bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nodulins in root nodule development: function and gene regulation
Authors: Govers Francine , Bisseling* Ton 
Published: November 2023

Abstract
The symbiotic interaction between bacteria of the genus Rhizobium and leguminous plants leads to the establishment of nodules, specialized organs on the roots of the host plant in which the Rhizobium bacteria fix atmospheric nitrogen. The formation of root nodules is known to proceed through a series of characteristic stages (Vincent 1980). Prior to the actual infection, the symbiotic partners recognize each other and the bacteria become attached to the root hairs which then start to curl. The bacteria are entrapped in the curls and they induce the plant cells to deposit cell wall-like material from which a tubular structure is formed, the infection thread. Within the growing infection thread the bacteria multiply, but in front of the growing infection thread tip, in the cortex, mitosis is induced and a nodule primordium is formed. Once the infection thread tip has reached the primordium the bacteria are released in the plant cells and they are enclosed by a membrane. In plants which have indeterminate nodules, for example pea and alfalfa, a meristem is formed at the apical site of the nodule primordium. Continuous cell division, cell differentiation and cell enlargement finally result in a specialized plant organ.
Interactions between macrofaunal epiphytes and their host algae
Authors: Williams* Gray A , Seed† R 
Published: November 2023

Abstract
Marine algae provide a suitable habitat for a wide range of mobile and sessile macrofauna. Many of these organisms are permanent members of the epiphyton, whereas others utilize the host in a more transient fashion. Different types of algae support different suites of epiphytes according to the resources which the former provide. These include food and shelter as well as surfaces for attachment. Although some epiphytes are beneficial, others may impose a high selective cost on their host algae. Consequently the dynamic interactions between algae and their epiphytes are often extremely complex and not easy to categorize. In general, algae attempt to maximize associations with beneficial epiphytes and minimize encounters with those which impose excessive cost. Such complex interactions and the often close interdependence of epiphytes and host suggest a considerable degree of coevolution, though at present there is little conclusive evidence for this. This intriguing yet surprisingly neglected field of coastal ecology is clearly one which merits further detailed study.
Herbivorous fishes: feeding and digestive mechanisms
Authors: Horn Michael H 
Published: November 2023

Abstract
Feeding and digestion are sequential processes that seem to be especially tightly linked in herbivores, which are faced with a food resource not only low in protein and locked inside indigestible cell walls but also often chemically or morphologically defended. Herbivorous fishes browse or graze (if sediment is ingested) on their algal or seagrass foods with varying degrees of selectivity using a closely-spaced set of cropping or scraping teeth. These teeth may be conical or spatulate, smooth-edged, or cuspidate, flexible or rigidly attached, hinged or entire, separate and chisel-like or fused to form a beak-like structure.
Introduction
Authors: Dockray G J 
Published: November 2023

Abstract
Studies of the function and dysfunction of CNS systems that use CCK as a transmitter have now entered an especially exciting phase. In particular, the development in recent years of orally active antagonists for CCK receptors has opened the way for experimental studies that were hitherto impossible. The idea that CCK has a transmitter function in the CNS has developed over the last 15 years on the basis of evidence from many different disciplines. Even so, the availability of antagonists has been of crucial importance because for the first time it has become possible to formulate and test specific hypotheses of the functions of CCK in the intact nervous system.
Studies of gastrin/CCK receptors using functional isolated preparations
Authors: Patel Mina , Spraggs Colin F 
Published: November 2023

Abstract
CCK is widely distributed in the CNS, and attention at this symposium has focused on the potential central activities of this family of peptides. In addition, gastrin (G-17) and CCK are important physiological mediators of digestive function (Walsh 1987; Dockray and Gregory 1990). These observations have suggested the possibility of a number of therapeutic indications for selective agonists and antagonists at CCK receptors for use in the treatment of both CNS diseases (anxiety and schizophrenia) and gastrointestinal diseases (peptic ulceration, mucosal hyperplasia and tumour growth, motility, and digestive disorders).
Gastric mechanisms in CCK satiety
Authors: Moran Timothy H , McHugh Paul R 
Published: November 2023

