[Nocturnal changes in blood gases and pulmonary arterial pressure in chronic bronchitis patients with respiratory insufficiency (author's transl)]

Fourteen male patients with chronic bronchitis and respiratory insufficiency were monitored during nocturnal sleep by conventional polygraphy (EEG, EOG and EMG of the chin) associated with continuous recording of the mean pulmonary arterial pressure (PAP) and, in 50% of the cases, continuous measurement of O2 saturation. Six subjects were able to sleep long enough for oxygen saturation, blood gases and PAP values to be correlated with the various phases of sleep. Frequent, significant and sometimes abrupt peaks of hypoxaemia were observed; they usually, though not necessarily, occurred during paradoxical sleep. The most pronounced nocturnal changes in SaO2 were encountered in those patients who had the most severe hypoxaemia during daytime. Nocturnal fluctuations in PAP were also pronounced (with increases of more than 20 mmHg) and often paralleled changes in SaO2. Correlation between SaO2 and PAP was good in some patients ("responders") but poor or even lacking in others ("poor-or non-responders"). This preliminary study indicates that patients with chronic bronchitis may have severe exacerbations of pulmonary arterial hypertension during nocturnal sleep and warrant nocturnal oxygen therapy.

Immunofluorescent localization of type IV collagen and laminin in human skin and its application in junctional zone pathology

Purified antibodies against type IV collagen and laminin were used ot localize basement membranes by indirect immunofluorescence in various anatomical regions of normal and diseased human skin. The two proteins showed extensive codistribution. A continuous linear staining was found along the epidermal-dermal junction and around hair follicles, sebaceous gland acini and small capillaries. The same proteins also surrounded individual cells such as those found in vessels, hair erector muscles and subcutaneous tissue. Blister formation in bullous pemphigoi left type IV collagen and laminin on the floor of the blister, while the bullous pemphigoid antigen as detected by human autoantibodies was found on both sides of the blister. In solid basal cell carcinoma a strong staining was found around all tumour islands as well as focally within the cell clusters. This suggests that the tumour cells produce these basement membrane proteins but have lost, at least in part, control of polar deposition.

[Diagnostic accuracy of pulmonary vessel blood flow assessed by roentgenography--a comparison with haemodynamic data (author's transl)]

The article reports on an examination of the diagnostic accuracy in assessing the pulmonary vessel blood flow via x-ray films of the thorax in 323 children by means of a comparison with the haemodynamic data of four examiners, on the basis of a Yes/No (True/False) decision. Overall accuracy in the total group of examined children--depending on the experience of the examiners--was 60 to 66%; in children below 2 years of age, it was 63-69%, and in children over 2 years old it was 59-65%. In a Left-Right Shunt smaller than 35%, accuracy was between 33 and 63%; if the Left-Right Shunt was greater than 57%, it was 81-97%. Diagnosis of reduced pulmonary blood flow proved more difficult than of an enhanced flow. Sensitivity of the examination method was 53-71%, whereas its specificity was 57-70%.

[Right ventricular function in patients with transposition of the great arteries after atrial inversion (Mustard procedure) (author's transl)]

Twenty-nine patients with transposition of the great arteries (TGA) and intact ventricular septum underwent hemodynamic and angiocardiographic investigation 18,8 +/- 5,8 months after inflow correction (Mustard). The mean age at operation was 14,6 +/- 7,5 months and in all, a good anatomical result was achieved. The hemodynamic parameters such as cardiac index, pressures in all heart chambers as well as in the venous channels and arterial vessels were found within normal limits. The end-diastolic volume of the right ventricle (RVEDV) was closely correlated to body surface area (r = 0,697). It increased, however, more rapidly than in children with normal hearts. Mean RVEDV/m2 was 86 +/- 8 ml which is 123 +/- 10% of the normal values for children (70 +/- 13 ml) according to Graham et al. The mean ejection fraction (EF) of the right ventricle (58 +/- 7%) was only slightly below the normal range (65 +/- 7%). Thus, a good hemodynamic function of the RV can be assumed at least for the early postoperative years after a Mustard operation. It remains open, however, if the more rapid increase of RVEDV/m2 expresses the RV adjustment to the afterload of the systemic circulation or if this should be interpreted as an early sign of RV functional impairment.

Scleroderma fibroblasts: some aspects of in vitro assessment of collagen synthesis

Fibroblasts were cultured from skin biopsies of patients with systemic sclerosis in different stages of the disease. In vitro synthesis of collagen was checked after a pulse with tritiated proline. The ratio between type I and type III collagen was normal in all patients. Six of seven cultures derived from patients in the active state showed an increased synthesis of collagen relative to other proteins. Addition of serum (normal and diseased) to the culture medium did not stimulate synthesis of collagen in any culture with normal collagen synthesis.

