A phase II study of liposomal doxorubicin in the treatment of HIV-related Kaposi's sarcoma

OBJECTIVES

To evaluate the toxicity and clinical efficacy of liposomal encapsulated doxorubicin (DOX-SL) in the treatment of HIV-related Kaposi's sarcoma (KS).

METHODS

DOX-SL 20-40mg/m2 was administered by intravenous infusion over 30-60 minutes every two weeks. Toxicity was assessed in all patients and response assessed in patients who completed two or more cycles of therapy.

RESULTS

Twenty-five patients with KS were enrolled. Nine had received previous KS chemotherapy but only one prior anthracycline therapy. Eighteen patients had CD4 counts < 50/mm3. Eight had pulmonary and/or visceral KS. A total of 191 cycles were given, median 6, range 1-33. Twenty patients completed two or more cycles and were considered evaluable for efficacy. A defined response occurred in 11 patients, nine achieving a partial response and two a complete response. The median duration of response was 120 days and the median time to disease progression was 187 days. Acute toxicity was minimal, except in one patient who had generalised erythema, hypotension and diaphoresis within ten minutes of starting DOX-SL infusion. Grade 3 or 4 neutropenia occurred in 13.6 and 3.7% of cycles respectively. Neutropenic sepsis secondary to drug therapy was not reported. Alopecia and gastrointestinal symptoms were mild and infrequent. No cardiac toxicity was seen. Nine/25 patients developed HIV-associated illnesses while on study (three Pneumocystis carinii pneumonia, two systemic Cytomegalovirus infection, three cryptosporidiosis, one Mycobacterium avium intracellulare--(MAC) infection). Median survival in the evaluable patients was 219 days.

CONCLUSIONS

DOX-SL is an effective and well tolerated palliative therapy in AIDS-related KS.

Establishing minimum performance standards, calibration intervals, and optimal exposure values for a whole breast digital mammography unit

Methods are developed to establish minimum performance standards, calibration intervals, and criteria for exposure control for a whole breast digital mammography system. A prototype phantom was designed, and an automatic method programmed, to analyze CNR, resolution, and dynamic range between CCD components in the image receptor and over time. The phantom was imaged over a 5 month period and the results are analyzed to predict future performance. White field recalibration was analyzed by subtracting white fields obtained at different intervals. Exposure effects were compared by imaging the prototype phantom at different kVp, filtration (Mo vs Rh) and mAs. Calcification detection tests showed that phantom images, obtained at 28 kVp with a Mo/Mo anode/filter and low mAs technique, often could not depict Al2O3 specks 0.24 mm in diameter, while a 28 kVp Mo/Rh, higher mAs technique usually could. Stability of the system tested suggests that monthly phantom imaging may suffice. Differences in CCD performance are greater (12%) than differences in a single CCD over time (6%). White field recalibration is needed weekly because of pixel variations in sensitivity which occur if longer intervals between recalibration occur. When mean glandular dose is matched, Rh filtration gives better phantom performance at 28 kVp than Mo filtration at 26 kVp and is recommended for clinical exposures. An aluminum step wedge shows markedly increased dynamic range when exit exposure is increased by using a higher energy spectrum beam. Phantoms for digital mammography units should cover the entire image receptor, should test intersections between components of the receptor, and should be automatically analyzed.

Removal of a Norplant implant located near a major nerve using interventional radiology-digital subtraction fluoroscopy

Norplant implants can be removed easily, if inserted properly. When they are inserted deeply and can not be palpated, or if they are located close to the neurovascular structures of the upper arm, radiological guidance may be needed to locate and remove the implants without causing injury to the surrounding vital structures. Digital subtraction fluoroscopic guidance is helpful in removing deeply located contraceptive implants and those that are close to the neurovascular structures, where blind removal may result in injury to those structures. We describe a case in which an implant that was located close to a major nerve near the axilla was removed under digital subtraction fluoroscopic guidance.

