Perforated peptic ulcer: main factors of morbidity and mortality.

World J Surg. 2003 Jul;27(7):782-7. Perforated peptic ulcer: main factors of morbidity and mortality. Noguiera C, Silva AS, Santos JN, Silva AG, Ferreira J, Matos E, Vilaça H. Surgery Department, Surgery 1, Hospital Geral de Santo António, Instituto de Ciencias Biomédicas Abel Salazar, Largo do Prof. Abel Salazar, 4099-001 Oporto, Portugal. Abstract It is well stated in the literature that medical treatment for peptic ulcer is based on a combination of proton pump inhibitors (PPIs) and antibiotics to eradicate Helicobacter pylori. This treatment is associated with a high rate of immediate success and a low rate of recurrence at 12 months, although it is not effective in all patients. Peptic ulcer (PU) perforation is a serious problem that leads to high complication and mortality rates. Surgical treatment, with its various possibilities, constitutes the ideal treatment. Surgical intervention in these cases, however, can be directed to treating the perforation alone, or it can offer definitive treatment of the ulcer itself. With the hope of establishing why such complications and mortality were seen in the patients in our hospital population, we gathered the facts about PU perforations and the types of surgery performed. We studied 210 consecutive patients (150 men, 60 women) who had undergone surgery at our hospital because of perforation between January 1, 1990 and December 31, 2000. The patients' median age was 53.0 +/- 20.6 years (men 47.7 +/- 17.3 years; women 66.3 +/- 22.0 years). Altogether, 86 patients had significant associated illnesses, 62 were admitted more than 24 hours after the perforation, and 25 were admitted in shock. We performed resections in 10 patients; 88 patients were treated by suturing the perforation with or without a patch of epiploon; and 112 underwent a troncular vagotomy with drainage (VT + Dr). A total of 21 patients died (10%). Significant risk factors that led to complications were identified by statistical studies. They were a perforation that had been present more than 24 hours, the coexistence of significant associated illnesses, and resection surgery. The significant risk factors that led to death were the presence of shock at admission, the coexistence of significant illnesses, and resection surgery. There was no statistically significant difference concerning morbidity and mortality between simple closure of the perforation and definitive surgery (VT + Dr). PMID: 14509505 [PubMed - indexed for MEDLINE

Early gastric cancer: ten years of experience

World J Surg. 2002 Mar;26(3):330-4. Epub 2001 Dec 21. Early gastric cancer: ten years of experience. Nogueira C, Silva AS, Santos JN, Silva AG, Ferreira J, Matos E, Vilaça H. Surgery Department, Surgery 1, Hospital Geral de Santo António, Largo Prof. Abel Salazar, 4000 Oporto, Portugal. [email protected] Abstract Gastric cancer is a disease in which the main treatment is surgical extirpation. The modifications introduced in the surgical treatment over the last decades were accompanied by a clear increase of survival, which reaches global values of 61% at 5 years in Japan. One of the reasons that contribute to this improvement is early diagnosis of the lesions. In the period between January 1, 1990 and December 31, 1999 662 patients with gastric adenocarcinoma were treated in the Service of Surgery 1 of our hospital; 110 were refused surgical treatment. Of the resected patients, 91 (21.4%) were classified as early gastric cancer according to the definition of the Japanese Society of Digestive Endoscopy. There were 30 women and 61 men, with a median age of 60.2 +/- 15 years; 3 patients had a preoperative diagnosis of gastric ulcer; 2 others were operated without recent histology; and 1 patient was urgently resected for a bleeding ulcer. In all the remaining patients biopsy confirmed the presence of cancer (89%) or serious dysplasia (4.6%). The lesions had been distributed essentially in the medium 1/3 (48.3%) and distal 1/3 of the stomach. Subtotal gastrectomy was accomplished in 48 patients, total gastrectomy in 40, total desgastrogastrectomy in 3, and in 9 patients the surgery involved the spleen (8 patients) and the spleen and tail of the pancreas in 1 patient. Lymphadenectomy was not performed in 5 patients, lymph nodes by the first lymph node barrier were removed in 25 patients and by the second barrier in 61 patients (67%). Median tumor size was 26 +/- 1.8 mm. The lesion reached the mucosa in 46 patients and the mucosa and submucosa in 45. In 6 patients the removed lymph nodes were microscopically invaded (6.7%). Five patients died (5.7%). The median follow-up of the patients is 41 +/- 26 months; 7 patients died (8.1%) during this period; 4 died unequivocally of disease progression. The median survival of patients was 85% at 5 years and 80% at 10 years. In our series, survival was affected by the presence of invaded lymph nodes, not by the penetration in depth of the lesion or the size of the tumor. PMID: 11865370 [PubMed - indexed for MEDLINE