Abstract
A role for the brain-gut peptide CCK in the control of food intake was originally proposed in 1973 by Gibbs et al. (1973a). Since that time, a range of experiments has been carried out detailing the actions of CCK on food intake, examining the mechanisms by which it may exert these effects, and addressing the potential relationship of the actions of exogenously administered CCK to a physiological role for the endogenously released peptide. In this chapter, we shall attempt to place CCK into an integrative chain of physiological events produced by the entrance of ingested food into the gastrointestinal tract and resulting in the termination of food intake. We shall review our own experimental results and those from other laboratories and evaluate the hypothesis that at least part of the inhibition of food intake produced by exogenous CCK results from mimicking the actions of the endogenous peptide in the inhibition of gastric emptying.
Selective CCK receptor antagonists and macronutrient consumption in the rat
Authors: Francis John , Cooper Steven J 
Published: November 2023

Abstract
It has been shown that the selective CCKA receptor antagonist devazepide reliably blocked the reduction in food intake produced by exogenously administered CCK-8 (Dourish et al. 1989a). Reidleberger and O’Rourke (1989) demonstrated that devazepide administered alone increased food intake in rats deprived of food for 1 h. Dourish et al. (1989b) have shown that not only devazepide but also the selective CCKB receptor antagonist L-365,260 increased food intake in satiated rats. The increases in food intake in these experiments were modest, and rats had to be deprived of food for only a short period of time or presatiated before the effects of the antagonists could be observed.Liddle et al. (1986) showed that neither carbohydrates nor fats, high percentage components of test meals, caused significant CCK release in rats. Only ingestion of a protein meal (casein) caused significant increases in plasma CCK concentration. Therefore it would seem that ingestion of a protein-rich diet would cause optimum CCK release during feeding. If CCK release is dependent on macronutrients (protein in the rat), then it follows that the effects of selective CCK antagonists on food intake may in turn be dependent on the nutrient composition of the diet. In general it would be expected, on this argument, that increases in intake produced by antagonists should be more closely related to protein ingestion than to either fat or carbohydrate ingestion (but see also Chapter 18 of this volume).
A study of the ‘coexpression’ of CCK and tyrosine hydroxylase messenger RNAs in the rat substantia nigra
Authors: Kiyama H , McGowan E , Emson P C 
Published: November 2023

Abstract
Developments in the technique of in situ hybridization using enzyme-labelled or biotin-labelled DNA probes have enabled us to utilize a combination of isotopic and non-isotopic in situ procedures to demonstrate the presence of two messenger RNAs (mRNAs) in one cell, i.e. ‘coexpression’ studies (Kiyama and Emson 1990). The study of ‘coexpression’ is a logical development of many of the earlier studies of coexistence, where double-labelling techniques using antibodies visualized two or more immunoreactivities in a single cell (H6kfelt et al. 1980a). The problem with methods used to demonstrate coexistence was that they depended on the use of antibodies which recognized, to variable extents, epitopes related to the desired antigen. Thus in studies of coexistence possible cross-reactivity of the antibodies used may confound the study and the application of drugs such as colchicine is often required to increase the neuronal content of the antigen. As colchicine itself can induce changes in neuropeptide gene expression, the use of this drug in neuroanatomical studies needs to be carefully controlled (Kiyama and Emson 1991) as it may result in false positives in coexpression studies.It was because of these potential problems with present coexistence studies that we developed a technique that enabled us to use two oligonucleotide probes (one radio-labelled and the other non-isotopically labelled) to visualize two mRNAs in a single neuron.
CCK and movement disorders
Authors: Boyce Susan , Rupniak Nadia M j. 
Published: November 2023

