Temperature phased anaerobic digestion (TPAD) of organic fraction of municipal solid waste (OFMSW) and digested sludge (DS): Effect of different hydrolysis conditions.

Hydrolysis is the most critical stage in high solids Temperature Phased Anaerobic Digestion (TPAD). In this paper two different Organic Fraction of Municipal Solid Waste (OFMSW) types were tested in co-digestion with Digested Sludge (DS) at different temperatures: 37, 55 and 65 °C. Volatile fatty acids (VFAs), soluble chemical oxygen demand (CODs) and Biochemical Methane Production (BMP) were measured and calculated after 0, 24, 48 and 72 h hydrolysis. The results showed that both the BMP and the methane production rate improved. A Solids Retention Time (SRT) of 72 h at a temperature of 55 °C gave the best results: the reaction rate constant k was 0.34 d-1 and the BMP was 250 mLCH4/gMV, which were 47% and 19% higher compared to the reference (0 h hydrolysis). The CODs and VFAs profiles during hydrolysis showed how OFMSW initial characteristics can affect the performance of temperature phased anaerobic digestion.

Environmental factors influencing landfill gas biofiltration: Lab scale study on methanotrophic bacteria growth.

The post-management of landfills represents an important challenge for landfill gas treatment. Traditional systems (energy recovery, flares, etc.) present technical problems in treating flow with low methane (CH4) concentrations. The objective of this study was to isolate methanotrophic bacteria from a field-scale biofilter in order to study the bacteria in laboratories and evaluate the environmental factors that mostly influence Microbial Aerobic Methane Oxidation (MAMO). The soil considered was sampled from the biofilter located in the landfill of Venosa (Basilicata Region, Italy) and it was mainly composed of wood chips and compost. The results showed that methanotrophic microorganisms are mainly characterized by a slow growth and a significant sensitivity to CH4 levels. Temperature and nitrogen (N) also have a very important role on their development. On the basis of the results, biofilters for biological CH4 oxidation can be considered a viable alternative to mitigate CH4 emissions from landfills.

Physiopathology and clinical considerations of laparoscopic surgery in the elderly.

OBJECTIVE: The marked improvements in medical technology and healthcare, lead an increasing number of elderly patients to take advantage of even complex surgical. Recently, laparoscopic surgery has been accepted as a minimally invasive treatment to reduce the morbidity after conventional surgery, and a number of studies have demonstrated the feasibility of laparoscopy with significant advantages also in the elderly. On the other side, the laparoscopic procedure has some drawbacks, including prolonged operation time and impact of carbon dioxide pneumoperitoneum on circulatory and respiratory dynamics. This paper will review the physiopathological implications of laparoscopy, as well as the current literature concerning the most common laparoscopic procedures that are increasingly performed in elderly patients. MATERIALS AND METHODS: A systematic review of the current literature was performed using the search engines EMBASE and PubMed to identify all studies reporting the physiopathological implications of laparoscopy in the elderly. The MeSH search terms used were "laparoscopy in the elderly", "physiopathology of laparoscopy", and "pneumoperitoneum". Multiple combinations of the keywords and MeSH terms were used with particular reference to elderly patients. RESULTS: Although laparoscopy is minimally invasive in its dissection techniques, the increased physiologic demands present particular challenges among elderly patients. CONCLUSIONS: Laparoscopy and its safety in the elderly patients remains a challenge and the evaluation of this approach is therefore mandatory. Although many studies have demonstrated the applicability and advantages of the laparoscopy also in the geriatric population, with low rates of morbidity and mortality, in elderly patients undergoing general surgical procedures the physiologic demands of laparoscopy should be carefully considered.

Methane oxidation in a biofilter (Part 2): A lab-scale experiment for model calibration.

In this study an experimental study on a biological methane oxidation column presented with the aim to calibrate a mathematical model developed in an earlier study. The column was designed to reproduce at lab-scale a real biofilter trying to consider the more probable landfill boundary conditions. Although the methane oxidation efficiency in the column was lower than the expected (around 35%), an appropriate model implementation showed an acceptable agreement between the outcomes data of the model simulation and the experimental data (with Theil's Inequality Coefficient value of 0.08). A calibrated model allows a better management of the biofilter performance in terms of methane oxidation.

