Renal and electrolyte disturbances associated with cisplatin

Cisplatin is a coordinate metal complex with significant antineoplastic activity and various effects, including acute anc chronic renal insufficiency and renal magnesium wasting. Nephrotoxicity may occur in as many as 50% to 75% of patients receiving the drug, and is apparently due to renal tubular injury. Although controlled, prospective clinical trials are lacking, the available data indicate that the frequency and severity of cisplatin nephrotoxicity may be reduced by slow infusion rates; hydration before, during, and immediately after administration of cisplatin; and concomitant administration of mannitol. Preliminary animal studies indicate that chloride-containing vehicles such as 0.9% sodium chloride may prevent the aquation or hydroxylation of cisplatin and reduce its toxicity. No information is available on th prevention of cisplatin associated renal magnesium wasting. However, frequent measurement of serum cations and appropriate replacement are recommended.

Increased urinary excretion of LTE4 after exercise and attenuation of exercise-induced bronchospasm by montelukast, a cysteinyl leukotriene receptor antagonist

BACKGROUND

A study was undertaken to determine whether montelukast, a new potent cysteinyl leukotriene receptor antagonist, attenuates exercise-induced bronchoconstriction. The relationship between the urinary excretion of LTE4 and exercise-induced bronchoconstriction was also investigated.

METHODS

Nineteen non-smoking asthmatic patients with a forced expiratory volume in one second (FEV1) of > or = 65% of the predicted value and a reproducible fall in FEV1 after exercise of at least 20% were enrolled. Subjects received placebo and montelukast 100 mg once daily in the evening or 50 mg twice daily, each for two days, in a three-period, randomised, double blind, crossover design. In the evening, approximately 20-24 hours after the once daily dose or 12 hours after the twice daily dose, a standardised exercise challenge was performed. Data from 14 patients were available for complete analysis.

RESULTS

The mean (SD) maximal percentage decrease in FEV1 after exercise was 29.6 (16.0), 17.1 (8.2), and 14.0 (9.4) for placebo, once daily, and twice daily regimens, respectively. The mean (95% CI) percentage protection was 37 (15 to 59) for the group who received 50 mg twice daily and 50 (31 to 69) for those who received 100 mg once daily. Active treatments were not different from each other. The mean (SD) plasma concentrations of montelukast were higher after the twice daily regimen (1.27 (0.81) microgram/ml) than after the once daily regimen (0.12 (0.09) microgram/ml); there was no correlation between the percentage protection against exercise-induced bronchoconstriction and plasma concentrations. After exercise urinary excretion of LTE4 increased significantly during placebo treatment (from 34.3 to 73.7 pg/mg creatinine; p < 0.05) but did not correlate with the extent of exercise-induced bronchoconstriction.

CONCLUSIONS

Montelukast protects similarly against exercise-induced bronchoconstriction between plasma concentrations of 0.12 and 1.27 micrograms/ml. The increase in the urinary excretion of LTE4 after exercise and the protection from exercise-induced bronchoconstriction with a cysteinyl leukotriene receptor antagonist provide further evidence of the role of leukotrienes in the pathogenesis of exercise-induced bronchoconstriction.

Acute dentoalveolar infections: an investigation of the duration of antibiotic therapy

OBJECTIVE

To evaluate shortened courses of antibiotics in the management of dentoalveolar abscesses.

DESIGN

Prospective clinical study over a 3-year period.

SETTING

Examinations department of the Liverpool University Dental Hospital.

SUBJECTS

759 patients, with acute dentoalveolar abscesses associated with swelling, and an elevation of axillary temperature to above 38.5 degrees C, were included in the investigation. The minimum age of the patients was 16 years.

INTERVENTIONS

The initial treatment was to drain the abscess by incision (124 patients), or extraction (635). The patients were prescribed amoxycillin (250 mg every 8 hours), clindamycin (150 mg every 6 hours) or erythromycin stearate (250 mg every 6 hours) and instructed to drink plenty of fluid. All the patients were seen 2 or 3 and 10 days later; only patients who were seen at these times were included in the trial.

MAIN OUTCOME MEASURES

Resolution of the swelling and a normal axillary temperature.

