Background Currently, gastrectomy and extended lymphadenectomy (LN) is the treatment of choice fo... more Background Currently, gastrectomy and extended lymphadenectomy (LN) is the treatment of choice for gastric cancer. Although a survival rate benefit of D2 LN compared to D1 LN has been shown, the D2 LN procedure is not fully employed, due to possible higher morbidity and mortality rates. These higher rates are being questioned in more recent series, in which D1 and D2 LN complication rates have been similar. The aim of this study was to analyze the immediate postoperative complications of patients submitted to total or subtotal gastrectomy with D1 or D2 LN (according to the Japanese guidelines for gastric cancer) at the Gastrointestinal Surgery Division of the Medical School of São Paulo University, between January 2001 and April 2003. Methods One hundred consecutive patients were studied; 61 were men and 39, women. Total gastrectomy was performed in 52 patients (13 with D1 LN and 39 with D2 LN), and subtotal gastrectomy was performed in 48 (11 with D1 LN and 37 with D2 LN). Total or subtotal gastrectomy with D1 or D2 LN was performed according to the tumor extent and histological classification (Lauren’s diffuse or intestinal type), considering the patient’s general condition and the gastric cancer stage. Roux-en-Y reconstruction was performed in almost all patients. Results No difference was observed regarding complications and mortality related to the extent of the gastrectomy. Although morbidity was higher in the D1 group, no significant difference was observed. Mortality was higher in the D1 group, and this was probably related to their poor surgical condition and more advanced tumors. Conclusion According to these results, it appears that total or subtotal gastrectomy with D2 LN in gastric cancer treatment, performed according to the Japanese guidelines, can be considered a safe procedure, with acceptable morbidity and mortality, when performed by a trained surgical team.
Extracts from young leaves of nine sweet cherry (Prunus avium L.) and eight sour cherry (Prunus c... more Extracts from young leaves of nine sweet cherry (Prunus avium L.) and eight sour cherry (Prunus cerasus L.) varieties, located in the germplasm collection of the 'Direção Regional de Agricultura da Beira Interior' (Fundão, Portugal), were analysed for five isozyme systems in order to characterise these varieties and detect problems of synonymies and homonymies that frequently present. The sweet and sour cherry varieties analyzed showed low isoenzymatic polymorphism, being PGM and PGI the systems with the highest discrimination power. These systems presented seven and five different zymogrames, respectively. IDH showed four patterns. SKDH and 6-PGD grouped the varieties only into two patterns. The evident and discriminant restrictions of this type of analysis had got results that have only been a complement for agronomical and morphological characterization.
Negative-pressure pulmonary edema after endotracheal intubation is an uncommon and potentially se... more Negative-pressure pulmonary edema after endotracheal intubation is an uncommon and potentially serious complication of patients undergoing general anesthesia for different surgical procedures. We report a case of a healthy 20-year-old male patient with the diagnosis of acute appendicitis. The patient was submitted to appendectomy under general anesthesia and developed negative-pressure pulmonary edema immediately after extubation. The present paper reports this potentially serious complication illustrating the main radiological findings consistent with alveolar hemorrhage in this setting and the treatment performed. (Curr Surg 61:463-465.
Background Familial adenomatous polyposis (FAP) is a genetic disease characterized by multiple ad... more Background Familial adenomatous polyposis (FAP) is a genetic disease characterized by multiple adenomatous colorectal polyps and different extracolonic manifestations (ECM). The present work is aimed to analyze the outcome after surgical treatment regarding complications and cancer recurrence. Methods Charts from patients treated between 1977 and 2006 were retrospectively analyzed. Clinical and endoscopic data, results of treatment, pathological reports and information about recurrence were collected. Results Eighty-eight patients (41 men [46.6%] and 47 women [53.4%]) were assisted. At diagnosis, associated colorectal cancer (CRC) was detected in 53 patients (60.2%), whose average age was higher than those without CRC (40.0 vs. 29.5 years). At colonoscopy, polyposis was classified as attenuated in 12 patients (14.3%). Surgical treatment consisted in total proctocolectomy with ileostomy (PCI, 15 [17.4%]), restorative proctocolectomy (RPC, 27 [31.4%]), total colectomy with ileal-rectum anastomosis (IRA, 42 [48.8%]), palliative segmental resection (1 [1.2%]) and internal bypass (1 [1.2%]). Two patients were not operated on due to religious reasons and advanced disease. Complications occurred in 25 patients (29.0%), more commonly after RPC (48.1%). There was no operative mortality. Local or distant metastases were detected in six (11.3%) patients with CRC treated to cure. During the follow-up of 36 IRA, cancer developed in the rectal cuff in six patients (16.6%), whose average age was higher than in patients without rectal recurrence (45.8 vs. 36.6 years). Five of them have had colonic cancer in the resected specimen. Among the 26 patients followed after RPC, cancer in the ileal pouch developed in 1 (3.8%). Conclusions (1) Within the present series, FAP patients presented a high incidence of associated CRC and diagnosis was generally established after the third decade of life; (2) operative complications occurred in about one third of the patients, being more frequent after the confection of an ileal reservoir; (3) rectal cancer after IRA was detected in 16.6% of patients and it was associated with greater age and previous colonic carcinoma; (4) both continuous and long-term surveillance of the rectal stump and ileal pouch are necessary during follow-up.
