114 research outputs found

    Anterior Urethral Advancement in Repair of Hypospadias: A Modification of the Technique

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    Background/Purpose: Anterior Urethral advancement as one stage technique for hypospadias repair was first described by Ti – Shang Cheng in 1984. It was used for repair of distal and midpenile hypospadias. It was also used for treating secondary cases and urethral fistulae. Stricture, fistulae and ventral curvature were among the complications that faced surgeons on applying the original technique. Materials & Methods: In the period between March1997 and December 2008,140 patients with distal penile hypospadias or anterior urethral fistula were treated with anterior urethral advancement technique with certain modifications. Results: The usual complications of the technique (ventral curvature of the penis, urethral fistula and meatal stenosis) were avoided. Conclusion: This study represents certain modifications that helped to a great extent in improving the results and prevented stricture and fistula formation. Index Word: Hypospadias, fistula, urethral advancemen

    Étude Comparative des ModalitĂ©s de la Prise en Change PĂ©riopĂ©ratoire Nutritionnelle Lors de la Chirurgie Digestive Ă  Soissons (France) et Ă  Tanambao (Madagascar)

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    L’état nutritionnel d’un individu influence sa morbi-mortalitĂ© pĂ©riopĂ©ratoire. Les complications postopĂ©ratoires sont en augmentation jusqu’à 72% chez les patients prĂ©sentant une dĂ©nutrition en pĂ©riopĂ©ratoire contre 29% chez ceux qui ne le sont pas. Le taux de mortalitĂ© pĂ©riopĂ©ratoire en chirurgie digestive chez les sujets dĂ©nutris va jusqu’à 29%.  Objectif : Comparer les modalitĂ©s de prise en charge nutritionnelle pĂ©riopĂ©ratoire en chirurgie digestive dans les centres hospitaliers de Soissons (France) et de Tanambao (Madagascar). Patients et mĂ©thode : Il s’est agi d’une Ă©tude observationnelle prospective sur douze mois (mai 2018 Ă  avril 2019). Les patients bĂ©nĂ©ficiant d’une chirurgie digestive par voie laparotomique mĂ©diane ont Ă©tĂ© inclus. Le test de Mann Whitney Ă©tait utilisĂ© pour la comparaison des variables portant sur les caractĂ©ristiques de la population d’étude, la prise en charge nutritionnelle pĂ©riopĂ©ratoire et la durĂ©e d’hospitalisation (XLSTATÂź 2019.4.2). Une valeur de p infĂ©rieur Ă  0,05 Ă©tait significative.  RĂ©sultats : A Soissons, 47 patients ĂągĂ©s de 63 [32- 100] ans ont Ă©tĂ© inclus, Ă  prĂ©dominance masculine (sex ratio = 1,5). Le jeĂ»ne prĂ©opĂ©ratoire Ă©tait de 8 heures [4- 18]. Dix-huit patients (38,3%) ont bĂ©nĂ©ficiĂ© d’un support nutritionnel pendant 4 jours [2- 14]. En postopĂ©ratoire, les patients ont bĂ©nĂ©ficiĂ© d’un support nutritionnel durant 8 jours [1- 29]. L’alimentation entĂ©rale en postopĂ©ratoire a Ă©tĂ© reprise au 6Ăšme jour [1- 13]. Huit patients ont prĂ©sentĂ© des complications dont un dĂ©cĂ©dĂ©. La durĂ©e totale d’hospitalisation Ă©tait de 10 