93 research outputs found

    Coxiella burnetii Phagocytosis Is Regulated by GTPases of the Rho Family and the RhoA Effectors mDia1 and ROCK

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    The GTPases belonging to the Rho family control the actin cytoskeleton rearrangements needed for particle internalization during phagocytosis. ROCK and mDia1 are downstream effectors of RhoA, a GTPase involved in that process. Coxiella burnetii, the etiologic agent of Q fever, is internalized by the hostÂŽs cells in an actin-dependent manner. Nevertheless, the molecular mechanism involved in this process has been poorly characterized. This work analyzes the role of different GTPases of the Rho family and some downstream effectors in the internalization of C. burnetii by phagocytic and non-phagocytic cells. The internalization of C. burnetii into HeLa and RAW cells was significantly inhibited when the cells were treated with Clostridium difficile Toxin B which irreversibly inactivates members of the Rho family. In addition, the internalization was reduced in HeLa cells that overexpressed the dominant negative mutants of RhoA, Rac1 or Cdc42 or that were knocked down for the Rho GTPases. The pharmacological inhibition or the knocking down of ROCK diminished bacterium internalization. Moreover, C. burnetii was less efficiently internalized in HeLa cells overexpressing mDia1-N1, a dominant negative mutant of mDia1, while the overexpression of the constitutively active mutant mDia1-ΔN3 increased bacteria uptake. Interestingly, when HeLa and RAW cells were infected, RhoA, Rac1 and mDia1 were recruited to membrane cell fractions. Our results suggest that the GTPases of the Rho family play an important role in C. burnetii phagocytosis in both HeLa and RAW cells. Additionally, we present evidence that ROCK and mDia1, which are downstream effectors of RhoA, are involved in that processFil: Salinas Ojeda, Romina Paola. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Mendoza. Instituto de HistologĂ­a y EmbriologĂ­a de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas MĂ©dicas. Instituto de HistologĂ­a y EmbriologĂ­a de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Ortiz Flores, Rodolfo Matias. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Mendoza. Instituto de HistologĂ­a y EmbriologĂ­a de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas MĂ©dicas. Instituto de HistologĂ­a y EmbriologĂ­a de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Distel, JesĂșs SebastiĂĄn. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Mendoza. Instituto de HistologĂ­a y EmbriologĂ­a de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas MĂ©dicas. Instituto de HistologĂ­a y EmbriologĂ­a de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Aguilera, Milton Osmar. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Mendoza. Instituto de HistologĂ­a y EmbriologĂ­a de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas MĂ©dicas. Instituto de HistologĂ­a y EmbriologĂ­a de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Colombo, Maria Isabel. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Mendoza. Instituto de HistologĂ­a y EmbriologĂ­a de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas MĂ©dicas. Instituto de HistologĂ­a y EmbriologĂ­a de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Beron, Walter. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Mendoza. Instituto de HistologĂ­a y EmbriologĂ­a de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas MĂ©dicas. Instituto de HistologĂ­a y EmbriologĂ­a de Mendoza Dr. Mario H. Burgos; Argentin

