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1.
J Cell Physiol ; 198(2): 324-32, 2004 Feb.
Article in English | MEDLINE | ID: mdl-14603534

ABSTRACT

It has been recently established that low-frequency electromagnetic field (EMFs) exposure induces biological changes and could be associated with increased incidence of cancer, while the issue remains unresolved as to whether high-frequency EMFs can have hazardous effect on health. Epidemiological studies on association between childhood cancers, particularly leukemia and brain cancer, and exposure to low- and high-frequency EMF suggested an etiological role of EMFs in inducing adverse health effects. To investigate whether exposure to high-frequency EMFs could affect in vitro cell survival, we cultured acute T-lymphoblastoid leukemia cells (CCRF-CEM) in the presence of unmodulated 900 MHz EMF, generated by a transverse electromagnetic (TEM) cell, at various exposure times. We evaluated the effects of high-frequency EMF on cell growth rate and apoptosis induction, by cell viability (MTT) test, FACS analysis and DNA ladder, and we investigated pro-apoptotic and pro-survival signaling pathways possibly involved as a function of exposure time by Western blot analysis. At short exposure times (2-12 h), unmodulated 900 MHz EMF induced DNA breaks and early activation of both p53-dependent and -independent apoptotic pathways while longer continuous exposure (24-48 h) determined silencing of pro-apoptotic signals and activation of genes involved in both intracellular (Bcl-2) and extracellular (Ras and Akt1) pro-survival signaling. Overall our results indicate that exposure to 900 MHz continuous wave, after inducing an early self-defense response triggered by DNA damage, could confer to the survivor CCRF-CEM cells a further advantage to survive and proliferate.


Subject(s)
Apoptosis/radiation effects , Electromagnetic Fields/adverse effects , Gene Expression/radiation effects , Leukocytes/radiation effects , Blotting, Western , Cell Cycle/genetics , Cell Cycle/radiation effects , Cell Division/radiation effects , Humans , Time Factors , Tumor Cells, Cultured , Tumor Suppressor Protein p53/radiation effects
2.
Endocr Res ; 28(3): 155-60, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12489565

ABSTRACT

Amenorrhea is a clinical condition characterized by failure of menarche or by the absence of menstruation for six months in a woman with previous periodic menses. We report a first case of a 30 year-old woman affected by polycystic ovarian disease (PCOD) whose amenorrhea ceased after a 6-month combination treatment with cyclic estradiol-norethisterone acetate. After the withdrawal of the hormone therapy, a stable recovery of periodic menses was observed. We describe a second case of a 23 year-old woman whose amenorrhea was caused by a hypogonadotropic hypogonadism due to a non-functioning pituitary adenoma. After the administration of the previously described therapy both a disappearance of the adenoma and a recover of periodic menses were observed. We hypothesized that the outcomes in our cases could be the consequence of a balancing action induced by the exogenous hormone administration. The exogenous hormones may have reset the feedback between the hypothalamus and pituitary gland through mimicking the physiological hormones pattern of the 28-day cycle.


Subject(s)
Adenoma/complications , Amenorrhea/drug therapy , Estradiol/administration & dosage , Norethindrone/analogs & derivatives , Norethindrone/administration & dosage , Pituitary Neoplasms/complications , Polycystic Ovary Syndrome/complications , Adenoma/physiopathology , Adult , Amenorrhea/etiology , Drug Administration Schedule , Drug Therapy, Combination , Feedback , Female , Humans , Hypogonadism/complications , Hypothalamus/drug effects , Hypothalamus/physiopathology , Norethindrone Acetate , Ovary/physiopathology , Pituitary Gland/drug effects , Pituitary Gland/physiopathology , Pituitary Neoplasms/physiopathology , Polycystic Ovary Syndrome/physiopathology
3.
J Cell Physiol ; 189(1): 34-44, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11573202

