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R Reimschuessel

Publications and source records attributed to R Reimschuessel.

17 recordsLinked to original sources
PubMed1999

Pathogenicity of Mycobacterium fortuitum and Mycobacterium smegmatis to goldfish, Carassius auratus.

Despite the ubiquitous presence of atypical mycobacteria in the environment and the potential risk of infection in humans and animals, the pathogenesis of diseases caused by infection with atypical mycobacteria has been poorly characterized. In this study, goldfish, Carassius auratus were infected either with the rapidly growing fish pathogen, Mycobacterium fortuitum or with another rapidly growing mycobacteria, Mycobacterium smegmatis. Bacterial persistence and pathological host response to mycobacterial infection in the goldfish are described. Mycobacteria were recovered from a high percentage of inoculated fish that developed a characteristic chronic granulomatous response similar to that associated with natural mycobacterial infection. Both M. fortuitum and M. smegmatis were pathogenic to fish. Fish infected with M. smegmatis ATCC 19420 showed the highest level of giant cell recruitment compared to fish inoculated with M. smegmatis mc(2)155 and M. fortuitum. Of the three strains of mycobacteria examined, M. smegmatis ATCC 19420 was the most virulent strain to goldfish followed by M. fortuitum and M. smegmatis mc(2)155, respectively.

Animals↗
PubMed1999

Superoxide production in phagocytes obtained from Mycobacterium marinum-stimulated goldfish (Carassius auratus) that were exposed to copper.

OBJECTIVE: To investigate the effects of copper exposure and recovery from copper toxicosis on the nonspecific immune response in Mycobacterium marinum-inoculated goldfish. ANIMALS: Goldfish (Carassius auratus) with a mean weight of 33.5 g. PROCEDURE: Superoxide (O2-) production was measured in fish 2 to 6 weeks after injection with phosphate-buffered saline (PBS) solution or M marinum (10(2) to 10(7) colony-forming units [CFU]/fish). Then, paired groups of fish were injected with PBS solution or 10(4) CFU of M marinum and exposed to copper (100 microg/L) for 7 days or for 4 days with 3 days of recovery. One paired group not exposed 14 days later to copper served as control fish. Phagocyte production of O2-was measured by use of the nitroblue tetrazolium reduction assay. Inflammation and bacterial colony counts were determined by use of routine histologic and microbiologic procedures. RESULTS: Superoxide production achieved a maximal response 2 to 4 weeks after M marinum inoculation. Compared with control fish, O2- production increased in the groups exposed to copper but then decreased in the exposed groups that were allowed to recover. Superoxide response and peritoneal inflammation were greater in M marinum-inoculated groups than in non-inoculated groups. CONCLUSIONS: Copper exposure and inoculation with M marinum increased O2- production, whereas recovery after exposure decreased O2- production, even in fish that were immunostimulated by M marinum. CLINICAL RELEVANCE: When the antimicrobial oxidative response is suppressed after copper exposure, steps should be taken to avoid imposing additional stress and minimize the possibility of resurgent or secondary pathogenic infections.

Animals↗
PubMed1998

Goldfish, Carassius auratus, a novel animal model for the study of Mycobacterium marinum pathogenesis.

We have developed an animal model for studying mycobacterial pathogenesis using Mycobacterium marinum and the goldfish, Carassius auratus. Goldfish are injected intraperitoneally with doses between 10(2) and 10(9) CFU of M. marinum organisms. Depending on the dose of M. marinum organisms administered, an acute or chronic disease is produced. The acute disease is characterized by systemic mycobacterial infection, severe peritonitis, tissue necrosis, and a short median survival time. The chronic disease is characterized by granuloma formation in all organs and survival of animals to the end point of the experiment (56 days). Colony counts in organ homogenates showed recovery of mycobacteria from a high percentage of inoculated animals. We believe this well-characterized animal model will be useful for studying mycobacterial pathogenesis.

Acute Disease↗
PubMed1998

Abdominal ascites in electric eels (Electrophorus electricus) associated with hepatic hemosiderosis and elevated water pH.

Six electric eels (Electrophorus electricus) from various centers that house aquatic organisms presented clinically with abdominal distension following prolonged exposure to elevated environmental pH. Postmortem examination revealed marked ascites. Culture of the abdominal fluid from three of the eels yielded either Aeromonas hydrophila or Citrobacter freundii, which were most likely secondary invaders. Histopathology showed marked iron accumulation in both hepatocytes and hepatic macrophage aggregates.