Background The role of local excision for pT2 distal rectal cancer has been challenged because of... more Background The role of local excision for pT2 distal rectal cancer has been challenged because of the observation of high rates of lymph node metastases and local failure. However, neoadjuvant chemoradiation therapy (CRT) has led to increased local disease control and significant tumor downstaging, possibly decreasing rates of lymph node metastases. In this setting, a possible role for local excision of ypT2 has been suggested. Methods A total of 401 patients with distal rectal cancer underwent neoadjuvant CRT. Tumor response assessment was performed after at least 8 weeks from CRT completion. One hundred and twelve patients with complete clinical response were not immediately operated on and were excluded from the study, and 289 patients with incomplete clinical response were managed by radical surgery. Patients with final pathological stage ypT2 were analyzed to determine the risk of unfavorable pathological features that could represent unacceptable risk for local failure after local excision. Results Eighty-eight (30%) patients had ypT2 rectal cancer. Final ypT status was not associated with pretreatment radiological staging (p = 0.62). ypT status was significantly associated with the risk of lymph node metastases, risk of perineural and vascular invasion, and recurrence (p = 0.001). Lymph node metastases were present in 19% of patients with ypT2 rectal cancer. The risk of lymph node metastases in ypT2 was associated with the presence of perineural invasion (47% vs 4%; p = <0.001), vascular invasion (59% vs 6%; p < 0.001), and decreased mean interval CRT surgery (12 vs 18 weeks; p < 0.001), but not with mean tumor size (3.2 vs 3.1 cm; p = 0.8). Disease-free and overall survival rates were significantly better for patients with ypT2N0 (p = 0.02 and 0.006, respectively). Fifty-five (63%) patients with ypT2 had at least one unfavorable pathological feature for local excision (lymph node metastases, vascular or perineural invasion, mucinous type or tumor size >3 cm). Conclusion Lymph node metastases were present in 19% of patients with ypT2 and were significantly associated with poor overall and disease-free survival rates. The risk of lymph node metastases could not be predicted by radiological staging or tumor size. Radical surgery should be considered the standard treatment option for ypT2 rectal cancer after CRT.
Objective The objective was to determine the presence and frequency of micrometastasis in lymph n... more Objective The objective was to determine the presence and frequency of micrometastasis in lymph nodes of patients with rectal cancer treated by preoperative chemoradiation followed by curative resection. Patients and methods All 56 patients included were treated with 5-FU and leucovorin plus 5,040 cGy, followed by radical surgery and were diagnosed with stage II distal rectal adenocarcinoma after complete pathological examination (ypT3-4N0M0). Immunohistochemistry was assessed with cytokeratin monoclonal antibody AE1/AE3. Three 4-μm paraffin sections were obtained from each lymph node, cut at 50 μm apart from each other. The results were reviewed by two independent pathologists. Results Mean number of lymph nodes was 9.6 per patient. Four patients (7%) and seven lymph nodes (1.35%) were positive for micrometastasis. Three patients had pT3 and one a pT4 tumor. One of the patients had positive micrometastasis and the presence of mucinous deposits. One other patient had mucinous deposits without any micrometastasis. All four patients are alive with no evidence of recurrent disease. Fourteen patients negative for micrometastasis had recurrent disease (25%), eight systemic (14.7%) and six locoregional (10.3%). There were two cancer-related deaths. The mean follow-up period was 39 months. Conclusion Patients with rectal cancer treated by preoperative chemoradiation showed a surprisingly low rate of micrometastasis detection (7%), even in high-risk patients (T3 and T4 tumors). Lymph node micrometastasis was not associated with decreased overall or disease-free survival. The identification of mucinous deposits on lymph nodes with no viable tumor cells may be direct evidence of lymph node downstaging. The downstaging effect of preoperative chemoradiation therapy may be significant in reducing even micrometastasis detection in low rectal cancer managed by this treatment strategy.
