Local carboplatin therapy in transgenic murine retinoblastoma

PURPOSE

To determine the efficacy and toxicity associated with intraocular delivery of carboplatin in the treatment of murine transgenic hereditary retinoblastoma.

METHODS

Forty-eight transgenic BLH-SV40 Tag retinoblastoma mice were administered five intravitreal injections of carboplatin in one eye. After 12 weeks, the eyes were examined histopathologically to evaluate tumor burden. Twelve rabbits were administered intravitreal injections of carboplatin in one eye, after which they underwent serial electroretinography. All experimental and control eyes were obtained for histopathology and electron microscopy.

RESULTS

A dose-dependent inhibition of intraocular tumor growth by carboplatin was observed in transgenic retinoblastoma mice. Tumor development was inhibited in 50% of the mouse eyes at doses of 1.4 micrograms. In rabbits, retinal toxicity resulted when intravitreal injections of carboplatin were administered at doses of 10 micrograms or higher.

CONCLUSIONS

Local delivery of carboplatin in serial doses effectively inhibits intraocular tumor growth in a dose-dependent manner in transgenic murine retinoblastoma.

The genetics of retinoblastoma and current diagnostic testing

We review the genetics of retinoblastoma and the most recent molecular detection methods. Retinoblastoma, the most common intraocular tumor in children, occurs in either a heritable or non-heritable form. The heritable form, which is highly penetrant and predisposes individuals to a considerably greater second tumor risk, can be distinguished most definitively through the use of genetic testing. Genetic testing for individuals and families suspected of carrying the heritable mutations can help ensure that more comprehensive treatment plans and accurate genetic counseling for affected individuals and their families are provided.

Developing and implementing a self-learning packet on epidural analgesia

Epidural analgesia offers a highly effective route of providing acute pain relief. As this mode of medication delivery is used more frequently in the acute care setting, nurses must acquire theoretical knowledge, apply monitoring parameters, and demonstrate technical competency. Implementing a self-learning packet to educate nursing staff caring for patients receiving epidural analgesia is an effective teaching medium and can help improve clinical performance.

Efficacy of outpatient induction with low-dose intravaginal prostaglandin E2: a randomized, double-blind, placebo-controlled trial

OBJECTIVE

Our purpose was to determine whether a protocol for outpatient induction is safe and effective for initiating labor.

STUDY DESIGN

A randomized, double-blind, placebo-controlled trial was performed with 100 low-risk patients having well-dated pregnancies. Women with a Bishop score < or = 6 at 38 to 40 weeks' gestation were administered either 2 mg of intravaginal prostaglandin E2 gel or placebo for 5 consecutive days as outpatients while undergoing fetal monitoring.

RESULTS

The median interval from randomization to delivery was 4 days in the prostaglandin E2 group (range 0 to 28 days) versus 10 days in the placebo group (range 0 to 26 days, p = 0.002). Twenty-seven of 50 patients (54%) in the prostaglandin E2 group were admitted for labor during the dosing interval compared with 10 placebo-treated patients (20%, p = 0.001). The mean gestational age at delivery was significantly reduced in the treatment group (39.9 +/- 1.0 weeks vs 40.5 +/- 0.99 weeks, p = 0.003) as was the incidence of postdates pregnancy (40% vs 66%, p = 0.016). Hyperstimulation was observed in one prostaglandin E2-treated patient, but no intervention was required.

CONCLUSIONS

Outpatient low-dose prostaglandin E2 gel administration is effective for initiating labor in patients with an unfavorable cervix and appears safe if performed with adequate monitoring.

Comparison of tape products on skin integrity

A two-group, nonconcurrent design was used in this comparative study to assess the incidence of skin breakdown accompanying Durapore silk tape and Medipore soft cloth tape (both manufactured by 3M Health Care). A significantly higher number of skin tears were found with silk tape use (mean 2 = 7.69, p < 0.01). This type of skin damage caused patient discomfort and incurred additional treatment costs. Soft cloth tape is recommended to decrease skin tears in surgical patients.

The impact of initiating a human immunodeficiency virus screening program in an urban obstetric population

OBJECTIVE

Our purpose was to describe the incidence of human immunodeficiency virus infection and to assess the cost/benefit ratio of universal antenatal human immunodeficiency virus screening.

STUDY DESIGN

Medical records of women in this urban obstetrics population, from the years 1988 to 1993, were examined. The incidence of known human immunodeficiency virus seropositivity at delivery was determined. The costs of performing human immunodeficiency virus screening, evaluating the disease status, and administering therapy were calculated. These costs were compared with an averaged cost for care and follow-up of infants infected through vertical transmission.

