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1.
Adv Genet ; 94: 41-65, 2016.
Article in English | MEDLINE | ID: mdl-27131322

ABSTRACT

The order Entomophthorales, which formerly contained c.280 species, has recently been recognized as a separate phylum, Entomophthoromycota, consisting of three recognized classes and six families. Many genera in this group contain obligate insect-pathogenic species with narrow host ranges, capable of producing epizootics in natural insect populations. Available sequence information from the phylum Entomophthoromycota can be classified into three main categories: first, partial gene regions (exons+introns) used for phylogenetic inference; second, protein coding gene regions obtained using degenerate primers, expressed sequence tag methodology or de novo transcriptome sequencing with molecular function inferred by homology analysis; and third, primarily forthcoming whole-genome sequencing data sets. Here we summarize the current genetic resources for Entomophthoromycota and identify research areas that are likely to be significantly advanced from the availability of new whole-genome resources.


Subject(s)
Fungi/pathogenicity , Genome, Fungal , Genomics/methods , Insecta/microbiology , Animals , Biological Evolution , Host-Pathogen Interactions , Phylogeny
2.
Insectes Soc ; 58(2): 145-151, 2011 May.
Article in English | MEDLINE | ID: mdl-21475686

ABSTRACT

Fungus gardens of the basidiomycete Leucocoprinus gongylophorus sustain large colonies of leaf-cutting ants by degrading the plant material collected by the ants. Recent studies have shown that enzyme activity in these gardens is primarily targeted toward starch, proteins and the pectin matrix associated with cell walls, rather than toward structural cell wall components such as cellulose and hemicelluloses. Substrate constituents are also known to be sequentially degraded in different sections of the fungus garden. To test the plasticity in the extracellular expression of fungus-garden enzymes, we measured the changes in enzyme activity after a controlled shift in fungal substrate offered to six laboratory colonies of Atta cephalotes. An ant diet consisting exclusively of grains of parboiled rice rapidly increased the activity of endo-proteinases and some of the pectinases attacking the backbone structure of pectin molecules, relative to a pure diet of bramble leaves, and this happened predominantly in the most recently established top sections of fungus gardens. However, fungus-garden amylase activity did not significantly increase despite the substantial increase in starch availability from the rice diet, relative to the leaf diet controls. Enzyme activity in the older, bottom sections of fungus gardens decreased, indicating a faster processing of the rice substrate compared to the leaf diet. These results suggest that leaf-cutting ant fungus gardens can rapidly adjust enzyme activity to provide a better match with substrate availability and that excess starch that is not protected by cell walls may be digested by the ants rather than by the fungus-garden symbiont. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00040-010-0127-9) contains supplementary material, which is available to authorized users.

3.
Mol Ecol ; 15(11): 3131-8, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16968259

ABSTRACT

All colonies of the fungus-growing termite Macrotermes natalensis studied so far are associated with a single genetically variable lineage of Termitomyces symbionts. Such limited genetic variation of symbionts and the absence of sexual fruiting bodies (mushrooms) on M. natalensis mounds would be compatible with clonal vertical transmission, as is known to occur in Macrotermes bellicosus. We investigated this hypothesis by analysing DNA sequence polymorphisms as codominant SNP markers of four single-copy gene fragments of Termitomyces isolates from 31 colonies of M. natalensis. A signature of free recombination was found, indicative of frequent sexual horizontal transmission. First, all 31 strains had unique multilocus genotypes. Second, SNP markers (n = 55) were largely in Hardy-Weinberg equilibrium (90.9%) and almost all possible pairs of SNPs between genetically unlinked loci were in linkage equilibrium (96.7%). Finally, extensive intragenic recombination was found, especially in the EF1alpha fragment. Substantial genetic variation and a freely recombining population structure can only be explained by frequent horizontal and sexual transmission of Termitomyces. The apparent variation in symbiont transmission mode among Macrotermes species implies that vertical symbiont transmission can evolve rapidly. The unexpected finding of horizontal transmission makes the apparent absence of Termitomyces mushrooms on M. natalensis mounds puzzling. To our knowledge, this is the first detailed study of the genetic population structure of a single lineage of Termitomyces.