jours [5- 29]. A Tanambao, 43 patients Ă©taient inclus, ĂągĂ©s de 45 [18- 79] ans. La classe 1 et 2 de l’ASA Ă©taient respectivement Ă  37,2% et Ă  39,5%. Le jeĂ»ne prĂ©opĂ©ratoire durait 10 heures [3- 18]. Neuf patients ont reçu un support nutritionnel prĂ©opĂ©ratoire pendant 3 jours [1- 7]. En postopĂ©ratoire, l’alimentation entĂ©rale a Ă©tĂ© autorisĂ©e au 7Ăšme jour [2- 14], un support nutritionnel Ă©tait administrĂ© pendant 8 jours [3- 15]. Les patients restaient Ă  l’hĂŽpital pendant 15 jours [6- 30]. Conclusion : L’état nutritionnel pĂ©riopĂ©ratoire constitue l’un des dĂ©terminants d’une rĂ©habilitation postopĂ©ratoire optimale. La prescription du support nutritionnel et du jeĂ»ne prĂ©opĂ©ratoire devrait ĂȘtre en fonction du grade nutritionnel et doit couvrir les besoins nutritionnels quotidiens.  A Soissons (France), mais aussi Ă  Tanambao (Madagascar), cette prise en charge nutritionnelle reste Ă  amĂ©liorer suivant les recommandations.   Background: The nutritional state of a patient impacts on perioperative morbidity and mortality. Postoperative complications are up to 72% in patients with perioperative undernutrition against 29% against those who do not present undernutrition. The mortality rate in perioperative digestive surgery in malnourished subjects is up to 29%. Aim: To compare the modalities of perioperative nutritional management of digestive surgery in the hospitals of Soissons and Tanambao. Patients and methods: This is a prospective observational study over 12 months (May 2018 to April 2019). Patients undergoing digestive surgery via midline laparotomy were included. The Mann Whitney test was used to compare variables relating to the characteristics of the study population, perioperative nutritional management and length of hospital stay (XLSTATÂź 2019.4.2). A p- value of less than 0,05 was considered significant. Results: In Soissons, 47 patients aged 63 [32-100] years were included, predominantly male (sex ratio = 1.5). The preoperative fast was 8 hours [4-18]. Eighteen patients (38.3%) received nutritional support for 4 days [2-14]. Postoperatively, patients received nutritional support for 8 days [1-29]. Postoperative enteral feeding was resumed on the 6th day [1-13]. Eight patients presented complications, one of which died. The total duration of hospitalization was 10 days [5-29]. In Tanambao, 43 patients were included, aged 45 [18-79] years. ASA class 1 and 2 were at 37.2% and 39.5% respectively. The preoperative fast lasted 10 hours [3-18]. Nine patients received preoperative nutritional support for 3 days [1-7]. Postoperatively, enteral feeding was authorized on the 7th day [2-14], nutritional support was administered for 8 days [3-15]. The patients stayed in the hospital for 15 days [6-30]. Conclusion: Perioperative nutritional status is one of the elements of good postoperative rehabilitation. The prescription of nutritional support and preoperative fasting should be according to nutritional grade and should cover daily nutritional needs

