Two Lines of Walker Carcinoma 256: Their Peculiarities and Different Interactions with the Host

Two sublines of Walker 256 carcinoma have been characterized for their ability to metastasize and to induce cachexia. The invasive, metastasizing line A induced terminal anorexia in rats with a mean survival time of 27 ± 1.5 days. The non-invasive line B induced early anorexia and cachexia with a mean survival time of only 15 + 1 days. At death, the line B tumor was still smaller than the line A one, and no metastases were detectable. These two sublines are discussed as a composite model for studying anorexia and cachexia together with invasion and metastasis.

Effect of the introduction of a lumbar-puncture sticker and teaching manikin on junior staff documentation and performance of paediatric lumbar punctures

BACKGROUND

Performing a lumbar puncture in an unwell child can cause anxiety in both the parent and the junior doctor. There is increasing evidence of post-lumbar-puncture complications in this age group.

AIMS

To improve the documentation, consent for and technical performance of paediatric lumbar punctures to 100% of the required standard within 3 months.

SETTING

The paediatric emergency department of a the Royal North Shore Hospital (University of Sydney, Sydney, Australia).

PARTICIPANTS

Paediatric emergency staff, including residents, registrars and consultants.

METHODS

Medical records of 40 consecutive children who had undergone a lumbar puncture in the 6 months before the introduction of the lumbar-puncture proforma were reviewed. After introduction of the proforma, the records of 25 consecutive patients were reviewed to assess changes in the outcome measures. Before introduction of the proforma, junior medical staff were instructed in the procedure using specialised lumbar puncture manikins (Baby Stap; Laerdel, USA).

RESULTS

Before introduction of the proforma, the median number of documented indicators was 4, out of a maximum of 12. There was almost no documentation of parental consent, patient complications and analgesia. Introduction of the proforma resulted in a highly marked increase to a median of 12 documented indicators per patient (p<0.01, 95% confidence interval 6 to 8).

CONCLUSIONS

The introduction of a lumbar-puncture proforma and formal teaching sessions using a paediatric manikin led to a marked improvement in the documentation of paediatric lumbar-punctures. Lumbar-punctures can be performed only by accredited medical officers who have achieved competency on the lumbar-puncture teaching manikin.

PNU-159548, a novel cytotoxic antitumor agent with a low cardiotoxic potential

PURPOSE

PNU-159548 (4-demethoxy-3'-deamino-3'aziridinyl-4'-methylsulphonyl-daunorubicin), a derivative of the anticancer idarubicin, has a broad spectrum of antitumoral activity in vitro and in vivo attributable to its DNA intercalating and alkylating properties. The present study was conducted to determine the cardiotoxic activity of PNU-159548 relative to doxorubicin in a chronic rat model sensitive to anthracycline-induced cardiomyopathy.

METHODS

Young adult male rats were allocated to the following treatment groups: group 1, PNU-159548 vehicle control (colloidal dispersion); group 2, doxorubicin control (saline); groups 3, 4, 5, 6, and 7, PNU-159548 at 0.12, 0.25, 0.50, 0.75, and 1.0 mg/kg, respectively; and group 8, 1.0 mg/kg doxorubicin. Treatments were administered intravenously once weekly for 4 weeks (first sacrifice time) or for 7 weeks (rats killed at weeks 8, 12, 22, 27, or 35). Body weights, organ weights, serum chemistry, hematology, serum troponin-T, and cardiac histopathology were followed throughout the study.

RESULTS

Doxorubicin caused irreversible cardiomyopathy evident at week 4 in some rats and progressing in severity in all rats by week 8. There were also marked myelotoxicity, increased liver and kidney weights, testicular atrophy, and about 20% mortality by week 27 in doxorubicin-treated rats. The deaths were attributed to cardiomyopathy and/or nephropathy. PNU-159548 caused a dose-dependent myelotoxicity, with the dose of 0.5 mg/kg per week being equimyelotoxic to 1.0 mg/kg per week doxorubicin. PNU-159548 also caused an increase in liver weight that was reversible and a non-reversible testicular atrophy but, unlike doxorubicin, had no effect on kidney weight. At equimyelotoxic doses, the cardiotoxicity caused by PNU-159548, expressed as the mean total score, was less than one-twentieth of that induced by doxorubicin, and much less than that predicted on the basis of its content of idarubicin, which is in turn markedly less cardiotoxic than doxorubicin.

CONCLUSIONS

The novel cytotoxic antitumor derivative, PNU-159548, is significantly less cardiotoxic than doxorubicin at equimyelosuppressive doses. The combination of intercalating and alkylating activities within the same molecule without the cardiotoxic side effects of anthracyclines makes PNU-159548 an excellent candidate for clinical development in oncology.

