Search

Among important crops in Vietnam, we have to mention the coffee crop as the main cultivated crop in northwest area of the country, then we have to deal with the negative factor, or insect, coffee berry borer (CBB), which cause losses and damages for farmers with negatively significant impact. In previous studies, we isolated and identified five Beauveria bassiana strains of entomopathogenic fungus that damaged on coffee berry borer in local coffee fields of Son La province, Vietnam. The objective of this study continued to choose one of them for management CBB by autoinoculation trap. The result show that the virulence against CBB of the Bb5(MCB1) strain was highest (71.3 % confirmed mortality). Although 62.5% of CBB females that exposed to the Bb5(MCB1) fungus product with an average of 0,47 x 1012 conidia.gram-1 were able to penetrate the coffee berry exocarp, only 3.7% reached the endosperm. An autoinoculation trap containing the entomopathogenic fungus Bb was designed for the management of the CBB (trap TBU-AIT). Traps TBU-AIT baited with methanol and ethanol (1:1 ratio) mixtures at 868 mg day-1 attracted more insects than those traps baited at 452, 715 and 1050 mg day-1. We found a statistically-significant difference in average confirmed mortalities by fungus and by different field conditions in the period between 0 - 63 days setting traps TBU-AIT. Altogether, these results and relatively low production costs these auto-infection system can be recommended for integrated pest management on coffee auto-infection trap.

Auto-infection (infection arising from inoculum produced on the same host unit) is common in polycyclic plant pathogens, but often neglected in experimental and theoretical studies, which focus instead on infection of new hosts (allo-infection). Here we test the hypothesis that high auto-infection, as observed for leaf infecting fungal pathogens, could select for short latent periods. An individual-based simulation model keeps track of lesions, resulting from the spread of spores, between and within individual leaves. Linked to a trade-off between latent period and spore production capacity, as observed for Puccinia triticina on wheat, the adaptation of the latent period is analysed for different levels of auto-infection using the methods of pairwise invasibility plots. Results suggest that increased auto-infection selects for reduced latent periods. A reduction in leaf longevity also selects for reduced latent periods, which is most obvious for a relatively low ratio of auto- to allo-infection. This study is the first to consider the effect of auto-infection on the evolution of pathogen life history traits. The fact that auto-infection could drastically reduce pathogen latent periods highlights the need for more research in this area.

International audience; Fungal plant pathogens, especially rust fungi (Pucciniales), are well known for their complex life cycles, which include phases of sexual and asexual reproduction. The effect of asexual multiplication on population genetic diversity has been investigated in the poplar rust fungus Melampsora larici-populina using a nested hierarchical sampling scheme. Four hierarchical levels were considered: leaf, twig, tree and site. Both cultivated and wild poplar stands were sampled at two time points at the start and end of rust epidemics. A total of 641 fungal isolates was analysed using nine microsatellite markers. This study revealed that the genetic signature of asexual multiplication in the wild poplar stand was seen only at lower hierarchical levels (leaf and twig). Moreover, we observed an erosion of clonal structure through time, with an increase in both gene and genotypic diversity. New genotypes contributed to host infection over time, which demonstrates the importance of allo-infection in the epidemic process in this host-pathogen system. Compared with the wild stands, the nearly lack of detection of clonal structure in the cultivated stands reflects the higher infection level on cultivated poplars. More generally, this genetic analysis illustrates the utility of population genetics approach for elucidating the proportion of asexual reproduction in the multiplication of isolates during an epidemic, and for proper quantification of asexual dispersal in plant pathogens.

Cysticercosis is one of the ancient parasitic infections and endemic in many parts of the developing world. Humans acquire cysticercosis when they ingest pork tapeworm eggs either through faecal-oral route by eating faecally contaminated food or by auto infection. The clinical picture largely depends on the location of larval encystment. Neurocysticercosis is the most common form of presentation. Solitary extra neural lesions are quite rare and fairly small in size. We present a very unique case of 56 year old Malawian female with a very rare, long standing gigantic solitary cysticercosis pseudo tumour of the neck. By far, there is no documented report on incorrigible cysticercosis lesion with such a sheer size. Solitary extraneural cysticercosis lesions may mimic other soft tissue masses; therefore it is important for clinicians working in endemic regions to consider cysticercosis as a differential diagnosis when evaluating patients with soft tissue lesions.

