Pharmacokinetics and tissue disposition of meloxicam in beef calves after repeated oral administration.

The objective of this study was to investigate the pharmacokinetics and tissue disposition of meloxicam after repeated oral administration in calves. Thirteen male British × Continental beef calves aged 4 to 6 months and weighing 297-392 kg received 0.5 mg/kg meloxicam per os once daily for 4 days. Plasma meloxicam concentrations were determined in 8 calves over 6 days after first treatment. Calves were randomly assigned to be euthanized at 5, 10, 15 (n = 3/timepoint), and 19 days (n = 4) after final administration. Meloxicam concentrations were determined in plasma (LOQ= 0.025 µg/mL) and muscle, liver, kidney, and fat samples (LOQ = 2 ng/g) after extraction using validated LC-MS-MS methods. The mean (± SD) Cmax , Cmin , and Caverage plasma meloxicam concentrations were 4.52 ± 0.87 µg/mL, 2.95 ± 0.77 µg/mL, and 3.84 ± 0.81 µg/mL, respectively. Mean (± SD) tissue meloxicam concentrations were highest in liver (226.67 ± 118.16 ng/g) and kidney samples (52.73 ± 39.01 ng/g) at 5 days after final treatment. Meloxicam concentrations were below the LOQ in all tissues at 15 days after treatment. These findings suggest that tissue from meloxicam-treated calves will have low residue concentrations by 21 days after repeated oral administration.

Multigenic control of Listeria monocytogenes susceptibility in mice.

We have used a novel quantitative trait locus model to study the genetics of survival of F2 progeny of susceptible BALB/cByJ and resistant C57BL/6ByJ mice that have been infected with Listeria monocytogenes. This allowed us to map modifiers of L. monocytogenes susceptibility to chromosomes 5 and 13.

Pharmacokinetics of oral meloxicam in ruminant and preruminant calves.

The pharmacokinetics of oral meloxicam has been studied in ruminant, but not preruminant calves. Oral meloxicam was administered at 0.5 mg/kg to six ruminant calves via gavage (RG); to six preruminant calves via gavage (PRG); and to six preruminant calves via suckling in milk replacer (PRF). Plasma drug concentrations, determined over 120-h postadministration, were analyzed by compartmental and noncompartmental methods. The rate of drug absorption was faster (P<0.01) in PRF (0.237±0.0478/h) than RG calves (0.0815±0.0188/h), while absorption in PRG calves (0.153±0.128/h) was not different from other groups. C(max) was lower (P=0.03) in PRF (1.27±0.430 µg/mL) than in PRG calves (2.20±0.467 µg/mL), while C(max) of RG calves (1.95±0.955 µg/mL) was not different from other groups. V/F was higher in PRF calves (365±57 mL/kg) than either PRG (177±63 mL/kg, P<0.01) or RG (232±83 mL/kg, P=0.01) calves. These observations were likely due to differences in bioavailability, physiological maturity, and timing of the drug delivery into different compartments of the ruminant gastrointestinal tract. Results suggest that an adjustment in meloxicam dose may be necessary when administered with milk replacer.

NaPi2b expression in a large surgical Non-Small Cell Lung Cancer (NSCLC) cohort.

BACKGROUND: NaPi2b is a multi-transmembrane sodium-dependent phosphate transporter expressed at normal levels in several organs, including lung. High expression levels have been reported in various tumors including breast, thyroid, ovarian and non-small cell lung cancer. To date evaluation of NaPi2b expression has mostly been restricted to smaller lung cancer cohorts. METHODS: Analyses were performed on archival formalin fixed paraffin embedded primary tumor specimens from patients who had undergone curative intent resection at an Australian tertiary hospital. Tissue microarrays were constructed and stained with the chimeric anti-NaPi2b antibody, MERS67. Semi-quantitative H-scores (range 0 - 300) were calculated for each core tissue sample (H-score = % tumor cells staining for NaPi2b multiplied by staining intensity). An overall average H-score was reported for each specimen, with a cut-off score of 50 considered positive. RESULTS: Of 438 cases, high NaPi2b expression was observed in 151 (34.5%) overall, high expression in 137 of 208 (65.9%) adenocarcinoma cases, and 5 of 179 (2.8%) squamous cases (P < .0001). High NaPi2b expression was associated with female sex, EGFR or KRAS mutation, and TTF1 positivity (adenocarcinoma cases only). High NaPi2b expression was associated with improved overall survival (median 54 vs. 35 months, P = .029). CONCLUSION: High NaPi2b expression was noted in a significant subset of adenocarcinoma cases, and in particular amongst those who were TTF1+, or exhibited EGFR or KRAS mutations. This agrees with earlier reports and highlights the significance that NaPi2b may have a role as a possible target for delivery of cytotoxic agents via antibody-drug conjugate models for some patients with lung adenocarcinoma.