The present study examined the effects of 5-HT 1A and 5-HT 2C receptor agonists on behavioral sat... more The present study examined the effects of 5-HT 1A and 5-HT 2C receptor agonists on behavioral satiety sequence (BSS) in rats. The 5-HT 1A receptor agonist, 8-OH-DPAT (0.5 g), and the 5-HT 2C receptor agonist, Ro-60-0175 (3.0 g), were injected into the paraventricular nucleus (PVN) of rats. The animals were maintained on an ad libitum feeding paradigm with access to water and individual sources of protein, carbohydrate, and fat. Intra-PVN administration of each agonist was associated with decreased carbohydrate consumption. The effect was enhanced by the administration of both agonists together. Behavioral analysis indicated that co-administration of 8-OH-DPAT and Ro-60-0175 interrupted the natural BSS with an increase in non-feeding behavior, whereas the 8-OH-DPAT alone promoted early development of the natural BSS. In conclusion, the 5-HT receptor agonists affected serotonergic modulation of feeding behavior in a functionally selective way.
Aortoenteric fistula is defined as a communication between the aorta and any adjacent segment of ... more Aortoenteric fistula is defined as a communication between the aorta and any adjacent segment of the bowel. It may be primary or secondary. The former occurs de novo in patients with intestinal or vascular diseases, whereas secondary aortoenteric fistula is a rare and dreadful complication of aortic reconstruction with vascular prosthesis. We report a case of a 62-year-old man who presented to the emergency department with acute rectal bleeding. The patient had previous aortoiliac surgery with the utilization of an aorto-bifemoral vascular graft. Diagnosis of secondary aortoenteric fistula was made between the aortoiliac graft and sigmoid colon. After exploratory laparotomy, Hartmann's procedure, excision of the graft, oversewing of the aortic stump, and axilobifemoral bypass were successfully performed. This study reports a rare type of secondary aortoenteric fistula to the left colon, and it describes an unusual and successful surgical treatment. (Curr Surg 62:49-54.
American Journal of Clinical Oncology-cancer Clinical Trials, 2007
Fatigue is a common symptom in cancer patients receiving radiation therapy. We conducted a double... more Fatigue is a common symptom in cancer patients receiving radiation therapy. We conducted a double-blind randomized crossover trial of multivitamins versus placebo in patients with breast cancer undergoing radiation therapy to evaluate fatigue and quality of life. : We randomized 40 patients to either placebo or Centrum Silver. At the middle of the radiation treatments, patients were switched from placebo to multivitamins and vice versa. Patients answered the EORTC QLQ C-30 quality of life (QOL) and Chalder fatigue questionnaires at the beginning, middle, and end of radiation therapy. Both groups experienced decreases in general (P = 0.009; P = 0.001) and physical fatigue scores (P = 0.031; P = 0.029) at the end of the course of placebo compared with the assessment prior to this treatment. We also observed significant improvements in functional (P = 0.026) and symptoms (P = 0.016) score scales of the QOL questionnaire in the patients on placebo. No significant changes were elicited with the use of multivitamins. We also observed significantly lower rates of fatigue in the patients who had just finished a course of placebo as compared with patients finishing a course of multivitamins (0 vs. 25% P = 0.035). Multivitamins do not improve radiation-related fatigue in patients with breast cancer.
Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperi... more Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperiodic critical orbit have intermediate growth. We illustrate some of the difficulties that arise in attacking this conjecture and prove subexponential growth for the iterated monodromy group of $z^2+i$. This is the first non-trivial example supporting the conjecture.
Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperi... more Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperiodic critical orbit have intermediate growth. We illustrate some of the difficulties that arise in attacking this conjecture and prove subexponential growth for the iterated monodromy group of $z^2+i$. This is the first non-trivial example supporting the conjecture.
Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperi... more Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperiodic critical orbit have intermediate growth. We illustrate some of the difficulties that arise in attacking this conjecture and prove subexponential growth for the iterated monodromy group of $z^2+i$. This is the first non-trivial example supporting the conjecture.
Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperi... more Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperiodic critical orbit have intermediate growth. We illustrate some of the difficulties that arise in attacking this conjecture and prove subexponential growth for the iterated monodromy group of $z^2+i$. This is the first non-trivial example supporting the conjecture.
Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperi... more Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperiodic critical orbit have intermediate growth. We illustrate some of the difficulties that arise in attacking this conjecture and prove subexponential growth for the iterated monodromy group of $z^2+i$. This is the first non-trivial example supporting the conjecture.
Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperi... more Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperiodic critical orbit have intermediate growth. We illustrate some of the difficulties that arise in attacking this conjecture and prove subexponential growth for the iterated monodromy group of $z^2+i$. This is the first non-trivial example supporting the conjecture.
Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperi... more Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperiodic critical orbit have intermediate growth. We illustrate some of the difficulties that arise in attacking this conjecture and prove subexponential growth for the iterated monodromy group of $z^2+i$. This is the first non-trivial example supporting the conjecture.
Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperi... more Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperiodic critical orbit have intermediate growth. We illustrate some of the difficulties that arise in attacking this conjecture and prove subexponential growth for the iterated monodromy group of $z^2+i$. This is the first non-trivial example supporting the conjecture.
Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperi... more Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperiodic critical orbit have intermediate growth. We illustrate some of the difficulties that arise in attacking this conjecture and prove subexponential growth for the iterated monodromy group of $z^2+i$. This is the first non-trivial example supporting the conjecture.
Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperi... more Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperiodic critical orbit have intermediate growth. We illustrate some of the difficulties that arise in attacking this conjecture and prove subexponential growth for the iterated monodromy group of $z^2+i$. This is the first non-trivial example supporting the conjecture.
Background Currently, gastrectomy and extended lymphadenectomy (LN) is the treatment of choice fo... more Background Currently, gastrectomy and extended lymphadenectomy (LN) is the treatment of choice for gastric cancer. Although a survival rate benefit of D2 LN compared to D1 LN has been shown, the D2 LN procedure is not fully employed, due to possible higher morbidity and mortality rates. These higher rates are being questioned in more recent series, in which D1 and D2 LN complication rates have been similar. The aim of this study was to analyze the immediate postoperative complications of patients submitted to total or subtotal gastrectomy with D1 or D2 LN (according to the Japanese guidelines for gastric cancer) at the Gastrointestinal Surgery Division of the Medical School of São Paulo University, between January 2001 and April 2003. Methods One hundred consecutive patients were studied; 61 were men and 39, women. Total gastrectomy was performed in 52 patients (13 with D1 LN and 39 with D2 LN), and subtotal gastrectomy was performed in 48 (11 with D1 LN and 37 with D2 LN). Total or subtotal gastrectomy with D1 or D2 LN was performed according to the tumor extent and histological classification (Lauren’s diffuse or intestinal type), considering the patient’s general condition and the gastric cancer stage. Roux-en-Y reconstruction was performed in almost all patients. Results No difference was observed regarding complications and mortality related to the extent of the gastrectomy. Although morbidity was higher in the D1 group, no significant difference was observed. Mortality was higher in the D1 group, and this was probably related to their poor surgical condition and more advanced tumors. Conclusion According to these results, it appears that total or subtotal gastrectomy with D2 LN in gastric cancer treatment, performed according to the Japanese guidelines, can be considered a safe procedure, with acceptable morbidity and mortality, when performed by a trained surgical team.
Extracts from young leaves of nine sweet cherry (Prunus avium L.) and eight sour cherry (Prunus c... more Extracts from young leaves of nine sweet cherry (Prunus avium L.) and eight sour cherry (Prunus cerasus L.) varieties, located in the germplasm collection of the 'Direção Regional de Agricultura da Beira Interior' (Fundão, Portugal), were analysed for five isozyme systems in order to characterise these varieties and detect problems of synonymies and homonymies that frequently present. The sweet and sour cherry varieties analyzed showed low isoenzymatic polymorphism, being PGM and PGI the systems with the highest discrimination power. These systems presented seven and five different zymogrames, respectively. IDH showed four patterns. SKDH and 6-PGD grouped the varieties only into two patterns. The evident and discriminant restrictions of this type of analysis had got results that have only been a complement for agronomical and morphological characterization.
