Three 4-coumarate:coenzyme A ligases in Arabidopsis thaliana represent two evolutionarily divergent classes in angiosperms

The enzyme 4-coumarate:CoA ligase (4CL) plays a key role in channelling carbon flow into diverse branch pathways of phenylpropanoid metabolism which serve important functions in plant growth and adaptation to environmental perturbations. Here we report on the cloning of the 4CL gene family from Arabidopsis thaliana and demonstrate that its three members, At4CL1, At4CL2 and At4CL3, encode isozymes with distinct substrate preference and specificities. Expression studies revealed a differential behaviour of the three genes in various plant organs and upon external stimuli such as wounding and UV irradiation or upon challenge with the fungus, Peronospora parasitica. Phylogenetic comparisons indicate that, in angiosperms, 4CL can be classified into two major clusters, class I and class II, with the At4CL1 and At4CL2 isoforms belonging to class I and At4CL3 to class II. Based on their enzymatic properties, expression characteristics and evolutionary relationships, At4CL3 is likely to participate in the biosynthetic pathway leading to flavonoids whereas At4CL1 and At4CL2 are probably involved in lignin formation and in the production of additional phenolic compounds other than flavonoids.

Stress response of rats to handling and experimental procedures

The effects were observed of moving male, adult Han:Sprague rats in their cages or of exposure to ether for 1 min on the plasma concentration profiles of 25 blood characteristics linked with stress and shock reactions. 5 min after the stress serum prolactin, corticosterone, thyroid-stimulating hormone, follicle-stimulating hormone, luteinizing hormone, triiodothyronine and thyroxin levels were elevated 150-500% compared with those in blood collected within 100 s of entering the animal room.

Heart rate (telemetrically recorded), packed cell volume,, haemoglobin and plasma protein content were 10-20% elevated 2-10 min after cage movement or 2-20 min after ether confrontation over those of controls sampled within 50 s, indicating circulatory and microcirculatory shock reactions.

Serum glucose, pyruvate and lactate concentrations rose by 20-100% 1-5 min after cage movement and 1-15 min after ether exposure. Phosphate, calcium, urea, apartate and alanine transferases, alkaline phosphalase and leucine arylamidase were not altered significantly by either stressor, while potassium and bound glycerol fell for 1 min and 5-20 min respectively.

The presence of a familiar animal attendant working in the room without touching the cages did not markedly affect the blood characteristics being studied.

Mutational analysis of 4-coumarate:CoA ligase identifies functionally important amino acids and verifies its close relationship to other adenylate-forming enzymes

4-Coumarate:coenzyme A ligase (4CL) is a key enzyme of general phenylpropanoid metabolism which provides the precursors for a large variety of important plant secondary products, such as lignin, flavonoids, or phytoalexins. To identify amino acids important for 4CL activity, eight mutations were introduced into Arabidopsis thaliana At4CL2. Determination of specific activities and K(m) values for ATP and caffeate of the heterologously expressed and purified proteins identified four distinct classes of mutants: enzymes with little or no catalytic activity; enzymes with greatly reduced activity but wild-type K(m) values; enzymes with drastically altered K(m) values; and enzymes with almost wild-type properties. The latter class includes replacement of a cysteine residue which is strictly conserved in 4CLs and had previously been assumed to be directly involved in catalysis. These results substantiate the close relationship between 4CL and other adenylate-forming enzymes such as luciferases, peptide synthetases, and fatty acyl-CoA synthetases.

