Mechanical forces: The missing link between idiopathic pulmonary fibrosis and lung cancer

Patients with idiopathic pulmonary fibrosis (IPF) have a high risk of developing lung cancer compared with the general population. The morbidity of lung cancer in IPF patient ranges from 3% to 22%, and in some cases exceeds 50%, and these patients have a reduced survival time. However, the mechanisms through which IPF increases the morbidity and mortality in lung cancer remain unclear.By carefully analyzing the pathological features of these two diseases, we uncovered that, first, similar to IPF, lung carcinomas are more frequently found in the peripheral area of the lungs and, second, lung cancers tend to develop from the honeycomb areas in IPF. In accordance with the above pathological features, due to the spatial location, the peripheral areas of the lung experience a high stretch force because the average distance between adjacent alveolar cells in this area tends to be larger than that at the central lung when inflated; furthermore, the honeycomb areas, comprised of condensed fibrous tissue, are characterized by increased stiffness. Both of these pathological features of lung cancer and IPF are coincidentally related to abnormal mechanical forces (stretch and tissue stiffness). Therefore, we believe that the aberrant mechanical forces that are generated in the lung with IPF may contribute to the onset and progression of lung cancer.In this review, we discuss the possible effects of mechanical forces that are generated in IPF on the initiation and progression of lung cancer from the perspective of the hallmarks of cancer, including proliferation, metastasis, angiogenesis, cancer stem cells, immunology, epigenetics, and metabolism, so as to advance our understanding of the pathogenesis of IPF-related lung cancer and to harness these concepts for lung cancer mechanotherapies.     

Examination of Induced Sputum In the Diagnosis of Pneumocystis Carinii Pneumonia

The results of the examination of sputum induced by the inhalation of nebulized hypertonic saline in the diagnosis of Pneumocystis carinii pneumonia (PCP) are presented. In suspected cases of PCP in patients who were either HIV antibody positive or were receiving immunosuppressive therapy, 46 induced sputum specimens were stained using both Grocott's modified Gomori methenamine silver nitrate (GMS) and immunofluorescence staining. In 12 specimens P. carinii cysts were detected by both methods, in four specimens by GMS staining only and in five specimens by immunofluorescence only. The sensitivity of induced sputum examination in the detection of P. carinii cysts was increased by using both of these staining methods on each sputum specimen and the need for more invasive methods of diagnosis was reduced.     

An improved method for primary culture of ovarian androgen-producing cells in serum-free medium: Effect of lipoproteins,insulin, and insulinlike growth factor-I

Summary Although luteinizing hormone (LH) alone stimulates ovarian interstitial cells cultured in serum-free medium to synthesize large amounts of androgens, there seem to be additional factors in vivo that modulate the time course and magnitude of the cellular responses to LH. In an attempt to develop a more nearly physiologic cell culture model, lipoproteins, insulin, and insulinlike growth factor-I (IGF-I) were added to the serum-free medium. The effects of these modifications on androgen biosynthesis by dispersed cells from ovaries of hypophysectomized immature rats cultured in 96-well tissue culture plates were examined. A saturating dose of LH stimulated a 25-fold increase in androsterone synthesis at 2 d, which decreased at 4 and 6 d. Addition of human high density (hHDL) or human low density lipoprotein (hLDL) caused a 2.5-fold increase in LH-stimulated androsterone synthesis. Cells were approximately twice as sensitive to hHDL (ED₅₀=5.5±0.5 μg cholesterol/ml) compared to hLDL (ED₅₀=9.1±1.1 μg cholesterol/ml). Surprisingly, rat HDL caused only a 40% increase in LH-stimulated androsterone synthesis. When insulin alone was added to cells cultured with a saturating dose of LH, there was a 2.8-fold increase in androsterone synthesis. Addition of hHDL and insulin together caused a synergistic increase in LH-stimulated androsterone synthesis. In contrast to hHDL, which did not change the time course of LH-stimulated androsterone production, insulin prolonged maximal LH-stimulated androsterone synthesis at 4 and 6 d. Inasmuch as the ED₅₀ for insulin action (1.3±0.1 μg/ml) was supraphysiologic, the effects of IGF-I on LH-stimulated androgen synthesis were examined. IGF-I mimicked all of the effects of insulin, but at a physiologic concentration (ED₅₀=2.5±0.3 ng/ml). Ovarian cells cultured in serum-free medium supplemented with hHDL and insulin or IGF-I exhibit responses that closely approximate the physiologic responses observed in vivo. These results suggest that lipoproteins and IGF-I are important physiologic stimulators of ovarian theca-interstitial cell androgen biosynthesis which, when added to the serum-free medium, make the cellular responses in this in vitro model more nearly approximate the responses in vivo. This research was supported by research center grant HD 12303 from the National Institute of Child Health and Human Development, Bethesda, MD, and USCD Academic Senate grant RM-169M     

