Seasonal characteristics of flood regimes across the Alpine-Carpathian range

The aim of this paper is to analyse the differences in the long-term regimes of extreme precipitation and floods across the Alpine-Carpathian range using seasonality indices and atmospheric circulation patterns to understand the main flood-producing processes. This is supported by cluster analyses to identify areas of similar flood processes, both in terms of precipitation forcing and catchment processes. The results allow to isolate regions of similar flood generation processes including southerly versus westerly circulation patterns, effects of soil moisture seasonality due to evaporation and effects of soil moisture seasonality due to snow melt. In many regions of the Alpine-Carpathian range, there is a distinct shift in flood generating processes with flood magnitude as evidenced by a shift from summer to autumn floods. It is argued that the synoptic approach proposed here is valuable in both flood analysis and flood estimation.

Molecular basis for the regulation of cell fate by the lethal (2) giant larvae tumour suppressor gene of Drosophila melanogaster

Tumour suppressor genes act as recessive determinants of cancer. Their function is required for normal cell growth and differentiation during development. When both alleles of these developmental genes are inactivated, cell growth becomes unrestricted. In Drosophila, a series of genes have been identified which when mutated produce tissue-specific tumours. Of these the lethal(2)giant larvae (l(2)gl) gene is the best studied. Homozygous l(2)gl mutations cause the development of malignant tumours in the brain and the imaginal discs. Genomic DNA from the l(2)gl locus has been cloned, introduced back into l(2)gl mutant animals by P-element-mediated transformation and shown to restore normal development. The nucleotide sequence of the l(2)gl gene (13.1 kb) has been determined, as well as the sequences of the two classes of transcripts. These transcripts encode two polypeptides of 127 kDa and 78 kDa, respectively. Both proteins have been immunologically identified. Analyses of the spatial distribution of both l(2)gl transcripts and proteins revealed that during early embryogenesis the l(2)gl gene is uniformly expressed in all cells and tissues. In late embryos, the l(2)gl expression becomes gradually restricted to tissues presenting no morphological or neoplastic alteration in the mutant animals. Further mosaic experiments pointed out that the critical period for the establishment of tumorigenesis is limited to early embryogenesis at a time when the l(2)gl expression is most intense in all cells.

Pregnancy-associated hypertension in Maputo. A study on maternal characteristics and perinatal outcome in 1275 consecutive cases

A total of 1275 consecutive cases of pregnancy-associated hypertension were registered in the Maputo Central Hospital (corresponding to 2.9% of a total of 43,794 city parturients). In the hypertensive and in the reference populations the following prevalence figures were registered, respectively: age below 25 years, 52% and 23% (P < 0.0005); nulliparity, 33% and 19% (P < 0.0005); twin pregnancies, 3.9% and 1.7% (P < 0.0005); stillbirths, 5.7% and 2.3% (P < 0.0005); and low birthweight (LBW), 22.9% and 10.7% (P < 0.0005). In the hypertensive population the prevalence of LBW newborns was 20.1% in the liveborn group, while it was 68.4% in the stillborn group (P < 0.0005). In the ongoing perinatal audit it was found useful to review hypertensive women separately, in order to assess current routines in cases of pregnancy hypertension.

Brainstem response in cerebellopontine angle tumors

OBJECTIVE

To evaluate the auditory brainstem response (ABR) findings in cerebellopontine angle (CPA) tumors and focus on those with normal ABR results.

STUDY DESIGN

This was a retrospective evaluation of ABR findings. All subjects with diagnosed CPA tumors who were referred for treatment were included.

PATIENTS

All 309 patients with radiographically confirmed (computed tomography or magnetic resonance imaging [MRI]) CPA tumors (153 before 1993 and 156 after 1993).

INTERVENTION

All patients underwent complete audiologic examination, electronystagmography, ABR testing, and ipsilateral transtympanic electrocochleography. All tumors were histologically confirmed.

MAIN OUTCOME MEASURES

The patients were categorized according to ABR results (normal or pathologic findings or no response); according to histology (vestibular schwannomas or meningiomas); and according to tumor size by MRI (small, up to 15 mm; medium, 16-25 mm; large, 26-40 mm; and very large, over 40 mm).

