Trimetrexate for the treatment of Pneumocystis carinii pneumonia in patients with the acquired immunodeficiency syndrome

Preclinical studies have demonstrated that trimetrexate is a potent inhibitor of dihydrofolate reductase from Pneumocystis carinii. On the basis of this evidence, this lipid-soluble antifolate was used as an antipneumocystis agent in 49 patients with the acquired immunodeficiency syndrome (AIDS) and pneumocystis pneumonia. Simultaneous treatment with the reduced folate leucovorin was used as a specific antidote to protect host tissues from the toxic effects of the antifolate without affecting the antipneumocystis action of trimetrexate. Patients were assigned to three groups and treated for 21 days: in Group I, trimetrexate with leucovorin was used as salvage therapy in patients in whom standard treatments (both pentamidine isethionate and trimethoprim-sulfamethoxazole) could not be tolerated or had failed (16 patients); in Group II, trimetrexate with leucovorin was used as initial therapy in patients with a history of sulfonamide inefficacy or intolerance (16 patients); and in Group III, trimetrexate with leucovorin plus sulfadiazine was used as initial therapy (17 patients). The response and survival rates were, respectively, 69 percent and 69 percent in Group I; 63 percent and 88 percent in Group II; and 71 percent and 77 percent in Group III. Trimetrexate therapy had minimal toxicity; transient neutropenia or thrombocytopenia occurred in 12 patients and mild elevation of serum aminotransferases in 4. We conclude that the combination of trimetrexate and leucovorin is safe and effective for the initial treatment of pneumocystis pneumonia in patients with AIDS and for the treatment of patients with intolerance or lack of response to standard therapies.     

Nitric Oxide-Associated Pulmonary Edema in Children With Pulmonary Venous Hypertension

Nitric oxide (NO)-associated pulmonary edema is rarely reported in children; in adults, it is often associated with left-sided heart failure. We report a case series of children with NO-associated pulmonary edema, which was defined as new multilobar alveolar infiltrates and worsening hypoxemia within 24 h of initiation or escalation of NO and radiologic or clinical improvement after NO discontinuation. We identified six patients (0.4–4 years old) with ten episodes of NO-associated pulmonary edema. Diagnoses included atrioventricular canal defect with mitral valve disease (n = 2), pulmonary atresia and major aorta-pulmonary collateral arteries (n = 2), total anomalous pulmonary venous return (n = 1), and pulmonary veno-occlusive disease (n = 1). All patients had evidence of pulmonary venous hypertension, and two had mitral valve disease resulting in clinical evidence of left-sided heart failure. Pulmonary edema improved or resolved within 24 h of discontinuing NO. At cardiac catheterization, mean left atrial pressure was <15 mmHg in three of three patients (none with mitral valve disease), whereas pulmonary artery occlusion pressure was >15 mmHg in two of five patients. In conclusion, we describe six young children with NO-associated pulmonary edema and pulmonary venous hypertension. Only two of these children had left-sided heart failure: Left atrial pressure as well as pulmonary artery occlusion pressure may not be helpful in identifying children at risk for NO-associated pulmonary edema.     

Mutation spectrum and genotype-phenotype analyses in Cowden disease and Bannayan-Zonana syndrome, two hamartoma syndromes with germline PTEN mutation

