A double-blind comparative study of the safety and efficacy of caspofungin versus micafungin in the treatment of candidiasis and aspergillosis.

The safety and efficacy profile of caspofungin and micafungin in Japanese patients with fungal infections were directly compared in this prospective, randomized, double-blind study. The proportion of patients who developed significant drug-related adverse event(s) (defined as a serious drug-related adverse event or a drug-related adverse event leading to study therapy discontinuation) was compared in 120 patients [caspofungin 50 mg, or 50 mg following a 70-mg loading dose on Day 1 (hereinafter, 70/50 mg) group: 60 patients; micafungin 150 mg: 60 patients]. The overall response rate was primarily evaluated in the per-protocol set (PPS) population. The proportion of patients who developed significant drug-related adverse events was 5.0 % (3/60) in the caspofungin group and 10.0 % (6/60) in the micafungin group [95 % confidence interval (CI) for the difference: -15.9 %, 5.2 %]. The favorable overall response in the PPS population for patients with esophageal candidiasis, invasive candidiasis, and chronic pulmonary aspergillosis including aspergilloma was 100.0 % (6/6), 100.0 % (3/3), and 46.7 % (14/30) in the caspofungin group, and 83.3 % (5/6), 100.0 % (1/1), and 42.4 % (14/33) in the micafungin group, respectively. In Japanese patients with Candida or Aspergillus infections, there was no statistical difference in the safety between caspofungin and micafungin. Consistent with other data on these two agents, the efficacy of caspofungin and micafungin was similar.

Surfactant protein C G100S mutation causes familial pulmonary fibrosis in Japanese kindred.

Several mutations in the surfactant protein C (SP-C) gene (SFTPC) have been reported as causing familial pulmonary fibrosis (FPF). However, the genetic background and clinical features of FPF are still not fully understood. We identified one Japanese kindred, in which at least six individuals over three generations were diagnosed with pulmonary fibrosis. We examined the patients radiologically and histopathologically and sequenced their SFTPC and ABCA3 genes. We also established a cell line stably expressing the mutant gene. All the patients had similar radiological and histopathological characteristics. Their histopathological pattern was that of usual interstitial pneumonia, showing numerous fibroblastic foci even in areas without abnormal radiological findings on chest high-resolution computed tomography. No child had respiratory symptoms in the kindred. Sequencing of SFTPC showed a novel heterozygous mutation, c.298G>A (G100S), in the BRICHOS domain of proSP-C, which co-segregated with the disease. However, in the ABCA3 gene, no mutation was found. In vitro expression of the mutant gene revealed that several endoplasmic reticulum stress-related proteins were strongly expressed. The mutation increases endoplasmic reticulum stress and induces apoptotic cell death compared with wild-type SP-C in alveolar type II cells, supporting the significance of this mutation in the pathogenesis of pulmonary fibrosis.

Glomerulocystic kidney disease in an adult with enlarged kidneys: a case report and review of the literature.

We report the case of a 31-year-old male with enlarged kidneys and glomerulocystic kidney disease (GCKD). The patient had no family history of renal disease or other diseases. On initial presentation he complained of poor eyesight, and hypertensive retinopathy and elevated serum creatinine (5.0 mg/dl) were found at that time. Renal biopsy showed cystic dilatation of Bowman's capsule and atrophy of the glomerular tuft. Thus, an adult case of sporadic GCKD was diagnosed. Based on previous reports, kidney size in patients with adult type GCKD varies from small to large. Our patient's kidneys are the largest ever reported (right kidney was 22 cm×10 cm, left kidney was 19 cm×10 cm). A review of the literature dealing with sporadic adult GCKD suggested that it is difficult to diagnose this disease early in its course.

Lactobacillus pentosus strain b240 suppresses pneumonia induced by Streptococcus pneumoniae in mice.

