Bronchoalveolar lavage to evaluate new pulmonary infiltrates in allogeneic hematopoietic stem cell transplant recipients: impact on antimicrobial optimization.

BACKGROUND: Pulmonary complications cause significant morbidity and mortality after allogeneic hematopoietic stem cell transplant (AHSCT). Bronchoscopy with targeted bronchoalveolar lavage (BAL) is often used in AHSCT patients with suspected lower respiratory tract infection (LRTI) to help guide management. AIM: To evaluate how positive BAL results change antimicrobial management of AHSCT recipients with suspected LRTI. METHODS: We performed a retrospective review of BAL results from January 2014 to July 2016 for 54 AHSCT recipients. A positive BAL was determined by culture, multiplex polymerase chain reaction (PCR), Aspergillus galactomannan antigen (AGA), and cytology. FINDINGS: BAL was positive for infectious etiologies in 63%, and antimicrobials were adjusted in 48/54 (89%) of patients. Antibacterial escalation was predicted by a positive BAL bacterial culture (OR 7.61, P=0.017). Antibiotic de-escalation was more likely with an elevated AGA (OR 3.86, P=0.035). Antiviral initiation was more likely with positive BAL multiplex PCR (OR 17.33, P=0.010). Antifungals were more likely to be escalated or changed with an elevated AGA (OR 4.33, P=0.020). The patients with a negative BAL were more likely to be started on steroids (OR 0.19, P= 0.043). CONCLUSIONS: BAL was helpful to determine the etiology of pulmonary complications and optimize antimicrobials. The addition of AGA and multiplex PCR to standard BAL significantly impacted de-escalating antibiotics and adjusting antifungals to provide adequate coverage. The association with an elevated AGA with antibacterial de-escalation highlights a new role for BAL in antimicrobial optimization.

Anti-thymocyte globulin for conditioning in matched unrelated donor hematopoietic cell transplantation provides comparable outcomes to matched related donor recipients.

Rabbit anti-thymocyte globulin (ATG) is used as prophylaxis against GVHD following allogeneic hematopoietic cell transplantation (HCT). At our institution, ATG is exclusively used in the conditioning of matched unrelated donor (URD) transplant recipients. A total of 50 URD HCT recipients who received ATG (ATG group) were retrospectively compared with 48 matched related donor (MRD) HCT recipients who did not receive ATG (no ATG group). There were no significant differences between the groups in rates of day 100 mortality, acute GVHD or relapse. Chronic GVHD incidence was significantly lower in the ATG group (P = 0.007). At a median follow-up of 36 months in the entire cohort, 50% patients are alive in the ATG group and 63% of the patients are alive in the no ATG group (P = 0.13). We conclude that the administration of ATG to patients undergoing URD HCT preserves the anti-leukemia benefit of the transplant, while reducing the risk of developing GVHD, resulting in OS rates that are comparable to MRD HCT recipients.

Improving stem cell mobilization strategies: future directions.

Autologous hematopoietic SCT (auto-HSCT) provides hematopoietic support after high-dose chemotherapy and is the standard of care for patients with multiple myeloma (MM) or chemosensitive relapsed high- or intermediate-grade non-Hodgkin's lymphoma (NHL). However, yields of hematopoietic stem cells vary greatly between patients, and the optimal strategy to mobilize hematopoietic stem cells into peripheral blood for collection has not been defined. Current mobilization strategies consist of cytokines alone or in combination with chemotherapeutic agents. Cytokine-only mobilization regimens are well tolerated, but their utility is limited by suboptimal PBSC yields. When a myelosuppressive chemotherapeutic agent is added to a cytokine mobilization regimen, PBSC collections improve two- to five-fold. This benefit is tempered by increased toxicity, morbidity and resource utilization. All current regimens fail to mobilize sufficient hematopoietic stem cells to proceed to transplantation in 5-30% of patients, necessitating additional mobilization attempts or precluding transplantation, which may negatively affect patient outcomes and survival. Improved strategies to mobilize stem cells would increase the availability of auto-HSCT and optimize engraftment and outcomes in patients with MM or NHL. Novel agents used in conjunction with cytokines have the potential to increase PBSC collections without introducing additional morbidity, thereby improving patient outcomes.

