome mosaicism were compared with those of 30 subjects with trisomy 21 Down syndrome. The samples were matched for age, sex, and parental socioeconomic background. The mean IQ level of the mosaic Down syndrome group was significantly higher than that of the trisomy 21 group. Many subjects with mosaicism showed better verbal abilities, and some also demonstrated normal visual-perceptual skills in paper- and-pencil tasks. Children with Down syndrome with IQs over 60 at 5 years of age and with relatively normal speech can be viewed as a suspected case of mosaicism. Chromosomal analysis is mandatory to confirm or disprove this diagnosis.

Adolescent↗
PubMed1991

Macroscopic and histologic study to differentiate large glands and bulbi in the perianal body region of the male gray short-tailed opossum, Monodelphis domestica.

On either side of the cloaca of the male Monodelphis domestica, there is a large pack of globular structures lying between the external skin and the ischial arch. The structures within each of these bilateral complexes can be classified into three groups. Group 1 comprises different kinds of glands. There are two large glands, "Paraproctic glands" according to Schaffer (1940), whose spacious cavity is bounded by a secretory epithelium. The secretion is holocrine in a way that cells are shed into the wide cavity. Further, there are two large bodies built of sebaceous acini around a central cavity. The inner surface of the cavity is a squamous stratified epithelium. A peripheral layer of secretory tubuli completes the structure's wall. The bodies are referred to as "Circumanal glands" according to Schaffer (1940). Their excretory ducts end into the cloaca. Group 2 is located between the glands of group 1 and group 3. Macroscopically, the structures of this group are easily mistaken as glands, however, histologically they are identified as a bilateral bulb of the corpus spongiosum, and as a bilateral bulb of the crus of the corpus cavernosum penis. Group 3 includes three different glands that end into a bilateral expansion of the urethra. These accessory genital glands are very distinct due to the histologic characteristics of their secretory epithelium.

Anal Canal↗
PubMed1991

[The hypophysis of Monodelphis domestica (Marsupialia): the state of organ development and cell differentiation in the adenohypophysis on different days post partum].

In the newborn gray short-tailed opossum, Monodelphis domestica, the fusion of the neurohypophysis and adenohypophysis has not finished. A compression of the adenohypophyseal vesicle is exerted by the neurohypophysis. The latter, as can be seen in a 12-day old specimen, finally, will be almost completely wrapped into the adenohypophysis. The adenohypophysis of the newborn and early pouch-young shows substantial growing on the basis of mitoses mainly in the pars intermedia, but in the pars distalis, too. Cytodifferentiation in the newborn, light microscopically, is indicated by an increasing heterogeneity of cell morphology which is most obvious in the cranial and caudal regions of the median sections. Electron microscopically, the presence of small quantities of granules as well as small quantities of golgi membranes and ribosomal endoplasmic reticulum, respectively, gives evidence of a beginning synthesis activity in the newborn.

Animals↗
PubMed1991

[An unusual case of chronic fibrosing endometritis and mucometra in a Watusi cow (Bos primigenius f. taurus) with uterine foreign bodies].

Genital organs, ureter, urinary bladder, and blood were collected from a 12 year old watusi cow which never exhibited estrous behaviour. Post-mortem findings and hormone assays, however, indicated the incidence of recent estrous cycles. The animal showed a chronic panmetritis, retained fetal membranes or fetal residues, an infected mucometra with cystic glandular hyperplasia, and a leiomyoma. Tubular genitalia, ureter, and urinary bladder exhibited subacute inflammation.

Animals↗
PubMed1990

Extrapyramidal symptoms in neuroleptic recipients.

Adverse drug reactions (ADRs) in psychiatric therapy were continuously assessed in the AMUP study (AMUP = Arzneimittelüberwachung in der Psychiatrie (drug surveillance in psychiatry] conducted at two psychiatric university departments in the F.R.G. The Intensive Drug Monitoring (IDM) method was used to monitor 1107 patients, 754 of whom received neuroleptics (NLs). As is the rule in clinical psychiatric practice, polypharmacy was frequent, with combinations of two neuroleptics and combinations of a neuroleptic and an antiparkinson drug ranking first and second, respectively. Extrapyramidal motor symptoms (EPMS) were observed in 35% of the NL patients. In most cases they required a change in medication, usually addition of an antiparkinson drug. In about one quarter of all EPMS cases, withdrawal of the imputed NL was necessary. Parkinsonism was the most frequent single symptom, followed by acute dystonia and akathisia. Differences in EPMS rates between the two most frequently used neuroleptics, haloperidol, a high-potency butyrophenone, and perazine, a medium-potency phenothiazine, were distinct. EPMS were observed with haloperidol in 56% and attributed to haloperidol alone in 92% of these cases. With perazine, an EMPS occurred at a rate of only 14%, and in 37% of the cases EMPS were attributable to perazine in combination with other NLs. Age, sex, diagnosis and dosage of administered NLs were closely interrelated. For instance, NL patients over 60 years of age were almost exclusively female, the majority of them being endogenous depressives, whereas in younger patients the diagnosis of schizophrenia prevailed. Therefore, analysis of potential risk factors for development of EPMS must simultaneously include diagnosis, sex and age as well as concomitant physical disease, duration and dosage of all drugs administered before development of EPMS. However, the small case numbers in some subgroups, as we found them in this study based on everyday clinical practice, will probably be a limiting factor in such multivariate analyses.

