The bacterium Listeria monocytogenesis widely distributed in nature, and survives for up to twelv... more The bacterium Listeria monocytogenesis widely distributed in nature, and survives for up to twelve years in association with plants (Farber & Peterkin 199n It has beeii detected on lettuce, cabbage, potatoes, radishes and cucumbers (Rocourt 1989) as well as on pre cut, packaged salad vegetables (Petran et al. 1988, Beuchat & Brackett 1991). It causes opportunistic infections, especialIy in immunosuppresed patients. Several Lfsteria outbreaks have been associated, with consumption oí vegetables, and infection has 20-30% lethality (Rocourt 1989). Few reports about its presence in food were available before 1986, but was later found also in foods such as dairy products and Uieats. In Costa Rica, a 20% prevalence was found in fresh salads (Monge y Arias 1995). This work determines the ,survival of L monocytogenes in fresh chopped cabbage treated With lemon juice or chlorine in several concentratións and times, simulating the preparation conditions and consumption'times of Costa Ric...
Introduccion. En los ultimos anos, se ha dado un incremento en el hecho de consumir vegetales fre... more Introduccion. En los ultimos anos, se ha dado un incremento en el hecho de consumir vegetales frescos como parte de una dieta sana, pero no se puede descartar el que estos pueden actuar como vehiculos de microorganismos patogenos, como Listeria monocytogenes. Material y metodos. Se evaluo la presencia de Listeria monocytogenes en 50 muestras de ensalada, segun la metodologia descrita por Vanderzant y Splittstoesser. Resultados. Se aislo Listeria spp. a partir de 32% (16/50) de las muestras analizadas, de estas, 8% (10/16) correspondio a L. monocytogenes, 8% (4/16) a L. welshimeri y 4% (2/16) a L. murrai. Discusion. La presencia de L. monocytogenes en ensalada de vegetales frescos representa un riesgo potencial para la salud publica, dado que su dosis infectante no ha sido claramente definida y esta demostrada su capacidad de sobrevivir en vegetales crudos. Se debe de promover cambios de dieta en grupos donde esta bacteria representa un riesgo.
technique, 36% of the strains showed resistance to amoxycillin-clavulanic acid, 25,3% to cefaclor... more technique, 36% of the strains showed resistance to amoxycillin-clavulanic acid, 25,3% to cefaclor and 14,7% to cefuroxime. All strains were sensible to imipenem and ciprofloxacin. Using the ATB antibiogram methodology, bacteria showed resistance to amoxycillin (74,6%), amoxycillinclavulanic acid (34,6%), ticarcillin-cefalotine (22,6%) and piperacillin (2,6%). All strains were sensible to the other ten antibiotics evaluated. Conclusions. It is urgent to assure strict hygiene during the preparation and handling of enteral feeding solutions used at hospitals, so that they do not become a potential source of resistant bacteria that can limit the recovery of patients.
In Costa Rica, a total of 640 samples from eight different vegetables used for raw consumption we... more In Costa Rica, a total of 640 samples from eight different vegetables used for raw consumption were analyzed for the presence of Cryptosporidium spp. oocysts, fecal coliforms, and Escherichia coli. Cryptosporidium spp. oocysts were found in 5.0% (4 samples) of cilantro leaves, 8.7% (7 samples) of cilantro roots and 2.5% (2 samples) of lettuce samples. A 1.2% contamination rate was detected in samples of other vegetables (radish, tomato, cucumbers and carrot). Oocysts of this parasite were absent from cabbage. A greater percentage of positive samples was found during the rainy season, and only in cilantro roots and lettuce was a positive linear correlation (P < 0.05) established between the presence of Cryptosporidium spp. oocysts and fecal coliforms and E. coli.