    Étude Comparative des ModalitĂ©s de la Price en Charge PĂ©riopĂ©ratore Nutritionnelle Lors de la Chirurgie Digestive Ă  Soissons (France) et Ă  Tanambao (Madagascar)

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    L’état nutritionnel d’un individu influence sur sa morbi-mortalitĂ© pĂ©riopĂ©ratoire. Les complications postopĂ©ratoires sont en augmentation jusqu’à 72% chez les patients prĂ©sentant une dĂ©nutrition en pĂ©riopĂ©ratoire contre 29% chez ceux qui ne le sont pas. Le taux de mortalitĂ© en pĂ©riopĂ©ratoire de chirurgie digestive chez les sujets dĂ©nutris va jusqu’à 29%.  Objectif : Comparer les modalitĂ©s de prise en charge nutritionnelle pĂ©riopĂ©ratoire de chirurgie digestive dans les centres hospitaliers de Soissons (France) et de Tanambao (Madagascar). Patients et mĂ©thode : Il s’agit d’une Ă©tude observationnelle prospective sur douze mois (mai 2018 Ă  avril 2019). Les patients bĂ©nĂ©ficiant d’une chirurgie digestive par voie laparotomie mĂ©diane ont Ă©tĂ© inclus. Le test de Mann Whitney Ă©tait utilisĂ© pour la comparaison des variables portant sur les caractĂ©ristiques de la population d’étude, la prise en charge nutritionnelle pĂ©riopĂ©ratoire et la durĂ©e d’hospitalisation (XLSTATÂź 2019.4.2). Une valeur de p infĂ©rieur Ă  0,05 Ă©tait significative.  RĂ©sultats : Quarante-sept patients ĂągĂ©s de 63 [32- 100] ans ont Ă©tĂ© retenus Ă  Soissons et 43 patients, ĂągĂ©s de 45 [18- 79] ans, Ă  Tanambao. La population d’étude Ă©tait Ă  prĂ©dominance masculine (sex ratio = 1,5 Ă  Soissons et 2,1 Ă  Toliara). La durĂ©e du jeĂ»ne prĂ©opĂ©ratoire (<2h versus ≄6h ; p<0,001), l’apport protĂ©ino-Ă©nergĂ©tique prĂ©opĂ©ratoire (<25 kcal/kg/j versus sans apport ; p= 0,041 et apport protĂ©ique <1 g/kg/j versus sans apport ; p<0,001), l’apport protĂ©ino-Ă©nergĂ©tique postopĂ©ratoire ([25- 30 Kcal/kg/j versus <25 Kcal/kg/j ; p<0,001 et apport protĂ©ique [1- 1,5 g/kg/j versus <1 g/kg/j ; p<0,001) et la durĂ©e d’hospitalisation (10j versus 14j ; p<0,001) Ă©taient diffĂ©rents entre les deux centres hospitaliers. Le grade nutritionnel (GN 2, p= 0,244) et la morbi-mortalitĂ© Ă©taient comparables entre les deux centres hospitaliers (absence de complications, p= 0,817). Conclusion : L’état nutritionnel pĂ©riopĂ©ratoire constitue l’un des dĂ©terminants d’une rĂ©habilitation postopĂ©ratoire optimale. La prescription du support nutritionnel et du jeĂ»ne prĂ©opĂ©ratoire devrait ĂȘtre en fonction du grade nutritionnel et doit couvrir les besoins nutritionnels quotidiens.  A Soissons (France), mais aussi Ă  Tanambao (Madagascar), cette prise en charge nutritionnelle reste Ă  amĂ©liorer suivant les recommandations. L’état nutritionnel d’un individu influence sur sa morbi-mortalitĂ© pĂ©riopĂ©ratoire. Les complications postopĂ©ratoires sont en augmentation jusqu’à 72% chez les patients prĂ©sentant une dĂ©nutrition en pĂ©riopĂ©ratoire contre 29% chez ceux qui ne le sont pas. Le taux de mortalitĂ© en pĂ©riopĂ©ratoire de chirurgie digestive chez les sujets dĂ©nutris va jusqu’à 29%.   Objectif : Comparer les modalitĂ©s de prise en charge nutritionnelle pĂ©riopĂ©ratoire de chirurgie digestive dans les centres hospitaliers de Soissons (France) et de Tanambao (Madagascar). Patients et mĂ©thode : Il s’agit d’une Ă©tude observationnelle prospective sur douze mois (mai 2018 Ă  avril 2019). Les patients bĂ©nĂ©ficiant d’une chirurgie digestive par voie laparotomie mĂ©diane ont Ă©tĂ© inclus. Le test de Mann Whitney Ă©tait utilisĂ© pour la comparaison des variables portant sur les caractĂ©ristiques de la population d’étude, la prise en charge nutritionnelle pĂ©riopĂ©ratoire et la durĂ©e d’hospitalisation (XLSTATÂź 2019.4.2). Une valeur de p infĂ©rieur Ă  0,05 Ă©tait significative.  