Specific organ gene transfer in vivo by regional organ perfusion with herpes viral amplicon vectors: implications for local gene therapy

BACKGROUND

Many gene therapy strategies would benefit from efficient, regional organ delivery of therapeutic genes.

METHODS

Regional perfusions of lung, liver, or bladder were performed to determine if rapid and efficient gene transfer can be accomplished in vivo, and to determine if in vivo gene transfer can be limited to the organ of interest. In addition, herpes simplex virus tumor necrosis factor (HSVtnf), carrying the human tumor necrosis factoralpha gene was used as a treatment for methylcholanthrene sarcoma in a syngeneic lung metastases model in Fisher rats.

RESULTS

A 20-minute perfusion using HSV carrying beta-galactosidase (HSVlac) produced significant expression of this marker gene isolated to the target organs, without organ-specific tissue injury or inflammation. Regional perfusion of organs with HSV carrying the cytokine gene tumor necrosis factor alpha also resulted in high-level local organ production of this cytokine (2851 +/- 53 pg/g tissue in perfused lung versus 0 for the contralateral lung). For the current vector construct, expression of the gene of interest peaked between 2 and 4 days and was undetectable by 2 weeks after perfusion. In animals undergoing perfusion as treatment for pulmonary sarcoma, there was no difference between tumor counts in lungs perfused with HSVlac (17 +/- 6) or HSVtnf (22 +/- 8), but either treatment resulted in lower tumor counts than controls (111 +/- 24 nodules per lung, P <.02).

CONCLUSIONS

Regional organ perfusion using herpes viral vectors is an effective and well-tolerated in vivo method of transiently delivering potentially toxic gene products to target organs in directing gene therapy. Regional lung perfusion with HSV amplicons reduces tumor burden in a rat model of pulmonary metastases, though HSVtnf cannot be demonstrated to augment the cytopathic effect of the HSV amplicon alone in the current model.

Regulation of DNA-dependent protein kinase activity by ionizing radiation-activated abl kinase is an ATM-dependent process

Ionizing radiation (IR) treatment results in activation of the nonreceptor tyrosine kinase c-Abl because of phosphorylation by ATM. In vitro evidence indicates that DNA-dependent protein kinase (DNA-PK) can also phosphorylate and thus potentially activate Abl kinase activity in response to IR exposure. To unravel the role of ATM and DNA-PK in the activation of Abl, we assayed Abl, ATM, and DNA-PK activity in ATM- and DNA-PKcs-deficient cells after irradiation. Our results show that despite the presence of higher than normal levels of DNA-PK kinase activity, c-Abl fails to become activated after IR exposure in ATM-deficient cells. Conversely, normal activation of both ATM and c-Abl occurs in DNA-PKcs-deficient cells, indicating that ATM but not DNA-PK is required for activation of Abl in response to IR treatment. Moreover, activation of Abl kinase activity by IR correlates well with activation of ATM activity in all phases of the cell cycle. These results indicate that ATM is primarily responsible for activation of Abl in response to IR exposure in a cell cycle-independent fashion. Examination of DNA-PK activity in response to IR treatment in Abl-deficient cells expressing mutant forms of Abl or in normal cells exposed to an inhibitor of Abl suggests an in vivo role for Abl in the down-regulation of DNA-PK activity. Collectively, these results suggest a convergence of the ATM and DNA-PK pathways in the cellular response to IR through c-Abl kinase.

Acoustic rhinometry and computed tomography scans for the diagnosis of nasal septal deviation, with clinical correlation

OBJECTIVE

The aim in this study was to analyze the efficiency and reliability of acoustic rhinometry (AR) readings in recognition of nasal septal deviation.

METHOD

We compared 24 patients' AR readings with their sinus CT scans. The patient data were analyzed by comparison with normative data, area, and percentage differences between the two sides. Additionally, the data further analyzed by receiver operating characteristic curve and Spearman correlation of CT and AR in determining nasal septal deviation.

RESULTS

The sensitivity of AR in detecting anterior septal deviations was found to be 54%, with a specificity of 70%. A very highly significant correlation (P < or = 0.001) was found between minimal cross-sectional area (CSA) 1 values and CT results.

DISCUSSION

In the interpretation of AR readings, comparison of each CSA value should be included, in addition to use of the total absolute CSA values.

CONCLUSION

According to our findings the diagnosis of nasal septal deviation can be supported by AR readings.

Loratadine/pseudoephedrine for nasal symptoms in seasonal allergic rhinitis: a double-blind, placebo-controlled study

In this double-blind, placebo-controlled, crossover, parallel study, we treated 20 adults who had seasonal allergic rhinitis with once-daily fixed-combination loratadine/pseudoephedrine sulfate to observe its effect on relieving symptoms, primarily nasal congestion. Acoustic rhinometry detected a trend toward improvement in nasal patency, although the difference between pre- and post-treatment measures was not statistically significant. Endoscopic inferior turbinate photography documented that treatment led to statistically significant reductions in the amount of nasal edema and nasal secretions. The results of a quality-of-life questionnaire suggested that treatment alleviated nasal and ocular symptoms of rhinoconjunctivitis. An analysis of subjective visual analog scale scores showed a trend toward improvement in most but not all nasal symptoms. We conclude that once-a-day fixed-combination loratadine/pseudoephedrine is effective in relieving nasal congestion in patients with seasonal allergic rhinitis.

Predictors of post-hospital employment status for psychiatric patients in Hong Kong: from perceptions of rehabilitation professionals to empirical evidence

Fifty participants with mental illness and a concrete discharge plan were selected from two mental hospitals in Hong Kong and assessed on their Psychosocial support by the Chinese Version of the Significant Others Scale, social vocational competence using the Workshop Behavior Checklist and the Vocational Social Skills Scale, medical history, work history, and demographic variables. At three months after discharge, the employed participants (n = 12) were shown to have better psychosocial support and social vocational competence than the unemployed participants (n = 24) by univariate comparison. The employed and unemployed participants did not differ in their medical and work history, and demographic variables. Implications of the results for rehabilitation programming are discussed.

Cardiac operations in patients with low-grade small lymphocytic malignancies

BACKGROUND

Low-grade small lymphocytic (B cell) malignancies (encompassing chronic lymphocytic leukemia and some types of non-Hodgkin lymphoma) are diseases of the elderly. Open cardiac procedures are known to have increased risk of postoperative infection and other morbidities in these immunodeficient patients. Outcome of open cardiac procedures in these patients was reviewed retrospectively.

