Studies on the in vitro formation of periostracum in Helisoma duryi: the influence of the dorsal epithelium on calcium incorporation

1984 ◽  
Vol 62 (6) ◽  
pp. 1177-1180 ◽  
Author(s):  
S. C. Kunigelis ◽  
A. S. M. Saleuddin
Keyword(s):  
Epithelial Tissue ◽  
Whole Brain ◽  
Fast Growing ◽  
Cerebral Ganglia ◽  
Helisoma Duryi ◽  
Shell Deposition ◽  
Slow Growing

Mantle collar tissue was found to produce periostracum when placed in vitro. The rate of shell deposition in vivo was reflected in the in vitro rate of periostracum formation. The addition of whole brain from fast-growing donors to mantle collar from slow-growing animals was found to increase the amount of periostracum produced in vitro. This effect was further enhanced by removing the cerebral ganglia lateral lobes prior to incubation. The presence of dorsal epithelial tissue was found to increase the incorporation of calcium into periostracum formed in vitro.

Mating increases the synthetic activity of the neurosecretory caudodorsal cells of Helisoma duryi (Mollusca: Pulmonata)

1989 ◽  
Vol 67 (10) ◽  
pp. 2363-2367 ◽  
Author(s):  
S. T. Mukai ◽  
A. S. M. Saleuddin
Keyword(s):  
Light Microscope ◽  
Egg Laying ◽  
Microscope Level ◽  
Synthetic Activity ◽  
Leucine Incorporation ◽  
Light Microscope Level ◽  
Cerebral Ganglia ◽  
Helisoma Duryi

In Helisoma duryi, virgin snails lay significantly fewer eggs than mated snails. It is generally accepted that in basommatophoran pulmonates, the neurosecretory caudodorsal cells located in the cerebral ganglia produce a hormone that regulates egg laying. The synthetic activity of the caudodorsal cells in Helisoma has been measured in vitro and in vivo using tritiated leucine. Virgin and castrated snails (reproductively inactive) showed significantly reduced levels of [3H]leucine incorporation compared with first-mated snails (24 and 48 h postmating). This increase in synthetic activity following mating was corroborated by autoradiography at the light microscope level which localized transport of caudodorsal cell neurosecretory proteins to the cerebral commissure, the neurohaemal area. Mating triggers an increase in synthetic activity of the caudodorsal cells.

scholarly journals Biofilm formation in the lung contributes to virulence and drug tolerance of Mycobacterium tuberculosis

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Poushali Chakraborty ◽  
Sapna Bajeli ◽  
Deepak Kaushal ◽  
Bishan Dass Radotra ◽  
Ashwani Kumar
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Immune System ◽  
Biofilm Formation ◽  
Antimycobacterial Activity ◽  
Drug Tolerance ◽  
Host Immune System ◽  
Tissue Sections ◽  
Slow Growing

AbstractTuberculosis is a chronic disease that displays several features commonly associated with biofilm-associated infections: immune system evasion, antibiotic treatment failures, and recurrence of infection. However, although Mycobacterium tuberculosis (Mtb) can form cellulose-containing biofilms in vitro, it remains unclear whether biofilms are formed during infection in vivo. Here, we demonstrate the formation of Mtb biofilms in animal models of infection and in patients, and that biofilm formation can contribute to drug tolerance. First, we show that cellulose is also a structural component of the extracellular matrix of in vitro biofilms of fast and slow-growing nontuberculous mycobacteria. Then, we use cellulose as a biomarker to detect Mtb biofilms in the lungs of experimentally infected mice and non-human primates, as well as in lung tissue sections obtained from patients with tuberculosis. Mtb strains defective in biofilm formation are attenuated for survival in mice, suggesting that biofilms protect bacilli from the host immune system. Furthermore, the administration of nebulized cellulase enhances the antimycobacterial activity of isoniazid and rifampicin in infected mice, supporting a role for biofilms in phenotypic drug tolerance. Our findings thus indicate that Mtb biofilms are relevant to human tuberculosis.

