Juan Carlos Martinez | Instituto Tecnológico de Orizaba (original) (raw)

Papers by Juan Carlos Martinez

JOP : Journal of the pancreas, 2003

Pancreatic neoplasms are an uncommon aetiology of acute pancreatitis. Pancreatic neuroendocrine t... more Pancreatic neoplasms are an uncommon aetiology of acute pancreatitis. Pancreatic neuroendocrine tumours are a rare subgroup of pancreatic neoplasms. We report on three patients having acute pancreatitis secondary to pancreatic neuroendocrine tumours, one of them with severe pancreatitis, and review the published cases up to now. Only 22 patients with acute pancreatitis secondary to pancreatic neuroendocrine tumours have been reported (including the present cases). Most of these cases were of non-functioning neoplasms and the course of the pancreatitis tended to be mild. In the most recent reports and in the present cases, the initial diagnostic method was CT scan. Less than half had metastases when the tumour was diagnosed and mortality from these neoplasms reached approximately 50%. Pancreatic neuroendocrine tumours can cause acute pancreatitis even in patients under 50 years of age. On many occasions, the tumours are non-functioning; therefore, acute pancreatitis may be the first ...

JOP : Journal of the pancreas, 2006

Complete agenesis of the dorsal pancreas is an unusual congenital anomaly. Nowadays, the diagnosi... more Complete agenesis of the dorsal pancreas is an unusual congenital anomaly. Nowadays, the diagnosis is based on four imaging studies: transabdominal ultrasonography, computed tomography, magnetic resonance cholangiopancreatography and, the gold-standard, endoscopic retrograde cholangiopancreatography. Sometimes the ability of these studies are limited to distinguishing agenesis of the dorsal pancreas from other congenital abnormalities. Endoscopic ultrasound is a minimally invasive technique which permits us to obtain high resolution images of the pancreatic parenchyma and ductal system. We report the case of a 23-year-old woman with recurrent episodes of acute pancreatitis and non-conclusive classic imaging studies. Complete agenesis of the dorsal pancreas was demonstrated by endoscopic ultrasound. Endoscopic ultrasound may be useful in the diagnosis of agenesis of the dorsal pancreas.

Skeletal Radiology, 2011

Objective To determine the accuracy of guided computed tomography aspiration in the detection of ... more Objective To determine the accuracy of guided computed tomography aspiration in the detection of septic hip prosthesis before surgery. Materials and Methods Sixty-three patients (35 women and 28 men; age range, 29-86 years; mean age, 71 years) with clinically suspected septic hip prosthesis were prospectively studied with independent review board (IRB) approval. Volume and microbiological cultures of aspirated fluid and several computed tomography imaging findings such as periprosthetic fluid collections, prosthetic acetabular malposition, and heterotopic ossification were analyzed. All patients underwent revision surgery and infection was finally diagnosed in 33 patients. Results Statistical comparative analysis was performed comparing computed tomography aspiration and surgical findings (95% CI; level of significance at P=0.05 two-sided) with 70% sensitivity, 100% specificity, 84% accuracy, 100% positive predictive value, and 75% negative predictive value. Using Fisher's exact test, the presence of periprosthetic fluid collections (P=0.001), prosthetic acetabular malposition (P=0.025) and aspirated fluid volume (P=0.009) were significantly higher in infected than in non-infected prostheses, whereas heterotopic ossification was not (P=0.429). Conclusion Computed tomography aspiration is accurate to preoperatively diagnose septic hip prosthesis on the basis of volume and bacterial cultures of aspirated joint fluid. Furthermore, imaging findings such as periprosthetic fluid collections and prosthetic acetabular malposition strongly suggest infected prosthesis.

Pancreatology, 2013

Aims: Pancreatic cancer is the 4th cancer-related death cause in western countries. Early detecti... more Aims: Pancreatic cancer is the 4th cancer-related death cause in western countries. Early detection methods are needed in order to improve its prognosis. Many expectations in this sense have arisen since the discovery of microRNAs (miR). We aimed to analyze the miRNome of PDAC and IPMN lesions, in order to find new miR-based biomarkers for early detection of pancreatic cancer.