National audience; Carrot cavity spot is caused by a complex of pathogens belonging to the genus Pythium, including Pythium violae. The disease is characterized by the appearance of sunken elliptical lesions on the taproot. The objective of the present study is to identify, understand, and prioritize the processes that induce the spatio-temporal kinetics of epidemics of cavity spot. We favoured the hypothesis that considers primary infection (from soilborne inoculum) and secondary infection (root-to-root contaminations from existing lesions, i.e., auto- and allo-infections). Epidemics were obtained during a 3-year field experiment after artificial soil infestation of plots with P. violae at increasing inoculum doses. Different kinetics of cavity spot were described using standardized disease measurements. The analysis of the incidence curves showed the early appearance of a plateau, with differences in the disease level that are positively correlated with the inoculum doses. These differences disappeared at the end of the cropping season. Three simulation models, integrating or not the concomitance of the primary and secondary infections, were fitted to the disease incidence to test if progress curves were compatible with the hypothesis of the occurrence of both infection processes: the logistic model, the bilogistic model of Hau and Amorim, and the model of Brassett and Gilligan without temporal decline of the soil inoculum potential. The quality of the fitting was correct in the three cases, and the hypothesis of the occurrence of secondary infections was not refuted. This result is an important argument to demonstrate the polycyclic nature of the disease.; Un complexe d'agents pathogènes du genre Pythium, incluant le Pythium violae, est responsable de la maladie de la tache de la carotte. Cette maladie est caractérisée par l'apparition de lésions en creux elliptiques sur le pivot racinaire. L'objectif de la présente étude est d'identifier, comprendre et hiérarchiser les processus épidémiologiques déterminant la dynamique spatio-temporelle de cette maladie. L'hypothèse de travail repose sur l'occurrence d'infections primaires (à partir de l'inoculum du sol) et secondaires (contaminations de racine à racine à partir de lésions existantes, c.-à-d. auto- et allo-infections). Des épidémies ont été reproduites au champ, au cours de trois années d'expérimentation, par l'infestation de microparcelles avec du P. violae à des doses croissantes. Les différentes cinétiques de la maladie ont été décrites avec des variables standardisées. L'analyse des courbes d'incidence a révélé l'apparition assez précoce d'un plateau, pour lequel des différences dans l'intensité des attaques ont été positivement corrélées à la dose d'inoculum; ces différences se sont atténuées en fin de cycle cultural. Pour vérifier si l'hypothèse de l'occurrence d'infections primaires et secondaires était compatible avec la forme de ces courbes, trois modèles ont été ajustés aux incidences de maladie, chacun d'eux intégrant ou non la concomitance des deux processus : le modèle logistique, le modèle bilogistique de Hau et Amorim, et le modèle de Brassett et Gilligan sans décroissance temporelle du potentiel d'inoculum primaire. La qualité d'ajustement des trois modèles a été correcte et n'a pas conduit à réfuter l'hypothèse de l'occurrence d'infections secondaires. Ce résultat constitue un argument important en faveur de la démonstration de la nature polycyclique de la maladie.

