Genetic variation in erythrocyte NAD levels in the mouse and its effect on glyceraldehyde phosphate dehydrogenase activity and stability

During a screening of inbred strains for enzyme variation in glycolysis, differences were found in glyceraldehyde phosphate dehydrogenase (GAPDH) activity between C57BL/6J and SM/J mice. Segregation analysis did not reveal unequivocal monogenic inheritance. Dialysis of hemolysates caused decay of enzyme activity, especially in C57BL animals, which could be prevented by the presence of NAD. This led to the finding that erythrocyte NAD levels were threefold higher in SM than C57BL animals and, although additively inherited, did not appear to be monogenic. This is comparable with but independent of the differences and effect of erythrocyte NADP levels on glucose-6-phosphate dehydrogenase activity reported by R. P. Erickson [(1974) Biochem. Genet. 11:33] and emphasizes the range of mechanisms that can be involved in the genetic control of enzyme activity in mammalian systems.We thank the MRC for financial support.     

Determination of GAB A Levels by a [3H]Muscimol Radioreceptor Assay

Abstract: A [³H]muscimol radioreceptor assay was used to measure the levels of GAB A in mouse brain. The method is based on the competitive inhibition of [³H]muscimol binding to the GABA receptor by GABA extracted from tissue. The specificity and accuracy of the method was established by comparative measurements of GABA levels by gas chromatography. GABA levels obtained by radioreceptor assay (R) and gas chromatography (GC) in different areas of mouse brain were (in μmol/g tissue ± S.E.M.): cerebral cortex 1.41 ± 0.06 (R), 1.50 ± 0.03 (GC); corpus striatum 1.70 ± 0.05 (R), 1.66 ± 0.01 (GC); cerebellum 1.15 ± 0.04 (R), 1.11 ± 0.07 (GC); hippocampus 1.35 ± 0.04 (R), 1.43 ± 0.04 (GC). The sensitivity of the assay was 5 pmol of GABA, which is sufficient to measure GABA levels in brain. The technique described is simple and rapid and it can be used for unpurified tissue extracts.     

Neopterin and Biopterin Levels in Patients with Atypical Forms of Phenylketonuria

The pattern of unconjugated pterins in liver tissue and in urine from patients with atypical forms of phenylketonuria with hyperphenylalaninemia (HPA) has been investigated with a high performance liquid chromatographic technique. Two patients with defects in the biosynthesis of biopterin have been shown to have higher than normal levels of neopterin and lower than normal levels of biopterin. In contrast, a patient with HPA due to a deficiency of dihydropteridine reductase has the reverse urinary pattern, i.e., high biopterin, low neopterin. These results indicate that the ratio of neopterin to biopterin in urine can be of value in discriminating between HPA due to a deficiency of phenylalanine hydroxylase (classic PKU), HPA due to dihydropteridine reductase deficiency, and HPA due to a block in the biosynthesis of biopterin.     

Quantitation of serum immunoglobulins G, M, and A in the rhesus monkey (M. mulatta) using human monospecific antisera in the enzyme-linked immunosorbent assay: developmental aspects

Using human monospecific antisera, several parameters have been optimized for the micro-ELISA "sandwich" technique used in the quantitative measurement of total serum IgG, IgM and IgA levels in rhesus monkeys. Representation of the optical density as a four-parameter logistic function provided excellent fits of the data over a wide choice of dilutions of human antisera used for coating the ELISA plates and for the peroxidase-conjugated antisera used in the system. The micro-ELISA "sandwich" technique was shown to be specific, reliable, sensitive, and economical for use in the routine measurement of total serum IgG, IgM and IgA levels in the rhesus monkey.     

Protein synthesis during outgrowth of Bacillus subtilis spores. A two-dimensional gel electrophoresis study

Abstract To know if significant disulfide reduction was an important event during Streptomyces spore germination, the thiol-disulfide ratio was studied. Sulfhydryl and disulfide levels were determined by the quenching reactionof the fluorescence of fluorescein mercuric acetate. In the first 2 h of germination (darkening of spores), no significant changes in both levels were found. During spore swelling, the sulfhydryl content increased, whereas the disulfide content decreased. This increase in sulfhydryl groups was mainly occurring (93%) in the spore soluble fraction. Our data allowed us to discard the possibility of a major change in the thiol-disulfide ratio during initiation of Streptomyces spore germination.     

Using functional groups to investigate community response to environmental changes: two grassland case studies

Functional groups (FG) are an useful generalization to investigate environmental change effects on biotic communities. Assigning species to FGs is a contextual task and carries an arbitrary element, regardless of whether the grouping is obtained a priori or by sophisticated numerical methods. Using two grassland community case studies, we show that even simple FG allocation based on growth form, architecture and longevity (plants and mosses), or foraging characteristics (above-ground invertebrates) can be useful to increase our understanding of community processes. For example, the sensitivity of organisms to climate change increases with trophic rank and is higher in disturbed than in undisturbed communities. Complexity of interaction webs (in terms of web connectance), however, is larger in undisturbed than in disturbed communities. A significant and important relationship is likely to exist between anthropogenic disturbances, community complexity and the ecosystem effects of climate change. Trophic interactions may be disrupted much easier by climate changes in disturbed than in undisturbed communities where complexity may be buffering these effects.     

