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M Moller

Publications and source records attributed to M Moller.

At least 37 records · Page 2Linked to original sources

Localization and diurnal expression of mRNA encoding the beta1-adrenoceptor in the rat pineal gland: an in situ hybridization study.

The rat pinealocyte is stimulated by norepinephrine, which is released from sympathetic nerve fibers innervating the gland. Norepinephrine binds to beta1-adrenoceptors situated on the pinealocyte cell membrane. Ligand binding to these receptors exhibits a diurnal rhythm, with the largest number occurring in the late part of the light phase when the release of norepinephrine is minimal. By using in situ hybridization with a cDNA antisense oligonucleotide probe recognizing mRNA encoding the rat beta1-adrenoceptor, we have demonstrated a stronger hybridization signal in the rat pineal gland than in other brain regions. Cells containing beta1-mRNA are located in the superficial pineal gland, the deep pineal gland, and the pineal stalk. However, the number of receptors varies considerably between the individual pinealocytes. The beta1-mRNA in situ hybridization signal for mRNA encoding the beta1-adrenoceptor of the rat pineal has been quantified over a 24-h period; the strongest signal is found at mid-dark and the weakest signal at mid-light, indicating that the transcriptional regulation of beta1-mRNA synthesis in the rat pineal is diurnal. In addition, maximal receptor protein expression occurs late in the light phase in the rat pineal and is thus considerably delayed compared with its peak mRNA synthesis. This lag time indicates that the beta1-receptor is regulated at the translational or post-translational level. Removal of the sympathetic input to the pineal gland by superior cervical ganglionectomy decreases the beta1-mRNA signal in the gland.

Animals↗

An immunohistochemical study on the postnatal changes in the C-terminal flanking peptide of neuropeptide Y (CPON)--positive nerve fibers in pineal gland of the pig.

Postnatal development of innervation of the porcine pineal gland by C-terminal flanking peptide of neuropeptide Y (CPON)-immunoreactive nerve fibers was examined using the immunohistochemical technique. CPON-positive nerve fibers appeared in the pineal gland of the new-born piglets and formed plexus in the capsula and connective tissue septa of the gland. The nerve terminals branched off from the plexus and penetrated into adjacent parenchyma. The number of nerve fibers immunoreactive to CPON in parenchyma is very low in new-born and 20-day-old piglets. In 7-month-old pigs they created a dense network.

Adrenergic Fibers↗

Tandem duplication of proximal 5q.

A 3.5-year-old boy with a de novo tandem duplication 5q11.1----5q15 is reported. Since the physical stigmata of seven liveborn cases with 5q proximal duplications are variable and inconspicuous, a recognizable syndrome could not be delineated. On the contrary, the associated developmental delay seems to be severe in duplications extending into 5q22 and mild in duplications 5q11----q13.

Child, Preschool↗

[Effect of gene dosage on the glyceraldehyde-3-phosphate dehydrogenase enzyme (GAPD) in partial 12p13.3 pter trisomy].

A family with three brothers presenting 12p trisomy due to an adjacent-1 segregation of a paternal translocation (1;12) (q44;p12.2) is described. The patient's phenotype was compatible with the chromosomal imbalance including the gene dosage effect of the glyceraldehyde-3-phosphate dehydrogenase. The importance of the genetic counseling in these families is stressed.

Abnormalities, Multiple↗

Carbohydrate reactivation of thyroxine 5'-deiodinase (type II) in cultured mouse neuroblastoma cells is dependent upon new protein synthesis.

The T3 concentration in brain predominantly reflects local production from T4 rather than T3 uptake from the circulating pool. We recently demonstrated that rat brain T3 content is increased by glucose feeding compared to chow feeding. One possible mechanism for this effect is an increase in brain T4 5'-deiodinase (5'-D) activity. Our recent preliminary studies of neuroblastoma (NB) cells demonstrate that renewal of RPMI-1640 medium stimulates T4 5'-D type II (NB T4 5'-D II) activity in these cells. The present studies were performed to determine the mechanism of this response. Studies were performed on NB cells supported in thyroid hormone-depleted (deficient) medium. This approach increased NB T4 5'-DII activity 4-fold compared to that in thyroid hormone-replete medium. Medium renewal further stimulated enzyme activity (7- to 9-fold; maximum at 6 h) in each group. The difference between the hypothyroid group and control was sustained over a 24-h period. Subsequent studies demonstrated that glucose (11 mM) was the specific medium ingredient mediating the medium renewal response. A progressive increase in NB T4 5'-DII activity was noted over 8 h during RPMI-1640 salt plus glucose (11 mM) incubation. This was equivalent to the effect of complete medium containing glucose (11 mM). Coincubation with insulin (10(-7)-10(-9) M) did not modify the enzyme response to glucose. In addition, fructose (10 mM) had a similar effect on enzyme activity. Glycerol and essential and nonessential amino acids also modestly increased NB T4 5'-DII activity compared to that in the control group (P less than 0.01). Actinomycin-D (1 microM), cycloheximide (100 microM), and puromycin (100 microM) significantly (P less than 0.001) decreased the glucose effect on T4 5'-DII by 5-, 9-, and 17-fold, respectively, after 6 h of incubation. In addition, puromycin (10-200 microM) inhibited both NB T4 5'-DII activity and [3H]amino acid incorporation during incubation in glucose. There was a significant correlation between these parameters (r = 0.8; P less than 0.001). The enzyme activity decay curves in the glucose-activated and control groups subsequent to puromycin (100 microM) addition at 8 h were parallel. The fractional turnover rate was 13%/h in the controls and 11%/h in the glucose groups. The calculated enzyme production rate was significantly higher (P less than 0.005) in the glucose group compared to that in the control group (17.4 vs. 6.8 fmol/mg protein.h).(ABSTRACT TRUNCATED AT 400 WORDS)