RESULTS

The incidence of known human immunodeficiency virus seropositivity at delivery approximately doubled since the initiation of a human immunodeficiency virus screening program (0.26% to 0.48%). Obstetric screening added an approximate $100,000 to medical costs. The calculated cost of pediatric follow-up of human immunodeficiency virus-seropositive infants for the first 18 months was estimated at $344,355. In our population, with universal screening and zidovudine therapy, the medical costs could be reduced by $175,500 per year.

CONCLUSION

A program of voluntary human immunodeficiency virus screening increases the incidence of known human immunodeficiency virus infection. Offering screening and follow-up to all pregnant patients in an urban setting is both cost-effective and medically beneficial.

Infections, inflammations, and immune-mediated orbital disease

In recent months, many authors have described distinct surgical approaches to orbital decompression in thyroid ophthalmopathy. Comparison of outcomes data should allow the surgeon to decide on the best approach to orbital decompression in an individual patient. Patients with thyroid-associated lid retraction may also benefit from approaches that allow for postoperative suture adjustment, because alignment of the lids can be particularly challenging in these patients. The clinical evaluation of patients with thyroid disease has evolved with the recognition that magnetic resonance T2 relaxation time prolongation may correlate with an inflammatory disease phase and, perhaps, with improved response to medical management. Medical management of orbital inflammation and infection should be tailored to the specific disease process and, in many cases of infection, to the age of the patient.

Early versus late amniotomy for labor induction: a randomized trial

OBJECTIVE

Our purpose was to determine the impact of early and late amniotomy on labor induction with continuous oxytocin infusion at term.

STUDY DESIGN

A total of 209 women admitted for labor induction were randomized to early or late amniotomy. The early amniotomy group (n = 106) had membranes ruptured as soon as it was deemed safe and feasible. The late amniotomy group (n = 103) had membrane rupture performed at > or = 5 cm dilatation. The first 103 women received a continuous oxytocin infusion with incremental adjustments at 60-minute intervals as required. The next 106 women had adjustments every 30 minutes as required. Statistical analysis was confined to concurrent groups.

RESULTS

Early amniotomy was associated with shorter labor (13.3 vs 17.8 hours, p = 0.001), chorioamnionitis (22.6% vs 6.8%, p = 0.002), and significant fetal umbilical cord compression (12.3% vs 2.9%, p = 0.017). The benefit regarding shortening of labor was limited to women having oxytocin increments every 30 minutes as required (13.3 vs 17.8 hours, p = 0.001). Alternatively, the increase in chorioamnionitis was confined to the 60-minute group (39% vs 11%, p < 0.001), which also demonstrated a trend toward increased moderate and severe variable decelerations (19.6% vs 6.4%, p = 0.08).

CONCLUSIONS

When a protocol of 60-minute increments in oxytocin infusion rate is desired, amniotomy should be performed late in labor to reduce chorioamnionitis and significant umbilical cord compression. Alternatively, if early amniotomy is necessary, oxytocin should be adjusted every 30 minutes as tolerated.

Daily antenatal testing in women with severe preeclampsia

OBJECTIVE

Our purpose was to determine whether daily antenatal testing in the expectant management of severe preeclampsia remote from term prevents stillbirth or neonatal compromise at birth.

STUDY DESIGN

We reviewed the medical records of 68 women with severe preeclampsia remote from term who underwent expectant management with daily fetal testing until delivery. On admission each patient had reassuring nonstress testing (absence of persistent severe variable or late decelerations), biophysical profile (> or = 6), and amniotic fluid volume (> or = 2 cm maximal vertical pocket before 32 weeks or amniotic fluid index > or = 5 after 32 weeks).

RESULTS

There were no stillbirths. Twenty-one patients (31%) had nonreassuring testing necessitating delivery. Two neonatal deaths occurred as a result of complications of prematurity. There were no statistical differences in the cord arterial pH (p = 0.93) or in the 1- and 5-minute Apgar scores (p = 0.18 and p = 0.88, respectively) between those with normal and abnormal antenatal testing.

CONCLUSIONS

Because optimizing neonatal outcome is the only reason to prolong pregnancy in women with severe preeclampsia, confirmation of fetal well-being is mandatory. Because neither stillbirths nor fetal compromise at birth occurred in patients undergoing daily antenatal testing, we recommend daily testing in patients with severe preeclampsia managed expectantly.

Efficacy of unanesthetized spiral computed tomography scanning in initial evaluation of childhood leukocoria

PURPOSE

To evaluate the use of spiral/helical computed tomography (CT) in the preoperative evaluation of pediatric leukocoria.

METHODS

A total of 34 patient charts and imaging studies were reviewed from a consecutive series of children referred with the diagnosis of presumed retinoblastoma. Of these patients, 31 had a confirmed diagnosis of retinoblastoma. Three patients had simulating lesions, including one patient with persistent hyperplastic primary vitreous and two with Coats disease.

