Production of a severe cystic fibrosis mutation in mice by gene targeting

We have used gene targeting in embryonic stem cells to introduce an HPRT mini-gene into the coding sequence of the murine cystic fibrosis gene (cftr). This insertion introduces a termination codon in frame with the cftr coding sequence to terminate prematurely the CFTR protein within the first nucleotide binding domain. Animals homozygous for the cftr disruption fail to thrive and display a range of symptoms including meconium ileus, distal intestinal obstructions, gastrointestinal mucus accumulation and blockage of pancreatic ducts. The animals also show lacrimal gland pathology. Tracheal and caecal transepithelial current measurements demonstrate the lack of a cAMP activatable Cl- channel. These animals will prove useful for the evaluation of new therapeutic drugs and gene therapy strategies.

Graphical analysis of MR feature space for measurement of CSF, gray-matter, and white-matter volumes

The problem of volume averaging in quantitating CSF, gray-matter, and white-matter fractions in the brain is solved using a three-compartment model and a simple graphical analysis of a multispectral MR feature space. Compartmentalization is achieved without the ambiguities of thresholding techniques or the need to assume that the underlying pixel probability distributions have a particular form. A 2D feature space is formed by double SE (proton density- and T2-weighted) MR data with image nonuniformity removed by a novel technique in which the brain itself serves as a uniformity reference. Compartments other than the basic three were rejected by the tailoring of limits in feature space. Phantom scans substantiate this approach, and the importance of the careful selection and standardization of pure tissue reference signals is demonstrated. Compartmental profiles from standardized subvolumes of three normal brains, based on a 3D (Talairach) coordinate system, demonstrate slice-by-slice detail; longitudinal studies confirm reproducibility. Compartmentalization may be described graphically and algebraically, complementing data displays in feature space and images of compartmentalized brain scans. These studies anticipate the application of our compartmentalization technique to patients with neurological disorders.

Hepatic perfusion changes in patients with liver metastases: comparison with those patients with cirrhosis

Previous studies using dynamic scintigraphy have shown that the measurement of changes in hepatic perfusion may be exploited to detect liver metastases. Similar hepatic haemodynamic changes also occur in cirrhosis, however, thereby reducing the diagnostic power of the technique. The ability of duplex colour Doppler sonography (DCDS) to differentiate between the changes in liver perfusion in patients with cirrhosis and those with hepatic metastases was assessed. Hepatic arterial and portal venous blood flows were measured in 30 control subjects, 20 patients with cirrhosis, and 55 patients with overt liver metastases. The Doppler perfusion index (DPI) (the rate of hepatic arterial to total liver blood flow) and the congestive index (ratio of the cross sectional area of the vessel to time averaged velocity of blood flow in the vessel) of the hepatic artery (HCI) and portal vein (PCI) were calculated. The hepatic arterial blood flow of the cirrhotic and metastatic groups was significantly raised compared with that of controls, and the portal venous blood flow of the former groups were reduced (p < 0.0001). The DPIs of the cirrhotic and metastatic groups were therefore significantly raised compared with those of controls (p < 0.0001). No significant difference was noted in HCI values between the three groups. The PCI values of the cirrhotic group, however, were significantly raised compared with those of controls and patients with metastases (p < 0.0001). The data suggest that DCDS measurement of PCI may be of value in differentiating between the hepatic perfusion changes caused by cirrhosis and those resulting from hepatic metastases, thereby increasing the diagnostic power of this technique.

Midwifery care for women with human immunodeficiency virus disease in pregnancy. A demonstration project at the Johns Hopkins Hospital

Nurse-midwives at the Johns Hopkins Hospital, in conjunction with their colleagues in obstetrics, pediatrics, and infectious disease, are participating in a demonstration project designed to provide continuity of care for women with HIV disease in pregnancy. In the past 19 months, 73 women have been enrolled in the project. This article describes how the midwifery model of care has been integrated into the existing system of routine obstetric care and specialized HIV-related care at the institution. This project could serve as a model for others who are redesigning health care delivery systems to include more nurse-midwives, especially those who are trying to adapt to an ever-increasing number of women experiencing some phase of HIV disease during their pregnancy. A companion article explains the midwifery and medical protocols used in the project and discusses other clinically relevant issues.