Pancreas, 2008

The circumstances that determine how acute pancreatitis (AP) becomes severe are unknown. Differen... more The circumstances that determine how acute pancreatitis (AP) becomes severe are unknown. Differences in cytokine genetic encoding may determine the severity or influence the etiology of AP. This article investigates the relationship between different polymorphisms of tumor necrosis factor alpha (TNF-alpha), interleukin 1 (IL-1), IL-1 receptor antagonist, IL-6, and IL-10 with the severity and etiology of AP and the serum levels of the cytokine encoded. Patients with AP were included prospectively. Severity of the disease was determined according to Atlanta classification. Serum levels of these cytokines were determined within the first 72 hours after the onset of symptoms. The following polymorphisms were determined by polymerase chain reaction: IL-1a -889, IL-1b +3954, IL-1b -511, variable number tandem repeats, IL-6 -174, IL-6 -597, IL-10 -592, TNF-alpha 308, TNF-alpha 238, and TNF-B250. Eighty-four patients were included. The GA genotype of the TNF-alpha 238 polymorphism was associated with more frequent respiratory failure and shock than the GG genotype. Gallstone pancreatitis was associated with the CC genotype of the IL-6 -174 CC polymorphism. AG genotype of the TNF-alpha 238 polymorphism is associated with organic failure in patients with AP. The CC genotype of the IL-6 174 polymorphism is associated with biliary etiology of acute pancreatitis.

Neuroscience, 2009

Excitability and axon/dendrite specification are the most distinctive features in the establishme... more Excitability and axon/dendrite specification are the most distinctive features in the establishment of neuronal polarization. Conditioned medium from rat sciatic nerve (CM) induced a neuronal-like morphology in PC12 cells. Here we show that CM neuritogenic activity is limited to the induction of dendrites in PC12 cells. However, treatment of these cells with CM in combination with a generic inhibitor for tyrosine kinase receptors (k252a) promoted the enhancement of neurite length, development of axons and induction of sodium currents. On the other hand, specific inhibition of TrkA and p75 NTR receptors in CM-treated cells reduced the neurite length in comparison with cells treated only with CM, although the effect over the induction of sodium currents was continuously observed. These results suggested that CM had some components that, even though are able to start the morphological cell differentiation and produce short neurites (likely acting through TrkA and p75 NTR ), can restrain further neurite extension. Depletion of pro-NGF isoforms from CM produced a similar effect as the exerted by k252a, TrkA and p75 NTR receptor inhibitors in CM-treated cells, inducing the elicitation of sodium currents. These results suggested that the effect of CM might be mediated through pro-NGF. The difference between the results obtained with the generic inhibitor for Trk receptors and the specific inhibitors for TrkA and p75 NTR receptors in CM-treated cells, suggested that alternative pathways could be used to regulate neurite elongation, axon specification and sodium currents in PC12 cells. These findings represent important clues to improve the understanding of the initiation of neuronal polarity. (M. Longart). Abbreviations: Ab, antibody; bFGF, basic fibroblast growth factor; CM, rat sciatic nerve conditioned media; FBS, fetal bovine serum; HS, horse serum; IP, immunoprecipitation; k252a, generic tyrosine kinase receptor inhibitor; NGF, nerve growth factor; NGS, normal goat serum; PC12 cells, cell line derived from a pheochromocytoma of the rat adrenal medulla; p75Inh, p75 neurotrophin receptor inhibitor; pro-NGF, precursor of NGF; p75 NTR , p75 neurotrophin receptor; Trk, tyrosine kinase neurotrophin receptor; TrkAI, tyrosine kinase receptor A inhibitor.

Leukemia and Lymphoma, 1995

The p53 gene located in the short arm of chromosome 17 at position 17p13, is involved in the nega... more The p53 gene located in the short arm of chromosome 17 at position 17p13, is involved in the negative regulation of cellular growth. p53 mutation seems to be the most frequent genetic alteration found in human cancer. Mutant conformation of the p53 gene is associated with cell proliferation and tumour progression, and in most cases implies p53 stabilization, which renders the p53 protein detectable through the use of immunohistochemical techniques. p53 expression is a frequent finding in high grade lymphomas of either B or T cell lineage, having been detected in 30% of cases in our series. The focal presence of p53+ cells was seen in a wide range of low and high grade lymphomas, including lymphadenitis and reactive tonsils. In 37.5% of cases this increased expression of p53 was secondary to mutation in highly conserved regions (exons 5-8). Unlike findings reported in other tumours, in lymphomas, p53 expression seems to be secondary to genetic alterations other than p53 mutation. Initial data suggest that the MDM2 protein could be involved in inactivating p53 protein in most of these cases. Finally, p53 expression has been found to be a poor prognostic marker in high grade B-cell lymphomas in a large series of cases. High p53 expression was associated with a short survival, this relation being stronger in cases with simultaneous bcl2 expression.