Archivos Latinoamericanos De Nutricion, Jun 1, 2000
The nutritional and microbiological quality of 80 soybean sausage samples (50% frankfurter and 50... more The nutritional and microbiological quality of 80 soybean sausage samples (50% frankfurter and 50% sausage mortadela) was studied. On average, the protein content was 17.5 g/100 g in sausage mortadela and 20 g/100 g in frankfurter. The mean total fat content was 5.5 g/100 g for both products. However when products of different manufacture industries were compared, a highly significant difference (p = 0.0000) in the fatty acids speciation between both groups and between samples of the same product were found. Bigger differences were found in the content of palmitic acid (C16:0), oleic acid (C18:1) and linoleic acid (C18:2). Cholesterol was not detected in samples analyzed. On average the atherogenicity index was 0.55 for sausage mortadela and 0.59 for frankfurter. A consumption of 25 grams of of soybean protein from these sausages can bring an intake of saturated fatty acids between 20-90% of the daily recommendation. Likewise, they can supply between 12-70% of the recommended daily polyunsaturated fatty acids. These variations are owing to the big difference in fatty acids speciation in each sausage brand. Around 20% of soybean sausages studied showed total coliform levels above 10(4)/g, being more frequent in sausage mortadela. Also 60% of this product and 10% of frankfurters showed psychrotroph levels of 10(6)/g. Clostridium perfringens, in levels above 10(2)/g was evidenciated in 5% of samples, Escherichia coli was not isolated from them. The findings of this study suggest the urgent need for implementing a quality control system for soybean sausages, before national health authorities consider to support nutritional campainings that promote their consumption.
An adverse lipid profile is a major risk factor for atherosclerosis. This study evaluated the lip... more An adverse lipid profile is a major risk factor for atherosclerosis. This study evaluated the lipid profiles of 683 schoolchildren aged 10 to 13 years. The prevalence of both high LDL and high total cholesterol levels was significantly (p < .001) higher in private schoolchildren than in public schoolchildren. There were no significant differences in the prevalence of high triglyceride levels among the schoolchildren. Mean total cholesterol and LDL cholesterol levels were significantly higher in children whose parents had completed over 11 years of schooling. Private schoolchildren were more sedentary and tended to have a more atherogenic diet. Our data suggest that prevention programmes in primary schools are required to decrease the prevalence of cardiovascular risk factors, including abnormal lipid profiles.
... We also thank Dra. Eugenia Quintana for her help with transferrin satura-tion measurements an... more ... We also thank Dra. Eugenia Quintana for her help with transferrin satura-tion measurements and Jorge Astua for his help with blood sample collections. Page 51. ... 14. Dennis B, Ernst N, Hjortland M, Tillotson J, Grambasch V. The NHLBI nutrition data system. ...
The term "pediatric metabolic syndrome" includes a cluster of cardiovascular risk facto... more The term "pediatric metabolic syndrome" includes a cluster of cardiovascular risk factors such as insulin resistance, dyslipidemia (including increased triglycerides and decreased HDL cholesterol), hypertension, and obesity in children. No studies have been performed on this syndrome in a pediatric population in Costa Rica. To establish the prevalence of metabolic syndrome and its components in 8- to 10-year-old prepuberal overweight and obese schoolchildren. This cross-sectional survey was conducted in 214 overweight and obese boys and girls, aged 8 to 10 years, who were selected from six urban schools from San José, Costa Rica. Anthropometric measurements and determinations of blood glucose, insulin, triglycerides, total cholesterol, HDL cholesterol, and high-sensitivity C-reactive protein (hs-CRP) were performed. The homeostasis model assessment of insulin resistance (HOMA-IR) index and the Castelli index were calculated to assess insulin resistance and cardiovascular r...
In Costa Rica, a total of 640 samples from eight different vegetables used for raw consumption, w... more In Costa Rica, a total of 640 samples from eight different vegetables used for raw consumption, were analyzed for the presence of intestinal parasites and fecal coliforms. Eighty samples of each vegetable were analyzed, forty during the dry season and forty in the rainy. A greater, but unsignificant (p > 0.05) level of fecal coliforms was found during the dry season. Levels of Escherichia coli, were higher (p < 0.05) during the dry season in lettuce (Latuca sativa) and cilantro (Coleandrum sativum) leaves. Cysts of Endolimax nana, Entamoeba coli, Entamoeba histolytica, Giardia intestinalis and Cryptosporidium sp. were found in all vegetables. The greater percentage of positive samples was found during the dry season, although these relation was only corroborated (p < 0.05) in radish (Raphanus sativus) and cilantro leaves. Only lettuce and cilantro levels showed a positive linear correlation (p < 0.05) between occurrences of intestinal parasites and fecal coliforms.