Pharmacological and toxicological aspects of 4-demethoxy-3'-deamino-3'-aziridinyl-4'-methylsulphonyl-daunorubicin (PNU-159548): a novel antineoplastic agent

4-demethoxy-3'-deamino-3'-aziridinyl-4'-methylsulphonyl-daunorubicin (PNU-159548) belongs to a novel class of antitumor compounds (termed alkycyclines) and is currently undergoing Phase II clinical trial. In the present study, we investigated the in vitro and in vivo antitumor activity, the pharmacokinetics, and the toxicological profile of this compound. PNU-159548 showed good cytotoxic activity in murine and human cancer cells growing in vitro, with an average concentration for 50% growth inhibition of 15.8 ng/ml. The drug showed strong antitumor efficacy in vivo after i.v. and p.o. administration against rapidly proliferating murine leukemias and slowly growing transplantable human xenografts. At non-toxic doses, PNU-159548 produced complete regression and cures in ovarian, breast, and human small cell lung carcinomas. Fourteen of 16 models studied, including colon, pancreatic, gastric, and renal carcinomas, astrocytoma and melanoma, were found to be sensitive to PNU-159548. In addition, PNU-159548 was effective against intracranially implanted tumors. Toxicological studies revealed myelosuppression as the main toxicity in both mice and dogs. The maximum tolerated doses, after a single administration, were 2.5 mg/kg of body weight in mice, 1.6 mg/kg in rats, and 0.3 mg/kg in dogs. In the cyclic studies, the maximum tolerated doses were 0.18 mg/kg/day (cumulative dose/cycle: 0.54 mg/kg) in rats and 0.05 mg/kg/day (cumulative dose/cycle: 0.15 mg/kg) in dogs. PNU-159548 showed minimal cardiotoxicity, when compared with doxorubicin in the chronic rat model at a dose level inducing similar myelotoxicity. Animal pharmacokinetics, carried out in mice, rats, and dogs, was characterized by high volumes of distribution, plasma clearance of the same order of the hepatic blood flow, and short terminal half-life. These findings support the conclusion that PNU-159548 is an excellent candidate for clinical trials in the treatment of cancer.

An evaluation of the results of two non-surgical methods in the treatment of fractures of the odontoid process

The authors illustrate the results of a series of 47 fractures of the odontoid process all treated according to two non-surgical methods, among the most diffused and accepted: Minerva plaster and halo-plaster. The various elements used to classify odontoid fractures are examined, as is their importance for prognosis. The conclusions refer to two essential points: 1) fractures with a higher risk of nonunion are Anderson type II, with posterior shifting, in elderly patients; 2) reduction and immobilization with a halo-plaster may be considered the first choice of a method for most of these fractures, in consideration of the limited risk of nonunion involved.

Cardioprotection by dexrazoxane in rats treated with doxorubicin and paclitaxel

PURPOSE

Results of several clinical studies suggest that the combination of doxorubicin (DOX) and paclitaxel (PTX) is highly active against solid tumors. Both drugs are known to cause adverse cardiac effects, cardiomyopathy in the case of DOX and acute changes in cardiac rhythm in the case of PTX. It has been suggested that the addition of dexrazoxane (DZR) to this regimen may reduce the risk of cardiotoxicity. A model of chronic cardiomyopathy in the rat was used to determine whether DZR was tolerated and cardioprotective in a DOX + PTX combination.

METHODS

Male rats were treated once weekly for 7 weeks with one of the following vehicle and/or drug sequences: Group A, M/6 sodium lactate/saline/Cremophor EL (CEL); Group B, lactate/DOX/CEL; Group C, DZR/DOX/CEL; Group D, lactate/DOX/PTX; and Group E, DZR/DOX/PTX. DZR and DOX or their respective vehicles were given i.v. whilst PTX or CEL were given i.p. DZR, DOX and PTX were administered at 16 mg/kg, 0.8 mg/kg and 2.4 mg/kg, respectively, doses which caused minimal noncardiac toxicities. The hearts were examined histologically 5 weeks following the last treatment.

RESULTS

There were no deaths and no signs of overt toxicity during the 12 weeks of study. There was a significant decrease (P < 0.01) in white blood cell count in rats treated with DZR + DOX, DOX + PTX or DZR + DOX + PTX but not in those given DOX alone. Liver and kidney weights were increased in rats given DOX (P < 0.05) but not in those given DZR + DOX. PTX had no effect on the DOX-induced liver and kidney changes and did not interfere with the protective effect of DZR on the kidney. The severity and extent of cardiomyopathy expressed as the mean total score (MTS) for each treatment group, was similar for DOX and DOX + PTX (4.6 and 4.2, respectively). DZR provided significant cardioprotection (P < 0.01) when added to either DOX (MTS 2.0) or to DOX + PTX (MTS 2.1).

CONCLUSIONS

The results suggest that PTX does not exacerbate the chronic cardiomyopathy caused by DOX and when added to the DOX + PTX combination, DZR retains its protective activity against DOX-induced cardiotoxicity without increasing noncardiac toxicity.