The Journal of Pathology, 1992

P53 is a tumour suppressor gene, located in the short arm of chromosome 17, which encodes for a n... more P53 is a tumour suppressor gene, located in the short arm of chromosome 17, which encodes for a nuclear protein involved in the control of cellular growth, regulating the entry of the cell into the S-phase. P53 mutations have been identified in a progressively increasing number of human malignancies. Nuclear p53 protein is usually present in non-tumour cells in minute concentrations, due to its short half-life. In contrast, tumours with p53 mRNA mutations show a higher nuclear protein concentration, detectable by immunohistological techniques, due to stabilization by complexing with other proteins such as heat-shock protein or wild-type p53 protein. Levels of nuclear p53 protein detected by immunohistochemistry with the monoclonal antibody PAb 1801 were measured with the aid of an image analysis system in 83 non-Hodgkin's lymphomas (NHLs) and 13 cases of Hodgkin's disease, as well as in 14 cases of normal thymus, reactive tonsils, and lymphadenitis. High levels of p53 protein (greater than 5 per cent of the cells) were present only in high-grade lymphomas (in the proportion 13/55), with a peak incidence in Burkitt's lymphoma (5/8 cases). Lower levels (less than 5 per cent) of p53 protein were detected in low-grade B- and T-cell lymphomas, as well as in most of the cases of Hodgkin's disease, where p53 protein was selectively present in Hodgkin and Reed-Sternberg cells. In 5/14 reactive tonsils or lymph nodes, occasional p53-positive cells were identified. These results suggest a relationship between levels of p53 protein and the aggressiveness of NHL.(ABSTRACT TRUNCATED AT 250 WORDS)

Gastrointestinal Endoscopy, 2009

Video capsule endoscopy (VCE) examination of the small bowel is not complete in approximately 20%... more Video capsule endoscopy (VCE) examination of the small bowel is not complete in approximately 20% of the procedures. This fact limits its diagnostic yield. One of the main factors that influences the small-bowel transit time (SBTT) is the gastric transit time (GTT), ie, the interval in which the capsule stays in the stomach. It has been described that placing the patient in a right lateral position (RLP) after swallowing the capsule could decrease the GTT. To investigate whether the RLP, after the patient swallows the capsule, shortens the GTT and, secondarily, increases the rate of complete procedures. Randomized prospective study. Third-level hospital. Consecutive outpatients in whom VCE was indicated. Exclusion criteria were inpatients and previous gastric surgery. GTT for RLP 30 minutes after swallowing the capsule versus non-RLP (standing up position). The GTT, SBTT, and rate of complete procedures (examination of the entire small bowel). We did not observe significant differences in the GTT, the SBTT, and the complete procedures between groups. Only outpatients were included. RLP after swallowing the capsule does not influence either GTT nor the rate of VCE complete procedures.

Endoscopy, 1984

A young person having no history of abdominal surgery who presents with a small bowel obstruction... more A young person having no history of abdominal surgery who presents with a small bowel obstruction is likely to have either a hernia or a neoplasm of the small intestine; associated rectal bleeding or bloody diarrhea adds the diagnostic possibilities of intussusception and intestinal ischemia. Diseases do not read textbooks or journals, however, and Meckel's diverticulum also may manifest with these symptoms. Small bowel obstruction caused by Meckel's diverticula may result from invagination of the diverticulum and intussusception with the diverticulum as the lead point, herniation of bowel through a defect in the diverticular mesentery, volvulus through or obstruction from a fibrous remnant of the omphalomesenteric duct, an entrapped foreign body such as an enterolith or a stricture from superimposed peptic disease, or even superimposed Crohn's disease. On physical examination think intussusception when there is an ''empty'' right lower quadrant and a distended upper abdomen, so-called Dance's sign. Clearly, it is easier to make the diagnosis of intussusception on CT scan than at colonoscopy, but neither will yield a specific cause for the obstruction and for that we need the help of our colleagues, the surgeon and the pathologist.

