Viviana Palma - Academia.edu (original) (raw)

Papers by Viviana Palma

Journal of Medical Case Reports, 2011

Introduction Recent data suggest that mucosal abnormalities can occur even in the duodenum, jejun... more Introduction Recent data suggest that mucosal abnormalities can occur even in the duodenum, jejunum, and distal ileum of cirrhosis patients. We present a case of portal hypertensive enteropathy in a cirrhosis patient shown by capsule endoscopy and the effect of transjugular intrahepatic portosystemic shunt on the ileal pictures. Case presentation An 83-year-old Caucasian woman was admitted to our hospital for anemia and a positive fecal occult blood test. An upper gastrointestinal endoscopy revealed small varices without bleeding signs and hypertensive gastropathy. Colonoscopy was negative. To rule out any other cause of bleeding, capsule endoscopy was performed; capsule endoscopy revealed severe hyperemia of the jejunum-ileal mucosa with active bleeding. Because of the persistence of anemia and the frequent blood transfusions, not responding to β-blocker drugs or octreotide infusion, a transjugular intrahepatic portosystemic shunt was performed. Anemia improved quickly after the transjugular intrahepatic portosystemic shunt, and no further blood transfusion was necessary in the follow-up. The patient developed portal encephalopathy two months later and was readmitted to our department. We repeated the capsule endoscopy that showed a significant improvement of the gastric and ileal mucosa without any signs of bleeding. Conclusion Hypertensive enteropathy is a rare condition, but it seems more common with the introduction of capsule endoscopy in clinical practice. This case shows that the jejunum can be a source of bleeding in cirrhosis patients, and this is the first demonstration of its resolution after transjugular intrahepatic portosystemic shunt placement.

Toxicon, 2004

Diarrhetic shellfish poisoning (DSP) is a gastrointestinal disease caused by fat-soluble polyethe... more Diarrhetic shellfish poisoning (DSP) is a gastrointestinal disease caused by fat-soluble polyether toxins produced by dinoflagellates and accumulated in shellfish. Up to the present, only four fat-soluble polyethers have been known as diarrhetic shellfish toxins. Among them,*** Okadaic acid, Dinophysistoxin-1, Dinophysistoxin-2 and Dinophysistoxin-3. Outbreaks associated with DSP have occurred in the Chilean Patagonia fjords since 1970. Native people, who live in small communities close to the southern fjords, smoke fresh shellfish. During this popular smoking procedure, they impregnate the shellfish with polycyclic aromatic hydrocarbons, as incomplete combustion products, which are potent carcinogenic compounds, this product is sold in local markets without phycotoxins analysis or inclusion in any monitoring program. The present paper shows, DSP phycotoxins quantitation, using high performance liquid chromatography with fluorescent and mass spectrometric detection and the measurements of polycyclic aromatic hydrocarbons by gas chromatography with mass detection, in smoked shellfish samples. The presence of Dinophysistoxin-3, the Dinophysistoxin-1 ester (7-O-acyl-derivatives of dinophysistoxin-1), was assessed in all shellfish samples analyzed. The 7-OH in Dinophysistoxin-1 was esterified with palmitic fatty acid. The shellfish meat contains seven polycyclic aromatic hydrocarbons, among them fluoranthene, phenanthrene, anthracene, pyrene and benzo[a]pyrene. The gas chromatography-mass spectrometry analysis showed four of the six most frequent carcinogenic polycyclic aromatic hydrocarbons reported. The content of benzo[a]pyrene in the Razor Clam and Ribbed Mussel were 78.61 and 4.94 ng/g of shellfish dry weight, respectively. In both cases the benzo[a]pyrene amounts were greater than the acceptable tolerance limits of 1 microg/kg of sample. The Razor Clam samples also show amount further above the maximum label regulated by FAO/WHO (10 microg/kg). The presence of both type of compounds in the smoked shellfish samples analyzed, correspond to a dangerous combination, where the polycyclic aromatic hydrocarbons are carcinogenic compounds by themselves and DTX-1, is a potent tumor promoter.