RESULTS

At first review 748 patients (98.6%) had normal temperatures, marked resolution of the swelling and the antibiotic was discontinued. None of these 748 patients required further antibiotic therapy.

CONCLUSIONS

The duration of antibiotic therapy in most patients with acute dentoalveolar infections can safely be 2-3 days, provided that drainage has been established. It is not, therefore, necessary for the majority of patients to complete a 5-day course of antibiotics.

Treatment of advanced-stage massive mediastinal Hodgkin's disease: the case for combined modality treatment

In the initial series of 198 patients treated at the National Cancer Institute (NCI) with mechlorethamine, vincristine, procarbazine, and prednisone (MOPP) chemotherapy for Hodgkin's disease, a review of presenting chest radiographs available on 192 of these patients showed 49 patients with mediastinal masses greater than one third the greatest posteroanterior chest diameter. Five patients had stage IIB disease, and 44 had stage III or IV disease. Thirty-five (71%) patients achieved a complete remission with MOPP chemotherapy. Fourteen (40%) of the complete responders relapsed, but four of these achieved durable remissions in response to subsequent therapy. Thirty (61%) patients have died (14 induction failures, nine relapsed patients, seven complete responders in remission). Thus, with a median follow-up of 20 years (range, 15 to 23), the overall survival for the group is 39%, and the disease-free survival for the complete responders is 60%. A subset of 10 patients received mantle radiation therapy after maximal response to MOPP. One of these patients failed to achieve complete remission, but among the nine complete responders only one has relapsed. In contrast, 13 of 26 (50%) patients achieving a complete response to MOPP alone have relapsed (P2 = .0536). Although MOPP alone was not prospectively compared with MOPP plus radiation therapy in the treatment of advanced-stage massive mediastinal Hodgkin's disease in this series, the retrospective analysis shows a nearly significant difference in disease-free survival favoring combined modality treatment. The difference in tumor mortality between MOPP-treated (44%) and combined modality-treated patients (80%) was also nearly significant (P2 = .055). However, overall survival differences between patients treated with MOPP alone and those treated with combined modality therapy were not significantly different (P2 = 0.23) because of the mortality related to late complications of combined modality treatment.

Neurologic complications of disseminated intravascular coagulation

Sixty-five patients with a bleeding disorder and coexistent neurologic abnormalities were examined over a 4-year period to determine: (1) the CNS pathology due to disseminated intravascular coagulation (DIC); (2) the clinical setting in which CNS dysfunction due to DIC occurs; and (3) the neurologic complications of DIC as opposed to those patients dying with concurrent DIC. Criteria for inclusion in the study were the combination of: (1) a neurologic disorder in a patient with clinical evidence of a bleeding disorder; and (2) evidence of DIC by laboratory criteria or the detection of fibrin thrombi in multiple organs at postmortem. Twenty-four of 65 patients met these diagnostic criteria, including 14 men and 10 women, aged 24 to 84 years. Autopsies were obtained in 17 patients. These patients were divided into two groups Group I consisted of 10 patients with evidence of cerebral bleeding or infarction at the onset of DIC. Group II consisted of 14 patients who met the diagnostic criteria for DIC but did not demonstrate postmortem evidence of hemorrhage or infarction in the brain. Patients with malignancy who present with findings suggestive of a large-vessel stroke are likely to have DIC and nonbacterial thrombotic endocarditis. The most common neurologic complications of DIC are large vessel occlusion, obtundation and coma, subarachnoid hemorrhage, and multiple cortical and brainstem hemorrhages and infarction.