RĂ©sultats : Quarante-sept patients ĂągĂ©s de 63 [32- 100] ans ont Ă©tĂ© retenus Ă  Soissons et 43 patients, ĂągĂ©s de 45 [18- 79] ans, Ă  Tanambao. La population d’étude Ă©tait Ă  prĂ©dominance masculine (sex ratio = 1,5 Ă  Soissons et 2,1 Ă  Toliara). La durĂ©e du jeĂ»ne prĂ©opĂ©ratoire (<2h versus ≄6h ; p<0,001), l’apport protĂ©ino-Ă©nergĂ©tique prĂ©opĂ©ratoire (<25 kcal/kg/j versus sans apport ; p= 0,041 et apport protĂ©ique <1 g/kg/j versus sans apport ; p<0,001), l’apport protĂ©ino-Ă©nergĂ©tique postopĂ©ratoire ([25- 30 Kcal/kg/j versus <25 Kcal/kg/j ; p<0,001 et apport protĂ©ique [1- 1,5 g/kg/j versus <1 g/kg/j ; p<0,001) et la durĂ©e d’hospitalisation (10j versus 14j ; p<0,001) Ă©taient diffĂ©rents entre les deux centres hospitaliers. Le grade nutritionnel (GN 2, p= 0,244) et la morbi-mortalitĂ© Ă©taient comparables entre les deux centres hospitaliers (absence de complications, p= 0,817). Conclusion :L’état nutritionnel pĂ©riopĂ©ratoire constitue l’un des dĂ©terminants d’une rĂ©habilitation postopĂ©ratoire optimale. La prescription du support nutritionnel et du jeĂ»ne prĂ©opĂ©ratoire devrait ĂȘtre en fonction du grade nutritionnel et doit couvrir les besoins nutritionnels quotidiens.  A Soissons (France), mais aussi Ă  Tanambao (Madagascar), cette prise en charge nutritionnelle reste Ă  amĂ©liorer suivant les recommandations.   Background: The nutritional state of a patient impacts on perioperative morbidity and mortality. Postoperative complications are up to 72% in patients with perioperative undernutrition against 29% against those who do not present undernutrition. The mortality rate in perioperative digestive surgery in malnourished subjects is up to 29%. Aim: To compare the modalities of perioperative nutritional management of digestive surgery in the hospitals of Soissons and Tanambao. Patients and methods: This is a prospective observational study over 12 months (May 2018 to April 2019). Patients undergoing digestive surgery via midline laparotomy were included. The Mann Whitney test was used to compare variables relating to the characteristics of the study population, perioperative nutritional management and length of hospital stay (XLSTATÂź 2019.4.2). A p- value of less than 0,05 was considered significant. Results: Forty- seven patients aged 63 [32- 100] years old were retained in Soissons while the study population was 43 (aged 45 [18- 79] years old) in Tanambao. The study population was mostly male (sex ratio = 1,5 in Soissons and 2,1 in Toliara). The duration of the preoperative fast (<2h versus ≄6h ; p<0,001), the preoperative protein-energy intake (<25 kcal/kg/day versus no intake ; p= 0,041 and energy intake <1 g/kg/day versus no intake ; p<0,001), the postoperative protein-energy intake ([25- 30 kcal/kg/day versus <25 kcal/kg/day ; p<0,001 and and energy intake [1- 1,5  g/kg/day versus <1 g/kg/day ; p<0,001), and length of hospitalization (10 days versus 14 days ; p<0,001) were different between the two hospitals. The nutritional grade (NG 2, p= 0,244) and morbidity and mortality were comparable between the two groups (absence of complications, p= 0,817). Conclusion: Perioperative nutritional status is one of the elements of good postoperative rehabilitation. The prescription of nutritional support and preoperative fasting should be according to nutritional grade and should cover daily nutritional needs