Breast Journal, 1996

Abstract: Breast conservation surgery is an effective and safe treatment for many breast carcinom... more Abstract: Breast conservation surgery is an effective and safe treatment for many breast carcinomas. It may be possible to further limit the extent of resection (or expand the indication for breast conservation) by the application of preoperative chemotherapy and radiotherapy. We explored the feasibility of this in a pilot study.Seventy-three patients (mean age 48, 63% premenopausal) with confirmed breast cancer, less than 2.5 cm, received chemotherapy (Group A) or chemotherapy plus radiotherapy (Group B) prior to limited resection (tumorectomy). Axillary dissection was always performed. Results: In 6/31 (19%) Group A and 17/42 (40%) Group B patients the tumor was not palpable after preoperative treatment, with complete pathological remission in 1 and 3 cases respectively. Histologic grading, mitosis, cellular alteration, and cellularity evaluations indicated a consistently greater therapeutic effect with chemoradiotherapy than with chemotherapy alone.In conclusion, radiotherapy appears useful in the preoperative treatment of breast cancer and its use in association with various drug combinations should be further explored.

Astrophysical Journal, 2011

Soft gamma repeaters (SGRs) and anomalous X-ray pulsars (AXPs) are thought to be magnetars: neutr... more Soft gamma repeaters (SGRs) and anomalous X-ray pulsars (AXPs) are thought to be magnetars: neutron stars powered by extreme magnetic fields. These rare objects are characterized by repeated and sometimes spectacular gamma-ray bursts. The burst mechanism might involve crustal fractures and excitation of non-radial modes which would emit gravitational waves (GWs). We present the results of a search for GW bursts from six galactic magnetars that is sensitive to neutron star f-modes, thought to be the most efficient GW emitting oscillatory modes in compact stars. One of them, SGR 0501+4516, is likely ~1 kpc from Earth, an order of magnitude closer than magnetars targeted in previous GW searches. A second, AXP 1E 1547.0-5408, gave a burst with an estimated isotropic energy >1044 erg which is comparable to the giant flares. We find no evidence of GWs associated with a sample of 1279 electromagnetic triggers from six magnetars occurring between 2006 November and 2009 June, in GW data from the LIGO, Virgo, and GEO600 detectors. Our lowest model-dependent GW emission energy upper limits for band- and time-limited white noise bursts in the detector sensitive band, and for f-mode ringdowns (at 1090 Hz), are 3.0 × 1044 d 21 erg and 1.4 × 1047 d 21 erg, respectively, where d_{1} = \frac{d_{{0501}}}{1\,{kpc}} and d 0501 is the distance to SGR 0501+4516. These limits on GW emission from f-modes are an order of magnitude lower than any previous, and approach the range of electromagnetic energies seen in SGR giant flares for the first time.

A search for direct pair production of supersymmetric top squarks (t 1 ) is presented, assuming t... more A search for direct pair production of supersymmetric top squarks (t 1 ) is presented, assuming thet 1 decays into a top quark and the lightest supersymmetric particle,χ 0 1, and that both top quarks decay to purely hadronic final states. A total of 16 (4) events are observed compared to a predicted Standard Model background of 13.5 + 3.7 − 3.6 (4.4 + 1.7 − 1.3 ) events in two signal regions based on L dt = 4.7 fb −1 of pp collision data taken at √ s = 7 TeV with the ATLAS detector at the LHC. An exclusion region in thet 1 versusχ 0 1 mass plane is evaluated: 370 < mt 1 < 465 GeV is excluded for mχ0 1 ∼ 0 GeV while mt 1 = 445 GeV is excluded for mχ0 1 ≤ 50 GeV. Technology, Ankara; (e)

En primer lugar quiero agradecer a mis padres, a mi bisabuela, y a mi familia quienes me enseñaro... more En primer lugar quiero agradecer a mis padres, a mi bisabuela, y a mi familia quienes me enseñaron a valorar a la vida, vivirla lo mejor posible y a llegar a las metas sorteando los obstáculos.

Febs Letters, 2010

Keywords: Bergapten Cell survival Apoptosis p53 p21/PCNA a b s t r a c t

Revista Medica De Chile, 2007

This paper is dedicated to the memory of our ATLAS colleagues who did not live to see the full im... more This paper is dedicated to the memory of our ATLAS colleagues who did not live to see the full impact and significance of their contributions to the experiment.

Agustín reyes Ponce ( licenciado fundador de carreras en la universidad iberoamericana, UAP, prof... more Agustín reyes Ponce ( licenciado fundador de carreras en la universidad iberoamericana, UAP, profesor EN LA FCA UNAM y en el IPN.