Resumen: De julio 1993 a febrero 1994 se estudió la presencia de Listeria spp. en 220 muestras de... more Resumen: De julio 1993 a febrero 1994 se estudió la presencia de Listeria spp. en 220 muestras de leche cruda recolectadas directamente en tanques de almacenamiento de lecherías seleccionadas aleatoriamente en el área metro politana, San José, Costa Rica. Las muestras fueron analizadas con la metodología recomendada por la Intemational Dairy Federation. Se aisló Listeria spp. de 14 (6.4%) de las muestras, el 4.5% de las cepas fue L. innocua, el 1.4% L. welshimeri y el 0.5% L. gravi. No se aisló L. monocytogenes. Tampoco se determinaron variaciones estacionales en la presencia de esta bacteria.
Enteral feeding is the most common and preferred modality for providing nutritional support to ho... more Enteral feeding is the most common and preferred modality for providing nutritional support to hospital patients with a functional gastrointestinal tract that can not satisfy their nutritional requirements. Nevertheless, enteral feeding may be an important cause of bacterial infection. The aim of this study was to evaluate the microbial contamination level of enteral feedings distributed in Costa Rican hospitals. A total of 124 samples of enteral feeding, coming from five different hospitals from San José, Costa Rica, were evaluated during the second semester of 1997 and first of 1998 for the presence and identification of total and fecal coliforms, Pseudomonas sp. and Listeria sp. A subpopulation of the Pseudomonas isolated was analyzed for their antibiotic susceptibility patterns. The concentration of Gram negative rods in the samples of enteral feeding solutions ranged from 10(3) to 10(7) CFU/mL, markedly exceeding the permissible level (10(2) CFU/mL or less). The coliforms most ...
International Journal of Infectious Diseases, 2012
Background: Urinary tract infections (UTIs) are the most important cause of morbidity and mortali... more Background: Urinary tract infections (UTIs) are the most important cause of morbidity and mortality in the world affecting all age groups. It is estimated that 150 million cases of UTI occur on a global basis per year. Resistance to antibiotics is highly prevalent and growing as the global problem in management of UTI. Knowledge of pattern of antimicrobial agents among local isolates plays a major role for selecting appropriate and effective therapy. Objectives: The present study was conducted to determine in vitro susceptibility among Gram negative organisms obtained from urineagainst commonly used antimicrobials. Methods: Urine specimens submitted to the Department of Microbiology, BP Koirala Institute of Health Sciences (BPKIHS) Hospital for culture and sensitivity over one year period were evaluated. Isolation, identification and determination of antimicrobial susceptibility were done by standard microbiological techniques. Results: Out of 13011 urine specimens submitted, 2131(16.3%) comprises Gram negative uropathogens, among which the most prevalent was Escherichia coli (66.3%) followed by Klebsilla pneumoniae (11.7%), Acinetobacter anitratus (6.8%), Enterobacter aerogens (3.3%) and Pseudomonas aeruginosa (2.5%), Morganella morganii (1.3%), Proteus mirabilis (1.2%), Citrobacter frundii (0.7%), Klebsiella oxytoca (0.7%), Proteus vulgaris (0.56%). The majority (65.3%) were from female while (34.7%) were male patients. Most of the GNB isolates were found to be resistant to ampicillin (90%), norfloxacillin (60%) and ofloxacin (57.17%) where as they were susceptible to cotrimoxazole (73.2%), nitrofurantoin (69%) and amikacin (68.4%). Conclusion: Gram negative organisms remain the major cause of UTI. Various degree of antimicrobial resistance was observed among the uropathogens prevalent in our hospital. Regular monitoring of the resistance in the local isolates against the routinely used antimicrobial may have significant impact for the effective management of UTI.
and high (December-January) incidence of diarrhea associated with rotavirus, respectively. Lettuc... more and high (December-January) incidence of diarrhea associated with rotavirus, respectively. Lettuce samples were pooled and evaluated for rotavirus by enzyme-linked immunosorbent assay (ELISA) and for Hepatitis A virus by radioimmunoassay, polymerase chain reaction (PCR) and electron microscope. Three sample pools, collected during the period of high prevalence of diarrhea, were positive for rotavirus by ELISA and in one of them rotavirions were visualized by electron microscopy. Two samples pools collected during the same period were positive for Hepatitis A virus as shown by PCR. In almost all the pools fecal coliform bacteria were detected by cultivation and bacteriophages were visualized by electron microscopy.
