THE BASE COMPOSITION OF NUCLEIC ACIDS IN CHROMOSOMES, PUFFS, NUCLEOLI, AND CYTOPLASM OF CHIRONOMUS SALIVARY GLAND CELLS

The base composition of RNA from individually isolated giant chromosomes, puffed chromosome segments, nucleoli, and samples of cytoplasm from Chironomus salivary gland cells was determined by microelectrophoresis. Data on the adenine: guanine quotient of the chromosomal DNA were also obtained. The results show that: 1) Chromosomal, nucleolar, and cytoplasmic RNA's differ significantly from each other in base composition. 2) Nucleolar and cytoplasmic RNA's, in spite of the difference, show great similarities with regard to the base composition and are both rich in adenine and uracil. 3) The RNA extracted from chromosome I differs significantly from the RNA's extracted from different segments of chromosome IV, and the latter differ significantly from each other. 4) The values for the RNA: DNA quotients of chromosome segments parallel the development of synthetically active genes, so-called Balbiani rings. 5) The chromosomal RNA does not show a base symmetry in any of the investigated cases, nor is the content of guanine + cytosine the same as that for DNA. The first of these two facts excludes the possibility that the chromosomal RNA is a complete copy of both strands of the chromosomal DNA. In spite of the difference in guanine + cytosine content between the two nucleic acids the RNA may still partly or completely be a single strand copy depending upon how representative the DNA values are for the synthetically active DNA.

The genetics of dopa decarboxylase in Drosophila melanogaster. IV. The genetics and cytology of the 37B10-37D1 region

Of 204 mutations located in the 8-12 band Df(2L)130 region, 37B9-C1,2;37D1-2, 199 have been assigned to twelve lethal genes and one visible gene (hook). The 13 genes are not evenly distributed. Twelve, (possibly all thirteen) are in the seven band region 37B10-C4 giving a gene-to-band ratio of almost two. Only one gene, 1(2)37Cf, may be in the four band region 37C5-7, and none are localized in band 37D1. In situ hybridization places the dopa decarboxylase structural gene, Ddc, in or very close to band 37C1,2 (Hirsh and Davidson, 1981). The chi methyl dopa hypersensitive gene, 1(2) and, is 0.002 map units distal to Ddc. Df(2L)VA17, 37C1,2; 37F5-38A1 may actually break in the 37C1,2 singlet. It places six genes, hook, 1(2) and, and four lethal genes, in a maximum of five bands, 37B10, 11, 12, 13 and perhaps part of the 37C1,2 singlet and localizes six genes, Ddc plus five lethal genes, in a maximum of three bands; probably part of the 37C1,2 singlet plus bands, C3, and C4. Wild type activity of five of twelve lethal genes is necessary for female fertility. --Band 37C5 puffs at the time of pupariation; Puff Stages 8-10. Twelve of eighteen alleles of 1(2)37Cf have been examined as heterozygotes over CyO and none affect the appearance of a homozygous 37C5 puff. --Of the 204 mutations considered here only one Ddcpl, affects the function of more than one gene. It eliminates Ddc+ and 1(2)37Ca+ function and at 30 degrees C reduces 1(2)37Ce+ function. It is not a deficiency but could be a polar mutant.

A repetitive DNA sequence associated with the centromeres of Chironomus pallidivittatus

A clone containing centromere-associated DNA from Chironomus pallidivittatus was obtained by microdissection-microcloning. It hybridizes to the centromeric end of one chromosome and exclusively to regions in the three remaining, metacentric chromosomes to which centromeres have previously been localized on cytological grounds. In the metacentric positions the hybridization can be assigned to thin bands. The clone contains 155bp tandem repeats and short flanking regions represented in all of the centromeres. Titration experiments show that the four centromeres together contain 200kb of 155bp repeat per genome. In a line of tissue culture cells the amounts are increased by a factor 1.5-2, resulting in proportionately extended arrays of tandem repeats. Each repeat contains two invertrepeats surrounding a region containing only AT base pairs, a feature with some similarity to functionally essential elements in the Saccharomyces cerevisiae centromere.