RESULTS

In all patients, a diagnosis of intraocular retinoblastoma could be established or excluded at the same clinical level by spiral CT as by conventional CT. Spiral CT of the eye, orbit, and midline structures was performed without a requirement for patient anesthesia. This technique resulted in a reduced volume of contrast material required for evaluation of the central nervous system and a small decrease in total radiation exposure. There was an attendant reduction in the amount of monitoring equipment required and the necessity for attending anesthesia staff.

CONCLUSIONS

The primary advantage of spiral CT is reduced anesthesia risk in small children. In addition, this technique provides necessary clinical information with a reduction in image acquisition time, monitoring equipment, and monitoring staff.

The use of a modified vaginal pouch for the diagnosis and management of premature rupture of the membranes

A modified Reality vaginal pouch (Wisconsin Pharmacal, Jackson, Wis.) was effective in assessing membrane integrity in patients evaluated for suspected premature rupture of the membranes and was useful for collecting fluid in patients requiring pulmonary maturity studies. This technique does not alter the incidence of infection and is beneficial in the management of selected patients.

Taxol and colchicine increase LPS-induced pro-IL-1 beta production, but do not increase IL-1 beta secretion. A role for microtubules in the regulation of IL-1 beta production

IL-1 beta is a proinflammatory cytokine secreted chiefly by monocytes and macrophages. Currently, much of its mechanism of processing and secretion is poorly understood, but there is increasing evidence that the microtubule system may be involved. For example, it is known that taxol and colchicine, two drugs that affect microtubule structure and function, increase LPS-induced IL-1 beta release. However, it is not known whether these drugs affect the synthesis of the 31-kDa precursor (pro-IL-1 beta) or the processing and release of mature IL-1 beta. To test this, an assay was used that allowed for the temporal separation of IL-1 beta synthesis and release. The addition of taxol or colchicine to the secretory phase of the assay resulted in no significant change in IL-1 beta release. However, when these drugs were added to the stimulus for IL-1 beta production, there was a significant increase in both IL-1 beta release and total IL-1 beta production, as measured by ELISA. These findings indicate that taxol and colchicine increase LPS-induced IL-1 beta release by an increase in the production of the precursor molecule. Thus, it is unlikely that microtubules are involved in the IL-1 beta secretory machinery in any significant manner, but they do play a role in the regulation of pro-IL-1 beta production.

Taxol and colchicine increase LPS-induced pro-IL-1 beta production, but do not increase IL-1 beta secretion. A role for microtubules in the regulation of IL-1 beta production

IL-1 beta is a proinflammatory cytokine secreted chiefly by monocytes and macrophages. Currently, much of its mechanism of processing and secretion is poorly understood, but there is increasing evidence that the microtubule system may be involved. For example, it is known that taxol and colchicine, two drugs that affect microtubule structure and function, increase LPS-induced IL-1 beta release. However, it is not known whether these drugs affect the synthesis of the 31-kDa precursor (pro-IL-1 beta) or the processing and release of mature IL-1 beta. To test this, an assay was used that allowed for the temporal separation of IL-1 beta synthesis and release. The addition of taxol or colchicine to the secretory phase of the assay resulted in no significant change in IL-1 beta release. However, when these drugs were added to the stimulus for IL-1 beta production, there was a significant increase in both IL-1 beta release and total IL-1 beta production, as measured by ELISA. These findings indicate that taxol and colchicine increase LPS-induced IL-1 beta release by an increase in the production of the precursor molecule. Thus, it is unlikely that microtubules are involved in the IL-1 beta secretory machinery in any significant manner, but they do play a role in the regulation of pro-IL-1 beta production.

Common skin problems of infancy, childhood, and adolescence

Common dermatological problems as a frequent presenting complaint are stratified by infancy, childhood, and adolescence. The common manifestations and questions asked by parents are discussed. Both infectious and noninfectious rashes are included. Convenient treatment modalities are listed.

Cell cycling and prognosis in uveal melanoma

Uveal melanoma cell cycling, quantified by bromodeoxyuridine (BrdUrd)-labeling index and mitotic index, is predictive of tumor-related mortality. Serial sections from 36 formalin-fixed melanoma specimens were labeled with BrdUrd and stained with hematoxylin and eosin. All tumors were assessed for the area of highest cell cycling activity and counts for mitotic figures and BrdUrd labeling were performed in these areas in a masked manner. The BrdUrd labeling index and mitotic index were calculated and analyzed in relation to tumor-related mortality and histopathological criteria (largest tumor diameter, cell type, extra-scleral extension, ocular location). Cox multivariate analysis estimated an increased relative risk of tumor-related mortality of 2. 32 (95% confidence interval, 1.22-4.41) per doubling of BrdUrd labeling index and 2.41 (95% confidence interval, 1.29-4.49) per doubling mitotic index. Larger tumors, nonspindle cell tumors, and anterior-located tumors tended to have higher cycling rates.