    Molecular definition of group 1 innate lymphoid cells in the mouse uterus

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    Determining the function of uterine lymphocytes is challenging because of the rapidly changing nature of the organ in response to sex hormones and, during pregnancy, to the invading fetal trophoblast cells. Here we provide the first genome-wide transcriptome atlas of mouse uterine group 1 innate lymphoid cells (g1 ILCs) at mid-gestation. The composition of g1 ILCs fluctuates throughout reproductive life, with Eomes-veCD49a+ ILC1s dominating before puberty and specifically expanding in second pregnancies, when the expression of CXCR6, a marker of memory cells, is upregulated. Tissue-resident Eomes+CD49a+ NK cells (trNK), which resemble human uterine NK cells, are most abundant during early pregnancy, and showcase gene signatures of responsiveness to TGF-ÎČ, connections with trophoblast, epithelial, endothelial and smooth muscle cells, leucocytes, as well as extracellular matrix. Unexpectedly, trNK cells express genes involved in anaerobic glycolysis, lipid metabolism, iron transport, protein ubiquitination, and recognition of microbial molecular patterns. Conventional NK cells expand late in gestation and may engage in crosstalk with trNK cells involving IL-18 and IFN-Îł. These results identify trNK cells as the cellular hub of uterine g1 ILCs at mid-gestation and mark CXCR6+ ILC1s as potential memory cells of pregnancy.This work was funded by a Wellcome Trust Investigator Award 200841/Z/16/Z, the Centre for Trophoblast Research (CTR), and the Cambridge NIHR BRC Cell Phenotyping Hub to FC, the Associazione Italiana Ricerca per la Ricerca sul Cancro (AIRC) - Special Project 5x1000 no. 9962, AIRC IG 2017 Id.19920 and AIRC 2014 Id. 15283 to LM, and Ministero della Salute RF-2013, GR-2013-02356568 to PV. IF was funded by a CTR PhD fellowship

    Induction of apoptosis of human primary osteoclasts treated with extracts from the medicinal plant Emblica officinalis

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    <p>Abstract</p> <p>Background</p> <p>Osteoclasts (OCs) are involved in rheumatoid arthritis and in several pathologies associated with bone loss. Recent results support the concept that some medicinal plants and derived natural products are of great interest for developing therapeutic strategies against bone disorders, including rheumatoid arthritis and osteoporosis. In this study we determined whether extracts of <it>Emblica officinalis </it>fruits display activity of possible interest for the treatment of rheumatoid arthritis and osteoporosis by activating programmed cell death of human primary osteoclasts.</p> <p>Methods</p> <p>The effects of extracts from <it>Emblica officinalis </it>on differentiation and survival of human primary OCs cultures obtained from peripheral blood were determined by tartrate-acid resistant acid phosphatase (TRAP)-positivity and colorimetric MTT assay. The effects of <it>Emblica officinalis </it>extracts on induction of OCs apoptosis were studied using TUNEL and immunocytochemical analysis of FAS receptor expression. Finally, <it>in vitro </it>effects of <it>Emblica officinalis </it>extracts on NF-kB transcription factor activity were determined by gel shift experiments.</p> <p>Results</p> <p>Extracts of <it>Emblica officinalis </it>were able to induce programmed cell death of mature OCs, without altering, at the concentrations employed in our study, the process of osteoclastogenesis. <it>Emblica officinalis </it>increased the expression levels of Fas, a critical member of the apoptotic pathway. Gel shift experiments demonstrated that <it>Emblica officinalis </it>extracts act by interfering with NF-kB activity, a transcription factor involved in osteoclast biology. The data obtained demonstrate that <it>Emblica officinalis </it>extracts selectively compete with the binding of transcription factor NF-kB to its specific target DNA sequences. This effect might explain the observed effects of <it>Emblica officinalis </it>on the expression levels of interleukin-6, a NF-kB specific target gene.</p> <p>Conclusion</p> <p>Induction of apoptosis of osteoclasts could be an important strategy both in interfering with rheumatoid arthritis complications of the bone skeleton leading to joint destruction, and preventing and reducing osteoporosis. Accordingly, we suggest the application of <it>Emblica officinalis </it>extracts as an alternative tool for therapy applied to bone diseases.</p

    Promoter Hypermethylation-Related Reduced Somatostatin Production Promotes Uncontrolled Cell Proliferation in Colorectal Cancer.