HIV-infected women and infants. Social and health factors impeding utilization of health care

The utilization of health care by HIV-seropositive pregnant women and their infants was studied in an indigent urban population. Ninety HIV-seropositive women delivered 99 HIV-exposed infants at the Johns Hopkins Hospital from August 1, 1988, to April 1, 1991. Repeat pregnancies occurred in 17 (18.9%) women during the study period. Completion of the primary immunization series by age nine months was the criteria for infant adherence to medical care. Of all infants, 72.9% achieved adequate immunization status by nine months. However, only 41 (45.6%) women reported ever seeking HIV-related health care. Factors associated with maternal adherence with HIV-related health care included HIV status of her infant, maternal drug use, and incarceration. Number of living children, maternal age, educational level, marital status, and repeat pregnancy were not associated with mothers seeking HIV-related health care. Despite low adherence to HIV-related health care in this sample of HIV-seropositive women, the majority of their infants did receive adequate immunizations, one proxy measure of adequate infant health care.

Nurse-midwifery management of women with human immunodeficiency virus disease

Primary care for women with human immunodeficiency virus (HIV) disease is appropriately provided by nurse-midwives within a well-coordinated system of medical consultation and referral. The issues of access to care, partner notification, reproductive choice, and breast-feeding are discussed. The nature of the collaborative management of HIV in pregnancy is explained. Management issues include the effects of HIV infection and pregnancy upon each other, perinatal transmission risks and postpartum needs, family planning, and gynecologic needs. Clinical care guidelines are included.

Etoposide in combination as first-line chemotherapy for advanced Hodgkin disease. A Cancer and Leukemia Group B study

BACKGROUND

In a pilot study, Cancer and Leukemia Group B (CALGB) incorporated etoposide into primary combination therapy for advanced Hodgkin disease.

METHODS

Thirty-six evaluable patients were treated with two or three courses of methotrexate, vincristine, prednisone, leucovorin, etoposide, and cyclophosphamide (MOPLEC), and then treated with five to seven additional courses of a known "curative" regimen: nitrogen mustard, vinblastine, prednisone, and procarbazine (MVPP).

RESULTS

After treatment with MOPLEC, there were 16 complete responders (44%) and 18 partial responders (50%). One patient had progressive disease and one patient was taken off study after an anaphylactic reaction to etoposide. After completing the entire protocol, 32 patients achieved complete remission (CR) (89%) and 3 achieved partial remission (PR) (8%). Five CR patients have relapsed and three additional patients have died in CR without recurrence. At 36 months, the estimated failure-free survival is 61% and overall survival is 72%.

CONCLUSIONS

This combination, which includes etoposide, is active for the primary treatment of advanced Hodgkin disease.

Clinical features and prognosis of follicular large-cell lymphoma: a report from the Nebraska Lymphoma Study Group

PURPOSE

Our purpose was to describe the treatment outcome of patients with follicular large-cell lymphoma (FLCL) and to identify prognostic factors that affect the treatment outcome.

PATIENTS AND METHODS

Between 1980 and 1991, 107 newly diagnosed, previously untreated patients with FLCL were prospectively treated using treatment plans of the Nebraska Lymphoma Study Group (NLSG). Most stage I/II patients received two to three cycles of one of four closely related six-drug combination chemotherapy regimens (cyclophosphamide, doxorubicin or mitoxantrone, and procarbazine, plus bleomycin, vincristine, and prednisone or dexamethasone [CAP/BOP I-IV]) plus involved-field radiotherapy; 10 patients received involved-field irradiation only. Stage III/IV patients received six to eight cycles of CAP/BOP.