Negative-pressure pulmonary edema after endotracheal intubation is an uncommon and potentially se... more Negative-pressure pulmonary edema after endotracheal intubation is an uncommon and potentially serious complication of patients undergoing general anesthesia for different surgical procedures. We report a case of a healthy 20-year-old male patient with the diagnosis of acute appendicitis. The patient was submitted to appendectomy under general anesthesia and developed negative-pressure pulmonary edema immediately after extubation. The present paper reports this potentially serious complication illustrating the main radiological findings consistent with alveolar hemorrhage in this setting and the treatment performed. (Curr Surg 61:463-465.
Background Familial adenomatous polyposis (FAP) is a genetic disease characterized by multiple ad... more Background Familial adenomatous polyposis (FAP) is a genetic disease characterized by multiple adenomatous colorectal polyps and different extracolonic manifestations (ECM). The present work is aimed to analyze the outcome after surgical treatment regarding complications and cancer recurrence. Methods Charts from patients treated between 1977 and 2006 were retrospectively analyzed. Clinical and endoscopic data, results of treatment, pathological reports and information about recurrence were collected. Results Eighty-eight patients (41 men [46.6%] and 47 women [53.4%]) were assisted. At diagnosis, associated colorectal cancer (CRC) was detected in 53 patients (60.2%), whose average age was higher than those without CRC (40.0 vs. 29.5 years). At colonoscopy, polyposis was classified as attenuated in 12 patients (14.3%). Surgical treatment consisted in total proctocolectomy with ileostomy (PCI, 15 [17.4%]), restorative proctocolectomy (RPC, 27 [31.4%]), total colectomy with ileal-rectum anastomosis (IRA, 42 [48.8%]), palliative segmental resection (1 [1.2%]) and internal bypass (1 [1.2%]). Two patients were not operated on due to religious reasons and advanced disease. Complications occurred in 25 patients (29.0%), more commonly after RPC (48.1%). There was no operative mortality. Local or distant metastases were detected in six (11.3%) patients with CRC treated to cure. During the follow-up of 36 IRA, cancer developed in the rectal cuff in six patients (16.6%), whose average age was higher than in patients without rectal recurrence (45.8 vs. 36.6 years). Five of them have had colonic cancer in the resected specimen. Among the 26 patients followed after RPC, cancer in the ileal pouch developed in 1 (3.8%). Conclusions (1) Within the present series, FAP patients presented a high incidence of associated CRC and diagnosis was generally established after the third decade of life; (2) operative complications occurred in about one third of the patients, being more frequent after the confection of an ileal reservoir; (3) rectal cancer after IRA was detected in 16.6% of patients and it was associated with greater age and previous colonic carcinoma; (4) both continuous and long-term surveillance of the rectal stump and ileal pouch are necessary during follow-up.
Background The role of local excision for pT2 distal rectal cancer has been challenged because of... more Background The role of local excision for pT2 distal rectal cancer has been challenged because of the observation of high rates of lymph node metastases and local failure. However, neoadjuvant chemoradiation therapy (CRT) has led to increased local disease control and significant tumor downstaging, possibly decreasing rates of lymph node metastases. In this setting, a possible role for local excision of ypT2 has been suggested. Methods A total of 401 patients with distal rectal cancer underwent neoadjuvant CRT. Tumor response assessment was performed after at least 8 weeks from CRT completion. One hundred and twelve patients with complete clinical response were not immediately operated on and were excluded from the study, and 289 patients with incomplete clinical response were managed by radical surgery. Patients with final pathological stage ypT2 were analyzed to determine the risk of unfavorable pathological features that could represent unacceptable risk for local failure after local excision. Results Eighty-eight (30%) patients had ypT2 rectal cancer. Final ypT status was not associated with pretreatment radiological staging (p = 0.62). ypT status was significantly associated with the risk of lymph node metastases, risk of perineural and vascular invasion, and recurrence (p = 0.001). Lymph node metastases were present in 19% of patients with ypT2 rectal cancer. The risk of lymph node metastases in ypT2 was associated with the presence of perineural invasion (47% vs 4%; p = <0.001), vascular invasion (59% vs 6%; p < 0.001), and decreased mean interval CRT surgery (12 vs 18 weeks; p < 0.001), but not with mean tumor size (3.2 vs 3.1 cm; p = 0.8). Disease-free and overall survival rates were significantly better for patients with ypT2N0 (p = 0.02 and 0.006, respectively). Fifty-five (63%) patients with ypT2 had at least one unfavorable pathological feature for local excision (lymph node metastases, vascular or perineural invasion, mucinous type or tumor size >3 cm). Conclusion Lymph node metastases were present in 19% of patients with ypT2 and were significantly associated with poor overall and disease-free survival rates. The risk of lymph node metastases could not be predicted by radiological staging or tumor size. Radical surgery should be considered the standard treatment option for ypT2 rectal cancer after CRT.