Effect of intravenous sodium salicylate administration prior to castration on plasma cortisol and electroencephalography parameters in calves.

Nociception is an unavoidable consequence of many routine management procedures such as castration in cattle. This study investigated electroencephalography (EEG) parameters and cortisol levels in calves receiving intravenous sodium salicylate in response to a castration model. Twelve Holstein calves were randomly assigned to the following groups: (i) castrated, untreated controls, (ii) 50 mg/kg sodium salicylate IV precastration, were blood sampled at 0, 5, 10, 20, 30, 45, 60, 90, 120, 150, 180, 240, 360, and 480 min postcastration. The EEG recording included baseline, castration, immediate recovery (0-5 min after castration), middle recovery (5-10 min after castration), and late recovery (10-20 min after castration). Samples were analyzed by competitive chemiluminescent immunoassay and fluorescence polarization immunoassay for cortisol and salicylate, respectively. EEG visual inspection and spectral analysis were performed. Statistical analyses included anova repeated measures and correlations between response variable. No treatment effect was noted between the two groups for cortisol and EEG measurements, namely an attenuation of acute cortisol response and EEG desynchronization in sodium salicylate group. Time effects were noted for EEG measurements, cortisol and salicylates levels. Significant correlations between cortisol and EEG parameters were noted. These findings have implications for designing effective analgesic regimens, and they suggest that EEG can be useful to monitor pain attributable to castration.

Duplication, deletion, and polymorphism in the sex-determining region of the mouse Y chromosome.

The ZFY gene in the sex-determining region of the human Y chromosome encodes a "zinc-finger" protein that may be the testis-determining factor, TDF. Although the Y chromosomes of most placental mammals carry a single homolog of ZFY, the mouse Y chromosome has two homologs, both in the sex-determining (Sxr) region. Zfy-1 alone may suffice to determine maleness; Zfy-2 is dispensable, as it was deleted in an Sxr variant that retains sex-determining function but has lost other genes. Both loci mapped near the centromere of the mouse Y chromosome. The Y chromosomes of the subspecies Mus musculus musculus and M. m. domesticus were distinguishable by a Zfy-1 restriction fragment polymorphism, which can be used to study their differing interactions with autosomal sex-determining genes.

Electrophoresis: mathematical modeling and computer simulation.

A mathematical model of electrophoretic separation processes has been developed and adapted for computer simulations. The model is used to predict the characteristic behavior of a variety of electrophoretic techniques from a knowledge of chemical equilibria and physical transport phenomena. The model provides a unifying basis for a rational classification of all electrophoretic processes.

Modeling of electroosmotic and electrophoretic mobilization in capillary and microchip isoelectric focusing.

Our dynamic capillary electrophoresis model which uses material specific input data for estimation of electroosmosis was applied to investigate fundamental aspects of isoelectric focusing (IEF) in capillaries or microchannels made from bare fused-silica (FS), FS coated with a sulfonated polymer, polymethylmethacrylate (PMMA) and poly(dimethylsiloxane) (PDMS). Input data were generated via determination of the electroosmotic flow (EOF) using buffers with varying pH and ionic strength. Two models are distinguished, one that neglects changes of ionic strength and one that includes the dependence between electroosmotic mobility and ionic strength. For each configuration, the models provide insight into the magnitude and dynamics of electroosmosis. The contribution of each electrophoretic zone to the net EOF is thereby visualized and the amount of EOF required for the detection of the zone structures at a particular location along the capillary, including at its end for MS detection, is predicted. For bare FS, PDMS and PMMA, simulations reveal that EOF is decreasing with time and that the entire IEF process is characterized by the asymptotic formation of a stationary steady-state zone configuration in which electrophoretic transport and electroosmotic zone displacement are opposite and of equal magnitude. The location of immobilization of the boundary between anolyte and most acidic carrier ampholyte is dependent on EOF, i.e. capillary material and anolyte. Overall time intervals for reaching this state in microchannels produced by PDMS and PMMA are predicted to be similar and about twice as long compared to uncoated FS. Additional mobilization for the detection of the entire pH gradient at the capillary end is required. Using concomitant electrophoretic mobilization with an acid as coanion in the catholyte is shown to provide sufficient additional cathodic transport for that purpose. FS capillaries dynamically double coated with polybrene and poly(vinylsulfonate) are predicted to provide sufficient electroosmotic pumping for detection of the entire IEF gradient at the cathodic column end.