Spontaneous short-term fluctuations in the daily pattern of heart rate, body temperature and locomotor activity in the laboratory rat

Heart rate (HR), body temperature (BT) and locomotor activity (LA) were measured continuously over 5 days in freely moving rats. In addition to the well-known circadian rhythms, all variables exhibited considerable fluctuations in amplitude mainly during the dark, but also in the light periods. The values of HR varied from 286 +/- 12 to 470 +/- 26 b.p.m. and BT from 36.15 +/- 0.15 degrees C to 38.45 +/- 0.25 degrees C. The large variability of HR, BT and LA within a single day was due more to large short-term fluctuations within periods of about 3-5 hours duration, than to differences between the light and the dark period. Good consistency of daily patterns and similarity of the 3 variables was found within the animals. Usually there were 3 or 4 regular peaks during the dark and often another peak 3-4 hours after the onset of light. Correlation coefficients, calculated on the basis of 5-min mean values, were highly significant (P less than 0.001) for LA vs HR (0.61-0.73), LA vs BT (0.40-0.53), and HR vs BT (0.61-0.68). Between-hour correlations were higher than these common correlations of 5-min values. HR vs BT (0.76-0.83) and LA vs BT (0.63-0.79) correlated as well as LA vs HR (0.72-0.83). The short-term fluctuations (within-hours) gave lower correlation coefficients for LA vs BT (0.23-0.32) and HR vs BT (0.29-0.41) than LA vs HR (0.40-0.70). This seems to result from a physiological delay of BT relative to HR and LA.

Sex differences in age development of a mouse inbred strain: body composition, adipocyte size and organ weights of liver, heart and muscles

The mouse inbred strain HLG has only recently been submitted for international registration. It has been widely used in radiological studies. Since these mice tend to become obese, they may be of interest for studies concerning fat metabolism. Therefore, the present ageing study examines the sex-specific development of body weight, body composition, adipocyte size as well as the organ weight of liver, heart and thigh muscles of the inbred strain HLG (54 males/53 virgin females) between day 40 and 360 of life. The body weight development showed a distinct sexual dimorphism, quickly increasing in the case of males but comparatively protracted in females until maturity. Significantly higher values for body and fat-free dry weight as well as body water were found in males of all ages. Body fat and adipocyte diameter were only higher in the 80 and 120 day-old males. Thus, the increase in female body weight resulted largely through a rise in body fat as additionally evidenced by the sex-specific correlation of characteristics. A 2-fold analysis of variance showed sex differences in the relative weights of liver and muscle, but not of the heart. A sex-specific close correlation was observed between body and liver weights in males until day 180. Correlations between body fat and other characteristics were only rarely found. Differences in coefficients of variation largely depended on the characteristics. A higher variability was also found for some characteristics in the youngest groups (40 days). A sex-specific difference was only seen in the case of body fat content for 60 day-old mice (female > male).

Influence of bleeding procedure and some environmental conditions on stress-dependent blood constituents of laboratory rats

The influence of experimental conditions on 10 haematological and blood chemical constituents were investigated in male Han:Wistar rats. Significant differences existed between values of haematological and chemical constituents of blood, sampled within 10 s, between 10 and 30, or between 30 and 60 s after decapitation respectively, The leucocyte count decreased quickly but the lactate concentration rose after decapitation. The interindividual coefficient of variance for the majority of the blood constituents was reduced markedly if blood was sampled within 10 s of decapitation. Significant differences in plasma protein and blood lactate concentrations existed between 2 rats kept in one cage, when the first rat was decapitated 20 s before the second one. Plasma protein concentrations differed significantly between rats bled at 9.00 am and 11.00 am. Significant differences in blood glucose and lactate concentrations existed between rats bled on 5 different days within a period of 10 days. Packed cell volume, eosinophilic granulocytes and plasma protein concentration differed significantly between rats kept in a room with a 12:12 light: darkness (LD) cycle and those living in a room with a 2.3:2.3 LD cycle.

Distribution of glomeruli in the renal cortex of Munich Wistar Frömter (MWF) rats

The glomerular distribution in the renal cortex of the Munich Wistar Frömter (MWF) rat, a substrain of the Munich Wistar rat selected for superficial glomeruli, was compared to that of a control strain (LEW/Ztm) between 10 and 150 days of age. While there were no significant differences in body growth, kidney weight, or growth of the renal cortex in these two strains, the average diameter of Bowman's capsule and of the glomerular tuft was significantly larger (about 12%) in rats of the MWF strain which were older than 60 days. In histological sections of kidneys of MWF rats in all age groups, many glomeruli in direct contact with the renal capsule were found; thus, this developmental step must have taken place before 10 days of age. The appearance of superficial glomeruli was due to a shift of glomeruli to a position just under the renal surface, the subcapsular zone or 'cortex corticis', which is normally free of glomeruli. For the rest of the renal cortex there were only slight differences in glomerular density and in total number of glomeruli per section between these two strains. These results lead us to suppose that superficial glomeruli belong to a special nephron type; thus, these glomeruli are not enveloped by parts of the proximal tubule.