Subject(s)
Basidiomycota/physiology , Isoptera/physiology , Animals , Base Sequence , Basidiomycota/genetics , Basidiomycota/growth & development , DNA, Fungal/chemistry , DNA, Fungal/genetics , DNA, Ribosomal Spacer/chemistry , DNA, Ribosomal Spacer/genetics , Female , Genetics, Population , Isoptera/microbiology , Male , Molecular Sequence Data , Peptide Elongation Factor 1/chemistry , Peptide Elongation Factor 1/genetics , Phylogeny , Polymerase Chain Reaction , Polymorphism, Single Nucleotide/genetics , RNA Polymerase II/chemistry , RNA Polymerase II/genetics , Sequence Analysis, DNA , South Africa , Symbiosis/physiology
4.
Postgrad Med ; 107(3): 203-7; quiz 277, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10728144

ABSTRACT

A diagnosis of IBS can often be established on the basis of the Manning and Rome criteria, which delineate specific features. A limited evaluation to exclude organic disease confirms this clinical impression. Patients should be reassured that no serious organic illness is causing the symptoms and should be educated about the natural history of the disorder. Treatment must be directed at both achieving control of the gastrointestinal complaints and searching for an underlying psychological or social factor that may contribute to the disorder.


Subject(s)
Colonic Diseases, Functional , Colonic Diseases, Functional/diagnosis , Colonic Diseases, Functional/etiology , Colonic Diseases, Functional/therapy , Humans
5.
Gastroenterol Clin North Am ; 27(4): 747-82, v-vi, 1998 Dec.
Article in English | MEDLINE | ID: mdl-9890113

ABSTRACT

Vasculitis can affect every organ of the digestive system. In many cases, it may first present with gastrointestinal symptoms. In several forms of vasculitis, including Churg Strauss syndrome, Henoch-Schönlein purpura, and lupus, the majority of patients have gastrointestinal involvement. The astute gastroenterologist should consider vasculitic causes of the symptoms seen in many patients. Making the correct diagnosis requires a thorough understanding of the potential role of vasculitis in causing these symptoms and the appropriate path to making a diagnosis. This article reviews the variety of manifestations of vasculitis on the digestive system, and emphasizes diagnosis and clinical manifestations.


Subject(s)
Digestive System Diseases/etiology , Gastrointestinal Diseases/etiology , Liver Diseases/etiology , Vasculitis/complications , Adrenal Cortex Hormones/adverse effects , Anti-Inflammatory Agents, Non-Steroidal/adverse effects , Humans , Methotrexate/adverse effects , Vasculitis/drug therapy
6.
Dig Dis Sci ; 42(2): 447-50, 1997 Feb.
Article in English | MEDLINE | ID: mdl-9052534

ABSTRACT

Although the incidence of syphilis is increasing, liver involvement in tertiary syphilis remains exceptional. We report a case of tertiary syphilis revealed by liver localization. The clinical picture was misleading, mimicking multinodular hepatic metastasis. The final diagnosis was suspected following a fine-needle ultrasound-guided biopsy of a liver nodule showing granulomas as well as acellular necrosis and confirmed by positive serum syphilitic reactions and the presence of spirochetes in the liver. The outcome was uneventful following antibiotic treatment. It is important to be aware of the misleading picture of the disease, which has a favorable prognosis provided that simple treatment is rapidly initiated.


Subject(s)
Liver Diseases/diagnosis , Syphilis/diagnosis , Female , Humans , Liver Diseases/drug therapy , Liver Diseases/pathology , Middle Aged , Syphilis/drug therapy , Syphilis/pathology
7.
J Neuroimaging ; 6(4): 250-4, 1996 Oct.
Article in English | MEDLINE | ID: mdl-8903081

ABSTRACT

A 21-year-old woman presented with a 5-month history of meningeal signs and evidence of intracranial hypertension and, as shown by magnetic resonance imaging (MRI), progressively more extensive meningeal enhancement, particularly within the spinal canal. Autopsy disclosed the presence of primary diffuse leptomeningeal gliomatosis with spinal cord predominance, possibly arising within heterotopic leptomeningeal glial tissue in the cervical region. No parenchymal primary lesion was identified. MRI with gadolinium appears to be the imaging modality of choice for the early detection of primary diffuse leptomeningeal neoplasia.