A new device for collection of interstitial water from wetland sediments

A sampler for collection of interstitial water from wetland sediments is described. It differs from other sampling devices because it does not have to be filled with solution to facilitate diffusion, it does not have to be removed from the wetland to collect samples, and it can be used to draw repeated samples over time from identical locations. The device facilitates in situ measurement of a wide range of abiotic parameters such as electrical conductivity, redox potential, and pH in wetland sediments. The device has application in ecological investigations of sediment-borne wildlife diseases, studies of benthic invertebrates, measurement of nutrient exchange, and other aspects of wetland ecology.     

Preliminary data on rotifers in the interstitial of the Ninnescah river, Kansas, USA

One-hundred five rotifer species were identified from a sandy, plains river in Kansas, USA (the Ninnescah river). Of those rotifers identified, eighty occurred only in the interstitial sand, fifty-six in only the flow as plankton, and thirty-one from both habitats. Most species can be characterized as being more commonly found in littoral habitats, and not the interstitial or plankton. Lecane inermis (Bryce, 1892) had the highest density in the hygropsammon interstitial with an average 401 ind. 10 cm⁻³ at 1–3 cm depth in September 1993. New records for the US include Encentrum wiszniewski Wulfert (1939), E. longidens Donner (1943) ant E. (Parencentrum) longipes Wulfert (1960). A small form of Lecane levistyla Olofsson (1917) is further examined and discussed.     

Interstitial noradrenaline concentration of rat hearts as influenced by cellular catecholamine uptake mechanisms

Marked concentration differences of noradrenaline (NA) between the vascular and the interstitial compartment were detected by sampling interstitial transudate from isolated perfused rat hearts. The ratios of vascular/interstitial concentration amounted to 7.4 to 1.3 depending on the concentration of NA administered (3 × 10^–9 to 10^–6 M). These concentration differences were abolished by inhibitors of uptake₁ desipramine (DMI) I and uptake, (O-methyl-isoprenaline (OMI)). Neuronal uptake, was characterized by a K_m of 0.22 mol/l and a V_max of 370 pmol × min^–1 × gWWT^–1, extraneuronal uptake₂ by a K_UPTAKE of = 0.313 min^–4.The apparent permeability surface area (P×S)-product calculated from uptake rate and transcapillary concentration difference was significantly decreased by administrating 100 mol/l (NA) in presence of DMI. A presumed endothelial uptake mechanism contributing to catecholamine translocation was investigated in endothelial cells in culture. These cells showed a specific noradrenaline uptake with a K_m of 4.35 mol/l and a V_max of about 75 pmol × min^–1 x gWWT^–1. Any inhibiton by inhibitors of both of the two noradrenaline uptakes was lacking. The uptake rate of this mechanism is insufficient to contribute to the diffusive conductivity of the capillary wall (P × S-product). We conclude from our investigations on interstitial concentrations of catecholamines and transcapillary concentration differences, that the capillary wall, owing to its metabolic and diffusional characteristics, influences the exchange of catecholamines to a substantial and physiologically relevant extent.     

Long-term follow-up of patients with myocarditis and idiopathic dilated cardiomyopathy after immunomodulatory therapy

Abstract The randomized clinical trial with interferon-α (IFN) or thymic hormones versus conventional therapy was conducted in patients with myocarditis and idiopathic dilated cardiomyopathy (IDC). We enrolled 180 patients to receive IFN (3–5 million units per day) for 3 months, thymomodulin (10 mg three times per week) for 2 months, or conventional therapy alone. Patients were followed-up for 7 years after the end of treatment. Left ventricular function, exercise tolerance and survival rate were significantly better at long-term follow-up in patients treated with IFN or thymomodulin, than in conventionally treated patients. These results implicate that immune modulating therapy might represent important contribution in the treatment of myocarditis and IDC.     

Intertidal interstitial Halicyclops from the Brazilian coast (Copepoda: Cyclopoida)

H. tageae sp. n. and Halicyclops ytororoma sp. n. are described from the intertidal interstitial water of Brazilian beaches. H. tageae is distinguished from all congeneric species by the number of setae on legs 1–4 endopodite 2 (1, 1, 2, 2) and by possessing a reduced inner spine on the leg 5 exopodite. It shares with H. brevispinosus, H. pusillus and H. canui the spine formula 2, 3, 3, 3 on exopodite 3 of swimming legs 1–4. H. ytororoma closely resembles H. gauldi and differs from this species by having 4 setae on leg 1 endopodite 3; H. gauldi has 3 setae on this segment.This is the first record of Halicyclops from marine interstitial water in Brazil.