Improved model for the induction of proestrus-like gonadotropin surges in long-term ovariectomized rats

In long-term (greater than 4 wk) ovariectomized rats the positive response of the gonadotropin release apparatus to a priming dose of estradiol is moderate as compared with that of proestrous rats exposed to endogenous estradiol. In the present study, high sensitivity to estrogen was restored in long-term ovariectomized rats by pretreatment with estradiol benzoate (EB, 20 micrograms, day 0) and progesterone (P, 2.5 mg, day 3). Estradiol benzoate (20 micrograms) given on day 5 induced proestrus-like surges of LH and FSH in the afternoon on day 6. Additional administration of P (2.5 mg at noon on day 6) had a facilitatory effect. Stimulation of LH release could be evoked in rats by the described regimen 1, 6 or 50 wk after ovariectomy. The long-term ovariectomized rat injected with EB and P as described might provide a useful model for neuroendocrinological investigations on the gonadotropin surge mechanism.

pH dependency in uptake of sulfonamides by bacteria

Sulfonamide-sensitive cells of Escherichia coli were incubated under standarized conditions with various sulfonamides and the quantity of sulfonamide uptake into the bacteria measured. The test substances reached a higher concentration inside the bacteria than in the incubation medium, the degree of accumulation varying for the individual substances despite uniformly applied incubation conditions. In all cases a pH dependency was detected which varied with the pKa values of the substances tested. On the basis of the pKa dependency of the pH effect, the sulfonamide uptake can be interpreted as being a passive diffusion process. Knowing the intracellular pH value, which was determined by the DMO method, it was then possible to calculate the theoretically expected value for the accumulation as a concentration coefficient. Since the calculated and experimentally determined values differ approximately by a factor of 2, an intracellular binding of the sulfonamides is assumed. The same results were obtained in cells of sulfonamide-resistant E. coli strains.

Intraspecies allometry: correlation between kidney weight and glomerular filtration rate vs. body weight

Allometric equations of the form of Y = a*BWb were calculated between body weight (BW) on the one hand and either kidney weight (KW) or glomerular filtration rate (GFR) on the other. By using strain and sex means obtained from 24 different inbred strains of adult mice or F1-hybrids environmental and genetical influences could be separated statistically. Thus, allometric equations reported in this study describe exclusively genetic influence. The parameters for intraspecies allometric equations obtained in these studies were compared to those in the literature presenting interspecies relationships. The double logarithmic regressions of KW vs. BW gave results different from the interspecies equation. The difference between intra- and interspecies results of allometric relationships may be due to the experimental exclusion of environmental influences. The regression parameters for GFR vs. BW obtained for the inbred strains, however, agreed very well with those of the empirical equation for interspecies relationship and also with the theoretically expected value. The dependence of GFR on BW was found to be GFR = 0.036*BW0.74 +/- 0.15, where GFR is measured in ml/min and BW in g. The exponent of 0.74 seems to be a valid biological constant that is genetically determined within and across species lines.

