Effect of intracarotid infusion of etoposide with angiotensin II-induced hypertension on the blood-brain barrier and the brain tissue

This study investigated the effects of the intracarotid infusion of etoposide in combination with angiotensin II (AT II)-induced hypertension on the blood-brain barrier (BBB) and brain tissue in rats. Eighty rats were divided into five groups: Group 1, intravenous infusion of AT II to increase arterial blood pressure; Group 2, intracarotid infusion of etoposide at 22.5 mg/m2 for 10 minutes; Group 3, intracarotid infusion of etoposide at 75.0 mg/m2 for 10 minutes; Group 4, intracarotid infusion of etoposide at 75.0 mg/m2 for 20 minutes; Group 5, intracarotid infusion of etoposide at 75.0 mg/m2 for 10 minutes with AT II-induced hypertension. Evans blue staining of the brain was used as a monitor of BBB disruption. Mean arterial blood pressure over the experimental period in Group 1 increased from 86.3 +/- 1.3 mmHg (mean +/- SEM) to 139.0 +/- 2.4 mmHg, and Group 5 from 85.9 +/- 1.8 mmHg to 137.3 +/- 2.4 mmHg. None of the animals in Group 1 and 2 showed any obvious neurological change, while all the animals in Group 3, 4 and 5 exhibited diminished activity as their sole neurological change throughout the course of the experiment. Slight evidence of BBB disruption was seen in only 25% of the animals in Group 1. Significant BBB disruption was found in the animals in Group 2, 3, 4 and 5. No histological change was observed in any animal in Group 1 and 2.(ABSTRACT TRUNCATED AT 250 WORDS)

Retinal blood flow alterations associated with scleral buckling and encircling procedures

The bidirectional laser Doppler technique and monochromatic photography were used to measure the absolute blood flow rate in the major temporal retinal arteries in seven patients following unilateral scleral buckling and encircling procedures, and in two patients before and after removal of scleral buckling elements. In the seven patients who had undergone uncomplicated scleral buckling procedures the arterial flow rates were on average 50% lower (p = 0.01) in the surgically treated eyes than in the contralateral eyes. Removal of scleral buckling elements in two patients produced increases of 73% and 44% in arterial blood flow rates.

Intracranial metastasis from a spinal cord primitive neuroectodermal tumor: case report

A patient with intracranial seeding from a spinal cord primitive neuroectodermal tumor with ependymal differentiation is presented. The first and second stages of intracranial dissemination were well controlled by a combination of irradiation and chemotherapy. The authors review previously published cases and discuss the possible mechanism of seeding from the spinal cord to the intracranial region.

Induction of colon adenocarcinomas in CD rats and lung adenomas in ICR mice by 6-nitrochrysene: comparison of carcinogenicity and aryl hydrocarbon hydroxylase induction in the target organs of each species

Species and organ specificity of 6-nitrochrysene (6-NC)-induced carcinogenicity and the potential correlation with aryl hydrocarbon hydroxylase (AHH) induction in the target organs were investigated in both sexes of ICR mice and CD rats. Animals received total 6-NC doses of 1.4 mumol/mouse and 14.8 mumol/rat. The first i.p. injection was performed within 24 h of birth, then the animals were subjected to 3 and 5 weekly injections in the mouse and rat cases, and the survivors were sacrificed at weeks 24 and 32, respectively. Adenocarcinomas and dysplasias and/or adenomas of the colon in rats and lung adenomas in mice were observed in animals treated with 6-NC. However, no such lesions were observed in animals treated with the vehicle dimethyl sulfoxide alone. AHH activities in the lung, colon, and liver of each animal after treatment with 6-NC or dimethyl sulfoxide were also investigated. Six-week-old animals received a single 6-NC injection i.p. at the dose of 0.8 mumol/mouse or 8.0 mumol/rat. Animals were sacrificed on day 1 or 7 following injections, when AHH levels were measured. The results indicated enzyme levels in all these organs to be elevated by 6-NC treatment, the induction rate in the mouse lung being the highest. These results showed that 6-NC is carcinogenic for the colon of rats, as well as the lung of mice, and that it also induces AHH activity in both target and nontarget organs.