Dermatologic Surgery, 2004

BACKGROUND. The use of chemotherapy in organ transplant recipients (OTRs) with advanced and metas... more BACKGROUND. The use of chemotherapy in organ transplant recipients (OTRs) with advanced and metastatic cutaneous squamous cell carcinoma (SCC) remains relatively unexplored in dermatology. Advances in the use of chemotherapy in metastatic head and neck squamous cell carcinoma (HNSCC) may be applicable to this increasingly common disease. OBJECTIVE. The objective of this study was to determine whether recent advances in the role of chemotherapy in the management of HNSCC and cutaneous SCC offer insights into treatment strategies for metastatic cutaneous SCC. METHODS. We reviewed the literature pertaining to treatment of advanced and metastatic HNSCC and cutaneous SCC, with particular attention to the role of chemotherapy. In addition,

Clinical Gastroenterology and Hepatology, 2014

Clinical Gastroenterology and Hepatology, 2013

Predicting level of fluid sequestration could help identify patients with acute pancreatitis (AP)... more Predicting level of fluid sequestration could help identify patients with acute pancreatitis (AP) who need more or less aggressive fluid resuscitation. We investigated factors associated with level of fluid sequestration in the first 48 hours after hospital admission in patients with AP and effects on outcome. We analyzed data from consecutive adult patients with AP admitted to the Brigham and Women's Hospital in Boston, Massachusetts, from June 2005 to December 2007 (n = 266) or the Alicante University General Hospital in Spain from September 2010 to December 2012 (n = 137). Level of fluid sequestration in the first 48 hours after hospital admission was calculated by subtracting the total amount of fluid administered and lost in the first 48 hours of hospitalization. Demographic and clinical variables obtained in the emergency department were analyzed to identify factors associated with level of fluid sequestration in the first 48 hours after hospital admission. Outcome assessed included length of hospital stay, acute fluid collection(s), pancreatic necrosis, persistent organ failure, and mortality. The median level of fluid sequestration in the first 48 hours after hospital admission was 3.2 L (1.4-5 L). The simple and multiple linear regression models showed that younger age, alcohol etiology, hematocrit, glucose, and systemic inflammatory response syndrome were significantly associated with increased levels of fluid sequestration in the first 48 hours after hospital admission. Increased level of fluid sequestration in the first 48 hours was significantly associated with longer hospital stays and higher rates of acute fluid collection, pancreatic necrosis, and persistent organ failure. There was a nonsignificant trend toward a higher level of fluid sequestration in the first 48 hours among patients who died. Age, alcoholic etiology of AP, hematocrit, glucose, and presence of systemic inflammatory response syndrome in the emergency department were independent predictors of increased levels of fluid sequestration in the first 48 hours after hospital admission. These patients have higher risks of local and systemic complications and longer hospital stays.

Antimicrobial Agents and Chemotherapy, 2009

Leishmaniasis is parasitic disease that is an important problem of public health worldwide. Intra... more Leishmaniasis is parasitic disease that is an important problem of public health worldwide. Intramuscularly administered glucantime and pentostam are the most common drugs used for treatment of this disease, but they have significant limitations due to toxicity and increasing resistance. A recent breakthrough has been the introduction of orally administered miltefosine for the treatment of visceral, cutaneous, and mucocutaneous leishmaniasis, but the relative high cost and concerns about teratogenicity have limited the use of this drug. Searching for alternative drugs, we previously demonstrated that the antiarrhythmic drug amiodarone is active against Leishmania mexicana promastigotes and intracellular amastigotes, acting via disruption of intracellular Ca 2؉ homeostasis (specifically at the mitochondrion and the acidocalcisomes of these parasites) and through inhibition of the parasite's de novo sterol biosynthesis (X. ). In the present work, we found that miltefosine also disrupts the parasite's intracellular Ca 2؉ homeostasis, in this case by inducing a large increase in intracellular Ca 2؉ levels, probably through the activation of a plasma membrane Ca 2؉ channel. We also investigated the in vitro and in vivo activities of amiodarone and miltefosine, used alone or in combination, on L. mexicana. It was found that the drug combination had synergistic effects on the proliferation of intracellular amastigotes growing inside macrophages and led 90% of parasitological cures in a murine model of leishmaniasis, as revealed by a PCR assay using a novel DNA sequence specific for L. mexicana.

