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M Sellin

Publications and source records attributed to M Sellin.

29 records · Page 2Linked to original sources
PubMed1992

Multiple ciguatoxins in the flesh of fish.

Most cases of ciguatera (fish poisoning) result from consumption of the flesh of fishes contaminated with ciguatoxin(s); however, the relatively low toxicity of ciguateric fish flesh has hindered attempts to identify these ciguatoxin(s). Utilising high performance liquid chromatography, mass spectroscopy and mouse bioassay signs we have determined that ciguatoxin-1 (MH+ m/z = 1112), ciguatoxin-2 and ciguatoxin-3 are the major ciguatoxins present in the flesh of ciguateric fish. Ciguatoxin-1, -2 and -3 were present in yields of 0.19, 0.09 and 0.02 microgram/kg flesh, respectively, in Scomberomorus commersoni; 0.08, 0.09 and 0.07 microgram/kg flesh, respectively, in Plectropomus spp. and; 0.67, 0.61 and 0.06 microgram/kg flesh, respectively, in Pomadasys maculatus. Two minor toxins, which may be further oxidised analogues of ciguatoxin-1 and ciguatoxin-2, were also identified. The presence of multiple ciguatoxins in fish flesh has important consequences for the detection of ciguateric fish and may be a contributing factor to the observed variability in the symptoms of ciguatera.

Animals↗
PubMed1992

Endocarditis caused by a group B Streptococcus strain, type III, in a nonencapsulated phase.

A nontypeable blood isolate of group B streptococci (GBS) from a patient with endocarditis is suggested to be the nonencapsulated phase of a GBS strain, type III. From the original high-density isolate, a low-density, encapsulated phase was selected by Percoll gradient centrifugation. This phenomenon should be considered before a GBS strain is classified as truly nontypeable.

Adult↗
PubMed1991

Purification and characterization of ciguatoxins from moray eel (Lycodontis javanicus, Muraenidae).

Viscera (48.3 kg) from moray eels (Lycodontis javanicus) collected in a ciguatera endemic area were extracted and the ciguatoxins characterized. Three major ciguatoxins, CTX-1, CTX-2 and CTX-3, were isolated and purified to homogeneity on reverse phase high performance liquid chromatography. Several minor toxins were also detected. CTX-1 (490 micrograms) was comparable by both 1H nuclear magnetic resonance (1H NMR) and mass spectroscopy (MH+ m/z = 1111) to ciguatoxin isolated previously from moray eels. CTX-2 (280 micrograms) and CTX-3 (100 micrograms) were less polar ciguatoxins not previously characterized. CTX-2 and CTX-3 differed from CTX-1 by 16 mass units, suggesting that they were less oxygenated analogues. 1H NMR revealed that the hydroxyl at C54 in CTX-1 was absent in CTX-2 and CTX-3. An additional change in the chemistry of CTX-2 compared to CTX-1 and CTX-3 was also suggested on the basis of 1H NMR, indicating that CTX-2 may arise from a different precursor to CTX-1. CTX-3 is likely to be an intermediate in the oxidation of a gambiertoxin (sodium channel toxins from Gambierdiscus toxicus) to CTX-1. The i.p. LD50 values for CTX-1, CTX-2 and CTX-3 were 0.25, 2.3 and 0.9 micrograms/kg, respectively. The signs induced in mice by the ciguatoxins were similar, except that CTX-2 and CTX-3 induced hind-limb paralysis that was absent with CTX-1. Each ciguatoxin was potent orally. CTX-1, CTX-2 and CTX-3 competitively inhibited the binding of [3H]brevetoxin-3 to voltage-dependent sodium channels with relative potencies qualitatively (but not quantitatively) comparable to mouse lethality. This study reveals that the relatively small chemical differences between CTX-1, CTX-2 and CTX-3 give rise to significant structure-activity and pharmacokinetic differences.

Animals↗
PubMed1991

[Autologous transfusion in heart surgery (apropos of 74 patients)].

The present study uses three techniques of autotransfusion in heart surgery under ECC: peroperative and post-ECC transfusion of blood removed after induction of anaesthesia (group I: 25 patients); postoperative transfusion of extravasated thoracic blood (group II: 24 patients) and a combination of the two (group III: 25 patients). Postoperative bleeding was comparable in all groups; A subset likely to haemorrhage made up of patients who had lost more than one litre of blood was isolated and demonstrated a reduction in the number of homologous red cell concentrates needed for the autotransfused population in comparison with the controls (2.4 +/- 2.6 vs 5.7 +/- 3.5 red cell concentrates, p less than 0.05) and was particularly marked in Group II patients who received 1.9 +/- 2.2 homologous red cell concentrates. None of the techniques caused any side-effects. Combination of the two autotransfusion techniques in heart surgery does not secure any additional advantages compared with postoperative autotransfusion alone.