Influence of mutations associated with familial prion-related encephalopathies on biological activity of prion protein peptides

In transmissible spongiform encephalopathies (TSEs), an altered form of prion protein (PrP), PrPres, aggregates in amyloid fibrils and accumulates in the brain. Several point mutations of the PrP gene have been associated with the TSEs, so, to investigate how the mutations affect the biological activity of PrP, we analyzed the biological effects and chemicophysical characteristics of the peptide homologous to the wild-type and mutated sequence of PrP fragments. The mutation P102L altered the biological activity of PrP 89-106, which became neurotoxic without changing its fibrillogenic capacity. The mutation (D178N) in the PrP 169-185 strongly increased the neurotoxic activity of the native sequence. In this case, there was also a clear alteration of the structural conformation. None of the other mutations considered, including A117V, seemed to influence the biological activities of the respective peptides. These data identify new neurotoxic fragments of PrP in the mutated form and elucidate their genetic influence on the pathogenesis of TSEs.

Protection against doxorubicin-induced cardiotoxicity in weanling rats by dexrazoxane

PURPOSE

Dexrazoxane (DZR) protects against anthracycline-induced cardiotoxicity in several laboratory animal species and in patients with breast cancer. Encouraging results have also been obtained in a limited number of pediatric oncology patients. We conducted studies to determine the safety and cardioprotective activity of DZR in the doxorubicin (DOX)-treated weanling rat simulating the rapidly growing immature child.

METHODS

Male weanling rats and young adult rats, 20 days old and 7 weeks old, respectively, were given 1 mg/kg DOX i.v., either alone or with 20 mg/kg DZR, once weekly for 7 weeks. Rats were sacrificed at weeks 8, 12 or 26 following blood collection for hematology and serum chemistry. Hearts were weighed and examined histologically.

RESULTS

DOX, either alone or with DZR, inhibited growth, and body weight remained below that of controls throughout the 26 weeks of study. There were no biologically significant hematologic changes in either the DOX- or DZR + DOX-treated young rats. DOX caused a slight increase in liver and kidney weights relative to body weight and a slight increase in serum cholesterol and triglycerides in the young rats. These effects were ameliorated or delayed by DZR. DOX, either alone or with DZR, caused a marked atrophy of the testes in the young rats which had recovered by week 26. In the mature rats, DOX caused a significant decrease in the WBC 1 week after the last treatment, and the WBC was significantly lower in the rats given DZR + DOX compared to those given DOX alone. There were marked increases in liver and kidney weight, serum cholesterol and triglycerides in the mature rats given DOX alone but not in those given DZR + DOX. There was also a marked testicular atrophy in the mature rats given either DOX or DZR + DOX but, unlike that observed in the young rats, this had not returned to normal by week 26. DOX-induced cardiotoxicity was less severe in the younger rats than in the mature rats but in both age groups, the lesion progressed rapidly until week 12, 5 weeks after the last dose, and remained relatively stable or progressed slightly thereafter. DZR provided significant cardioprotection in both age groups at all time points examined. Moreover, in both age groups, the severity of the cardiomyopathy in the DZR-treated rats was somewhat less at week 26 than it was at week 12.

CONCLUSIONS

The results indicate that the pharmacologic effects of DZR, including its ability to protect against cardiotoxicity, are similar in immature and adult male animals treated with DOX.

Amidation of beta-amyloid peptide strongly reduced the amyloidogenic activity without alteration of the neurotoxicity

Beta-amyloid accumulates in cerebral deposits in Alzheimer's disease, so to test the correlation between the neurotoxic and fibrillogenic capacity of beta-amyloid, we synthesized a peptide homologous to fragment 25-35 of beta-amyloid (beta25-35) and amidated at the C-terminus (beta25-35-NH2). As the amidation strongly reduced the amyloidogenic capacity of beta25-35, we compared its neurotoxic activity in the amidated (beta25-35-NH2) and nonamidated forms. The viability of primary cultures from fetal rat hippocampus was reduced in a dose-related manner (10-100 microM) similarly by beta25-35 and beta25-35-NH2, whereas a scrambled peptide, amidated or nonamidated, did not alter the neuronal viability. The neurotoxic activity of beta25-35-NH2 is mediated by apoptosis as demonstrated by morphological and biochemical investigations. Electron microscopy examination of culture media with beta25-35 or beta25-35-NH2 incubated with neuronal cells for 7 days confirmed the high level of fibrillogenic activity of beta25-35 and the almost total absence of fibrils in the solution with beta25-35-NH2. Furthermore, staining with thioflavine S was used to identify amyloid fibrils, and only the cultures exposed to beta25-35 exhibited intense staining associated with neuronal membranes. These data indicate that the neurotoxic activity of the beta-amyloid fragment is independent of the aggregated state of the peptide.