Discrete domains within the hyaluronan receptor CD44 regulate membrane localization and cell migration

CD44 is the principle transmembrane receptor for the extracellular matrix glycosaminoglycan, hyaluronan. This receptor: ligand interaction is required for many normal cellular processes including lymphocyte homing into inflammatory sites, assembly of a pericellular matrix during chondrogenesis, wound healing and tissue morphogenesis during development. In order to mediate these diverse events, CD44 expressing cells must be able to regulate, and respond to, interactions with hyaluronan. The mechanisms responsible have been subject to scrutiny over the past few years as it has become clear that their disruption can underlie the progression of both metastatic tumours and chronic inflammatory diseases. Here we describe recent data identifying discrete regions within the transmembrane and cytoplasmic domains of CD44 which regulate this important adhesion receptor.

Rural epidemiology: insights from a rural population laboratory

To study the epidemiology of rural populations in the context of contemporary issues in public health, a population laboratory (Health Census '89) was established in Otsego County, New York, by the Research Institute of the M.I. Bassett Hospital, affiliated with the Columbia University School of Public Health. Such a laboratory is needed because of an apparent lag in positive health indices in rural populations across the United States, resulting in rates of chronic diseases, such as coronary heart disease, for which rural areas now exceed urban ones. This was confirmed for Otsego County by the survey Health Census '89, the foundation of a rural population laboratory, in which all residents were enumerated and characterized as to their prevalent diseases, health behaviors, use of preventive services, and environmental exposures. Heart disease, cancer, and diabetes mellitus rates were found to exceed average rates for US urban areas, while the data on preventive health behaviors suggest this is a population of "late adopters." The survey, conducted in 1989, had an 86.6% response rate, and enumerated 17,147 households and 44,406 persons. The authors discuss adults aged 17-64 years, 58 percent of the total census (n=25,614). Sharp gradients in disease prevalence, risk factors, and utilization of preventive services were observed across educational strata. Data from Health Census '89 were used as the basis for a successful community intervention program, which targeted identified high risk groups. Rural populations are excellent settings for community interventions, offering laboratories where new strategies of risk reduction and provision of preventive services might be tested.

Help-seeking decisions among men with impotence

OBJECTIVES

There is a paucity of valid contemporary data concerning the proportion of impotent men who seek treatment. The aim of this study was to determine the proportion of impotent men who sought treatment, from whom they sought treatment, and their reasons for seeking or not seeking treatment.

METHODS

A self-administered survey of 5198 randomly selected men between 50 and 76 years old, living in four rural counties in central New York State, was used.

RESULTS

The sample included 649 men who reported having experienced impotence in the 6 months preceding the study period (November 1996 to June 1997). The mean age of these men and mean duration of impotence were 64.5+/-7.2 and 4.9+/-4.6 years, respectively. Two hundred five men (31.6%) had sought treatment, 432 (66.6%) had not, and 12 (1.8%) neglected to answer the question. Most first consulted with either their primary care provider (44.7%) or a urologist (40.7%). Among those who had sought treatment, 36.3% were satisfied, 48.4% were dissatisfied, and 15.2% were neither satisfied nor dissatisfied with the results. The primary reasons for seeking treatment were to improve their self-esteem (44.8%), awareness of a new treatment (33.4%), partner insistence ( 11.3%), and coverage by their health insurance (10.4%). The reasons for not seeking treatment were embarrassment (29.8%), ignorance or misinformation (45.2%), and lack of affordability (25.0%).

CONCLUSIONS

Despite increased availability of effective treatment, most men with impotence do not seek treatment, and among those who do, only 36.3% are satisfied with the results.

The effect of family structure on linkage tests using allelic association

We considered the problem of testing a marker for linkage with a disease, using tests based on the transmission-disequilibrium test (TDT). The power of such tests was investigated for a number of possible family types, for which the families were classified by the disease status of family individuals. We show that parental disease status greatly affects the power, with families containing a single affected parent often preferred over families in which neither parent is affected. Families with a pair of affected sibs are of great value for all situations considered, but extension of the TDT to allow inclusion of information from unaffected sibs rarely increases power, if the parents have been genotyped.