Methane oxidation in a biofilter (Part 1): Development of a mathematical model for designing and optimization.

The aim of this work is the evaluation of the efficiency of such a biofilter, through the application of a mathematical model which describes the biological oxidation process. This mathematical model is able to predict the efficiency of the system under varying operating conditions. Literature data have been used in order to build the model. The factors that mostly affect the process and which actually regulate the entire process have been highlighted in this work. Specifically, it was found that temperature, flow and methane concentration are the most important parameters that influence the system. The results obtained from the mathematical model showed also that the biofilter system is simple to implement and manage and allows the achievement of high efficiency of methane oxidation. In the optimal conditions for temperature (between 20-30°C), residence time (between 0.7-0.8 h) and methane molar fraction (between 20-25%) the efficiency of methane oxidation could be around 50%.

Cystic pancreatic neuroendocrine tumors: To date a diagnostic challenge.

OBJECTIVE: Cystic PNETs are an uncommon neoplasms increasingly detected in current clinical practice which often present a diagnostic challenges to both the experienced radiologist and pathologist. The aim of this study was to review the available literature to summarize current data that compare and evaluate both the clinical and pathologic features of cystic pancreatic neuroendocrine tumors. MATERIALS AND METHODS: A systematic review of the current literature was performed using the search engines EMBASE and PubMed to identify all studies reporting on cystic pancreatic neuroendocrine tumors. The MeSH search terms used were "cystic pancreatic neuroendocrine tumors", "endocrine neoplasms", and "pancreatic cysts". Multiple combinations of the keywords and MeSH terms were used. RESULTS: The clinical evaluation of cystic pancreatic lesions appears to suffer from same limitations despite the improvement in the diagnostic tools. Subsequently, we highlight diagnostic pitfalls and differential diagnosis of these cystic tumors. In this review we discuss current advances in the application of the imaging modalities and characteristics features with special emphasize on endoscopic ultrasound (EUS), and EUS guide fine needle aspiration (EUS-FNA). CONCLUSIONS: Cystic neuroendocrine tumor in the pancreas underlines the clinical impact of endoscopic ultrasound in the work-up of patients with unclear lesions in the pancreas. EUS-FNA cytology and cyst fluid analysis is a useful adjunct to abdominal imaging for the diagnosis of pancreatic cystic lesions. Due to the evident diagnostic difficulties, we hypothesize that cyst fluid characteristics, including cytomorphological features, is the most accurate test to achieve a preoperative diagnosis and to provide a basis for prognostic prediction.

Laparoscopic cholecystectomy and concomitant diseases Effectiveness of the single step treatment.

AIM: With the expanded use of laparoscopy, the options for combined surgical procedures have also increased and can be a modality of choice for coexisting pathologies in the abdomen. In our study we evaluate the safety and the efficacy of a number of surgical procedures combined with laparoscopic cholecystectomy and report our results. MATERIAL OF STUDY: We conducted a retrospective study on 19 consecutive patients who underwent laparoscopic cholecystectomy simultaneously with other operations. RESULTS: No conversion to open surgery was necessary. Postoperative complications occurred in three patients. The mean postoperative hospital stay was 3 days (range 2-4) and a few patients required more than 48 hours postoperative hospitalization. The perioperative mortality rate was 0%. DISCUSSION: Concomitant surgical procedures result in longer operating time, but certainly the patient benefits from a single exposure to anesthesia, single hospital stay, and single period of absence from work. CONCLUSIONS: Combining surgeries does not significantly alter the outcome of the procedure, proved to be a safe and feasible and present an interesting alternative to two separate operations. Prospective studies with long-term follow-up are required to better understand the implications of simultaneous operations. KEY WORDS: Laparoscopic combined procedures, Minimally invasive surgery.

Incisional hernia in the elderly: risk factors and clinical considerations.