Dose-response relationship of dexrazoxane for prevention of doxorubicin-induced cardiotoxicity in mice, rats, and dogs

Dexrazoxane [(DZR), ADR 529, ICRF-187] ameliorates doxorubicin (DOX)-induced cardiotoxicity in animals, and is recommended as a cardioprotectant in patients receiving cumulative doses of DOX above 300 mg/m2. A DZR:DOX dose ratio of 10:1 is recommended based on studies in patients receiving 50 mg/m2. Since DOX may be used at much higher doses in certain clinical settings, we evaluated the ability of DZR to protect against cardiomyopathy in animals given bolus doses of DOX at varying dose levels. The severity and extent of the cardiomyopathy were evaluated histologically and expressed as the mean total score (MTS). Mice were given 10 doses of DOX (2 or 4 mg/kg) over a 7-week period. Without DZR, the MTS 4 weeks after the last treatment was 3.7 with 4 mg/kg DOX and 1.3 with 2 mg/kg DOX. DZR at 5:1, 10:1, and 20:1 dose ratios caused a dose-dependent decrease in the MTS but was less efficacious with the higher, more cardiotoxic dose of DOX. Rats were given DOX at 0.2, 0.4, and 0.8 mg/kg with a 20:1 ratio of DZR weekly for 13 weeks. Cardiomyopathy was most severe with the highest dose of DOX in the absence of DZR, especially in males, and progressed during the 6 weeks following the last treatment. DZR reduced the MTS in both sexes but in the males given the highest dose of DOX, there was still a significant amount of cardiac damage compared to vehicle-treated controls. Dogs were given 0.1, 0.3, and 0.8 mg/kg DOX with 20:1 DZR for 13 weeks. DZR reduced the MTS significantly (P < 0.05) in males and females but cardiac lesions were still present in each of the DZR-treated dogs. The results indicate that although DZR is highly effective in attenuating the cardiomyopathy caused by DOX, dose ratios of DZR:DOX capable of providing total or nearly complete cardioprotection at low doses of DOX are less efficacious at higher doses of DOX. One possible explanation for this effect is the marked pharmacokinetic difference between DZR and DOX, with DZR undergoing a much more rapid rate of elimination from the body compared to DOX. These findings point to the need for further studies to optimize the dose scheduling of DZR before using it clinically with bolus doses of DOX above those currently recommended.

Long-lasting effect of dexrazoxane against anthracycline cardiotoxicity in rats

The long-lasting protective effect of dexrazoxane (ADR-529) against doxorubicin- and epirubicin-induced cardiotoxicity was evaluated in the multiple-dose 35-wk rat model. Groups of 36 male Sprague-Dawley rats were given ADR-529 30 min before administration of cardiotoxic doses of doxorubicin (1 mg/kg/wk) or epirubicin (1.13 mg/kg/wk). The compounds were intravenously injected once weekly for 7 consecutive wk at ADR-529; anthracycline ratios ranging from 5:1 to 20:1. These ratios covered the entire chemotherapeutic range in humans and allowed studying the chronic progressive cardiomyopathy in our rat model. Animals were observed for up to 35 wk to follow the time course of the well-characterized cardiomyopathy, which was evaluated through the well-established qualitative/quantitative morphological grading. It was clearly demonstrated in this rat model that ADR-529, at the ratios administered, provided ample cardioprotection for a duration of 35 wk, which corresponds to 25 yr of equivalent human time.

Evaluation of 4'-iodo-4'-deoxydoxorubicin-induced cardiotoxicity in two experimental rat models

In the present study, 1 single-dose and 1 multiple-dose models were applied in studying 4'-iodo-4'-deoxydoxorubicin (I-DX) cardiotoxicity. Anthracycline cardiotoxicity has been reproduced in several animals including mice, rats, hamsters, rabbits, dogs, and monkeys. Of these species the rat can be considered the most suitable species for the study of anthracycline-induced cardiomyopathy. The cardiotoxicity induced by I-DX in male Sprague-Dawley rats was compared to that of doxorubicin (DX), used as standard positive control. Groups of 36-42 rats were observed for up to 35 wk to follow the progression of the lesions. Cardiomyopathy was evaluated through well-established qualitative/quantitative morphological grading. The new DX derivative proved to be clearly less cardiotoxic than DX with both treatment schedules. Although both models can be considered useful for evaluating and comparing the cardiotoxicity of new anthracycline derivatives and mimicking the transvenous endomyocardial biopsies in humans, the chronic test seems to be more suitable for compounds like I-DX, which possess a low cardiotoxic potential and which could go undetected in the single-dose test.