ABSTRACT

It has been recently reported that retinoblastoma family proteins suppress cell growth by regulating not only E2F-dependent mRNA transcription but also rRNA and tRNA transcription and, through HDAC1 recruitment, chromatin packaging. In the present study we report data showing that these various control strategies are correlated, at least in part, with nuclear compartmentalization of retinoblastoma proteins. In a first series of experiments, we showed that pRb2/p130 and p107 are not evenly distributed within the nucleus and that cell cycle-dependent binding with E2F4 changes also as a function of their subnuclear localization. Namely, in the nucleoplasm pRb2/p130-E2F4 complexes are more numerous during G0/G1 while in the nucleolus they increase in S phase. Partially different functions for p107 are suggested since p107-E2F4 complexes in the nucleoplasm are more numerous is S phase with respect to G0/G1 and no cell cycle change is observed in the nucleolus. In a second series of experiments we showed that pRb2/p130, p107, E2F4, and pRb2/p130-HDAC1 complexes are all inner nuclear matrix-associated proteins and localize to sites different from pRb/p105 ones. We provide further evidence of multiple and partially distinct retinoblastoma protein family functional roles during cell cycle. Moreover, our data support emerging evidence for functional interrelationships between nuclear structure and gene expression.


Subject(s)
Cell Nucleus/metabolism , Nuclear Proteins/physiology , Phosphoproteins/physiology , Proteins , Cell Compartmentation , Cell Cycle , Cell Division , Cell Nucleus/ultrastructure , DNA-Binding Proteins/immunology , DNA-Binding Proteins/metabolism , E2F4 Transcription Factor , Histone Deacetylase 1 , Histone Deacetylases/immunology , Histone Deacetylases/metabolism , Humans , Macromolecular Substances , Microscopy, Immunoelectron , Models, Biological , Nuclear Matrix/metabolism , Phosphoproteins/immunology , Retinoblastoma-Like Protein p107 , Retinoblastoma-Like Protein p130 , Transcription Factors/immunology , Transcription Factors/metabolism , Tumor Cells, Cultured
5.
Biomaterials ; 22(15): 2095-105, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11432589

ABSTRACT

A biodegradable non-woven hyaluronic acid polymer scaffold (Hyaff 11) was analysed in vitro as a carrier vehicle for differentiation and mineralization of rat bone marrow stromal cells (BMSC). BMSC were grown on Hyaff 11 in a mineralizing medium in the presence/absence of basic fibroblast growth factor (bFGF). Osteoblastic differentiation was investigated by light and electron microscopy analysing the expression of osteogenic markers: calcium, alkaline phosphatase (AP), osteopontin (OP), bone sialoprotein (BSP) and collagen type 1. We also measured proliferation, AP activity and mRNA expression of AP and osteocalcin (OC). Electron microscopy and Toluidine-blue staining demonstrated that bFGF accelerated (day 20 vs. day 40) and increased mineralization. With bFGF, calcium, OP and BSP were strongly enhanced at day 40, whereas AP decreased. Our in vitro results demonstrate that Hyaff 11 is a useful vehicle for growth, differentiation and mineralization of rat BMSC, and that it permits bone development.


Subject(s)
Bone Marrow Cells/metabolism , Fibroblast Growth Factor 2/pharmacology , Hyaluronic Acid/chemistry , Polymers/chemistry , Stromal Cells/cytology , Alkaline Phosphatase/metabolism , Animals , Biocompatible Materials/chemistry , Calcium/metabolism , Cell Culture Techniques/methods , Cell Division , Cells, Cultured , Collagen Type I/metabolism , Coloring Agents/pharmacology , Culture Media , Integrin-Binding Sialoprotein , Kinetics , Microscopy, Electron , Osteoblasts/cytology , Osteocalcin/metabolism , Osteopontin , Protein Binding , RNA, Messenger/metabolism , Rats , Rats, Inbred F344 , Sialoglycoproteins/metabolism , Time Factors , Tolonium Chloride/pharmacology
6.
Article in English | PAHO-IRIS | ID: phr3-50301

ABSTRACT

Automated indirect immunoperoxidase (avidin-biotin complex) staining using monoclonal antibody #5DF12-3B6, directed against rabies N-protein, was used to detect rabies antigen in tissue samples from animals either naturally or experimentally infected with rabies. This monoclonal antibody recognized all 16 strains of rabies virus tested, as well as rabies-related lyssaviruses including Duvenhage, Lagos Bat, and Mokola. The sample infected with Mokola virus initially showed only weak staining, however, deletion of protease digestion resulted in stronger stain uptake. The test was sensitive and specific, correctly identifying rabies antigen in all but one of the samples tested (37/38), and no apparent staining in any of the negative samples tested (23/23). Tissues from 16 mammalian species were tested, including one rabies infected human tissue sample. The utility of the immunoperoxidase staining method described in this study lies in the ability of one monoclonal to recognize a broad spectrum of lyssaviruses in formalin-fixed tissues.