Objective The objective was to determine the presence and frequency of micrometastasis in lymph n... more Objective The objective was to determine the presence and frequency of micrometastasis in lymph nodes of patients with rectal cancer treated by preoperative chemoradiation followed by curative resection. Patients and methods All 56 patients included were treated with 5-FU and leucovorin plus 5,040 cGy, followed by radical surgery and were diagnosed with stage II distal rectal adenocarcinoma after complete pathological examination (ypT3-4N0M0). Immunohistochemistry was assessed with cytokeratin monoclonal antibody AE1/AE3. Three 4-μm paraffin sections were obtained from each lymph node, cut at 50 μm apart from each other. The results were reviewed by two independent pathologists. Results Mean number of lymph nodes was 9.6 per patient. Four patients (7%) and seven lymph nodes (1.35%) were positive for micrometastasis. Three patients had pT3 and one a pT4 tumor. One of the patients had positive micrometastasis and the presence of mucinous deposits. One other patient had mucinous deposits without any micrometastasis. All four patients are alive with no evidence of recurrent disease. Fourteen patients negative for micrometastasis had recurrent disease (25%), eight systemic (14.7%) and six locoregional (10.3%). There were two cancer-related deaths. The mean follow-up period was 39 months. Conclusion Patients with rectal cancer treated by preoperative chemoradiation showed a surprisingly low rate of micrometastasis detection (7%), even in high-risk patients (T3 and T4 tumors). Lymph node micrometastasis was not associated with decreased overall or disease-free survival. The identification of mucinous deposits on lymph nodes with no viable tumor cells may be direct evidence of lymph node downstaging. The downstaging effect of preoperative chemoradiation therapy may be significant in reducing even micrometastasis detection in low rectal cancer managed by this treatment strategy.
The present study examined the effects of 5-HT 1A and 5-HT 2C receptor agonists on behavioral sat... more The present study examined the effects of 5-HT 1A and 5-HT 2C receptor agonists on behavioral satiety sequence (BSS) in rats. The 5-HT 1A receptor agonist, 8-OH-DPAT (0.5 g), and the 5-HT 2C receptor agonist, Ro-60-0175 (3.0 g), were injected into the paraventricular nucleus (PVN) of rats. The animals were maintained on an ad libitum feeding paradigm with access to water and individual sources of protein, carbohydrate, and fat. Intra-PVN administration of each agonist was associated with decreased carbohydrate consumption. The effect was enhanced by the administration of both agonists together. Behavioral analysis indicated that co-administration of 8-OH-DPAT and Ro-60-0175 interrupted the natural BSS with an increase in non-feeding behavior, whereas the 8-OH-DPAT alone promoted early development of the natural BSS. In conclusion, the 5-HT receptor agonists affected serotonergic modulation of feeding behavior in a functionally selective way.