Abstract
Basal ganglia diseases seriously compromise an individual’s ability to perform activities of daily living, and many limitations are associated with current treatments. Movement disorders range from akinetic/hypokinetic syndromes such as Parkinson’s disease, where movement is extremely impoverished, to hyperkinetic conditions involving excessive and uncontrollable movements as in Huntington’s chorea and drug-induced dyskinesias. The profound effect of dopamine receptor agonists and antagonists on movement clearly implicate abnormalities of dopamine function in aberrant motor control. The clinical similarity between drug-induced and spontaneous movement disorders further suggests a common pathophysiology. The close association of CCK with dopamine in the mesolimbic and basal ganglia structures suggests that it may also be involved in the regulation of motor activity. In this chapter we shall discuss the functional interactions of CCK and dopamine, the potential use of CCK agonists and antagonists in the treatment of movement disorders, and the possible problems associated with such therapies.
CCK and opioid interactions in the spinal cord
Authors: Dickenson Anthony H , ullivan Ann F , Magnuson David S 
Published: November 2023

Abstract
CCK is present in widespread areas of the CNS including the spinal cord, where it is found in high levels, and released from those areas of the dorsal horn involved in the transmission and modulation of sensory messages. (Yaksh et al. 1982; Yaksh and Noueihed 1985; Williams et al. 1987). There is evidence that CCK not only produces neuronal excitation in the dorsal born (Jeftinija et al. 1981; Dickenson and Magnuson 1989) but can also act to reduce the antinociception produced by morphine and yet produce analgesia in other circumstances (Baber et al. 1989). The ability of CCK to interfere with morphine analgesia may be relevant to the clinical states where morphine responsiveness is reduced (Arner and Meyerson 1988). We have used recordings of nociceptive neurons in the rat spinal cord to gauge the effects of a variety of opioid receptor agonists on the transmission of peripheral sensory responses in the anaesthetized animal (Dickenson et al. 1987). Clear but independent inhibitions of the noxious evoked activities of these cells follows the activation of µ and o opioid receptors (Dickenson et al. 1987; Sullivan et al. 1989). Here we have studied the ability of CCK to interfere with µ and o opioid actions in the spinal cord and by the use of antagonists attempted to identify the CCK receptor subtypes involved. The recording of sensory neurons allows the actions of these agents to be studied without the complication of sedative, motor, or motivational effects influencing the findings.
Overview of epidemiological findings, physiological effects, and proposed mechanisms of biological interaction with low-level electric and magnetic fields
Authors: Hamnerius Yngve 
Published: November 2023

Abstract
Intense electric and magnetic fields have long been known to cause biological effects. The mechanisms are well known, e.g. heat production or triggering of nerve cells. However, research results from the past decade give evidence in numerous experiments that there are also biological effects of low-level electric and magnetic fields. The evidence for effects comes from both epidemiological and experimental studies.
Resonant ion-transport phenomena: possible mechanisms
Authors: Durney Carl H 
Published: November 2023

Abstract
Recent reports in the literature suggest that biological responses to combined d.c. and a.c. magnetic fields occur within narrow ranges of both frequency and a.c. magnetic field strengths, i.e. within frequency and amplitude ‘windows’. Furthermore, this resonance response seems to be related to the cyclotron ·frequency of the bare (unsolvated) ion. Since most familiar mechanisms would show an increased response with increased field strength, the observation of an amplitude window suggests a possible unfamiliar mechanism related to the presence of combined d.c. and a.c. magnetic fields. Blackman et al. (1985) found that certain combinations of a.c. magnetic field strength, d.c. magnetic field strength, and frequency changed calcium efflux in chick-brain preparations. Thomas et al. (1986) found that combined d.c.-a.c. magnetic fields strongly affected rats’ abilities to press levers within a narrow time window after receiving a stimulus. Smith et al. (1987) showed that combined d.c. and a.c. magnetic fields caused a strong resonance response with frequency in the motility of diatoms placed on the surface of an agar substrate impregnated with calcium. The prominent characteristics of these observations seem to be:
Electromagnetic field-induced permeability of the blood-brain barrier shown by immunohistochemical methods
Authors: Salford Leif G , Brun Arne , Eberhardt Jacob , Malmgren, Lars , Persson Bertil R R 
Published: November 2023