Is the mammosomatotrope a transitional cell for the functional interconversion of growth hormone- and prolactin-secreting cells? Suggestive evidence from virgin, gestating, and lactating rats

Serum concentrations of PRL and GH increase and decrease, respectively, during the progression from nonpregnancy through lactation. However, it is unknown whether the secretory capacities and/or relative abundance of cells that release PRL or GH are altered during these physiological states. In the present study anterior pituitaries from adult virgin, gestating, and early or late lactating female rats were dispersed with trypsin and subsequently assayed for PRL and GH release using reverse hemolytic plaque assays. We found that the relative abundance of PRL-secreting cells was greater and that of GH cells lower in pituitaries from lactating females than in those from virgins. Moreover, the relative amounts of both PRL and GH released per cell were diminished in gestating and lactating females. For PRL, this decrease could be accounted for by an increase in the number of cells that released small quantities of hormone. We then performed simultaneous plaque assays to determine whether the shifts in the relative proportions of PRL and GH secretors were due to changes in the percentages of cells that secrete each hormone alone or in the fraction that releases both PRL and GH concurrently. Variations in both single and dual hormone-secreting cells appear to contribute to the overall fluctuations in the relative abundance of PRL and GH cells during these physiological transitions. We conclude that the additional PRL secretors present during lactation may arise from cells that previously released only GH, and that this functional interconversion of GH and PRL secretors might involve an intermediate cell type, the mammosomatotrope.

Lethal multiple pterygium syndrome: three consecutive cases in one family

We report on three sib fetuses with the lethal multiple pterygium syndrome (LMPS), one case occurring in a twin pregnancy. All three fetuses had a cystic hygroma and hydrops was detected by ultrasound. The classification scheme for LMPS proposed by Hall [1984] is examined. With our present state of knowledge of this syndrome, subdivision on bone-fusion types does not appear to be justified. Antenatal detection by ultrasound is possible in most pregnancies with a second affected fetus because of cystic hygroma and hydrops. In the term or near-term infant in which ultrasound has not shown cystic hygroma or hydrops, a diagnosis of Pena-Shokeir type I syndrome should be considered because pterygia are a component of that syndrome but cystic hygroma and hydrops are not.

Amethod for measuring deviations from equilibrium of the glucose anomers in blood

A method for detecting deviations from equilibrium values of β-d-glucose has been developed. This method is dependent upon the specificity of glucose-oxidase for β-d-glucose and the catalytic effect of hydroxyl ions on mutarotation. The method has been used to monitor the blood stream of anesthetized normal dogs and dogs given epinephrine, glucagon, or insulin. It has also been used with alloxan-diabetic dogs. Since the method will detect deviations from equilibrium when agr- or β-d-glucose infusions are given and since in the above situations no impressive deviations were seen, it has been concluded that in the anesthetized dog the glucose is at or very near equilibrium and that glucagon and epinephrine do not alter the equilibrium.

monitoring blood glucose; epinephrine on glucose anomers; glucagon on glucose anomers; insulin on glucose anomers

Submitted on August 24, 1964

A deletion in the long arm of chromosome 18 in a child with serum carnosinase deficiency

The dipeptides carnosine and anserine, found exclusively in meats, are hydrolyzed in serum by the enzyme carnosinase. Several reports of serum carnosinase deficiency describe a variable phenotype, which ranges from normal to severe psychomotor retardation, hypotonia, and myoclonic seizures in the first year of life. We report the case of a 30-mo-old girl with hypotonia, developmental delays, and tremor. Although consuming nominal quantities of meal, she excreted large amounts of carnosine and anserine. A strict meat-free diet ameliorated, but did not eliminate, these abnormalities. Serum carnosinase activity was found to be extremely low. Analysis of this child's chromosomes revealed a terminal deletion of chromosome 18 with breakpoint at q21.3. Neither parent exhibited this deletion, suggesting it was generated de novo in the patient or in a parental germ cell. Molecular studies showed that the patient's paternal chromosome 18 was deleted. Urinary carnosine excretion and serum carnosinase activity were normal in the patient's father. The mother had low carnosinase activity. The patient's brother exhibited moderate hypercarnosinuria and intermediate enzyme activity, consistent with the carrier state for carnosinase deficiency. Cumulatively, these findings suggest that the locus for this enzyme resides on the distal long arm of chromosome 18, and they are consistent with an unusual mechanism for the inheritance of this, typically autosomal recessive, condition. We conclude that this patient is likely hemizygous for the defect, having received the deficiency allele from her mother and, by virtue of the chromosomal deletion, no allele from her father. This represents the first report of a chromosomal abnormality in association with serum carnosinase deficiency and should aid in further localization of the gene encoding serum carnosinase.