AIMS: Oral administration of probiotics has been known to improve inflammatory responses against infectious diseases. Here, we describe the inhibitory effect of oral intake of heat-killed Lactobacillus pentosus strain b240 (b240) on pneumococcal pneumonia in a murine experimental model. METHOD AND RESULTS: The mice treated with oral b240 for 21 days before Streptococcus pneumoniae infection exhibited prolonged survival time and less body weight loss, compared with saline-treated control mice. Mild pneumonia with significantly reduced secretion of inflammatory cytokines/chemokines according to related mitogen-activated protein kinase signalling molecules (phosphorylated c-Jun N-terminal kinase) was found in b240-treated mice, whereas severe pneumonia with hypercytokinemia was evident in control mice. Prominent reduction in the number of pneumococci and elevated expression of Toll-like receptor 2 and 4 in the lung tissues was concomitantly noted in b240-treated mice. CONCLUSIONS: These findings indicate that b240 has inhibitory effects on pneumococcal pneumonia induced by Strep. pneumoniae infection and improves inflammatory tissue responses, resulting in reduced damages to the respiratory tissues. SIGNIFICANCE AND IMPACT OF THE STUDY: These results demonstrate that oral administration of b240 might protect host animals from Strep. pneumoniae infection by augmentation of innate immune response.

The black mink (Mustela vison). A natural model of immunologic male infertility.

Breeding for fine black fur has generated a colony of mink wherein 20-30% of the males are infertile. Two clinical groups are distinguishable: one being infertile from the start (primary infertility), and the other infertile after one or more years of fertility (secondary fertility). Although the etiology of primary infertility is unknown, the available data indicate that secondary infertility is associated with an autoimmune disease of the testis. Thus, male mink with secondary infertility have (a) higher prevalence and levels of anti-sperm antibody when compared with animals with primary infertility, and the antibody prevalence varies with fur color; (b) severe monocytic orchitis (47%) and/or aspermatogenesis (75%) with negative cultures for bacterial, fungal, mumps, or Coxsackie B viral organisms; (c) massive and extensive granular deposits of mink IgG and/or C3 (71%), typical of immune complexes, along the basal lamina of seminiferous tubules; (d) testes that when eluted with buffer or low pH yielded IgG that was 10-fold enriched in anti-sperm antibody activity as compared with serum IgG; and (e) no immunopathologic evidence of Aleutian mink disease. Although the sperm antigen-antibody complexes in the testis may be important as a pathogenetic mechanism of the testicular disease, there is no correlation between fluorescent anti-sperm antibody detection in the serum and the infertile state. The infertile black mink is a new model of infertility associated with naturally occurring autoimmune disease of the testis.

Aspergillus fumigatus regulates mite allergen-pulsed dendritic cells in the development of asthma.

BACKGROUND: The role in allergic asthma development of the immune response against fungi with concomitant exposure to other common aeroallergens has yet to be determined. In particular, there is little understanding of how inhaled fungi affect the host response to mite allergens. OBJECTIVE: To characterize the in vitro and in vivo effects of concurrent exposure of Aspergillus fumigatus (Af) and Dermatophagoides farinae (Derf) on dendritic cells (DCs) in the development of allergic asthma. METHODS: Murine bone marrow-derived DCs were pulsed with Derf and/or live or heat-inactivated Af. Cytokine production and the expression of pathogen recognition receptors (PRRs) were determined in vitro. Subsequently, these DCs were inoculated into the airway of naïve mice to assess the development of allergic airway inflammation in vivo. The effect of antibodies against PRRs was also evaluated. RESULTS: Live Af significantly enhanced IL-10 production and the expression of Toll-like receptor (TLR) 2 and Dectin-1 in Derf-pulsed DCs. Live Af infection significantly attenuated Derf-pulsed DC-induced allergic airway inflammation in vivo. Antibodies against either TLR2 or Dectin-1 significantly reversed the inhibitory effects of live Af in the development of Derf-pulsed DC-induced allergic airway inflammation. CONCLUSION: Concurrent exposure of DCs to fungal antigens has profound influences on the subsequent mite allergen-induced allergic airway inflammation. Live Af could regulate the functions of airway DCs in the development of mite allergen-induced allergic airway inflammation via regulation of their PRRs. Our results suggest that concurrent exposure to pathogens such as fungi and mite allergens has profound influences on the subsequent allergen-induced allergic airway inflammation. Furthermore, modulating PRR signalling could provide a therapeutic regimen for the development of asthma.