ABSTRACT Nestlings of many brood parasites are reared together with those of their hosts, but sti... more ABSTRACT Nestlings of many brood parasites are reared together with those of their hosts, but still manage to monopolize,a disproportionate share of the food delivered by adult hosts. Weh ypothesized that: (1) the low levels of host-speciWc pathogens of such brood parasite nestlings provide them with an advantage,in competition,for limited food; (2) a higher,provisioning rate and the re- sulting better

JOP : Journal of the pancreas, 2003

Pancreatic neoplasms are an uncommon aetiology of acute pancreatitis. Pancreatic neuroendocrine t... more Pancreatic neoplasms are an uncommon aetiology of acute pancreatitis. Pancreatic neuroendocrine tumours are a rare subgroup of pancreatic neoplasms. We report on three patients having acute pancreatitis secondary to pancreatic neuroendocrine tumours, one of them with severe pancreatitis, and review the published cases up to now. Only 22 patients with acute pancreatitis secondary to pancreatic neuroendocrine tumours have been reported (including the present cases). Most of these cases were of non-functioning neoplasms and the course of the pancreatitis tended to be mild. In the most recent reports and in the present cases, the initial diagnostic method was CT scan. Less than half had metastases when the tumour was diagnosed and mortality from these neoplasms reached approximately 50%. Pancreatic neuroendocrine tumours can cause acute pancreatitis even in patients under 50 years of age. On many occasions, the tumours are non-functioning; therefore, acute pancreatitis may be the first ...

JOP : Journal of the pancreas, 2006

Complete agenesis of the dorsal pancreas is an unusual congenital anomaly. Nowadays, the diagnosi... more Complete agenesis of the dorsal pancreas is an unusual congenital anomaly. Nowadays, the diagnosis is based on four imaging studies: transabdominal ultrasonography, computed tomography, magnetic resonance cholangiopancreatography and, the gold-standard, endoscopic retrograde cholangiopancreatography. Sometimes the ability of these studies are limited to distinguishing agenesis of the dorsal pancreas from other congenital abnormalities. Endoscopic ultrasound is a minimally invasive technique which permits us to obtain high resolution images of the pancreatic parenchyma and ductal system. We report the case of a 23-year-old woman with recurrent episodes of acute pancreatitis and non-conclusive classic imaging studies. Complete agenesis of the dorsal pancreas was demonstrated by endoscopic ultrasound. Endoscopic ultrasound may be useful in the diagnosis of agenesis of the dorsal pancreas.

Skeletal Radiology, 2011

Objective To determine the accuracy of guided computed tomography aspiration in the detection of ... more Objective To determine the accuracy of guided computed tomography aspiration in the detection of septic hip prosthesis before surgery. Materials and Methods Sixty-three patients (35 women and 28 men; age range, 29-86 years; mean age, 71 years) with clinically suspected septic hip prosthesis were prospectively studied with independent review board (IRB) approval. Volume and microbiological cultures of aspirated fluid and several computed tomography imaging findings such as periprosthetic fluid collections, prosthetic acetabular malposition, and heterotopic ossification were analyzed. All patients underwent revision surgery and infection was finally diagnosed in 33 patients. Results Statistical comparative analysis was performed comparing computed tomography aspiration and surgical findings (95% CI; level of significance at P=0.05 two-sided) with 70% sensitivity, 100% specificity, 84% accuracy, 100% positive predictive value, and 75% negative predictive value. Using Fisher's exact test, the presence of periprosthetic fluid collections (P=0.001), prosthetic acetabular malposition (P=0.025) and aspirated fluid volume (P=0.009) were significantly higher in infected than in non-infected prostheses, whereas heterotopic ossification was not (P=0.429). Conclusion Computed tomography aspiration is accurate to preoperatively diagnose septic hip prosthesis on the basis of volume and bacterial cultures of aspirated joint fluid. Furthermore, imaging findings such as periprosthetic fluid collections and prosthetic acetabular malposition strongly suggest infected prosthesis.

Pancreatology, 2013

Aims: Pancreatic cancer is the 4th cancer-related death cause in western countries. Early detecti... more Aims: Pancreatic cancer is the 4th cancer-related death cause in western countries. Early detection methods are needed in order to improve its prognosis. Many expectations in this sense have arisen since the discovery of microRNAs (miR). We aimed to analyze the miRNome of PDAC and IPMN lesions, in order to find new miR-based biomarkers for early detection of pancreatic cancer.