PATIENTS

Thirteen patients (aged 58-82 years, 11 men, 2 women) with these lymphocytopathologic diseases (8 with chronic lymphocytic leukemia and 5 with non-Hodgkin lymphoma) underwent cardiac operations between January 1977 and June 1998. Mean age was 72 +/- 2.1 years. Isolated coronary artery bypass grafting was performed in 11 and combined procedures and double valve replacement were performed in 1 each. Preoperatively, 9 patients were in a low-risk clinical stage. Mean preoperative duration of lymphocytopathologic disease was 6.1 +/- 1.6 years. Mean preoperative New York Heart Association functional class was 2.8.

RESULTS

There was no operative death. Average stay in the intensive care unit was 41.4 +/- 8.6 hours. Postoperative leg and superficial sternal wound infections were encountered in 3 patients. Average postoperative hospital stay was 10.0 +/- 1.7 days. During the follow-up up to 72 months, 1 patient underwent a second cardiac operation. There was 1 late death 4 years later. Coronary stenting was done in 1 patient and a cardioverter-defibrillator was implanted in another patient for recurrent angina. Three patients underwent chemotherapy. Cardiac and lymphocytopathologic status remained stable in others.

CONCLUSIONS

Acceptable outcome may be anticipated after cardiac operations in patients with low-grade chronic lymphocytic leukemia and non-Hodgkin lymphoma in early stages. However, the possibility of infection and progression of cardiac and lymphocytopathologic status in these patients should call for caution.

An audit of pancreatic pseudocyst management and the role of endoscopic pancreatography

BACKGROUND

A rational algorithm for the management of symptomatic pancreatic pseudocysts is necessary with the increasing availability of radiological, surgical and endoscopic methods of treatment.

METHODS

A retrospective audit of the management and outcome of all patients who presented with symptomatic pancreatic pseudocysts to the Auckland Hospital over a 9-year period (1988-96) was made.

RESULTS

There were 44 patients (28 men, 16 women; median age 50; range 18-81) in this series. Initial management was not based on pseudocyst size, duration, location, wall thickness, the patients' symptoms and comorbidity, or the aetiology of pancreatitis. Of the 27 patients who had initial conservative management, 15 pseudocysts (56%) completely resolved. Of the 17 patients who were initially or subsequently treated with percutaneous catheter drainage (PCD), 10 pseudocysts (59%) completely resolved without additional treatment. Of the 13 patients initially or subsequently treated by surgery, all but one completely resolved after the first procedure. Two patients were successfully treated with endoscopic pancreatic stent placement. Complications arose in eight patients treated with PCD (47%) and four patients treated with surgery (31%). There was no mortality. The decision for active treatment was not preceded by delineation of the pancreatic duct by ERCP (endoscopic retrograde cholangiopancreatography) in 60% of patients.

CONCLUSIONS

More than one-third of all patients with symptomatic pancreatic pseudocysts can be managed conservatively. Surgery yields excellent results but PCD has a high failure rate in patients with an underlying pancreatic duct stricture. A rational management algorithm is presented, based on pre-intervention ERCP, which should improve patient selection and outcome.

Nightguard vital bleaching: a review and clinical study

Based on current clinical experience and research, dentist-prescribed home bleaching, also referred to as nightguard vital bleaching, is a safe and effective technique for whitening teeth when a carbamide peroxide material (up to 10 percent) is used. The bleaching material should be produced by a recognised and reputable manufacturer and must be used under a dentist's supervision over a relatively short time. Mild thermal sensitivity is a common side effect; however, no long-term pulpal effects have been shown. The reduction in the bond strength of resin to freshly bleached enamel and dentine has been shown to be transient, and no clinically significant changes in surface morphology or physical properties have been shown to occur to teeth or dental restorative materials as a result of vital bleaching. As a consequence, vital bleaching has gained favour with patients and dentists alike. Significant benefit was obtained in 12 subjects using two nightguard bleaching systems which were equally effective.

Partial hepatectomy accelerates local tumor growth: potential roles of local cytokine activation

BACKGROUND

Surgical excision of liver tumors represents the only curative treatment for primary and metastatic liver malignancies. It has been suspected that hepatectomy may stimulate growth of microscopic tumors. To determine whether local or systemic factors after hepatectomy are responsible for enhancement of tumor growth, the effects of hepatectomy on the experimental growth of liver or pulmonary tumors were examined.

METHODS

One hour after injection of 10(6) Morris hepatoma cells into either the portal or femoral vein, which produces isolated liver and lung tumors, respectively, animals were randomized to undergo 0%, 30%, or 70% partial hepatectomy (PH).

RESULTS

Animals that underwent portal injection of tumor had significantly increased liver tumor burden after PH (sham, 25 +/- 7 vs PH, 94 +/- 17; p < 0.01), whereas animals that underwent femoral injection had no change in lung tumor burden after PH. PH was associated with significantly increased levels of transforming growth factor-alpha, transforming growth factor-beta, and basic fibroblast growth factor in the liver but not in the lung.

CONCLUSIONS

Changes in liver cytokine-growth factor activation may contribute to enhanced tumor growth in the liver after hepatectomy.

Establishment of an experimental intrapulmonary tumor nodule model

BACKGROUND

A pulmonary tumor model is necessary to study the biology and therapy of lung cancer. Methods to establish a solitary intrapulmonary nodule are not well defined. Two methods for solitary intrapulmonary tumor nodule development in the Fischer rat are described.

METHODS

Methylcholanthrene-induced sarcoma cell suspensions were introduced into lung parenchyma of Fischer rats via limited thoracotomy and lung puncture, or instilled into a distal airway after tracheal puncture and catheterization. Intrapulmonary tumor location, implantation mortality, procedure length, and animal survival were recorded.

RESULTS

Single pulmonary nodules developed at the implanted position in 100% (n = 320) and 95% (62/65) of animals after direct injection into the pulmonary parenchyma or via tracheal puncture and instillation. Operative mortality was 2% and 5% via lung or tracheal implantation, respectively. Less than 5 minutes was required for each implantation. Mean survival time was 24 +/- 2 and 26 +/- 6 days after lung or tracheal implantation in animals allowed to survive until tumor-induced death.