Endoscopic submucosal dissection for early gastric cancer: a large-scale feasibility study.

OBJECTIVE: Endoscopic submucosal dissection (ESD) has the advantage over conventional endoscopic mucosa resection, permitting removal of early gastric cancer (EGC) en bloc, but long-term clinical outcomes remain unknown. A follow-up study on tumour recurrence and survival after ESD was conducted. METHOD: ESD was performed for patients with EGC that fulfilled the expanded criteria: mucosal cancer without ulcer findings irrespective of tumour size; mucosal cancer with ulcer findings

Chromosome evolution in the lizard genus Gekko (Gekkonidae, Squamata, Reptilia) in the East Asian islands.

The lizard genus Gekko consists of over 30 species distributed in Asia and Oceania. From the insular region of East Asia including Japan and Taiwan, 9 species (G. hokouensis, G. japonicus, G. shibatai, G. tawaensis, G. vertebralis,G. yakuensis, and 3 undescribed species) are currently recognized. We made karyological analyses for all these species. Their karyotypes invariably consisted of 2N = 38 chromosomes, but exhibited considerable variation in fundamental number (ranging from 56-62). Substantial chromosomal variation was detected even among populations of a morphologically relatively uniform species, G. hokouensis. Populations of G. hokouensis from the central and northern Ryukyus exhibited prominent female heteromorphic (i.e., ZW type) sex chromosomes. Populations of the southern Ryukyus exclusive of Yonagunijima also had ZW sex chromosomes, whose heteromorphisms were, however, much less prominent. The other G. hokouensis populations including the topotypic continental representatives and the population from Yonagunijima of the southern Ryukyus exhibited no sex chromosome heteromorphism at all. These results strongly suggest that G. hokouensis in the current taxonomic definition actually includes more than 2 species. The process of chromosomal evolution in the East Asian Gekko is hypothesized.

Important roles of tachykinins in the development of allergic nasal hyperresponsiveness in guinea-pigs.

BACKGROUND: Although it has been suggested that the use of tachykinin receptor antagonists might prove to be an effective treatment for allergic rhinitis (AR), they are not used clinically. Therefore, we decided to examine the effects of tachykinin receptor antagonists on AR symptoms in an appropriate experimental model. OBJECTIVE: To evaluate newly developed tachykinin receptor antagonists in a Japanese cedar pollen-induced AR model and to determine their effect on allergen-induced sneezing, nasal blockage, and nasal hyperresponsiveness (NHR). METHODS: Sensitized guinea-pigs were challenged by forced inhalation of pollen once every week. Sneezing and nasal blockage were observed after pollen challenges. NHR (nasal blockage) to an intranasal application of leukotriene D(4) was assessed 2 days after an antigen challenge. We also evaluated whether intranasal dosing with a tachykinin causes NHR. NK(1) and NK(2) receptor antagonists were administered before an intranasal treatment with antigen or tachykinin. Amounts of tachykinins present in nasal cavity lavage fluid were measured by an enzyme immunoassay. RESULTS: Although an NK(1) and NK(2) receptor dual antagonist showed no effect on pollen-induced sneezing and biphasic nasal blockage, it did completely suppress the development of NHR. Experiments using specific NK(1) or NK(2) receptor antagonists revealed that NK(2) receptor activation was preferentially involved in the development of hyperresponsiveness. Increases in the levels of substance P (SP) and neurokinin A (NKA) in the nasal tissue were noted 20 min-1 h after the challenge. Intranasal instillation of either SP or NKA-induced NHR, which was almost completely inhibited by NK(2) receptor antagonists and partially inhibited by NK(1) receptor antagonists. CONCLUSIONS: SP and NKA, which are released early after the challenge, mediate the development of NHR by preferentially activating NK(2) receptors. Therefore, NK(2) receptor antagonists might prove to be effective treatment of AR.