Homology of Balbiani ring DNA in two closely related Chironomus species

Cytogenetic analysis indicates that Balbiani Ring 2 (BR 2) in the two sibling species Chironomus tentans and Chironomus pallidivittatus arises from identifically banded segments in the salivary gland polytene chromosomes, although chromosomal rearrangements have occurred. In situ hybridization of BR 2 RNA to the polytene chromosomes of each individual species, as well as their F1 hybrids, reveals that the repetitious BR 2 DNA in the two species has, within the limits of the technique, retained identity of nucleotide sequences and degree of repetition. The DNA of the naturally expressed BR 1 and BR 3 in both species and that ot the galactose induced BR 6 in C. pallidivittatus did not hybridize with BR 2 RNA, indicating that these BR's are different from BR 2 with regard to sequence content.

Acute myocardial infarction with cardiogenic shock on admission: incidence, prognostic implications, and current treatment strategies. Results from "the 60-Minutes Myocardial Infarction Project". ALKK ("Arbeitsgemeinschaft leitender Krankenhauskardiologen") Study Group

Little data exist about current treatment strategies the efficacy of thrombolytic therapy and outcome of patients with acute myocardial infarction (AMI) presenting in cardiogenic shock (CS). Data from the German multicenter "60 Minutes Myocardial Infarction Project" were used to analyze a large number of patients with AMI and CS on admission and to compare those to patients without CS. Between July 1993 and September 1994 a total of 7,085 patients with AMI were registered. Out of these, 179 patients (2.5%) presented in CS (systolic blood pressure < 100 and heart rate > 100/min, resuscitated patients were excluded). Patients in CS were significantly older than patients without CS. Their in-hospital mortality was 47.1% compared with 12.4% in patients without CS (p = 0.001). The prevalence of the following clinical parameters was significantly higher in patients with CS than in those without CS: bundle branch block, prior MI, and a non-diagnostic ECG (all p < 0.05). Thrombolytic therapy was used in 36.3% of patients in CS and in 50.8% of those without CS (p = 0.001). The in-hospital mortality in patients with CS receiving thrombolytic therapy was significantly lower than in patients with CS who did not receive thrombolytic agents (33.3% versus 55.1%; p = 0.006). In daily clinical practice in Germany thrombolytic treatment is used in only 36.3% of patients with AMI presenting in CS on admission. The use of thrombolysis in CS on admission is associated with a lower in-hospital mortality.

[New cases of botulism after intragastric injection of botulinum toxin]

Two female patients presented to our clinic shortly after one another with visual disturbances, double vision, swallowing difficulties and shortness of breath, a few days after an intragastric injection of botulinum toxin in a clinic in Turkey.The physical examination was unremarkable except for signs of respiratory insufficiency with increased respiratory rate and shortness of breath, especially when lying down; no clear neurological symptoms were found. Imaging showed reduced diaphragmatic mobility. Blood gas analyses showed hypoxemic respiratory insufficiency.The patients were observed as inpatients for a few days without specific therapy and were discharged with regressing symptoms.In March 2023, the Robert Koch Institute, the European Centre for Disease Prevention and Control and the WHO published a report on 87 patients who had received intragastric injections of botulinum toxin in 2 Turkish hospitals with the aim of losing weight and subsequently have developed symptoms of botulism. The current cases presented here draw further attention to the problems of the procedure that is still being carried out and to the risks of botulism.

[Ingestion of a rodenticide with subsequent prolonged coagulopathy]

BACKGROUND

Free-selling rodenticides contain highly potent and long-acting coumarins that may cause severe and prolonged coagulopathies.

CASE REPORT

A 46-year-old male was admitted after accidental ingestion of a rodenticide with spontaneous hematomas and a nonmeasurable prothrombin time (International Normalized Ratio [INR]). He had a prolonged coagulopathy and required high doses of vitamin K(1) to normalize the prothrombin time. A dose reduction of vitamin K(1) was followed by a new rise in the INR.

CONCLUSION

In cases of coagulopathy and suspicion of an intoxication with anticoagulants, an ingestion of rodenticides containing highly potent coumarins should be taken into account. Intoxications with these "superwarfarins" require high doses of vitamin K(1) given for several weeks.