PEPCK mRNA localization in proximal tubule and gene regulation during metabolic acidosis.

To identify the nephron segments expressing PEPCK in control and acidotic conditions, PEPCK mRNA was localized in rat kidney using the technique of reverse transcription and polymerase chain reaction (RT-PCR) in individual microdissected S1 S2, and S3 segments of the rat proximal tubule. In controls, the number of tubules expressing PEPCK mRNA was greatest in the S3 segment, moderate in the S2 segment, and least in the S1 segment of the proximal tubule. After NH4Cl feeding, strong signals for PEPCK mRNA were detected in all three proximal tubule segments. In situ hybridization demonstrated expression of PEPCK mRNA only in the medullary rays in controls. After NH4Cl, PEPCK mRNA was expressed throughout the cortex, confirming the RT-PCR results. These data demonstrate the ability of the rat kidney cortex to modulate the expression of PEPCK mRNA during metabolic acidosis by recruitment of additional cells in the proximal nephrons. Studies with cultured LLC-PK1-F+ cells indicated that increased PEPCK gene transcription at acid pH required a cis-acting element (enhancer) in the more distal 5' flanking region of the promoter.

Five days of cefprozil versus 10 days of clarithromycin in the treatment of an acute exacerbation of chronic bronchitis.

BACKGROUND: Shorter than traditional 7- to 14-day treatment regimens have demonstrated efficacy in treatment of an acute exacerbation of chronic bronchitis (AECB). OBJECTIVE: Perform a clinical efficacy study comparing 5 days of cefprozil therapy to 10 days of clarithromycin in treating an AECB. METHODS: A multicenter, randomized, double-blind study comparing efficacy and safety of cefprozil, 500 mg twice daily, for 5 days with clarithromycin, 500 mg twice daily, for 10 days in treatment of 295 subjects with AECB. Concomitantly, among all treated subjects, 39% (115 of 295) had a history of chronic obstructive pulmonary disease/emphysema; 21% (62 of 295) had a history of asthma/reactive airway disease; and 31% (90 of 295) had environmental allergies. RESULTS: There were no statistically significant differences among clinically evaluable subjects' cure rates; 82% (109 of 133) treated with cefprozil versus 85% (105 of 123) treated with clarithromycin were cured at test-of-cure visit (95% confidence interval, -12.0 to 5.1%). Clinical cure rates at end of study were 80% and 81%, respectively (95% confidence interval, -10.8 to 7.9%). Before treatment, 99% (85 of 86) of Gram-positive organisms isolated were susceptible to cefprozil and 78% (67 of 86) were susceptible to clarithromycin. A total of 84% (96 of 114) of Gram-negative organisms were susceptible to cefprozil and 63% (72 of 114) were susceptible to clarithromycin. Of clinically evaluable Streptococcus pneumoniae-infected subjects, 100% (11 of 11) of cefprozil subjects and 93% (14 of 15) of clarithromycin subjects experienced clinical cure. The most frequently reported adverse effects were nausea, 5% (7 of 150), and diarrhea, 9% (14 of 150), for cefprozil. For clarithromycin, the adverse effects were nausea, 8% (11 of 145); diarrhea, 12% (18 of 145); taste perversion, 8% (11 of 145); and dry mouth, 5% (7 of 145). CONCLUSIONS: Five days of cefprozil is as effective as 10 days of clarithromycin for treatment of an AECB.

Neuronal nitric oxide synthase: expression in rat parietal cells.