Retinal detachment after cataract surgery. Surgical results

The authors studied the results obtained by the Retina Associates in 376 eyes of 361 patients operated on for retinal detachment associated with aphakia or pseudophakia with a postoperative follow-up of at least 6 months. All eyes underwent scleral buckling. The series included 103 eyes with aphakia, 17 eyes with iris-fixated intraocular lens, 111 eyes with anterior chamber (AC) IOL, and 145 eyes with posterior chamber (PC) IOL. The overall success rate for retinal detachment was 93%, without significant difference among the different groups. The aphakia and PC IOL groups had significantly higher prevalence (63% and 60%, respectively) of visual acuity equal to or better than 20/40 compared with the AC IOL group (33%). The prevalence of postoperative corneal edema in the AC IOL group was significantly higher than in the aphakia and PC IOL groups. Preoperative vitreous hemorrhage, large retinal breaks, posterior retinal breaks, total retinal detachment, proliferative vitreoretinopathy, and the need for performing a closed vitrectomy were significant factors in predicting ultimate failure.

Retinal detachment after cataract surgery. Predisposing factors

The authors studied the characteristics of 376 eyes of 361 patients with primary retinal detachment (RD) and surgical aphakia (103 eyes) or pseudophakia (273 eyes). Of the pseudophakic eyes, 17 had an iris-fixated intraocular lens (IOL), 111 had an anterior chamber (AC) IOL, and 145 had a posterior chamber (PC) IOL. Of the PC IOL cases, 48 (33%) had undergone YAG capsulotomy, and 46% of them developed RD within 6 months after capsulotomy. The frequency of no breaks found in pseudophakic RD (15%) was significantly higher than in RD with simple aphakia (5%). The most frequent reasons were incomplete fundus view due to a small pupil in the iris-fixated (83%) and the AC (44%) groups, and cloudiness of capsular remnants in the PC group (78%). In pseudophakic RD, sizable single tears, located more posteriorly than in RD with simple aphakia, were frequent. The authors speculate that in pseudophakic RD the retinal breaks may resemble those noted in phakic RD.

[Idiopathic plasmacytic lymphadenopathy with polyclonal hyperimmunoglobulinemia with elevated level of serum interleukin-6]

A 38-year-old male was admitted in January 1984 due to lymphadenopathies with hyperimmunoglobulinemia with a serum IgG level of 2,872 mg/dl. Following this, he was observed as an outpatient in regard to lymphadenopathies of unknown origin. In 1989, after the fourth lymph node biopsy he was diagnosed as having idiopathic plasmacytic lymphadenopathy with polyclonal hyperimmunoglobulinemia. At that time his serum IgG level was 8,090 mg/dl. The elevated serum interleukin-6 (IL-6) level, up to 21.1 pg/ml, was particularly interesting, because IL-6 is involved in the oncogenesis of plasmacytoma/myeloma. The patient also had thrombocytosis, hematuria, and a serum increased level of C reactive protein which seemed to be related to the effects of IL-6 i.e. thrombopoiesis, induction of the proliferation of mesenchymal cells, and induction of the production of acute phase proteins by hepatocytes, respectively. Even though he displayed no outward symptoms before and after treatment with prednisolone and melphalan, elevated immunoglobulin levels were still present.

[Clinical significance of serum carcinoembryonic antigen in small cell lung cancer patients]

In this study, the clinical significance of serum carcinoembryonic antigen (CEA) level in small cell lung cancer patients was investigated. The relationship between serum CEA level before treatment and the effect of chemotherapy was analyzed. In 97 evaluable patients with small cell lung cancer, the 26 who had elevated CEA values of 10.0 ng/ml or greater at diagnosis tended to be resistant to intravenous systemic chemotherapy. In patients with limited disease (LD), survival time of 13 patients whose CEA levels were 10.0 ng/ml or greater was shorter than that of the other LD patients. These findings suggest that small cell lung cancer patients with high serum CEA levels are less responsive to standard chemotherapy, and serum CEA level may be able to identify biologically different tumors from common small cell cancer.