In vitro and in vivo pathologic effects of Vibrio parahaemolyticus on human epithelial cells

1984 ◽  
Vol 30 (3) ◽  
pp. 381-388 ◽  
Author(s):  
B. R. Merrell ◽  
R. I. Walker ◽  
S. W. Joseph
Keyword(s):  
Epithelial Cells ◽  
Epithelial Tissue ◽  
Ileal Mucosa ◽  
Cytotoxic Factor ◽  
Culture Cells ◽  
Vibrio Parahemolyticus ◽  
Buccal Epithelial Cells ◽  
Culture Supernate

The initial interaction and adherence of Vibrio parahemolyticus to epithelial tissue culture cells, human buccal epithelial cells, and the ileal mucosa of mice were studied. Using scanning electron microscopy, adherent bacteria were observed only on degenerating human embryonic intestinal, HeLa, and buccal cells; healthy normal cells were devoid of bacteria. Sheared V. parahaemolyticus, i.e., lacking flagella, did not adhere to either normal or degenerating tissue cells. Neither ultraviolet-inactivated organisms nor cell-free culture supernate affected the epithelial cells. Similar findings were observed on the mucosa of the ileum in mice inoculated with V. parahaemolyticus. It appears that V. parahaemolyticus possesses a cytotoxic factor which alters epithelial cells. This factor appears to be closely associated with viable organisms and may be a functional element in the adherence process of flagellated V. parahaemolyticus to mammalian epithelial cells.

scholarly journals Adipokines expression and epithelial cell polarity in normal and cancerous breast tissue

2020 ◽  
Vol 41 (10) ◽  
pp. 1402-1408
Author(s):  
Danila Coradini ◽  
Simone Gambazza ◽  
Saro Oriana ◽  
Federico Ambrogi
Keyword(s):  
Cell Polarity ◽  
Protein Level ◽  
Normal Tissue ◽  
Functional Organization ◽  
Epithelial Tissue ◽  
Cancer Etiology ◽  
In Vivo Models ◽  
Glutamyl Transferase

Abstract Cell polarity is crucial for the correct structural and functional organization of epithelial tissue. Its disruption can lead to loss of the apicobasal polarity, alteration in the intracellular components, misregulation of the pathways involved in cell proliferation and cancer promotion. Very recent in vitro/in vivo findings demonstrated that obesity-associated alterations in tissue adipokines protein level negatively affect epithelial polarity. We performed an in silico study to investigate whether such alterations also occur in surgical samples. We aimed to explore the relationship among the expression of the genes coding for leptin (LEP), adiponectin (ADIPOQ), adipokine receptors (LEPR, ADIPOR1 and ADIPOR2), and a panel of polarity-associated genes in normal tissue from breast reduction mammoplasty, and a series of paired samples of histologically normal (HN) tissue and invasive cancer. Results indicated that, in normal tissue, the expression of adipokines and their receptors negatively correlated with that of the polarity-associated genes and GGT1, which codes for γ-glutamyl transferase (GGT) enzyme, a marker of cell distress and membrane disruption. This negative correlation progressively decreased in HN and cancerous tissue, and loss of correlation between ADIPOR2 and polarity-associated genes appeared the most noticeable alteration. Given the growing role of obesity in breast cancer etiology and the opposite action of leptin and adiponectin in epithelial tissue remodeling, ADIPOR2 loss could be addressed as a key mechanism leading to an unbalanced leptin stimulatory activity, subsequent cell polarity disruption and eventually tumor initiation, a finding that requires to be confirmed also at the protein level and with in vivo models.

MR Imaging in Cerebral Gliomas

1994 ◽  
Vol 35 (5) ◽  
pp. 495-505 ◽  
Author(s):  
M. Tovi ◽  
M. Hartman ◽  
A. Lilja ◽  
A. Ericsson
Keyword(s):  
Mr Imaging ◽  
Malignant Gliomas ◽  
Close Correlation ◽  
Whole Brain ◽  
Tumour Spread ◽  
Cerebral Gliomas ◽  
Degree Of Malignancy ◽  
Periventricular Hyperintensity