Nitric oxide synthases (NOS) are enzymes that catalyze the generation of nitric oxide (NO) from L-arginine and require nicotinamide adenine dinucleotide phosphate (NADPH) as a cofactor. At least three isoforms of NOS have been identified: neuronal NOS (nNOS or NOS I), inducible NOS (iNOS or NOS II), and endothelial NOS (eNOS or NOS II). Recent studies implicate NO in the regulation of gastric acid secretion. The aim of the present study was to localize the cellular distribution and characterize the isoform of NOS present in oxyntic mucosa. Oxyntic mucosal segments from rat stomach were stained by the NADPH-diaphorase reaction and with isoform-specific NOS antibodies. The expression of NOS in isolated, highly enriched (>98%) rat parietal cells was examined by immunohistochemistry, Western blot analysis, and RT-PCR. In oxyntic mucosa, histochemical staining revealed NADPH-diaphorase and nNOS immunoreactivity in cells in the midportion of the glands, which were identified as parietal cells in hematoxylin and eosin-stained step sections. In isolated parietal cells, decisive evidence for nNOS expression was obtained by specific immunohistochemistry, Western blotting, and RT-PCR. Cloning and sequence analysis of the PCR product confirmed it to be nNOS (100% identity). Expression of nNOS in parietal cells suggests that endogenous NO, acting as an intracellular signaling molecule, may participate in the regulation of gastric acid secretion.

Clarithromycin in the management of community-acquired pneumonia.

OBJECTIVE: To review the epidemiology and diagnosis of community-acquired pneumonia (CAP) and examine factors that influence the choice of empiric antimicrobial therapy. BACKGROUND: CAP remains a common disease with substantial associated morbidity and mortality. Outpatient management of patients with CAP has become increasingly complex because of the availability of newer antimicrobial agents, evolving patterns of resistance, and the increasing recognition of atypical pathogens. Although Streptococcus pneumoniae remains a commonly encountered pathogen, the development and increasing prevalence of antibiotic resistance has become an area of concern, especially in outpatients. The newer macrolide antimicrobial drugs-clarithromycin and azithromycin-are effective against commonly encountered pathogens, are well tolerated, and have an established tolerability profile, although the low serum levels achieved by azithromycin hinder its use in patients with suspected bacteremia. METHODS: A MEDLINE search was performed of English-language articles published from 1990 to 2000 on the treatment of CAP. This article reviews the treatment of CAP, with emphasis on the use of clarithromycin. CONCLUSION: Although laboratory surveillance studies have reported macrolide-resistant S. pneumoniae, recent evidence defining the mechanism of this resistance, coupled with the pharmacokinetic properties of the macrolide agents, suggests that the actual rate of clinical macrolide resistance is low.

Comparative safety and efficacy of cefdinir vs amoxicillin/clavulanate for treatment of suppurative acute otitis media in children.

OBJECTIVE: Two dosage regimens of cefdinir were compared with amoxicillin/clavulanate for the treatment of suppurative acute otitis media (AOM) in children. METHODS: This was an investigator-blinded, randomized, comparative, multicenter trial, in which tympanocentesis was performed in 384 patients, ages 6 months to 12 years, who had nonrefractory AOM. Patients were randomized to receive one of three 10-day treatment regimens: cefdinir 14 mg/kg daily (QD; n = 128); cefdinir 7 mg/kg twice a day (BID; n = 128); or amoxicillin/clavulanate 40/10 mg/kg/day divided for use three times a day (TID; n = 128). RESULTS: Of the 384 enrolled patients 303 were evaluable for clinical efficacy. Clinical success rates were statistically equivalent for the 3 treatment groups at the end of therapy: 85 of 102 (83.3%) for cefdinir QD; 81 of 101 (80.2%) for cefdinir BID; 86 of 100 (86%) for amoxicillin/clavulanate. Of the 197 evaluable patients from whom a susceptible pathogen was recovered, presumptive eradication rates at end of therapy were equivalent: 55 of 65 (84.6%), 54 of 66 (81.8%) and 55 of 66 (83.3%) for cefdinir QD-, cefdinir BID- and amoxicillin/clavulanate-treated patients, respectively. However, presumptive eradication rates for Streptococcus pneumoniae were significantly lower for cefdinir BID (55.2%) than for amoxicillin/clavulanate (89.5%; P = 0.0019) and marginally lower than for cefdinir QD (80%; P = 0.054). Diarrhea was the most common treatment-associated adverse reaction in all groups but was significantly more common in amoxicillin/clavulanate-treated patients (35%) than in patients who had been treated with cefdinir QD (10%, P<0.001) or cefdinir BID (13%, P<0.001). CONCLUSIONS: A 10-day regimen of cefdinir 14 mg/kg QD or 7 mg/kg BID was as clinically effective overall as a 10-day regimen of amoxicillin/ clavulanate 40/10 mg/kg/day divided TID in the treatment of tympanocentesis-confirmed, nonrefractory AOM in children. These data suggest that cefdinir QD may be a better alternative than cefdinir BID for refractory AOM. Both dosing regimens of cefdinir were associated with significantly fewer gastrointestinal adverse reactions than was amoxicillin/clavulanate.