Blood Transfusion, Autologous↗
PubMed1990

Demonstration and characterization of buoyant-density subpopulations of group B Streptococcus type III.

Group B Streptococcus (GBS) type III (18 strains) was investigated for the presence of buoyant-density subpopulations; 10 strains originated from invasive isolates causing early-onset septicemia, and 8 were colonizing isolates from pregnant women. By repeated processing in hypotonic density gradients of Percoll, high- (HD) and low-density (LD) subpopulations were recovered from all strains. Synthesis of type-specific polysaccharide (TPS) was increased in the invasive isolates and their respective LD variants compared with the colonizing strains and their LD subpopulations. Production of capsular TPS correlated directly with synthesis of soluble TPS; there was an inverse exponential relationship between soluble TPS production and buoyant density. LD variants were more resistant to phagocytic killing by human polymorphonuclear leukocytes (PMNL) than were the original strains and HD variants. In a luminol-enhanced chemoluminescence assay, LD variants elicited a weak, slow response. In contrast, the HD subpopulations evoked a prompt, strong respiratory burst in the PMNL.

Centrifugation, Density Gradient↗
PubMed1975

Micrococcal urinary-tract infections in young women.

In a prospective study in young women, novobiocin-resistant subgroup-3 micrococci were the second commonest cause, after Escherichia coli; of acute urinary infections. Proteus mirabilis was the only other causative organism. Symptoms, pyuria, or possible aetiological factors were the same in micrococcal and coliform infections. The infecting micrococcus "biotype" was only rarely found among the normal flora of the genitourinary tract of young women, though other micrococci and staphylococci were commonly present. Evidently, the infecting micrococci are selectively pathogenic in the urinary tract. Micrococcal infections, like coliform infections; commonly followed sexual intercourse, but there was no evidence that the micrococci were sexually transmitted. The infecting biotype was rarely found in the male urethra or prepuce.

Drug Resistance, Microbial↗
PubMedDate not supplied

[Heart transplantation. Clinical study and results apropos of a consecutive series of 100 first grafts].

OBJECTIVES: Global results of entire series of heart transplantations are essential to better evaluate survival rates. We therefore report the results of our first 100 transplantations. METHODS: Orthotopic heart transplantation was performed in 82 men and 18 women (age 50.5 +/- 11.4; range 9-65). Sixteen were over 60. Primitive cardiomyopathies (n = 51) and coronary artery disease (n = 44) were the most frequent underlying diseases. Secondary morbidity was evaluated according to the international classification on the basis of pathological examination of endomyocardial biopsies. RESULTS: Immediate post-operative survival rate was 89 percent: there was 1 peroperative death, 7 deaths due to persistent pulmonary hypertension and 4 due to irreversible left ventricular failure. Eight deaths occurred during the 2nd and 3rd postoperative months for an overall early survival rate of 81 percent. After a mean follow-up of 2.4 years (maximum 6.16 yr), the actuarial survival rate at 5 years was 58 percent. Among the 470 biopsies performed, rejection was classified weak or null in 326, moderate in 125 and severe in 19. Pulmonary artery resistance, immunosuppression and, later, the risk of coronary artery disease and intrinsic graft changes were the three major problems encountered in this series. CONCLUSIONS: Despite its limits, heart transplantation remains an effective therapeutic option, particularly for young patients in good general health.

Adolescent↗
PubMedDate not supplied

[Mediastinitis after cardiac surgery. A 10-year evaluation (1985-1995)].

UNLABELLED: From June 1985 to May 1995, 9,814 patients were operated for a cardiac procedure with cardiopulmonary by-pass. Mean age was 61,3 years. The most frequent procedure was coronary surgery (45%), followed by valvular surgery (34%) then combined surgery (11%) and other surgery (4%). 66 cases of mediastinitis were observed: 38 from June 1985 to May 1990 (first group), 28 from June 1990 to May 1995 (second group). The changes between the two groups was antibiotic prophylaxis using Cefuroxime in the first group and Cefamandole in the second and also an impairment of general status of the patients in the second group. Staphylococcus remains the most frequent organism in both groups and for Gram negative bacteria was less frequent in the second group. Several risks factors mediastinitis were identified (males, emergency, diabetes mellitus, obesity, redo, patient of first group, duration of Cardiopulmonary by pass for 100 minutes, mechanical ventilation greater than 48 hours) and the most important factor was the need for mechanical ventilation for more than 48 hours. The mortality rate was 39.4% (26 patients). Identified risk factors of mortality were age over 65 years, females, poor constitution, and cardio/thoracic ratio > 0.55. CONCLUSION: Mediastinitis after cardiac surgery remains a serious complication. In this series we observed a decrease of mediastinitis rates, especially in the second group (p < 0.001). In high risk patients, specific preoperative methods of patient care may be able to prevent such complications. When mediastinitis appears, and when debridement is necessary, a cover procedure seems necessary in elderly or poor constitution patients.

Adolescent↗