Leandro Ryuchi Iuamoto

Human islet xenotransplantation in rodents: A literature review of experimental model trends

Among the innovations for the treatment of type 1 diabetes, islet transplantation is a less invasive method of treatment, although it is still in development. One of the greatest barriers to this technique is the low number of pancreas donors and the low number of pancreases that are available for transplantation. Rodent models have been chosen in most studies of islet rejection and type 1 diabetes prevention to evaluate the quality and function of isolated human islets and to identify alternative solutions to the problem of islet scarcity. The purpose of this study is to conduct a review of islet xenotransplantation experiments from humans to rodents, to organize and analyze the parameters of these experiments, to describe trends in experimental modeling and to assess the viability of this procedure. In this study, we reviewed recently published research regarding islet xenotransplantation from humans to rodents, and we summarized the findings and organized the relevant data. The included studies were recent reports that involved xenotransplantation using human islets in a rodent model. We excluded the studies that related to isotransplantation, autotransplantation and allotransplantation. A total of 34 studies that related to xenotransplantation were selected for review based on their relevance and current data. Advances in the use of different graft sites may overcome autoimmunity and rejection after transplantation, which may solve the problem of the scarcity of islet donors in patients with type 1 diabetes.

Stents for Bronchial Stenosis After Lung Transplantation: Should They Be Removed?

BACKGROUND Airway complications after lung transplantation are the major cause of morbidity, affecting up to 33% of all cases. Bronchial stenosis is the most common complication. The use of stents has been established as the most effective therapy; however, their removal is recommended after 3-6 months of use. We have been using self-expandable stents as a definitive treatment and remove them only if necessary. For this report, we evaluated the use of self-expandable stents as a definitive treatment for bronchial stenosis after lung transplantation. METHODS We performed a retrospective cohort study to evaluate patients with bronchial stenosis from August 2003 to April 2014. Clinical and pulmonary function test data were collected. RESULTS Two hundred lung transplants were performed, 156 of which were bilateral. Sixteen patients experienced airway complications: 4 had dehiscence, 2 necrosis, and 10 bronchial stenosis. Of these patients, 7 had undergone bilateral procedures, and 2 patients developed stenosis in both sides. Twelve anastomotic stenoses were observed. The follow-up after stenting ranged from 1 to 7 years. All patients had increased lung function, and 4 remained stable with sustained increase in pulmonary function without episodes of infection. Three patients required removal of their prosthesis 6 months to 1 year after implantation because of complications. Two patients died owing to unrelated causes. CONCLUSIONS Definitive treatment of bronchial stenosis with self-expandable stents is a viable option. The 1st year seems to be the most crucial for determining definitive treatment, because no patients required removal of their stent after 1 year.

Perioperative management of drugs commonly used in patients with rheumatic diseases: a review

Rheumatic diseases are very prevalent, affecting about 7 million people in North America; they affect the musculoskeletal system, often with systemic involvement and potential for serious consequences and limitation on quality of life. Clinical treatment is usually long-term and includes drugs that are considered either simple or complex and are occasionally unknown to many health professionals who do not know how to manage these patients in emergency units and surgical wards. Thus, it is important for clinicians, surgeons and anesthesiologists who are involved with rheumatic patients undergoing surgery to know the basic principles of therapy and perioperative management. This study aims to do a review of the perioperative management of the most commonly used drugs in rheumatologic patients. Manuscripts used in this review were identified by surveying MEDLINE, LILACS, EMBASE, and COCHRANE databases and included studies containing i) the perioperative management of commonly used drugs in patients with rheumatic diseases: and ii) rheumatic diseases. They are didactically discussed according to the mechanism of action and pharmacokinetics; and perioperative management. In total, 259 articles related to the topic were identified. Every medical professional should be aware of the types of drugs that are appropriate for continuous use and should know the various effects of these drugs before indicating surgery or assisting a rheumatic patient postoperatively. This information could prevent possible complications that could affect a wide range of patients.

Large primary hepatic gastrinoma in young patient treated with trisegmentectomy: A case report and review of the literature

Primary hepatic gastrinoma is a rare disease, with fewer than 40 cases reported in the medical literature. Because it is located in an organ in which metastases are common, its diagnosis is difficult. We report a case of a 19 years old male patient with a history of gastric ulcers since the age of nine. Following gastric surgery, an antrectomy and a vagotomy, there was some alleviation of symptoms. Subsequently, the patient reported various intermittent episodes of diarrhea, diffuse abdominal pain, and vomiting. The patient underwent tomography, which revealed the presence of a hepatic mass measuring 19.5 cm × 12.5 cm × 17 cm. Primary hepatic gastrinoma was diagnosed based on laboratory examinations that indicated hypergastrinemia and a positron emission tomography/magnetic resonance study with somatostatin analogue that confirmed the liver as the primary site. After hepatic trisegmentectomy (II, III, IV, V, VIII), the patient’s symptoms improved. The case is notable for the presence of a rare tumor with uncommon dimensions.