RESULTS

Normal ABR results were found in 18.4%; pathologic ABR results in 31.4%; and no response in 50.2%. Small vestibular schwannomas (under 15 mm) showed a higher incidence of normal ABR results (41.7%). CPA tumors with normal ABR results (n = 57) caused no hearing loss (n = 12), symmetrical hearing loss (n = 11), or ipsilateral hearing loss with Short Increment Sensitivity Index 100% and normal acoustic reflex (cochlear deafness, n = 34). Caloric response was normal in 59.7% of these tumors.

CONCLUSION

Because validation of ABR as screening for acoustic tumors is based on diagnosed tumors, and because MRI allows detection of very small tumors, the incidence of normal ABR increases and its sensitivity would be expected to decrease. ABR is not sufficient for early detection of small CPA tumors.

[Alcohol, occupational accidents and their sequelae]

Alcohol is a considerably more important risk factor for non occupational accidents than for occupational accidents, but somatic and psychosocial consequences of chronic alcohol consumption can also have very negative influences on the course of healing and professional rehabilitation. Three cases illustrate the importance of the primary and secondary prevention. They did charge the workers' compensation account of the companies involved with more than one million francs, with corresponding increases in workers' compensation premiums.

Interactive query workstation: a demonstration of the practical use of UMLS knowledge sources

The Interactive Query Workstation (IQW) has been developed to provide clinicians with a uniform program interface for retrieving medical-related information from various computer-based information resources. These resources can vary in content (bibliographic databases, drug information, general medical text databases), function (article retrieval, differential diagnosis, drug interaction detection, or drug dosage and administration information), and media formats (local hard disk, CD-ROM, local area network, or distant telecommunication link). IQW allows modular addition of new resources as well as extension of previously installed resources. The National Library of Medicine's three Unified Medical Language System (UMLS) Knowledge Sources, the Metathesaurus (Meta), the Semantic Network, and the Information Sources Map (ISM) have been incorporated into many aspects of IQW. Meta provides information about medical terminology and aids IQW in isolating the basic concepts from a clinician's question. The Semantic Network provides information about the categorization of concepts and possible relations between concepts. It also assists IQW in determining which queries are appropriate for a set of concepts contained in the clinician's question. The ISM provides information about the content available from a computer-based resources and aids IQW in selecting an appropriate resource from which to collect information. The computer-based resource selection is performed without user intervention. This interactive demonstration shows an environment which increases the accessibility of medical information to clinicians by utilizing the three UMLS Knowledge Sources.

Transcriptional and translational regulation of the expression of the l(2)gl tumor suppressor gene of Drosophila melanogaster

By structural, biochemical and molecular genetic analyses, we have investigated the different mechanisms that control the expression of the lethal(2) giant larvae gene, a tumor suppressor gene of Drosophila melanogaster. Transcription of the l(2)gl gene is controlled by two highly identical promoters that result from the duplication of the 2.8 kb proximal portion of the gene. These two repeats are 96% homologous. Reverse genetic analysis has shown that each promoter can drive gene expression. In addition to the promoters, both repeats express two or three exons according to the pattern of splicing. The most distal exon in the second repeat is required because it contains the ATG initiating codon at the beginning of the open reading frame. The 3' untranslated region appears to contain motifs that specifically destabilize the transcript. Deletion of this region results in the formation of more stable mRNAs. The l(2)gl gene is characterized by an unusual codon usage that may reflect an enhanced translation efficiency by moderating the strength of pairing between codons and anticodons and may therefore increase the expressivity of this gene. Analysis of the spatio-temporal expression of the l(2)gl transcripts and proteins has shown that transcripts and proteins are produced ubiquitously during early embryogenesis, at a time when expression of the gene is required for preventing tumorigenesis. In the second half of embryogenesis, l(2)gl expression becomes restricted to tissues that do not show any phenotypic alteration in mutant animals. The l(2)gl protein exhibits two distinct intracellular localizations. It is preferentially found free in the cytoplasm but can become associated with the inner face of the plasma membrane where it is restricted to domains facing contiguous cells. In particular, the l(2)gl protein is absent from the basal and apical domains of the plasma membrane. The aim of the current research is directed towards understanding the functional relevance of the l(2)gl protein binding to the plasma membrane and its role in the control of cell proliferation and differentiation.