Phase I trial of docetaxel administered as a 1-hour infusion in children with refractory solid tumors: a collaborative pediatric branch, National Cancer Institute and Children's Cancer Group trial.

PURPOSE: A phase I trial of docetaxel was performed to determine the maximum-tolerated dose (MTD), the dose-limiting toxicities, and the incidence and severity of other toxicities in children with refractory solid tumors. PATIENTS AND METHODS: Forty-four children received 103 courses of docetaxel administered as a 1-hour intravenous infusion every 21 days. Doses ranged from 55 to 150 mg/m2, MTD was defined in heavily pretreated and less heavily pretreated (< or = 2 prior chemotherapy regimens, no prior bone marrow transplantation [BMT], and no radiation to the spine, skull, ribs, or pelvic bones) patients. RESULTS: Dose-related neutropenia was the primary dose-limiting toxicity. The MTD in the heavily pretreated patient group was 65 mg/m2, but the less heavily pretreated patients tolerated a significantly higher dose of docetaxel (maximum-tolerated dose, 125 mg/m2). Neutropenia and constitutional symptoms consisting of malaise, myalgias, and anorexia were the dose-limiting toxicities at 150 mg/m2 in the less heavily pretreated patients. Thrombocytopenia was not prominent, even in patients who experienced dose-limiting neutropenia. Common nonhematologic toxicities of docetaxel included skin rashes, mucositis, and mild elevations of serum transaminases. Neuropathy was uncommon. Peripheral edema and weight gain were observed in two of five patients who received more than three cycles of docetaxel. A complete response (CR) was observed in one patient with rhabdomyosarcoma, a partial response (PR) in one patient with peripheral primitive neuroectodermal tumor (PPNET), and a minimal response (MR) in two patients with PPNET. Three of the four responding patients were treated at doses > or = 100 mg/m2. CONCLUSION: The recommended phase II dose of docetaxel administered as a 1-hour intravenous infusion in children with solid tumors in 125 mg/m2. Because neutropenia was the dose-limiting toxicity and thrombocytopenia was mild, further escalation of the dose should be attempted with granulocyte colony-stimulating factor (G-CSF) support.

Phase I/II study of idarubicin given with continuous infusion fludarabine followed by continuous infusion cytarabine in children with acute leukemia: a report from the Children's Cancer Group.

PURPOSE: The Children's Cancer Group (CCG) undertook a phase I study (CCG-0922) to determine a tolerable dose of idarubicin given with fludarabine and cytarabine in children with relapsed or refractory leukemia. The phase I study was extended to a limited phase II study to assess the activity of this combination in children with acute myelogenous leukemia (AML). PATIENTS AND METHODS: This was a multiinstitutional study within the CCG. Eleven patients were entered onto the phase I study: seven with AML, three with acute lymphoblastic leukemia (ALL), and one with chronic myelogenous leukemia (CML). The maximal-tolerated dose (MTD) of fludarabine and cytarabine determined in a previous study was a fludarabine loading dose (LD) of 10.5 mg/m2 followed by a continuous infusion (CI) of 30.5 mg/m2/24 hours for 48 hours, followed by cytarabine LD 390 mg/m2, then CI 101 mg/m2/h for 72 hours. Idarubicin was given at three dose levels: 6, 9, and 12 mg/m2 intravenously (I.V.) on days 0, 1, and 2. The phase II portion of the trial included 10 additional patients with relapsed or refractory AML. RESULTS: A dose of idarubicin 12 mg/m2/d for 3 days given in combination with fludarabine and cytarabine was tolerated. The major toxicity encountered was hematologic. Nonhematologic toxicities included transaminase elevations, hyperbilirubinemia, and infections. Eight of 10 patients with AML in the phase II portion (12 mg/m2 idarubicin) achieved a complete remission (CR). CONCLUSION: This combination is active in patients with relapsed or refractory AML. The major toxicity encountered is hematologic. This regimen may be useful therapy for AML and should be compared with standard induction therapy in children with newly diagnosed AML.