    Étude Comparative des ModalitĂ©s de la Price en Charge PĂ©riopĂ©ratore Nutritionnelle Lors de la Chirurgie Digestive Ă  Soissons (France) et Ă  Tanambao (Madagascar)

    Get PDF
    L’état nutritionnel d’un individu influence sur sa morbi-mortalitĂ© pĂ©riopĂ©ratoire. Les complications postopĂ©ratoires sont en augmentation jusqu’à 72% chez les patients prĂ©sentant une dĂ©nutrition en pĂ©riopĂ©ratoire contre 29% chez ceux qui ne le sont pas. Le taux de mortalitĂ© en pĂ©riopĂ©ratoire de chirurgie digestive chez les sujets dĂ©nutris va jusqu’à 29%.  Objectif : Comparer les modalitĂ©s de prise en charge nutritionnelle pĂ©riopĂ©ratoire de chirurgie digestive dans les centres hospitaliers de Soissons (France) et de Tanambao (Madagascar). Patients et mĂ©thode : Il s’agit d’une Ă©tude observationnelle prospective sur douze mois (mai 2018 Ă  avril 2019). Les patients bĂ©nĂ©ficiant d’une chirurgie digestive par voie laparotomie mĂ©diane ont Ă©tĂ© inclus. Le test de Mann Whitney Ă©tait utilisĂ© pour la comparaison des variables portant sur les caractĂ©ristiques de la population d’étude, la prise en charge nutritionnelle pĂ©riopĂ©ratoire et la durĂ©e d’hospitalisation (XLSTATÂź 2019.4.2). Une valeur de p infĂ©rieur Ă  0,05 Ă©tait significative.  RĂ©sultats : Quarante-sept patients ĂągĂ©s de 63 [32- 100] ans ont Ă©tĂ© retenus Ă  Soissons et 43 patients, ĂągĂ©s de 45 [18- 79] ans, Ă  Tanambao. La population d’étude Ă©tait Ă  prĂ©dominance masculine (sex ratio = 1,5 Ă  Soissons et 2,1 Ă  Toliara). La durĂ©e du jeĂ»ne prĂ©opĂ©ratoire (<2h versus ≄6h ; p<0,001), l’apport protĂ©ino-Ă©nergĂ©tique prĂ©opĂ©ratoire (<25 kcal/kg/j versus sans apport ; p= 0,041 et apport protĂ©ique <1 g/kg/j versus sans apport ; p<0,001), l’apport protĂ©ino-Ă©nergĂ©tique postopĂ©ratoire ([25- 30 Kcal/kg/j versus <25 Kcal/kg/j ; p<0,001 et apport protĂ©ique [1- 1,5 g/kg/j versus <1 g/kg/j ; p<0,001) et la durĂ©e d’hospitalisation (10j versus 14j ; p<0,001) Ă©taient diffĂ©rents entre les deux centres hospitaliers. Le grade nutritionnel (GN 2, p= 0,244) et la morbi-mortalitĂ© Ă©taient comparables entre les deux centres hospitaliers (absence de complications, p= 0,817). Conclusion : L’état nutritionnel pĂ©riopĂ©ratoire constitue l’un des dĂ©terminants d’une rĂ©habilitation postopĂ©ratoire optimale. La prescription du support nutritionnel et du jeĂ»ne prĂ©opĂ©ratoire devrait ĂȘtre en fonction du grade nutritionnel et doit couvrir les besoins nutritionnels quotidiens.  A Soissons (France), mais aussi Ă  Tanambao (Madagascar), cette prise en charge nutritionnelle reste Ă  amĂ©liorer suivant les recommandations. L’état nutritionnel d’un individu influence sur sa morbi-mortalitĂ© pĂ©riopĂ©ratoire. Les complications postopĂ©ratoires sont en augmentation jusqu’à 72% chez les patients prĂ©sentant une dĂ©nutrition en pĂ©riopĂ©ratoire contre 29% chez ceux qui ne le sont pas. Le taux de mortalitĂ© en pĂ©riopĂ©ratoire de chirurgie digestive chez les sujets dĂ©nutris va jusqu’à 29%.   Objectif : Comparer les modalitĂ©s de prise en charge nutritionnelle pĂ©riopĂ©ratoire de chirurgie digestive dans les centres hospitaliers de Soissons (France) et de Tanambao (Madagascar). Patients et mĂ©thode : Il s’agit d’une Ă©tude observationnelle prospective sur douze mois (mai 2018 Ă  avril 2019). Les patients bĂ©nĂ©ficiant d’une chirurgie digestive par voie laparotomie mĂ©diane ont Ă©tĂ© inclus. Le test de Mann Whitney Ă©tait utilisĂ© pour la comparaison des variables portant sur les caractĂ©ristiques de la population d’étude, la prise en charge nutritionnelle pĂ©riopĂ©ratoire et la durĂ©e d’hospitalisation (XLSTATÂź 2019.4.2). Une valeur de p infĂ©rieur Ă  0,05 Ă©tait significative.  