Penetration of etoposide into human malignant brain tumors after intravenous and oral administration

Penetration of etoposide into the cerebrospinal fluid, brain tumor, and brain tissue after intravenous administration was investigated in patients presenting with malignant brain tumors. A relatively low dose (55-65 mg/m2) was used to compare intravenous with oral administration. High-performance liquid chromatography with fluorescence detection was used to evaluate drug levels. Plasma and cerebrospinal fluid levels of etoposide after oral administration (50-150 mg/day) were also studied so as to determine the adequate oral dose for the treatment of malignant brain tumors. The peak plasma concentration after intravenous administration ranged from 7.01 to 10.47 micrograms/ml, varying in proportion to the injected dose, whereas that after oral administration was lower, namely, 1.44-4.99 micrograms/ml, and was unstable when the oral dose was 150 mg daily. The peak cerebrospinal fluid level following either intravenous or oral administration was much lower than the plasma concentration and was influenced by the peak plasma level and the sampling site. The etoposide concentration in cerebrospinal fluid taken from the subarachnoid space and ventricle of patients displaying no tumor invasion and of those presenting with meningeal carcinomatosis and in cerebrospinal fluid taken from the dead space after tumor resection was 0.7% +/- 0.5%, 3.4% +/- 1.0%, and 7.2% +/- 8.5%, respectively, of the plasma concentration. Serial oral administration did not result in the accumulation of etoposide in cerebrospinal fluid. The tumor concentration (1.04-4.80 micrograms/g) was 14.0% +/- 2.9% of the plasma level after intravenous administration, was related to the injected dose, and was approximately twice the concentration detected in the brain tissue. Therefore, a relatively low dose of etoposide injected intravenously penetrates the brain tumor at an efficacious concentration. Our results indicate than an oral dose of 100 mg etoposide be given for malignant brain tumors, as limited penetration of the drug into the intracranial region was observed.

[Effects of sevoflurane anesthesia on norepinephrine metabolism in rat brain]

In spite of many investigations done for many years, the mechanism of general anesthesia remains still unclear. To elucidate the mechanism of general anesthesia, effects of sevoflurane anesthesia on norepinephrine metabolism in rat brain was studied. Sevoflurane 3% was administered for 20 minutes to Wistar male rats weighing 230-270g under spontaneous respiration. The rats were sacrificed by decapitation and the brains were rapidly removed. They were dissected into nine discrete regions, locus coeruleus, pons plus medulla oblongata, hypothalamus, thalamus, basal ganglia, hippocampus, amygdala and cerebral cortex. The contents of norepinephrine (NE) and one of its major metabolites, 3-methoxy-4-hydroxyphenyl-ethylene glycol (MHPG) were measured by high performance liquid chromatography with the dual-cell coulometric detector before anesthesia, 20 minutes after the start of anesthesia and at recovery from anesthesia. Significant increases in NE levels were observed in the pons, thalamus and hippocampus by sevoflurane anesthesia for 20 minutes compared with the control group and also in the pons and midbrain at recovery from anesthesia. MHPG levels were significantly decreased in the pons and cortex by sevoflurane anesthesia, while an appreciable increase in MHPG levels was observed in the thalamus by sevoflurane anesthesia. It is concluded that NE metabolism is significantly suppressed in the pons, thalamus and hippocampus during sevoflurane anesthesia and this change in NE metabolism may be associated with a mechanism of sevoflurane anesthesia.

Threshold dose dependence in phenobarbital promotion of rat hepatocarcinogenesis initiated by diethylnitrosamine

The dose-response of phenobarbital (PB) promotion of hepatocarcinogenesis in rats was investigated. Male F344 rats were given 1, 4, 16, 75, 300 or 1200 p.p.m. PB solutions given ad libitum as their drinking water for 39 weeks following initiation with a single i.p. injection of diethylnitrosamine (DEN) (100 mg/kg). At week 40, the incidence of hepatic tumors was increased clearly in the DEN + PB groups given 300 p.p.m. PB or above, as compared to that in the group given DEN only. Linear dose-response curves for numbers and sizes of enzyme-altered hepatic foci (gamma-glutamyl-transpeptidase or placental glutathione S-transferase positive foci) were obtained in the dose range 16-1200 p.p.m. PB. The minimum promoting dose level of PB for enzyme-altered foci, estimated from dose-response curves by the Logit model, was calculated to be 15-23 p.p.m. Thus while dose dependence was demonstrated over a large range, a threshold was evident at low doses.