Journal of Medical Case Reports, 2011

Introduction Recent data suggest that mucosal abnormalities can occur even in the duodenum, jejun... more Introduction Recent data suggest that mucosal abnormalities can occur even in the duodenum, jejunum, and distal ileum of cirrhosis patients. We present a case of portal hypertensive enteropathy in a cirrhosis patient shown by capsule endoscopy and the effect of transjugular intrahepatic portosystemic shunt on the ileal pictures. Case presentation An 83-year-old Caucasian woman was admitted to our hospital for anemia and a positive fecal occult blood test. An upper gastrointestinal endoscopy revealed small varices without bleeding signs and hypertensive gastropathy. Colonoscopy was negative. To rule out any other cause of bleeding, capsule endoscopy was performed; capsule endoscopy revealed severe hyperemia of the jejunum-ileal mucosa with active bleeding. Because of the persistence of anemia and the frequent blood transfusions, not responding to β-blocker drugs or octreotide infusion, a transjugular intrahepatic portosystemic shunt was performed. Anemia improved quickly after the transjugular intrahepatic portosystemic shunt, and no further blood transfusion was necessary in the follow-up. The patient developed portal encephalopathy two months later and was readmitted to our department. We repeated the capsule endoscopy that showed a significant improvement of the gastric and ileal mucosa without any signs of bleeding. Conclusion Hypertensive enteropathy is a rare condition, but it seems more common with the introduction of capsule endoscopy in clinical practice. This case shows that the jejunum can be a source of bleeding in cirrhosis patients, and this is the first demonstration of its resolution after transjugular intrahepatic portosystemic shunt placement.

Toxicon, 2004

Diarrhetic shellfish poisoning (DSP) is a gastrointestinal disease caused by fat-soluble polyethe... more Diarrhetic shellfish poisoning (DSP) is a gastrointestinal disease caused by fat-soluble polyether toxins produced by dinoflagellates and accumulated in shellfish. Up to the present, only four fat-soluble polyethers have been known as diarrhetic shellfish toxins. Among them,*** Okadaic acid, Dinophysistoxin-1, Dinophysistoxin-2 and Dinophysistoxin-3. Outbreaks associated with DSP have occurred in the Chilean Patagonia fjords since 1970. Native people, who live in small communities close to the southern fjords, smoke fresh shellfish. During this popular smoking procedure, they impregnate the shellfish with polycyclic aromatic hydrocarbons, as incomplete combustion products, which are potent carcinogenic compounds, this product is sold in local markets without phycotoxins analysis or inclusion in any monitoring program. The present paper shows, DSP phycotoxins quantitation, using high performance liquid chromatography with fluorescent and mass spectrometric detection and the measurements of polycyclic aromatic hydrocarbons by gas chromatography with mass detection, in smoked shellfish samples. The presence of Dinophysistoxin-3, the Dinophysistoxin-1 ester (7-O-acyl-derivatives of dinophysistoxin-1), was assessed in all shellfish samples analyzed. The 7-OH in Dinophysistoxin-1 was esterified with palmitic fatty acid. The shellfish meat contains seven polycyclic aromatic hydrocarbons, among them fluoranthene, phenanthrene, anthracene, pyrene and benzo[a]pyrene. The gas chromatography-mass spectrometry analysis showed four of the six most frequent carcinogenic polycyclic aromatic hydrocarbons reported. The content of benzo[a]pyrene in the Razor Clam and Ribbed Mussel were 78.61 and 4.94 ng/g of shellfish dry weight, respectively. In both cases the benzo[a]pyrene amounts were greater than the acceptable tolerance limits of 1 microg/kg of sample. The Razor Clam samples also show amount further above the maximum label regulated by FAO/WHO (10 microg/kg). The presence of both type of compounds in the smoked shellfish samples analyzed, correspond to a dangerous combination, where the polycyclic aromatic hydrocarbons are carcinogenic compounds by themselves and DTX-1, is a potent tumor promoter.