The histopathology of kidney changes in rats and monkeys following intravenous administration of massive doses of FCE 26184, human basic fibroblast growth factor

Intravenous administration of human basic fibroblast growth factor up to 100 micrograms/kg/day to Sprague-Dawley rats caused changes in the kidneys that included enlargement, vacuolation, and karyomegaly of podocytes in glomeruli, dilatation and cast formation in tubules, thickening of the media in the lobular arteries, and hyperplasia of the epithelium of the papilla and collecting ducts. In cynomolgus monkeys there was hyperplasia of the parietal epithelium of Bowman's capsule in the glomeruli, tubular dilatation, and minimal arteriopathy. These changes were only seen at 100 micrograms/kg/day. The development and eventual recovery over time were investigated in a sequence of sacrifices. In monkeys the first changes were seen after 7 days of treatment, but in rats only after 16 days. In both species the changes had partially resolved after 30 days of recovery and were considered to return to normal after 60 days without treatment. The morphological changes were accompanied by functional alterations that included proteinuria and raised blood urea. Changes that occurred in other tissues including bone, red blood cells, adrenals, ovaries, liver, gall bladder, spleen, mesenteric lymph nodes, thymus, aorta, salivary glands, and injection site are not described in this paper.

Multinucleated hepatocytes induced by rifabutin in rats

Rifabutin is an antibiotic of the rifamycin class, which is particularly active against mycobacteria, including those that occur in AIDS patients. Because clinical use will include long-term therapy, an extensive battery of long-term toxicity studies was carried out by the oral route, including carcinogenicity studies. An interesting feature was the occurrence of multinucleated hepatocytes (MNHs) in the rat. In some instances, as many as 25 nuclei occurred in a single cell. Light microscopy revealed a large hepatocyte with normal eosinophilic staining. The multiple nuclei stained like those present in the surrounding normal cells. Electron microscopy showed no abnormalities of the nuclei and no cell membranes within the cytoplasm. The customary organelles were present. MNHs were dose- and sex-related, starting from 10 mg/kg/day and being more evident in males. They began to appear after 5 wk of treatment and persisted over long periods of recovery (12 mo), without showing any tendency for cell proliferation. The life-span of MNHs was similar to that of normal hepatocytes. MNHs were present in the carcinogenicity study, but there was no increase in liver tumors. MNHs did not occur in mice or monkeys treated with rifabutin, nor did they occur in response to treatment with rifampin. The effect appears to be specific to the rat.

Characterization of the toxicity of distamycin derivatives on cancer cell lines and rat heart

The cytotoxicity and cardiotoxicity of benzoyl mustard (FCE 24517) and epoxamido (FCE 24561) synthetic derivatives of distamycin A were reported in the present study. The 50% inhibiting concentration (IC50) of colony formation of FCE 24517 on human SNB-19 glioblastoma, A2780 ovarian cancer and DU 145 prostate cancer was at least three times lower than that of FCE 24561; on the same cell lines the IC50 of DXR was up to 14 and 240 times higher than that of FCE 24561 and FCE 24517, respectively. Isolated rat hearts perfused with concentrations of both derivatives equivalent to their respective IC50 values did not show any significant change in ECG parameters, contractility and coronary flow. Compared to control hearts, FCE 24517 10(-6) M induced a significant increase in PR interval, reduction in + dF/dtmax, heart rate and coronary flow, while FCE 24561 10(-6) M produced a modest but significant increase in S alpha T segment and decrease in + dF/dtmax. Rats treated with FCE 24561 3, 6 or 12 mg/kg, intravenously (i.v.), once weekly for 3 weeks had a modest increase in S alpha T segment and QRS complex duration, while a slight alteration of S alpha T segment and QRS complex duration were observed in rats given FCE 24517 1 or 2 mg/kg i.v. once weekly for 3 weeks. No cardiac histologic alterations were found in hearts from rats receiving FCE 24517 or FCE 24561. For comparison, the cardiotoxicity of doxorubicin (DXR) was evaluated in the same experimental models; perfusion of hearts with DXR 10(-6) M induced severe alterations in all parameters of the isolated hearts; the administration of DXR 3 mg/kg i.v. once a week for 3 weeks was associated with a widening of the S alpha T segment and QRS complex and cardiac histologic picture was markedly altered. In conclusion, distamycin A derivatives display elevated cytotoxicity while no substantial cardiotoxicity was observed.

Halo-cast treatment of fractures and dislocations of the cervical spine

Twenty-eight consecutive patients with dislocated, and often unstable, injuries of the cervical spine were treated by halo-cast stabilisation. One died and 27 were followed up. Twenty had no symptoms and 17 had full movement of the neck. There were only a very few minor complications. Seven patients had initial neurological impairment. They included the single death, but the remaining 6 regained useful muscle function. The halo-cast allows complete reduction in many types of fractures and dislocations, and good immobilisation is maintained.