The bacterium Listeria monocytogenesis widely distributed in nature, and survives for up to twelv... more The bacterium Listeria monocytogenesis widely distributed in nature, and survives for up to twelve years in association with plants (Farber & Peterkin 199n It has beeii detected on lettuce, cabbage, potatoes, radishes and cucumbers (Rocourt 1989) as well as on pre cut, packaged salad vegetables (Petran et al. 1988, Beuchat & Brackett 1991). It causes opportunistic infections, especialIy in immunosuppresed patients. Several Lfsteria outbreaks have been associated, with consumption oí vegetables, and infection has 20-30% lethality (Rocourt 1989). Few reports about its presence in food were available before 1986, but was later found also in foods such as dairy products and Uieats. In Costa Rica, a 20% prevalence was found in fresh salads (Monge y Arias 1995). This work determines the ,survival of L monocytogenes in fresh chopped cabbage treated With lemon juice or chlorine in several concentratións and times, simulating the preparation conditions and consumption'times of Costa Ric...
Introduccion. En los ultimos anos, se ha dado un incremento en el hecho de consumir vegetales fre... more Introduccion. En los ultimos anos, se ha dado un incremento en el hecho de consumir vegetales frescos como parte de una dieta sana, pero no se puede descartar el que estos pueden actuar como vehiculos de microorganismos patogenos, como Listeria monocytogenes. Material y metodos. Se evaluo la presencia de Listeria monocytogenes en 50 muestras de ensalada, segun la metodologia descrita por Vanderzant y Splittstoesser. Resultados. Se aislo Listeria spp. a partir de 32% (16/50) de las muestras analizadas, de estas, 8% (10/16) correspondio a L. monocytogenes, 8% (4/16) a L. welshimeri y 4% (2/16) a L. murrai. Discusion. La presencia de L. monocytogenes en ensalada de vegetales frescos representa un riesgo potencial para la salud publica, dado que su dosis infectante no ha sido claramente definida y esta demostrada su capacidad de sobrevivir en vegetales crudos. Se debe de promover cambios de dieta en grupos donde esta bacteria representa un riesgo.
technique, 36% of the strains showed resistance to amoxycillin-clavulanic acid, 25,3% to cefaclor... more technique, 36% of the strains showed resistance to amoxycillin-clavulanic acid, 25,3% to cefaclor and 14,7% to cefuroxime. All strains were sensible to imipenem and ciprofloxacin. Using the ATB antibiogram methodology, bacteria showed resistance to amoxycillin (74,6%), amoxycillinclavulanic acid (34,6%), ticarcillin-cefalotine (22,6%) and piperacillin (2,6%). All strains were sensible to the other ten antibiotics evaluated. Conclusions. It is urgent to assure strict hygiene during the preparation and handling of enteral feeding solutions used at hospitals, so that they do not become a potential source of resistant bacteria that can limit the recovery of patients.
In Costa Rica, a total of 640 samples from eight different vegetables used for raw consumption we... more In Costa Rica, a total of 640 samples from eight different vegetables used for raw consumption were analyzed for the presence of Cryptosporidium spp. oocysts, fecal coliforms, and Escherichia coli. Cryptosporidium spp. oocysts were found in 5.0% (4 samples) of cilantro leaves, 8.7% (7 samples) of cilantro roots and 2.5% (2 samples) of lettuce samples. A 1.2% contamination rate was detected in samples of other vegetables (radish, tomato, cucumbers and carrot). Oocysts of this parasite were absent from cabbage. A greater percentage of positive samples was found during the rainy season, and only in cilantro roots and lettuce was a positive linear correlation (P < 0.05) established between the presence of Cryptosporidium spp. oocysts and fecal coliforms and E. coli.