Breast Journal, 1996

Abstract: Breast conservation surgery is an effective and safe treatment for many breast carcinom... more Abstract: Breast conservation surgery is an effective and safe treatment for many breast carcinomas. It may be possible to further limit the extent of resection (or expand the indication for breast conservation) by the application of preoperative chemotherapy and radiotherapy. We explored the feasibility of this in a pilot study.Seventy-three patients (mean age 48, 63% premenopausal) with confirmed breast cancer, less than 2.5 cm, received chemotherapy (Group A) or chemotherapy plus radiotherapy (Group B) prior to limited resection (tumorectomy). Axillary dissection was always performed. Results: In 6/31 (19%) Group A and 17/42 (40%) Group B patients the tumor was not palpable after preoperative treatment, with complete pathological remission in 1 and 3 cases respectively. Histologic grading, mitosis, cellular alteration, and cellularity evaluations indicated a consistently greater therapeutic effect with chemoradiotherapy than with chemotherapy alone.In conclusion, radiotherapy appears useful in the preoperative treatment of breast cancer and its use in association with various drug combinations should be further explored.

Astrophysical Journal, 2011

Soft gamma repeaters (SGRs) and anomalous X-ray pulsars (AXPs) are thought to be magnetars: neutr... more Soft gamma repeaters (SGRs) and anomalous X-ray pulsars (AXPs) are thought to be magnetars: neutron stars powered by extreme magnetic fields. These rare objects are characterized by repeated and sometimes spectacular gamma-ray bursts. The burst mechanism might involve crustal fractures and excitation of non-radial modes which would emit gravitational waves (GWs). We present the results of a search for GW bursts from six galactic magnetars that is sensitive to neutron star f-modes, thought to be the most efficient GW emitting oscillatory modes in compact stars. One of them, SGR 0501+4516, is likely ~1 kpc from Earth, an order of magnitude closer than magnetars targeted in previous GW searches. A second, AXP 1E 1547.0-5408, gave a burst with an estimated isotropic energy >1044 erg which is comparable to the giant flares. We find no evidence of GWs associated with a sample of 1279 electromagnetic triggers from six magnetars occurring between 2006 November and 2009 June, in GW data from the LIGO, Virgo, and GEO600 detectors. Our lowest model-dependent GW emission energy upper limits for band- and time-limited white noise bursts in the detector sensitive band, and for f-mode ringdowns (at 1090 Hz), are 3.0 × 1044 d 21 erg and 1.4 × 1047 d 21 erg, respectively, where d_{1} = \frac{d_{{0501}}}{1\,{kpc}} and d 0501 is the distance to SGR 0501+4516. These limits on GW emission from f-modes are an order of magnitude lower than any previous, and approach the range of electromagnetic energies seen in SGR giant flares for the first time.

A search for direct pair production of supersymmetric top squarks (t 1 ) is presented, assuming t... more A search for direct pair production of supersymmetric top squarks (t 1 ) is presented, assuming thet 1 decays into a top quark and the lightest supersymmetric particle,χ 0 1, and that both top quarks decay to purely hadronic final states. A total of 16 (4) events are observed compared to a predicted Standard Model background of 13.5 + 3.7 − 3.6 (4.4 + 1.7 − 1.3 ) events in two signal regions based on L dt = 4.7 fb −1 of pp collision data taken at √ s = 7 TeV with the ATLAS detector at the LHC. An exclusion region in thet 1 versusχ 0 1 mass plane is evaluated: 370 < mt 1 < 465 GeV is excluded for mχ0 1 ∼ 0 GeV while mt 1 = 445 GeV is excluded for mχ0 1 ≤ 50 GeV. Technology, Ankara; (e)

En primer lugar quiero agradecer a mis padres, a mi bisabuela, y a mi familia quienes me enseñaro... more En primer lugar quiero agradecer a mis padres, a mi bisabuela, y a mi familia quienes me enseñaron a valorar a la vida, vivirla lo mejor posible y a llegar a las metas sorteando los obstáculos.

Febs Letters, 2010

Keywords: Bergapten Cell survival Apoptosis p53 p21/PCNA a b s t r a c t

Revista Medica De Chile, 2007

This paper is dedicated to the memory of our ATLAS colleagues who did not live to see the full im... more This paper is dedicated to the memory of our ATLAS colleagues who did not live to see the full impact and significance of their contributions to the experiment.

Agustín reyes Ponce ( licenciado fundador de carreras en la universidad iberoamericana, UAP, prof... more Agustín reyes Ponce ( licenciado fundador de carreras en la universidad iberoamericana, UAP, profesor EN LA FCA UNAM y en el IPN.