Subject(s)
Rabies , Rabies virus , Lyssavirus , Antibodies, Monoclonal
7.
Endocr Res ; 25(2): 229-38, 1999 May.
Article in English | MEDLINE | ID: mdl-10382684

ABSTRACT

The aim of the present study was to ascertain whether patients affected by solitary nodular disease of the thyroid or multinodular goiter had a different clinical outcome when treated with suppressive levo-thyroxine (L-T4) therapy rather than replacement L-T4 therapy. We evaluated, by a retrospective analysis, 36 patients who had received TSH-suppressive L-T4 therapy according to TSH value and 55 who had received replacement L-T4 therapy. Fine needle aspiration cytology and thyroid scan after 131I were evaluated before L-T4 administration, while echographic monitoring of number and dimensions of nodules was recorded prior to and during L-T4 treatment. No difference in duration of L-T4 treatment (about 3 years) was registered between the TSH-suppressive therapy group and replacement therapy group. L-T4 administration in a TSH-suppressive or replacement manner did not induce a numerical or volumetric significant decrease of the main nodule or of the total nodule volume. Our data show that chronic TSH-suppressive therapy does not seem to be better than replacement therapy. Moreover, TSH-suppressive therapy presented a higher risk of adverse events than replacement therapy, thus requiring a more careful check with a higher cost of care.


Subject(s)
Goiter, Nodular/drug therapy , Hormone Replacement Therapy , Thyrotropin/blood , Thyroxine/therapeutic use , Adolescent , Adult , Aged , Dose-Response Relationship, Drug , Female , Goiter, Nodular/blood , Goiter, Nodular/pathology , Humans , Male , Middle Aged , Retrospective Studies , Thyroid Hormones/blood , Thyroxine/adverse effects , Thyroxine/pharmacology , Time Factors , Treatment Outcome
8.
Vaccine ; 15(12-13): 1466-72, 1997.
Article in English | MEDLINE | ID: mdl-9302762

ABSTRACT

A raccoon poxvirus (RCNV) recombinant for immunizing against feline panleukopenia and rabies was developed by homologous recombination with a chimeric plasmid for insertional inactivation of the RCNV thymidine kinase gene. The recombinant, RCN-FPV/VP2-rabG, coexpressed the feline panleukopenia virus (FPV) VP2 protein and the rabies virus spike glycoprotein (rabG) under oppositely oriented vaccinia virus P11 promoters. Cats vaccinated subcutaneously with the recombinant showed relatively high neutralizing antibody responses against rabies virus and FPV, and protection against an otherwise virulent FPV challenge with no drop in white blood cell count. Because of containment constraints, no rabies virus challenges were done, but the high concentrations (> 8 IU) of rabies neutralizing antibodies were consistent with levels that usually indicate an ability to counter the infection.


Subject(s)
Antigens, Viral , Feline Panleukopenia Virus/immunology , Glycoproteins/immunology , Orthopoxvirus/genetics , Vaccines, Synthetic/immunology , Viral Envelope Proteins/immunology , Viral Structural Proteins/immunology , Viral Vaccines/immunology , Animals , Antibodies, Viral/blood , Cats , Rabies Vaccines/immunology , Raccoons
9.
Endocr Res ; 23(3): 205-12, 1997 Aug.
Article in English | MEDLINE | ID: mdl-9378107

ABSTRACT

Hyperparathyroidism due to an ectopic parathyroid adenoma commonly is revealed by parathyroid hormone (PTH) high serum level and its clinical effects on bone loss. We report a case in which exogenous L-thyroxine side effect on bone in the treatment of thyroid solitary nodule disease produced bone loss in a patient with subclinical hyperparathyroidism due to an ectopic parathyroid adenoma. Our case report suggests the importance of monitoring both clinical symptomatology and calcium and phosphorous serum levels as routine lab investigation in all patients who receive L-thyroxine treatment.