Reducing doxorubicin cardiotoxicity in the rat using deferred treatment with ADR-529

The purpose of this study was to evaluate the optimal timing of ADR-529 administration to protect rats treated with doxorubicin (DXR) against drug-induced cardiotoxicity. Complete electrocardiographic monitoring (QRS complex, S alpha T segment and T wave) and the histopathological analysis of cardiac tissue were used to assess the degree of heart damage produced in female rats treated with ten i.v. doses of 1 mg/kg DXR over a period of 15 weeks; body-weight increase and survival were also analyzed to evaluate the toxicity of treatments. Cardiac alterations induced by DXR were compared with those occurring in animals receiving 20 mg/kg i.v. ADR-529 at 30 min prior to DXR administration, starting at the first, third, or sixth DXR dose and given until the end of the study (15th week). Rats treated with DXR were severely cardiomyopathic, showing progressive and irreversible ECG alterations (QRS-complex and S alpha T-segment widening and T-wave flattening) and marked degeneration of the myocardium (myocyte vacuolation, myofibrillar loss, and endomyocardial fibrosis). The most effective cardiac protection was provided by the administration of ADR-529 beginning with the first or third DXR dose. Delaying treatment with ADR-529 until the sixth DXR dose resulted in a significant reduction in its therapeutic action on heart damage. A significant difference in body-weight increase and survival was observed between the treatment groups: ADR-529 injected prior to the first DXR dose significantly protected animals from DXR toxicity, but this schedule was significantly more toxic than the administration of ADR-529 beginning with the third or sixth DXR dose. Taking into account the degree of cardiac protection and the toxicity of combination treatments, the results of the present study demonstrate the superiority of ADR-529 given prior to the third DXR dose over the other schedules tested. This finding suggests that significant protection against DXR-induced chronic cardiotoxicity in the rat can be obtained using deferred treatment with ADR-529.

In vivo activity of novel sulphonic derivatives of distamycin A

Solid tumor growth can be modulated through inhibition of vascularization elicited by angiogenic factors. With the objective to complex these factors, new derivatives of distamycin A were synthesized and evaluated in vitro [1] and in vivo for their ability, after i.v. administration, to inhibit bFGF-induced vascularization and the growth of M5076 murine reticulosarcoma implanted i.m. The tested compounds were able to block angiogenesis with inhibition values ranging between 70-100%. Moreover, they were found to be capable of inducing tumor inhibition with values ranging between 40% and 95% at non-toxic doses.

The epidemiology of fractures of the proximal end of the femur. Change in the incidence among the population at risk in the city of Perugia, Italy between the periods 1975-77 and 1986-88

The current interest in the epidemiology of fractures of the proximal end of the femur stems from a constant rise in their incidence in Western countries over the past several decades. Many authors believe the explanation could be an increased specific risk factor as well as an aging population. In the city of Perugia, Italy between 1975-77 and 1986-88 the incidence of these fractures increased by 108%, although the number of residents over 60 years of age increased by only 25%. An especially remarkable increase was seen in women over 70 and in intertrocherantic fractures. This information together with the National Institute of Statistics' (ISTAT) demographic forecasts regarding the aging Italian population lead to alarming epidemiologic projections for the next several decades. We propose two possible explanations for this increased risk factor: an increase in the frequency of falls suffered by elderly people and a deterioration in the quality of their bone.

Cardiotoxicity and cytotoxicity of the anthracycline analog 4'-deoxy-4'-iodo-doxorubicin

The cardiotoxicity and cytotoxicity of the novel doxorubicin (DXR) derivative 4'-deoxy-4'-iodo-DXR were evaluated and compared to DXR. A single dose of DXR 10 mg/kg i.v. in anesthetized rats induced a significant widening of S alpha T segment of the electrocardiogram, an increase in both mean arterial blood pressure and heart rate and a fall in systemic arterial dP/dtmax, while 4'-deoxy-4'-iodo-DXR 4 mg/kg i.v. induced a significant widening of S alpha T segment and an increase in mean arterial blood pressure. A chronic cardiomyopathy was induced over a 6-week period by three injections of DXR 3 mg/kg per week i.v. and was characterized by a progressive enlargement of S alpha T segment, a flattening of T wave, the occurrence of arrhythmias and histological alterations of myocardium. The contractile responses to adrenaline of isolated hearts from DXR-treated animals were significantly reduced compared to controls. 4'-Deoxy-4'-iodo-DXR (1.2 mg/kg per week three times) induced minor ECG alterations and sporadic episodes of arrhythmias. The contractile responses of isolated hearts were not significantly different from those of controls and microscopic examination of hearts revealed only minor changes. Cytotoxicity in vitro was evaluated by the colony formation assay; based on IC50, 4'-deoxy-4'-iodo-DXR was up to six times more cytotoxic than DXR on four human cancer cell lines. These results suggest that 4'-deoxy-4'-iodo-DXR is significantly less cardiotoxic and more cytotoxic than DXR.