Indium-111 monoclonal antibody B72.3 scintigraphy in colorectal cancer. Correlation with computed tomography, surgery, histopathology, immunohistology, and human immune response

As part of an open-labeled nonrandomized multi-institutional Phase III study, the authors compared the results of In-111 (In-111) B72.3 glycyl-tyrosyl-n-diethylenetriaminepentaacetic acid lysine (GYK-DTPA) monoclonal antibody scintigraphy with computed tomography (CT), surgery, histopathology, immunohistology, and human antibody response in 23 patients with primary colorectal carcinoma. There were no significant adverse reactions to 1 mg of In-111-labeled antibody. Planar imaging identified 16 of 23 primary colon lesions, whereas single photon emission computer tomography (SPECT) imaging identified 21. SPECT also correctly identified lymphatic involvement in four patients. (There were two false-positive results.) Liver metastases were identified with SPECT imaging. Twenty-six percent of patients developed human anti-mouse antibody (HAMA). These preliminary results demonstrate that In-111 B72.3 GYK-DTPA is a safe monoclonal antibody conjugate that has a high sensitivity for identifying primary colorectal cancer. Regional lymphatic and distant liver metastases also can be imaged, but false-positive results can occur.

Experience with long-term outpatient venous access utilizing percutaneously placed silicone elastomer catheters

One hundred forty consecutive cancer patients had percutaneously placed subclavian vein catheters for up to 882 days' duration. The incidence of suspected and proven catheter-related sepsis was low. This is a cost-effective alternative to tunneled catheter insertion for chronic venous access in cancer patients.

Suckling unmasks the stimulatory effect of dopamine on prolactin release: possible role for alpha-melanocyte-stimulating hormone as a mammotrope responsiveness factor

Mounting evidence indicates that dopamine (DA) can stimulate as well as inhibit PRL release when given in appropriately low doses. In the present study, we investigated whether the suckling stimulus could influence this response. Pituitary cultures from suckled or nonsuckled rats were exposed to DA (10(-16) - 10(-6) M) during a reverse hemolytic plaque assay for PRL. Pituitary cells from nonsuckled rats exhibited only the inhibitory response to DA; exposure to high-dose DA (10(-6) M) reduced plaque area to 42.3 +/- 7.2% (mean +/- SEM) of control. A low dose of DA (10(-12) M) had no effect on PRL secretion (79.3 +/- 13.3% of control). In striking contrast, a brief suckling stimulus (10 min) rendered the mammotropes responsive to stimulation by low-dose DA (to 152.7 +/- 12.5% of control). Thus, suckling appears to be a requirement for expression of the stimulatory effect of DA in lactators. In a subsequent series of experiments we explored the possibility that a hypophysial factor, released during nursing, might mimic the effects of suckling on mammotrope responsiveness. Accordingly, we tested the effects of alpha-melanocyte-stimulating hormone (10(-7) M) and low-dose DA, alone or in combination, on pituitary cells from nonsuckled rats. Although neither agent alone had a dramatic effect on PRL secretion, concurrent administration of both of these significantly stimulated PRL release to 130.0 +/- 4.2% of control. Taken together, these results demonstrate that suckling renders mammotropes responsive to the stimulatory effects of DA. Moreover, our data indicate that alpha-melanocyte-stimulating hormone could function as a responsiveness factor in this phenomenon.