CONCLUSIONS

These easily performed, reproducible methods of establishing solitary intrapulmonary tumors are useful tools for lung cancer research.

Hypereosinophilic syndrome and myocardial infarction in a 15-year-old

The hypereosinophilic syndrome (HES) is a rare yet frequently fatal disorder of unknown etiology characterized by markedly elevated eosinophil counts and subsequent multiple organ failure due presumably to eosinophil-derived protein toxicity. We describe the laboratory and anatomic findings in a 15-year-old female with extraordinarily high circulating levels of eosinophil major basic protein (MBP) who sustained a precipitous cardiac death secondary to a massive myocardial infarction. Postmortem examination showed marked cardiomegaly with extensive recent left ventricular infarction. Occlusive thrombosis of small blood vessels was evident in the myocardium, spleen, lungs, and kidneys. Immunofluorescent staining showed massive MBP deposition in multiple organ parenchyma including the heart, renal glomeruli, adrenal cortex, bronchioles, and other visceral organs, suggesting a causal relationship. We hypothesize on the mechanisms of eosinophil toxicity in HES.

Regional chemotherapy via pulmonary artery with blood flow occlusion in a solitary tumor nodule model

This study is to evaluate low dose doxorubicin pulmonary artery perfusion with blood flow occlusion compared to systemic administration in a model of solitary intrapulmonary sarcoma nodule in the rat. Tumor nodule was developed via injection of methylcholanthrene-induced sarcoma into the left lung. Doxorubicin was perfused into the left pulmonary artery at a rate of 50 microliters/min for 2 min with 20 min blood flow blockage in all experiments. Pharmacokinetics, toxicity, treatment efficacy were compared between lung perfusion groups and intravenous groups. Doxorubicin levels in tumor, left lung, right lung, heart and serum were measured. Animal daily weights were recorded and a right pneumonectomy was performed following treatment to assess toxicity and tolerated perfusion dose. Tumors were weighed following treatment to evaluate treatment efficacy. Doxorubicin delivered via pulmonary artery caused a significant higher drug level in tumor tissue and perfused lung with a low drug level in heart, right lung and serum as compared to intravenous administration. Animals in perfusion groups had normal growth pattern and survived after pneumonectomy when a dose of 0.5 mg/kg doxorubicin was perfused. Tumor weight was significantly decreased after treated with 0.5 mg/kg of doxorubicin lung perfusion as compared to same dose of doxorubicin intravenous treatment. Pulmonary artery perfusion with blood flow occlusion may offer an effective lung chemotherapeutic model. 0.5 mg/kg doxorubicin for lung perfusion has acceptable local lung toxicity and no significant systemic toxicity and is pharmacokinetically and therapeutically superior to systemic administration in this solitary intrapulmonary tumor nodule model in the rat.

Isolated lung perfusion with FUDR in the rat: pharmacokinetics and survival

BACKGROUND

Although surgical resection remains the mainstay of treatment for metastatic pulmonary colorectal cancer, 5-year survival approaches only 30% to 40%. We have developed a model of isolated left lung perfusion (ILP) with FUDR (2'-deoxy-5-fluorouridine) for the treatment of pulmonary colorectal metastases. FUDR ILP toxicity and pharmacokinetics were evaluated and compared with continuous intravenous infusion in the rat.

METHODS

Toxicity was first evaluated in F344 rats (n = 17) after left ILP (20-minute perfusion at 0.5 mL/min) with 21 mg/mL (n = 11), 28 mg/mL (n = 2), 35 mg/mL (n = 2), and 70 mg/mL (n = 2) of FUDR. Animals were followed up and weights recorded for 14 days postoperatively before a right pneumonectomy was performed to evaluate the effect of FUDR perfusion on left lung function. In the second study, 32 rats (n = 8/group) underwent: systemic FUDR (intravenous), or ILP with 7, 14, and 21 mg/mL respectively (ILP 7, ILP 14, and ILP 21 groups). Left lungs and serum were analyzed for FUDR and 5-fluorouracil by high-performance liquid chromatography.

RESULTS

Rats perfused with doses of FUDR greater than 21 mg/mL died perioperatively. All animals perfused at 21 mg/mL survived until day 14, and 8/11 survived a right pneumonectomy. Rats that survived ILP resumed normal weight gain and grooming habits within 1 week. Pharmacokinetic evaluation demonstrated that ILP at 21 mg/mL maximally elevated total lung FUDR and 5-fluorouracil levels (508.5 +/- 96.4 micrograms/g lung) in comparison with the ILP 14, ILP 7, and intravenous groups (299.1 +/- 44.8, 116.0 +/- 21.1, and 7.5 +/- 4.1 micrograms/g lung, respectively) (p < 0.05). Serum FUDR levels were 10.5 +/- 6.8, 1.3 +/- 0.5, 2.31 +/- 1.1, and 1.2 +/- 0.4 microgram/g lung (p = not significant) for intravenous, ILP 7, ILP 14, and ILP 21 groups, respectively.

CONCLUSIONS

Isolated left lung perfusion with FUDR is well tolerated to a maximum dose of 21 mg/mL and results in significantly higher FUDR and 5-fluorouracil lung levels with low serum levels compared with intravenous treatment. These higher pulmonary levels may offer advantages in the treatment of pulmonary colorectal metastases.

Interferon gamma protects against hepatic tumor growth in rats by increasing Kupffer cell tumoricidal activity

An increasing number of hepatic resections are being performed as potentially curative surgery for malignant liver neoplasms. Hepatectomy and subsequent liver regeneration produce a local environment that enhances growth of microscopic residual tumor. To determine if pretreatment with murine interferon gamma (IFN-gamma) can protect against such enhanced tumor growth, Buffalo rats were randomized to receive a 3-day treatment of IFN-gamma (50,000 U/qD intraperitoneally) or saline. Groups then underwent intrasplenic injection of 10(6) Morris hepatoma cells, followed 1 hour later by sham (control) or partial hepatectomy (PH) of 70%. PH significantly enhanced tumor growth within the liver (control, 8 +/- 3 nodules per liver; PH, 73 +/- 12 nodules per liver; P < .001). This enhancement was attenuated by prior administration of IFN-gamma IFN-gamma/PH, 16 +/- 3; P < .001 vs. PH). Growth factor release and liver regeneration were not affected significantly by pretreatment with IFN-gamma. The effect of IFN-gamma on tumor growth is associated with a significant enhancement of Kupffer cell (KC)-mediated tumoricidal activity (percentage of specific lysis, 55 +/- 10% control, 78 +/- 11% IFN-gamma, P < .01) but not lymphocyte-mediated tumoricidal activity. Because microscopic residual disease may be present after hepatectomies for cancer, IFN-gamma may be useful agent in retarding growth of residual tumors.

