Skull base tumor volume and surgical margins: a pilot study

The relationship between preoperative assessment of tumor volume and oncologic adequacy of surgical margins was studied retrospectively. Our hypothesis was that the risk of inadequate, or positive, margins would rise with increasing tumor volume and that this would adversely affect survival. We anticipated that limitations of surgical approaches used until 1988 would be reflected in an increasing proportion of positive margins with increasing tumor volume. We conducted a pilot study of 25 patients with malignant tumors of the anterolateral cranial base operated on at the University of Pittsburgh Center for Cranial Base Surgery between 1987 and 1988. Preoperative computed tomography assessment of tumor volume was performed in all patients, and correlation between tumor volume, surgical margins, and survival was examined. Follow-up interval averaged 31.7 months. Twelve histologic tumor types were represented, with squamous cell carcinoma the most common (eight patients [32%]). Tumor volume ranged from 0.9 to 390 cc, with a median of 48 cc. Based on a median split of tumor volumes, patients were classified as high volume (more than 48 cc) or low volume (less than 48 cc). Of patients in the high volume group, 92% were found to have positive surgical margins, whereas only 50% of patients in the low volume group had positive margins. Analysis of the effect of tumor volume and surgical margins on survival was limited by sample size constraints, but both high-tumor volume and positive margins tended to reduce patient survival (0.07 < p 0.10).

Use of basiliximab with mycophenolate mofetil in kidney transplantation

INTRODUCTION

Randomized, placebo-controlled studies have determined that administration of basiliximab (chimeric IL-2 receptor antagonist) decreases the acute rejection rate in kidney transplantation when used in combination with cyclosporine, azathioprine, and steroids. We report our experience using basiliximab with mycophenolate mofetil, a calcineurin inhibitor, and steroids in kidney transplantation.

METHODS

We retrospectively analyzed 127 patients who received their first kidney transplant between September 1, 1998, and December 30, 2000, including 59 who received basiliximab (22 living and 37 cadaveric donor recipients) and the 68 that did not receive this antibody (31 living and 37 cadaveric donor recipients). The groups were demographically comparable for risk factors such as race, peak of panel-reactive antibody, delayed graft function, donor age, and cold ischemia time. The analysis assessed serum creatinine levels, acute rejection, cytomegalovirus infection, and posttransplant lymphoproliferative disease incidence as well as patient and graft survival at 6 months.

RESULTS

Serum creatinine levels were 3 +/- 3.1 and 2.6 +/- 2.5 mg/dL (P =.346) at discharge, 1.5 +/- 0.6 and 1.7 +/- 1.1 mg/dL (P =.098) at 1 month, and 1.5 +/- 0.7 and 1.6 +/- 0.7 mg/dL (P =.454) at 6 months posttransplantation for patients treated with versus without basiliximab, respectively. Only one episode of acute rejection was seen among patients treated with basiliximab within 1 month posttransplantation versus three episodes among patients treated without basiliximab (P =.382). Three patients (5.1%) treated with basiliximab and two patients (2.9%) treated without basiliximab developed acute rejection within 6 months posttransplantation (P =.536). Patient and graft survivals at 6 months posttransplantation were not significantly different between patients treated with versus without basiliximab (100% and 100% versus 100% and 98.3%, respectively). There was no increased incidence of cytomegalovirus infection with the use of basiliximab (5.1% vs 5.9%, P =.844). There was only one case of posttransplant lymphoproliferative disease within 6 months posttransplantation in a patient treated without basiliximab.

CONCLUSION

These data suggest that the routine addition of basiliximab to a mycophenolate mofetil-based regimens does not appear to be warranted. A larger prospective randomized study with longer follow-up is needed to confirm these results.

Prevalence of short-segment Barrett's epithelium

BACKGROUND/AIMS

The incidence of adenocarcinoma of the oesophagus has increased. Its major risk factor is Barrett's epithelium of which the sine qua non is microscopically diagnosed intestinal metaplasia. Short segment Barrett's epithelium may often be overlooked during routine endoscopy. In routine biopsies taken from normal-appearing mucosa of the distal oesophagus, the reported rates of short segment Barrett's epithelium in the distal oesophagus reached 36%. We compared these rates with the results obtained in a community hospital in Israel.