version n°4, février 2009imprimable en recto verso; The identification of pathways that induce the development of epidemics is a crucial step in the conception and the optimisation of control methods against plant diseases. The development of soil-borne plant diseases is due to epidemiological mechanisms closely dependent on the pathogen life history traits. Such mechanisms can be best investigated in vulnerable agrosystems, such as vegetable field crops, where short rotations and high inputs favour the emergence of severe disease problems. In carrots, one of the major sanitary problems is cavity spot, a root disease caused by a complex of Pythium spp. which affects root quality in several production basins in France and worldwide. The objectives of the present research were to identify, understand and hierarchise the processes that induce the spatio-temporal kinetics of carrot cavity spot epidemics. Interactions between species during the infectious stage can be neglected and disease progress curves were supposed to be not affected by changes in the diversity of the complex of Pythium species. The occurrence of primary and secondary infections was demonstrated and quantified experimentally for the first time in this pathosystem. The analysis of pathometric relationships between disease assessment variables (disease incidence, lesion density, symptom intensity, and total disease area) and the fitting of simulation models to observed epidemiological data confirmed the occurrence of both types of infections. An epidemiological model was elaborated, based on the processes quantified experimentally. The effect of different factors, such as soil moisture, seed density and timing of fungicide applications, on these epidemiological processes was tested. Finally, several scenarios combining control methods for integrated pest management of carrot cavity spot were designed and their optimisation discussed.; Le développement de maladies d'origine tellurique relève de mécanismes épidémiologiques particuliers, propres au cycle biologique et aux traits d'histoire de vie des agents pathogènes incriminés. La caractérisation des processus qui déterminent le développement des épidémies est une étape clé dans la conception et l'optimisation de méthodes de protection contre ces maladies. Les cultures légumières de plein champ constituent des agrosystèmes particulièrement sensibles aux attaques parasitaires. Les Pythium sont responsables du cavity spot de la carotte, une maladie racinaire qui affecte la qualité des récoltes dans plusieurs bassins de production en France et dans le monde. L'objectif des recherches présentées ici est d'identifier, comprendre et hiérarchiser les processus déterminant la dynamique spatio-temporelle de cette maladie, essentiellement due à Pythium violae, en association avec d'autres espèces du complexe parasitaire. L'analyse de la composition d'un de ces complexes, complétée par la caractérisation biologique des principales espèces pathogènes, suggère que par souci de simplification, il est raisonnable de négliger les interactions entre espèces au cours de la phase infectieuse. L'existence d'infections secondaires (auto- et allo-infections) chez P. violae, et donc la nature polycyclique d'une épidémie de cavity spot, sont démontrées expérimentalement. Cette hypothèse est initialement étayée par deux étapes de l'analyse, l'une portant sur l'examen de relations pathométriques, et l'autre sur les ajustements de modèles aux données illustrant des cinétiques de la maladie. L'ensemble des résultats obtenus permet de concevoir un modèle épidémiologique exploratoire, basé sur l'occurrence des infections primaires et secondaires. Les effets de différents facteurs sur ces processus, comme l'application d'un fongicide, l'humidité du sol et la densité de semis, sont testés expérimentalement et discutés. Ils permettent d'envisager l'association de moyens de lutte complémentaires dans le cadre de stratégies de protection intégrée.

Recent work on the virus diseases of the potato has not only led to a reconsideration of the relation between virus infection and the clinical picture of disease, but has furnished us with evidence as to the existence of two distinct viruses and their co-existence in certain diseases whether patent or carried. The present work deals with still another, a third element, the analysis and the synthesis of certain virus diseases from these elements, and the relations subsisting between the viruses when present together within one and the same plant.

I greatly appreciate the honour which the Society has done me in asking me to read a paper by way of introducing a general discussion on the treatment of mental disorders. My remarks will deal with the relationship of physical disorder to mental symptoms. The main point to which I will more particularly draw your attention is to the need for a closer study of the extent to which mental symptoms are the result of some auto-intoxication or infection from one or other of the free mucous surfaces of the body, the gastro-intestinal tract being, in virtue of its size and function, the most important channel. If the relationship is a close one our outlook on mental disorders necessitates greater attention being directed to the investigation and treatment of our patients with the aid of modern methods, than has hitherto been done. The literature of the subject contains many references of a general kind to what is called the toxic factor in the ætiology of insanity, but the systematic investigation of mental disorders from this point of view has not yet been carried out with the reasonable degree of completeness which modern medicine demands. In this connection it is right to refer to the valuable and suggestive work carried out by Lewis Bruce many years ago, the probable significance and value of which has, I think, been largely lost sight of. There is little new in the conception of the aetiology and treatment of mental disorders, which I am going to present for your consideration. It is, however, largely new in the sense that it has not yet been adequately tested. Prof. Robertson has lately drawn my attention to the interesting fact that the leading alienists in France more than 100 years ago entertained the view that the primary cause of mental disorders was to be found in visceral changes. Pinal in his classical text-book on mental disorders in 1809 wrote as follows:“It seems that the primitive seat of insanity generally is in the region of the stomach and intestines, and it is from that centre that the disorder of intelligence propagates itself as by a species of irradiation.”