A comparative analysis between MR examinations and histopathologic whole-brain sections regarding tumour components was performed in 5 brain specimens from patients with malignant glial brain tumours. All cases were examined with MR imaging in vitro and in 2 cases a close comparison with the MR examinations in vivo was also possible. The most homogeneous hypercellular area in malignant gliomas, giving the highest tumour grade, was not visualised on MR imaging as an isolated entity, either in vitro or in vivo. The most conspicuous tumour component, reflecting the heterogeneity of malignant gliomas, was necrosis. This feature was best depicted in the T2WI. In 4 of 5 cases, distant tumour spread of benign-looking tumour cells was found in areas visualised as normal on T2WI, outside the margins of the peritumoural oedema. In 2 cases, estimation of water content was performed immunohistochemically and a close correlation was found in each case between peritumoural and periventricular hyperintensity on T2WI and areas of pallor on the haematoxylin-eosin-stained whole-brain sections. These areas corresponded to microscopical oedema. MR imaging reflects underlying heterogeneous histopathology in malignant gliomas. The degree of malignancy of the lesion as a whole can thus be assessed by MR imaging. However, the method does not allow malignant gliomas to be correctly delineated.

scholarly journals Antifungal polycyclic tetramate macrolactam HSAF is a novel oxidative stress modulator in Lysobacter enzymogenes

2021 ◽  
Author(s):  
Lingjun Yu ◽  
Hui Li ◽  
Zaichun Zhou ◽  
Fengquan Liu ◽  
Liangcheng Du
Keyword(s):  
Uv Light ◽  
Normal Growth ◽  
Microbial Metabolites ◽  
Characteristic Structure ◽  
Lysobacter Enzymogenes ◽  
Fast Growing ◽  
Oxidative Stresses ◽  
Oxidative Damages

Polycyclic tetramate macrolactams (PoTeM) are a fast-growing family of antibiotic natural products found in phylogenetically diverse microorganisms. Surprisingly, none of the PoTeM had been investigated for potential physiological functions in their producers. Here, we used HSAF (heat-stable antifungal factor), an antifungal PoTeM from Lysobacter enzymogenes, as a model to show that PoTeM forms complexes with iron ion, with a Ka of 2.71*106. The in vivo and in vitro data showed formation of 2:1 and 3:1 complexes between HSAF and iron ions, which were confirmed by molecular mechanical and quantum mechanical calculations. HSAF protected DNA from degradation in high concentrations of iron and H2O2 or under UV radiation. HSAF mutants of L. enzymogenes barely survived under oxidative stresses and markedly increased the production of reactive oxygen species (ROS). Exogenous addition of HSAF into the mutants significantly prevented ROS production and rescued the mutants to normal growth under the oxidative stresses. The results reveal that the function of HSAF is to protect the producer microorganism from oxidative damages, rather than as an iron-acquisition siderophore. The characteristic structure of PoTeM, 2,4-pyrrolidinedione-embedded macrolactam, may represent a new iron-chelating scaffold of microbial metabolites. Together, the study demonstrated a previously unrecognized strategy for microorganisms to modulate oxidative damages to the cells. Importance Polycyclic tetramate macrolactams (PoTeM) are a family of structurally distinct metabolites that have been found in a large number of bacteria. Although PoTeM exhibit diverse therapeutic properties, the physiological function of PoTeM in the producer microorganisms had not been investigated. HSAF from Lysobacter enzymogenes is an antifungal PoTeM that has been subjected to extensive studies for mechanism of biosynthesis, regulation and the antifungal activity. Using HSAF as a model system, we here showed that the characteristic structure of PoTeM, 2,4-pyrrolidinedione-embedded macrolactam, may represent a new iron-chelating scaffold of microbial metabolites. In L. enzymogenes, HSAF functions as a small molecule modulator for oxidative damages caused by iron, H2O2 and UV light. Together, the study demonstrated a previously unrecognized strategy for microorganisms to modulate oxidative damages to the cells. HSAF represents the first member of the fast growing PoTeM family of microbial metabolites whose potential biological function has been studied.

scholarly journals Verification and Establishment of Hydrangea macrophylla ‘Kardinal’ x H. paniculata ‘Brussels Lace’ Interspecific Hybrids