METHODS

Consecutive patients undergoing oesophagogastroduodenoscopy were enrolled. Biopsy specimens taken from cardia, oesophagogastric junction and 2 cm above the oesophagogastric junction were stained with haematoxylin & eosin and Alcian blue.

RESULTS

There were 112 study patients (mean age +/- SD 48. 9+/-18.3 years, 51.8% males). Nine (8.04%) patients had intestinal metaplasia (according to specimen from 2 cm above oesophagogastric junction), and symptoms of gastro-oesophageal reflux were found in only four (44.4%) of them. Of these nine patients, six (6.66%) had normal-appearing mucosa and three (3.33%) had macroscopic Barrett's epithelium. Alcian blue staining revealed two patients with intestinal metaplasia that haematoxylin & eosin staining had missed.

CONCLUSION

We found an 8% prevalence of intestinal metaplasia compared to 18-36% reported in the literature. We also determined that the added advantage of routine biopsy was 5.4%.

Stage-specific assays to study biosynthetic cargo selection and role of SNAREs in export from the endoplasmic reticulum and delivery to the Golgi

To analyze the role of coat protein type II (COPII) coat components and targeting and fusion factors in selective export from the endoplasmic reticulum (ER) and transport to the Golgi, we have developed three novel, stage-specific assays. Cargo selection can be measured using a "stage 1 cargo capture assay," in which ER microsomes are incubated in the presence of glutathione S-transferase (GST)-tagged Sar1 GTPase and purified Sec23/24 components to follow recruitment of biosynthetic cargo to prebudding complexes. This cargo recruitment assay can be followed by two sequential assays that measure separately the budding of COPII-coated vesicles from ER microsomes (stage 2) and, finally, delivery of cargo-containing vesicles to the Golgi (stage 3). We show how these assays provide a means to identify the snap receptor (SNARE) protein rBet1 as an essential component that is not required for vesicle formation, but is required for vesicle targeting and fusion during ER-to-Golgi transport. In general, these assays provide an approach to characterize the biochemical basis for the recruitment of a wide variety of biosynthetic cargo proteins to COPII vesicles and the role of different transport components in the early secretory pathway of mammalian cells.

Origin of the West Nile virus responsible for an outbreak of encephalitis in the northeastern United States

In late summer 1999, an outbreak of human encephalitis occurred in the northeastern United States that was concurrent with extensive mortality in crows (Corvus species) as well as the deaths of several exotic birds at a zoological park in the same area. Complete genome sequencing of a flavivirus isolated from the brain of a dead Chilean flamingo (Phoenicopterus chilensis), together with partial sequence analysis of envelope glycoprotein (E-glycoprotein) genes amplified from several other species including mosquitoes and two fatal human cases, revealed that West Nile (WN) virus circulated in natural transmission cycles and was responsible for the human disease. Antigenic mapping with E-glycoprotein-specific monoclonal antibodies and E-glycoprotein phylogenetic analysis confirmed these viruses as WN. This North American WN virus was most closely related to a WN virus isolated from a dead goose in Israel in 1998.

Clinical research in medical schools: seizing the opportunity

Academic medical centers (AMCs) face challenges to the achievement of their potential in clinical research. These challenges include reduced support of research from clinical revenue, cultural impediments to clinical research within the traditional value system of research-intensive AMCs, and potential problems of patient access to clinical research in intensive managed care environments. This article considers options to strengthen clinical research that have been developed at some medical centers. While much attention is being directed to the expansion of clinical trials in many AMCs, this effort needs to be linked to a cohesive strategy for clinical research being conducted in an academic environment. The article also addresses the subject of training and career development. It concludes with the opinion that the "crisis" in clinical research in academic medical centers provides the opportunity to define, more explicitly, the nature and scope of the investment in clinical research, and to define strategies that will bring added value to knowledge generated from basic research and to the teaching and patient care missions of these centers.

Sphenoclival Rathke's cleft cysts: embryology, clinical appearance and management

In summary, Rathke's cleft cysts in the extracranial skull base are rare. Untreated, they can grow to involve structures in the sphenoclival region or the cavernous sinus. Surgical removal via an approach that offers maximal visualization and minimal morbidity affords the best treatment for patients with such lesions.

