Carcinogens and cancers in freshwater fishes.

Epizootics of neoplasms in freshwater fish species are considered in relation to circumstantial and experimental evidence that suggest that some epizootics of neoplasia of hepatocellular, cholangiocellular, epidermal, and oral epithelial origin may be causally related to contaminant exposure. Although there is concern for the safety of consuming fish affected with neoplasms, this concern may be misdirected as direct transmission of cancer by ingesting cancerous tissue would seem unlikely. Of greater concern is the matter of toxic and cancer-causing chemicals present in edible fish that exhibit neoplasia as a symptom of past exposure via residence in a polluted waterway. There is ample evidence to suggest that contaminant chemicals ingested via contaminated Great Lakes fish may already be affecting both human and ecosystem health, but these effects are subtle and may require new approaches to the study of the affected systems.

Decline in liver neoplasms in wild brown bullhead catfish after coking plant closes and environmental PAHs plummet.

Polycyclic aromatic hydrocarbons (PAHs) in both sediment and brown bullhead catfish tissues from the Black River in Lorain County, Ohio, declined by 65% and 93%, respectively, between 1980 and 1982. Sediment PAHs declined an additional 99% by 1987, coincident with the closure of a coking facility in 1983. Contemporaneously, liver cancer in 3- to 4-year-old brown bullheads declined to about one-quarter the 1982 frequency (10% versus 39%) by 1987, while the percentage of livers without any proliferative lesions doubled (42% versus 20%). These changes were significant within age group. Our data affirm a cause-and-effect relationship between PAH exposure and liver cancer in wild fish. The data also support the efficacy of natural, unassisted remediation once the source of the pollution is eliminated.

Dissection of the descending thoracic aorta extending into the ascending aorta. A therapeutic challenge.

Proper management of dissections of the descending thoracic aorta with intimal disruption close to the left subclavian artery and retrograde extension of the dissection into the aortic arch or the ascending aorta is controversial, because the standard approach for ascending aortic aneurysms is surgical repair, which is difficult to achieve through a median sternotomy if the predominant aortic lesion is located in its descending part. Sixteen patients with descending thoracic aortic dissection, intimal disruption close to the subclavian artery, and extension of the dissection into the aortic arch or the ascending aorta are described here: Eleven patients underwent surgical repair including 9 emergency (82%) and 2 elective (18%) procedures. Retrograde aortic dissection included the aortic arch in 11 of 11 patients (100%) and the ascending aorta in 7 of 11 (63%). Pericardial effusion was present in 1 of 11 patients (9%) and mild aortic regurgitation was found in 1 of 11 (9%). Repair of the ascending aorta and arch with transaortic closure of the entrance tear in the descending thoracic aorta was performed in 4 of 11 patients (36%) via a median sternotomy. In 6 of 11 patients (55%) a lateral thoracotomy was used for repair of the descending thoracic aorta and closure of the entrance tear. Hospital mortality occurred in 1 of 11 patients (9%) and there was 1 late death. Paraplegia occurred in 1 of 11 patients (9%). Five patients with descending thoracic aortic dissection, intimal disruption close to the subclavian artery, and extension into the ascending aorta but without ascending aortic aneurysm (diameter 4.2 +/- 0.2 cm), pericardial effusion, or aortic incompetence were treated medically without early mortality. These results are compared with those achieved in 120 patients operated on during the same period for type A (89/120) and type B (31/120) aortic dissections. Considering the technical difficulties of simultaneous repair of dissections of the ascending and the descending thoracic aorta, we recommend that descending thoracic aortic dissection extending into the arch or the ascending aorta be managed in accordance with the site of the predominant lesion. Replacement of the arch with a varying portion of ascending aorta via a median sternotomy is recommended in patients with enlarged aortic diameter, pericardial effusion, and/or aortic insufficiency. Predominantly distal dissections with dilated descending thoracic aorta and/or distal complications are best approached via a lateral thoracotomy.

Prehospital and hospital coronary care.