Molecular action of the l(2)gl tumor suppressor gene of Drosophila melanogaster

Tumor suppressor genes act as recessive determinants of cancer. These genes contribute to the normal phenotype and are required for regulating cell growth and differentiation during development. Inactivation of tumor suppressor genes leads to an unrestricted pattern of growth in specific cell types. In Drosophila, a series of genes have been identified that cause tissue-specific tumors after mutation. Of these, the lethal(2)giant larvae (l(2)gl) gene is the best studied. Homozygous l(2)gl mutations cause the development of malignant tumors in the brain and the imaginal discs. Genomic DNA from the l(2)gl locus has been cloned, introduced back into the genome of l(2)gl-deficient animals, and shown to reinstate normal development. The nucleotide sequence of the l(2)gl gene has been determined, as well as the sequences of two classes of transcripts. Analysis of the spatial distribution of both l(2)gl transcripts and proteins revealed that during early embryogenesis the l(2)gl gene is uniformly expressed in all cells and tissues. In late embryos, the l(2)gl expression becomes gradually restricted to tissues presenting no morphological or neoplastic alteration in the mutant animals. Further mosaic experiments revealed that l(2)gl gene loss can cause three distinct phenotypes: neoplastic transformation, abnormal differentiation, and normal development. These phenotypes depend upon the extent of gene activity in the stem cells prior to the formation of l(2)gl- clones. These analyses indicate that the critical period for the establishment of tumorigenesis occurs during early embryogenesis at a time when the l(2)gl expression is most intense in all cells.

Cardiac consequences of renal transplantation: changes in left ventricular morphology and function

To characterize changes in left ventricular morphology and function associated with renal transplantation, noninvasive cardiac evaluations were performed in 41 adults at the time of surgery and at follow-up. At the time of transplantation, 36 patients had undergone hemodialysis through a fistula for 2.3 +/- 2.5 years (mean +/- SD); their hematocrit level was 26 +/- 6% and systolic blood pressure was 151 +/- 19 mm Hg. Perioperatively, left ventricular hypertrophy was present in 93% of patients by echocardiography, but in only 37% by electrocardiography. Abnormal left ventricular diastolic function was present in 67% of patients and indicated a high risk for perioperative pulmonary edema. At follow-up (1.5 +/- 1.4 years), mean hematocrit level increased to 39 +/- 7%, systolic blood pressure decreased to 132 +/- 14 mm Hg and spontaneous closure of the fistula occurred in 13 patients. Left ventricular mass by echocardiography decreased from 237 +/- 66 to 182 +/- 47 g (p less than 0.001), a decrease of 23%. Left ventricular volumes and cardiac index also decreased significantly, reflecting the rapid resolution of a pretransplant high output state. Despite proportionate regression of left ventricular hypertrophy within months of transplantation, diastolic function did not improve. The significant regression of left ventricular hypertrophy that occurs after renal transplantation may help explain the improved cardiovascular survival of patients with a renal transplant over that of patients on long-term dialysis.

Growth characteristics of anaerobically treated early and late S-period of Ehrlich ascites tumor cells after reaeration

Utilizing centrifugal elutriation, early and late S-phase cells were separated from 4, 8 and 12 h anaerobically cultured Ehrlich Ascites tumor cells strain Karzel. The cytokinetic properties of these fractions after reaeration were studied by flow cytometry and the BrdU-H 33258-technique of flow cytometry. After a 4 h period of anaerobiosis, growth of early S-phase cells is not changed, 8 h deprivation of oxygen causes a delay of cell cycle progression, while the main fraction of 12 h anaerobically treated early S-populations did not divide after reaeration within 24 h. In comparison to early S-phase cells the cell cycle progression of the main fraction of late S-period is accelerated after a 4 h exclusion of oxygen. A fraction of 8 h anaerobically pretreated late S-cells continues to cycle, but a considerable number reinitiates DNA synthesis without preceeding division. Cells with DNA content up to 8 c are detected by flow cytometry. 12 h anaerobically cultured late S-cells do not divide after reaeration, a large number of these cells starts again to synthesize DNA. A considerable part of tetraploid cells retain viability, divide and enter a new cell cycle, another part of the cells disintegrates.