Cargo selection by the COPII budding machinery during export from the ER

Cargo is selectively exported from the ER in COPII vesicles. To analyze the role of COPII in selective transport from the ER, we have purified components of the mammalian COPII complex from rat liver cytosol and then analyzed their role in cargo selection and ER export. The purified mammalian Sec23-24 complex is composed of an 85-kD (Sec23) protein and a 120-kD (Sec24) protein. Although the Sec23-24 complex or the monomeric Sec23 subunit were found to be the minimal cytosolic components recruited to membranes after the activation of Sar1, the addition of the mammalian Sec13-31 complex is required to complete budding. To define possible protein interactions between cargo and coat components, we recruited either glutathione-S-transferase (GST)-tagged Sar1 or GST- Sec23 to ER microsomes. Subsequently, we solubilized and reisolated the tagged subunits using glutathione-Sepharose beads to probe for interactions with cargo. We find that activated Sar1 in combination with either Sec23 or the Sec23-24 complex is necessary and sufficient to recover with high efficiency the type 1 transmembrane cargo protein vesicular stomatitis virus glycoprotein in a detergent-soluble prebudding protein complex that excludes ER resident proteins. Supplementing these minimal cargo recruitment conditions with the mammalian Sec13-31 complex leads to export of the selected cargo into COPII vesicles. The ability of cargo to interact with a partial COPII coat demonstrates that these proteins initiate cargo sorting on the ER membrane before budding and establishes the role of GTPase-dependent coat recruitment in cargo selection.

Relationship between health status and utility measures in older claudicants

The purpose of this study was to examine the relationship between health status and health utility measures in 34 older claudicants and to determine which attributes of health status were significant predictors of health state valuation/preference. The MOS SF-36 was used to assess health status and the rating scale and multiattribute Health Utility Index (HUI) were used to assess utility scores. With regard to health status, the bodily pain and physical functioning subscales contributed the most to reductions in quality of life (QoL) with mean subscale scores substantially lower than reported population norms. Patients rated their health status approximately one-third below a state of perfect health on both utility measures. Moderate correlations were observed between the MOS SF-36 subscale scores and the HUI and rating scale scores. In multivariable regression models, physical functioning and mental health were the best predictors of HUI scores, whereas general health and vitality were the best predictors of rating scale scores. Approximately 50% of the variance in utility scores was explained by these attributes. This study provides further documentation that bodily pain and reductions in physical function contribute to reductions in QoL in older patients with intermittent claudication. Other attributes of health status, however, notably psychological distress, were predictive of patients' preference for health states. Recognized constructs of physical and mental health explained the substantial variation in the utility/preference assessment in this population. Furthermore, these data are consistent with those reported in the Dutch Iliac Stent Trial.

An impact evaluation of project SNAPP: an AIDS and pregnancy prevention middle school program

OBJECTIVES

A theory-based curriculum designed to delay the onset of intercourse and increase use of condoms was implemented in the classrooms of six Los Angeles middle schools.

METHODS

The curriculum activities were very interactive, emphasized skill building, and were implemented by well trained peer educators, including young HIV-positive males and teen mothers. To evaluate the impact of the curriculum, 102 classrooms of students were randomly assigned to receive either the existing curriculum or the existing curriculum plus the intervention curriculum. Students completed confidential questionnaires before program implementation, five months later, and 17 months later. A total of 1,657 students completed both the baseline and 17-month follow-up questionnaires.

RESULTS

Analyses of these data revealed that the curriculum significantly increased knowledge, significantly improved only two out of 21 attitudes or beliefs, and did not significantly change sexual or contraceptive behaviors.

CONCLUSIONS

Well implemented programs that are based on upon theory, use interactive activities, and utilize well-trained peer educators do not always change important sexual attitudes and behaviors among middle school youth.

Uncompensated hospital care. Will it be there if we need it?

The debates over health care system reform continue, but they rarely mention the enduring need for free or reduced-cost hospital care as a safety net for uninsured and underinsured individuals. Policy changes on numerous fronts threaten the ability or willingness of hospitals to provide uncompensated care. These changes include the decline of Hill-Burton funds, the closings or mergers of not-for-profit and public hospitals, the dominance of competitive forces, and the redirection of funds intended for disproportionate share hospitals or uncompensated pools. Federal and state governments lack coordinated approaches toward uncompensated care, and health system reforms may not have the expected effects on reducing hospitals' burden of paying for services to indigents. Furthermore, measurement of uncompensated care is inconsistent. In light of the persistent growth in the number of persons with inadequate health insurance coverage and the central role that uncompensated care will continue to play in ensuring access to care for the poor and uninsured, these policies need to be reexamined. Guidelines for policy based on past experience are presented herein.