Clinicopathological factors associated with clinical outcomes of endoscopic submucosal dissection for colorectal epithelial neoplasms.

BACKGROUND AND STUDY AIMS: Endoscopic submucosal dissection (ESD) permits removal of colorectal epithelial neoplasms en bloc, but a substantial risk of procedure-related perforation has been reported. We sought to unravel the clinicopathological factors associated with the clinical outcomes of ESD for colorectal epithelial neoplasms in a large series. PATIENTS AND METHODS: ESD was done in 278 patients with 292 colorectal tumors that fulfilled the inclusion criteria. The criteria for ESD were: lesion greater than 20 mm in size, lesion with fibrotic scarring, locally residual colorectal lesion, or invasive carcinoma with slight submucosal penetration. Resection was assessed as en bloc or piecemeal, complete (en bloc with tumor-free lateral and basal margins) or incomplete. Complications including perforation and bleeding were assessed, and factors related to each were analyzed using logistic regression. Patients underwent multiple follow-up endoscopic examinations (mean 4.6; median 4; range 2 - 9; total number 1010). RESULTS: En bloc resection was achieved in 90.1 % of lesions (263/292) and resection was deemed to be complete in 233 (79.8 %). Right-side colonic location and the finding of fibrosis were the significant contributors to incomplete resection. Perforation was seen in 24 cases (8.2 %), and was associated with large tumor size and the presence of fibrosis. When the contributive factors for each were combined, the risks of incomplete resection and perforation were substantially increased. CONCLUSION: The present study provides useful information for predicting risks for incomplete resection and complication in colorectal ESD.

Concentrations of alpha- and beta-defensins in plasma of patients with inflammatory bowel disease.

BACKGROUND: Impaired production/release of defensins, representative endogenous antimicrobial peptides, is associated with the pathogenesis of inflammatory bowel disease (IBD). MATERIAL AND METHODS: Employing in house radioimmunoassay, we examined concentrations of the major forms alpha-defensins, human neutrophil peptides (HNP) 1-3 and human beta-defensin (HBD)-2 in plasma of 55 IBD patients consisting of 29 patients with ulcerative colitis (UC) and 26 with Crohn's disease (CD) and 57 controls. RESULTS: The circulating HNP 1-3, but not HBD-2, levels in IBD patients were significantly higher than those in controls. Plasma HNP 1-3 concentrations in CD patients significantly correlated with Crohn's disease activity index, peripheral white blood cell counts, serum CRP values and TNF-alpha levels. CONCLUSIONS: Elevation of circulating alpha-defensins levels is suggestive of their physiopathological roles in IBD. Plasma HNP 1-3 concentrations may be an indicator for CD activity and their association with CRP and TNF-alpha supports a possible association with the inflammatory process.

Association of distinct clinical subsets with myositis-specific autoantibodies towards anti-155/140-kDa polypeptides, anti-140-kDa polypeptides, and anti-aminoacyl tRNA synthetases in Japanese patients with dermatomyositis: a single-centre, cross-sectional study.