A randomized trial of short-course ciprofloxacin, ofloxacin, or trimethoprim/sulfamethoxazole for the treatment of acute urinary tract infection in women. Ciprofloxacin Urinary Tract Infection Group.

PURPOSE: Bladder infections are very common in otherwise healthy women, and short-course antimicrobial treatment appears effective for many episodes of cystitis. This study reports the results of short-course ciprofloxacin, ofloxacin, and trimethoprim/sulfamethoxazole therapy. PATIENTS AND METHODS: We performed a randomized, double-blind study of the efficacy and safety of a 3-day course of oral ciprofloxacin 100 mg twice daily, ofloxacin 200 mg twice daily, or trimethoprim/sulfamethoxazole 160/800 mg twice daily in women with acute, uncomplicated, symptomatic lower urinary tract infection. RESULTS: A total of 866 patients were enrolled, of whom 688 (79%) were evaluated for the efficacy of treatment (229 treated with ciprofloxacin, 228 treated with trimethoprim/sulfamethoxazole, and 231 treated with ofloxacin). The most frequent reason for exclusion was the failure to identify a pretreatment pathogen. The most commonly isolated pathogen was Escherichia coli (81%). Eradication of the pretreatment pathogen at the end of therapy occurred in 94% of ciprofloxacin, 93% of trimethoprim/sulfamethoxazole, and 97% of ofloxacin-treated patients. At follow-up evaluation at 4 to 6 weeks, recurrence rates (relapse or reinfection) were 11% in the ciprofloxacin, 16% in the trimethoprim/sulfamethoxazole, and 13% in the ofloxacin treatment group. Clinical success at the end of therapy was 93% in the ciprofloxacin, 95% in the trimethoprim/sulfamethoxazole, and 96% in the ofloxacin treatment groups. The frequency of all adverse events was 31% for ciprofloxacin, 41% for trimethoprim/sulfamethoxazole, and 39% for ofloxacin-treated patients (P = 0.03). Premature discontinuation of study drug due to an adverse event was more common in trimethoprim/sulfamethoxazole-treated patients (n = 9) compared with those given ciprofloxacin (n = 2) or ofloxacin (n = 1; P = 0.02). CONCLUSION: Ciprofloxacin, ofloxacin, and trimethoprim/sulfamethoxazole had similar efficacy when given for 3 days to treat acute, symptomatic, uncomplicated lower urinary tract infection in women.

Penetration of clarithromycin into middle ear fluid of children with acute otitis media.