Experimental acidemia and muscle cell pH in chronic acidosis and renal failure

To test whether muscle intracellular pH (pHi) decreases when extracellular pH falls, 31P-nuclear magnetic resonance was utilized in rats made acidotic by infusion of HCl, gavage-feeding NH4Cl, or induction of chronic renal failure (CRF). A 2- or 4-h HCl infusion did not lower muscle pHi, even though serum bicarbonate fell to 5 mM. With chronic acidemia, blood pH was 7.15 +/- 0.01 vs. 7.38 +/- 0.02 in pair-fed controls, and muscle pHi was 7.09 +/- 0.01 and 7.14 +/- 0.02, respectively (P < 0.01). pHi in muscle of CRF rats (7.16 +/- 0.01) did not differ from sham-operated, pair-fed controls (7.19 +/- 0.01) despite a blood pH of 7.23 +/- 0.05 in CRF vs. 7.39 +/- 0.01 in controls. Because ion transport is abnormal in CRF, we examined whether recovery of pHi is impaired when muscles of six CRF and control rats were exercised to tetany by stimulation of the sciatic nerve. Neither pHi nor the recovery of pHi differed between CRF and control rats. We conclude that pHi is maintained in muscle in uremia and that signals other than changing pHi must be necessary to disrupt metabolism.

The role of reluctance to give up life in the measurement of the values of health states

Questions that involve willingness to risk or give up life often are used to measure the values of health states. In the Boston Health Study, interviews with 291 patients who had AIDS included questions about health status and current desire for resuscitation, and a series of hypothetical questions about desire for life-extending efforts if the patients found themselves in undesirable states, such as being chronically nauseous or blind. An index, "reluctance to give up life" was made from five such questions. The desire for resuscitation was related to current health status, but the general reluctance to give up life was not. Desire to be resuscitated was significantly related to current health status only when "reluctance to give up life" was "low." For people reluctant to say they will give up any life at all, questions that involve risking or trading life seem likely to be poor measures of the values of health states.

Iodoacetate-induced skeletal muscle contracture: changes in ADP, calcium, phosphate, and pH

The effects of iodoacetic acid (IAA) and ischemic contraction were studied in rat extensor digitorum longus muscles. Ischemic stimulation of IAA-treated muscles produced contracture. We measured total muscle water content, distribution of water between intracellular and extracellular spaces, creatine concentration ([Cr]), creatine phosphate concentration ([PCr]), [ATP], [Pi], intracellular pH, and intracellular Ca2+ concentration ([Ca2+]i) at the onset of contracture. [ADP] was calculated from the equilibrium of the creatine kinase reaction using the measured values of [ATP], [PCr], [Cr], and pH. At the onset of contracture there was a 75% reduction of [PCr], a 12-fold increase in [ADP], and an 11-fold increase in [Ca2+]i compared with unstimulated IAA-treated muscles. [ATP] was not depleted at contracture compared with unstimulated IAA-treated muscles, and [Pi] increased less in muscles at contracture compared with stimulated control muscles. The persistent tension in contractures probably resulted from increased [Ca2+]i combined with increased myofibrillar Ca2+ sensitivity due to elevated [ADP] and relatively reduced intracellular acidification and [Pi].

The therapeutic aspects of acceptance

PROBLEM

What does acceptance mean to hospitalized adolescents?

METHODS

Using a phenomenological research approach, the authors asked hospitalized adolescents (N = 6) on a psychiatric unit to describe how acceptance from psychiatric-mental health nurses was experienced by them.

FINDINGS

Three essential themes emerged: (a) the nurse who shows acceptance is seen as a friend, (b) acceptance generates a sense of well-being, and (c) acceptance produces feelings of comfort with the nurse.

CONCLUSIONS

In acceptance, adolescents experience nurses as unique individuals who provide comfort and nurturing. This relationship connection helps adolescent clients to use their inner strength to gain a sense of well-being.