Phase I trial of docetaxel with filgrastim support in pediatric patients with refractory solid tumors: a collaborative Pediatric Oncology Branch, National Cancer Institute and Children's Cancer Group trial.

Neutropenia is the dose-limiting toxicity of docetaxel in children. This Phase I trial was designed to determine the maximum tolerated dose, the dose-limiting toxicities, and the incidence and severity of other toxicities of docetaxel with filgrastim (G-CSF) support in children with refractory solid tumors. Docetaxel was administered as an i.v. infusion for 1 h every 21 days with a starting dose of 150 mg/m2 and an escalation to 185 mg/m2 and 235 mg/m2 in subsequent patient cohorts. G-CSF (5 microg/kg/day) was administered s.c., starting 48 h after docetaxel and continuing until the post-nadir neutrophil count reached 10,000/microl. Seventeen patients received 27 courses of docetaxel with G-CSF support. Generalized erythematous desquamating skin rash and myalgias were dose-limiting at 235 mg/m2. Localized and generalized rashes were seen at all of the three dose levels. Neutropenia (median nadir, 95/1microl) occurred at all of the dose levels but was brief in duration and not dose-limiting. Thrombocytopenia was minimal (median platelet count nadir, 139,000/microl), and the severity of neutropenia and thrombocytopenia did not seem to be related to the docetaxel dose. Other docetaxel-related toxicities included hemorrhage (associated with mucositis), sepsis, hypersensitivity reaction, transient elevation of liver enzymes, stomatitis, back pain, asthenia, and neuropathy. One minor response was observed in a patient with colon cancer. The maximum tolerated dose of docetaxel with G-CSF support in children is 185 mg/m2, which is 50% higher than the maximum tolerated dose of docetaxel alone in children and 85 % higher than the recommended adult dose.

Phase I study of topotecan administered as a 21-day continous infusion in children with recurrent solid tumors: a report from the Children's Cancer Group.

The purpose of this study was to determine the toxicity, maximum tolerated dose, and pharmacokinetics of a 21-day continuous infusion of topotecan in children with relapsed solid tumors. Fifteen patients received 40 courses of continuous ambulatory infusions of topotecan every 28 days or when there was resolution of hematological toxicity and any grade 2 or greater nonhematological toxicity. The starting dose was 0.4 mg/m2/day. Total topotecan levels were measured on days 1, 7, 14, and 21. Three of four patients who received a starting dose of 0.4 mg/m2/day experienced dose-limiting myelosuppression. At the reduced dose of 0.3 mg/ m2/day, only two of the seven patients experienced dose-limiting myelosuppression. Subsequently, four patients with more limited prior therapy were treated with 0.4 mg/m2/ day; three had dose-limiting myelosuppression. Two patients with a dose-limiting toxicity at 0.4 mg/m2/day tolerated additional courses at 0.3 mg/m2/day. An equal number of patients had grade 4 neutropenia or thrombocytopenia. Other adverse events were rare. Two patients with ependymoma, one with rhabdomyosarcoma, and one with retinoblastoma metastatic to the brain had objective responses. The steady state plasma concentration and clearance of topotecan (Css) was achieved by day 1. Css in six patients with complete data were 1.44 +/- 0.50 and 2.13 +/- 0.83 ng/ml at 0.3 and 0.4 mg/m2/day, respectively. Thus, a 21-day topotecan infusion was well-tolerated at 0.3 mg/m2/day. Myelo-suppression was the dose-limiting toxicity at 0.4 mg/m2/day. The steady state and clearance of topotecan in this study are similar to those reported in adult patients.

Autocrine interactions of keratinocyte growth factor, hepatocyte growth factor, and kit-ligand in the regulation of normal ovarian surface epithelial cells.