This article reviews the current state of services for coronary care. Since the majority of deaths from coronary heart disease occur early and outside the hospital, the importance of the prehospital phase is emphasized. The delay in this period, which is very dangerous for the patient, should be reduced and mobile coronary care units (MCCU's) are one possibility to reduce the rate of sudden coronary death. Different systems of MCCU's are discussed: (1) those based on a hospital coronary care unit, usually accompanied by a nurse and/or a doctor and (2) those integrated into an already existing decentralized emergency system (e.g. fire department) run by paramedics. Although long-term survival of patients resuscitated from ventricular fibrillation is not so good, the results of many of these units are remarkable.

Nosocomial infections in intensive care wards: a multicenter prospective study.

In a three-year prospective investigation, a total of 6,952 patients were investigated prospectively in nine intensive care wards and their rate of nosocomial infections was analysed. The frequency of the nosocomial infections varied between 3% and 27%. The most frequent nosocomial infections were urinary tract infections, sepsis, infections of the skin and of the subcutaneous tissue, pneumonia and wound infections. The most frequent causes of sepsis were ventilation pneumonia, venous catheters, wound infections and urinary tract infections. The pathogen spectrum was analysed. By specific control of infection with employment of an infection control nurse, the frequency of nosocomial infections on intensive care wards was lowered from 17.2% to 14.3% within one year in one of the hospitals.

Epizootics of cancer in fish associated with genotoxins in sediment and water.

Neoplasm epizootics in fish from a wide variety of freshwater, marine, and estuarine locations have been associated with genotoxins in sediment or water. The majority of cases have involved benthic or bottom feeding fish living in habitats with sediment contaminated by PAHs. The most common lesions involved in such epizootics include liver neoplasms, both biliary and hepatic, and skin neoplasms. Laboratory research has demonstrated the ability of fish to metabolize carcinogenic PAHs such as B(a)P into the ultimate carcinogen with the resulting formation of DNA adducts. Fish dosed with B(a)P or sediment extracts containing carcinogenic PAHs have developed skin and liver neoplasms. In the Black River, OH, neoplasm prevalence in wild brown bullhead has reflected PAH exposure as the latter has changed due to coke plant closures and remedial dredging activity. The weight of evidence supports a cause-and-effect relationship between exposure to genotoxins in sediment and water and neoplasm epizootics in wild fish populations.

Relationship between liver tumors and age in brown bullhead populations from two Lake Erie tributaries.

We compared liver tumor frequencies, and age and length characteristics of brown bullheads (Ictalurus nebulosus) of greater than 250 mm total length from two Lake Erie tributaries. Bullheads taken from Old Woman Creek (n = 144) had no grossly observable liver tumors, while those collected in the highly industrialized Black River (n = 532) had a 30% frequency of grossly visible liver tumors during 1981-1982. Liver lesions diagnosed histologically in a randomly collected sample (n = 125) of brown bullheads from the Black River included both biliary and hepatic lesions, with cancerous neoplasms occurring in 38.4% of the fish. Black River bullheads of combined ages 4 and 5 had a significantly (p less than or equal to 0.05) greater prevalence of biliary carcinomas (35.5%) than those of ages 2 and 3 combined (18.4%). Biliary carcinoma was significantly more prevalent than hepatocellular carcinoma in age 4 fish (sexes combined) and in males of ages 3 and 4. The prevalence of hepatocellular carcinoma was significantly higher in females than in males. Age distributions of bullheads differed significantly between the two sites, while length distributions were similar. No brown bullheads of ages 6 or 7 were collected in the Black River, while these age groups composed 18% of the catch in Old Woman Creek. Brown bullheads of age 5 were almost six times more numerous in the Old Woman Creek than in Black River collections. These age and length distributions are consistent with the hypothesis that brown bullheads in the Black River were subjected to an age-selective mortality associated with high prevalences of liver carcinoma.

[Thrombolysis in acute myocardial infarct. An established therapy with open questions]. / Thrombolyse beim akuten Myokardinfarkt. Eine etablierte Therapie mit offenen Fragen.