OBJECTIVE: Ventral incisional hernia is a common complication of abdominal surgery. The marked improvements in medical technology and healthcare, lead to an increasing number of elderly patients to take advantage of even complex surgical procedures. The objective of this literature review was to analyze the risk factors for ventral incisional hernia in elderly patients and to identify measures that might decrease the incidence of this complication. MATERIALS AND METHODS: An analysis of the surgical literature was performed using the search engines EMBASE, Cochrane Library, and PubMed with particular reference to elderly patients using the keywords: abdominal hernia, wound dehiscence, incisional hernia, incidence, trocar site hernia, and hernia prevention. RESULTS: In our opinion the risk factors for incisional hernia should be separately considered. First those related to the patients and to the abdominal surgery and, in addition, those related to the surgery of the abdominal wall defects. CONCLUSIONS: Reparative surgery of the abdominal wall, to date uniquely characterized by the use of the mesh, should be considered an additional risk factor for the occurrence of incisional hernia. However, the low incarceration risk, the risk of recurrence, the relevant rate of postoperative pain and discomfort and complications associated with mesh repair, as small bowel obstruction, mesh infection, and entero-cutaneous fistula, suggest that the general indication for surgical treatment of incisional hernias, in a symptomatic or oligosymptomatic elderly patients, should be critically reconsidered in order to avoid unnecessary surgery.

Appendix stump closure with endoloop in laparoscopic appendectomy.

AIM: To address the question of the appendix stump closure in laparoscopic appendectomy and evaluate the incidence of intraoperative and postoperative complications after application of endoloops. MATERIAL OF STUDY: Data included age and gender, ASA score, co-morbid illness, prior abdominal surgery, clinical presentation, operative time, conversion rate and reasons for conversion, postoperative morbidity and mortality rates, pathologic diagnosis, and length of hospital stay. RESULTS: Laparoscopic appendectomy with stump closure using endoloops was performed in 35 consecutive patients. Postoperative complications occurred in three patients. The mean postoperative hospital stay was 2 days. The perioperative mortality rate was 0%. DISCUSSION: The treatment of appendiceal stump closure in laparoscopic appendectomy represents the main technical aspect and it is an important step for its potentially serious postoperative complications due from an inappropriate management. Endostapling, hem-o-lok clips and intracorporeal knotting are the most commonly recommended methods. All alternatives have advantages and disadvantages against the different clinical stages of acute appendicitis, and it should be noted that the different forms of appendiceal stump closure have never been assessed in prospective randomized studies. CONCLUSIONS: From our experience we can confirm that the endoloop can be safely used and should be the preferred modality in treating the appendiceal stump, especially for low-grade appendicitis. Alternative methods should be used in case of phlegmonous or gangrenous appendicitis, perityphlitic abscess or simultaneous operation for Meckel's diverticulum. Knowledge about and appropriate use of all of them are important for a safe and more cost-effective procedure. KEY WORDS: Appendiceal stump closure, Laparoscopic appendectomy.

Post-orchidectomy retroperitoneal seminoma: A case report.

Between 2 and 5% of malignant germ cell tumors in males arise at extragonadal sites. The origin of extragonadal retroperitoneal germ cell tumors remains controversial. Whether these develop primarily in the retroperitoneum or are metastases of a primary testicular tumor has long been debated. We report a 38-year-old male who presented with abdominal pain and was diagnosed with retroperitoneal seminoma. The patient gave a history of having undergone a right orchidectomy for an undescended testis via the inguinal route 10 years previously with a reported histology of benign inflammatory mass.

Can laparoscopic cholecystectomy be safety performed in the elderly?