OBJECTIVE: To determine the steady state plasma and middle ear fluid concentrations of clarithromycin and its metabolite, 14(R)-hydroxyclarithromycin in 32 pediatric patients with acute otitis media. METHODS: After the sixth dose of a 7.5-mg/kg every-12-h regimen of clarithromycin suspension, tympanocentesis was performed at 2, 4, 8 or 12 hours postdose. Plasma and middle ear fluid samples were assayed for concentrations of clarithromycin and its 14-hydroxy metabolite. RESULTS: Mean middle ear fluid concentrations ranged from 3.0 to 8.3 micrograms/g during the dosing interval for clarithromycin and from 1.5 to 3.8 micrograms/g for 14(R)-hydroxyclarithromycin. The mean middle ear fluid concentrations were consistently greater than corresponding mean plasma concentrations, which ranged from 0.7 to 3.4 micrograms/ml for clarithromycin and from 0.8 to 1.8 micrograms/ml for 14(R)-hydroxyclarithromycin. The ratios of middle ear fluid to plasma concentration appeared to increase during the dosing interval and were 8.8 and 3.8 for clarithromycin and 14(R)-hydroxyclarithromycin, respectively, 12 h after dosing. CONCLUSIONS: Multiple oral doses of clarithromycin suspension produced sustained middle ear fluid concentrations of clarithromycin and 14(R)-hydroxyclarithromycin which exceed the minimum inhibitory concentrations of most otic pathogens.

Intralesional fluorouracil/epinephrine injectable gel for treatment of condylomata acuminata. A phase 3 clinical study.

BACKGROUND AND DESIGN: A new intralesional sustained-release chemotherapy is under development as a treatment for condylomata acuminata; it is administered as an injectable gel that consists of fluorouracil and epinephrine with a purified bovine collagen as the gellant (fluorouracil/epinephrine gel). In this randomized, double-blind study, we evaluated the safety and efficacy of this intralesional treatment in 401 patients, using 2 active drug formulations (fluorouracil/epinephrine gel and fluorouracil gel alone) and a placebo. Each lesion was injected once a week for up to 6 weeks, and patients were followed up for 3 months. RESULTS: A total of 359 patients with 1926 condylomata underwent evaluation. For all lesions treated with fluorouracil/epinephrine gel, the complete response (CR) rate was 77%. For all patients treated with fluorouracil/epinephrine gel, the CR rate was 61%. The fluorouracil/epinephrine gel was significantly more effective (P < .002) in treating condylomata than the fluorouracil gel without epinephrine (CR rate, 43%); both were superior to placebo (CR rate, 5%). At 3 months after completion of treatment, recurrence rates in patients with CRs were as follows: fluorouracil/epinephrine gel group, 50%; fluorouracil gel group, 58%. No clinically significant drug-related systemic reactions occurred. Finally, the type and severity of local tissue reactions of patients with a positive pretreatment collagen skin test result (6/401 [1.5%]) were similar to those of patients with a negative collagen skin test result. CONCLUSION: The fluorouracil/epinephrine injectable gel is a safe and effective treatment for condylomata acuminata.

Development of intralesional therapy with fluorouracil/adrenaline injectable gel for management of condylomata acuminata: two phase II clinical studies.

OBJECTIVES: To evaluate a sustained release chemotherapy for treating condylomata acuminata with an injectable gel containing fluorouracil and adrenaline (5-FU/adrenaline gel). Study 1-- To assess contributions of the components of 5-FU/adrenaline gel to efficacy. Study 2--To assess therapeutic contribution of adrenaline and safety and efficacy of the formulations. DESIGN: Randomised, double blind, placebo controlled studies. SETTING: Private practices and university clinics in the United States. PATIENTS: Men and women with new, recurrent, or refractory external condylomata acuminata. INTERVENTION: Six injections over 8 weeks; follow up visits at weeks 1, 4, 8, and 12. EFFICACY: patient/wart response, times to complete response, recurrence rates. SAFETY: injection reactions, tissue conditions, other adverse events, laboratory studies. RESULTS: Study 1: 132 evaluable patients. Complete response (CR) rate was highest for the 5-FU/adrenaline gel group, followed by the 5-FU/adrenaline solution group, then the 5-FU gel group. 5-FU, adrenaline, and the collagen gel vehicle (in the presence of 5-FU) significantly affected CR and strongly influenced time to CR. The effects of 5-FU and adrenaline were statistically significant. Cutaneous reactions were mild to moderate. Study 2: 187 evaluable patients. Patients treated with 5-FU/adrenaline gel had a significantly higher CR rate and lower cumulative 90 day recurrence rate than those treated with 5-FU gel without adrenaline. Treatments were generally well tolerated, with only three treatment related, serious adverse events. CONCLUSION: 5-FU/adrenaline gel is safe and efficacious for treatment of condylomata acuminata, and when compared with individual or various combinations of components, this formulation provided the greatest therapeutic advantage.