Intravenous thrombolysis is an established form of therapy within the first 4-6 hours of acute myocardial infarction. In numerous randomized controlled trials it has been shown to be effective in restoring myocardial perfusion, reducing mortality and improving ventricular function. The data so far available do not allow conclusions regarding the best lytic substance. The complication rate is surprisingly low. As adjunctive therapy, aspirin exerts an additive effect and heparin should be given for the first 48 hours. Its exact role is still under investigation. Several ongoing studies are designed to answer the remaining questions: (1.) Which patients with symptoms of more than 6 hours' duration could benefit from thrombolysis? (2.) Should patients with unstable angina be given this treatment? (3.) To minimize delay, it might be beneficial to start thrombolysis in the prehospital phase, but the problems of information and organization need to be solved. (4.) Attempts are being made to further improve thrombolytic and adjunctive therapy.

[Ethical aspects and problems in intensive care medicine]. / Ethische Aspekte und Probleme in der Intensivmedizin.

In the Intensive Care Unit important decisions in critically ill and often incompetent patients have to be made within a short period of time and without all the necessary information. Two main questions arise: 1. How can the autonomy of the patients be respected under these circumstances? 2. Which diagnostic and therapeutic activities are adequate and reasonable in each individual patient? An optimal communication between the people involved helps to find the best answers.

[Additional pacemaker indications]. / Erweiterte Schrittmacher-Indikationen

In addition to the widely accepted criteria for the implantation of a permanent pacemaker (bradyarrhythmias combined with syncope, cardiac decompensation, angina pectoris etc.) ther are borderline situations where the decision for a pacemaker is less easy: 1) marked bradycardia with only minor symptoms, 2) syncope without appropriate electrocardiographic abnormality, 3) bifascicular blocks, 4) tachyarrhythmias refractory to medical therapy. In connection with these situations, 3 syndromes are discussed with particular reference to the indication for pacemaker: A) hyperactive carotid sinus reflex syndrome, B) sick sinus syndrome, C) fascicular block. A pacemaker is a fairly safe method of therapy (although with some complications) which should not only be used as a last resort (e.g. in severe Adams-Stokes syndrome) but in patients whose condition may improve after a pacemaker implantation or be prevented from getting worse. Patients with pacemakers have a mean survival rate of 80-90% after 1 year and of 50-60% after 5 years.

[Arrhythmias in acute coronary heart disease]. / Rhythmusstörungen bei der akuten koronaren Herzkrankheit.

Almost any arrhythmia can occur as a complication of an acute coronary event. Many of them are frequent, but ventricular arrhythmias are predominant; supraventricular arrhythmias and conduction disturbances are only briefly reviewed in this article. Ventricular arrhythmias are important not only if they occur during the acute phase of a myocardial infarction but also when they are an acute symptom of coronary artery disease in themselves without evidence of myocardial necrosis. This article deals with the pathogenesis of ventricular arrhythmias, the factors influencing arrhythmias, the concept of warning premature beats, and prophylaxis and therapy in hospital as well as in the prehospital phase. In hospitalized patients these arrhythmias usually can be treated without major difficulty, but in the prehospital phase a further reduction of mortality probably could be achieved by suitable measures.

[The importance of hemodynamic monitoring in intensive care]. / Die Bedeutung der hämodynamischen Uberwachung in der Intensivmedizin.

In intensive care medicine it is often difficult to treat patients with impaired circulatory function adequately without hemodynamic monitoring. The indications for this type of monitoring, the prerequisites and the consequences are briefly discussed. Optimal hemodynamic monitoring can be secured if the various available methods (including clinical judgment) are used in appropriate combination.

[Prognosis in complications of acute myocardial infarction requiring artificial respiration]. / Prognose bei Komplikationen des akuten Myokardinfarktes, die eine maschinelle Beatmung nötig machen.