Pancreas, 2008

The circumstances that determine how acute pancreatitis (AP) becomes severe are unknown. Differen... more The circumstances that determine how acute pancreatitis (AP) becomes severe are unknown. Differences in cytokine genetic encoding may determine the severity or influence the etiology of AP. This article investigates the relationship between different polymorphisms of tumor necrosis factor alpha (TNF-alpha), interleukin 1 (IL-1), IL-1 receptor antagonist, IL-6, and IL-10 with the severity and etiology of AP and the serum levels of the cytokine encoded. Patients with AP were included prospectively. Severity of the disease was determined according to Atlanta classification. Serum levels of these cytokines were determined within the first 72 hours after the onset of symptoms. The following polymorphisms were determined by polymerase chain reaction: IL-1a -889, IL-1b +3954, IL-1b -511, variable number tandem repeats, IL-6 -174, IL-6 -597, IL-10 -592, TNF-alpha 308, TNF-alpha 238, and TNF-B250. Eighty-four patients were included. The GA genotype of the TNF-alpha 238 polymorphism was associated with more frequent respiratory failure and shock than the GG genotype. Gallstone pancreatitis was associated with the CC genotype of the IL-6 -174 CC polymorphism. AG genotype of the TNF-alpha 238 polymorphism is associated with organic failure in patients with AP. The CC genotype of the IL-6 174 polymorphism is associated with biliary etiology of acute pancreatitis.

Neuroscience, 2009

Excitability and axon/dendrite specification are the most distinctive features in the establishme... more Excitability and axon/dendrite specification are the most distinctive features in the establishment of neuronal polarization. Conditioned medium from rat sciatic nerve (CM) induced a neuronal-like morphology in PC12 cells. Here we show that CM neuritogenic activity is limited to the induction of dendrites in PC12 cells. However, treatment of these cells with CM in combination with a generic inhibitor for tyrosine kinase receptors (k252a) promoted the enhancement of neurite length, development of axons and induction of sodium currents. On the other hand, specific inhibition of TrkA and p75 NTR receptors in CM-treated cells reduced the neurite length in comparison with cells treated only with CM, although the effect over the induction of sodium currents was continuously observed. These results suggested that CM had some components that, even though are able to start the morphological cell differentiation and produce short neurites (likely acting through TrkA and p75 NTR ), can restrain further neurite extension. Depletion of pro-NGF isoforms from CM produced a similar effect as the exerted by k252a, TrkA and p75 NTR receptor inhibitors in CM-treated cells, inducing the elicitation of sodium currents. These results suggested that the effect of CM might be mediated through pro-NGF. The difference between the results obtained with the generic inhibitor for Trk receptors and the specific inhibitors for TrkA and p75 NTR receptors in CM-treated cells, suggested that alternative pathways could be used to regulate neurite elongation, axon specification and sodium currents in PC12 cells. These findings represent important clues to improve the understanding of the initiation of neuronal polarity. (M. Longart). Abbreviations: Ab, antibody; bFGF, basic fibroblast growth factor; CM, rat sciatic nerve conditioned media; FBS, fetal bovine serum; HS, horse serum; IP, immunoprecipitation; k252a, generic tyrosine kinase receptor inhibitor; NGF, nerve growth factor; NGS, normal goat serum; PC12 cells, cell line derived from a pheochromocytoma of the rat adrenal medulla; p75Inh, p75 neurotrophin receptor inhibitor; pro-NGF, precursor of NGF; p75 NTR , p75 neurotrophin receptor; Trk, tyrosine kinase neurotrophin receptor; TrkAI, tyrosine kinase receptor A inhibitor.

Leukemia and Lymphoma, 1995

The p53 gene located in the short arm of chromosome 17 at position 17p13, is involved in the nega... more The p53 gene located in the short arm of chromosome 17 at position 17p13, is involved in the negative regulation of cellular growth. p53 mutation seems to be the most frequent genetic alteration found in human cancer. Mutant conformation of the p53 gene is associated with cell proliferation and tumour progression, and in most cases implies p53 stabilization, which renders the p53 protein detectable through the use of immunohistochemical techniques. p53 expression is a frequent finding in high grade lymphomas of either B or T cell lineage, having been detected in 30% of cases in our series. The focal presence of p53+ cells was seen in a wide range of low and high grade lymphomas, including lymphadenitis and reactive tonsils. In 37.5% of cases this increased expression of p53 was secondary to mutation in highly conserved regions (exons 5-8). Unlike findings reported in other tumours, in lymphomas, p53 expression seems to be secondary to genetic alterations other than p53 mutation. Initial data suggest that the MDM2 protein could be involved in inactivating p53 protein in most of these cases. Finally, p53 expression has been found to be a poor prognostic marker in high grade B-cell lymphomas in a large series of cases. High p53 expression was associated with a short survival, this relation being stronger in cases with simultaneous bcl2 expression.