Ovarian tumors are primarily derived from the layer of epithelium surrounding the ovary termed the ovarian surface epithelium (OSE). Although extensive research has focused on established ovarian tumors, relatively little is known about the normal biology of the OSE that gives rise to ovarian cancer. The local expression and actions of growth factors are likely involved in both normal and tumorigenic OSE biology. The current study investigates the expression and action of keratinocyte growth factor (KGF), hepatocyte growth factor (HGF), and kit-ligand (KL) in normal ovarian surface epithelium (OSE). The actions of various growth factors on KGF, HGF, and KL expression are examined. Observations indicate that freshly isolated normal OSE express the genes for KGF, HGF, and KL and expression is maintained in vitro. KGF messenger RNA expression in OSE was found to be stimulated by KGF and HGF, but not KL. HGF expression in OSE was found to be stimulated by KGF, HGF, and KL. KL expression in OSE was also found to be stimulated by KGF, HGF, and KL. Therefore, the various growth factors can regulate the mRNA expression of each other in OSE. Effects of growth factors on OSE growth were examined. KGF, HGF, and KL stimulated OSE growth to similar levels as the positive control epidermal growth factor. Observations suggest that KGF, HGF, and KL interact to promote OSE growth and growth factor expression. The ability of these growth factors to interact in a positive autocrine feedback loop is postulated to be important for normal OSE biology. Paracrine interactions with the adjacent stromal cells will also be a factor in OSE biology. Abnormal interactions of these growth factors may be involved in the onset and progression of ovarian cancer.

Role of winged helix transcription factor (WIN) in the regulation of Sertoli cell differentiated functions: WIN acts as an early event gene for follicle-stimulating hormone.

Members of the winged helix transcription factor family are known to regulate epithelial cell differentiation by regulating cell-specific gene expression. rWIN is a newly discovered member of the winged helix family shown to be present in the adult rat testis. In the testis the human homolog of rWIN, HFH-11, was localized to the germ cells (i.e. spermatocytes and spermatids) undergoing spermatogenesis. In the present study we show that rWIN is also expressed in testicular Sertoli cells. Sertoli cells are the epithelial component of the seminiferous tubule and provide both the cytoarchitectural support and the microenvironment for developing germ cells. The presence of rWIN in Sertoli cells was confirmed by Northern blot and RT-PCR analysis. The rWIN transcript size in the Sertoli cells was different from the germ cell transcript that is probably due to alternative splicing or modifications of the 3'-untranslated region. At least two spliced variants of rWIN were observed in the Sertoli cells corresponding to the deletion of an exon in the DNA-binding region. Long term stimulation of cultured Sertoli cells with the gonadotropin FSH down-regulated rWIN expression. In contrast, short-term stimulation (2 h) transiently up-regulated rWIN expression. The FSH-induced transient stimulation of rWIN precedes expression of the transferrin gene that is a marker of Sertoli cell differentiation. FSH-induced transferrin promoter activity was inhibited when cultured Sertoli cells were treated with an antisense oligonucleotide to rWIN. Interestingly, the constitutive overexpression of the DNA-binding domain of rWIN also down-regulated transferrin promoter activity. Analysis of the transferrin promoter with various deletion mutations suggested that rWIN acts at an upstream gene of the transferrin promoter. The results indicate that a transient up-regulation of rWIN in part mediates the ability of FSH to activate the transferrin promoter, which can be inhibited with a rWIN antisense oligonucleotide or constitutive expression of the rWIN DNA-binding domain. The current study demonstrates that rWIN acts as an early event gene for FSH actions on Sertoli cells and that rWIN appears to have a role in the regulation of Sertoli cell differentiated functions.

Expression and action of keratinocyte growth factor (KGF) in normal ovarian surface epithelium and ovarian cancer.

The current study investigates the expression and action of keratinocyte growth factor (KGF) in normal ovarian surface epithelium (OSE) and ovarian cancer tissues. Ovarian tumors are primarily derived from the OSE. KGF is a mesenchymal cell-derived growth factor that mediates stromal cell-epithelial cell interactions in a variety of different tissues. Human ovarian tumors from borderline, stage I and stage III cases were found to express KGF protein in the epithelial cell component by immunocytochemical analysis. The stromal cell component of human ovarian tumors contained little or no KGF immunostaining. Normal bovine ovaries have similarities to human ovaries and are used as a model system to investigate normal OSE functions. KGF protein was detected in the OSE from normal human and bovine ovaries by immunocytochemistry. Ovarian stromal tissue contained light but positive KGF immunostaining. RNA was collected from normal bovine OSE and ovarian stromal cells to examine KGF gene expression. KGF transcripts were detected in cultured OSE and stromal cells by Northern blot analysis. In order to examine and quantitate KGF gene expression in freshly isolated versus cultured tissues, a sensitive quantitative RT-PCR assay for KGF was utilized. KGF gene expression was found to be high in freshly isolated OSE, but very low in freshly isolated stroma. Levels of KGF gene expression after culture of OSE and stromal cells increased. Observations indicate that normal OSE express high levels of KGF in vivo and in vitro. Expression of KGF by normal epithelial cells versus stromal cells was unexpected and suggests KGF may be an important autocrine stimulator of OSE. KGF actions on bovine OSE cells were investigated. KGF was found to stimulate the growth of normal OSE cells to the same level as epidermal growth factor. Two ovarian cancer cell lines, SKOV3 and OCC1, were also stimulated to proliferate in response to KGF. Current results demonstrate the production and action of KGF on normal OSE cells and ovarian cancer cells. Observations can be interpreted to suggest that KGF may in part be involved in the growth of ovarian tumors. This appears to be one of the first reports of KGF production by an epithelial cell. The autocrine stimulation of OSE growth by the local production and action of KGF provides insight into how the OSE may develop abnormal growth characteristics involved in the onset and progression of ovarian cancer.