Burkholderia cepacia, cystic fibrosis and outcomes following lung transplantation: experiences from a single center in Brazil

OBJECTIVES: To evaluate the impact of Burkholderia cepacia complex colonization in cystic fibrosis patients undergoing lung transplantation. METHODS: We prospectively analyzed clinical data and respiratory tract samples (sputum and bronchoalveolar lavage) collected from suppurative lung disease patients between January 2008 and November 2013. We also subtyped different Burkholderia cepacia complex genotypes via DNA sequencing using primers against the recA gene in samples collected between January 2012 and November 2013. RESULTS: From 2008 to 2013, 34 lung transplants were performed on cystic fibrosis patients at our center. Burkholderia cepacia complex was detected in 13 of the 34 (38.2%) patients. Seven of the 13 (53%) strains were subjected to genotype analysis, from which three strains of B. metallica and four strains of B. cenocepacia were identified. The mortality rate was 1/13 (7.6%), and this death was not related to B. cepacia infection. CONCLUSION: The results of our study suggest that colonization by B. cepacia complex and even B. cenocepacia in patients with cystic fibrosis should not be considered an absolute contraindication to lung transplantation in Brazilian centers.

Gastric fundus submucosa as a site for islets transplantation: An experimental study

Background Islets of Langerhans transplantation is a promising alternative for glycemic control in patients with type 1 diabetes. The graft site is a factor that has large impact on the functioning of this transplant, and the stomach appears to be a promising location. Our objective is to describe a new experimental model for the grafting of Islets of Langerhans in rat stomachs. Methodology Islets of Langerhans were extracted from 45 isogenic male rats of the Lewis lineage and transplanted into 9 isogenic rats of the Wistar lineage; 5 in the gastric body submucosa, and 4 in the gastric fundus submucosa. Normoglycemia was defined as two successive measurements of <250 mg/dL. No immunosuppression was used. The two groups glycemia control improvement were compared with t-student test. Results The results obtained following the transplantation of the islets in 9 rats showed between 995 and 2310 islets transplanted (mean of 1367). The rats from the gastric submucosa group had a better glycemic level improvement, with a confidence equal to 83.94%. Conclusion Islets graft into the gastric fundus submucosa is a viable model with potential for adequate glycemic control. This model gives potential for new perspectives and future studies in this area.

Component separation of abdominal wall with intraoperative botulinum A presents satisfactory outcomes in large incisional hernias: a case report

Highlights • Transplantation patients presents associated risk factors that make appearance of incisional hernia more likely.• Several aspects of the closure of large hernia defects following liver transplatation remain controversial.• A successful approach for selected patient group for whom there is no established standard treatment is described.

IMPACT OF OBESITY AND SURGICAL SKILLS IN LAPAROSCOPIC TOTALLY EXTRAPERITONEAL HERNIOPLASTY

ABSTRACT Background: Laparoscopic totally extraperitoneal (TEP) hernia repair is a technically demanding procedure. Recent studies have identified BMI as an independent factor for technical difficulty in the learning period. Aim: To analyze the effect of overweight and obesity on the technical difficulties of TEP. Method: Prospective study on patients who underwent a symptomatic inguinal hernia by means of the TEP technique. Were analyzed gender, BMI, previous surgery, hernia type, operative time and complications. Technical difficulty was defined by operative time, major complications and recurrence. Patients were classified into four groups: 1) underweight, if less than 18,5 kg/m²; 2) normal range if BMI between 18,5 and 24,9 kg/m²; 3) overweight if BMI between 25-29,9 kg/m²; and 4) obese if BMI≥30 kg/m². Results: The cohort had a total of 190 patients, 185 men and 5 women. BMI values ranged from 16-36 kg/m² (average 26 kg/m²). Average operating time was 55.4 min in bilateral hernia (15-150) and 37.8 min in unilateral (13-150). Time of surgery was statistically correlated with increased BMI in the first 93 patients (p=0.049). Conclusion: High BMI and prolonged operative time are undoubtedly correlated. However, this relationship may be statistically significant only in the learning period. Although several clinical features can influence surgical time, upon reaching an experienced level, surgeons appear to easily handle the challenges.

A simple technique can reduce cardiopulmonary bypass use during lung transplantation

Cardiopulmonary bypass causes an inflammatory response and consumption of coagulation factors, increasing the risk of bleeding and neurological and renal complications. Its use during lung transplantation may be due to pulmonary hypertension or associated cardiac defects or just for better exposure of the pulmonary hilum. We describe a simple technique, or open pericardium retraction, to improve hilar exposure by lifting the heart by upward retraction of the pericardial sac. This technique permits lung transplantation without cardiopulmonary bypass when bypass use is recommended only for better exposure.