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    BACKGROUND: Somatostatin (SST) has anti-proliferative and pro-apoptotic effects. Our aims were to analyze and compare the SST expression during normal aging and colorectal carcinogenesis at mRNA and protein levels. Furthermore, we tested the methylation status of SST in biopsy samples, and the cell growth inhibitory effect of the SST analogue octreotide in human colorectal adenocarcinoma cell line. METHODS: Colonic samples were collected from healthy children (n1 = 6), healthy adults (n2 = 41) and colorectal cancer patients (CRCs) (n3 = 34) for SST mRNA expression analysis, using HGU133 Plus2.0 microarrays. Results were validated both on original (n1 = 6; n2 = 6; n3 = 6) and independent samples ((n1 = 6; n2 = 6; n3 = 6) by real-time PCR. SST expressing cells were detected by immunohistochemistry on colonic biopsy samples (n1 = 14; n2 = 20; n3 = 23). The effect of octreotide on cell growth was tested on Caco-2 cell line. SST methylation percentage in biopsy samples (n1 = 5; n2 = 5; n3 = 9) was defined using methylation-sensitive restriction enzyme digestion. RESULTS: In case of normal aging SST mRNA expression did not alter, but decreased in cancer (p<0.05). The ratio of SST immunoreactive cells was significantly higher in children (0.70%+/-0.79%) compared to CRC (0%+/-0%) (p<0.05). Octreotide significantly increased the proportion of apoptotic Caco-2 cells. SST showed significantly higher methylation level in tumor samples (30.2%+/-11.6%) compared to healthy young individuals (3.5%+/-1.9%) (p<0.05). CONCLUSIONS: In cancerous colonic mucosa the reduced SST production may contribute to the uncontrolled cell proliferation. Our observation that in colon cancer cells octreotide significantly enhanced cell death and attenuated cell proliferation suggests that SST may act as a regulator of epithelial cell kinetics. The inhibition of SST expression in CRC can be epigenetically regulated by promoter hypermethylation

    Gynecologic oncology group trials of chemotherapy for metastatic and recurrent cervical cancer

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    Because only 16% of patients with metastatic cervical cancer are alive 5 years after diagnosis, the Gynecologic Oncology Group (GOG) has carefully designed and conducted many phase II studies to identify promising drugs. Cisplatin has emerged as the most active single agent with overall response rates of 19%. Recent phase III trials have documented response rates of 27% and 39% when cisplatin has been combined with either paclitaxel or topotecan, respectively. The comparison of cisplatin to cisplatin plus topotecan in GOG-179 has yielded the first study to show a statistically significant impact on the overall response rate, median progression-free survival, and median survival, with all outcome measures favoring the two-drug regimen. Despite these encouraging results, however, most of the responses are partial and of short duration. The need for novel combinations and the implementation of active biologic agents is implicit. The accumulated data in this disease setting, as evidenced by the experience of the GOG, are presented in this review

    Self-Administration of Anesthetic (Propofol and Midazolam) and Psychotropic (Amitriptyline and Zolpidem) Drugs: Recreational Abuse and Suicidal Manner in an Anesthetist