Expression and actions of both the follicle stimulating hormone receptor and the luteinizing hormone receptor in normal ovarian surface epithelium and ovarian cancer.

The ability of gonadotropins to act on and regulate normal ovarian surface epithelial (OSE) cells and ovarian cancer cells was investigated. Bovine OSE was used as a model to study normal OSE. Results demonstrate that follicle stimulating hormone (FSH) and the luteinizing hormone (LH) like molecule, human chorionic gonadotropin (hCG), can both stimulate (3H)-thymidine incorporation into DNA in normal OSE cells. Similar results were obtained using either purified hormones or recombinant human hormones. A human ovarian cancer cell-line OCC1 was also stimulated to grow in response to FSH and hCG, but the growth of a different human ovarian cancer cell-line SKOV3 was not affected. In addition to effects on cell growth, gonadotropins also stimulated growth factor expression. Both FSH and hCG stimulated steady state levels of keratinocyte growth factor (KGF), hepatocyte growth factor (HGF), and kit ligand (KL) mRNA in OSE cells. Previously, KGF, HGF, and KL have been shown to stimulate OSE growth. Both follicle stimulating hormone receptor (FSHR) and luteinizing hormone receptor (LHR) were observed in OSE cells by Northern blot analysis. Reverse transcription polymerase chain reaction (RT-PCR) analysis was performed on fresh and cultured OSE cells. Normal OSE was found to express FSHR and LHR both in vivo and in vitro. The PCR reaction products were sequenced and found to provide a 100% homology with the bovine gonadotropin receptor sequences previously reported. FSHR and LHR transcripts were also detected in gonadotropin responsive OCC1 cells, but not in the gonadotropin insensitive SKOV3 cells. Observations support the hypothesis that gonadotropins may influence some ovarian cancers. In summary, the current study demonstrates the novel observation that both the FSHR and LHR are expressed by bovine OSE and selected ovarian cancers. Interestingly, the actions of FSH and LH to promote OSE growth may in part be mediated indirectly through an elevation in the expression of autocrine growth factors (KGF, HGF, and KL). Ovarian cancer is more common in conditions with elevated gonadotropins such as post-menopausal women. Therefore, gonadotropin actions on the OSE are postulated to be a potential factor in the onset and progression of some ovarian cancers.

Stromal-epithelial interactions in the progression of ovarian cancer: influence and source of tumor stromal cells.

Stromal cells are essential for the progression of many cancers including ovarian tumors. Stromal cell-epithelial cell interactions are important for tumor development, growth, angiogenesis, and metastasis. In the current study, the effects of normal ovarian bovine stromal cells on ovarian tumor progression was investigated. The hypothesis tested is that ovarian stromal cells will alter the onset and progression of ovarian tumors. Conditioned medium from normal bovine ovarian surface stromal cells was found to stimulate the growth of normal ovarian surface epithelium and had no effect on the growth of human tumor cell lines SKOV3 and OCC1. Human ovarian cancer cell lines, SKOV3 and OCC1, were injected subcutaneously into nude mice to examine tumor progression. Tumor growth in the nude mice was dramatically reduced when normal ovarian surface stromal cells were co-injected with SKOV3 or OCC1 cells. Similar results were obtained with normal bovine or human ovarian stromal cells. In contrast, irrelevant testicular stromal cells and epithelial cells had no effect on tumor growth in the nude mouse. Histological examination of these tumors revealed a characteristic stromal cell component adjacent to epithelial cell colonies. Sections of these tumors were hybridized with species specific genomic probes using fluorescence in situ hybridization to identify cell populations. Epithelial cells were shown to be of human origin (i.e. SKOV3 or OCC1), but stromal cells were found to be primarily murine in origin (i.e. host tissue). No detectable bovine cells were observed in the tumors after one week post-injection. Results suggest that stromal cells are an essential component of ovarian tumors. Interestingly, normal ovarian stromal cells had the ability to inhibit tumor growth, but were not able to survive long-term incubation at the tumor site. The developing tumor appears to recruit host (i.e. murine) stromal cells to invade the tumor and support its growth. In summary, normal ovarian stromal cells can inhibit ovarian tumor progression and the developing tumors recruit adjacent host stroma to become "tumor stroma". The tumor stroma likely develop an altered phenotype that cooperates with the tumorigenic epithelial cells to help promote the progression of ovarian cancer.