Animals↗
PubMed1998

Fish lesions in the Chesapeake Bay: Pfiesteria-like dinoflagellates and other etiologies.

Ulcerative lesions and mass mortalities of Atlantic estuarine fish, particularly menhaden (Brevoortia tyrannus), have been associated with exposure to Pfiesteria-like dinoflagellates and their toxins. We collected fish from the Chicamacomico River, Maryland, and observed solitary ulcerative lesions on the majority of menhaden sampled. One striped bass (Morone saxatilis) had an area of reddening around the base of the dorsal fin. Bluegill (Lepomis machrochirus), channel catfish (Ictalurus punctatus), yellow perch (Perca flavescens), and carp (Cyprinus carpio) were externally nonremarkable. Histologically ulcerative menhaden lesions demonstrated marked chronic inflammatory infiltrate in large areas of exposed necrotic muscle. The ulcers contained granulomata with fungal hyphae in the necrotic tissue. Gram negative rod-shaped bacteria were also observed in the lesions, a common finding in ulcers of aquatic organisms. Our data suggest that typical ulcerative lesions observed on fish from areas of Pfiesteria-like dinoflagellate blooms are reflective of dermatosis, which may be related to a variety of individual or combined environmental stressors. Exposure to dinoflagellate toxin)s) potentially represents one such stressor. The role of Pfiesteria-like dinoflagellate toxin in fish primary lesion development is currently under investigation.

Animals↗
PubMed1997

Identification of mycobacteria infecting fish to the species level using polymerase chain reaction and restriction enzyme analysis.

An assay is described utilizing PCR technology for a rapid diagnostic test to identify fish infection with Mycobacterium marinum, M. fortuitum and M. chelonae. A 924 bp DNA fragment from a highly conserved area of the mycobacterial 16S rRNA gene was amplified using mycobacteria genus-specific primers and digested with restriction enzymes (BanI and ApaI). This examination yielded unique restriction patterns for each mycobacterial specie enabling identification of mycobacteria infecting fish to the species level. The protocol can be applied to purified DNA, a simple colony preparation or infected fish tissue. This protocol can be completed in 1-2 days.

Animals↗
PubMed1996

Evaluation of gentamicin-induced nephrotoxicosis in toadfish.

OBJECTIVE: To evaluate the nephrotoxic effects of various dosages and regimens of gentamicin in kidneys of toadfish (Opsanus tau). DESIGN: Prospective, randomized, controlled trial. ANIMALS: 45 clinically normal toadfish. PROCEDURE: Gentamicin was administered at dosages of 2.5, 5, 15, and 50 mg/kg of body weight, i.p., and 3.5 mg/kg, i.m. Fish were euthanatized at various periods (2, 3, 7, 14, and 28 days) after gentamicin administration. Four hours prior to euthanasia, each fish received 100 mg of bromodeoxyuridine/kg, i.p. Histologic evaluation for signs of toxicosis was performed on samples of renal tissue. RESULTS: Extensive necrosis was evident in the proximal tubes in each fish injected with gentamicin at every time period, regardless of route of administration. By 28 days after injection of gentamicin, sections of kidney that were examined were essentially devoid of proximal tubules. Bromodeoxyuridine staining was detected in collecting duct epithelial cells, but repair along nephrons was not observed. CLINICAL IMPLICATIONS: Toadfish kidneys are extremely susceptible to gentamicin-induced nephrotoxicosis. Fish in this study did not have overt clinical signs of nephrotoxicosis, but sustained massive tubular necrosis when given the exact therapeutic dose that has been used for channel catfish. There are substantial risks of inducing iatrogenic renal injury in fish species for which therapeutic dosages of gentamicin have not been determined.

Animals↗
PubMed1996

Transgenic fish and its application in basic and applied research.

Since 1985, transgenic fish have been successfully produced by microinjecting or electroporating desired foreign DNA into unfertilized or newly fertilized eggs using many different fish species. More recently, transgenic fish have also been produced by infecting newly fertilized eggs with pantropic, defective retroviral vectors carrying desired foreign DNA. These transgenic fish can serve as excellent experimental models for basic scientific investigations as well as in biotechnological applications. In this paper, we will review the current status of the transgenic fish research and its potential application in basic and applied research.

Animals↗
PubMed1995

Development of new nephrons in adult kidneys following gentamicin-induced nephrotoxicity.