The ontogenesis of skin and organ characteristics in the Syrian golden hamster. II. Body and organ weights as well as blood glucose and plasma insulin levels

The ontogenesis of the organ weights of the liver, kidneys, adrenals, testes and ovaries as well as the blood glucose and plasma insulin levels were studied in a total of 464 golden hamsters of both sexes of the acromelanic white inbred strain Bio 1.5 and agouti coloured outbred strain Han:AURA. Familial and seasonal influences were excluded by means of randomisation (25 groups from 1-365 days of life). Body weight development was found to be sigmoid and showed significant differences in terms of age, sex, and strain. Liver and kidney weights developed in parallel. Here, too, strain differences (agoutis greater than acromelanics) were seen, and sex differences were observed in the case of the kidneys (females greater than males). The increased adrenal weight in male hamsters compared to females was in accordance with species- but not rodent-typical behaviour. Both the testes and ovarian weights varied considerably. Age as well as, in part, strain differences were seen in the case of the blood glucose and insulin levels. The continual development of body and organ weight could be explained in terms of physiological changes.

Glücklicher Ausgang einer intraoperativen Unterlassung

Four years after cholecystectomy and recurrent epigastric pain, a surgical sponge passed per anum in a 39-year-old man. Diagnostic procedures including clinical and laboratory examinations, ultrasound, coloscopy, and abdominal CT did not reveal any noteworthy residual changes by the foreign body. After 4 years in situ, the surgical sponge showed no alterations in structure. The representatives of the hospital concerned had to satisfy the patient's claims for damages. Pathology, technical diagnostic methods, and prognosis in cases of retained gauzes are presented. It is essential to count instruments and towels and advisable to use only single sponges in forceps in order to prevent intraoperative loss.

How the bacterial plant pathogen Xanthomonas campestris pv. vesicatoria conquers the host

Abstract Xanthomonas campestris pv. vesicatoria (Xcv) is the causal agent of bacterial spot disease on pepper and tomato. Pathogenicity on susceptible plants and the induction of the hypersensitive reaction (HR) on resistant plants requires a number of genes, designated hrp, most of which are clustered in a 23-kb chromosomal region. Nine hrp genes encode components of a type III protein secretion apparatus that is conserved in Gram-negative plant and animal pathogenic bacteria. We have recently demonstrated that Xcv secretes proteins into the culture medium in a hrp-dependent manner. Substrates of the Hrp secretion machinery are pathogenicity factors and avirulence proteins, e.g. AvrBs3. The AvrBs3 protein governs recognition, i.e. HR induction, when bacteria infect pepper plants carrying the corresponding resistance gene Bs3. Intriguingly, the AvrBs3 protein contains eukaryotic signatures such as nuclear localization signals (NLS), and has been shown to act inside the plant cell. We postulate that AvrBs3 is transferred into the plant cell via the Hrp type III pathway and that recognition of AvrBs3 takes place in the plant cell nucleus.

[Reoperation in recurrence of carcinoma of the esophagus, Cardia and stomach (author's transl)]

Reoperative surgery is performed with the object of restoring gastrointestinal passage or of pain relief and only rarely, for example in recurrence of an early carcinoma, with the object of curative resection. Out of 31 reoperations for such a purpose, a second resection (total or extended gastrectomy) was possible in 9 cases, gastric bypass or some other palliative operation in 12; in 10 cases, only a laparotomy was possible. The interval between the 1st and 2nd operations was 29 months in the resectable group and 17 months in the nonresectable group, the survival times 11 and 3.3 months respectively. Indications have to be considered separately for each patient.

Blood pressure in rats: a comparison of a multifactorial experimental design to measurements in an outbred stock

Systolic blood pressure was measured in males of 8 inbred strains and 1 outbred stock of rats 5 times over a period of 20 min on 5 consecutive days. The strain means ranged between 107.9 mmHg and 149.3 mmHg. The estimated variance between strains (V = 248.7 mmHg) was about 5 times higher than the variance within strains (V = 54.3 mmHg). The intraindividual variance within strains was relatively constant (V = 24.0-37.6 mmHg), while the interindividual variance varied to a great extent (V = 4.5-44.5 mmHg) from strain to strain. The outbred stock showed values of blood pressure and components of variance similar to those of a single inbred strain. Thus, by investigation of a battery of 8 inbred strains in a multifactorial experimental design a greater phenotypic variability due to genetic strain differences is achieved than by measurements in a single outbred stock.