RĂ©sultats : Quarante-sept patients ĂągĂ©s de 63 [32- 100] ans ont Ă©tĂ© retenus Ă  Soissons et 43 patients, ĂągĂ©s de 45 [18- 79] ans, Ă  Tanambao. La population d’étude Ă©tait Ă  prĂ©dominance masculine (sex ratio = 1,5 Ă  Soissons et 2,1 Ă  Toliara). La durĂ©e du jeĂ»ne prĂ©opĂ©ratoire (<2h versus ≄6h ; p<0,001), l’apport protĂ©ino-Ă©nergĂ©tique prĂ©opĂ©ratoire (<25 kcal/kg/j versus sans apport ; p= 0,041 et apport protĂ©ique <1 g/kg/j versus sans apport ; p<0,001), l’apport protĂ©ino-Ă©nergĂ©tique postopĂ©ratoire ([25- 30 Kcal/kg/j versus <25 Kcal/kg/j ; p<0,001 et apport protĂ©ique [1- 1,5 g/kg/j versus <1 g/kg/j ; p<0,001) et la durĂ©e d’hospitalisation (10j versus 14j ; p<0,001) Ă©taient diffĂ©rents entre les deux centres hospitaliers. Le grade nutritionnel (GN 2, p= 0,244) et la morbi-mortalitĂ© Ă©taient comparables entre les deux centres hospitaliers (absence de complications, p= 0,817). Conclusion :L’état nutritionnel pĂ©riopĂ©ratoire constitue l’un des dĂ©terminants d’une rĂ©habilitation postopĂ©ratoire optimale. La prescription du support nutritionnel et du jeĂ»ne prĂ©opĂ©ratoire devrait ĂȘtre en fonction du grade nutritionnel et doit couvrir les besoins nutritionnels quotidiens.  A Soissons (France), mais aussi Ă  Tanambao (Madagascar), cette prise en charge nutritionnelle reste Ă  amĂ©liorer suivant les recommandations.   Background: The nutritional state of a patient impacts on perioperative morbidity and mortality. Postoperative complications are up to 72% in patients with perioperative undernutrition against 29% against those who do not present undernutrition. The mortality rate in perioperative digestive surgery in malnourished subjects is up to 29%. Aim: To compare the modalities of perioperative nutritional management of digestive surgery in the hospitals of Soissons and Tanambao. Patients and methods: This is a prospective observational study over 12 months (May 2018 to April 2019). Patients undergoing digestive surgery via midline laparotomy were included. The Mann Whitney test was used to compare variables relating to the characteristics of the study population, perioperative nutritional management and length of hospital stay (XLSTATÂź 2019.4.2). A p- value of less than 0,05 was considered significant. Results: Forty- seven patients aged 63 [32- 100] years old were retained in Soissons while the study population was 43 (aged 45 [18- 79] years old) in Tanambao. The study population was mostly male (sex ratio = 1,5 in Soissons and 2,1 in Toliara). The duration of the preoperative fast (<2h versus ≄6h ; p<0,001), the preoperative protein-energy intake (<25 kcal/kg/day versus no intake ; p= 0,041 and energy intake <1 g/kg/day versus no intake ; p<0,001), the postoperative protein-energy intake ([25- 30 kcal/kg/day versus <25 kcal/kg/day ; p<0,001 and and energy intake [1- 1,5  g/kg/day versus <1 g/kg/day ; p<0,001), and length of hospitalization (10 days versus 14 days ; p<0,001) were different between the two hospitals. The nutritional grade (NG 2, p= 0,244) and morbidity and mortality were comparable between the two groups (absence of complications, p= 0,817). Conclusion: Perioperative nutritional status is one of the elements of good postoperative rehabilitation. The prescription of nutritional support and preoperative fasting should be according to nutritional grade and should cover daily nutritional needs