Ethnic differences in analgesic consumption for postoperative pain

OBJECTIVE

To examine the influence of patient ethnicity on receipt of postoperative analgesia.

METHOD

Chart review of 250 consecutive patients hospitalized for open reduction and internal fixation of a limb fracture. Analgesics consumption in the postoperative period was measured in terms of morphine equivalents.

RESULTS

There were significant differences (p < .005) in analgesics administered to black, Hispanic, and white patients. Whites received 22 mg/day, blacks 16 mg/day, and Hispanics 13 mg/day. These ethnic differences persisted after controlling for possible confounding variables.

CONCLUSION

Ethnicity exerts a powerful impact on medical care. We cannot determine from our data whether these differences stem from differences in pain behavior of the patients or differences in medical staff's perception and treatment of such patients.

Effect of human growth hormone on human pancreatic carcinoma growth, protein, and cell cycle kinetics

The role of human growth hormone (hGH) as a nutritional adjunct for cancer patients is controversial because of its potential mitogenic effects on tumor growth. No studies to date have examined the effect of hGH on human tumor response in vivo. In Vitro: Athymic mice were injected (s.c.) daily with hGH (GH, n=14) or saline (CTL, n=14). On Day 10, serum was collected and added to human pancreatic carcinoma cells in culture. In Vivo: Athymic mice were inoculated (s.c.) with human pancreatic carcinoma cells. On Day 14, mice were randomized to receive daily either hGH (GH, n=14) or saline (CTL, n=12). On Day 29, animals received [3H]phenylalanine for tissue protein fractional synthetic rate (FSR) measurement. Tumors were excised and cell cycle kinetics analyzed. Data are expressed as mean +/- SEM. Statistical analysis was performed by unpaired t test and/or ANOVA where appropriate. In Vitro: Serum from GH-treated animals had elevated IGF-1 levels (287 +/- 34 ng/ml vs 157 +/- 53 ng/ml, P<0.001) and significantly stimulated cell growth (No. cells x 10(3)/well) compared with CTL serum (925 +/- 31 vs 747 +/- 38, P<0.001). In Vivo: Serum for GH-treated animals had elevated IGF-1 levels (287 +/- 34 ng/ml vs 157 +/- 53 ng/ml, P<0.001) and significantly stimulated cell growth (No. cells x 10(3)/well) compared with CTL serum (925 +/- 31 vs 747 +/- 38, P<0.001). In Vivo: Growth hormone had no significant effect on tumor growth rate (mm3/day) (1.45 +/- 0.47 CTL vs 1.57 +/- 0.66 GH), final tumor weight (mg) (0.19 +/- 0.15 CTL vs 0.17+/- 0.06 GH), DNA Index (1.5 +/- 0.1 CTL vs 1.5 +/- 0.1 GH), percent S phase (20.3 +/- 3.3 CTL vs 22.1 +/- 3.0 GH), or tumor FSR (%/day) (51.1 +/- 17.8 CTL vs 70.2 +/- 61.1 GH). Growth hormone significantly elevated serum IGF-1 levels (ng/ml) (176 +/- 48 CTL vs 222 +/- 53 GH, P<0.005) and liver FSR (%/day) (62.8 +/- 17.8 CTL vs 79.7 +/- 12.7 GH, P<0.005). Serum of GH-treated mice increased human pancreatic cell growth in vitro. In vivo, GH administration raised serum IGF-1 levels and increased liver protein FSR, without tumor growth, cell cycle kinetics, or protein FSR.

Isolated lung perfusion with doxorubicin reduces cardiac and host toxicities associated with systemic administration

BACKGROUND

For patients with malignant neoplasms metastatic to lung, systemic chemotherapy in doses high enough to achieve significant survival improvement is often limited by host toxicity. Isolated single-lung perfusion offers the advantage of delivering high-dose organ-specific chemotherapy while minimizing systemic toxicity. We compared the cardiac and systemic toxicities associated with intravenous administration versus isolated single-lung perfusion with doxorubicin.

METHODS

Thirty-three male Fischer 344 rats weighing 275 to 300 g were randomized into three groups: normal control rats (n = 11), intravenous doxorubicin (7/mg/kg) (n = 11), and isolated left lung perfusion with 320 micrograms doxorubicin/mL (n = 11). Animals undergoing isolated single-lung perfusion were anesthetized with pentobarbital, intubated, and ventilated, and then had left thoracotomy with cannulation of the pulmonary artery and a pulmonary venotomy; pulmonary artery and vein were clamped proximally. Animals were perfused for 10 minutes at a rate of 0.5 mL/min, followed by a 5 minute rinse with buffered hespan solution. Arteriotomy and venotomy were repaired and circulation was restored. Daily weights were recorded. On day 24, cardiac output was determined in all groups by injection of radiolabeled chromium 51 microspheres.

RESULTS

Animals treated with 7 mg/kg intravenous doxorubicin had a significant weight loss as compared with those treated with isolated lung perfusion (209.2 +/- 29.9 g versus 302.3 +/- 10.1 g; p < 0.01). Animals treated with isolated single-lung perfusion, after recovering from surgical stress, resumed normal growth pattern. Significant cardiac toxicities were seen in intravenously treated animals; cardiac index (27.4 +/- 6.9 versus 39.4 +/1 6.3 mL/min/100g body weight and heart weights (0.56 +/- 0.04 versus 0.88 +/- 0.09 g) were reduced in the intravenously treated group as compared with the group treated with isolated single-lung perfusion. In addition, severe hematologic toxicities are associated with intravenous doxorubicin administration.

CONCLUSIONS

Intravenous administration of doxorubicin is associated with severe host toxicities, which include weight loss, decreased cardiac function, and hematologic toxicity. Isolated lung perfusion with high-dose doxorubicin is well tolerated and is associated with minimal host toxicity.