Antithyroid effects of coal-derived pollutants

Endemic goiter in iodide-sufficient areas of the United States and Colombia has been linked to watersheds rich in coal and shale, which several reports suggest are the source of water-borne goitrogens. In this report the potential antithyroid activities of aqueous coal and shale extracts and of compounds identified in aqueous effluents from coal conversion processes were assayed in thyroid peroxidase (TPO) and thyroid slice systems. Aqueous extracts of coal and black shale were potent inhibitors of TPO or 125I organification by thyroid slices. The most abundant water-soluble compounds derived from coal are dihydroxy-phenols, thiocyanate, disulfides, and hydroxypyridines. The dihydroxyphenols resorcinol, 2-methylresorcinol, and 5-methylresorcinol (orcinol) were 26.7, 22.5, and 7.2 times more potent, respectively, than the antithyroid drug 6-propylthiouracil (PTU). Other dihydroxyphenols and thiocyanate were less potent but comparable in activity to PTU. All dihydroxypyridines and 3-hydroxypyridine produced inhibitory effects comparable to PTU. None of the disulfides inhibited TPO. The antiperoxidase effects of combinations of two dihydroxyphenols or one dihydroxyphenol and SCN were additive, whereas the effects of a combination of four dihydroxyphenols at threshold inhibitory concentrations were synergistic, resulting in net effects equivalent to or greater than the sum of the individual effects. Thus, antithyroid effects may be greatly amplified by exposure to multiple coal-derived goitrogens and could be many times that produced by any one of the contributing pollutants. These results demonstrate that potent water-borne goitrogens are derived from coal and shale and that their contamination of water supplies could pose a serious threat of thyroid disorders.

Intravenous gamma globulin in the treatment of chronic idiopathic thrombocytopenic purpura in adults

Eight adult patients with chronic idiopathic thrombocytopenic purpura have been treated with an intravenous gamma globulin preparation. All patients received at least one "induction" course of intravenous gamma globulin for five consecutive days at a dose of 400 mg/kg per day. There were a total of 12 induction treatments. In five instances, patients also received single "maintenance" infusions of intravenous gamma globulin at the same dose. The mean peak increment in platelet count (X 10(3)/microliters) after induction was 87.3 +/- 42.37; after maintenance therapy it was 62.2 +/- 12.99. In only one instance was the platelet count increment less than 50 X 10(3)/microliters. In 13 of 17 intravenous gamma globulin treatments (both induction and maintenance), the platelet count returned to baseline or near-baseline levels within one to two weeks. In four instances, more prolonged remissions were observed. Measurements of platelet-associated IgG demonstrated the following: when platelet-associated IgG was greater than 100 ng/10(6) platelets, platelet-associated IgG usually decreased markedly after intravenous gamma globulin therapy. When platelet-associated IgG was less than 20 ng/10(6) platelets, platelet-associated IgG usually increased with therapy. There was no correlation between starting platelet-associated IgG levels or changes in platelet-associated IgG levels with therapy and the increment in the patient's platelet count.

Relative importance of newly synthesized and stored hormone to basal secretion by growth hormone and prolactin cells

It is generally accepted that under basal conditions there is preferential release of newly synthesized hormone by a number of endocrine cell type, including those that secrete GH or PRL. However, the cellular basis for this phenomenon along with the relative contribution of stored hormone to basal secretion has yet to be clearly established. In the present study, we employed reverse hemolytic plaque assays to monitor basal and stimulated release of GH and PRL from individual cells in which de novo protein synthesis had been blocked. Monodispersed pituitaries from adult male rats were cultured for 21 h in the absence or presence of maximally effective doses of puromycin (100 microM) or cycloheximide (36 microM) and were then subjected to separate plaque assays for GH or PRL. Treatment with puromycin reduced the percentage of GH or PRL secretors (plaque formers) by about half. Coincubation with stimulatory secretagogues did not increase the percentages of GH or PRL secretors in control cultures, but returned the proportion in puromycin-treated cells to normal, demonstrating that cells which failed to secrete basally could still release hormone from their stored pools when stimulated. Very similar results were obtained when these experiments were repeated with cycloheximide. Taken together, these results demonstrate that only a fraction of the cells that release GH or PRL are dependent upon newly synthesized hormone for basal secretion; the remainder appear capable of mobilizing stored hormone for this purpose even in the absence of stimulation.

Efficacy of activated charcoal hemoperfusion in removing lethal doses of barbiturates and salicylate from the blood of rats and dogs

Rats were injected intraperitoneally with lethal doses of sodium pentobarbital (115 mg/kg) or a lethal mixture of sodium salicylate (500 mg/kg) and sodium acetazolamide (25 mg/kg). Within about 20 min, part of each group was connected to an extracorporeal circuit containing uncoated activated charcoal and part to an empty control circuit. After a 90-min hemoperfusion, the treated groups showed a significantly decreased mortality (58% to 14% for pentobarbital; 100% to 0% for salicylate). Dogs were injected intravenously with lethal doses of sodium phenobarbital (175 mg/kg). One group was treated by hemoperfusion through an empty device in a control extracorporeal circuit, a second group was treated with loose-bed activated charcoal devices, and a third group with fixed-bed activated charcoal devices. For both the fixed and loose-bed devices, a 5-h hemoperfusion markedly decreased mortality (100% to less than or equal to 15%). The lethal combination of salicylate and closed-circuit methoxyflurane anesthesia was also successfully treated in dogs. This study clearly demonstrates the lifesaving potential of uncoated activated charcoal hemoperfusion.