In popular estimation there is no surer relief from itching than by scratching. The lower classes have no better remedy for anger than cursing. The more educated indulge in reproaches and complaints often referring to other causes than the immediate source of irritation. Experience, however, has taught us that, in only too many instances, the practices thus indulged in are positively deleterious; and that abnormal feeling is further aggravated by giving way to these impulses of reflex action. Still, there is a momentary relief, and a feeling of comfort which in a great number of cases is all that can be expected by the physician.

It is some eight or ten weeks ago since I had the privilege of enjoying the hospitality of your genial secretary, and in an unguarded moment, doubtless stimulated by my host's genial company, I half committed myself to giving a further communication on this subject, and he committed me for the other half. The truth is I have no paper to read. I have very little further to add to what I have said before, and I have certainly nothing further of note worth publishing. At the same time I very gladly welcome the opportunity of reviewing the position, so far as it appears to me in the light of the further available records on the subject in the last two years.

In 1886 I described to the Royal Society a substance, one of the most noticeable features of which was that it caused intravascular clotting when injected into the circulation of an animal. In subsequent publications I have further described the action of this substance, or rather group of allied substances, and speak of them as fibrinogens. In particular, I pointed out in my papers in du Bois-Reymond’s ‘Archiv,’ 1886, and in Ludwig’s ‘Festschrift,’ 1887, that the lymph and chyle contained this substance.

Two species of fish-eating bird namely, Amaurornis phoenicurus and Ardeola bacchus were fed with infective larvae of Capillaria philippinensis in Gambusia holbrookii. Intestinal capillariasis was able to establish in all three A. phoenicurus and one of three A. bacchus. Prepatent period in A. phoenicurus ranged from 22 to 30 days, whereas in A. bacchus it was 16 days after infection. Auto-infection was observed in all susceptible birds and the protective immunity had developed in one of A. phoenicurus used.

n/a

The present is preeminently the time of the study of the etiology of disease, just as the past has been characterized by an almost exhaustive study of anatomy, physiology and pathology. In this connection the subject of infection has been the most profitable, as it hae been the most interesting of all investigations; most interesting because little by little it has brought to light the knowledge of microorganisms that produce diseases, the causation of which was hitherto inexplicable; profitable because it has and will result in the discovery of the conditions that arrest their development and the agents that will neutralize their toxic influence. Infection from without we may safely say produces the various forms of meningitis, including cerebro-spinal meningitis, tetanus, hydrophobia, acute poliomyelitis, acute ascending paralysis, the puerperal and syphilitic diseases of the nervous system. The infections which arise from within are also important etiologic factors in developing diseases

It seems remarkable that with all the teliologic acumen of our profession, one of the principal causes of disease has been hitherto almost entirely overlooked—that of intestinal putrefaction, so palpable that it could not have been concealed; and it is more than probable that the largest proportion of fatalities have heretofore resulted, directly or indirectly, from that single cause. The idea is a simple cognition apart from any technical qualification; in other words, we have only to see and believe; for if we observe the natural process of digestion, assimilation and elimination we can not fail to perceive the inevitable morbid influence that must necessarily follow in the wake of delayed defecation. As soon as the mass of chyme emerges from the stomach, the elements of which it is composed begin to change their relations, and as it gradually passes down through the alimentary canal the nutritive combinations are absorbed