Aortoenteric fistula is defined as a communication between the aorta and any adjacent segment of ... more Aortoenteric fistula is defined as a communication between the aorta and any adjacent segment of the bowel. It may be primary or secondary. The former occurs de novo in patients with intestinal or vascular diseases, whereas secondary aortoenteric fistula is a rare and dreadful complication of aortic reconstruction with vascular prosthesis. We report a case of a 62-year-old man who presented to the emergency department with acute rectal bleeding. The patient had previous aortoiliac surgery with the utilization of an aorto-bifemoral vascular graft. Diagnosis of secondary aortoenteric fistula was made between the aortoiliac graft and sigmoid colon. After exploratory laparotomy, Hartmann's procedure, excision of the graft, oversewing of the aortic stump, and axilobifemoral bypass were successfully performed. This study reports a rare type of secondary aortoenteric fistula to the left colon, and it describes an unusual and successful surgical treatment. (Curr Surg 62:49-54.
American Journal of Clinical Oncology-cancer Clinical Trials, 2007
Fatigue is a common symptom in cancer patients receiving radiation therapy. We conducted a double... more Fatigue is a common symptom in cancer patients receiving radiation therapy. We conducted a double-blind randomized crossover trial of multivitamins versus placebo in patients with breast cancer undergoing radiation therapy to evaluate fatigue and quality of life. : We randomized 40 patients to either placebo or Centrum Silver. At the middle of the radiation treatments, patients were switched from placebo to multivitamins and vice versa. Patients answered the EORTC QLQ C-30 quality of life (QOL) and Chalder fatigue questionnaires at the beginning, middle, and end of radiation therapy. Both groups experienced decreases in general (P = 0.009; P = 0.001) and physical fatigue scores (P = 0.031; P = 0.029) at the end of the course of placebo compared with the assessment prior to this treatment. We also observed significant improvements in functional (P = 0.026) and symptoms (P = 0.016) score scales of the QOL questionnaire in the patients on placebo. No significant changes were elicited with the use of multivitamins. We also observed significantly lower rates of fatigue in the patients who had just finished a course of placebo as compared with patients finishing a course of multivitamins (0 vs. 25% P = 0.035). Multivitamins do not improve radiation-related fatigue in patients with breast cancer.
Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperi... more Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperiodic critical orbit have intermediate growth. We illustrate some of the difficulties that arise in attacking this conjecture and prove subexponential growth for the iterated monodromy group of $z^2+i$. This is the first non-trivial example supporting the conjecture.
Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperi... more Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperiodic critical orbit have intermediate growth. We illustrate some of the difficulties that arise in attacking this conjecture and prove subexponential growth for the iterated monodromy group of $z^2+i$. This is the first non-trivial example supporting the conjecture.
Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperi... more Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperiodic critical orbit have intermediate growth. We illustrate some of the difficulties that arise in attacking this conjecture and prove subexponential growth for the iterated monodromy group of $z^2+i$. This is the first non-trivial example supporting the conjecture.
Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperi... more Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperiodic critical orbit have intermediate growth. We illustrate some of the difficulties that arise in attacking this conjecture and prove subexponential growth for the iterated monodromy group of $z^2+i$. This is the first non-trivial example supporting the conjecture.
Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperi... more Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperiodic critical orbit have intermediate growth. We illustrate some of the difficulties that arise in attacking this conjecture and prove subexponential growth for the iterated monodromy group of $z^2+i$. This is the first non-trivial example supporting the conjecture.
Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperi... more Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperiodic critical orbit have intermediate growth. We illustrate some of the difficulties that arise in attacking this conjecture and prove subexponential growth for the iterated monodromy group of $z^2+i$. This is the first non-trivial example supporting the conjecture.
Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperi... more Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperiodic critical orbit have intermediate growth. We illustrate some of the difficulties that arise in attacking this conjecture and prove subexponential growth for the iterated monodromy group of $z^2+i$. This is the first non-trivial example supporting the conjecture.
Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperi... more Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperiodic critical orbit have intermediate growth. We illustrate some of the difficulties that arise in attacking this conjecture and prove subexponential growth for the iterated monodromy group of $z^2+i$. This is the first non-trivial example supporting the conjecture.
Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperi... more Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperiodic critical orbit have intermediate growth. We illustrate some of the difficulties that arise in attacking this conjecture and prove subexponential growth for the iterated monodromy group of $z^2+i$. This is the first non-trivial example supporting the conjecture.
Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperi... more Nekrashevych conjectured that the iterated monodromy groups of quadratic polynomials with preperiodic critical orbit have intermediate growth. We illustrate some of the difficulties that arise in attacking this conjecture and prove subexponential growth for the iterated monodromy group of $z^2+i$. This is the first non-trivial example supporting the conjecture.
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Papers by Rodrigo Perez