Archivos Latinoamericanos De Nutricion, Jun 1, 2000
The nutritional and microbiological quality of 80 soybean sausage samples (50% frankfurter and 50... more The nutritional and microbiological quality of 80 soybean sausage samples (50% frankfurter and 50% sausage mortadela) was studied. On average, the protein content was 17.5 g/100 g in sausage mortadela and 20 g/100 g in frankfurter. The mean total fat content was 5.5 g/100 g for both products. However when products of different manufacture industries were compared, a highly significant difference (p = 0.0000) in the fatty acids speciation between both groups and between samples of the same product were found. Bigger differences were found in the content of palmitic acid (C16:0), oleic acid (C18:1) and linoleic acid (C18:2). Cholesterol was not detected in samples analyzed. On average the atherogenicity index was 0.55 for sausage mortadela and 0.59 for frankfurter. A consumption of 25 grams of of soybean protein from these sausages can bring an intake of saturated fatty acids between 20-90% of the daily recommendation. Likewise, they can supply between 12-70% of the recommended daily polyunsaturated fatty acids. These variations are owing to the big difference in fatty acids speciation in each sausage brand. Around 20% of soybean sausages studied showed total coliform levels above 10(4)/g, being more frequent in sausage mortadela. Also 60% of this product and 10% of frankfurters showed psychrotroph levels of 10(6)/g. Clostridium perfringens, in levels above 10(2)/g was evidenciated in 5% of samples, Escherichia coli was not isolated from them. The findings of this study suggest the urgent need for implementing a quality control system for soybean sausages, before national health authorities consider to support nutritional campainings that promote their consumption.
An adverse lipid profile is a major risk factor for atherosclerosis. This study evaluated the lip... more An adverse lipid profile is a major risk factor for atherosclerosis. This study evaluated the lipid profiles of 683 schoolchildren aged 10 to 13 years. The prevalence of both high LDL and high total cholesterol levels was significantly (p < .001) higher in private schoolchildren than in public schoolchildren. There were no significant differences in the prevalence of high triglyceride levels among the schoolchildren. Mean total cholesterol and LDL cholesterol levels were significantly higher in children whose parents had completed over 11 years of schooling. Private schoolchildren were more sedentary and tended to have a more atherogenic diet. Our data suggest that prevention programmes in primary schools are required to decrease the prevalence of cardiovascular risk factors, including abnormal lipid profiles.
... We also thank Dra. Eugenia Quintana for her help with transferrin satura-tion measurements an... more ... We also thank Dra. Eugenia Quintana for her help with transferrin satura-tion measurements and Jorge Astua for his help with blood sample collections. Page 51. ... 14. Dennis B, Ernst N, Hjortland M, Tillotson J, Grambasch V. The NHLBI nutrition data system. ...
The term "pediatric metabolic syndrome" includes a cluster of cardiovascular risk facto... more The term "pediatric metabolic syndrome" includes a cluster of cardiovascular risk factors such as insulin resistance, dyslipidemia (including increased triglycerides and decreased HDL cholesterol), hypertension, and obesity in children. No studies have been performed on this syndrome in a pediatric population in Costa Rica. To establish the prevalence of metabolic syndrome and its components in 8- to 10-year-old prepuberal overweight and obese schoolchildren. This cross-sectional survey was conducted in 214 overweight and obese boys and girls, aged 8 to 10 years, who were selected from six urban schools from San José, Costa Rica. Anthropometric measurements and determinations of blood glucose, insulin, triglycerides, total cholesterol, HDL cholesterol, and high-sensitivity C-reactive protein (hs-CRP) were performed. The homeostasis model assessment of insulin resistance (HOMA-IR) index and the Castelli index were calculated to assess insulin resistance and cardiovascular r...
In Costa Rica, a total of 640 samples from eight different vegetables used for raw consumption, w... more In Costa Rica, a total of 640 samples from eight different vegetables used for raw consumption, were analyzed for the presence of intestinal parasites and fecal coliforms. Eighty samples of each vegetable were analyzed, forty during the dry season and forty in the rainy. A greater, but unsignificant (p > 0.05) level of fecal coliforms was found during the dry season. Levels of Escherichia coli, were higher (p < 0.05) during the dry season in lettuce (Latuca sativa) and cilantro (Coleandrum sativum) leaves. Cysts of Endolimax nana, Entamoeba coli, Entamoeba histolytica, Giardia intestinalis and Cryptosporidium sp. were found in all vegetables. The greater percentage of positive samples was found during the dry season, although these relation was only corroborated (p < 0.05) in radish (Raphanus sativus) and cilantro leaves. Only lettuce and cilantro levels showed a positive linear correlation (p < 0.05) between occurrences of intestinal parasites and fecal coliforms.