Actin acetylation in Drosophila tissue culture cells

In a permanent cell line derived from Drosophila embryos, cytoplasmic actin is produced as an unstable precursor, which is subsequently converted to a stable form. This conversion results in a reduction in isoelectric point, with no apparent change in molecular weight. The conversion involves an enzymatic acetylation, and results in an insensitivity to aminopeptidase digestion, suggesting N-terminal blockage. Both the acetylated and unacetylated actins can participate in the assembly of F-actin, but with different efficiencies.

Sexual dimorphism of newborn mouse epithalamus after fractionated X-irradiation at late stage of organogenesis

Fractionated X-irradiation with 3 x 0.95, 3 x 1.05, 3 x 1.15, or 3 x 1.35 Gy on gestational days 11-13 in the mouse results in two discrete, clearly distinguishable forms of an epithalamic malformation observable on gestational day 18. Type A is characterized by a rhombic shape of the dorsal diencephalic sulcus which first narrows at the occipital edge. The habenular diameters in the plane of the habenular commissure are in the range between 81 and 88% of the control measurements. The anterior colliculi are quite well developed. The type B lesion is characterized by a rather narrow epithalamus with a sandglass-shaped dorsal diencephalic sulcus and habenular diameters that are only about 56 to 64% of the control values. With the exception of the group with the lowest radiation dose (3 x 0.95 Gy), the type B lesion predominates. The B:A ratios are 1.5 and 1.6 in the highest dosage groups, and show the most drastic increase to a ratio of 4.0 after application of 3 x 1.05 Gy. Type B lesions occur in female fetuses at a higher frequency than in males and thus shows a clear-cut correlation with the frequency and severity of neocortical lesions in the same individuals. This is again most marked in the 3 x 1.05 Gy dosage group, where the type B lesion occurs five times more frequently in females than in males. This sexual dimorphism in the reaction pattern of the epithalamus after X-irradiation in utero, can best be explained by postulating a causal link with the forebrain lesions which were recently shown to exhibit similar sexual dimorphism. We therefore postulate a retrograde transsynaptic degeneration of the thalamo-cortical fibres that develop pre-term, which is significantly expressed only after a low X-irradiation dose, but is partly abolished in the higher dosage groups. This leads to hypoplastic alterations of the epithalami, a secondary phenomenon to the neocortical lesions in the animals most affected. The resulting dysfunction of the epithalamus in the immediate neonatal period is then responsible for the preferential death of the animals with B-type lesions and also explains why female mortality is significantly higher than male mortality which occurs only in the 3 x 1.05 Gy dosage group.

Thrombosis of the inferior vena cava after closure of atrial septal defect

Although complications of atrial septal defect closure was rare, some sources of potential error should be kept in mind. In the case presented an enlarged Eustachian valve, mistaken as the lower rim of an atrial septal defect, was included in the direct repair and led to obstruction of the inferior vena cava. Caval thrombosis occurred subsequently. Early reoperation, resection of the Eustachian valve and removal of the thrombus were followed by an uneventful recovery.

Resistance of Species of the Drosophila Melanogaster Subgroup to Environmental Extremes

Resistance to the extreme stresses of high temperature-desiccation and low temperature were compared among six species of the melanogaster species subgroup of Drosophila. D. melanogaster was the most resistant to all stresses. The cosmopolitan species, D. melanogaster and D. simulans, were more resistant to cold stresses than the four endemic species, D. mauritiana, D. teissieri, D. yakuba and D. erecta. D. simulans, D. mauritiana and D. teissieri showed similar resistance to heat and desiccation, while D. yakuba and especially D. erecta were sensitive to these stresses. A prerequisite for the spread of the cosmopolitan species into temperate zones thus appears to have involved a level of resistance to cold stress exceeding that of the endemics. A greater resistance to heat and desiccation stresses, such as that found in D. melanogaster, may also be necessary for the invasion of more extreme environments. All species with the exception of D. erecta and to a lesser extent D. yakuba can survive 6 h at the extreme temperature of 34�C at 95% RH, and in addition most of those flies surviving stresses of this type are fertile. This suggests that these species can survive short stress periods in a humid microhabitat in the wild.