Abstract
The mammal brain is protected from potentially harmful compounds in the blood by the so-called blood-brain barrier (BBB)- a selectively permeable, hydrophobic barrier which is readily crossed by small, lipid-soluble molecules, (Rapoport 1976; Oldendorf 1977). Certain lipid-insoluble molecules such as glucose also readily cross the cell layers constituting the barrier via carrier proteins that have a high affinity to specific molecules.
European Exobasidiales and their galls
Authors: Ing Bruce 
Published: November 2023

Abstract
Exobasidiales are obligate parasites on leaves and shoots of Ericaceae, Lauraceae, Saxifragaceae, and Theaceae. They are heterobasidiomycetous fungi with no vegetative structures of their own, utilizing the somatic tissues of their hosts to support either systemic or annual mycelia and spore producing organs. The European genera are reviewed including observations on morphology, host species, and distribution. The extent of gall formation varies, from thickened, discoloured leaf spots in Arcticomyces and some Exobasidium species, through well-developed leaf pouch galls caused by Exobasidium to the clavarioid stem galls of Laurobasidium. A key to European species, based on host damage, is provided.
The communities associated with the galls of Andricus quercuscalicis (Hymenoptera: Cynipidae) an invading species in Britain: a geographical view
Authors: Schonrogge K , Stone G N , Cockrellt B , Crawley M j. 
Published: November 2023

Abstract
The agamic knopper gall of Andricus quercuscalicis in Britain provides an opportunity to investigate the guild associated with a cynipid gall in the process of its development. Species reared in association with the knopper gall include inquilines, which develop in the gall without having direct contact to the gall-causing lava, and parasitoids, both of the gall wasp and of the inquilines. Most of the members of the guild associated with A. quercuscalicis are polyphagous and bi- or multivoltine (that is, they attack more than one gall and have two or more generations per year) and, therefore, need alternative hosts, constituting ecological links between A. quercuscalicis and the local cynipid community in general. An extensive rearing programme of galls collected in Britain and on the European continent was carried out to examine qualitative and quantitative variations on different spatial scales.
Structure-activity studies of natural products with anti-inflammatory/ immunomodulatory effects
Authors: Borlin L 
Published: November 2023

Abstract
Pharmacognosy, in contrast to medicinal chemistry, can start from an observed activity of a drug used in man or animals. Subsequent bioassay-directed fractionation can then lead to the discovery of previously unknown chemical structures for further structure-activity studies. In the search for ‘new’ substances which influence the immune system, many possible biological targets are available.
Search for noncariogenic sweeteners from medicinal plants
Authors: Kinghorn A D , Suttisri R , Lee I S 
Published: November 2023

Abstract
Naturally occurring carbohydrate or caloric sweeteners such as sucrose are still the most widely used sweetening agents. Sucrose is paramount among sweet compounds in that it produces sweetness that is unmasked by any other taste sensation. However, quite large quantities of sucrose are necessary to sweeten foods, beverages, and medicines, and it is now accepted that sucrose is the main dietary source of dental caries in developed and developing countries alike. In addition, the abundant usage of carbohydrate sweeteners can result in other deleterious consequences such as high caloric intake and nutritional imbalance. Therefore, much effort has been expended towards the discovery of additional examples of highly sweet, non-nutritive, organic molecules that do not promote dental caries, especially for use in diabetic and dietetic products.
The chemistry and bioactivities of some natural products from Chinese herbs
Authors: Zhou B N 
Published: November 2023

Abstract
The abundant resources of medicinal plants in China and the rich empirical knowledge of Chinese folk medicine, which has accumulated over several millenia, encouraged us to embark on chemical and pharmacological studies of Chinese traditional medicine. The aim of our laboratory is the investigation of herbs with proven clinical efficacy. Over recent years, we have successfully isolated several lead compounds and some new natural products from Chinese traditional medicines. In this chapter, the chemistry of pseudolaric acid (an antifungal agent), yuanhuacin (a specific protein kinase C phorbol ester receptor antagonist), huperzine A (a compound used for treatment of senile dementia), and sarmentosin (a serum glutamate pyruvate transaminase (SGPT) lowering agent for hepatitis patients) is reviewed. Chemical and pharmacological studies were completed in our institute, and the compounds mentioned have been recommended in China for clinical trials.
The role of PEPC phosphorylation in theregulation of C4 photosynthesis
Authors: Gadal P , Pacquit V , Giglioll N , Bui V -L , Piere J N , Echevarria C , Vidal J 
Published: November 2023