AIM: To assess the suitability of laparoscopic cholecystectomy in elderly patients, although early reports have questioned the efficacy of this procedure in that patient group. MATERIAL OF STUDY: Retrospective study evaluating the medical records of the elderly patients who underwent laparoscopic cholecystectomy in our surgical unit. Data included age and gender, American Society of Anesthesiologists (ASA) score, comorbid illness, prior abdominal surgery, presentation, operative time, conversion rate, postoperative morbidity, and mortality rates and length of hospital stay. RESULTS: Fifty consecutive patients age 70 or older who underwent laparoscopic cholecystectomy were studied Postoperative complications occurred in five patients. DISCUSSION: Many Studies have shown that the incidence of complicated gallstone disease in the elderly is higher when compared with that of younger patients and gallbladder disease is particularly virulent in the elderly, with high rate of acute cholecystitis, biliary tract disease, increased morbidity, and prolonged hospital stay. This poor outcome has been attributed to the presence of severe co-morbid factors associated with the aging process. Compared to open cholecystectomy, laparoscopic cholecystectomy may cause less postoperative depression of respiratory function and cell-mediated immunity. In our study perioperative mortality rate was 0%. CONCLUSIONS: Laparoscopic cholecystectomy in elderly patients is a relatively safe procedure that can be accomplished with acceptable low morbidity. In this series of geriatric patients, there was no evidence of any increased risk for conversion to an open cholecystectomy, delayed recovery, or prolonged hospitalization.

Could a high resectability rate improve the long-term survival of patients with proximal bile duct cancer?

BACKGROUND AND OBJECTIVES: This retrospective study was undertaken to evaluate if high resectability rate could improve the long-term outcome of patients with proximal bile duct cancer. METHODS: Between 1985 and 2001, 50 patients (34 male and 16 female) with proximal bile duct cancer were treated. Thirty-six patients (72%) were considered suitable for surgery, while 14 underwent nonsurgical palliative procedures. Twenty patients had bile duct resection only. Ten patients had Roux-en-Y cholangiojejunostomy with two or three divided segmental hepatic ducts; in 10 patients, the cholangiojejunostomy was performed with four or five divided segmental hepatic ducts. Three patients were treated by palliative transtumoral intubation with Kehr tube. Thirteen patients had bile duct resection plus hepatectomy. Despite the curative intention of the operation, only in 19 (52.7%) patients did the histopathological examination reveal tumor-free margins. RESULTS: There was no operative mortality. Postoperative morbidity was 25%. Overall 1-, 3-, and 5-year survival of the entire surgical group was 61%, 22.5%, and 9%, respectively. In the 19 patients treated with curative intent the survival at 1, 3, and 5 years was 63.1%, 31.5%, and 15.8%, respectively, while in the group that had palliative treatment it was 45%, 15%, and 0%, respectively. CONCLUSIONS: Only margins free from tumor can guarantee an improvement in long-term outcome. Increasing resectability improves survival and could offer a chance of better long-term survival.

[Laparoscopic treatment of benign ovarian cysts]. / Trattamento laparoscopico della patologia ovarica cistica benigna.

Laparoscopic surgery is the most frequent indication for the management of benign ovarian cysts in the obstetric and gynaecological field. On the basis of their experience the authors address the clinical classification of benign ovarian pathology and the surgical laparoscopic procedures utilised in the treatment of adnexal cysts. Forty-two patients underwent laparoscopic surgery after a preoperative clinical and biological evaluation and imaging in order to exclude the presence of ovarian malignancies. All surgical procedures were carried out laparoscopically, with a conversion index of 0%. The morbidity was 2.3% (one case of haematoma of the umbilical trocar site) and there was no mortality. No late complications were observed. In conclusion, laparoscopic surgery in the management of ovarian cysts is technically feasible. On the basis of these findings laparoscopic surgery is the treatment of choice for adnexal cystic tumours after careful exclusion of malignancy.

Poorly differentiated jejunal adenocarcinoma in a patient with coeliac disease: a case report.

It is well known that coeliac disease increases the risk of gastrointestinal lymphomas, whereas adenocarcinoma is a rare complication. The authors report a case of a poorly differentiated jejunal adenocarcinoma complicating coeliac disease in a 40-year-old female and discuss the clinical, diagnostic and therapeutic aspects.

[Role of nutritional support in the treatment of enteric fistulas]. / Ruolo del trattamento nutrizionale nelle fistole enteriche.