Utilization of formal and informal home care by AIDS patients in Boston: a comparison of intravenous drug users and homosexual males

The assumption that intravenous (i.v.) drug users have weaker informal support networks than homosexual men has led to opposing policy recommendations: one emphasizes outreach and more formal (paid) home care for i.v. drug users, whereas the other maintains that formal home care programs are less effective for this risk group due to the lack of informal (unpaid) caregivers to coordinate efforts. Data from interviews with a sample of 231 persons with AIDS in the Boston area were used to compare the use of formal and informal home care between the two largest risk groups, homosexual men and i.v. drug users. Multivariate regression analysis was also employed to adjust estimates and to determine the significance of population characteristics in explaining utilization differences. IV drug users received about twice as much formal and informal home care as homosexual men. Controlling for functional status, income and assets, insurance and potential caregiver supply, i.v. drug users obtained significantly fewer formal home care services, but more informal care. Overall, i.v. drug users received a greater number of adjusted home care hours. These findings cast doubt upon the previous assumptions of the literature and suggest that members of both risk groups are appropriate candidates for formal home care services.

Health-related quality of life in persons with acquired immune deficiency syndrome

Assessing health-related quality of life in persons infected with human immunodeficiency virus (HIV) is extremely important, but most available scales are too long, contain items that are not relevant for such persons, or do not assess important signs and symptoms of HIV infection. This study presents a new set of scales for assessing the symptoms and functioning of persons infected with HIV and reports data on their reliability and validity collected in face-to-face interviews with 189 patients receiving primary care. This study also assesses the associations among systems, functional impairment, and global health assessments. The scales are easy to administer, are reliable, and serve as valid measures of quality of life. Fatigue, functional status, and average severity of all symptoms were the best predictors of overall perceived health status. Psychological well-being and perceived health status were the best predictors of overall perceived health status. Psychological well-being and perceived health status were the strongest correlates of life satisfaction. When assessing the health-related quality of life of persons infected with HIV, this study recommends utilizing a comprehensive set of measures that allows one to examine both discrete symptoms and the more diffuse impact of illness on functioning, mental health, and quality of life.

Jugular foramen syndrome as a complication of metastatic melanoma

INTRODUCTION

The jugular foramen (Vernet) syndrome with neuropathy of cranial nerves IX-XI is more commonly due to metastatic lesions than primary neoplasms. Hypoglossal nerve involvement is referred to as the Collet Sicard variant of the jugular foramen syndrome.

MATERIALS AND METHODS

We report an elderly man who presents with dysphagia, dysarthria, hoarseness, and a 12-pound weight loss. Examination demonstrated paralysis of the right vagus and hypoglossal nerve. Communication and collaboration with the radiologist resulted in identification of the lesion. Computed tomographic (CT) guided needle aspiration confirmed metastatic melanoma.

DISCUSSION

The onset of cranial neuropathy may allow the site of lesion to be predicted based on knowledge of the cranial base and neural anatomy. Diagnostic evaluation is tailored to evaluate the area in question. Active, multidisciplinary collaboration is essential for success.

Response time of pulse oximeters assessed using acute decompression

In human volunteers, the response times of 11 pulse oximeters to a 10% step reduction in arterial oxygen saturation were measured using an acute decompression technique. When finger probes were used, nine oximeters had similar response times and two were significantly slower (P less than 0.05). The ear probe response time was similar on six oximeters assessed, and faster than the finger probes. The response times of the oximeters to an acute increase in arterial saturation were tested by suddenly changing the inspired gas from air to 100% oxygen at an ambient pressure of 380 mm Hg. For ear probes, the response times were similar for all oximeters; for finger probes, three fast-responding and three slow-responding oximeters were identified (P less than 0.05). A faster response could be elicited by placing the probes on the thumb (P less than 0.05). We conclude that if a rapid indication of changes in arterial saturation is required, pulse oximeters with ear probes should be used. If finger probes are used, they should be placed on the thumb. The oximeter used will influence the response time if finger probes are used, but it will have little effect if ear probes are used.

Iodoacetate-induced contracture in rat skeletal muscle: possible role of ADP

The effects of iodoacetic acid (IAA) and ischemic contraction were studied in rat extensor digitorum longus muscles. Ischemic contraction of IAA-treated muscles produced contracture. The onset of contracture was not associated with a change in sarcolemmal electrical properties or reduction in intracellular [ATP]; however, [creatine phosphate] was reduced by 75% and free [ADP] was increased by 665%. Continued stimulation of IAA-treated fibers resulted in depolarization, loss of membrane excitability, further depletion of creatine phosphate, and reduction in [ATP]. The effects seen in IAA-treated muscle did not appear to result from a direct action of IAA on the surface membrane, contractile proteins, or excitation-contraction coupling. The contractures in IAA-treated muscle may have resulted from increased Ca sensitivity of the contractile proteins, increased myoplasmic [Ca], or both. Both effects may have resulted from increased [ADP]. In addition, the reduced acidification during ischemic contraction of IAA-treated fibers compared with control fibers may have further increased the Ca sensitivity of IAA-treated fibers compared with controls.