Thyroid ophthalmopathy

Thyroid ophthalmopathy, idiopathic orbital inflammation, and orbital infection can occasionally demonstrate overlapping clinical features. It is essential to distinguish between these processes because appropriate treatments are distinct in each case. In the past year, the pathophysiology of thyroid ophthalmopathy has been the topic of many reports. Orbital inflammation, particularly the fibrotic form, has been recognized to represent a distinct disease entity that may require more specifically directed treatment. In some cases cytotoxic therapies may be indicated. Orbital infection, particularly in the setting of orbital abscess, may be treated conservatively with antibiotic therapy and observation or more aggressively with surgical drainage procedures. In several recent studies, appropriate management of such infectious processes appears to be related to patient age, as well as to the specific clinical pattern of presentation.

Cervicovaginal prolactin: a marker for spontaneous preterm delivery

OBJECTIVE

Our purpose was to determine whether the presence of prolactin in cervicovaginal washings is associated with preterm birth.

STUDY DESIGN

A cohort of 80 patients underwent a washing of the ectocervix and vaginal fornices with a normal saline solution. The cohort consisted of two groups: 40 inpatients requiring tocolysis and 40 asymptomatic outpatients. The saline solution aspirates were centrifuged, the supernatant was stored at -70 degrees C, and a radioimmunoassay for prolactin was run in batch fashion. A prolactin concentration greater than the detection limit of the assay was considered a positive test result.

RESULTS

Prolactin was identified in significantly more symptomatic patients than asymptomatic controls (50% vs 5%, p < 0.0001). In symptomatic patients cervicovaginal prolactin had an 80% positive predictive value and a 65% negative predictive value for delivery at < or = 34 weeks' gestation. Patients testing positive for prolactin had significantly shorter latency from testing to delivery (16 +/- 17 vs 34 +/- 24 days, p = 0.02) and had significantly lower birth weights (1985 +/- 729 vs 2583 +/- 696 gm, p = 0.01) compared with patients testing negative. Prolactin was also identified in two asymptomatic patients, both of whom were delivered before term.

CONCLUSIONS

Cervicovaginal prolactin is a biochemical marker for preterm delivery, a shorter latency period to delivery, and lower birth weight in symptomatic patients. This test may also prove to be a valuable marker for preterm birth in asymptomatic women.

Comparative genomic hybridization in the detection of DNA copy number abnormalities in uveal melanoma

Genomic instability appears to play an important role in the development, growth, invasiveness, and eventual metastasis of the neoplastic cell. We have used a powerful new technique, comparative genomic hybridization, to evaluate genetic alterations in 10 fresh frozen uveal melanomas. Comparative genomic hybridization utilizes dual fluorescence in situ hybridization to characterize chromosome deletions and duplications, allowing for simultaneous evaluation of the entire human genome. Several consistent chromosomal abnormalities were detected. This study confirmed previous findings obtained using standard cytogenetic techniques but demonstrated an increased incidence in abnormalities of chromosomes 3 and 8; there was loss of chromosome 3 and duplication of 8q. In addition, we identified, although less frequently, other recurrent abnormal regions including alterations on chromosomes 6p, 7q, 9p, and 13q.

Subcellular localization of Cdc42p, a Saccharomyces cerevisiae GTP-binding protein involved in the control of cell polarity

The Saccharomyces cerevisiae Cdc42 protein, a member of the Ras superfamily of low-molecular-weight GTP-binding proteins, is involved in the control of cell polarity during the yeast cell cycle. This protein has a consensus sequence (CAAX) for geranylgeranyl modification and is likely to be associated, at least in part, with cell membranes. Using cell fractionation and immunolocalization techniques, we have investigated the subcellular localization of Cdc42p. Cdc42p was found in both soluble and particulate pools, and neither its abundance nor its distribution varied through the cell cycle. The particulate form of Cdc42p could be solubilized with detergents but not with NaCl or urea, suggesting that it is tightly associated with membranes. An increase in soluble Cdc42p was observed in a geranylgeranyltransferase mutant strain (cdc43-2ts) grown at the restrictive temperature. In addition, Cdc42p from a cdc42C188S mutant strain (that has an alteration at the prenylation consensus site) was almost exclusively in the soluble fraction, suggesting that membrane localization is dependent on geranylgeranyl modification at Cys-188. Immunofluorescence and immunoelectron microscopy experiments demonstrated that Cdc42p localizes to the plasma membrane in the vicinity of secretory vesicles that were found at the site of bud emergence, at the tips and sides of enlarging buds, and within mating projections (shmoo tips) in alpha-factor-arrested cells. These results indicate that Cdc42p is localized to the bud site early in the cell cycle and suggest that this localization is critical for the selection of the proper site for bud emergence and for polarized cell growth.