[Effect of almitrine in acute canine lung injury induced by paraquat]

The effects of intravenously administered almitrine (0.3 or 1.0 micrograms/kg/min, for 30 min) on hemodynamics and pulmonary gas exchange were assessed in eight dogs with acute lung injury induced by paraquat under controlled ventilation. Arterial blood gases, pulmonary and systemic hemodynamics, and ventilation-perfusion distribution (VA/Q) using the multiple inert gas elimination technique were examined before (control) and during infusion of almitrine. Almitrine produced significant increases in mean pulmonary arterial pressure from 17.4 +/- 3.3 (control, mean +/- SD) to 20.4 +/- 1.5 mmHg (1.0 micrograms/kg/min), and in total pulmonary vascular resistance. There was no change in other hemodynamic parameters, arterial gas tensions, or VA/Q distribution. These results indicate that almitrine causes pulmonary vasoconstriction without changing ventilation-perfusion distribution in dogs with paraquat-induced lung injury.

Optic nerve head blood speed as a function of age in normal human subjects

We used the laser Doppler technique to determine the relation between age and the speed of blood cells moving through the capillaries of the optic nerve head. We studied 22 normal human volunteers ranging in age from 16-76 years. The results were best described by a statistically significant quadratic relationship between capillary blood speed and age. Blood speeds were lowest in the youngest and oldest subjects and highest in subjects between 27 and 35 years old. A two-phase linear model showed a statistically significant 20% decrease in blood speed in volunteers between the ages of 31 and 76. The results were not affected by gender, degree of refractive error, systemic blood pressure, intraocular pressure, cup/disc ratio of the optic nerve head, or by site-to-site differences in the light scattering properties of the optic nerve head tissue. Capillary blood speed was, on average, 15% greater from temporal sites than from nasal sites, corresponding to the equally greater distribution of ganglion cell axons within the same area. The results provide a baseline of normal age-controlled data that can be compared to measurements obtained from patients with disorders of the optic nerve head thought to have a vascular etiology.

[Plasma cell tumor of the parieto-occipital bone; a case report]

Plasmacytoma originating in the cranial bone is a rare disease. A report is presented of a case of plasmacytoma originating in the parieto-occipital region. The patient was a 62-year-old male with palpation of a parieto-occipital mass as chief complaint. He showed no neurological deficit. Ig-G in the serum was 2240 mg/dl, and M-protein (n-type) was demonstrated in the serum. Bence-Jones protein was negative and bone marrow was normal. Skull X-ray showed osteolytic change in the parieto-occipital region. CT scan and MRI demonstrated a markedly enhanced mass extending from the epidural to the subcutaneous space at the parieto-occipital region. Common carotid angiography showed remarkable tumor stain flowing from the occipital artery, the superficial temporal artery, and the middle meningeal artery. Following embolization of the bilateral occipital artery, parieto-occipital horse shoe scalp incision was done. The tumor was elastic soft and bled easily around the margin of destroyed bone. Subtotal removal of the tumor was accomplished. The removed surgical specimen of the tumor was found to be plasmacytoma. The patient's postoperative course was favorable and no neurological deficit was found. Laboratory studies revealed a remarkable reduction of Ig-G in the serum to 1170 mg/dl. Six months after the operation, no signs of recurrence were seen on CT scan. Plasmacytoma originating in the cranial bone is so rare that only 18 cases have been reported to date. In these cases, laboratory studies have shown no evidence of anemia, Bence-Jones protein in urine, and abnormality of the bone marrow which are characteristic of multiple myeloma.(ABSTRACT TRUNCATED AT 250 WORDS)

[Pulsatile administration of LH-RH for hypogonadotropic hypogonadism]

A case of hypothalamic-pituitary failure is reported. A 28-year-old man who had been treated with testosterone for hypogonadism for two years was admitted to our hospital with the chief complaint of sexual problems. The serum level of gonadotropins was very low and hypophysial responses to luteinizing hormone-releasing hormone (LH-RH) were good. Treatment was started with subcutaneous pulses of 10 micrograms LH-RH every 120 minutes using a portable infusion pump. Gradually, his potency improved and ejaculation returned. The serum concentration of FSH, LH and testosterone increased to the normal range of adult males and the testicular volume increased rapidly from 5 ml to 14 ml after 13 weeks of treatment. Sperms appeared in the ejaculated fluid after 25 weeks and, after following 16 weeks, the concentration of sperms increased up to 20 x 10(6)/ml. Prolonged pulsatile subcutaneous administration of a low-dose of LH-RH at a physiologic frequency was an effective therapy for pubertal induction and maturation in hypogonadotropic hypogonadism due to hypothalamic-pituitary failure.