The tumour suppressor gene PTEN , which maps to 10q23.3 and encodes a 403 amino acid dual specificity phosphatase (protein tyrosine phosphatase; PTPase), was shown recently to play a broad role in human malignancy. Somatic PTEN deletions and mutations were observed in sporadic breast, brain, prostate and kidney cancer cell lines and in several primary tumours such as endometrial carcinomas, malignant melanoma and thyroid tumours. In addition, PTEN was identified as the susceptibility gene for two hamartoma syndromes: Cowden disease (CD; MIM 158350) and Bannayan-Zonana (BZS) or Ruvalcaba-Riley-Smith syndrome (MIM 153480). Constitutive DNA from 37 CD families and seven BZS families was screened for germline PTEN mutations. PTEN mutations were identified in 30 of 37 (81%) CD families, including missense and nonsense point mutations, deletions, insertions, a deletion/insertion and splice site mutations. These mutations were scattered over the entire length of PTEN , with the exception of the first, fourth and last exons. A 'hot spot' for PTEN mutation in CD was identified in exon 5 that contains the PTPase core motif, with 13 of 30 (43%) CD mutations identified in this exon. Seven of 30 (23%) were within the core motif, the majority (five of seven) of which were missense mutations, possibly pointing to the functional significance of this region. Germline PTEN mutations were identified in four of seven (57%) BZS families studied. Interestingly, none of these mutations was observed in the PTPase core motif. It is also worthy of note that a single nonsense point mutation, R233X, was observed in the germline DNA from two unrelated CD families and one BZS family. Genotype-phenotype studies were not performed on this small group of BZS families. However, genotype-phenotype analysis inthe group of CD families revealed two possible associations worthy of follow-up in independent analyses. The first was an association noted in the group of CD families with breast disease. A correlation was observed between the presence/absence of a PTEN mutation and the type of breast involvement (unaffected versus benign versus malignant). Specifically and more directly, an association was also observed between the presence of a PTEN mutation and malignant breast disease. Secondly, there appeared to be an interdependent association between mutations upstream and within the PTPase core motif, the core motif containing the majority of missense mutations, and the involvement of all major organ systems (central nervous system, thyroid, breast, skin and gastrointestinal tract). However, these observations would need to be confirmed by studying a larger number of CD families.      

First-line treatment for osteoarthritis. Part 1: Pathophysiology,assessment, and pharmacologic interventions

While surgical interventions often relieve severe pain for those with osteoarthritis (OA), there are thousands of patients with this common and disabling condition who do not receive surgery. Pharmacologic and nonpharmacologic interventions may offer a reduction in pain and improvement in physical functioning. To help patients with OA, nurses should conduct thorough assessments based on pathophysiology, and plan appropriate care with the patient. In this first article of a two-part series, the pathophysiology and classification of OA are presented. Assessment factors are discussed, and pharmacologic interventions are presented. Part 2 of this series, to run in the November/December issue, will focus on nonpharmacologic interventions and evaluation.     

First-line treatment for osteoarthritis. Part 2: Nonpharmacologic interventions and evaluation

Because of the chronic nature of osteoarthritis, nonpharmacologic interventions provide the client with self-care strategies that may lessen pain, improve physical functioning, and increase independence and sense of control. Nonpharmacologic interventions include exercise, rest and joint protection, heat and cold, hydrotherapy, therapeutic touch, acupuncture/acupressure, biofeedback, hypnotherapy, cognitive-behavioral techniques, activity and home maintenance modification, nutrition, and transportation interventions. Most of these therapies are very useful for nurses as independent interventions. Suggestions for evaluation of interventions are made.     

Generating mouse models of retinal disease using ENU mutagenesis

We used the chemical mutagen, N-ethyl-N-nitrosourea, to induce random point mutations in the germline of the mouse strain C57BL/6 in order to generate models of retinal diseases. 1163 mutagenised first generation mice produced using this approach were examined for eye abnormalities. Approximately one-third (412) presented with some form of ocular abnormality. Most changes were unilateral and confined to the anterior segment of the eye. Less than 10% (44) of identified changes affected the posterior segment of the eye. 21 mice with varying ocular abnormalities, including 17 with retinal changes, were bred to produce second generation mice to confirm genetic inheritance. Genetic inheritance was confirmed in several of these lines including three with retinal changes.     

MOHS for head and neck mucosal cancer: report on 111 patients

Microscopically Oriented Histologic Surgery (MOHS) has been applied to primary epidermoid cancers of the mucosal tissues of the head and neck since 1979. In that time we have treated 170 patients and maintained excellent records, losing no patients to follow-up. One hundred three patients have been followed for 2 years. Of this group, only nine patients have developed local recurrences; three were salvaged, six were not. This presentation reviews the concept of MOHS and its application to head and neck mucosal lesions. The results are analyzed, and conclusions are drawn regarding what we have learned about the biologic behavior of head and neck tumors and the role of MOHS in treating these neoplasms.