    Cephalometric norms for the Saudi children living in the western region of Saudi Arabia: a research report

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    BACKGROUND: Previous studies have established specific cephalometric norms for children with different ethnic backgrounds, showing different facial features for each group. Up till now, there is a paucity of information about the cephalometric features of Saudi children living in the western region of Saudi Arabia, who have distinct social and climatic characteristics. The aim of the present study was to establish cephalometric norms for children living in the western region of Saudi Arabia. METHODS: A total of 62 lateral cephalometric radiographs of Saudis (33 females and 29 males; aged 9–12 years) having good facial proportions and Class I dental occlusion, were traced and analyzed. Using the t-test, the mean value, standard deviation and the range of 20 angular and linear variables were calculated and compared to norms of adult Saudis living in the Western region of Saudi Arabia using the t-test. Male and female groups were also compared using the t- test. RESULTS: Saudi children tend to have a significantly shorter and lower face height, a larger angle of convexity, and more proclined and protruded incisors when compared with adult Saudis (P < 0.05). There were no statistically significant differences between male and female groups. CONCLUSION: Saudi children have distinct cephalometric features, which should be used as a reference in the orthodontic treatment of young Saudi patients

    A differential equation for a class of discrete lifetime distributions with an application in reliability: A demonstration of the utility of computer algebra

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    YesIt is shown that the probability generating function of a lifetime random variable T on a finite lattice with polynomial failure rate satisfies a certain differential equation. The interrelationship with Markov chain theory is highlighted. The differential equation gives rise to a system of differential equations which, when inverted, can be used in the limit to express the polynomial coefficients in terms of the factorial moments of T. This then can be used to estimate the polynomial coefficients. Some special cases are worked through symbolically using Computer Algebra. A simulation study is used to validate the approach and to explore its potential in the reliability context

    The mechanisms by which polyamines accelerate tumor spread

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    Increased polyamine concentrations in the blood and urine of cancer patients reflect the enhanced levels of polyamine synthesis in cancer tissues arising from increased activity of enzymes responsible for polyamine synthesis. In addition to their de novo polyamine synthesis, cells can take up polyamines from extracellular sources, such as cancer tissues, food, and intestinal microbiota. Because polyamines are indispensable for cell growth, increased polyamine availability enhances cell growth. However, the malignant potential of cancer is determined by its capability to invade to surrounding tissues and metastasize to distant organs. The mechanisms by which increased polyamine levels enhance the malignant potential of cancer cells and decrease anti-tumor immunity are reviewed. Cancer cells with a greater capability to synthesize polyamines are associated with increased production of proteinases, such as serine proteinase, matrix metalloproteinases, cathepsins, and plasminogen activator, which can degrade surrounding tissues. Although cancer tissues produce vascular growth factors, their deregulated growth induces hypoxia, which in turn enhances polyamine uptake by cancer cells to further augment cell migration and suppress CD44 expression. Increased polyamine uptake by immune cells also results in reduced cytokine production needed for anti-tumor activities and decreases expression of adhesion molecules involved in anti-tumor immunity, such as CD11a and CD56. Immune cells in an environment with increased polyamine levels lose anti-tumor immune functions, such as lymphokine activated killer activities. Recent investigations revealed that increased polyamine availability enhances the capability of cancer cells to invade and metastasize to new tissues while diminishing immune cells' anti-tumor immune functions

    Parameter induction in continuous univariate distributions: Well-established G families

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