OBJECTIVE: To determine the association of distinct clinical subsets with myositis-specific autoantibodies (MSAs) towards anti-155/140-kDa polypeptides [anti-155/140 antibodies (Abs)], anti-140-kDa polypeptides (anti-140 Abs), and anti-aminoacyl tRNA synthetases (ARS Abs) in Japanese patients with dermatomyositis (DM). METHODS: We compared the clinical features and short-term prognoses of 30 DM patients whose serological status included these MSAs. The MSAs were determined by immunoprecipitation. RESULTS: Anti-155/140 Abs (n = 5), anti-140 Abs (n = 8), and anti-ARS Abs (n = 7) did not overlap each other. All of the anti-155/140 Ab-positive patients (n = 5) were complicated by malignancies, as were all of the anti-140 Ab-positive patients (n = 8), who showed rapidly progressive interstitial lung disease (ILD). The survival rate at 6 months from the diagnosis of DM was significantly lower in the anti-140 Ab-positive patients than in the other patients. CONCLUSION: This is the first study to report, in a single cohort of DM patients, that distinct clinical subsets are distributed in an anti-155/140 Ab-positive group, an anti-140 Ab-positive group, or an anti-ARS Ab-positive group. Our data also confirm previous evidence that anti-155/140 Abs are involved in malignancies and that anti-140 Abs are involved in rapidly progressive ILD.

Prevalence of chronic obstructive pulmonary diseases in general clinics in terms of FEV1/FVC.

BACKGROUND: The prevalence of chronic obstructive pulmonary disease (COPD) continues to increase all over the world. Nonetheless, COPD is often misdiagnosed in general clinics because of insufficient use of spirometry. OBJECTIVES: To estimate the prevalence of COPD in general clinics in Japan, we performed spirometry to screen patients who consulted general clinics. METHODS: Patients 40 years of age and older who consulted clinics in Nagasaki Prefecture, Japan, for non-respiratory diseases and who met certain inclusion criteria had their airflow limitation measured by spirometry. We defined COPD as forced expiratory volume in the first second (FEV(1)) over forced vital capacity (FVC) (FEV(1)/FVC) of < 70% in patients without active pulmonary disease, including physician-diagnosed asthma. RESULTS: Of the 1424 patients included in the study, 193 (13.6%) showed airflow limitation. Airflow limitation was significantly related to older age, male gender and cumulative pack-years. FEV(1)/FVC in patients with hypertension and chronic hepatitis were significantly lower than in patients without these diseases when adjusted for age, gender and pack-years. CONCLUSIONS: We showed that there are potentially a number of cases with COPD that are undiagnosed by general physicians in Japan. Measuring airflow limitation by spirometry in smokers with coexisting diseases, such as hypertension and chronic hepatitis, may be very beneficial because COPD is thought to be a systemic disease. The distribution of spirometers to general clinics is definitely needed to detect undiagnosed COPD.

Two-dimensional gel electrophoresis analysis in simultaneous influenza pneumonia and bacterial infection in mice.

Severe pneumonia is found in simultaneous influenza pneumonia and bacterial infection, and suggests a relationship with immunological mechanisms. Here, we performed two-dimensional gel electrophoresis to detect immunological molecules related to the fulminant pneumonia caused by influenza virus and Streptococcus pneumoniae co-infection in mice. We found two spots that were expressed strongly in co-infected mouse lungs, compared with S. pneumoniae or influenza virus singly infected mouse lungs. The spots were analysed by mass spectrometry, and identified as alpha-1 anti-trypsin (A1AT), known as an anti-protease for neutrophil-derived proteolytic enzymes, and creatine kinase, which reflects a greater degree of lung damage and cell death. A1AT expression was increased significantly, and proteolytic enzymes from neutrophils, such as neutrophil elastase, myeloperoxidase and lysozyme, were also secreted abundantly in influenza virus and S. pneumoniae co-infected lungs compared with S. pneumoniae or influenza virus singly infected lungs. These data suggest that A1AT may play a central role as a molecule with broad anti-inflammatory properties, and regulation of the neutrophil-mediated severe lung inflammation is important in the pathogenesis of co-infection with influenza virus and bacteria.

Significance of Tei-index alterations induced by acute preload reduction with hemodialysis.