Effects of cefamandole on hemostasis in patients undergoing hip replacement with heparin prophylaxis

The aim of this study was to compare the effects of the prophylactic use of cefamandole versus oxacillin plus gentamicin on hemostasis in patients undergoing hip replacement with heparin prophylaxis. Twenty-four patients with a normal hemostatic profile were randomly allocated to receive either cefamandole or oxacillin plus gentamicin. All the patients received calcium heparin. Platelet count, bleeding time, prothrombin time (PT), activated partial thromboplastin time (aPTT), thrombin clotting time (TCT), fibrinogen and serum FDP were assessed before treatment and every day of antibiotic administration. Surgical bleeding was assessed using a four-grade score system. Platelet count, bleeding time, fibrinogen and serum FDP did not show any change with both treatments. PT, aPTT and TCT showed a similar and mild prolongation in the two groups of patients. No difference in the surgical bleeding was observed between the two groups. We conclude that a short-term prophylaxis with cefamandole is a safe regimen in patients undergoing hip replacement with heparin prophylaxis.

Essential and non-essential amino acid requirement in injured patients receiving total parenteral nutrition

The metabolic derangements of injury are known to influence nitrogen (N) requirements whilst less is known about individual amino acid (AA) requirements. This study was designed to investigate prospectively N vs AA requirement in 36 injured patients treated with total parenteral nutrition (TPN). The non-protein caloric input was 30 kcal kg-1 day-1 and three AA solutions were assessed containing the same AAs but in different proportion. Overall N intake was set at 0.35 g N kg-1 day-1 for solution A and B and 0.24 g N kg-1 day-1 for solution C. Solution B was similar to A, both being enriched in branched chain AAs (BCAA: 0.69 g kg-1 day-1 in B compared with 0.55 g kg-1 day-1 in A) while decreased in aromatic and sulphurated forms (1.75 times the normal need). Solution C was designed to maintain a daily input of BCAA similar to A (0.52 g kg-1 day-1) but with the supply of aromatic and sulphurated AA between solutions A and B, the supply of other AAs (lysine, theonine, histidine, arginine, glycine) being dependent on the selected N intake. For all the essential AAs the supply was always greater than normal allowances. Increasing BCAA over 0.55 g kg-1 day-1 did not improve N balance when N intake was 0.35 g kg-1 day-1, whilst nutrition with solution C was unable to maintain N balance. Moreover we found indirect evidence that this N intake, 0.52 g kg-1 day-1 was more sparing than 0.37 g kg-1 day-1 of BCAA.(ABSTRACT TRUNCATED AT 250 WORDS)

Fractures of the acetabulum: conservative treatment and results

The treatment of fractures of the acetabulum is still a controversial subject. There has in recent years been a tendency towards surgical rather than conservative treatment but more recently it has been observed that the long-term results of both types of treatment are not dissimilar. The classification of these fractures is important in relation to both conservative and surgical treatment. With the objective of rationalising the choice of treatment, 72 comminuted fractures of the acetabulum treated conservatively at the Orthopaedic Clinic in Perugia between 1959 and 1980 were reviewed. Both the clinical and radiographic features of these cases were analysed. The overall results were 70% successes and 30% failures. Several correlations indicating which features of the fracture had most influence on the final results were established; the involvement of the support surfaces (acetabular dome) and joint congruency were found to be the most important. In addition to these major factors, the age of the patient, presence or absence of dislocation, the degree of displacement and topography of the fragments collectively define the "type" of fracture and the criteria which are indispensable for the choice of treatment.

Rapidly progressive osteoarthritis of the hip

Osteoarthritis of the hip is rapidly progressive in 5% of cases, particularly in patients of advanced age. At times there is total destruction of the femoral head. Nineteen such cases are described and the literature is reviewed. The clinical picture is dominated by rapidly progressive pain and limping; the radiographic picture by the absence of osteophytosis. The pathology of rapid progression is subdivided into primary and secondary. Several hypotheses of the pathogenesis are discussed. These are related to mechanical overloading factors, local cortisone therapy, anoxia, synovitis. Differential diagnosis is with subacute septic arthritis, monarticular rheumatoid arthritis, and idiopathic osteonecrosis of the femoral head. Prosthetic replacement is the only treatment indicated and the long-term results do not differ from those obtained in prosthetic replacement for the more common type of osteoarthritis.

The influence of amrinone on cardiac toxicity induced by adriamycin in rats

The influence of amrinone (AM), a positive inotropic drug, on cardiotoxicity induced by repeated adriamycin (ADR) administration, was studied in rats. AM, administered at various doses, did not affect rat body weight gain, heart rate, electrocardiographic parameters (QRS complex, S alpha T segment, T-wave), or the histological cardiac picture. By contrast, ADR markedly inhibited rat body weight increase and induced the appearance of early ECG alterations, especially S alpha T widening, as well as morphological cardiac changes consisting of macrovacuolation of myocytes, atrophy, necrosis and fibrosis. When given with ADR, AM reduced the toxicity of ADR limiting the deleterious effects of the drug on body weight gain and delaying the appearance of ECG abnormalities, particularly S alpha T widening and T-wave flattening. The severity of cardiac lesions histologically evaluated at the end of the experiment, however, was similar in rats given ADR or AM plus ADR. These results may be explained by taking into account the ability of AM to increase the Ca2+ influx through the slow channels in myocardial cells, thus counteracting the decreased inward slow Ca2+ currents due to ADR. The failure of AM to improve histological cardiac alterations significantly, seems to indicate that among the numerous pathogenetic mechanisms of ADR-induced cardiotoxicity, the changes in cellular Ca2+ fluxes play an important, but not a fundamental role.