RESULTS

Forty-four percent of patients had stage I/II disease. Stage I/II patients were older and more often female than stage III/IV patients. Cytogenetic studies were available on 35 patients: seven were normal; the most common abnormality was a translocation involving 14q32. Abnormalities of 1p or 1q were also common, often secondary to a 14q32 abnormality. The median follow-up of surviving patients is 2 years. The complete response rates observed were stage I/II, 88%; stage III/IV, 49%. Complete response rates were affected by both age and tumor bulk. Failure-free survival (FFS; time to first occurrence of progression, relapse after response, or death from any cause) at 3 years was estimated to be 61% for stage I/II patients and 34% for stage III/IV patients. Survival at 3 years was estimated to be 76% and 61%, respectively. FFS of stage III/IV patients was poorer for stage IV patients and those with composite lymphomas. Significantly poorer survival was only seen in patients older than 70 years of age.

CONCLUSION

A proportion of stage I/II FLCL patients may obtain long-term disease control with combination chemotherapy plus radiotherapy. Results for patients with stage III/IV FLCL are similar to those seen for other follicular lymphomas.

AMOPLACE treatment of intermediate-grade and high-grade malignant lymphoma: a Cancer and Leukemia Group B study

PURPOSE

In an attempt to improve the efficacy of cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) chemotherapy for intermediate-grade and high-grade non-Hodgkin's lymphomas, a phase II evaluation of a regimen consisting of Adriamycin (doxorubicin; Adria Laboratories, Columbus, OH), methotrexate, Oncovin (vincristine; Eli Lilly Co, Indianapolis, IN), prednisone, leucovorin, cytarabine (ara-c), cyclophosphamide, and etoposide (AMOPLACE) was conducted. This regimen includes three additional agents not found in CHOP, uses weekly doses of alternating myelosuppressive and nonmyelosuppressive drugs, and incorporates most single agents active against diffuse lymphomas.

PATIENTS AND METHODS

Ninety-one previously untreated patients were enrolled and 60 patients were confirmed eligible after central pathology review. Fifty-eight percent of patients had diffuse large-cell lymphoma (DLCL), 83% had stage III or IV disease, and 45% had B symptoms.

RESULTS

Patients were treated with six to eight cycles of AMOPLACE and analyzed for response and survival. With a median follow-up of 48 months, complete responses (CRs) were seen in 68% of all patients with failure-free survival (FFS) and overall survival (OS) estimates at 4 years of 45% and 54%. In the DLCL subset, the CR rate was 69% and FFS and OS estimates at 4 years were 49% and 60%, respectively. The major toxicity was myelosuppression, with 73% of patients having WBC nadirs less than 1,000/microL; two treatment-related deaths occurred.

CONCLUSION

We conclude that AMOPLACE is associated with CR and OS rates comparable with those of other third-generation regimens.

Adolescents and human immunodeficiency virus infection

As of March 31, 1992, individuals 13 to 19 years of age had been diagnosed with acquired immunodeficiency syndrome; over one third were diagnosed in the past 2 years alone. Because of the long incubation period from initial infection to acquired immunodeficiency syndrome diagnosis, the majority of young adults with acquired immunodeficiency syndrome were probably initially infected as adolescents. In 1991, 34% of adolescents with acquired immunodeficiency syndrome were female, and their predominant mode of transmission was heterosexual contact. Human immunodeficiency virus seroprevalence studies of adolescents show a male-to-female ratio approaching 1:1, with many human immunodeficiency virus-infected adolescent women identifying none of the standard risk. Factors such as sexual and drug experimentation, risk taking, and sense of invulnerability so characteristic of adolescence put adolescents at special risk for human immunodeficiency virus. There is no published information on if or how clinical manifestations of human immunodeficiency virus disease in adolescents might differ from those seen in adults. Medical care should be broad-based and should include access to clinical trials for new drug treatments. General knowledge levels about acquired immunodeficiency syndrome are high among US adolescents, but behavioral changes have lagged behind. All adolescents should be targeted for intensive education about human immunodeficiency virus along with interventions designed to enhance their general coping, communication, and decision-making skills.

