Low-silver amalgam restorations: a two-year clinical evaluation

A clinical survey of amalgam restorations made with four proprietary alloys with low-silver and high-copper contents was followed during a two-year period, according to USPHS criteria. With the exception of one alloy, the marginal integrity was found to be very satisfactory. All the restorations lost their superficial luster in a short period of time.     

Dopamine might not be involved in the pathogenesis of polycystic ovary syndrome

The possible alteration in dopamine (DA) metabolism as an etiological factor was investigated in 31 normoprolactinemic patients with typical polycystic ovary syndrome (PCOS) in comparison with 14 normal women (early follicular phase). Subjects were submitted to intravenous infusion of 4 micrograms/kg DA per minute over a period of 3 hours and blood samples were collected every 30 minutes over a period of 5 hours. Two days later subjects were submitted to intravenous infusion of 10 mg metoclopramide (MCP) as a bolus and blood samples were collected every 15 minutes over a period of 2 hours. Dopamine infusion caused a similar maximum decrease (MD) in LH levels in both the PCOS and control groups (50.9% and 47.5%, respectively). No changes in plasma LH levels were observed in either group after MCP infusion. Dopamine caused a 50.2% and 60.4% MD in prolactin (PRL) in the PCOS and control groups, respectively, the difference being statistically non-significant. Metoclopramide increased PRL levels by 1261.0% and 1832.0% in the PCOS and control groups, respectively (not significant). In a double-blind study, the PCOS patients were treated with 5 mg/day bromocriptine (n = 16) or placebo (n = 15) over a period of 3 months and evaluated in clinical and laboratory terms during and after treatment. Seven patients in each group had monthly menstrual periods, but only 1 in each group had an ovulatory cycle (progesterone greater than 5 ng/ml). During treatment, median plasma PRL levels were significantly decreased only in bromocriptine-treated patients (10.8 vs 7.3 ng/ml). The present results lead us to question whether dopamine is indeed involved in the pathogenesis of normoprolactinemic PCOS and whether bromocriptine treatment is of benefit in this type of patients.     

Microinjection of metallothionein-oncomodulin DNA into fertilized mouse embryos is correlated with fetal lethality

Oncomodulin (ONCO) is an oncodevelopmental protein expressed in placental and extraembryonic tissue and re-expressed in a wide variety of tumors. The metallothionein promoter (MT) is active in numerous adult tissues, in parietal and visceral extraembryonic endoderm, and developing liver. To study the function of oncomodulin we microinjected MT-ONCO DNA into one-cell embryos and examined tissues of fetal and adult mice. Analysis of implant sites from embryos, microinjected with MT-ONCO DNA then placed into pseudopregnant females, indicated a greater than three-fold increase in empty and necrotic implant sites relative to SV2NEO-microinjected embryos and a seven-fold rise relative to non-microinjected embryos. The striking feature of the lethality was the presence of a normal placenta but absence of fetal tissue. Few MT-ONCO DNA transgenic mice were isolated (3.5%) and none were able to express oncomodulin protein or RNA in any tissue examined, even after prolonged heavy metal stimulation of the MT promoter. Fetal mortality is best correlated with expression of oncomodulin causing an interruption of either cellular differentiation or organogenesis before day 9 in development.     

Tumefactive extramedullary hematopoiesis of the stomach.

A 3 X 4 cm submucosal gastric mass of extramedullary hematopoeitic tissue occurred in a patient with chronic myelogenous leukemia. Such stomach masses have been misinterpreted as malignant tumor. Tumefactive extramedullary hematopoiesis of the stomach is an infrequent occurrence in patients with extramedullary hematopoiesis but should be considered in the differential diagnosis of patients known to have this condition.