The role of general practitioners in mental health care: a survey of needs and problems

OBJECTIVE

To assess the attitudes of general practitioners to central Auckland mental health service provision, and their perceived role and educational needs for clinical management of patients with mental disorders.

METHOD

A postal questionnaire survey of all general practitioners within the Auckland Healthcare (Central Auckland CHE) area.

RESULTS

140 (49%) valid responses were returned from 287 sampled. 94% supported a shared care role with mental health services; 57% considered their role as main case manager to be important. 79% of the general practitioners considered they had insufficient time to manage patients with mental disorders. 69% of respondents reported difficulties receiving information about changes to treatment; 65% were unsure whether patients had a case manager, and 64% reported general difficulties with liaison with the mental health services. Education about a range of mental health issues was sought by three quarters of the group.

CONCLUSION

This survey suggested that liaison between general practice and specialist mental health services in central Auckland is poor, but that general practitioners are eager to seek ways to improve the care of people suffering mental disorders.

Pulmonary artery perfusion of doxorubicin with blood flow occlusion: pharmacokinetics and treatment in a metastatic sarcoma model

BACKGROUND

We compared pharmacokinetics, toxicity, and treatment efficacy of pulmonary artery perfusion of low-dose doxorubicin with blood flow occlusion to intravenous doxorubicin injection in a metastatic sarcoma model in the rat.

METHODS

Animals received left pulmonary artery perfusion with 0.1, 0.2, or 0.5 mg/kg doxorubicin at a rate of 0.1 mL/min for 1 minute with 20 minutes of blood flow occlusion. Doxorubicin levels of the lung, heart, and serum were assayed. Body weights after treatment were recorded and right pneumonectomy was performed. The results were compared with those in rats that received 5 mg/kg doxorubicin by intravenous injection or the saline group. Pulmonary sarcoma metastases were treated with 0.5 mg/kg doxorubicin through lung perfusion or intravenously, or with saline solution.

RESULTS

Doxorubicin levels in the lung, heart, and serum were 112.1 +/- 9.2 micrograms/g, 1.7 +/- 0.2 microgram/g, and 0.3 +/- 0.1 microgram/mL in the group with 0.5 mg/kg doxorubicin perfusion, versus 24.8 +/- 1.9 microgram/g, 10.1 +/- 1.3 microgram/g, and 0.7 +/- 0.2 microgram/mL in the intravenous group (p < 0.05). Animals had normal growth patterns and survived after right pneumonectomy in the perfused group, whereas the intravenous group failed to thrive. No tumors were found or a significant reduction in nodules was noted in the lungs treated with perfusion as compared with untreated right lungs or the intravenous and saline groups.

CONCLUSION

This chemotherapy model has important pharmacokinetic advantages and causes an increased treatment response for pulmonary metastatic sarcoma with minimal systemic and local toxicity as compared with systemic doxorubicin administration.

Isolated single-lung perfusion: a study of the optimal perfusate and other pharmacokinetic factors

BACKGROUND

Isolated single-lung perfusion with doxorubicin hydrochloride was shown to be effective in clearing experimental sarcoma lung metastases in the rat. The best perfusate to be used for isolated lung perfusion and factors affecting the final lung concentration of doxorubicin are the subject of the present study.

METHODS

In experiment 1, 60 animals were randomized to undergo isolated left lung perfusion with doxorubicin with six different perfusates (n = 10 per group): saline, low-potassium-dextran, 5% albumin, 6% hetastarch, 5% buffered albumin, and 6% buffered hetastarch. Five animals served as negative controls. After perfusion, the lung wet to dry ratio and final lung doxorubicin concentration were determined. In experiment 2, 60 animals underwent isolated left lung perfusion with either 80 micrograms/mL or 320 micrograms/mL of doxorubicin. Animals were perfused at either 0.5 mL/min or 1 mL/min and for 2, 6, or 10 minutes. At the end of the perfusion period, the left lung doxorubicin concentration was measured. Statistical analysis included analysis of variance, the Duncan test for multiple comparisons, and multiple linear regression analysis. Significance was defined as a p value of less than 0.05.

RESULTS

In experiment 1, perfusion with 6% buffered hetastarch resulted in the lowest lung wet to dry ratio, significantly different from all groups except the controls. Perfusion with low-potassium-dextran solution led to the highest final lung concentration of doxorubicin. In experiment 2, a model to predict final lung doxorubicin concentration was constructed: Log (final lung concentration) = 1.9 + 0.0071.P + 0.186.T, where P is the measured perfusate concentration of doxorubicin, and T is the time of perfusion in minutes. The R2 was 0.91 and p, less than 0.001. The dose of doxorubicin per kilogram of animal body weight, the dose of doxorubicin per square meter of body surface area, the total amount of doxorubicin delivered, and the rate of perfusion did not meet the criteria to enter the equation.

CONCLUSIONS

Isolated lung perfusion experiments should use 6% buffered hetastarch as the perfusate. The perfusate doxorubicin concentration and the duration of perfusion are the only factors determining the final lung concentration of doxorubicin. In lung perfusion experiments, the dose of chemotherapy is not as important as the perfusate concentration and the duration of the perfusion. Animals should be perfused at a lower rate so the lungs are exposed to less doxorubicin without changing the final lung concentration.

Hypoglycemia with glycerol salvage: a role in anti-neoplastic therapy?

Most tumors are obligate glucose consumers and severe glucose depletion has anti-neoplastic effects. However, an alternate energy source is necessary to support the host. Since glycerol is utilized by all hypoglycemic sensitive normal tissues but not tumors, glycerol may be an ideal alternate energy source. The effects of glycerol on tumor growth, animal survival during systemic hypoglycemia induced by 3-mercaptopicolinic acid (3-MP, a gluconeogenesis inhibitor), and effects of 3-MP on gluconeogenesis from glycerol were studied. Experiment 1-glycerol effect on tumor cell growth; and glycerokinase activity assay. Methylcholanthrene-induced (MCA) sarcoma cells were plated in either glucose free, glucose or glycerol containing medium. Cell counts and viabilities were recorded daily. Cells in glucose group had normal growth pattern and cell viability, while cell counts and viabilities in control and glycerol groups decreased markedly. F344 rats were injected with MCA-sarcoma cells in the flank. Glycerokinase activities in tumor and host liver were assayed on day 20. Activities were 12.3 +/- 2.8, 148.2 + 17.5 assayed on day 20. Activities were 12.3 +/- 2.8, 148.2 +/- 17.5 mumol/g protein/min in tumor and liver, respectively. Experiment 2-glycerol effect on animal survival during hypoglycemia induced by 3-MP. Following a 48 hour fast, 12 Fischer 344 rats were injected (ip) with 3-MP (200mg/kg) and randomized to saline or glycerol perfusion (100mg/kg/hr) groups. Four of 6 rats in the saline group died of hypoglycemia. All rats in the glycerol group survived, but blood glucose levels were increased as compared to the saline group. Experiment 3-3-MP effect on gluconeogenesis from glycerol as compared to lactate. 5 x 10(6) hepatocytes were incubated in glucose-free HBSS containing glycerol (20mM) or lactate (20mM) in the presence (0.5mM) or absence of 3-MP. Glucose production was assayed every 30 minutes for 2 hrs. Glucose production from glycerol was not significantly inhibited in the presence of 3-MP as compared to lactate.