Lack of effect of cyclophosphamide on the immunogenicity of a melanoma antigen vaccine

Melanoma antigen vaccines are a conceptually attractive approach to prevent or delay disease recurrence in patients with surgically resected malignant melanoma. However, the immunogenicity of current vaccines is relatively low. Cyclophosphamide, when given in low doses prior to antigen exposure, is an immunomodulator which has been shown to enhance both humoral and cellular antitumor responses in animals and humans. We conducted a prospective, randomized, clinical trial to study whether pretreatment with cyclophosphamide augments the immunogenicity of a polyvalent, allogeneic, melanoma antigen vaccine in patients with melanoma and low tumor burden. Forty-five patients with resected stage II melanoma (regional metastases) were randomly allocated to treatment with melanoma vaccine or melanoma vaccine plus cyclophosphamide. All patients received the same dose and schedule of vaccine immunizations; those randomized to cyclophosphamide received 300 mg/m2 i.v. 3 days prior to each vaccine immunization. Cellular immune responses were evaluated by delayed-type hypersensitivity (DTH) skin reactivity to a test dose of vaccine at baseline (prior to treatment) and following the fourth immunization. Humoral immune responses were measured by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiographic analysis of indirect immunoprecipitates of patients' sera at the same time points. Twenty-four patients were randomized to cyclophosphamide pretreatment and 21 to vaccine alone; 22 and 18 patients were evaluable in each group, respectively. Differences were statistically nonsignificant with respect to either cellular (DTH) or humoral (antibody) responses between the two groups. DTH responses were induced in 16 of 22 (73%) and 15 of 18 (83%) patients treated with cyclophosphamide plus vaccine and vaccine alone, respectively. The mean posttreatment augmentation in DTH response in the cyclophosphamide group was 9.5 mm, compared with 9.9 mm in the vaccine-only group. Eight of 12 (66%) cyclophosphamide-pretreated patients and 9 of 12 (75%) vaccine-only patients produced increased titers of antimelanoma antibodies following treatment. No differences were observed between the groups in disease-free or overall survival. In summary, low-dose cyclophosphamide pretreatment failed to augment the immunogenicity of a polyvalent, allogeneic, melanoma vaccine in patients with completely resected early-stage melanoma.

Acute aortic thrombosis causing sudden paraplegia in a patient with known thoraco-lumbar spinal metastasis: the diagnostic usefulness of magnetic resonance imaging

Diagnosis and treatment of acute aortic thrombosis utilizing magnetic resonance imaging is reported. The patient had known thoracolumbar spinal metastases and sudden onset paraplegia. MRI critically shortened the time to emergent surgery and obviated the need for two invasive tests (myelogram and angiogram).

Case mix and resource utilization by uninsured hospital patients in the Boston metropolitan area

Rising competitive pressures may place uninsured patients at risk for receiving fewer services than insured patients with similar medical conditions. To examine this possibility we studied the case mix, length of stay, and number of procedures for 65,032 patients listed as self-pay or free care, Blue Cross, or Medicaid at 52 hospitals in the Boston, Mass, area during 1983. We found that the overall case mix severity index (based on expected length of stay per diagnosis related group) for uninsured patients was 30% higher in public hospitals and 8% higher in major teaching hospitals compared with other institutions. Across all hospitals, the severity index of uninsured patients was similar to that of insured patients. However, after adjusting for diagnosis related group case mix, uninsured patients had, on average, 7% shorter stays (5.36 vs 5.79 days) and underwent 7% fewer procedures (1.16 vs 1.25) than Blue Cross patients, the differences varying with hospital type. Uninsured patients also had shorter stays on average than Medicaid patients (5.36 vs 5.87 days), but they underwent a similar number of procedures. These results suggest that patients who lack insurance may receive unequal treatment even after being hospitalized.