Papillary immature metaplasia (immature condyloma) of the cervix: a clinicopathologic analysis and comparison with papillary squamous carcinoma.

Papillary immature metaplasia (PIM) is a variant of human papillomavirus (HPV) 6 or 11 infection. PIM resembles an immature metaplasia but has filiform papillae, variable cytological atypia, and, frequently, extension into the endocervical canal. Because the unusual morphology and presentation of PIM may cause confusion between this and other benign and malignant papillary neoplasms, we conducted a clinicopathologic analysis of PIM and compared expression of Ki-67 between PIM, condyloma, and papillary carcinoma. Data on patient age, duration of the lesions, and procedures, including cone biopsy, were obtained. The distribution and intensity of staining for Ki-67 in the epithelium was recorded and compared with both condyloma and papillary carcinoma. HPV typing was performed by polymerase chain reaction (PCR) and restriction fragment length pleomorphism analysis (RFLP). Ten of 13 PIMs were HPV 6/11 positive. Three cases contained areas closely resembling condyloma. Eleven cone biopsies were performed on nine cases. Three were found to have a coexisting high-grade squamous intraepithelial lesion that was either HPV 6/11 negative or contained another HPV type. All PIMs displayed variable staining for Ki-67 with a low index of staining in the mid and upper epithelial layers. In contrast, areas of condyloma had significantly stronger staining in areas with viral cytopathic effect (koilocytosis). Six papillary carcinomas were analyzed and displayed moderate to diffuse staining, including staining of the superficial cell nuclei. PIM is a distinct pathological subset of cervical condyloma that frequently is managed by cone biopsy and may persist. The marked reduction in Ki-67 staining in superficial cell layers distinguishes PIM from some condylomata and most HSILs and papillary carcinomas. Immunostaining thus may be helpful in distinguishing PIM from papillary carcinoma, although the differentiation of the two is best made on morphological grounds.

Intermittent positive pressure ventilation via nasal access in the management of respiratory insufficiency.

These are preliminary observations of the introduction of a new technique of noninvasive positive pressure respiratory support for patients with subacute or chronic respiratory failure. Clinical situations where intubation or tracheostomy may have been performed were managed by intermittent positive pressure ventilation via nasal access (NIPPV) with a CPAP mask, or a custom constructed Vel-Foam nose piece. Four patients were managed at home with the use of portable volume ventilators. One patient employed the technique while hospitalized with subacute respiratory failure. Two patients, otherwise dependent on mouth intermittent positive pressure ventilation (MIPPV) 24 hours a day, received necessary dental care with NIPPV support. In a large population with a decade or more follow-up, MIPPV was shown to be an effective noninvasive technique to support respiration in patients with the most severe paralytic respiratory failure. Preliminary observations suggest that NIPPV may compare favorably with MIPPV and deserves more widespread study and application.

Mathematical modeling and computer simulation of isoelectric focusing with electrochemically defined ampholytes.

A mathematical model of isoelectric focusing at the steady state has been developed for an M-component system of electrochemically defined ampholytes. The model is formulated from fundamental principles describing the components' chemical equilibria, mass transfer resulting from diffusion and electromigration, and electroneutrality. The model consists of ordinary differential equations coupled with a system of algebraic equations. The model is implemented on a digital computer using FORTRAN-based simulation software. Computer simulation data are presented for several two-component systems showing the effects of varying the isoelectric points and dissociation constants of the constituents.