Correlation of SMNt and SMNc gene copy number with age of onset and survival in spinal muscular atrophy

Childhood-onset autosomal recessive spinal muscular atrophy (SMA) is associated with absence of the telomeric survival motor neuron gene (SMNt) in most patients, and deletion of the neuronal apoptosis inhibitory protein (NAIP) gene in the majority of severely affected patients. Analysis of SMNt has been complicated by the existence of a centromeric copy, SMNc, which is almost identical to SMNt but which can be distinguished from it by restriction enzyme analysis. In this study 143 SMA patients have been genotyped for the presence or absence of the SMNt, SMNc and NAIP genes, and the data correlated with quantifiable clinical variables. Although a significant correlation was observed between the presence or absence of the NAIP gene and the severity of the clinical phenotype in SMA patients generally, there was no difference in age of onset or survival in type I patients with the NAIP+ or NAIP- genotype. Fluorimetric PCR analysis of SMNc gene dosage in 57 patients homozygous for the absence of the SMNt gene but in whom the NAIP gene was present showed a highly significant correlation between SMNc copy number and SMA subtype, and between SMNc copy number and both age of onset and length of survival. The data provide strong statistical support for the emerging consensus that the clinical phenotype in SMA is directed primarily by the level of functional SMN protein. The lower SMNc copy number in type I patients in whom the NAIP gene is present suggests that the SMNt gene is removed by deletion in the majority of such patients, rather than by gene conversion as is the case in SMA types II and III.

Differential rescue of visceral and cardiac defects in Drosophila by vertebrate tinman-related genes

tinman, a mesodermal NK2-type homeobox gene, is absolutely required for the subdivision of the early Drosophila mesoderm and for the formation of the heart as well as the visceral muscle primordia. Several vertebrate relatives of tinman, many of which are predominately expressed in the very early cardiac progenitors (and pharyngeal endoderm), also seem to promote heart development. Here, we show that most of these vertebrate tinman-related genes can readily substitute for Drosophila tinman function in promoting visceral mesoderm-specific marker gene expression, but much less in promoting cardiac-specific gene expression indicative of heart development. In addition, another mesodermal NK2-type gene from Drosophila, bagpipe, which is normally only needed for visceral mesoderm but not heart development, cannot substitute for tinman at all. These data indicate that the functional equivalence of the tinman-related subclass of NK2-type genes (in activating markers of visceral mesoderm development in Drosophila) is specific to this subclass and distinct from other homeobox genes. Despite the apparent overall conservation of heart development between vertebrates and invertebrates, the differential rescue of visceral mesoderm versus heart development suggests that some of the molecular mechanisms of organ formation may have diverged during evolution.

Receptor-mediated folate uptake is positively regulated by disruption of the actin cytoskeleton

Receptor-mediated folate uptake is initiated by binding of ligand to a glycosyl phosphatidylinositol-anchored protein, folate receptor alpha (FR alpha). This receptor is expressed in a limited number of normal tissues but is overexpressed in a large number of epithelial malignancies. FR alpha synthesis, at least in part, is regulated by endogenous folate and by hormones in some cells, but much less is known about the control of function. Recently, we showed that phorbol 12-myristate 13-acetate increases the rate of receptor cycling, increases the rate of folate delivery, and causes the majority of the receptor to reside on the cell surface in nonmalignant cells in vitro (C. M. Lewis et al., Biochim. Biophys. Acta, 1401: 157-169, 1998). However, based upon effects (or lack of effects) of specific inhibitors of protein kinase C, the mechanism of action of phorbol 12-myristate 13-acetate is not likely via protein kinase C. Because exo- and endocytosis are controlled by the actin cytoskeleton, we tested cytochalasin D and latrunculin B, actin-disrupting agents, on FR alpha-mediated folate uptake. Disruption of the actin cytoskeleton reversibly increases the proportion of receptors on the cell surface and increases the rate of 5-methyltetrahydrofolate delivery. Disrupting microtubules with nocodazole had no effect. The increased rate of folate delivery caused by cytochalasin D is not observed in FR-negative cell lines. Although we have not yet identified the upstream effectors, likely candidates include small G-proteins such as rho, which are known to cause actin polymerization. In addition to identifying the machinery for receptor-mediated folate uptake, it may be important to integrate this new data into studies of FR alpha as a tumor antigen for imaging or delivering molecules via anti-FR antibodies or compounds coupled to folic acid.