Growth characteristics of anaerobically treated Ehrlich ascites tumor cells after reaeration as studied by combination of flow cytometry and centrifugal elutriation

Centrifugal elutriation was applied to separate into the cell compartments asynchronous Ehrlich ascites cells grown under different culture conditions. The cytokinetic properties of the recultivated fractions were studied by flow cytometry. The present experiments prove that G1-cohorts grown 12 h under exclusion of oxygen accumulate in the late G1-compartment. The cytokinetic properties of these cells are not changed. In contrast the cytokinetic properties of anaerobically treated S-phase cells are changed; most of S-cells leave the cell cycle after they have attained the DNA content of G2-cells and continue to synthesize DNA without preceeding division. Cells with a DNA content up to the fourfold of normal values are found.

Growth characteristics of in vitro cultured Ehrlich ascites tumor cells under anaerobic conditions and after reaeration

The effects of deprivation of oxygen on proliferation kinetics of in vitro grown Ehrlich ascites tumor cells were studied by means of flow cytometry. The flow cytometric results obtained by applying the BUdR-H 33258 technique showed that 6--8 hours after establishment of anaerobiosis cells lose their capacity for proliferation and accumulate in the late G1-phase; during this time late S cells enter the G2 compartment but do not divide while cells, which are in G2+M at the beginning of anaerobiosis divide and enter G1. Cell cycle distribution remained constant up to about 20 hours, thereafter G1-cells enter the S-phase. Up to 24 hours of anaerobiosis cell number does not change and viability of the cells was not severely affected. Recultivation under aerobic conditions of 12 hours anaerobically treated cells revealed, that the cytokinetic properties of G1 cells were not impaired, while S-phase cells after reaeration did not enter G2 but began again to synthesize DNA forming cells with a DNA content greater than 4c. S-phase cells are most sensitive to deprivation of oxygen.

Endoscopic diagnosis of chemically induced autochthonous colonic tumors in rats

The suitability of using coloscopy as a diagnostic method is investigated with respect to colonic carcinomas induced locally by the administration of N-nitrosoacetoxymethyl-methylamine, N-methyl-N-nitrosourea, and methylnitro-nitrosoguanidine, or systemically by subcutaneous injection of 1,2-dimethylhydrazine in Sprague-Dawley rats. The endoscopic diagnostic examination proved to be clearly superior to methods of animal inspection, palpation, investigation for occult blood and exploratory laparotomy which have so far been employed in animal experiments with small rodents. The relevance of this method is discussed for the early detection of chemically induced colonic tumors, and the observation of tumor development under experimental cytostatic therapy.

Further investigations on the p-nitrophenylphosphatase activity of intact Ehrlich ascites tumor cells

The substrate specificity and the effects of nucleotides and SH-blocking agents on the p-nitrophenylphosphatase activity of intact Ehrlich ascites tumor cells (EAT) cells were studied. DL-beta-Glycerophosphate, o-phosphoethanolamine, cholinephosphate, glucose-6-phosphate, o-carboxyphenylphosphate,, phosphoenolpyruvate and AMP were not attacked by intact cells. ATP is greater than GTP is greater than UPT is greater than PPi is greater than pNPP were cleaved with decreasing velocity. A stimulation of the cleavage of p-NPP by the following nucleotides was observed with decreasing effectivity: ATP is greater than ADP is greater than GTP is greater than UTP; AMP was ineffective. The phosphatase activity was not affected by malate, tartrate and glutathion disulfide. The SH blocking agents diamide and thimerosal were more effective inhibitors of the pNPPase than of the ATPase activity, whereas the hydrolysis of ATP is more affected by the ATP analog adenylylimidodiphosphate. The present data are best compatible with a double headed enzyme: Both active sites interact with ATP, only one is active against p-NPP and sensitive against SH-blocking agents.