Sexual dimorphism of mouse fetal brain lesions after X-irradiation prior to gonadal differentiation

Fractionated X-irradiation of gestational days 11-13 in the mouse, with doses between 3 x 1.05 and 3 x 1.33 Gy resulted in rosette-like clusters of primitive ependym-resembling cells dispersed within the cortex walls. Quantification of these abnormalities showed a general prevalence in the female fetuses, especially due to the larger number of rosettes in the females than in the males. It was concluded that X-irradiation acts on sex-specific differentiation steps, which are fully developed at the beginning of the fetal period. As it was recently speculated that these are linked to an early divergence of gene expression between the sexes, we suggest that X-chromosome damage may be involved in the pathogenesis of the dimorphic lesion pattern. While, in principle, this will valid for any fetal tissue, it only becames evident in the forebrain because of the outstanding relationship between cell necrosis and rosette development in this specific organ.

Sex-dependent action of prenatal fractionated X-irradiation in the mouse. Biochemical findings

X-irradiation of pregnant NMRI-mice on gestational days 11-13 with 3 x 10.5 Gy increased postnatal mortality of the female offspring only. Weights, protein content and acetylcholinesterase, as well as Na,K-ATPase activities in the brains of all treated offspring, were changed. There were, however, no differences between females and males with respect to these parameters.

Nature of collagen in dermatofibrosarcoma protuberans

The nature of collagen from 2 cases of dermatofibrosarcoma protuberans was studied. For this purpose, the tumor tissue was carefully separated from adjacent normal dermis. The collagen types comprised in the tumor were identified by CM-cellulose chromatographic and SDS-gel electrophoretic analysis of the component alpha-chains. Semiquantitative evaluation of the relative type III content was established by separation of the cyanogen bromide peptides on gels of 12% polyacrylamide in SDS. These studies showed that dermatofibrosarcoma protuberans contains alpha 1(I)-, alpha 2-, and alpha 1(III)-chains as well, and corresponding type I- and type III-related CNBr peptides. Comparing the collagen from dermatofibrosarcoma protuberans to that of normal skin, the relatively increased type III content in the case of dermatofibrosarcoma protuberans becomes apparent.

X-irradiation of mice in early fetal period influences dose-dependently sex ratio of offspring until weaning

Fractionated X-irradiation of mouse fetuses on gestation days 11-13 resulted in a significantly increased postnatal mortality of female litters. This occurred only at 3 x 110 rad, which was the threshold for the formation of typical neuroepithelial, rosette-like malformations.

Collagen polymorphism in pathologic human scars

The collagen type composition of normal and pathologic scars was examined in comparison with normal skin from the same individual. Particular care was taken to separate scar tissue from adjacent normal dermis. After urea extraction, the tissue specimens were cleaved with cyanogen bromide. The presence of the dermal collagen types I and III was deduced from the electrophoretic distribution patterns of the CNBr peptides in 12% SDS-polyacrylamide gels. The intensity of the type III specific peptide bands correlates with the type III content of the samples. Using this method, the presence of both type I and III collagen can be proved in normal as well as pathologic scars. The type III content in older normal scars is slightly increased, whereas the type III content of pathologic scars is significantly increased in comparison with the type III content of normal skin. The electrophoretic CNBr peptide distribution pattern of pathologic scar tissue is almost the same as that of fetal skin. Both are clearly different from the peptide pattern of normal adult skin.

Dermal architecture and collagen type distribution

The human dermis consists of two morphologically different layers. A loose meshwork of thin collagenous fibres is characteristic for the adventitial dermis with includes the papillary and the periadnexal dermis. Thick, coarse collagen bundles are the main feature of the reticular dermis. Two different collagens, type I and type III occur in the dermis as shown previously by biochemical analyses. Antibodies specific for type I collagen or type III collagen and their corresponding precursors were used in indirect immunofluorescence tests to localize the various collagens in frozen sections of normal adult skin. Whereas type I collagen is found in all dermal layers, the main part of type III collagen can be found within the adventitial dermis. Antibodies against the precursor of type I collagen stain only a bandlike region immediately beneath the epidermis. Antibodies against the precursor of type III collagen stain the same regions as antibodies against the helical part of type III collagen.

SDS-polyacrylamide gel electrophoretic determination of type I and type III collagen in small skin samples

A sodium dodecylsulfate-polyacrylamide electrophoretic method, which in contrast to other biochemical procedures, e.g. differential salt precipitation or ion exchange chromatography and molecular sieve chromatography, is applicable to smallest amounts of protein, is shown to be suitable for the determination of the collagen types from small skin samples, such as routine skin biopsies. After urea extraction, the tissue samples are cleaved with cyanogen bromide. The resulting CNBr peptides derived from the different alpha-chains are resolved in 12% SDS-polyacrylamide gels. Densitometric profiles of the gel electrophoretic patterns correspond to the collagen type content of the tissue specimens. Comparing fetal to adult skin, the higher content of type III collagen in the case of fetal skin can be demonstrated.

