Uptake and distribution of calcium, magnesium and potassium in cucumber of different age

Uptake and distribution of Ca⁺, Mg²⁺ and K²⁺ were investigated in plants of cucumber ( Cucumis sativus L. var. Cila) which had been cultivated for 12, 19, 32, or 53 days in complete nutrient solution with 1.0 m M Ca²⁺, 2.0 m M Mg²⁺ and 2.0 m M K⁺. The ⁺ concentration was about the same in roots and shoots, while the Ca²⁺ and Mg²⁺ concentrations were low in roots compared to shoots. The K⁺ concentration decreased with increasing leaf age, while the Ca²⁺ and Mg²⁺ concentrations increased, except in older plants with flowers and fruits, where an increased concentration was found in the youngest leaves. This is discussed in connection with increased indoleacetic acid (IAA) synthesis in the shoot. Excision of leaves at different levels from 21-day-old plants, followed by uptake for 24 h from the nutrient solution on days 22 and 23, resulted in no immediate reduction in Ca²⁺ (⁴⁵Ca) uptake. Transport of Ca²⁺ increased to leaves above and below the excision point and total Ca²⁺ uptake remained at the same level as for the intact plant. It is suggested that regulation of Ca²⁺ uptake is primarily achieved in the root while the distribution in the shoot is regulated by the accessability of negative binding sites.     

Low-Fat Diets May Prevent Weight Gain in Sedentary Women: Prospective Observations From the Population Study of Women in Gothenburg,Sweden

The Population Study of Women in Gothenburg, Sweden is an ongoing prospective study of female residents who were recruited from the local registry in 1968–1969 when they were 38–60 years old. The data presented here were collected from 361 healthy women who underwent a baseline physical examination including a supplementary dietary history interview and returned for a second general health examination 6 years later. This report identifies a subgroup of 57 women who were sedentary during their leisure time and appear to have been particularly susceptible to gaining weight as a function of the fat content of their diets. Specifically, longitudinal analysis of body weights in the whole sample revealed a statistical interaction between leisure-time physical activity and habitual dietary fat intake (energy-%), as reported at the baseline examination, in the prediction of subsequent weight change. Further stratified analysis suggested that weight changes were significantly dependent on dietary fat intake among the sedentary women only. High energy intake also predicted weight gain in the sedentary group, although the predictive value for a high-fat diet was of marginal significance after adjusting for total energy consumption. These results suggest that sedentary recreational activity plus a low-fat diet may have a combined contribution to weight change that is not equivalent to the sum of the separate effects. Such a synergy between two modifiable lifestyle factors seems highly relevant for prevention of obesity.     

Possible significance of changes in the energy metabolism for the release of liver lactate dehydrogenase and for the uptake and incorporation of [14C]-orotic acid into liver ribonucleic acid after partial hepatectomy

The mouse liver revealed no increased incorporation of [14C]-orotic acid into either the total acid-soluble fraction, the uridine triphosphate or the RNA at 6 and 24 h after partial hepatectomy. In regenerating mouse and rat liver, the concentration of adenosine triphosphate was decreased 15-20% at 6 h, but was in the same range as that of the controls at 24 h. The adenosine monophosphate concentration of mouse liver increased 4-fold and 2-fold at these times after partial hepatectomy, respectively. The results indicate no direct relationship between the energy metabolism and the uptake and incorporation of orotic acid into RNA of regenerating liver. The activity of mouse plasma lactate dehydrogenase 5 (LDH 5) was increased 12-fold at 6 h and 5-fold at 24 h after partial hepatectomy. In rat, the LDH 5 activity was increased 2-fold at 6 h but was not different from that of the controls at 24 h. An increased leakage of LDH 5, possibly related to the decreased energy content of the liver, was thus revealed by the partially hepatectomized mice.     