The Journal of Pathology, 1992

P53 is a tumour suppressor gene, located in the short arm of chromosome 17, which encodes for a n... more P53 is a tumour suppressor gene, located in the short arm of chromosome 17, which encodes for a nuclear protein involved in the control of cellular growth, regulating the entry of the cell into the S-phase. P53 mutations have been identified in a progressively increasing number of human malignancies. Nuclear p53 protein is usually present in non-tumour cells in minute concentrations, due to its short half-life. In contrast, tumours with p53 mRNA mutations show a higher nuclear protein concentration, detectable by immunohistological techniques, due to stabilization by complexing with other proteins such as heat-shock protein or wild-type p53 protein. Levels of nuclear p53 protein detected by immunohistochemistry with the monoclonal antibody PAb 1801 were measured with the aid of an image analysis system in 83 non-Hodgkin's lymphomas (NHLs) and 13 cases of Hodgkin's disease, as well as in 14 cases of normal thymus, reactive tonsils, and lymphadenitis. High levels of p53 protein (greater than 5 per cent of the cells) were present only in high-grade lymphomas (in the proportion 13/55), with a peak incidence in Burkitt's lymphoma (5/8 cases). Lower levels (less than 5 per cent) of p53 protein were detected in low-grade B- and T-cell lymphomas, as well as in most of the cases of Hodgkin's disease, where p53 protein was selectively present in Hodgkin and Reed-Sternberg cells. In 5/14 reactive tonsils or lymph nodes, occasional p53-positive cells were identified. These results suggest a relationship between levels of p53 protein and the aggressiveness of NHL.(ABSTRACT TRUNCATED AT 250 WORDS)

Gastrointestinal Endoscopy, 2009

Video capsule endoscopy (VCE) examination of the small bowel is not complete in approximately 20%... more Video capsule endoscopy (VCE) examination of the small bowel is not complete in approximately 20% of the procedures. This fact limits its diagnostic yield. One of the main factors that influences the small-bowel transit time (SBTT) is the gastric transit time (GTT), ie, the interval in which the capsule stays in the stomach. It has been described that placing the patient in a right lateral position (RLP) after swallowing the capsule could decrease the GTT. To investigate whether the RLP, after the patient swallows the capsule, shortens the GTT and, secondarily, increases the rate of complete procedures. Randomized prospective study. Third-level hospital. Consecutive outpatients in whom VCE was indicated. Exclusion criteria were inpatients and previous gastric surgery. GTT for RLP 30 minutes after swallowing the capsule versus non-RLP (standing up position). The GTT, SBTT, and rate of complete procedures (examination of the entire small bowel). We did not observe significant differences in the GTT, the SBTT, and the complete procedures between groups. Only outpatients were included. RLP after swallowing the capsule does not influence either GTT nor the rate of VCE complete procedures.

Endoscopy, 1984

A young person having no history of abdominal surgery who presents with a small bowel obstruction... more A young person having no history of abdominal surgery who presents with a small bowel obstruction is likely to have either a hernia or a neoplasm of the small intestine; associated rectal bleeding or bloody diarrhea adds the diagnostic possibilities of intussusception and intestinal ischemia. Diseases do not read textbooks or journals, however, and Meckel's diverticulum also may manifest with these symptoms. Small bowel obstruction caused by Meckel's diverticula may result from invagination of the diverticulum and intussusception with the diverticulum as the lead point, herniation of bowel through a defect in the diverticular mesentery, volvulus through or obstruction from a fibrous remnant of the omphalomesenteric duct, an entrapped foreign body such as an enterolith or a stricture from superimposed peptic disease, or even superimposed Crohn's disease. On physical examination think intussusception when there is an ''empty'' right lower quadrant and a distended upper abdomen, so-called Dance's sign. Clearly, it is easier to make the diagnosis of intussusception on CT scan than at colonoscopy, but neither will yield a specific cause for the obstruction and for that we need the help of our colleagues, the surgeon and the pathologist.