Gentamicin-induced nephrotoxicity results in necrosis of proximal tubular epithelial cells. In mammals, the injured nephron can be repaired by migration and division of surviving cells. We examined this repair process in the fresh-water goldfish, Carassius auratus. Fish were given a single intraperitoneal injection of 50 mg/kg gentamicin and sacrificed at 1, 4, 14, and 21 days. Injured nephrons showed regeneration along the basement membrane several days following gentamicin administration. In addition, 2-3 weeks following the injection, entirely new nephrons formed in the renal interstitium. Development of new nephrons in adult fish kidneys provides an excellent model for studying renal development and toxicity, and could provide insights into new therapies for chronic renal disease.

Analysis of Variance↗
PubMed1993

Epidemic misuse.

Explore the source record for details and available documents.

Animals↗
PubMed1993

Parasitic meningoencephalitis in nurse sharks (Ginglymostoma cirratum).

Based on microscopic examination of the brains of seven wild-caught nurse sharks (Ginglymostoma cirratum), we observed a severe meningoencephalitis associated with numerous parasitic granulomas. The parasites were larval nematodes with morphological characteristics of the Superfamily Dracunculoidea. Although meningeal larval aggregates were associated with chronic inflammation, additional parasitic nodules found on the endocardial surface and perimandibular region did not provoke an inflammatory response. Neither the route of infection nor life cycle were determined.

Animals↗
PubMed1990

Octopus automutilation syndrome.

This paper describes an automutilation syndrome (OAS) in three species of captive octopuses, Octopus dolfleini, O. bimaculoides, and O. maya, characterized by external arm and mantle lesions. Three clinical patterns in nine animals had similar and characteristic gross and histopathologic features. Axial nerve or brachial artery lesions were observed in six of the nine cases and vascular lesions were seen in two of eight cases with mantle ulcerations. A relationship between automutilation in the octopus and dysesthesias due to neural or vascular pathology is proposed.

Animals↗
PubMed1990

Myocarditis in the common cuttlefish (Sepia officinalis).

This report describes five cases of myocarditis in the common cuttlefish, Sepia officinalis. Both the systemic heart and the branchial hearts exhibited inflammatory lesions. Vibrio species were isolated from four of these cases.

Animals↗
PubMed1990

Development of newly formed nephrons in the goldfish kidney following hexachlorobutadiene-induced nephrotoxicity.

New nephrons developed in goldfish, Carassius auratus, several weeks following hexachlorobutadiene-induced (HCBD) nephrotoxicity. Basophilic clusters of presumptive nephrogenic cells incorporated 5-bromo, 2'deoxyuridine (BrdU) one week after HCBD injection, indicating initiation of DNA synthesis. These clusters, like renal vesicles in the developing kidney, elongated, fused with collecting ducts and developed into immature nephrons during the next 2 weeks. Stereologic quantification showed the volume percent of the kidney occupied by the developing nephrons was greater in HCBD-treated fish 2, 3, 4, and 10 weeks after injection than in the control fish. The presence of large numbers of developing nephrons may provide a marker for renal injury in fish from contaminated waterways.

Animals↗
PubMed1988

Tropical fish medicine. Necropsy examination of fish.

Necropsy examination of moribund or dead specimens is an essential step in diagnosing fish diseases. This article discusses basic anatomy and necropsy procedures. A large part of the article has been devoted to methods of procuring samples for laboratory analysis and histologic examination. To determine which findings are responsible for the mortalities, the entire case history and gross necropsy findings must be reviewed. Careful observations made during the necropsy examination provide valuable information immediately, as well as later on in the interpretation of laboratory data.

Animals↗
PubMed1981

A soluble alkaline phosphatase from Bacillus licheniformis MC14. Histochemical localization, purification, characterization and comparison with the membrane-associated alkaline phosphatase.

Growth conditions affect the quantity and distribution of alkaline phosphatase (orthophosphoric-monoester phosphohydrolase (alkaline optimum), EC 3.1.3.1) in Bacillus licheniformis MC14. The soluble alkaline phosphatase, which has been found in biochemical localization studies between the cell wall and cell membrane (Glynn, J.A., Schaffel, S.D., McNicholas, J.M. and Hulett, F.M. (1977) J. Bacteriol. 129, 1010-1019), was localized via electron microscope histochemistry in cells cultured under conditions which result in increased quantities of this activity. This soluble alkaline phosphatase was stabilized with 20% glycerol and purified to homogeneity as determined by sodium dodecyl sulfate(SDS)-polyacrylamide gel electrophoresis. The purified enzyme is soluble in dilute buffer. This soluble alkaline phosphatase has been characterized and compared to the membrane-associated alkaline phosphatase from this organism.

Alkaline Phosphatase↗