Bone marrow transplantation for peripheral T-cell lymphoma in children and adolescents

We report nine children with relapsed (n = 8) or high-risk (n = 1) peripheral T-cell lymphoma (PTCL) who underwent autologous (n = 6) or allogeneic (n = 3) bone marrow transplantation (BMT). These children received transplants as part of a prospective phase I/II study of thioTEPA (TT) and total body irradiation (TBI) with escalating doses of VP-16. The median age of these patients at time of BMT was 6.5 years (range 2.5 years to 14 years). Three were transplanted with active disease after failing salvage chemotherapy. Of the other six, one was transplanted in first complete remission (CR) and five in second or subsequent CR. Of these nine patients, eight are free of disease a median of 25 months after BMT (range, 6 to 48 months), with an estimated 2-year relapse-free survival (RFS) of 89%. Six of these eight patients have been followed for 12 or more months after BMT, and in each their current remission exceeds their longest previous remission duration. The toxicity of the TT/TBI +/- VP-16 regimens was significant but manageable, predominantly consisting of severe mucositis. For a comparison, we reviewed retrospective data on the six additional children and adolescents with PTCL who underwent BMT during the 3-year period preceding this phase I/II study. The median age at BMT of these six patients was 19 years (range 15.5 years to 20 years). These patients were prepared for BMT with a variety of other regimens. One had no response to BMT and the other five relapsed at 1.5 to 5 months after BMT (median, 3 months) with an RFS of 0%. Our data suggest that thioTEPA plus TBI, with or without VP-16, is an effective preparative regimen for BMT for young patients with relapsed or high-stage PTCL and leads to prolonged RFS.

Chemotherapy of advanced Hodgkin's disease with MOPP, ABVD, or MOPP alternating with ABVD

BACKGROUND AND METHODS

MOPP (mechlorethamine, vincristine, procarbazine, and prednisone) has been the standard treatment for Hodgkin's disease for almost 20 years. In a randomized, multicenter trial, we compared three regimens of primary systemic therapy for newly diagnosed advanced Hodgkin's disease in Stages IIIA2, IIIB, and IVA or IVB: (1) MOPP alone given for 6 to 8 cycles, (2) MOPP alternating with ABVD (doxorubicin, bleomycin, vinblastine, and dacarbazine) for 12 cycles, and (3) ABVD alone for 6 to 8 cycles. Patients in a first relapse after radiation therapy were eligible. No additional radiation therapy was given. Patients who did not have a complete response or who had a relapse with either MOPP alone or ABVD alone were switched to the opposite regimen.

RESULTS

Of 361 eligible patients, 123 received MOPP, 123 received MOPP alternating with ABVD, and 115 received ABVD alone. The patients were stratified according to age, stage, previous radiation, histologic features, and performance status. The overall response rate was 93 percent, with complete responses in 77 percent: 67 percent in the MOPP group, 82 percent in the ABVD group, and 83 percent in the MOPP-ABVD group (P = 0.006 for the comparison of MOPP with the other two regimens, both of which contained doxorubicin). The rates of failure-free survival at five years were 50 percent for MOPP, 61 percent for ABVD, and 65 percent for MOPP-ABVD. Age, stage (III vs. IV), and regimen influenced failure-free survival significantly. Overall survival at five years was 66 percent for MOPP, 73 percent for ABVD, and 75 percent for MOPP-ABVD (P = 0.28 for the comparison of MOPP with the doxorubicin regimens). MOPP had more severe toxic effects on bone marrow than ABVD and was associated with greater reductions in the prescribed dose.

CONCLUSIONS

In this trial, ABVD therapy for 6 to 8 months was as effective as 12 months of MOPP alternating with ABVD, and both were superior to MOPP alone in the treatment of advanced Hodgkin's disease. ABVD was less myelotoxic than MOPP or ABVD alternating with MOPP.