Acute Disease↗
PubMed1990

The Zurich Study. IX. Panic disorder and sporadic panic: symptoms, diagnosis, prevalence, and overlap with depression.

The purpose of the present epidemiological study is to investigate and describe panic disorder and sporadic panic attacks among a cohort of young adults, aged 28 years, from the Canton of Zurich in Switzerland. Both DSM-III panic disorder and sporadic panic are characterized by frequent symptoms of somatic anxiety and tension, as well as by frequent symptoms of depressed mood and low vitality. Sporadic panic is more prevalent than panic disorder and shows a greater excess of females over males. The association with depressions (major depression and recurrent brief depression) is similarly high for both types of panic syndromes, while the association with other anxiety disorders is negligible. Several indicators suggest a marked similarity between sporadic panic and DSM-III panic disorder. More impressive differences were observed between subjects with panic disorder alone and subjects with comorbidity of panic and depression. For the latter group, the SCL-90R scores indicated higher severity. Comparison of the scores of life events, conflicts, self-esteem, and the number of chronic problems in childhood suggests a more specific nosological pattern for subjects with panic and depression as compared with those with panic alone.

Adult↗
PubMed1990

A preliminary report of the collaborative study of maternal phenylketonuria in the United States and Canada.

The Maternal Phenylketonuria Collaborative Study (MPKUCS), encompassing all the United States and provinces of Canada, is a prospective, longitudinal investigation designed to ascertain the efficacy of phenylalanine-restricted therapy in protecting the fetus from high maternal phenylalanine concentrations in women with hyperphenylalaninaemia. Preliminary findings are reported for 147 pregnancies for whom the recommended therapeutic range of blood phenylalanine was 120-360 mumols/L. Sixty-three pregnancies had complete data for analysis. Dietary control was attempted prior to conception in 10 out of 63 women. Significant negative correlations were noted in length, weight and head circumference and blood phenylalanine concentrations during pregnancy. Average reported phenylalanine levels by trimester for 63 hyperphenylalaninaemic pregnancies resulting in live births revealed that no group requiring treatment achieved levels below 360 mumols/L until the third trimester. Median birth measurement percentiles revealed that all groups studied generally had smaller head size compared with birth length and weight. Those started on diet after the first trimester achieved a head circumference below the 10th percentile. The implication of small head circumference for subsequent intellectual development is unclear at this time. Furthermore, the study must evaluate more offspring of women having optimal preconception and pregnancy restriction of phenylalanine.

Canada↗
PubMed1990

[The topography of the abdominal organs of Monodelphis domestica (Marsupialia)].

30 adult animals (14 females, 16 males) were studied macroscopically. The main findings are as follows: 1. The intestine is without striking macroscopic features that characterize the different parts of it. A variation of position of ileum, cecum, and colon, respectively, is due to the length of their mesenteries. 2. In adult males, the intestines are displaced from their position in the caudal part of the abdomen by the urethra (the urethral diameter is even wider than that of the gut, because the wall contains masses of prostatic glandular tissue). 3. The liver is clearly divided into lobes, however, there is no notch between the quadrate lobe and the left medial lobe. The falciform ligament is regarded as the border-line between these lobes, while the gall bladder separates the quadrate lobe from the right medial lobe. 4. The spleen lies almost entirely caudal to the costal arch. It extends dorsally between the stomach and the left kidney. Along the body wall, it reaches the ventral median line and shows even a slight orientation towards the xiphoid cartilage. 5. The greater omentum may extend to the cranial end to the urinary bladder. It is extremely thin and therefore hardly visible. 6. In females, subperitoneal fat may extend from the caudo-dorsal body wall along the lateral walls down to ventral regions, in some cases even occupying a considerable part of the caudo-ventral abdomen.

Animals↗