In the matured chick retina, alkaline phosphatase (ALPase) activity is specifically localized in the outer plexiform layer and in horizontal and Müller cells. In the developing chick retina, ALPase activity is first recognized in growing neurites from horizontal cells during the 13th day of incubation, when synaptogenesis begins in the outer plexiform layer. Intraocular administration of ALPase inhibitors to developing chick embryos resulted in developmental disturbances in differentiation of the outer plexiform layer and also of photoreceptor cells. We have now extended these studies to an in vitro system. ALPase activity was studied by ultracytochemistry in cultured retinal cells from chick embryos, and the effects of specific ALPase inhibitor on retinal development were also analyzed. Two cell types showed intense ALPase activity: 1) flat glial cell, which formed a multi-layered epithelial sheet and 2) neuronal cell found within cell aggregates. Some cellular processes forming a neuropil-like structure within these aggregates also showed ALPase activity. When the ALPase inhibitor bromotetramisole was present in the culture medium, there was delay in aggregate formation and the development of neuritic processes was also affected. Moreover, this treatment also caused a considerable reduction in the number of photoreceptor cells present in the culture. The present results indicate that ALPase activity plays a significant role in retinal cell differentiation.

Alkaline Phosphatase↗

PubMedDate not supplied

A study of unilateral brief focal atonia in childhood partial epilepsy.

We studied unilateral brief focal atonia (BFA) in seven patients with childhood partial epilepsy. BFA was observed as a transient dropping of one arm lasting from 100 to 150 ms when patients were asked to keep both arms outstretched in front of the body. Close examination using simultaneous video-polygraphic recordings showed dropping of the arm to correspond exactly with a single sharp and slow wave complex arising from the contralateral centrotemporoparietal region. The BFA occasionally would progress to atonic seizures or atonic absence seizures, when the localized epileptic discharge evolved into generalized discharges. In one patient we found a positive correlation between the intensity of BFA and the amplitude of the contralateral epileptic discharges. A higher amplitude corresponded to more pronounced BFA and a lower amplitude to less pronounced BFA. These results led us to conclude that the apparently interictal single sharp and slow wave complex in the rolandic region may inhibit contralateral motor control, thus producing BFA that corresponds with the spike amplitude.

Brain↗

PubMedDate not supplied

Effect of dietary magnesium on development of atherosclerosis in cholesterol-fed rabbits.

The effect of dietary magnesium (Mg) on the development of atherosclerosis in cholesterol-fed rabbits was investigated. Male New Zealand White rabbits (n = 31) were placed on five kinds of diets: regular, 1% cholesterol, and 1% cholesterol diets supplemented with either 300, 600, or 900 mg (as Mg) of Mg sulfate. The regular and 1% cholesterol diets contained 400 mg of Mg per 100 g. Each rabbit received 100 g daily of the appropriate diet. Additional Mg was well tolerated and did not affect blood pressure or body weight. The rabbits were sacrificed after 10 weeks, and the oil red O-positive atherosclerotic area that covered the aortic intima and the cholesterol content of the aorta was measured. Additional Mg decreased both the area of the aortic lesions and the cholesterol content of the aortas in a dose-dependent manner. The 1% cholesterol diet significantly increased plasma cholesterol and triglyceride concentrations and decreased high density lipoprotein (HDL) cholesterol concentration. Additional Mg had no further effect on cholesterol and HDL cholesterol concentrations, but it slightly decreased the rise in triglyceride concentration. These results indicate that dietary Mg prevents the development of atherosclerosis in cholesterol-fed rabbits by inhibiting lipid accumulation in the aortic wall.

Animals↗

PubMedDate not supplied

Lobar intracerebral hemorrhage: etiology and a long-term follow-up study of 32 patients.

Thirty-two patients with lobar hematoma were encountered during a period of six and a half years. Of these patients, 13 had arterial hypertension, 7 had other etiologies, and the remaining 12 were without apparent etiology. In 5 of these patients, cryptic angiomas were suspected from angiograms and CT scans. In one young patient, there was a later recurrence of hemorrhage that resulted in death. Our experience in this series and a review of the literature have led us to conclude that, in young normotensive patients with lobar hematoma, surgical intervention may be a reasonable consideration so that evacuation of the hematoma may be accomplished and a detailed search for small angiomatous malformations may be carried out with a view to preventing recurrences.

Adolescent↗

PubMedDate not supplied

A simple mathematical model for life-shortening by radiation.

Explore the source record for details and available documents.

Mathematics↗

PubMedDate not supplied

Substance P nerve fibres in the canine larynx by PAP immunohistochemistry.

The distribution of the Substance P (SP) immunoreactive nerve fibres in the canine larynx and laryngeal nerves was studied by PAP immunohistochemistry. Many individual SP immunoreactive nerve fibres with varicosities were observed within the epithelial layer and in the connective tissue below the epithelium of the laryngeal mucosa. Small numbers of SP immunoreactive nerve fibres were also found in the submucosal gland region and some of them appeared to terminate in glandular cells. These findings are consistent with the view that SP might be involved in the laryngeal sensory innervation system and the laryngeal glandular secretion. No SP immunoreactive nerve fibres were found in any intrinsic laryngeal muscles. The recurrent laryngeal nerve and the superior laryngeal nerve contained SP immunoreactive nerve fibres and were considered to lie in the pathway of the SP nerve fibres to the larynx.