Resumen: De julio 1993 a febrero 1994 se estudió la presencia de Listeria spp. en 220 muestras de... more Resumen: De julio 1993 a febrero 1994 se estudió la presencia de Listeria spp. en 220 muestras de leche cruda recolectadas directamente en tanques de almacenamiento de lecherías seleccionadas aleatoriamente en el área metro politana, San José, Costa Rica. Las muestras fueron analizadas con la metodología recomendada por la Intemational Dairy Federation. Se aisló Listeria spp. de 14 (6.4%) de las muestras, el 4.5% de las cepas fue L. innocua, el 1.4% L. welshimeri y el 0.5% L. gravi. No se aisló L. monocytogenes. Tampoco se determinaron variaciones estacionales en la presencia de esta bacteria.
Enteral feeding is the most common and preferred modality for providing nutritional support to ho... more Enteral feeding is the most common and preferred modality for providing nutritional support to hospital patients with a functional gastrointestinal tract that can not satisfy their nutritional requirements. Nevertheless, enteral feeding may be an important cause of bacterial infection. The aim of this study was to evaluate the microbial contamination level of enteral feedings distributed in Costa Rican hospitals. A total of 124 samples of enteral feeding, coming from five different hospitals from San José, Costa Rica, were evaluated during the second semester of 1997 and first of 1998 for the presence and identification of total and fecal coliforms, Pseudomonas sp. and Listeria sp. A subpopulation of the Pseudomonas isolated was analyzed for their antibiotic susceptibility patterns. The concentration of Gram negative rods in the samples of enteral feeding solutions ranged from 10(3) to 10(7) CFU/mL, markedly exceeding the permissible level (10(2) CFU/mL or less). The coliforms most ...
International Journal of Infectious Diseases, 2012
Background: Urinary tract infections (UTIs) are the most important cause of morbidity and mortali... more Background: Urinary tract infections (UTIs) are the most important cause of morbidity and mortality in the world affecting all age groups. It is estimated that 150 million cases of UTI occur on a global basis per year. Resistance to antibiotics is highly prevalent and growing as the global problem in management of UTI. Knowledge of pattern of antimicrobial agents among local isolates plays a major role for selecting appropriate and effective therapy. Objectives: The present study was conducted to determine in vitro susceptibility among Gram negative organisms obtained from urineagainst commonly used antimicrobials. Methods: Urine specimens submitted to the Department of Microbiology, BP Koirala Institute of Health Sciences (BPKIHS) Hospital for culture and sensitivity over one year period were evaluated. Isolation, identification and determination of antimicrobial susceptibility were done by standard microbiological techniques. Results: Out of 13011 urine specimens submitted, 2131(16.3%) comprises Gram negative uropathogens, among which the most prevalent was Escherichia coli (66.3%) followed by Klebsilla pneumoniae (11.7%), Acinetobacter anitratus (6.8%), Enterobacter aerogens (3.3%) and Pseudomonas aeruginosa (2.5%), Morganella morganii (1.3%), Proteus mirabilis (1.2%), Citrobacter frundii (0.7%), Klebsiella oxytoca (0.7%), Proteus vulgaris (0.56%). The majority (65.3%) were from female while (34.7%) were male patients. Most of the GNB isolates were found to be resistant to ampicillin (90%), norfloxacillin (60%) and ofloxacin (57.17%) where as they were susceptible to cotrimoxazole (73.2%), nitrofurantoin (69%) and amikacin (68.4%). Conclusion: Gram negative organisms remain the major cause of UTI. Various degree of antimicrobial resistance was observed among the uropathogens prevalent in our hospital. Regular monitoring of the resistance in the local isolates against the routinely used antimicrobial may have significant impact for the effective management of UTI.
and high (December-January) incidence of diarrhea associated with rotavirus, respectively. Lettuc... more and high (December-January) incidence of diarrhea associated with rotavirus, respectively. Lettuce samples were pooled and evaluated for rotavirus by enzyme-linked immunosorbent assay (ELISA) and for Hepatitis A virus by radioimmunoassay, polymerase chain reaction (PCR) and electron microscope. Three sample pools, collected during the period of high prevalence of diarrhea, were positive for rotavirus by ELISA and in one of them rotavirions were visualized by electron microscopy. Two samples pools collected during the same period were positive for Hepatitis A virus as shown by PCR. In almost all the pools fecal coliform bacteria were detected by cultivation and bacteriophages were visualized by electron microscopy.
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