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T J Madden

Publications and source records attributed to T J Madden.

4 recordsLinked to original sources
PubMed1999

Leginon: a system for fully automated acquisition of 1000 electron micrographs a day.

We have developed a system to automatically acquire large numbers of acceptable quality images from specimens of negatively stained catalase, a biological protein which forms crystals. In this paper we will describe the details of the system architecture and analyze the performance of the system as compared to a human operator. The ultimate goal of the system if to automate the process of acquiring cryo-electron micrographs.

Automation↗
PubMed1999

Intraocular carboplatin concentrations following intravenous administration for human intraocular retinoblastoma.

Previous studies of the penetration of carboplatin into the vitreous have depended on unaffected animals or on animal models for other cancers. The objective of this study was to determine the intraocular levels of carboplatin following intravenous administration of carboplatin in the treatment of human intraocular retinoblastoma. Eight patients with bilateral intraocular retinoblastoma were treated in a consistent fashion with intravenous carboplatin. One additional patient was similarly treated, but enucleated one month later. Samples were taken from those nine eyes after enucleation one to two hours after the administration of 18.7 mg/kg (560 mg/m( 2) for patients more than 12 kg) of intravenous carboplatin, and carboplatin concentrations in the aqueous and vitreous were then measured by atomic absorption spectrometry. The mean concentration measured in the aqueous was 5.13 microg/ml and in the vitreous 4.05 microg/ml, and vitreal concentrations were an average of 80% of aqueous concentrations. In one patient, a vitreous concentration of carboplatin was detected after an interval of one month that was 10% of the levels found in the samples enucleated one hour post-administration. These concentrations are much higher than previous animal studies would predict, and are similar to levels measured in unaffected animals when the drug is given after the use of cryotherapy. The concentration also approaches levels previously shown to be toxic to the retina. This elevation in carboplatin concentration may be due to disruption of the blood-vitreous barrier by active tumor.

Antineoplastic Agents↗
PubMed1977

Endometrial screening of asymptomatic women by irrigation technique in the private gynecology office.

A study was made of 201 asymptomatic women over age 40 (range, 40-74 years) who underwent uterine sounding and endometrial screening by the negative-pressure jet irrigation technique, without anesthesia, in private gynecologists' offices. Introduction of the irrigator was accomplished in 88 percent of these patients. In 97 percent of the successful irrigations, the specimens obtained were satisfactory for cytologic and histologic diagnosis of neoplasia. No occult endometrial carcinomas were discovered. The factors which interfered with endometrial screening by these methods are analyzed. Cervical stenosis prevented endometrial irrigation in 13 of the 24 unsuccessful attempts. Acceptance by the patients was high, in that 74.2 percent reported slight or no discomfort and only 4.7 percent complained of severe discomfort. Although 12.5 percent experienced pelvic cramping after irrigation, no other significant side effects were observed. The results of this investigation indicate the feasibility of using the endometrial irrigation technique for massive screening studies of asymptomatic women who are at risk for the development of endometrial carcinoma.

Adult↗