Subject(s)
Adenoma/diagnosis , Osteoporosis/chemically induced , Parathyroid Neoplasms/diagnosis , Thyroxine/adverse effects , Adenoma/complications , Aged , Female , Humans , Hyperparathyroidism/etiology , Parathyroid Neoplasms/complications , Thyroid Gland/diagnostic imaging , Thyroid Gland/pathology , Thyroid Nodule/diagnostic imaging , Thyroid Nodule/drug therapy , Thyroid Nodule/pathology , Thyroxine/therapeutic use , Ultrasonography
11.
Proc Natl Acad Sci U S A ; 92(9): 3908-12, 1995 Apr 25.
Article in English | MEDLINE | ID: mdl-7732005

ABSTRACT

During early development, interactions between the two eyes are critical in the formation of eye-specific domains within the lateral geniculate nucleus and the visual cortex. When monocular enucleation is done early in prenatal life, it induces remarkable anatomical and functional reorganizations of the visual pathways. Behavioral data have shown a loss in sensitivity to low-spatial-frequency gratings in cats. To correlate the behavioral observations with a possible change in the analysis of contrast at the level of primary visual areas we recorded visual evoked potentials at the 17/18 border in two cats enucleated prenatally (gestational age at enucleation, 39-42 days), three neonatal, two control animals, and one animal with a surgical removal of Y-ganglion fibers. Our results show a strong attenuation in the amplitude of response at all contrast values for gratings of low spatial frequency in prenatally enucleated cats, whereas neonatally enucleated and control animals present responses of comparable amplitude. We conclude that the behavioral results reflect the reduced sensitivity for low frequencies of visual cortical neurons. In addition, we define a critical period for the development of the contrast-sensitivity function that seems to be limited to the prenatal gestation period. We suggest that the prenatal interruption of binocular interactions leads to a functional elimination of the Y-ganglion system.


Subject(s)
Evoked Potentials, Visual , Eye Enucleation , Ocular Physiological Phenomena , Vision, Monocular/physiology , Visual Cortex/physiology , Animals , Animals, Newborn , Cats , Eye/embryology , Female , Gestational Age , Pregnancy , Time Factors
12.
Vaccine ; 13(6): 539-49, 1995 Apr.
Article in English | MEDLINE | ID: mdl-7483774

ABSTRACT

A canarypox-based (ALVAC) recombinant expressing the rabies G glycoprotein has been utilized to assess in vitro and in vivo biological properties of the canarypox virus vector system. In vitro studies have shown that no replication of the virus can be detected on six human-derived cell lines, nor can the virus be readily adapted to replicate on non-avian cells. Expression of the rabies G can be detected on all cell lines analyzed in the absence of productive viral replication. Analysis of viral-specific DNA accumulation indicated that the block in the replication cycle in the human cell lines analyzed occurred prior to DNA replication. The exact nature of the block, however, remains unknown. The concept of using a non-replicating immunization vehicle has been demonstrated through extensive in vivo studies in a range of species including non-human primates and humans. The results of such in vivo studies have exemplified the safety and immunogenicity of the ALVAC vaccine vector.


Subject(s)
Antigens, Viral , Avipoxvirus/immunology , Canaries/virology , Rabies Vaccines/immunology , Vaccines, Synthetic/immunology , Viral Vaccines/immunology , Animals , Cells, Cultured , Chlorocebus aethiops , DNA, Viral/genetics , DNA, Viral/metabolism , Gene Expression , Genetic Vectors , Glycoproteins/genetics , Glycoproteins/immunology , Guinea Pigs , Humans , Macaca mulatta , Mice , Pan troglodytes , Rabbits , Rabies Vaccines/adverse effects , Rabies Vaccines/genetics , Sensitivity and Specificity , Vaccines, Synthetic/adverse effects , Vaccines, Synthetic/genetics , Vero Cells , Viral Envelope Proteins/genetics , Viral Envelope Proteins/immunology , Viral Vaccines/adverse effects , Viral Vaccines/genetics
13.
Epidemiol Infect ; 113(3): 501-11, 1994 Dec.
Article in English | MEDLINE | ID: mdl-7995360

ABSTRACT

In 1993 New York and Texas each reported a human rabies case traced to a rare variant of rabies virus found in an uncommon species of bat. This study examined the epidemiology of bat rabies in New York State. Demographic, species, and animal-contact information for bats submitted for rabies testing from 1988-92 was analysed. The prevalence of rabies in 6810 bats was 4.6%. Nearly 90% of the 308 rabid bats identified to species were the common big brown bat (Eptesicus fuscus), which comprised 62% of all submissions. Only 25 submissions were silver-haired bats (Lasionycterus noctivagans), the species associated with the two 1993 human cases of rabies, and only two of these bats were positive. Rabies was most prevalent in female bats, in bats submitted because of human [corrected] contact, and in animals tested during September and October. These results highlight the unusual circumstances surrounding the recent human rabies cases in the United States. A species of bat rarely encountered by humans, and contributing little to the total rabies cases in bats, has been implicated in the majority of the indigenously acquired human rabies cases in the United States. The factors contributing to the transmission of this rare rabies variant remain unclear.