Amino Acids↗

A further 46,XYp- female.

A 24-year-old female with a Swyer syndrome phenotype was found to have a 46,X,del (Y) (p11) karyotype. This observation is consistent with the recently confirmed assignment of the testis-determining master gene to the deletion interval 1A of the Y (Page et al., 1987). Otherwise, it illustrates the etiological heterogeneity of the Swyer phenotype and allows to emphasize the de novo origin of XYp-females.

Chromosome Deletion↗

Constitutional del(5)(q23.3q31.1).

A 4-month-old male infant with muscular hypotonia, growth and psychomotor retardation, large low-set ears, hypoplastic genitalia, right hip luxation and bilateral equinovarus, was found to have a constitutional 46,XY,del(5)(q23.3q31.1) karyotype. From the comparison with 12 similar cases, a rather characteristic clinical phenotype emerges.

Abnormalities, Multiple↗

Ovarian dysgenesis due to an idic(X)(q2803).

A 17-year-old female patient with gonadal dysgenesis but no other turnerian features was found to have a 46,X,idic(X)(pter----q2803:q2803----pter) karyotype in her lymphocytes. Replication of the rearranged X was consistently late and symmetrical. It is postulated that the ovarian dysgenesis usually seen in nonmosaic carriers of Xq;Xq terminal rearrangements may be secondary to a nonreactivation of the abnormal chromosome before meiosis.

Adolescent↗

inv(5)(p13q13) in a four generation pedigree.

A 4 1/2 years old boy was found to have hypoplasia of the pectoralis major right muscle and a karyotype 46,XY,inv(5)(p13q13)mat. This inversion, probably independent of the boy's malformation, was present in at least four generations and it seems neither to impair fertility nor to yield viable recombinants.

Child, Preschool↗

Trisomy 6qter resulting from a familial (6;10) (q23;q26) translocation.

An infant deceased at 2 months of age was found to have a 46,XY,-10, +der(10),t (6;10) (q23;q26) mat karyotype. Since the clinical findings were similar to those of the trisomy 6qter syndrome, the present observation agrees with the assignment of the 6q23----qter segment as the pathogenetic determiner of this entity.

Chromosome Banding↗

Monosomy 13q32.3----qter: report of two cases.

Two unrelated patients with monosomy 13q32.3----qter are reported. Comparison with six similar cases previously published indicates that the craniofacial dysmorphism of the 13qter monosomy syndrome is related to band 13q34, the thumb hypoplasia to band 13q32, and an apparently different phenotype to band 13q33. Coagulation deficiency appears to be non-specific in monosomy 13qter.

Child, Preschool↗

46,XX,-12,+der(12),rcp(3;12)(p25.1;p13.31)pat karyotype in a girl. Probable subregional assignment of glyceraldehyde-3-phosphate dehydrogenase locus to 12p13.1----p13.31 by exclusion mapping.

A female infant with partial trisomy 3p and a terminal deletion 12p, due to a paternal (3;12)(p25.1;p13.31) translocation is described. Normal glyceraldehyde-3-phosphate (GAPD) activity in the proposita tentatively excludes GAPD locus from the deleted segment. Therefore, the region for this locus is reduced to 12p13.1----p13.31.

Abnormalities, Multiple↗

Trisomy 7p due to a mosaic normal/dir dup(7)(p13----p22). Syndrome delineation, critical segment assignment, and a comment on duplications.

A 4 4/12 year-old girl with a peculiar phenotype due to a 46,XX/46,XX, dir dup(7)(p1300----p2200) karyotype is described. The comparison with about ten similar cases permitted a better delineation of the 7p trisomy syndrome and the assignment of the band 7p21 as the critical one. Mechanisms for the origin of homogeneous and mosaic duplications, including one model based on a meiotic half chromatid duplication, are discussed.

Abnormalities, Multiple↗

Familial inv(2) (p2300q11.2).

A hitherto undescribed inv(2) (p2300q11.2) was found in 2 generations of a family ascertained through a holoprosencephalic liveborn boy with normal karyotype. This inversion, quite probably not related to the child malformations, does not seem neither impair reproductive fitness nor to yield viable recombination aneusomies.

Chromosome Banding↗