Risk factors of drug impairment in random samples of physicians and medical students

The prevalence of hypothesized risk factors of drug impairment is estimated and correlated with drug use in random samples of physicians and medical students. Substantial percentages of both physicians and medical students reported access to drugs, family histories of substance abuse, stress at work and home, emotional problems, and sensation seeking. Each of these factors correlated with drug use in physicians or medical students, and analysis suggested that in most cases the hypothesized risk factors were more likely to be causes rather than consequences of drug use.

Psychoactive drug use among practicing physicians and medical students

We surveyed random samples of 500 practicing physicians and 504 medical students in a New England state during 1984-1985; 70 percent of the physicians and 79 percent of the students responded. Fifty-nine percent of the physicians and 78 percent of the students reported that they had used psychoactive drugs at some time in their lives. In both groups, recreational use most often involved marijuana and cocaine, and self-treatment most often involved tranquilizers and opiates. In the previous year, 25 percent of the physicians had treated themselves with a psychoactive drug, and 10 percent had used one recreationally. Although most of the use was experimental or infrequent, 10 percent of the physicians reported current regular drug use (once a month or more often) and 3 percent had histories of drug dependence. More physicians and medical students had used psychoactive drugs at some time than had comparable samples of pharmacists and pharmacy students. The results suggest a need for renewed professional education about the risks of drug misuse.

Focal fatty liver lesions in alcoholic liver disease: a broadened spectrum of CT appearances

The CT examinations of 26 consecutive alcoholic patients with focal fatty infiltration of the liver were analyzed. Five different patterns of focal fatty infiltration were noted. In most alcoholic patients these appearances present no diagnostic problem and further confirmation can be obtained by repeating the CT scan within 1-2 weeks to see if interval resolution occurs following enforced abstinence. In select instances, more invasive and definitive procedures such as superselective angiography or liver biopsy may be necessary to differentiate these findings from other more serious diseases they may closely resemble, such as primary or secondary liver neoplasms.

Metabolism of the nigrostriatal toxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine by liver homogenate fractions

The metabolic fate of the nigrostriatal toxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) has been examined in rat and rabbit liver mitochondrial and rabbit liver microsomal preparations. The mitochondrial preparations rapidly oxidized MPTP, in a pargyline-sensitive reaction, to a polar material that was shown to contain the 1-methyl-4-phenylpyridinium species as the principal product. NADPH-supplemented microsomal preparations converted MPTP to two principal products: 4-phenyl-1,2,3,6-tetrahydropyridine and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine N-oxide. Carbon monoxide and SKF 525A selectively inhibited the oxidation of MPTP to the nor compound, indicating that this N-demethylation reaction is cytochrome P-450 catalyzed. Attempts to trap possible unstable iminium metabolites of MPTP in microsomal incubation mixtures with sodium cyanide led to the isolation of a monocyano adduct that proved to be the N-cyanomethyl derivative. Thus, hepatic mitochondrial and microsomal enzyme systems catalyze the oxidation of MPTP by different pathways, the former leading to the generation of species that may possess neurotoxic properties.

Hepatocellular carcinoma. Diagnostic and prognostic features in North American patients

Diagnostic and prognostic characteristics of 121 North American patients with hepatocellular carcinoma seen in one metropolitan area over a 6-year period were assessed using multivariate analysis. Presenting symptoms commonly included abdominal pain (53%) or mass (34%), anorexia (31%), and ascites (20%); however, the ability to make an early diagnosis was complicated by a variety of unusual symptoms accounting for 25% of presentations. While cirrhosis (63%) and hepatitis B surface antigen (HBsAg) positivity (52%) were common associated findings, the majority of patients (67%) had no prior diagnosis of liver disease. Despite the vascular nature of these malignancies, percutaneous biopsy procedures performed in 66 patients provided diagnostic material in over 85% of cases with little morbidity. Histologic diagnosis was made by blind percutaneous biopsy (41 done, 83% positive), peritoneoscopy with directed percutaneous biopsy (25 done, 88% positive), laparotomy (42 done, 98% positive), or autopsy (19). Percutaneous hepatic biopsy procedures were associated with no mortality and rare bleeding (three cases). Overall median survival was only 18 weeks; multivariate analysis indicated increased bilirubin or presence of pulmonary metastases adversely influenced outcome. Unexpectedly, patients younger than 45 years of age had a significantly (P less than 0.01) greater survival (median, 40 versus 9 weeks) than did older patients with this disease. We conclude: (1) hepatocellular carcinoma can be rapidly and safely diagnosed using percutaneous biopsy procedures; (2) North American patients with hepatocellular carcinoma younger than 45 years of age have a more favorable prognosis.