AIM: The load dependence of Tei-index, an index to estimate combined systolic and diastolic ventricular functions, remains controversial. Moreover, its significance in the setting of acute preload reduction including hemodialysis (HD) remains unknown. Therefore, we examined the significance of the Tei-index in HD patients. PATIENTS AND METHODS: Doppler echocardiographic parameters of 42 patients with normal left ventricular ejection fraction (LVEF) were evaluated before and after HD. Based on the index of body water excess calculated using a Crit-Line monitor, the patients were assigned to Group A (normal hydration approximately overhydration) and Group B (risk of pulmonary congestion). RESULTS: Group A was younger and had a shorter isovolumic relaxation time (IRT) than Group B before HD. Hemodialysis significantly increased the Tei-index of Group A, which was derived from prolonging IRT and isovolumic contraction time and shortening the ejection time without changing LVEF. Changes in the Tei-index (DeltaTei-index) significantly correlated with the rate at which blood volume decreased. They were derived from graphs generated using the Crit-Line monitor. Furthermore, the DeltaTei-index inversely correlated with the Tei-index before HD. CONCLUSION: These findings suggest that the Tei-index is preload-dependent, which is related to changes in volume and speed. Thus, the Tei-index should be cautiously interpreted according to various hemodynamic situations. However, the correlation between the DeltaTei-index and the Tei-index before HD implies that the latter could be a good indicator of effective fluid removal by HD.

Gabexate mesilate suppresses influenza pneumonia in mice through inhibition of cytokines.

Gabexate mesilate is a synthetic protease inhibitor that is effective for acute pancreatitis. The effect of gabexate mesilate in influenza pneumonia in mice was investigated by examining the changes in pulmonary inflammatory cytokines and chemokines. Pathological changes in the lungs of treated mice were extremely mild, compared with changes in infected, untreated mice. Intrapulmonary levels of interleukin-6 and macrophage inflammatory protein-2 decreased in treated mice compared with untreated mice, despite similar viral titres in the lungs. Survival terms for treated and untreated groups were similar. These data indicate that gabexate mesilate has beneficial effects on influenza pneumonia, which may be due to the modulation of inflammatory cytokine/chemokine responses.

Adverse reactions associated with long-term drug administration in Mycobacterium avium complex lung disease.

SETTING: The number of patients with non-tuberculous mycobacterial lung disease (NTM-LD) worldwide has been increasing. Mycobacterium avium complex lung disease (MAC-LD) accounts for 90% of NTM-LD. MAC-LD necessitates long-term treatment, but adverse reactions with long-term administration of drugs are poorly understood. OBJECTIVE: To evaluate adverse reactions with long-term administration of drugs for MAC-LD. DESIGN: We conducted a retrospective single-centre medical chart review of 364 patients administered two or more drugs between July 2010 and June 2015. RESULTS: The prevalence and median time to onset of adverse reactions were as follows: hepatotoxicity 19.5%, 55 days; leucocytopaenia 20.0%, 41 days; thrombocytopaenia 28.6%, 61.5 days; cutaneous reactions 9.3%, 30 days; ocular toxicity 7.7%, 278 days; and increase in serum creatinine 12.4%, 430.5 days. Multivariate analysis showed that rifampicin use was independently associated with thrombocytopaenia, and ethambutol use was independently associated with increases in serum creatinine. CONCLUSION: The main adverse reactions appeared within 3 months after start of treatment. Most patients were able to continue treatment with liver-supporting therapy, antihistamine agents or desensitisation therapy; however, ocular toxicity must be monitored for up to 1 year after start of treatment.

Oncolytic virotherapy with an HSV amplicon vector expressing granulocyte-macrophage colony-stimulating factor using the replication-competent HSV type 1 mutant HF10 as a helper virus.