CONCLUSION

Glycerol does not support MCA-sarcoma growth and promotes animal survival during severe systemic hypoglycemia induced by 3-MP. However, glycerol also led to increased gluconeogenesis in this model. The use of hypoglycemic agents with glycerol protection of host tissues warrants further study.

The measurement of ionic conductivities and mobilities of certain less common organic ions needed for junction potential corrections in electrophysiology

Junction potential corrections are often required in electrophysiological measurements, particularly when using the patch-clamp technique. The ionic conductivities and mobilities of certain less common organic ions were measured for use in junction potential corrections in electrophysiological measurements. The mobilities of these ions relative to K+ were: aspartate (0.30), choline (0.51), gluconate (0.33), glutamate (0.26), HEPES (0.30), isethionate (0.52), MES (0.37), MOPS (0.35), N-methyl-D-glucamine (0.33), and Tris (0.40). In addition, junction potentials were directly measured for a number of typical simplified patch-clamp solutions containing these ions. The measured junction potentials generally agreed well with the values calculated using the Generalized Henderson Equation with the appropriate ionic mobility. The accuracy of the measurements is discussed.

Isolated lung perfusion with FUDR is an effective treatment for colorectal adenocarcinoma lung metastases in rats

Currently, the only treatment capable of significantly prolonging survival in patients with isolated pulmonary metastases from colorectal adenocarcinoma is complete resection. Systemic chemotherapy has been shown to provide little benefit. We evaluated the efficacy of highdose, organ-specific 2'-deoxy-5-fluorouridine (FUDR) using a model of isolated single-lung perfusion (ILP) in the rat. On day 0, 28 BDIX rats were inoculated intravenously with 10(6) viable Sp-5 colorectal adenocarcinoma cells. On day 10 after-tumor inoculation, animals were randomized into five treatment groups. Group I received a continuous intravenous infusion of FUDR (1 mg.kg-1.d-1) for 7 days administered by an osmotic minipump. Group II underwent isolated left lung perfusion with a buffered Hespan solution, groups III to V underwent ILP with 3.5, 7, and 14 mg of FUDR per milliliter of the buffered Hespan solution, respectively. Animals undergoing ILP were anesthetized with pentobarbital, intubated, and ventilated, and then underwent left thoracotomy with cannulation of the pulmonary artery; the pulmonary artery and vein were clamped proximally. Groups II to V were perfused for 20 minutes at a rate of 1 mL/min, followed by a 5-minute washout with FUDR-free buffered Hespan solution. On day 26 after tumor inoculation, the animals in all groups were sacrificed and their lungs were stained and counted. Animals that underwent ILP with 14 mg of FUDR per milliliter of the buffered Hespan solution showed a significant decrease in the number of tumor nodules on the treated side versus the number on the untreated side (455.2 +/- 87.3 versus 11 +/- 6.4; p < 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

Unilateral pulmonary artery occlusion inhibits growth of metastatic sarcoma in the rat lung

Tumors depend on their blood supply for growth. The blood supply to metastatic neoplasia of lung is usually from the pulmonary circulation or both the pulmonary and systemic circulation. The antineoplastic effect of pulmonary artery occlusion was investigated in a rat model of methylcholanthrene-induced metastatic pulmonary sarcoma. Left pulmonary artery ligation was performed on day 7 after tumor inoculation, and animals were sacrificed on day 14. The tumor burden of the left lung decreased 44% when compared with the control group. The survival of non-tumor-bearing rats undergoing left pulmonary artery ligation for 24 hours followed by right pneumonectomy after 2 weeks was also studied. No significant lung damage after a period of left pulmonary artery ligation was seen, as evidenced by both survival after contralateral right pneumonectomy and histology. Balloon occlusion of pulmonary artery, together with regional chemotherapy for patients with lung metastases, may warrant investigation.

Isolated single-lung perfusion with TNF-alpha in a rat sarcoma lung metastases model

We conducted a trial of isolated lung perfusion using tumor necrosis factor (TNF) in an experimental sarcoma lung metastasis model. In an in vitro experiment, methylcholanthrene-induced sarcoma cells were incubated for 48 hours with 42 micrograms/mL of either human or murine TNF. Controls were incubated with Hank's balanced salt solution. In an in vivo experiment, 23 F344 rats were injected with 10(7) methylcholanthrene-induced sarcoma cells. On day 7, 4 animals were perfused with 210 micrograms of murine TNF, 5 animals were perfused with 420 micrograms of murine TNF, 10 animals underwent isolated lung perfusion with 420 micrograms of human TNF, and 4 animals were injected systemically with 420 micrograms of human TNF. Animals were sacrificed on day 14 and the lung nodules counted. The cells incubated with murine TNF exhibited a 21% decrease in growth (p = 0.07); cells incubated with human TNF showed a 37% decrease in growth (p < 0.05). Animals perfused with 210 micrograms/mL of murine TNF and animals treated by systemically administered human TNF showed no tumor response. Animals perfused with 420 micrograms/mL of murine TNF had 7.8 +/- 14.2 nodules on the left lung and 58.5 +/- 66.0 nodules on the right lung (p = 0.07). Animals perfused with 420 micrograms/mL of human TNF had 21.7 +/- 18.3 nodules on the left lung and 91.7 +/- 66.2 nodules on the right lung (p < 0.01). On the basis of these findings, we conclude that isolated lung perfusion with TNF can be done safely in the rat and is effective in decreasing the growth of sarcoma lung metastases.