Dermatologic Surgery, 2004

BACKGROUND. The use of chemotherapy in organ transplant recipients (OTRs) with advanced and metas... more BACKGROUND. The use of chemotherapy in organ transplant recipients (OTRs) with advanced and metastatic cutaneous squamous cell carcinoma (SCC) remains relatively unexplored in dermatology. Advances in the use of chemotherapy in metastatic head and neck squamous cell carcinoma (HNSCC) may be applicable to this increasingly common disease. OBJECTIVE. The objective of this study was to determine whether recent advances in the role of chemotherapy in the management of HNSCC and cutaneous SCC offer insights into treatment strategies for metastatic cutaneous SCC. METHODS. We reviewed the literature pertaining to treatment of advanced and metastatic HNSCC and cutaneous SCC, with particular attention to the role of chemotherapy. In addition,

Clinical Gastroenterology and Hepatology, 2014

Clinical Gastroenterology and Hepatology, 2013

Predicting level of fluid sequestration could help identify patients with acute pancreatitis (AP)... more Predicting level of fluid sequestration could help identify patients with acute pancreatitis (AP) who need more or less aggressive fluid resuscitation. We investigated factors associated with level of fluid sequestration in the first 48 hours after hospital admission in patients with AP and effects on outcome. We analyzed data from consecutive adult patients with AP admitted to the Brigham and Women's Hospital in Boston, Massachusetts, from June 2005 to December 2007 (n = 266) or the Alicante University General Hospital in Spain from September 2010 to December 2012 (n = 137). Level of fluid sequestration in the first 48 hours after hospital admission was calculated by subtracting the total amount of fluid administered and lost in the first 48 hours of hospitalization. Demographic and clinical variables obtained in the emergency department were analyzed to identify factors associated with level of fluid sequestration in the first 48 hours after hospital admission. Outcome assessed included length of hospital stay, acute fluid collection(s), pancreatic necrosis, persistent organ failure, and mortality. The median level of fluid sequestration in the first 48 hours after hospital admission was 3.2 L (1.4-5 L). The simple and multiple linear regression models showed that younger age, alcohol etiology, hematocrit, glucose, and systemic inflammatory response syndrome were significantly associated with increased levels of fluid sequestration in the first 48 hours after hospital admission. Increased level of fluid sequestration in the first 48 hours was significantly associated with longer hospital stays and higher rates of acute fluid collection, pancreatic necrosis, and persistent organ failure. There was a nonsignificant trend toward a higher level of fluid sequestration in the first 48 hours among patients who died. Age, alcoholic etiology of AP, hematocrit, glucose, and presence of systemic inflammatory response syndrome in the emergency department were independent predictors of increased levels of fluid sequestration in the first 48 hours after hospital admission. These patients have higher risks of local and systemic complications and longer hospital stays.

Antimicrobial Agents and Chemotherapy, 2009

Leishmaniasis is parasitic disease that is an important problem of public health worldwide. Intra... more Leishmaniasis is parasitic disease that is an important problem of public health worldwide. Intramuscularly administered glucantime and pentostam are the most common drugs used for treatment of this disease, but they have significant limitations due to toxicity and increasing resistance. A recent breakthrough has been the introduction of orally administered miltefosine for the treatment of visceral, cutaneous, and mucocutaneous leishmaniasis, but the relative high cost and concerns about teratogenicity have limited the use of this drug. Searching for alternative drugs, we previously demonstrated that the antiarrhythmic drug amiodarone is active against Leishmania mexicana promastigotes and intracellular amastigotes, acting via disruption of intracellular Ca 2؉ homeostasis (specifically at the mitochondrion and the acidocalcisomes of these parasites) and through inhibition of the parasite's de novo sterol biosynthesis (X. ). In the present work, we found that miltefosine also disrupts the parasite's intracellular Ca 2؉ homeostasis, in this case by inducing a large increase in intracellular Ca 2؉ levels, probably through the activation of a plasma membrane Ca 2؉ channel. We also investigated the in vitro and in vivo activities of amiodarone and miltefosine, used alone or in combination, on L. mexicana. It was found that the drug combination had synergistic effects on the proliferation of intracellular amastigotes growing inside macrophages and led 90% of parasitological cures in a murine model of leishmaniasis, as revealed by a PCR assay using a novel DNA sequence specific for L. mexicana.

ABSTRACT Nestlings of many brood parasites are reared together with those of their hosts, but sti... more ABSTRACT Nestlings of many brood parasites are reared together with those of their hosts, but still manage to monopolize,a disproportionate share of the food delivered by adult hosts. Weh ypothesized that: (1) the low levels of host-speciWc pathogens of such brood parasite nestlings provide them with an advantage,in competition,for limited food; (2) a higher,provisioning rate and the re- sulting better