From 1978 to 1981, 818 consecutive patients with acute myocardial infarction were admitted, 112 (13.7%) of whom required artificial ventilation because of complications. Their mean age (62) corresponded to the mean age of all acute myocardial infarction patients (63). 28 (25%) survived the hospitalization and were followed after discharge. 2 were lost to follow-up. After a mean follow-up period of 26 months, 8 patients had died and 18 were still alive, none of them free of symptoms. There was no difference of age, duration of respirator therapy and maximal creatine kinase activity between survivors (group A) and nonsurvivors (group B). In 50% of patients cardiac failure leading to endotracheal intubation was triggered or made worse by arrhythmias. The remaining 50% of patients showed pure pump failure. Again in these two subsets, cardiac failure was significantly less marked in group A than in group B according to the hemodynamic findings. In conclusion, inpatient mortality in patients with acute myocardial infarction requiring artificial ventilation was high (75%) and hemodynamic findings were significantly worse in those not surviving. Patients discharged from the hospital also had a reduced life expectancy (less than 50% after 3 years).

Pathology and tumor development through time in guppies dosed with diethylnitrosamine (DEN).

Within the last decade unusually high frequencies of neoplasms have been reported in feral fish populations from a variety of locations. At many of these locations organic carcinogens have been noted as a potential cause. We sought to identify toxic effects including neoplasia in fish exposed to an organic carcinogen, and to quantify these effects through time. We exposed guppies (Poecilia reticulata) to multiple doses of DEN, an organic carcinogen. Fish were then subsampled and examined for liver histopathology at 2-month intervals over 12 months. Necrotic zones, macrophage centers, bile duct proliferations, enlarged lipid deposits, neoplastic foci, cholangiocarcinomas and hepatoblastomas were quantified by frequency of occurrence and the percentage of liver area involved. DEN toxicity resulted in necrotic zones that peaked in frequency at the first sample period (2 months). Lipid deposits increased, then plateaued in guppies, indicating a more chronic toxic effect. Similarly, macrophage centers increased through the sampling period. Bile duct proliferation appeared to be of two types: a reversible toxic response which peaked at 4 months and then declined and a less frequent irreversible proliferation which continued to develop into cholangiocarcinoma. Neoplastic foci of mixed hepatocytes and cholangiocytes increased in livers of exposed guppies from the second month, developing into hepatoblastomas, which occurred in almost 100% of exposed guppies by the twelfth month. The irreversible bile duct proliferations and the neoplastic foci had cellular densities different from corresponding control tissue and similar to cellular densities of cholangiocarcinomas and hepatoblastomas, respectively.

Pneumocystis carinii pneumonia and mucosal candidiasis in a previously healthy homosexual man.

A fatal case of Pneumocystis carinii pneumonia in a previously healthy homosexual man with no evidence of malignancy is reported. Despite appropriate treatment with high doses of i.v. trimethoprim-sulfamethoxazole, the patient died.

[Cyanide poisoning]. / Cyanid-Intoxikation.

Acute cyanide poisoning is a rare but usually fatal intoxication. Rapid diagnosis and immediate initiation of therapy are important, since a number of effective and potentially life-saving antidotes are available. Pathophysiology, signs, symptoms, course and therapy are discussed, and three personal observations are presented.

[Toxicity and blood concentration of thiocyanate during sodium nitroprusside treatment]. / Toxizität und Konzentration von Thiocyanat im Serum bei der Therapie mit Natrium-Nitroprussid.

In 25 patients receiving sodium nitroprusside (SNP) infusion for hypertension, the influence of SNP on renal function, thiocyanate (SCN) concentration, half-life of SCN and hemolytic actions or methemoglobinemia was measured. Creatinine clearance showed a slight increase while plasma creatinine was unchanged. There was no definite relationship between creatinine clearance and SCN clearance. For the individual patient there was no relationship between the SCN concentration at a constant dose of SNP and the degree of renal function. Independently of the grade of renal insufficiency, toxic concentrations of SCN were never seen if less than 100 gamma/min/SNP were infused for less than 5 days ( = less than 720 mg total dose). There was a linear relationship between half-life of SCN and the degree of renal function. Signs of hemolytic action could not be demonstrated. There was no methemoglobinemia. Although SCN concentration in relation to dose of SNP and renal function cannot be predicted, it is proposed that plasma SCN be checked only in patients receiving more than 100 gamma/min for more than 5 days.