Base sequence complexity of the stable RNA species of Drosophila melanogaster

The base sequence complexity of Drosophila transfer RNA (tRNA), 5S RNA, and 18S + 28S ribosomal RNA was determined by analyzing the kinetics of RNA-DNA hybridization on membrane filters. We find that Drosophila tRNA is made up from about 59 basic nucleotide sequences distinguishable by hybridization, suggesting that many of the 99 tRNA species resolved by reverse phase chromatography (RPC-5) are homogenic. In contrast 5S RNA was found to contain a single family of sequences. Either 18S ribosomal RNA (rRNA) alone, or 18S + 28S rRNA together, behaved kinetically as two sequence families, and the possible basis for this unexpected result is discussed.

The ribosomes of Drosophila. III. RNA and protein homology between D. melanogaster and D. virilis

The extent of interspecific homology between D. melanogaster and D. virilis for ribosomal RNA and ribosomal protein was examined using the techniques of two-dimensional gel electrophoresis, and RNA-DNA filter hybridization. Only 2 of the 71 ribosomal proteins resolved were found to be species specific, while comparisons of soluble larval hemolymph protein patterns showed little similarity. Depending on the technique employed, the sequence homology for 18S + 28S ribosomal RNA was found to be between 83-94%, and sequence homology for 5S rRNA was judged to be complete.

Macrophage inhibiting activity in serum and central lymph of Listeria-immune mice

Serum and central lymph from mice immunized with live Listeria monocytogenes six days previously and boostered four hours before collection exerted significant inhibition of macrophage migration in vitro. It is concluded that lymphokines or lymphokine-like products of the cellular immune reaction are released in vivo and are possibly instrumental in the generation of acquired cellular antibacterial immunity.

The ribosomes of Drosophila. II. Studies on intraspecific variation

Electrophoretic comparisons of 40S and 55S ribosomal subunit proteins from 18 strains of Drosophila melanogaster revealed the virtual absence of allelic variation. More detailed two-dimensional studies on the large subunit proteins in 6 of the strains demonstrated additional complexity but still no interstrain variation. The significance of these results is discussed with respect to present estimates of genic heterozygosity in natural populations.

Binding of a polycyclic hydrocarbon to mouse skin proteins

The tritium content of the L- and K-region of commercial available tritiated 1,2,5,6-Dibenzanthracene was measured and compared with the 3H-release after binding of the compound to mouse skin proteins. The results exclude an addition reaction to the K- and L-region and favour a substitution reaction at one C-atom.

Physical Upgrading of Heavy Crude Oils by the Application of Heat

Summary

Subjecting a heavy crude oil to mild thermal cracking conditions effects apermanent and significant reduction in its viscosity and specific gravity. Although all crudes are susceptible to cracking, the temperatures and timesrequired usually exceed those required to crack heavy crudes such as thosefound in the Athabasca tar sands. At temperatures below 1000°F, it has already been established that cracking of both pure hydrocarbons and petroleum can bedescribed by first-order kinetic equations. To use this fact, a reference mustbe established by which the amount of upgrading or conversion of crudeconstituents can be estimated. This was done by subjecting both the original crude and the ‘heat-treated’ oil to distillation under identical conditions.The residuum from the distillation of the treated oil was compared to that from the original crude to establish the ‘degree of upgrading.’

From such laboratory tests on a variety of crude oils, it has been possible to estimate the time-temperature history necessary to produce specific degrees of viscosity reduction for each. As a result, it is possible to estimate thefeasibility of utilizing heat in the reservoir to facilitate the production of heavy oil, or of using heat to facilitate the surface handling of oil alreadyproduced.

The permanent upgrading in physical properties occurs so slowly at 500°F that the use of temperatures below this level, as currently practiced with heated pipelines, will effect only a temporary improvement in oil fluidity. Attemperatures in excess of 700°F, coking may present serious operating problems unless residence times are kept very short.

Introduction

Crude oils of low API gravity and crude oils having a high pour point present production problems both in and out of the reservoir. To overcomesurface handling problems, the oil industry currently practices extensive and expensive blending of light oils and LPG with heavy crudes to make them easily handled in pipelines and storage facilities. An alternative remedial technique involves thermal cracking. Thermal cracking, with its attendant lowering ofpour point and viscosity, was used in Russia many years ago to facilitate the pumping of heavy crudes (1). Egloff and Morrell (2) proposed, in 1926, toseverely crack a high-pour-point oil at the wellhead to eliminate the need for pipeline heaters and diluents.