Hepatocellular carcinoma. Diagnostic and prognostic features in North American patients

Diagnostic and prognostic characteristics of 121 North American patients with hepatocellular carcinoma seen in one metropolitan area over a 6-year period were assessed using multivariate analysis. Presenting symptoms commonly included abdominal pain (53%) or mass (34%), anorexia (31%), and ascites (20%); however, the ability to make an early diagnosis was complicated by a variety of unusual symptoms accounting for 25% of presentations. While cirrhosis (63%) and hepatitis B surface antigen (HBsAg) positivity (52%) were common associated findings, the majority of patients (67%) had no prior diagnosis of liver disease. Despite the vascular nature of these malignancies, percutaneous biopsy procedures performed in 66 patients provided diagnostic material in over 85% of cases with little morbidity. Histologic diagnosis was made by blind percutaneous biopsy (41 done, 83% positive), peritoneoscopy with directed percutaneous biopsy (25 done, 88% positive), laparotomy (42 done, 98% positive), or autopsy (19). Percutaneous hepatic biopsy procedures were associated with no mortality and rare bleeding (three cases). Overall median survival was only 18 weeks; multivariate analysis indicated increased bilirubin or presence of pulmonary metastases adversely influenced outcome. Unexpectedly, patients younger than 45 years of age had a significantly (P less than 0.01) greater survival (median, 40 versus 9 weeks) than did older patients with this disease. We conclude: (1) hepatocellular carcinoma can be rapidly and safely diagnosed using percutaneous biopsy procedures; (2) North American patients with hepatocellular carcinoma younger than 45 years of age have a more favorable prognosis.

Metabolism-dependent inactivation of liver microsomal enzymes by phencyclidine

Incubation of phencyclidine (PCP) with rabbit liver microsomes resulted in NADPH-dependent loss of N-demethylase activity accompanied by reduction in microsomal cytochrome P-450 content. This effect was concentration-dependent, exhibited pseudo-first order kinetics, and was irreversible, thus exhibiting characteristics of "suicide substrate" inhibition. Cyanide ions at low concentrations, which have been used to trap the iminium intermediate of PCP metabolism as its cyano adduct, antagonized the inhibition of N-demethylase by PCP. PCP iminium ions were effective inhibitors of microsomal enzyme activity but required NADPH. These results support our suggestions that iminium ion formation is an intermediary step in the bioactivation of PCP leading to reactive electrophilic species.

Acute interstitial nephritis due to amoxicillin therapy

Acute interstitial nephritis (AIN) has been reported in association with therapy with a number of drugs. We report a patient who developed drug-related AIN while receiving intravenous amoxicillin therapy. The patient developed rash, secondary temperature elevation, and eosinophilia in association with nonoliguric renal failure. Renal biopsy showed evidence for AIN and the renal failure was responsive to corticosteroid therapy. AIN may occur in patients receiving any drug of the penicillin class. This reversible form of acute renal failure must not be overlooked in patients with other forms of renal disease.

Renal calcium binding protein in the diabetic and vitamin D-depleted rat

A calcium binding protein has been purified 220 fold from rat kidney. The molecular weight of this protein (26 000-28 000) is more than double that of the duodenal calcium binding protein of the rat. In response to the stimuli of both streptozotocin diabetes and depletion and repletion with vitamin D, changes in the renal protein are minimal. This contrasts markedly with responses of the duodenal protein to the same stimuli: (a) there was marked depression of duodenal calcium binding protein by vitamin D depletion and diabetes; (b) duodenal calcium binding protein was restored by vitamin D treatment of depleted rats. The renal protein appears to be identical with a previously described 28 000 molecular weight protein from the kidney purified by a different technique (Hermsdorf, C.L. and Bronner, F. (1975) Biochim. Biophys. Acta 379, 553-561). In contrast to findings of the current study, previous investigators were unable to isolate the protein from vitamin D-deficient rats and postulated vitamin D dependence. The protein activator of cyclic AMP phosphodiesterase is a calcium binding protein found in many tissues including kidney. Based on lack of response to stimuli we used and similarity in method of isolation and properties, our renal calcium binding protein may be this protein activator.