Azithromycin (zithromax).

Azithromycin (Zithromax), Pfizer, Inc., New York, NY) is a 15-membered-ring macrolide and the first azalide antibiotic. It is distinguished from other macrolides by its rapid and extensive penetration into intracellular and interstitial tissue compartments, accompanied by prolonged tissue and serum half-lives. Azithromycin shares the gram-positive activity of erythromycin but is more potent against gram-negative organisms. For urethritis and cervicitis caused by Chlamydia trachomatis, azithromycin is effective and well tolerated in a single dose of 1 g, a regimen recommended by the CDC. A 5-day dosage regimen is available for the treatment of community-acquired respiratory-tract and skin and skin-structure infections caused by susceptible organisms. Azithromycin provides short-duration, high-compliance, cost-effective regimens that should improve outcomes.

Murine thrombopoietin mRNA levels are modulated by platelet count.

The activity of the c-Mpl ligand hematopoietic progenitors meets criteria expected for thrombopoietin (TPO). Bio-assays have shown that blood TPO levels are inversely related to platelet mass. We sought to identify the molecular basis for this regulation. To determine if TPO mRNA levels respond to platelet demand, RNA from selected organs of mice with high, normal or low platelet counts was subjected to semiquantitative reverse transcriptase-polymerase chain reaction. Although no differences in TPO mRNA levels between control and treated mice could be detected in liver or kidney, TPO-specific bands were more intense after 25 to 30 polymerase chain reaction cycles in marrow-derived mRNA from thrombocytopenic mice. The TPO-specific bands were less intense in thrombocytotic mouse marrow and spleen than control mouse marrow and spleen after 30 cycles. These data support the hypothesis that TPO levels are regulated, at least in part, by modulating mRNA levels in response to platelet demand.

Interleukin-4 induces endothelial vascular cell adhesion molecule-1 (VCAM-1) by an NF-kappa b-independent mechanism.

While all features of the inflammatory response induced by IL-1 are not observed following IL-4 stimulation, suboptimal concentrations both cytokines result in synergistic VCAM-1 expression in HUVEC. We have shown that, while IL-1 stimulated HUVEC express GM-CSF, tissue factor and VCAM-1, only VCAM-1 is detectable after exposure to IL-4. While kB was found essential for both basal and IL-1-mediated activity of VCAM-1, IL-4 induction was kB-independent. Inducible kB-binding proteins were identified in IL-1-, but not IL-4-stimulated nuclear extracts. Our results indicate that IL-4 exerts its transcriptional effects on the VCAM-1 gene through element(s) which do not require kB.

Multicenter controlled trial comparing ceftibuten with amoxicillin/clavulanate in the empiric treatment of acute otitis media. Members of the Ceftibuten Otitis Media United States Study Group.