Effect of growth hormone on tumor and host in an animal model

BACKGROUND

The relative effects of growth hormone on tumor versus host growth and protein metabolism are not known. This study examines the influence of recombinant rat growth hormone (r-rGH) on host and tumor growth, host body composition, and protein synthesis of tumor and host in tumor-bearing rats.

METHODS

After left flank implantation of methylcholanthrene-induced sarcoma, 28 Fischer rats with palpable tumor were treated with s.c. saline or 1 mg/kg/day r-rGH for 11 days. At death, fractional protein synthetic rates (FSRs) of tumor, liver, and gastrocnemius muscle were determined. In a separate experiment, 27 tumor-bearing rats received saline or 1 mg/kg/day r-rGH for 2 weeks. Tumor and host growth and host body composition were analyzed.

RESULTS

Animals treated with r-rGH had significantly higher liver FSR than did controls (233 +/- 27%/day vs. 110 +/- 4%/day, respectively). No significant differences were associated with growth hormone administration with respect to tumor growth, host composition, or FSR of tumor or muscle.

CONCLUSIONS

Growth hormone stimulates liver protein synthesis, without changing tumor growth, protein synthesis, or host composition in this rat sarcoma model. Further investigation of growth hormone as an anticachectic agent is warranted.

A simplified method for endotracheal intubation in the rat

Endotracheal intubation in small laboratory animals is often necessary for survival experiments. Methods of airway control have included tracheostomy, blind intubation, and intubation under direct vision. Most of these methods are unsatisfactory and associated with high failure and complication rate. We developed an easy method of endotracheal intubation in the rat that requires simple material that is easily available to any research facility. The animals were anesthetized with pentobarbital sodium, the tongue was pulled out, and an otoscope was introduced into the oropharynx. By direct vision, a guide wire was inserted into the trachea and a 16-gauge intravenous catheter was glided over the wire. The first group of 70 rats underwent left thoracotomy with endotracheal intubation and mechanical ventilation at our laboratory as part of a study on isolated lung perfusion. The second group of five rats was anesthetized with pentobarbital, and a left carotid catheter and an endotracheal tube were inserted. Animals were ventilated with 100% O2. Arterial blood gases were sampled before intubation, 30 min after ventilation, and 60 min after extubation. In the first group, 94.3% (66 of 70) of the animals survived surgery and mortality was not directly related to the intubation and/or ventilation. All five animals of the second group survived the procedure to be extubated. Arterial PO2 before intubation, 30 min after intubation and ventilation, and 60 min after extubation was 77.1 +/- 8.5, 465.0 +/- 55.6, and 98.9 +/- 12.8 Torr, respectively. PCO2 at the same time points was 42.5 +/- 10.1, 35.1 +/- 6.3, and 32.7 +/- 6.5 Torr, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Isolated single lung perfusion with doxorubicin is effective in eradicating soft tissue sarcoma lung metastases in a rat model

The only effective therapy for patients with metastatic soft tissue sarcoma in the lung is surgical resection, with a 5-year survival of approximately 25%. Because systemic chemotherapy has not significantly affected survival in these patients, we began to investigate locoregional chemotherapy. We have previously shown that isolated single lung perfusion with doxorubicin in the rat results in higher lung tissue levels and lower systemic toxicity than does high-dose intravenous therapy. In the present study, we examined the safety of isolated lung perfusion with doxorubicin and its efficacy in the treatment of experimental pulmonary metastases from soft tissue sarcoma. In experiment 1, 15 F344 rats were randomized into three groups (n = 5): group I had isolated left lung perfusion with doxorubicin 320 micrograms/ml in saline solution; group II had left isolated lung perfusion with doxorubicin 480 micrograms/ml and group III with doxorubicin 640 micrograms/ml. All perfusions with doxorubicin were at 0.5 ml/min for 10 minutes followed by perfusion of saline solution for 5 minutes. On day 21, all animals underwent right (contralateral) pneumonectomy and were observed for over 10 days. In experiment 2, two groups of F344 rats were injected intravenously with 10(7) viable methylcholanthrene-induced sarcoma cells on day 0. On day 7, group I (n = 12) had left isolated lung perfusion with saline solution only and group II (n = 15) had isolated lung perfusion with doxorubicin 320 micrograms/ml. On day 21, all animals were killed, and their lungs were stained for metastases. Routine histologic sections from three animals from group II were examined. In experiment 1, 80% of the animals in group I survived contralateral pneumonectomy. There were no survivors in groups II and III. In experiment 2, three animals died after isolated lung perfusion (one from group I and two from group II), and one animal (group I) was excluded because of mediastinal tumor. All animals in both groups had massive tumor replacement of the right (untreated) lung. Group I animals had massive tumor replacement of the left (treated) lung, whereas animals in group II had eradication of metastases in nine of ten cases; no microscopic evidence of tumor was detected in all three animals evaluated for microscopic disease. Isolated lung perfusion with doxorubicin 320 micrograms/ml is safe and effective in eradicating experimental pulmonary sarcoma metastases in this model.

Growth hormone administration preserves lean body mass in sarcoma-bearing rats treated with doxorubicin

Cachexia and malnutrition play a significant role in the morbidity associated with antineoplastic chemotherapy regimens. Conventional nutritional support during cancer therapy has shown little benefit in terms of reducing morbidity and mortality. We examined the anabolic properties of growth hormone (GH) that preserve normal body composition in sarcoma-bearing animals treated with doxorubicin. On day 0, 40 male Fischer 344 rats were inoculated with 10(6) methylcholanthrene-induced sarcoma cells s.c. in the left flank. On day 9, animals were randomized into 3 groups: control (CTL, n = 13); doxorubicin (DOX, n = 13); and doxorubicin plus GH (DOX-GH, n = 14). Two CTL animals were excluded due to tumor invasion into the peritoneal cavity. From day 9 to day 23, the DOX-GH group received daily s.c. recombinant rat GH injection (1 mg/kg). On day 13, DOX and DOX-GH groups received 7 mg/kg of DOX i.v. while the CTL group received sham i.v. sterile saline injection. Body weight and tumor dimensions were measured daily. On day 23, all animals were weighed and sacrificed. Tumors were resected and weighed. Body composition analysis was performed. Plasma GH levels were measured by radioimmunoassay and insulin growth factor 1 levels were measured by chondrocyte proliferation bioassay. The DOX-GH group had a significantly higher mean body weight, carcass weight, total fat free body mass, insulin growth factor 1, and GH plasma levels as compared to the DOX group. No difference in total food intake was observed between the DOX and DOX-GH groups. There was no difference in final tumor weight and tumor growth rate between DOX and DOX-GH groups. Exogenous growth hormone can attenuate weight loss and preserve host body composition in tumor-bearing rats treated with doxorubicin without stimulating tumor growth.