Subject(s)
Chiroptera/virology , Rabies virus/isolation & purification , Rabies/veterinary , Animals , Bites and Stings , Chiroptera/classification , Female , Humans , Male , New York/epidemiology , Prevalence , Rabies/epidemiology , Seasons
14.
Proc Natl Acad Sci U S A ; 90(23): 11142-6, 1993 Dec 01.
Article in English | MEDLINE | ID: mdl-8248220

ABSTRACT

Prenatal unilateral enucleation in mammals causes an extensive anatomical reorganization of visual pathways. The remaining eye innervates the entire extent of visual subcortical and cortical areas. Electrophysiological recordings have shown that the retino-geniculate connections are retinotopically organized and geniculate neurones have normal receptive field properties. In area 17 all neurons respond to stimulation of the remaining eye and retinotopy, orientation columns, and direction selectivity are maintained. The only detectable change is a reduction in receptive field size. Are these changes reflected in the visual behavior? We studied visual performance in cats unilaterally enucleated 3 weeks before birth (gestational age at enucleation, 39-42 days). We tested behaviorally the development of visual acuity and, in the adult, the extension of the visual field and the contrast sensitivity. We found no difference between prenatal monocularly enucleated cats and controls in their ability to orient to targets in different positions of the visual field or in their visual acuity (at any age). The major difference between enucleated and control animals was in contrast sensitivity:prenatal enucleated cats present a loss in sensitivity for gratings of low spatial frequency (below 0.5 cycle per degree) as well as a slight increase in sensitivity at middle frequencies. We conclude that prenatal unilateral enucleation causes a selective change in the spatial performance of the remaining eye. We suggest that this change is the result of a reduction in the number of neurones with large receptive fields, possibly due to a severe impairment of the Y system.


Subject(s)
Visual Pathways/growth & development , Visual Perception/physiology , Animals , Cats , Contrast Sensitivity/physiology , Eye Enucleation , Orientation/physiology , Visual Acuity , Visual Fields
18.
Vision Res ; 32(9): 1609-21, 1992 Sep.
Article in English | MEDLINE | ID: mdl-1455733

ABSTRACT

The postnatal development of the temporal properties of the responses to pattern contrast reversal has been studied by recording simultaneously the pattern electroretinogram (PERG) and visual evoked potentials (PVEP) in infants 3-22 weeks old. The stimulus grating (0.5 c/deg) was either reversed in contrast sinusoidally at frequencies 4-10.5 Hz to study the temporal frequency function of steady-state responses, or square-wave reversed at 1 Hz to evaluate the peak latency of transient responses. Developmental changes of the shape and bandwidth of the temporal frequency function of both PERG and PVEP occur post-natally and are particularly pronounced between 13 and 20 weeks from birth, possibly indicating deferred maturation of classes of retinal and central neurons with higher temporal resolution. The peak latency of the PERG decreases during the age period tested to approach adult values towards the end of the fifth month. The rate of decrease of the peak latency of the PERG differs from that of the PVEP, indicating that post-retinal factors contribute largely to the maturation of the latter, especially in the earliest life period.


Subject(s)
Evoked Potentials, Visual/physiology , Pattern Recognition, Visual/physiology , Adult , Aging/physiology , Electroretinography , Female , Humans , Infant , Infant, Newborn , Retina/growth & development , Time Factors
20.
G Chir ; 13(6-7): 347-51, 1992.
Article in Italian | MEDLINE | ID: mdl-1389984

ABSTRACT

The authors, after confirming the social interest of spontaneous pneumothorax, report the results of their experience taking hint from it for some clinical considerations. They mention different therapies suggested for the treatment of this disease; particularly they dwell upon aspiration techniques considered today the treatment of choice in most cases. They conclude affirming that this technique improves results, diminishes risks and complications, and considerably reduces hospitalization.


Subject(s)
Pneumothorax , Adolescent , Adult , Female , Humans , Male , Middle Aged , Pneumothorax/diagnosis , Pneumothorax/therapy
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