Enteric fistulas are nowadays considered an important therapeutic challenge. Artificial, total parenteral and enteral nutrition have allowed an improvement in the healing of these fistulas and a lower incidence of mortality. Fourteen patients with enteric fistulas (10 men, 4 women; mean age: 64.4 years; range: 20-80 years) were observed. The fistula was located in the large bowel in 11 patients, in the ileum in 2, and in the jejunum in 1. Thirteen patients received enteral nutrition. The patient with the jejunal fistula received total parenteral nutrition for 30 days and then enteral nutrition. The fistulas were successfully treated in 11 patients. One patients underwent surgery after 6 weeks of treatment with enteral nutrition because of lack of improvement of the symptomatology. In two patients, with advanced cancer of the colon and stomach, respectively, only a reduction of the fistula output was achieved. Nutritional support in the treatment of enteric fistulas is an effective procedure widely utilised to restore adequate nutritional status and bowel rest, which are two important targets for achieving fistula closure. Nutritional support is also useful in the management of patients undergoing surgery in order to reduce the postoperative complication rate.

[Robotic techniques in laparoscopic surgery]. / La robotica in chirurgia laparoscopica.

Robotic technology is being increasingly used in surgery. The authors assess the usefulness, effectiveness and safety of the AESOP 2000 robotic device (Automated Endoscopic System for Optimal Positioning) in videolaparoscopic surgery. Two laparoscopic cholecystectomies were performed with the aid of the AESOP 2000 robot. A short increase in operative time was observed and there were no complications. Voice understanding was accurate and flawless and no inadvertent smearing of the lens occurred. The use of the AESOP 2000 robotic device is safe, improves the quality of vision and reduces the number of surgeons needed in the team. Nevertheless, a learning curve and simultaneous training in the use of the device are required.

[Laparoscopic treatment in a case of torsion of ovarian benign mature teratoma. Clinical case and review of the literature]. / Trattamento laparoscopico in un caso di torsione di teratoma maturo benigno dell'ovaio. Caso clinico e revisione della letteratura.

Benign mature teratomas account for approximately 10-17% of all ovarian neoplasms and are the type of ovarian neoplasm most likely to occur during a woman's reproductive life. Bilateral localization is observed in some 10-15% of cases and the estimated incidence of malignant degeneration is 0.5-1.8%. The authors report a case of a 35-year-old woman admitted with discontinuous abdominal and pelvic pain. Imaging procedures showed an adnexal mass with the appearance of a dermoid cyst. The patient underwent laparoscopic ovarian cystectomy with preservation of the adnexal gland. After a review of the international literature and a description of the clinical features of the disease the authors go on to stress the advantages of laparoscopic management of benign ovarian teratomas.

Locally advanced breast cancer in the elderly: a major challenge requiring effective and appropriate treatment.

AIMS AND BACKGROUND: Breast cancer is the most common tumor in women. As the population above 65 years increases, breast cancer will be a more substantial problem for elderly patients. This work reports our experience in the management of stage III and IV locally advanced breast cancer. METHODS: Nineteen patients over 65 years of age (mean, 70.3 years) with stage III and IV breast cancers, treated between 1990 and 2000, are considered. The management and outcome are evaluated. RESULTS: Nine patients had stage IIIA breast cancer, 7 stage IIIB and 3 stage IV. Sixteen underwent Madden mastectomy and 3 simple mastectomy. Patients at stage IIIB and 1 patient at stage IV with T4 tumor received neo-adjuvant chemotherapy. There were no significant postoperative complications. Sixteen patients were given tamoxifen and 10 patients adjuvant chemotherapy. Patients were followed for a median of 36.7 months (range, 6-72 months). In 8 patients with stage IlIl disease, metastasis developed. Two patients had local recurrence of disease. Of the patients at stage IIIA, 6 were free from disease (one died from unrelated causes) and 3 had recurrent disease (2 died). Of the patients at stage IIIB, 2 are disease free and 5 had recurrent disease and died. Of the patients at stage IV, only one is alive. CONCLUSIONS: Stage and individual characteristics of elderly women influence management. Patients should be managed adequately since most of them are fit enough to undergo treatment.