2001 ◽  
Vol 19 (2) ◽  
pp. 85-88 ◽  
Author(s):  
S. M. Reed ◽  
G. L. Riedel ◽  
M. R. Pooler
Keyword(s):  
Rapd Markers ◽  
Leaf Shape ◽  
Leaf Length ◽  
Average Height ◽  
Hydrangea Macrophylla ◽  
Cold Hardy ◽  
Slow Growing ◽  
Putative Hybrids

Abstract An interspecific hydrangea breeding project with the goal of producing cold-hardy hydrangeas with brightly colored flowers was initiated in 1997. The objective of the current study was to transfer Hydrangea macrophylla x H. paniculata plants obtained using ovule culture to in vivo conditions and to verify their hybrid nature. Putative hybrids, representing five H. macrophylla x H. paniculata cultivar combinations, were propagated and rooted in vitro. ‘Kardinal’ x ‘Brussels Lace’ putative hybrids were the only plants that produced roots and survived transfer to the greenhouse. RAPD markers were used to verify hybridity in 13 of these plants, only 5 of which survived. Four of the ‘Kardinal’ x ‘Brussels Lace’ hybrids were greatly reduced in size and slow-growing, having an average height of only 6.4 cm (2.5 in) 8 months after being removed from in vitro conditions. Height, internode length, leaf length and leaf width were approximately six times greater in the remaining ‘Kardinal’ x ‘Brussels Lace’ hybrid than in the four small hybrids. All hybrids resembled H. paniculata in leaf shape and pubescence, and appeared to be less susceptible than H. macrophylla to powdery mildew. Intercrosses between hybrids and backcrosses to parental species will be made when the hybrids flower.

scholarly journals Distinct and interchangeable growing patterns in colorectal cancer stem-like cells are regulated by Musashi-1

2021 ◽  
Author(s):  
Roberto Coppo ◽  
Jumpei Kondo ◽  
Keita Iida ◽  
Mariko Okada ◽  
Kunishige Onuma ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Drug Resistance ◽  
Growth Pattern ◽  
Growth Patterns ◽  
Spheroid Formation ◽  
Fast Growing ◽  
Successful Isolation ◽  
Heterogeneous Features ◽  
Slow Growing

The dynamic and heterogeneous features of cancer stem-like cells (CSCs) have been widely recognized, but their nongenetic cellular plasticity mechanisms remain elusive. By using colorectal cancer organoids, we phenotypically tracked their spheroid formation and growth capacity to a single-cell resolution, and we discovered that the spheroid-forming cells exhibit a heterogeneous growth pattern, consisting of slow- and fast-growing spheroids. The isolated fast-growing spheroids seem to preserve a dual-growing pattern through multiple passages, whereas the isolated slow-growing spheroids are restricted to a slow-growing pattern. Notably, the spheroids of both patterns were tumorigenic. Moreover, the expression of CSC markers varied among the subpopulations with different growth patterns. The isolated slow-growing spheroids adopted the dual-growing pattern by various extrinsic triggers, in which Musashi-1 plays a key role. The slow-growing fraction was resistant to chemotherapy, and its successful isolation can provide an in vitro platform allowing us to elucidate their role in drug resistance.

Mucosal Toxicity Studies of a Gel Formulation of Native Pokeweed Antiviral Protein

2004 ◽  
Vol 32 (2) ◽  
pp. 212-221 ◽  
Author(s):  
Osmond J. D'Cruz ◽  
Barbara Waurzyniak ◽  
Fatih M. Uckun
Keyword(s):  
Clinical Chemistry ◽  
Epithelial Tissue ◽  
Pokeweed Antiviral Protein ◽  
Antiviral Protein ◽  
Vaginal Tissue ◽  
Polycarbonate Membrane ◽  
Membrane Filters ◽  
Histologic Evaluation