The efficacy and safety of ceftibuten (9 mg/kg daily for 10 days) were compared with those of amoxicillin/clavulanate (Augmentin 40 mg/kg/day given every 8 hours for 10 days) in the empiric treatment of acute otitis media in children. This was a multicenter, investigator-blinded study with 1:1 randomization. Overall clinical response and signs and symptoms of otitis were collected prospectively pretreatment, 3 to 5 days during treatment, 1 to 3 days post-treatment and at 2- to 4-week follow-up. In addition to spontaneous reports of other adverse events, gastrointestinal adverse events were prospectively elicited at each visit. Two hundred ninety-six patients (146 ceftibuten and 150 amoxicillin/clavulanate) were treated with at least 1 dose of study medication. Compliance with dosing was assessable with weight of drug consumed in 127 patients in each treatment group. Five percent (6 of 127) of ceftibuten patients and 11% (14 of 127) of amoxicillin/clavulanate patients received < 80% of prescribed drug (P = 0.10) and were therefore not valid. Two hundred twenty-two patients (121 ceftibuten and 101 amoxicillin/clavulanate) received a minimum of 80% of prescribed medication and were compliant with the protocol. Ceftibuten and amoxicillin/clavulanate groups were comparable both for demographic variables and for baseline signs and symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparative efficacy and safety of cefprozil versus penicillin, cefaclor and erythromycin in the treatment of streptococcal pharyngitis and tonsillitis.

Cefprozil is a new oral cephalosporin with an enhanced in vitro spectrum of activity that includes group A beta-hemolytic streptococci (GABHS). Four multicenter randomized clinical trials were conducted to compare the clinical efficacy and safety of cefprozil administered once or twice a day for the treatment of mild to moderate GABHS tonsillitis and pharyngitis. A total of 1597 patients were enrolled in the trials. Patient demographics and severity of infection were similar for all treatment groups. In Study 1, cefprozil administered at 20 mg/kg once daily was clinically, in 68 of 76 patients (89%) and bacteriologically, in 66 of 74 patients (89%) superior to penicillin -51 of 69 (74%) and 46 of 69 (67%)--administered three times a day in patients of two to 12 years of age. In Study 2, the patients enrolled were 13 years of age and older, and cefprozil administered at 20 mg/kg once a day had similar clinical (93% vs. 90%) and bacteriological (95% vs. 94%) response rates as cefaclor administered three times a day. Study 3 demonstrated that cefprozil administered twice daily was similar to penicillin given three times a day, the clinical satisfactory response being 164 of 175 (94%) for cefprozil and 146 of 165 (88%) for penicillin. In Study 4, identical clinical and bacteriologic responses (95%) were observed for cefprozil administered once a day and erythromycin ethylsuccinate administered four times a day in children over two years of age. There were no significant differences in the incidence or severity of drug-related adverse events, which, when reported, were mild and transient.(ABSTRACT TRUNCATED AT 250 WORDS)

Respiratory epithelial cell expression of human transforming growth factor-alpha induces lung fibrosis in transgenic mice.

Increased production of EGF or TGF-alpha by the respiratory epithelial cells has been associated with the pathogenesis of various forms of lung injury. Growth factors and cytokines are thought to act locally, via paracrine and autocrine mechanisms, to stimulate cell proliferation and matrix deposition by interstitial lung cells resulting in pulmonary fibrosis. To test whether TGF-alpha mediates pulmonary fibrotic responses, we have generated transgenic mice expressing human TGF-alpha under control of regulatory regions of the human surfactant protein C (SP-C) gene. Human TGF-alpha mRNA was expressed in pulmonary epithelial cells in the lungs of the transgenic mice. Adult mice bearing the SP-C-TGF-alpha transgene developed severe pulmonary fibrosis. Fibrotic lesions were observed in peribronchial, peribronchiolar, and perivascular regions, as well as subjacent to pleural surfaces. Lesions consisted of fibrous tissue that included groups of epithelial cells expressing endogenous SP-C mRNA, consistent with their identification as distal respiratory epithelial cells. Peripheral fibrotic regions consisted of thickened pleura associated with extensive collagen deposition. Alveolar architecture was disrupted in the transgenic mice with loss of alveoli in the lung parenchyma. Pulmonary epithelial cell expression of TGF-alpha in transgenic mice disrupts alveolar morphogenesis and produces fibrotic lesions mediated by paracrine signaling between respiratory epithelial and interstitial cells of the lung.