Laser recanalization versus endoscopic intubation in the palliation of malignant dysphagia: a randomized prospective study

Forty patients with histologically confirmed malignant dysphagia were randomized to either endoscopic intubation or laser recanalization. Age, sex, tumour histology and site were evenly distributed between the groups. Results were analysed on an 'intention to treat' basis. All patients treated by laser achieved patency; there was one failed intubation. The best swallowing grade achieved was significantly better with laser recanalization (median 4 (range 3-4)) than with intubation (median 3 (range 2-4)) (P < 0.001). The median survival was 21.5 (range 4-62) weeks in the group receiving laser treatment, compared with 14.5 (range 7-102) weeks in the intubated group (P = 0.09). The median inpatient stay as a proportion of survival time was 14 per cent in the group receiving laser treatment compared with 15 per cent in the intubated group (P > 0.05). The median weight loss was less in the laser-treated patients (2.0 (range 2-8) versus 3.0 (range 0-10) kg, P = 0.04). These results indicate that laser recanalization provides better palliation of dysphagia than does intubation, but this is not reflected in an improvement in survival time.

A prospective trial of endoscopic sclerotherapy v oesophageal transection and gastric devascularisation in the long term management of bleeding oesophageal varices

In a prospective three centre study oesophageal transection and gastric devascularisation have been compared with endoscopic sclerotherapy in the long term management of bleeding oesophageal varices. Cirrhotic patients (Child's A or B grade) with documented bleeding oesophageal varices were treated initially with emergency sclerotherapy, and after five days stability, were allocated to one of the two treatment regimes. The endoscopic sclerotherapy group underwent regular sclerotherapy until variceal obliteration while those undergoing surgery were not endoscoped unless bleeding recurred, when they were treated by sclerotherapy if appropriate. Ninety two patients were eligible for analysis (68% alcoholic cirrhosis; mean age 50.1 years) and follow up was achieved for a mean of 52.5 months (range 17-83). Mortality in the first three months was greater in the oesophageal transection and gastric devascularisation group (20% v 1%) but by two years the survival curves were the same and thereafter there was no difference in mortality. Rebleeding occurred in 13/41 (31%) patients, undergoing oesophageal transection and gastric devascularisation. The costs incurred during the first year of oesophageal transection and gastric devascularisation treatment were significantly greater than with endoscopic sclerotherapy (4369 pounds v 1067 pounds, p < 0.0001) and the high rate of rebleeding in the surgical group meant that no cost savings occurred in subsequent years. It is concluded that oesophageal transection and gastric devascularisation confers no benefit over endoscopic sclerotherapy in terms of long term survival and that it is not cost effective as judged by the current health care costs in the United Kingdom.

Self-recognition in Alzheimer's disease: a mirror and video study

Twenty-nine subjects with Senile Dementia of the Alzheimer Type (SDAT) were tested for self-recognition when confronted with their reflection in a mirror and with a noncontingent video image. All subjects at stage 5 (moderately severe cognitive decline) on the Global Deterioration Scale (GDS) showed self-recognition in the mirror condition, whereas 25% of GDS stage 6 subjects (severe cognitive decline) did not self-recognize. Only seven subjects showed signs of self-recognition on video (six at GDS 5, one at GDS 6). The results confirm two hypotheses: the first, based on studies with infants, is that contingency cues in the mirror condition facilitate self-recognition; the second is that SDAT patients may show "regression" of at least some cognitive functions.