Hepatotoxicity with antiretroviral treatment of pregnant women

BACKGROUND

Hepatotoxicity in adults with human immunodeficiency virus (HIV) infection has been associated with all classes of antiretroviral drugs and coinfection with hepatitis B and C virus. We treated two HIV-infected pregnant women in whom hepatotoxicity developed after initiating antiretroviral therapy.

CASES

The first woman developed icterus, jaundice, hyperbilirubinemia, and elevated serum aminotransferase levels approximately 5 months after beginning combination antiretroviral therapy with zidovudine, lamivudine, and efavirenz. Serum aminotransferase abnormalities improved after discontinuation of antiretroviral medications. The second woman had similar symptoms and laboratory abnormalities 3 months after initiation of zidovudine, lamivudine, and nelfinavir. Despite initial improvement after discontinuing her antiretroviral medications, fulminant hepatic failure developed and she died. Both patients tested negative for hepatitis A, B, and C; Epstein-Barr virus; and cytomegalovirus. There was no history of illicit drug use, alcohol use, or blood transfusions in either case.

CONCLUSION

We emphasize the need for careful monitoring for hepatotoxicity after initiation of antiretroviral therapy.

Does alpha-melanocyte-stimulating hormone from the pars intermedia regulate suckling-induced prolactin release? Supportive evidence from morphological and functional studies

Recent evidence suggests that substances derived from the hypophyseal intermediate lobe (IL) play a crucial role in the regulation of suckling-induced PRL secretion. The purpose of the present study was to explore this possibility further by determining whether the suckling stimulus acutely increases the secretory activity of the IL and whether alpha MSH, a major secretory product of the IL, plays a specific role in suckling-induced PRL release. Light microscopic morphometric analysis of serial pituitary sections obtained from lactating rats revealed that as little as 1 min of suckling caused a significant increase in the proportion of the IL that was in secretory configuration (11.8 +/- 0.7% vs. 6.7 +/- 0.5%; 1-min suckled vs. nonsuckled control; mean +/- SE). Moreover, the fraction of the IL in secretory configuration continued to increase after 5 and 10 min of nursing (to 16.0 +/- 0.8% at 5 min and 18.2 +/- 0.7% at 10 min). In contrast, serum PRL was not significantly elevated above the control level after 1 min of suckling (18.1 +/- 13.5 vs. 9.9 +/- 6.5 ng/ml, 1-min suckled vs. control). In fact, a significant rise in PRL levels (to 314.4 +/- 19.4 ng/ml) could be detected only after 10 min of nursing. Thus, secretion by the IL in response to suckling preceded the release of adenohypophyseal PRL, suggesting that a secretory product(s) from the pars intermedia is involved in the modulation of nursing-induced PRL release. Having established a sequential temporal relationship between these two phenomena, we next investigated whether alpha MSH was the IL factor involved in the regulation of suckling-induced PRL secretion. To this end, lactating rats were injected either with antiserum to alpha MSH or preimmune serum and then allowed to nurse their pups. Serial blood samples were taken from the mothers 15, 30, 60, and 90 min after the litters were returned, and serum PRL was measured by RIA. We found that the suckling-induced rise in serum PRL was severely attenuated in animals that received anti-alpha MSH serum. This suppression was most evident at 15 min (70.1 +/- 13.4 vs. 323.5 +/- 127.0 ng/ml, antibody treated vs. preimmune serum control) and persisted throughout the entire 90-min test period. When taken together, our results suggest that suckling-induced PRL secretion is mediated at least in part by alpha MSH released from the hypophyseal IL.