Mathematics anxiety and working memory: support for the existence of a deficient inhibition mechanism

A current theory of anxiety effects in cognition claims that anxiety disrupts normal processing within the working memory system. We examined this theory in the context of a reading task, for participants who were high or low in assessed mathematics anxiety. The task was designed to measure the ability to inhibit attention to distracting information and the effects of this ability on explicit memory performance. The results suggested that math-anxious individuals have a deficient inhibition mechanism whereby working memory resources are consumed by task-irrelevant distracters. A consequence of this deficiency was that explicit memory performance was poorer for high-anxious individuals. Based on these results, the recommendation is made that Eysenck and Calvo's (1992) processing efficiency theory be integrated with Connelly, Hasher, and Zack's (1991) inhibition theory to portray more comprehensively the relation between anxiety and performance.

Response to radiation therapy and prognosis in breast cancer patients with BRCA1 and BRCA2 mutations

BACKGROUND AND PURPOSE

The purpose of this study is to evaluate overall survival in BRCA1 or BRCA2 breast cancer patients, describe presenting stage, review histologic findings and evaluate response to radiotherapy.

MATERIALS AND METHODS

A retrospective study was performed evaluating breast cancer patients with known mutations of BRCA1 or BRCA2. Patients from 12 different pedigrees were cross-referenced with the Utah Cancer Registry (UCR), histologic findings were verified and radiotherapy records were reviewed for acute response to treatment. Actuarial survival calculations were performed and patients were matched for age, date of diagnosis and tumor size.

RESULTS

Thirty breast cancer patients with BRCA1 mutations were found to have 34 breast cancers (four had bilateral metachronous lesions) and 20 breast cancer patients with BRCA2 mutations were found to have 22 breast cancers (two had bilateral metachronous disease). The median age at diagnosis was 49 years (range 21-77 years) and 42 years (range 23-83 years), respectively, for BRCA1 and BRCA2 patients. Unusual histologic types of breast cancers were represented with 7% (4/56) medullary and 5% (3/56) lobular carcinomas. Complete staging was possible for 63% (35/56) of cancers. Stages I, II, III and IV represented 26, 63, 6 and 6% of cancers, respectively. The most severe radiation reaction was moist desquamation which was self-limiting and developed in 29% (6/21) of irradiated patients. The mean follow-up was 9.8 and 7.5 years for BRCA1 and BRCA2 cancers, respectively. Kaplan-Meier survival analysis demonstrated 5-year survival values of 75% for BRCA1 patients, 73% for BRCA2 patients, 70% for matched controls and 69% for UCR controls. No statistically significant differences were evident between the groups at 5 or 10 years.

CONCLUSIONS

Despite their younger age at presentation, breast cancer patients harboring BRCAI or BRCA2 mutations present at a similar stage, display a normal acute reaction to radiotherapy and have a similar prognosis when compared with sporadic breast cancer patients.

Does day case surgery generate extra workload for primary and community health service staff?

We have audited the effects of day surgery on the workload of primary and community care teams in Portsmouth. A modified version of the Audit Commission's 'Patients' Experiences of Surgery' questionnaire was given to all patients admitted for an elective surgical procedure from 16 general practices to the two local hospitals between February and November 1996; 487 completed replies were received. In all, 50% patients consulted primary or community health care staff within 21 days of discharge from hospital. The average total patient contact rate with these staff increased with length of hospital stay from 0.39 contacts/patient for day case to 1.83 contacts/patient for longer stay admissions. Contacts with most members of the primary and community health teams increased with length of hospital stay. The postoperative visit rate by general practitioners and district nurses to day case patients was very low. We conclude that day case surgery at its present level in Portsmouth appears to create less workload for primary and community health services than inpatient surgery.