Changes in plasma levels of testosterone during male-male interactions in the song sparrow,Melospiza melodia: time course and specificity of response

Summary Previous investigations have shown that malemale interactions over territory boundaries result in an increase in plasma levels of testosterone (T). In order to determine the time course of this increase following an agonistic challenge, male song sparrows, Zonotrichia (= Melospiza) melodia, were exposed to simulated territorial intrusions. Responding males were captured at intervals after onset of the intrusion for up to 60 min. Plasma levels of T were elevated by 10 min after onset of the challenge, and remained high in birds sampled 10–60 min after onset of the intrusion. In addition, plasma levels of luteinizing hormone (LH) increased and were significantly elevated after 10 min of stimulation. The results suggest that at least the prolonged elevation of T secretion precipitated by a male-male interaction was mediated via an increase in LH release. However, the initial surge of T levels in plasma may be LH independent. p Investigations of captive birds confirmed that circulating LH and T levels increased when male song sparrows were challenged by a conspecific male. Challenges involving a male house sparrow, Passer domesticus, had no effect suggesting that responses to male intrusions were species characteristic and not a result of general arousal. Further, auditory stimuli (vocalizations) alone, and visual stimuli (a devocalized male) alone were less effective in stimulating an increase in secretion of T than a combination of auditory and visual stimuli.Abbreviations DHT dihydrotestosterone - LH luteinizing hormon; - T testosterone     

Response of tomato (Lycopersicon esculentum Mill.) growth to different phosphorous levels and sowing dates

A field trail was carried out at the University of Agriculture Peshawar during spring, 2013 in order to evaluate the effect of different levels of phosphorus fertilizer and various planting times on the growth and development of tomato. The main objective of the research work was to investigate the best sowing time for tomato in combination with suitable dose of P fertilizer in order to get maximum yield of tomato in the climatic conditions of Peshawar. RCB Design with split plot arrangements was used in the trail. The main factor (phosphorous levels of 0, 90, 110, 130) was allotted to main plots while sowing dates in sub plots. A total twelve treatment were replicated thrice. Maximum days to flowering (39.583?days) and fruiting (46.167?days) obtained in the late sowing. Minimum days to flowering (39), minimum days to fruiting (38.778?days) were taken by the early sowing. Maximum number of branches (27.778), maximum fruit length (6.0222), maximum fruit with (6.1667), maximum fruit yield (24.653?tons?ha^?1) was produced when the plot fertilize with 130?kg?P?ha^?1. Maximum number of fruit?plant^?1 (29.778) were produced with application of 130?kg?P?ha^?1, minimum number of fruits (23.667?cm), fruit width (3.778?cm), fruit length (4.3667?cm), plant height (56.300?cm) were obtained from the controlled treatment. Among the various treatment studied in experiment, it is concluded that early planting of the tomato in the summer season i.e. in the start of March and the use of higher dose of P (130?kg?P?ha^?1) is very beneficial for the excellent growth, development and yield of tomato crop.     

Circulating visfatin levels and cancers risk: A systematic review and meta-analysis

Visfatin levels have been reported to be abnormal in many types of cancers. However, epidemiological studies yielded inconsistent results. Therefore, a meta-analysis was performed to assess the association between circulating visfatin levels and cancer risk. A systematic search was conducted for relevant studies in health-related electronic databases up to March 2018. Data related to standard mean difference (SMD) and overall odds ratio (ORS) were collected and analyzed. Summary SMD and pooled OR with 95% CIs were calculated using a random-effect model. Funnel plot and Egger's linear regression test were conducted to examine the risk of publication bias. A total of 27 studies with 2,693 cases and 3,040 healthy controls were included in meta-analysis for pooling SMD analysis. The results of the meta-analysis showed a significant higher visfatin levels in patients with various cancers than in controls, with a pooled SMD of 0.88, 95% CI = 0.56–1.20, p = 0.000. In subgroup, metaregression, Galbraith plot, and sensitivity analysis showed no substantial difference among all the analyzed factors. Data from 14 studies were also used for pooling ORs analysis. Metaresults revealed that high visfatin levels were associated with cancer risk (OR = 1.24, 95% CI: 1.14–1.34, p = 0.000). No evidence of publication bias was observed for pooling ORs and SMD analysis. This meta-analysis indicated a significant association between high circulating visfatin levels and increased risk of various cancers. Visfatin may represent a potential biomarker for early detection of cancers who may benefit from preventive treatment.Note.     

Relationships among climate,latitude and migration: Australian butterflies are not temperate-zone birds

We examined the distribution of butterflies over the mostly arid and semi-arid continent of Australia and analyzed the proportion of migrant species and species diversity with respect to an array of climatic and geographic variables. On a continent-wide scale, latitude explained virtually no variance in either proportion of migrants (r ²=0.01) or species diversity (r ²=0.03) in Australian butterflies. These results are in marked contrast to those for temperate-zone birds from three continents where latitude explained between 82 and 98% of the variance in frequency of migrants and also accounted for much of the variance in bird species diversity. In eastern Australia where rainfall regimes are similar to those in temperate Europe and North and South America, latitude explains 78% of the variance in frequency of butterfly migrants. In both eastern and central Australia, latitude also accounts for relatively high proportions of the variance in species diversity. Rainfall patterns and especially soil moisture are negatively associated with migration frequency in Australian butterfly faunas, both alone and in combination with other climate variables. Where moisture levels are relatively high, as in eastern Australia, measures of temperature are associated with migration frequency, a result consistent with findings for temperate-zone birds, suggesting latitude is a surrogate for temperature. The ultimate causes of migration in temperate-zone birds and Australian butterflies are the uneven temporal, and in Australia also spatial, distribution of resources. Uneven distribution is brought about primarily by temperature in temperate regions and by erratic rainfall over much of arid Australia. As a key determinant of productivity, especially in the tropics and subtropics, aridity is likely to be an important determinant of the global distributions of migrants. Received: 14 July 1999 / Accepted: 12 January 2000