Progressive disease after high-dose therapy and autologous transplantation for lymphoid malignancy: clinical course and patient follow-up

Of 364 patients with lymphoid malignancy who underwent high-dose therapy with autologous bone marrow transplantation (ABMT) or peripheral stem cell transplantation (PSCT), 169 patients have had progressive disease after the procedure. The median survival from the time of relapse for patients with Hodgkin's disease (HD) who progressed after the transplant was 10.5 months. This compares with a median survival of 3 months for relapsed non-Hodgkin's lymphoma (NHL) patients (P = .0036). After failing transplantation, 56 patients were treated with further chemotherapy, 35 with involved field irradiation therapy, and 18 patients were treated with combination chemotherapy and irradiation. Seven patients received biologic therapy and seven patients underwent a second bone marrow transplant. The remainder of the patients were believed to be too ill for further therapy or chose not to receive further treatment for their recurrent lymphoid malignancy. Sixty of the 169 patients with progressive disease after the transplant are still alive; however, only 18 patients are alive off therapy without evidence of active disease after their relapse. Ten of the 18 patients are still less than 12 months past their posttransplant salvage therapy and are at high-risk for relapse. Five patients are progression free at 15 to 36 months after their posttransplant relapse. Only three patients (two NHL and one HD) treated with other modalities after autologous transplant failure are alive without evidence of disease and have been observed at least 4 years postrelapse. Although a few patients will have a durable response to subsequent therapy, the majority of patients who have progressive disease after an autologous transplant for lymphoid malignancy will succumb to recurrent disease within a short period of time.

A phase II study of recombinant interleukin-2 with or without recombinant interferon-beta in non-Hodgkin's lymphoma. A study of the Cancer and Leukemia Group B

Interleukin-2 (IL-2) and interferon-beta (IFN-beta) have demonstrated activity against lymphoid malignancies, presumably mediated by the augmentation of lymphokine-activated killer (LAK) cell and natural killer (NK) cell activity. There is in vitro and in vivo evidence to suggest that the combination of IL-2 and IFN-beta is synergistic. The Cancer and Leukemia Group B (CALGB) conducted a randomized phase II trial of IL-2 with or without IFN-beta in 49 patients with relapsed or refractory non-Hodgkin's lymphoma (NHL). Overall toxicity was severe, with 17 patients experiencing life-threatening toxicity. Three patients had treatment-related deaths. Responses were noted in seven patients (17%). There were no meaningful differences between treatment arms in toxicity profile, response rate, or modulation of in vivo NK and LAK activity. We conclude that IL-2 with or without IFN-beta is not effective therapy for NHL in the doses and schedule used in this study.

Airway inflammation predicts diffuse alveolar hemorrhage during bone marrow transplantation in patients with Hodgkin disease

We determined risk factors present in patients with Hodgkin disease that predicted the development of diffuse alveolar hemorrhage syndrome (DAH) during autologous bone marrow transplantation (BMT). One hundred twenty-three patients with Hodgkin disease prospectively underwent bronchoscopy with bronchoalveolar lavage (BAL) before receiving BMT. The bronchitis index (BI) of the airways and bronchial and alveolar cell counts and differentials were determined in all patients and compared with 20 normal nonsmoking volunteers. Logistic regression analysis was used to determine factors that predicted for the development of DAH. Visual evidence of bronchial injury was observed regardless of smoking history (BI = 7.8 +/- 0.5 for BMT versus 2.3 +/- 0.5 for volunteers, p = 0.001). BMT patients who developed DAH (n = 14) had significantly greater numbers of bronchial neutrophils and eosinophils compared with DAH-negative (n = 109) patients (bronchial polymorphonuclear leukocytes (PMN), 33 +/- 7% versus 14 +/- 2%, p = 0.006; bronchial eosinophils, 0.9 +/- 0.3% versus 0.4% +/- 0.07%, p = 0.02). Logistic regression analysis revealed that the presence of bronchial PMN > 20% or bronchial eosinophils > zero% were predictive of DAH (p = 0.005 and 0.05, respectively). When both predictors were positive, the rate of DAH was 10 times greater than when both predictors were negative (43% versus 4% DAH occurrence). Survival was also significantly reduced when these predictors were positive. This study demonstrates that bronchial inflammation is present with or without intraluminal inflammatory cells in the majority of patients with Hodgkin disease before BMT. The subgroup of these patients with increased bronchial inflammatory cells are at greatly increased risk for development of DAH and death.