Pokeweed antiviral protein (PAP), a 29-kDa plant-derived protein isolated from Phytolacca americana, is a promising nonspermicidal broad-spectrum antiviral microbicide. This study evaluated the mucosal toxicity potential of native PAP in the in vivo rabbit vaginal irritation model as well as the in vitro reconstituted human vaginal epithelial tissue model. Twenty-two New Zealand white rabbits in 4 subgroups were exposed intravaginally to a gel with and without 0.01, 0.1, or 1.0% native PAP for 10 consecutive days. The dose of PAP used represented nearly 200- to 20,000 times its in vitro anti-HIV IC50 value. Animals were euthanized on day 11 and vaginal tissues were evaluated for histologic and immunohistochemical evidence of mucosal toxicity, cellular inflammation, and hyperplasia. Blood was analyzed for changes in hematology and clinical chemistry profiles. Reconstituted human vaginal epithelial tissue grown on membrane filters was exposed to 0.1, 0.1, or 1.0% native PAP in medium or topically via a gel for 24 hours and tissue damage was evaluated by histological assessment. In the in vivo rabbit vaginal irritation model, half of all PAP-treated rabbits (8/16) exhibited an acceptable range of vaginal mucosal irritation (total score <8 out of a possible 16), whereas nearly a third of PAP-treated rabbits (5/16) developed moderate to marked vaginal mucosal irritation (total score >11). However, no treatment-related adverse effects were seen in hematological or clinical chemistry measurements. Furthermore, in vitro exposure of a 3-dimensional human vaginal tissue grown on polycarbonate membrane filters to identical concentrations of PAP either added to culture medium or applied topically via gel formulation did not result in direct toxicity as determined by histologic evaluation. These findings indicate careful monitoring of vaginal irritation will be required in the clinical development of PAP as a nonspermicidal microbicide.

scholarly journals 4009 Magneto-electric nanoparticles (MENs) cobalt ferrite-barrium titanate (CoFe2O4–BaTiO3) for non-invasive neuromodulation

2020 ◽  
Vol 4 (s1) ◽  
pp. 11-11
Author(s):  
Tyler Nguyen ◽  
Zoe Vriesman ◽  
Peter Andrews ◽  
Sehban Masood ◽  
M Stewart ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Neuronal Activity ◽  
Calcium Imaging ◽  
Post Treatment ◽  
Calcium Signals ◽  
Whole Brain ◽  
Non Invasive ◽  
Cortical Regions

OBJECTIVES/GOALS: Our goal is to develop a non-invasive stimulation technique using magneto-electric nanoparticles (MENs) for inducing and enhancing neuronal activity with high spatial and temporal resolutions and minimal toxicity, which can potentially be used as a more effective approach to brain stimulation. METHODS/STUDY POPULATION: MENs compose of core-shell structures that are attracted to strong external magnetic field (~5000 Gauss) but produces electric currents with weaker magnetic field (~450 Gauss). MENs were IV treated into mice and drawn to the brain cortex with a strong magnetic field. We then stimulate MENs with a weaker magnetic field via electro magnet. With two photon calcium imaging, we investigated both the temporal and spatial effects of MENs on neuronal activity both in vivo and in vitro. We performed mesoscopic whole brain calcium imaging on awake animal to assess the MENs effects. Furthermore, we investigated the temporal profile of MENs in the vasculatures post-treatment and its toxicities to CNS. RESULTS/ANTICIPATED RESULTS: MENs were successfully localized to target cortical regions within 30 minutes of magnetic application. After wirelessly applying ~450 G magnetic field between 10-20 Hz, we observed a dramatic increase of calcium signals (i.e. neuronal excitability) both in vitro cultured neurons and in vivo treated animals. Whole brain imaging of awake mice showed a focal increase in calcium signals at the area where MENs localized and the signals spread to regions further away. We also found MENs stimulatory effects lasted up to 24 hours post treatment. MEN stimulation increases c-Fos expression but resulted in no inflammatory changes, up to one week, by assessing microglial or astrocytes activations. DISCUSSION/SIGNIFICANCE OF IMPACT: Our study shows, through controlling the applied magnetic field, MENs can be focally delivered to specific cortical regions with high efficacy and wirelessly activated neurons with high spatial and temporal resolution. This method shows promising potential to be a new non-invasive brain modulation approach disease studies and treatments.

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