Isolated single-lung perfusion with doxorubicin is pharmacokinetically superior to intravenous injection

To investigate new modalities in the treatment of pulmonary metastases we developed a model of isolated single-lung perfusion in the rat. In this study we compare the pharmacokinetics of isolated lung perfusion and intravenous doxorubicin. In the first experiment, designed to evaluate lung tissue levels of doxorubicin, 35 rats were randomized into seven groups (n = 5). The first five groups underwent isolated lung perfusion with 72.1 +/- 6.9, 118.4 +/- 12.1, 255.2 +/- 12.8, 384.1 +/- 46.2, and 457.6 +/- 32.5 micrograms/mL of doxorubicin, respectively, for 10 minutes. Groups 6 and 7 received 5 mg/kg and 7 mg/kg of intravenous doxorubicin, respectively. A second study was designed to measure heart tissue level of doxorubicin in 3 groups of 5 rats each. Two groups received 5 or 7 mg/kg of intravenous doxorubicin and a third group underwent isolated lung perfusion with 255.2 +/- 12.8 micrograms/mL of doxorubicin for 10 minutes. A third study, designed to evaluate toxicity in vivo, had a similar design, and the animals were followed up for 21 days after treatment. Lung doxorubicin concentration after isolated lung perfusion was significantly higher than after intravenous doxorubicin (p < 0.01). Tissue doxorubicin concentration was 25 and 20 times higher after isolated lung perfusion with 255.2 +/- 12.8 micrograms/mL than after 5 or 7 mg/kg of intravenous doxorubicin, respectively. Heart concentration of doxorubicin was significantly lower after isolated lung perfusion with 255.2 +/- 12.8 micrograms/mL of doxorubicin as compared with 5 or 7 mg/kg of intravenous doxorubicin (p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Isolated single lung perfusion in the rat: an experimental model

To evaluate isolated single lung perfusion with chemotherapy in a rat lung metastasis model, we developed a model of in vivo isolated single lung perfusion. Twenty male rats were anesthetized with pentobarbital sodium (50 mg/kg) and intubated endotracheally. A left thoracotomy was performed with an operating microscope (x16 magnification), the left pulmonary artery was cannulated, and a left pulmonary venotomy was performed. Isolated left lung perfusion was performed for 10 min at 0.5 ml/min with heparinized whole blood (n = 10) or 0.9% normal saline (n = 10). Pulmonary vein effluent was collected by suction. Nineteen of the 20 (95%) animals survived isolated left single lung perfusion. Twenty-one days after isolated left lung perfusion right pneumonectomy was performed. Fifteen of the 19 animals (78%) survived right pneumonectomy. Postoperatively, animals that survived surgery recovered preoperative body weight. In vivo isolated single lung perfusion in rats is feasible with low mortality and morbidity and may be useful in the study of isolated perfusion with chemotherapy and in diverse physiological and pharmacological experiments.

Dextropropoxyphene addiction--a drug of primary abuse

In order to establish a profile of the abuser of dextropropoxyphene (DPX) in our community, we reviewed all the records from the Detoxification Unit in the Mental Health Institute in Mexicali, Baja California, Mexico. A total of 209 records were reviewed, and 73 were included in our study. Those included had a diagnosis of DPX dependence according to DSM-III-R and no associated psychiatric pathology. Most of them were single, unemployed males, with a history of at least 4 years of continuous DPX abuse. They were consuming an average dose per day 3.5 times higher than the maximum therapeutic dose recommended. The onset of generalized seizures associated with the DPX abuse was confirmed in 53% of the cases. The drug most frequently abused along with DPX was a benzodiazepine (p < .01), followed by marijuana, heroin, alcohol, stimulants (cocaine and amphetamines), and inhalants; 17% of the cases were pure DPX abusers. DPX was the first opiate ever abused in 67% of the cases, 19% had abused heroin before DPX, and 14% started the use of both at the same time. The difference among these groups (p < .01) suggests DPX as an opiate of primary abuse and not as secondary to heroin dependence.

Vascular permeability during the early and late phases of ocular anaphylaxis

The role of enhanced vascular permeability in a model of ocular anaphylaxis was investigated during both early- and late-phase reactions (EPR and LPR). Vascular permeability was assessed by measuring the extravascular retention of 125I-bovine serum albumin (125I-BSA) in ocular tissues. Ten groups of guinea pigs (n = 5-12 per group) were injected with dinitrophenylated (DNP) bovine gamma globulin emulsified in Freund's adjuvants and challenged after a 4-week interval by topical application of di-DNP-lysine to one eye and phosphate-buffered saline to the other eye. Thereafter, the eyes were examined and the animals were killed at different intervals after topical challenge. They were injected intravenously with 125I-BSA 0.5 hr before death. Retained radioactivity was measured separately in four tissues. The EPR (period between 0.5-1.5 hr after challenge) was characterized by enhanced retention of radioactivity in lids, conjunctiva, and orbital content. There was no significant retention of extravascular radioactivity in the globe and lacrimal gland. Thereafter (period between 2-3.5 hr after challenge), retained radioactivity was significantly diminished. The subsequent period, between 4.5-6.5 hr (LPR), was characterized by a smaller, although significant, increment of radioactivity retained in lids and conjunctiva but not in the other tissues examined. These findings indicate that enhanced microvascular permeability occurs during two phases in actively immunized guinea pigs challenged topically with di-DNP-lysine and that these phases correspond to the clinical signs that constitute the EPR and LPR of ocular anaphylaxis.

Extracellular siderophores of rapidly growing Aspergillus nidulans and Penicillium chrysogenum

The highly active extracellular siderophores previously detected in young cultures of Aspergillus nidulans and Penicillium chrysogenum have been identified as the cyclic ester fusigen (fusarinine C), and its open-chain form, fusigen B (fusarinine B).