Riochemical and physiological effects in farmed Baltic salmon fed lipids containing xenobiotics extracted from Baltic herring

During a 2-year experimental period female baltic salmon (Salmo salar) were fed pellets impregnated with oil extracted from Baltic herring (Clupea harengus). This extract contained lipid-soluble xenobiotics present in Baltic herring, which constitute a major part of the natural diet of Baltic salmon. The fish were examined at the time of ovulation in November each year. After 2 years of feeding, the load of polychlorinated dibenzo-paradioxins and furans in the exposed group was about twice that in the control group, but still low compared with concentrations in feral Baltic salmon. In spite of the relatively low exposure level, several vital biochemical functions were disturbed in the treated fish. Organic skeletal variables were affected indicating that the bone metabolism had been altered. Furthermore, the activities of enzymes involved in steroid biosynthesis were affected, which could lead to disturbances in reproductive functions. Splenocytes from exposed fish sampled in November 1990 showed a reduced mitogenic response, indicating that their immune system was suppressed. Feeding the salmon with pollutant-impregnated pellets also resulted in an induction of the hepatic ethoxyresorufin-O-deethylase (EROD) activity after only 6 weeks of exposure. Likewise, morphological abnormalities, i.e. hypertrophic hepatocytes and various stages of hepatic degeneration, were already apparent after 6 weeks of exposure. However, no EROD induction or morphological responses were recorded at the second and third sampling event, i.e. after one and 2 years of exposure, respectively. this could indicate that some physiological functions may adapt to a restricted xenobiotic load.     

Early antibiotic treatment of reactive arthritis associated with enteric infections: clinical and serological study.

OBJECTIVE--To find out whether a 10-14 days'' course of antibiotics early in the course of reactive arthritis associated with enteric infections could reduce the severity and duration of the disease and whether the antibody response in patients with reactive arthritis associated with yersinia infection differed between those treated and those not treated with the antibiotics. DESIGN--Prospective multicentre trial in which patients were randomised to treatment or no treatment with antibiotics. Patients were seen at three and six weeks and three, six, nine, 12, and 18 months after their first visit. SETTING--Departments of infectious diseases in three hospitals in Linköping, Malmö, and Stockholm, Sweden. PATIENTS--40 Consecutive patients who had had symptoms of reactive arthritis associated with enteric infection for less than four weeks. INTERVENTIONS--20 Patients were allocated to treatment with antibiotics and 20 patients did not receive antibiotics. All patients received non-steroidal anti-inflammatory drugs, and four also received intra-articular steroid injections after at least six weeks'' observation. MAIN OUTCOME MEASURES--Arthritic symptoms assessed clinically and by using Ritchies'' index; blood measurements reflecting inflammatory activity; serum IgG, IgM, and IgA antibody titres; HLA tissue type. RESULTS--No difference was observed concerning duration of arthritis, grade of inflammation, and number of joints affected between patients treated and those not treated with antibiotics. Furthermore, there was no significant difference between the two groups in erythrocyte sedimentation rate and haptoglobin, IgG, and IgA concentrations. All values had returned to normal within three months. No patient developed chronic arthritis, but sustained slight arthralgia occurred in three patients. The HLA-B27 antigen was found in 23 (58%) of the patients, and its presence did not affect clinical outcome. The IgG, IgM, and IgA antibody responses were similar in patients treated with antibiotics and those not treated. CONCLUSION--Short term antibiotic treatment has no beneficial effect on the clinical outcome of reactive arthritis associated with enteric infection.     

木焦油污染土壤中微生物特性的空间变异性研究

运用地统计学方法研究了木焦油污染土壤中微生物量、微生物群落结构、微生物活性等的空间变异特征.分别采用26种主要磷脂类脂肪酸(PLFA)的总含量(totPLFA)、PLFA的第一主成分和第二主成分(PLFA PC1和PC2)以及土壤培养过程中CO₂-C的累积释放量(Cre)来表征土壤中的微生物量、微生物群落结构以及微生物活性.结果表明,多数微生物特性指标均存在不同程度的空间自相关性,其半变异函数曲线可用带块金效应的球状模型进行拟合.变量的空间相关距离在2.50～16.60 m之间.PLFA PC1、totPLFA和Cre均具有较强的空间依赖性,其相对结构变差（由结构性因素引起的空间变异）分别为82.3%、79.6%和64.7%,而PLFA PC2 不存在明显的空间依赖性.克立格空间插值图表明,样地中存在几处微生物相对密集分布且代谢活性较高的区域,其中优势微生物菌群是由PLFAs 16:1ω7t,cy17:0,18:1ω7 和cy19:0所表征的革兰氏阴性细菌.土壤中主要污染物多环芳烃含量和空间分布是影响微生物特性空间分布格局的重要因素之一.