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    After attending this presentation, attendees will understand that forensic investigations are based on a multidisciplinary approach in which autopsy findings and toxicological results often result in association with circumstances and crime scene investigations. This presentation will impact the forensic science community by demonstrating how recreational abuse of anesthetic and sedative agents in health care practitioners, especially anesthesiologists is an increasing event. This presentation will also show an unusual case of suicide in which the manner and means of suicide was dependent upon the occupation of the victim. Presented is a case of a 50-year-old man, anesthetist at the main local hospital, who was found dead in the house where he lived alone since separating from his wife. On the previous evening he was found on the landing’s floor with an occipital bruise injury and treated in the Emergency Department. The next day his brother, alerted by his colleagues that tried in vain to contact him, went to his house. He found that the front door had been left ajar, with a piece of furniture behind it. When he entered the flat, he noticed the corpse of the brother, supine on the living room’s floor near a piece of furniture. There were two drips with intravenous tubes almost empty (approximately 1 ml). One drip was still inserted in the dorsum of the victim’s right hand with tube for intravenous drip totally open. On the glass of this drip there was written “Miclela Caput” (meaning “Caput Mixture,” written incorrectly). On the glass of the other drip there was written “500 TPS+200 DIPR” (meaning Sodium Thiopental+Diprivan). In the house there were some empty blisters of Zolpidem, more than 20 packs of different drugs (some of them empty), an ash-tray containing white liquid, several empty ampoules of Propofol, Midazolam and Thiopental, and several new and used syringes. In the bedroom there were two knapsacks containing pornographic materials and four plastic phalli. External examination revealed abundant livor mortis, numerous recent needle marks with fresh and older hemorrhages in both arms, and a sutured occipital injury. Autopsy and histological findings were pulmonary and brain oedema, moderate fatty liver, acute poly-visceral congestion, hemorrhagic pancreatitis. Systematic toxicological analysis was performed on biological and non biological samples for alcohol, drugs of abuse and pharmaceuticals. Blood toxicological examination by GC/MS revealed lethal concentration of Zolpidem (0.86 ÎŒg/ml) and high therapeutic blood concentrations of Propofol (0.30 ÎŒg/ml), Midazolam (0.08 ÎŒg/ml), Amitriptyline (0.07 ÎŒg/ml), and low concentration of Thiopental (0.03 ÎŒg/ml). Zolpidem was also found in gastric content while Thiopental was found in urine. Hair segment analysis (0 – 2 cm) revealed Propofol (4,7 ÎŒg/mg) and the presence of Zolpidem, Amitriptyline and Ketoprofen. Residual’s toxicological analysis of the inserted drip (“Caput mixture”) revealed Propofol and Midazolam (approximately 1,9 and 0,08 mg/ml). Analysis of the non-inserted drip, showed Propofol and Thiopental (approximately 2 and 5 mg/ml). The low blood concentration of Thiopental suggests a self administration of the non-inserted drip at least 12 hours before death. The blood Propofol level was lower than or within the commonly accepted therapeutic range of 1.3– 6.8 ÎŒg/ml after a standard anesthetic induction dose. Published reports indicate that in most cases, the postmortem Propofol concentrations were at therapeutic levels. It should be pointed out that especially for those agents used in anesthesia; the therapeutic concentrations refer to patients being supported respiratorywise, while in non-supported or non-intubated patients such concentrations may be lethal. Most of those deaths are thought to have occurred because of the rapidity of Propofol’s injection which led to apnea and death. A mere interpretation of the blood and tissue concentrations of Propofol in the toxicological analysis may be of limited diagnostic significance without taking into account the before mentioned reports. Toxicological analysis of hair confirmed the recreational abuse of Propofol. These anesthetic and sedative drugs are often used in combination for anesthesia’s induction. All of these act synergistically in combination and may induce respiratory depression. This effect depends on individual susceptibility, on dose used and, especially for Propofol and Midazolam, infusion’s rapidity. In conclusion, the victim was administered a solution of anesthetic drugs, rapidly infused in a lethal combination and simultaneously a hypnotic drug in lethal dose

    Suicide by self-administration of a drug mixture (propofol, midazolam and zolpidem) in an anesthesiologist: the first case report in Italy

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    The authors report an unusual case of suicide of an anesthesiologist, in which the suicide manner and means depend upon the victim’s occupation. This is the first case report published in Italy of a death involving propofol and other drugs. The anesthesiologist was found dead with an empty drip still inserted in the hand and another one near his body. Forensic and toxicological findings suggested that the cause of death was a respiratory depression due to a self- administration of a rapidly infused lethal drug mixture. Analytical drug quantification was performed by gas chromatography-mass spectrometry (GC-MS). Blood analysis revealed: zolpidem (0.86 ÎŒg/ml), propofol (0.30 ÎŒg/ml), midazolam (0.08 ÎŒg/ml), thiopental (0.03 ÎŒg/ml) and amitriptyline (0.07 ÎŒg/ml). Adipose tissue and hair analysis suggested a previous and repeated use of these drugs verifying the fact that in Italy recreational abuse of anesthetic and sedative agents in health care practitioners is becoming an increasing problem
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