Subject(s)
Arachnoid/pathology , Glioma/diagnosis , Magnetic Resonance Imaging , Meningeal Neoplasms/diagnosis , Meninges/pathology , Pia Mater/pathology , Pseudotumor Cerebri/diagnosis , Adult , Choristoma/pathology , Contrast Media , Fatal Outcome , Female , Gadolinium , Glioma/pathology , Humans , Image Enhancement , Meningeal Neoplasms/pathology , Neuroglia/pathology , Pseudotumor Cerebri/pathology , Spinal Canal/pathology
8.
Prim Care ; 23(3): 525-34, 1996 Sep.
Article in English | MEDLINE | ID: mdl-8888342

ABSTRACT

Acute and chronic pancreatitis present challenging problems for the physician. In acute pancreatitis, initial efforts should be directed toward supporting the patient hemodynamically. Recognition and early treatment of complications such as shock, renal failure, respiratory failure, hypocalcemia, abscess, hemorrhage, or unremitting symptoms caused by an impacted stone in the common bile duct are necessary. The cause of the pancreatitis must be identified, possibly for acute therapy, but certainly to prevent recurrences and progression of disease. In chronic pancreatitis, insufficiencies of pancreatic function must be identified and consequent malabsorption and diabetes treated appropriately. The major challenge is the relief of chronic pain. It is hoped that this can be accomplished medically, but in carefully selected cases, specific types of surgery may be required.


Subject(s)
Pancreatitis/diagnosis , Acute Disease , Chronic Disease , Humans , Pancreatitis/complications , Pancreatitis/therapy , Prognosis
9.
Am J Gastroenterol ; 90(6): 1000-1, 1995 Jun.
Article in English | MEDLINE | ID: mdl-7771393

ABSTRACT

A 26-yr-old woman presented with odynophagia, dysphagia, and intermittent bloody stools. Clinical, endoscopic, and microscopic evidence confirmed the diagnosis of severe Crohn's disease of the oropharynx, esophagus, proximal stomach, terminal ileum, and colon.


Subject(s)
Crohn Disease , Esophageal Diseases , Adult , Crohn Disease/diagnosis , Crohn Disease/pathology , Esophageal Diseases/diagnosis , Esophageal Diseases/pathology , Female , Humans
11.
Gastroenterol Clin Biol ; 18(1): 81-3, 1994.
Article in French | MEDLINE | ID: mdl-8187995

ABSTRACT

Malformations of extrahepatic portal vein are rare. We report a case of extrahepatic portal vein aneurysm which was incidentally found in a female patient, aged 67, suffering from alcoholic cirrhosis. This malformation was located at the portal bifurcation and presented ultrasonically as an oval, non-echogenic, parahilar mass, 38 mm in diameter, and in continuity with the portal trunk. On CT-scan and angiography, diagnosis of portal vein aneurysm located at its extrahepatic segment was confirmed. The cause of extrahepatic portal vein aneurysm remains controversial. A congenital and/or acquired origin induced by portal hypertension explains their development.


Subject(s)
Aneurysm/etiology , Arteriovenous Malformations/complications , Portal Vein/abnormalities , Aged , Aneurysm/diagnostic imaging , Arteriovenous Malformations/diagnostic imaging , Female , Humans , Hypertension, Portal/complications , Liver Cirrhosis, Alcoholic/complications , Portography , Tomography, X-Ray Computed , Ultrasonography
12.
Gastroenterol Clin Biol ; 17(5): 334-40, 1993.
Article in French | MEDLINE | ID: mdl-8349067

ABSTRACT

The efficacy of lansoprazole (30 mg/d) and omeprazole (20 mg/d) has been assessed in active duodenal ulcer disease in 144 patients included in a multicentric, randomized, double-blind trial. After two weeks, the healing rates were 74% and 58% in the lansoprazole and omeprazole groups, respectively (P = 0.049). After 4 weeks, the healing rates were 94% in each group (NS). The delay to pain relief was 2 days for lansoprazole and 3 days for omeprazole (NS). Minor side effects occurred in 12% of the lansoprazole treated patients and in 13% of the omeprazole treated patients. No severe adverse events were reported. A slight increase in serum gastrin level was observed, similar in both groups (+35 UI/L and +19 UI/L for lansoprazole and omeprazole respectively). This study confirms previous results concerning the efficacy of both treatments in duodenal ulcer disease. The statistical difference observed for healing rates after 2 weeks could correspond to a faster efficacy for lansoprazole (30 mg) than for omeprazole (20 mg).