n/a

n/a

Auto-infection is not altogether a new subject, yet it has remained for modern bacteriology and chemistry to demonstrate its relation to, and importance in, the production of disease; and, today no subject commands greater interest or demands more serious thought and careful study, because when more thoroughly understood it will be found to be at the root and foundation of many of the so-called reflex and other obscure diseases. There are many sources of auto-intoxication, but this paper deals more especially with that variety of infection caused by the absorption of toxic substances generated within the alimentary canal by chemic, putrefactive or fermentative changes or bacterial development, aided and influenced by the existence of a pathologic condition of the rectum and contiguous structures. That I may more clearly elucidate the subject, it will be necessary to call attention to the fact that the physiologic processes of the abdominal and pelvic

A physician, aged 30, a graduate student, gave a positive reaction to the Schick test, Oct. 10, 1922. There was a very slight pseudoreaction. There was no history of previous diphtheria. October 25, he carried out a virulence test with a culture from a known clinical case of diphtheria. At this date, he had not himself been in contact with a known clinical case for some time; nor had he been working with any other diphtheria cultures. While inoculating the guinea-pig, he pricked the skin on the dorsum of the terminal phalanx of the left thumb with the needle of a syringe containing the suspension from a twenty-four hour Loeffler slant. The suspension in the syringe was from a culture from the above mentioned case, and caused typical diphtheric lesions in the guinea-pig. October 29, the patient visited the laboratory and examined the inoculated animal, but after this date he

The increasing knowledge of pathologic anatomy and pathogenic physiology tends to evolution in therapeutics affecting our remedial agents. We discover that they have more or less definite value; they have their rise and fall. The drug extolled today by high authority we find does not come up to the manifesto of the manufacturing chemist and may be obsolete tomorrow. When antifebrin was first introduced, a child was brought from New York City for treatment. Their physician had prescribed this drug in 2-grain doses, to be given every two hours if there should be a rise in temperature. After they had given it for a couple of days, the nurse noticed cyanosis and coldness of the extremities, with failing pulse. This fact was a valuable one to us. It is now found to have its effect as an antipyretic by depressing the heart, it has a directly paralyzing action upon the

To the Editor: —The report by Baldwin, McCallum and Doull (The Journal, May 12, p. 1375) of a case of pharyngeal diphtheria, probably due to auto-infection from a diphtheric lesion of the thumb, recalls a case that occurred in Durand Hospital, reported by Emge (The Journal, Aug. 7, 1915, p. 529). In this case an intern received an injury to his finger while performing an intubation for laryngeal diphtheria. The infection of the finger preceded the throat infection several days.

Clinical observers have described the characteristic phenomena of various neuroses; also of organic nerve lesions whose etiology can only be ascribed to auto-infection or intoxication resulting from non-elimination of the products of metabolism, or the absorption of ptomains arising from the action of the ever-present bacteria on the accumulations of retained excreta in the alimentary canal. Alienists have frequently called attention to the relation existing between a constipated or sluggish condition of the bowels and melancholia, dementia and depressed intellectual powers. It is the opinion of the writer, that the ptomains or toxins and toxalbumins arising from bad digestion and faulty elimination are greater factors in disease than has yet been stated by writers on this subject. For the purpose of bringing this subject before this society in such a manner as to elicit an intelligent discussion, let us first inquire into some of the physiologic acts of the digestive

An irregular type of fever incident to auto-infection is frequently found in artificially reared children. It is also encountered in young adolescence, and may be found in breast-fed children of irregular habits. When associated with a depressed system or unhygienic surroundings the fever is most likely to assume a more protracted and intermittent type. When found in breast-fed children, the fever is suddenly ushered in at a high grade (103 to 104 degrees), very frequently sustaining this elevation of temperature for several days, when it may break into an intermittent form. The fever associated with intestinal toxemia has many times led to the diagnosis of typhoid fever, from which it can only be discriminated in young children by a careful analysis of the various symptoms, conditions and surroundings, diet and exposure, and all the many complications incident to artificial management. The clinical picture of a child suffering from auto-infection so