Abstract
Leaves of C plants are characterized by concentrically organized photosynthetic tissues, i.e. an outer mesophyll (M) surrounding inner bundle sheath (BS) cells in which two metabolic cycles, the C and Calvin cycles, are working in concert to achieve CO assimilation. In ‘L-malate formers’, the primary fixation of CO (in its hydrated form) is carried out by the enzyme phosphoenolpyruvate carboxylase (E.C. 4.1.1.31, PEPC) in the cytoplasm ofM-cells to form oxaloacetic acid (OAA) which will be reduced to L-malate in the M chloroplasts; diffusive transport of Lmalate to BS-cells and its decarboxylation by NADP-malic enzyme in the chloroplast stroma make CO available for incorporation by ribulose bisphosphate carboxylase/oxygenase (Rubisco) in the Calvin cycle (Fig. 4.1) (Hatch 1987).
Protein phosphorylation and circadian rhythms
Authors: Nimmo H G , Carter P J , Fewson C A , Nimmo G A , Wiljins M B 
Published: November 2023

Abstract
Phosphoenolpyruvate carboxylase (PEPc) (EC 4.1.1.31) catalyses the fixation of CO (as HCO-) into oxaloacetate. It plays an anaplerotic role in nonphotosynthetic tissues and in the leaves of C plants. In the leaves of C plants it is located in the mesophyll tissue and catalyses the first committed step in the C pathway of CO assimilation (see, for example, Andreo et al. 1987). In this article, however, we concentrate on the regulation of PEPc in plants that perform Crassulacean acid metabolism (CAM). In CAM, PEPc is responsible for the nocturnal fixation of atmospheric CO; the oxaloacetate produced is reduced to malate which is stored as malic acid in the vacuole. During the following light period, the malate is released from the vacuole and decarboxylated, and the resulting CO is fixed in the Calvin cycle (Osmond and Holtum 1981). Consideration of the metabolic pathways involved in CAM suggests that mechanisms must exist to permit flux through PEPc at night and reduce or eliminate it during the day. In this article we describe the role of phosphorylation in the regulation of PEPc in leaves of the CAM plant Bryophyllum (Kalanchoii) fedtschenkoi.
The control of light-coupled leaf metabolism by reversible protein phosphorylation
Authors: Mackintosh C , Douglas P , Douglas F , Lillo C , Moorhead G 
Published: November 2023

Abstract
In green leaves, the primary products of photosynthetic electron transport in the chloroplast, namely ATP, NADPH, and reduced ferredoxin (Fdrect), are fed into many assimilatory and reductive pathways that are collectively known as ‘lightcoupled’ pathways (Anderson and Beardall 1991). Light-coupled pathways in the chloroplast include assimilation of CO into triose-P, reassimilation of photorespired NH, the assimilation of NO-into glutamate, and synthesis of many amino acids. In addition, light-generated ATP, NADPH, and/or Fd,ect support the export of reducing equivalents and phosphorylated compounds from the chloroplast to supply light-enhanced processes, such as sucrose biosynthesis and reduction of NO-, in the cytosol.
The role of phosphorylation in the regulation of phenylalanine ammonia-lyase
Authors: Bolwell G P , Davies D R , Gerrish C 
Published: November 2023

Abstract
One level of control of metabolic processes is mediated by the reversible phosphorylation of target proteins by protein kinases and phosphatases. These mechanisms are universal to all biological systems but only relatively recently has the extent of the involvement of such mechanisms in regulatory processes begun to be appreciated in plant systems. A number of protein kinases and protein phosphatases have now been characterized at the gene and protein levels in plants and some of their targets identified. The work described here concerns a key step in phenolic metabolism and phosphorylation events that might be involved in overall regulation of the phenylpropanoid pathway.