Zeolite structures loading with an anticancer compound as drug delivery systems

The authors are thankful to Dr. A. S. Azevedo for collecting the powder diffraction data.Two different structures of zeolites, faujasite (FAU) and Linde type A (LTA), were studied to investigate their suitability for drug delivery systems (DDS). The zeolites in the sodium form (NaY and NaA) were used as hosts for encapsulation of α-cyano-4- hydroxycinnamic acid (CHC). CHC, an experimental anticancer drug, was encapsulated in both zeolites by diffusion in liquid phase. These new drug delivery systems, CHC@zeolite, were characterized by spectroscopic techniques (FTIR, 1H NMR, 13C and 27Al solidstate MAS NMR, and UV−vis), chemical analysis, powder X-ray diffraction (XRD) and scanning electron microscopy (SEM). The effect of the zeolites and CHC@zeolite drug deliveries on HCT-15 human colon carcinoma cell line viability was evaluated. Both zeolites alone revealed no toxicity to HCT-15 cancer cells. Importantly, CHC@zeolite exhibit an inhibition of cell viability up to 585-fold, when compared to the non-encapsulated drug. These results indicate the potential of the zeolites for drug loading and delivery into cancer cells to induce cell deathO.M. and R.A. are recipients of fellowships (SFRH/BD/36463/2007, SFRH/BI/51118/2010) from Fundação para a Ciência e a Tecnologia (FCT, Portugal). This work was supported by the FCT projects refs PEst-C/ QUI/UI0686/2011, PEst-C/CTM/LA0011/2011, and PTDC/ SAU-FCF/104347/2008, under the scope of “Programa Operacional Temático Factores de Competitividade” (COMPETE) of “Quadro Comunitário de Apoio III” and cofinanced by Fundo Comunitário Europeu FEDER, and the Centre of Chemistry and Life and Health Sciences Research Institute (University of Minho, Portugal)

Advances in exosome therapies in ophthalmology–From bench to clinical trial

During the last decade, the fields of advanced and personalized therapeutics have been constantly evolving, utilizing novel techniques such as gene editing and RNA therapeutic approaches. However, the method of delivery and tissue specificity remain the main hurdles of these approaches. Exosomes are natural carriers of functional small RNAs and proteins, representing an area of increasing interest in the field of drug delivery. It has been demonstrated that the exosome cargo, especially miRNAs, is at least partially responsible for the therapeutic effects of exosomes. Exosomes deliver their luminal content to the recipient cells and can be used as vesicles for the therapeutic delivery of RNAs and proteins. Synthetic therapeutic drugs can also be encapsulated into exosomes as they have a hydrophilic core, which makes them suitable to carry water-soluble drugs. In addition, engineered exosomes can display a variety of surface molecules, such as peptides, to target specific cells in tissues. The exosome properties present an added advantage to the targeted delivery of therapeutics, leading to increased efficacy and minimizing the adverse side effects. Furthermore, exosomes are natural nanoparticles found in all cell types and as a result, they do not elicit an immune response when administered. Exosomes have also demonstrated decreased long-term accumulation in tissues and organs and thus carry a low risk of systemic toxicity. This review aims to discuss all the advances in exosome therapies in ophthalmology and to give insight into the challenges that would need to be overcome before exosome therapies can be translated into clinical practice

Model for predicting heat generation and temperature in friction stir welding from the material properties

This paper describes a simple numerical model for predicting the heat generation in friction stir welding (FSW) from the material hot deformation and thermal properties, the process parameters, and the tool and plate dimensions. The model idealises the deformation zone as a two-dimensional axisymmetric problem, but allowance is made for the effect of translation by averaging the three- dimensional temperature distribution around the tool in the real weld. The model successfully predicts the weld temperature field and has been applied with minimal recalibration to aerospace aluminium alloys 2024, 7449 and 6013, which span a wide range of strength. The conditions under the tool are presented as novel maps of flow stress against temperature and strain rate, giving insight into the relationship between material properties and optimum welding conditions. This highlights the need in FSW for experimental high strain rate tests close to the solidus temperature. The model is used to illustrate the optimisation of process conditions such as rotation speed in a given alloy and to demonstrate the sensitivity to key parameters such as contact radius under the shoulder, and the choice of stick or slip conditions. The aim of the model is to provide a predictive capability for FSW temperature fields directly from the material properties and weld conditions, without recourse to complex computational fluid dynamics (CFD) software. This will enable simpler integration with models for prediction of, for example, the weld microstructure and properties

Investigation of exit-hole repairing on dissimilar aluminum-copper friction stir welded joints

Exit-holes in friction stir welded dissimilar aluminum-copper (Al–Cu) joints are repaired by using probeless tools, forcing the surrounding material to fill the exit-hole cavity. The repair by refilling the same base materials is performed in two steps using probeless tools of different diameters. In this study, two different conditions are investigated, keeping the processing parameters constant and varying the tool shoulder diameters. Namely, the repair is performed using a two steps sequence of probeless tools with shoulder diameters of: (1) 12 and 19 mm, and (2) 12 and 27 mm. The refill action is achieved using only the base materials. A comprehensive experimental campaign, including tensile tests, microhardness measurements, scanning electron microscopy and energy dispersive x-ray spectroscopy investigations, have been conducted to evaluate the effectiveness of the repairing. The results showed that the usage of probeless tool is an effective strategy to repair the exit-hole of dissimilar Al–Cu friction stir welds, with exclusive contribution from the same Al and Cu base materials in the cavity of the exit-hole. The original FSW joint with exit-hole, with a diameter of about 8 mm, repaired by shoulder diameters of 12 and 19 mm exhibited ultimate tensile strength about 13% higher than the values provided by the samples taken in the steady-state region of the weld bead The maximum and minimum hardness of the repairing zone made with shoulder diameters of 12 and 19 mm are 240 and 80 HV0.1, respectively, which are within the range of the friction stir welded regions indicated in previous studies