Direct viral infection of solid tumors can cause tumor cell death, but these techniques offer the opportunity to express exogenous factors to enhance the antitumor response. We investigated the antitumor effects of a herpes simplex virus (HSV) amplicon expressing mouse granulocyte-macrophage colony-stimulating factor (mGM-CSF) using the replication-competent HSV type 1 mutant HF10 as a helper virus. HF10-packaged mGM-CSF-expressing amplicon (mGM-CSF amplicon) was used to infect subcutaneously inoculated murine colorectal tumor cells (CT26 cells) and the antitumor effects were compared to tumors treated with only HF10. The mGM-CSF amplicon efficiently replicated in CT26 cells with similar oncolytic activity to HF10 in vitro. However, when mice subcutaneously inoculated with CT26 cells were intratumorally injected with HF10 or mGM-CSF amplicon, greater tumor regression was seen in mGM-CSF amplicon-treated animals. Furthermore, mGM-CSF amplicon treatment prolonged mouse survival. Immunohistochemical analysis revealed increased inflammatory cell infiltration in the solid tumor in the mGM-CSF amplicon-treated animals. These results suggest that expression of GM-CSF enhances the antitumor effects of HF10, and HF10-packaged GM-CSF-expressing amplicon is a promising agent for the treatment of subcutaneous tumors.

Relationship between porotic changes in alveolar bone and spinal osteoporosis.

Epidemiological studies have shown that post-menopausal women who do not use an estrogen supplement have fewer teeth than those who do. We hypothesized that changes in the dentition of post-menopausal women might be due to alveolar bone alterations by estrogen deficiency. To clarify this, we analyzed the microstructural alveolar bone changes in ovariectomized monkeys and compared these with their lumbar bone mineral density. The % of baseline bone mineral density showed a significant decrease in the ovariectomized group as compared with the controls. The second-molar interradicular septa in ovariectomized monkeys showed a significantly decreased nodes number, cortices number, and an increased structural model index value. More pores were seen in the ovariectomized group at the top of the septa. This study demonstrated that, in such monkeys, estrogen deficiency led to fragility of the trabecular structure of the molar alveolar bone, and such fragility was inversely correlated with lumbar bone mineral density.

Fecundity, 17beta-estradiol concentrations and expression of vitellogenin and estrogen receptor genes throughout the ovarian cycle in female Eastern mosquitofish from three lakes in Florida.

Previous studies of Eastern mosquitofish in contaminated Lake Apopka, Florida, have documented reduced sperm count and sexual behaviour in males but increased fecundity and liver weight in females, compared to nearby reference lakes. Liver weight can be an indicator of vitellogenin (Vtg) synthesis in fish, such as the mosquitofish. It was therefore hypothesized that estrogenic organochlorine pesticides, present at elevated concentrations in animals from Lake Apopka, could cause the reproductive disorders in males, as well as increase female fecundity. We initiated a test of this hypothesis by examining the relationship between 17beta-estradiol (E2) tissue concentrations, hepatic estrogen receptor alpha (ERalpha) and Vtg A, B and C gene expression and fecundity in sexually mature female Eastern mosquitofish from Lake Apopka and two reference lakes, Lake Woodruff and Lake Orange. We observed that female Eastern mosquitofish from one site in contaminated Lake Apopka produced fewer but bigger embryos than females from the other Lake Apopka site and two reference sites. However, female E2 concentrations and hepatic ERalpha and Vtg A, B and C gene expression showed no overall differences among the four sites, and it is therefore unlikely that the differences in fecundity were caused by estrogenic EDCs. In addition, we observed no induction of any of the three Vtg genes in male Eastern mosquitofish at the two Lake Apopka sites. Based on the well-documented high sensitivity of Vtg induction as a biomarker of xenoestrogen exposure, the evidence from the present study does not support the hypothesis that estrogenic EDCs are affecting reproduction in Eastern mosquitofish living in Lake Apopka. Our experimental design tested specifically for effects mediated via the ER, and e.g. antiandrogenic DDT metabolites might still be of importance for mosquitofish reproduction in Lake Apopka.