General and cardiac toxicity of adriamycinol in rats

The toxic effects of adriamycinol, the main metabolite of adriamycin, were studied during repeated treatment in rats, by evaluating survival, body growth, electrocardiographic parameters and cardiac histopathology. Different groups of animals were treated with 3 mg/kg weekly of adriamycinol or adriamycin for the first 3 weeks of the experiment and were observed for a further period of 4 weeks. One adriamycinol-treated rat and two adriamycin-treated ones died during the experiment. Adriamycinol inhibited rat body weight increase and induced the appearance of ECG alterations (especially S alpha T widening) as well as moderate histological cardiac lesions, but to a lesser extent and severity compared with adriamycin, which, in turn, markedly affected rat body growth, ECG parameters (especially the S alpha T segment and the T-wave) and the histological cardiac picture. The data of the present study indicate that adriamycinol induces an adriamycin-like toxic syndrome mainly affecting the heart, although to a lesser degree of severity than the parent drug. The lower toxic potential displayed by the metabolite might be due to its greater polarity compared with adriamycin, which implies a lower uptake of adriamycinol into tissues, especially the heart.

Neuralgic amyotrophy of the shoulder girdle. The Parsonage-Turner syndrome

From 1971 to 1983 we observed 58 cases of the Parsonage-Turner syndrome. This is a neuromuscular disease of the shoulder girdle and upper extremity which up to now has been dealt with almost exclusively in the French and Anglo-Saxon literature. The aetiology remains obscure. It is characterised by pain of acute and violent onset with paralysis and wasting of the muscles of no specific nerve root distribution. The diagnosis is based on clinical examination and electromyography. The prognosis is usually favourable. The differential diagnosis and treatment are discussed.

Parenteral nutrition of injured patients: Effect of manipulation of aminoacid infusion (increasing branched chain while decreasing aromatic and sulphurated aminoacids)

Sixteen critically ill injured patients received parenteral nutrition providing nitrogen (0.34 g kg(-1) day(-1)) and glucose (32 kcal kg(-1) day(-1)) for 5 days. They were randomly divided into two groups with respect to aminoacid supply: an essential aminoacid solution vs the same solution enriched in branched chain amino acid (BCAA) content and decreased in phenylalanine and methionine content (mean BCAA intake, 0.55 vs 0.69 g kg(-1) day(-1)). Basal values of nitrogen metabolism without treatment showed no difference between the two groups. Nitrogen losses and 3 methylhistidine (3-MEH) excretion were elevated; the plasma aminoacid pattern was altered by the trauma and except for phenylalanine, aspartate and glutamate, plasma aminoacid concentrations were decreased below normal values. Net muscular aminoacid output was demonstrated by femoral arterio-venous (av) differences that were all negative except for glutamate and citrulline TPN with both solutions improved the nitrogen balance and reduced the negative aminoacid balance across the leg. Adjusting a TPN regimen to increase the BCAA content without altering the total nitrogen infused, had no effect on overall nitrogen balance, but exerted a beneficial effect on body protein catabolism, as assessed by the urinary 3-MEH excretion rate, and a transient improvement in the aminoacid balance across the leg at the peak of the infusion. The short-lived effect of BCAA suggest a metabolic effect of these aminoacids which deserves further study.

Stable fixation of fractures of the forearm in adults

The results are presented of 148 fractures of the radius and ulna in 89 patients. All were treated by AO compression plating. The results were assessed at an average of 4.5 years. In 80% of cases these were functionally excellent and confirm that this method of treatment gives early consolidation and restoration of good function in adults. However, there is a significant percentage of complications in open fractures of both bones.

Results of rigid fixation in 54 supracondylar fractures of the femur

We present the results of the internal fixation in 48 supracondylar fractures of the femur with a follow-up of 1 to 10 years. These fractures have been classified according to the criteria proposed by the AO international. The clinical results were excellent to good in 70.9% of the cases, fair to bad in 22.9%, and failures (due to pseudarthrosis and osteomyelitis) in 6.2%. Significantly inferior results were obtained in articular, open, and imperfectly reduced fractures. The frequent comminution of these fractures often interfered with anatomic reduction, which explains the elevated number of consolidations in varus and/or recurvation.