Animals↗

PubMedDate not supplied

Fertility and uterine size among Asian women undergoing hysterectomy for leiomyomas.

OBJECTIVE: To ascertain whether an epidemiological relationship exists between fertility and uterine leiomyomas, and whether uterine size is associated with fertility among Asian women undergoing hysterectomy for leiomyomas. METHODS: The study was conducted in Sapporo, Japan. 91 women undergoing hysterectomy for myomas were compared with age-matched controls with respect to reproductive factors. Further comparisons were made of these factors in women with large myomas and those with small ones. RESULTS: Women with leiomyomas were more likely to be nulliparous than controls (P < .01), and the risk of leiomyoma increased as the number of births decreased (P < .01). Time since last birth was associated with increased risk in women with large myomas (P < .05). Women with fewer births undergoing hysterectomy for leiomyomas tended to have greater uterine weight. CONCLUSION: Fewer births may be a cause of larger leiomyomas.

Adult↗

PubMedDate not supplied

Progression of esophageal carcinoma by loss of EGF-STAT1 pathway.

PURPOSE: In only a very limited number of cultured cell lines, epidermal growth factor (EGF), a potent mitogen for many kinds of cells, was shown to activate STAT1 (signal transducer and activator of transcription 1) protein, which can transmit signals that cause cell growth arrest and apoptosis. The purpose of this work is to elucidate the physiologic and/or pathological significance of this EGF-STAT1 pathway. MATERIALS AND METHODS: A series of cultured cell lines that had been established from surgical specimens of esophageal squamous cell carcinoma was studied for the existence of the EGF-STAT1 pathway. Normal esophageal squamous epithelial cells either explanted from non-neoplastic portions of surgically removed human esophageal tissue or in bovine esophageal epithelium in situ were examined as well. RESULTS: EGF treatment leads to a strong growth arrest in three of the 30 esophageal squamous cell carcinoma cell lines. STAT1 was found to be activated by EGF in the three cell lines but not in the others. EGF can also activate STAT1 in cultured normal esophageal squamous epithelial cells. STAT1 is at the activated state in the basal cell layer of the bovine esophageal epithelium. Notably, patients who had harbored the cancer cells with the EGF-STAT1 pathway had a dramatically better prognosis. DISCUSSION: The EGF-STAT1 pathway may be intrinsic to esophageal epithelial lineage of cells and is lost in a considerable fraction of the carcinomas. This loss appears to cause a significantly more malignant clinical course. These findings may point out a critical step in the progression of esophageal cancer and could lead to the development of useful clinical applications.

Blotting, Northern↗

PubMedDate not supplied

Cytotoxicity of smancs in comparison with other anticancer agents against various cells in culture.

The cytoxicity of neocarzinostatin (NCS) and smancs [copoly(styrene maleic acid)-conjugated NCS] to various cultured cells was compared with that of several other antitumor agens in clinical use on various malignant and non-malignant cells as regards to their effect on colony formation of cells. Both NCS and smancs showed the most potent cytotoxicity against all tumor cell lines tested; the IC50s (colony inhibitory concentration 50%) of these drugs were 3.2-20 nM, 10-1000 times lower than those of other drugs. In contrast, NCS and smancs exhibited relatively lower toxicity to normal cells such as human skin fibroblasts and chick embryonic fibroblasts (IC50, about 50 and 100 nM, respectively). Normal rat hepatocytes were found to be very resistant to NCS and smancs (both IC50s were about 500 nM). Moreover, the minimum exposure time of smancs to cultured tumor cells required to achieve effective cytotoxic activity was much shorter than that of NCS and other drugs. Namely, at 30 nM more than 80% cells were killed by exposure to smancs for only a few minutes, whereas with NCS more than 80 min of exposure time was required. It was also found that smancs inhibited the uptake of 3H-thymidine into DNA as expected. These results clearly indicate that smancs is an unique antitumor agent with a broad antitumor spectrum which exhibits some characteristics similar to, but also some very different from NCS.

Animals↗

PubMedDate not supplied

Germ cell tumors (germinoma and yolk sac tumor) in unusual sites in the brain.

This report presents three cases of primary intracranial germ cell tumor encountered in unusual sites, or essentially non-midline structures. The three provided the opportunity to examine surgically obtained tissues with the electron microscope. The histological diagnosis was initially made by light microscopic observations. The first case was a 10-year-old boy in whom the tumor occupied the right thalamic and basal ganglionic region and was diagnosed as a yolk sac tumor. The second an 11-year-old boy who presented with a mass lesion on the left thalamic and basal ganglionic region, diagnosed as germinoma. The third was a 39-year-old man who presented with multiple tumors in the ventricular system and posterior fossa, also diagnosed as germinoma. Among the three cases, neither diabetes insipidus nor ophthalmologic disorder was manifested. Extensive examination and autopsy findings indicated that these intracranial lesions had not metastasized from primary extracranial tumors, including those of the genital organs.

Adult↗