Intraventricular hemangiopericytoma--case report

A very rare large intraventricular hemangiopericytoma occurred in a 41-year-old male with a 2-month history of headache and paresthesia of the right shoulder and arm. The tumor was partially removed, followed by 50 Gy local Linac irradiation given over 6 weeks. Four months later the residual tumor demonstrated a marked decrease in size and vascularity. The residual tumor was totally removed with less operative bleeding than at the initial operation. This is the first reported case of hemangiopericytoma located in the trigone of the lateral ventricle.

Dose-dependent enhancing effects of quinacrine on induction of preneoplastic glutathione S-transferase placental form positive liver cell foci in male F344 rats

Dose-dependent modifying effects of quinacrine on induction of preneoplastic liver cell foci were investigated in male F344 rats. Six week old animals were injected i.p. with N-nitrosodiethylamine (DEN) at a dose of 200 mg/kg, and starting 2 weeks later, rats were given quinacrine at dietary levels of 20, 100 and 500 p.p.m. for 6 weeks. Groups without either DEN or quinacrine treatment were used as controls. At week 3 following DEN administration, all animals were subjected to two-thirds partial hepatectomy, and after killing the animals at week 8, development of preneoplastic liver cell foci was investigated using the glutathione S-transferase placental form (GST-P) as a marker. The numbers and unit areas of GST-P-positive foci per cm2 were significantly increased in the DEN/quinacrine (500 p.p.m.) group as compared to DEN-alone group values. An increase in number was also evident in the 100 p.p.m. but not the 20 p.p.m. treated group, no lesions being induced by quinacrine alone (500 p.p.m.). Electron microscopic study confirmed that quinacrine dose-dependently induces lipidosis in hepatocytes, i.e. markedly myeloid lamellar cytoplasmic inclusion bodies were observed. The results thus demonstrated that quinacrine treatment enhances GST-P-positive liver cell foci development in a dose-dependent way, this effect presumably being related to the induction of lipidosis.

Oscillatory potentials and permeability of the blood-retinal barrier in noninsulin-dependent diabetic patients without retinopathy

Electroretinography and vitreous fluorophotometry were performed in 36 eyes of 36 noninsulin-dependent diabetic patients and in 32 eyes of 32 healthy control subjects between the ages of 30 and 59 years. Fluorescein fundus angiograms showed no abnormalities in either group. Peak implicit time of the first deflection of the oscillatory potential, interpeak interval between the first and second deflections, and the sum of the amplitudes of the upward deflections were analyzed. Inward permeability of the blood-retinal barrier was calculated by vitreous fluorophotometry and computer simulation. The peak implicit time of the first deflection and the interpeak interval between the first and second deflections of the oscillatory potential were significantly longer in diabetic patients than in control subjects (P less than 0.01). No significant difference in inward permeability of the blood-retinal barrier existed between the two groups. These results indicate that a selective delay in the peak implicit time of the oscillatory potential (neurosensory retinal abnormality) may be present in noninsulin-dependent diabetic patients, representing retinal functional changes before changes in blood-retinal barrier permeability are apparent.