Subject(s)
Anti-Ulcer Agents/therapeutic use , Duodenal Ulcer/drug therapy , Omeprazole/analogs & derivatives , Omeprazole/therapeutic use , 2-Pyridinylmethylsulfinylbenzimidazoles , Administration, Oral , Adult , Anti-Ulcer Agents/administration & dosage , Double-Blind Method , Duodenal Ulcer/blood , Duodenal Ulcer/complications , Female , Gastrins/analysis , Humans , Lansoprazole , Male , Middle Aged , Omeprazole/administration & dosage , Pain/drug therapy , Pain/etiology
14.
Ann Gastroenterol Hepatol (Paris) ; 27(5): 231-3, 1991 Oct.
Article in French | MEDLINE | ID: mdl-1746877

ABSTRACT

To study clinical and biological tolerability, 114 chronically constipated patients of both sexes, aged 18-70, without any organic alteration of the colon, received lactitol over a period of one or two months. Clinical tolerability was found to be good by 80 per cent of patients and biological tolerability excellent. Clinical efficacy was found correct for 80 per cent of patients with a dosage of 20 g (single dose in the evening). All patients, except one, agreed with the packaging and the taste of the product.


Subject(s)
Constipation/drug therapy , Sugar Alcohols/therapeutic use , Adolescent , Adult , Aged , Constipation/psychology , Female , Humans , Male , Middle Aged , Patient Satisfaction , Sugar Alcohols/administration & dosage , Sugar Alcohols/adverse effects
16.
Ann Pathol ; 9(1): 57-61, 1989.
Article in French | MEDLINE | ID: mdl-2712872

ABSTRACT

The authors report a case of a primary melanoma of the esophagus, which is a rare neoplasm with poor prognosis. The diagnosis of malignant melanoma was suggested, on endoscopic biopsies, because of the presence of large malignant cells with abundant cytoplasm containing melanin pigment positive in the Fontana-Masson's reaction. These cells were immunoreactive for S100 protein while they did not show staining for antiepithelial membrane antigen and anti-keratin antibodies. Moreover ultrastructural study of the tumor cells revealed cytoplasmic aberrant premelanosomas. An important histological feature of the present case, which confirmed the primary oesophageal nature of the tumor was the presence of foci of melanosis (benign melanocytes) within the oesophageal epithelium which was adjacent to the melanoma. The variation in the histology of malignant melanoma may provide difficulties in diagnosis especially if one is limited to study a small biopsy specimen. In such cases other diagnoses including epidermoid carcinoma with prominent spindle-cell features and sarcomas should be eliminated by means of immunohistochemical and ultrastructural studies. The particular feature of our case, which apparently has not been reported previously, is the identification of the melanosis two years prior to the diagnosis of the malignant melanoma. The present study indicates that the identification of this lesion is of important diagnostic interest and might lead to the follow-up surveillance of the melanosis by multiple biopsies.


Subject(s)
Esophageal Neoplasms/pathology , Melanoma/pathology , Melanosis/pathology , Esophageal Neoplasms/analysis , Esophageal Neoplasms/ultrastructure , Humans , Male , Melanoma/analysis , Melanoma/ultrastructure , Microscopy, Electron , Middle Aged
19.
Hepatology ; 4(4): 671-7, 1984.
Article in English | MEDLINE | ID: mdl-6745856

ABSTRACT

Primary biliary cirrhosis is infrequently diagnosed in men, so that the clinical, biochemical and histopathological spectrum of this disease in men has not been evaluated. Therefore, we studied 30 men who had a histological diagnosis of primary biliary cirrhosis and had positive tests for antimitochondrial antibodies. Five patients had no hepatobiliary symptoms, and two of these patients had neither biochemical nor histological evidence of cholestasis. These 30 male patients' findings were compared with the findings in 30 age-matched women who also had primary biliary cirrhosis and antimitochondrial antibodies. Six of these patients were asymptomatic. Clinical findings and symptomatic status, in addition to biochemical and histopathological features, were generally similar in both male and female patients. The possible significance of higher serum alkaline phosphatase activities and lower frequency of occurrence of piecemeal necrosis in men with primary biliary cirrhosis, as compared with women, requires further study.


Subject(s)
Liver Cirrhosis, Biliary/physiopathology , Liver/pathology , Sex Characteristics , Adult , Aged , Autoantibodies/analysis , Bile Ducts/pathology , Bilirubin/blood , Cholestasis/etiology , Female , Humans , Liver Cirrhosis, Biliary/complications , Liver Cirrhosis, Biliary/pathology , Male , Middle Aged , Mitochondria, Liver/immunology
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