Continuous coeliac plexus blockade plus intermittent wound infiltration with bupivacaine following upper abdominal surgery: a double-blind randomised study

In this double-blind trial, we observed the effect of intermittent wound infiltration with local anaesthetic plus continuous coeliac plexus blockade on postoperative pain relief, pulmonary function, the neuroendocrine and acute phase protein response following upper abdominal surgery. In Group A (n = 10) patients received bupivacaine intermittently into the wound and continuously into the coeliac plexus following an initial bolus. A total of 862.5 mg of bupivacaine was used over 12 h with no observed toxicity. Group B (n = 10) received equal volumes of saline. Although pain relief was poor in both groups, the bupivacaine group used less morphine postoperatively and had lower pain scores than the saline group 4 h after operation (P less than 0.05). Pulmonary function was significantly reduced in both groups with no statistical difference between the two. Significant reductions in serum glucose and cortisol were achieved (P less than 0.05), suggesting that afferent neural blockade was partially effective in attenuating the neuroendocrine response. However, the postoperative rise in interleukin-6 was not affected by this technique. It is concluded that total afferent neural blockade cannot be achieved with peripheral wound and coeliac plexus administration of relatively large doses of local anaesthetic during upper abdominal surgery.

Predicting genitourinary toxicity in patients receiving cisplatin-based combination chemotherapy: a Cancer and Leukemia Group B study

Assessment of renal function prior to cisplatin chemotherapy has long been based on measurement of creatinine clearance by 24-hour urine collection (CrCmeas). Estimated creatinine clearance (CrCest) as calculated from the patient's age, weight, and serum creatinine level has been suggested as an adequate surrogate for CrCmeas, as it provides advantages of improved convenience, decreased cost, and possibly increased accuracy. We studied 847 patients receiving cisplatin-based chemotherapy on Cancer and Leukemia Group B (CALGB) protocols to determine whether the CrCmeas, CrCest, or serum creatinine value or the age of the patient would predict the subsequent genitourinary (GU) toxicity. Both CrCmeas (P = 0.001) and CrCest (P = 0.02) were predictive of subsequent grade 2+ GU toxicity, with CrCmeas being a slightly better predictor. Patient age also influenced subsequent GU toxicity, with the risk increasing with age (P = 0.0008). When patients were classified by age group and by CrCmeas, distinct subgroups were identified, with differences in the risk for grade 2+ GU toxicity ranging from 14% to 32%. Using a logistic model to assess the probability of grade 2+ GU toxicity, we found that an age of greater than or equal to 60 years (P = 0.005), a CrCmeas value of less than 75 ml/min (P = 0.004), and the risk characteristics of the individual cisplatin trial were important, whereas CrCest was not. Furthermore, CrCest proved to be a poor predictor of a CrCmeas value of less than 75 ml/min, "misclassifying" nearly half of the patients to a "lower-risk" subgroup. In summary, both CrCmeas and the patient's age independently provided predictive information concerning cisplatin GU toxicity. Our data support the continued clinical usefulness of determining the CrCmeas value prior to the administration of cisplatin-based chemotherapy to most patients.

Development of self-recognition in chimpanzees (Pan troglodytes)

Chimpanzees (Pan troglodytes) demonstrate the ability to recognize themselves in mirrors, yet investigations of the development of self-recognition in chimpanzees are sparse. Twelve young chimpanzees, grouped by age, were given mirror exposure and tested for self-recognition and contingent movement. All 6 juveniles, 4 and 5 years old, exhibited mirror-guided, mark-directed behavior and clear evidence of self-recognition. In contrast, among the infants, only the oldest group of 2 1/2-year-olds exhibited clear evidence of self-recognition. All chimpanzees exhibited both self-directed behaviors and contingent movements. These results suggest that self-recognition occurs at a slightly older age in chimpanzees than in human infants. In humans, self-recognition is linked with other cognitive abilities. The results conform to the general pattern that great apes exhibit many cognitive skills comparable to those of 2-year-old humans.