[A case of pituitary adenoma with simultaneous secretion of TSH and GH detected by double immunostaining method]

A rare case of simultaneous hypersecretion of thyroid stimulating hormone (TSH) and growth hormone (GH) in a pituitary adenoma is reported. A 59-year-old male complaining of general fatigue, dyspnea on exertion and finger tremor was admitted. Examination on admission, he revealed with hyperthyroidism and hypersecretion of TSH and thyroid hormones. Administration of TRH did not further increase serum TSH level, and administration of T3 also had no effect on TSH secretion. CT scan showed a pituitary macroadenoma 13mm in diameter. MRI demonstrated a homogenously hypointense mass with Gd-DTPA enhancement in the left side of the sella turcica. The entire chromophobic adenoma was removed by trans-sphenoidal surgery. Immunostaining of the specimen showed that the cytoplasm of the adenoma cells was positive for both TSH and GH. Double immunostaining using avidin-biotin-peroxidase complex (ABC) method and immunogold silver staining (IGSS) method, showed that the adenoma cells had been secreting both GH and TSH at the same time. After the adenomectomy, the hyperthyroidism disappeared, and all altered indicators of pituitary function returned to normal.

[Selective enhancement of tumor blood flow and drug delivery to brain tumors in experimental rat gliomas under angiotensin II-induced hypertension]

Regional blood flow of brain tumors and normal brain tissue of rats before and during angiotensin II (AT II)-induced hypertension were measured using an electrolytic flowmeter and a laser flowmeter. Etoposide concentration in the tumor and brain tissue after intracarotid administration were also measured in brain tumor bearing rats with or without AT II-induced hypertension. A suspension of 5 x 10(5)/10 microliters 9L gliosarcoma cells was inoculated into the left caudate-putamen of CD Fischer 344 rats. Before induced hypertension, regional blood flow of the tumor (28.2 +/- 2.6 ml/100 g/min; mean +/- SEM) and the contralateral caudate-putamen (23.0 +/- 1.8 ml/100g/min) in the tumor bearing rats were significantly lower than that of the caudate-putamen (43.9 +/- 4.1 ml/100g/min) in the normal rats (p less than 0.01). Intravenous administration of AT II at a dose of 0.4-0.6 microgram/body/min increased the mean arterial blood pressure from 96.5 +/- 4.7 mmHg to 138.0 +/- 3.6 mmHg. AT II-induced hypertension resulted in an approximate 1.8(1.1 - 3.6)-fold increase in the regional tumor blood flow. On the other hand the regional blood flow of the contralateral caudate-putamen was slightly decreased at the rate of 6%. The mean concentration of etoposide with AT II-induced hypertension in the tumor tissue was 2.2-fold higher than that without AT II-induced hypertension. However, etoposide delivery to normal brain tissue was small. From these results, induced hypertension with intravenously administrated AT II selectively increase the tumor blood flow and drug delivery to brain tumor tissue. Intracarotid chemotherapy with AT II-induced hypertension might contribute to enhance therapeutic effect of malignant brain tumors.

Outcome of primary central nervous system lymphoma--a study of 32 patients

The outcomes in 32 cases of histologically diagnosed primary central nervous system lymphoma were investigated. The 1-, 2-, and 5-year survival rates were 54, 36, and 8%, respectively. Good outcome was indicated by extensive surgical removal with 50-Gy irradiation and lower ages. 61% of patients receiving radiation therapy suffered recurrence within 1 year. The incidence of multiple lesions increased at recurrence. These lesions were almost all remote from the initial site in the brain, occurring more frequently in the central part of the supratentorial regions near the ventricle. Multiple lesions recurred more rapidly than single lesions. Longer survival times were indicated by a long tumor-free period after initial treatment. Extensive surgical removal results in long survival times for patients with a localized single tumor in the early stage. Radiochemotherapy should be given as part of the initial treatment.

Effect of timolol on human retinal, choroidal and optic nerve head circulation

In a double-masked, randomized, placebo-controlled study, we evaluated the effect of topical timolol maleate 0.5% on the retinal, choroidal, and optic nerve head circulation in 5 healthy volunteer subjects. Changes in the pulsatile component of choroidal blood flow (PCBF) were determined from measurements of the ocular pulse wave. Changes in the retinal arterial blood flow rate (RBF) and optic nerve head capillary blood speed (CBS) were determined by laser Doppler velocimetry and monochromatic photography. In timolol-treated eyes, PCBF decreased by 32 +/- 12% (p = 0.0007). Changes in RBF and CBS were not statistically significant. In the contralateral placebo-treated eyes, PCBF decreased by 15 +/- 8% (p = 0.006) and RBF increased by 18 +/- 10% (p = 0.002). The change in CBS was not statistically significant.