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Organically modified vermiculites were synthesized by previous silylation of three leached vermiculites, V0.3Cl, V0.5Cl and V0.8Cl, under anhydrous conditions following reaction with imidazole (Im), which acted as chelating agent for copper retention. Elemental analysis, X-ray diffraction, infrared spectroscopy, scanning electronic microscopy, transmission electron microscopy, (29)Si and (13)C NMR and nitrogen adsorption/desorption measurements were used to characterize pristine, leached and organofunctionalized solids. X-ray photoelectron spectroscopy (XPS) was used to evaluate the surface after copper sorption. Parameters such as contact time, pH and initial cation concentration for the adsorption of Cu(II) ions were investigated. The adsorption equilibrium data were fitted using the Langmuir isotherm model and the monolayer adsorption capacities were 2.38, 2.52 and 2.69mmolg(-1) for V0.5Cl-Im, V0.3Cl-Im and V0.8Cl-Im, respectively, at pH 6.0 and 298K for a time reaction of 80min. The sorption rates were described by pseudo-second-order kinetics. The chloropropyl imidazole vermiculites are promising adsorbents for the rapid removal of Cu(II) ions from aqueous solution.

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Twenty-seven 7-chloroquinolinotriazole derivatives with different substituents in the triazole moiety were synthesized via copper-catalyzed cycloaddition (CuAAC) click chemistry between 4-azido-7-chloroquinoline and several alkynes. All the synthetic compounds were evaluated for their in vitro activity against Plasmodium falciparum (W2) and cytotoxicity to Hep G2A16 cells. All the products disclosed low cytotoxicity (CC50 > 100 µM) and five of them have shown moderate antimalarial activity (IC50 from 9.6 to 40.9 µM). As chloroquine analogs it was expected that these compounds might inhibit the heme polymerization and SAR studies were performed aiming to explain their antimalarial profile. New structural variations can be designed on the basis of the results obtained.

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Laparoscopic colectomy has developed into a viable alternative to colon surgery. This paper presents an overview of the development and current status of laparoscopic surgery of the colon with a brief review of the evidence of efficacy of laparoscopic surgery in cancer management. The experience with laparoscopic surgery of the colon at a tertiary hospital in Puerto Rico is discussed with review of 142 consecutive cases treated for diverticulosis, cancer or polyps performed from 2005-2010. Data on operative time, technical issues, need for transfusions, specimen size, number of lymph nodes is presented. Data on time to start diet and length of hospital stay are discussed. Surgical complications in the series are discussed in detail and recommendations made on avoidance of technical problems during laparoscopic colon surgery. Recommendations are made on the development and advancement of laparoscopic colonic surgery in Puerto Rico.

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BACKGROUND: Laparoscopic splenectomy has advantages over conventional surgery mainly related to the smaller incision, less postoperative pain and shorter recovery period. The aim of this study was to assess the outcomes of patients with diseases of the spleen managed by elective laparoscopic splenectomy. METHODS: Retrospective review of medical charts was performed of patients who underwent laparoscopic splenectomy by a single surgeon during a three year period. Patient demographics, diagnosis and outcomes including operative time, weight of the specimens, blood loss, operative complications, length of stay, and long term outcome with platelet counts in Immune Thrombocytopenic Purpura (ITP) were reviewed. Data on the presence of an accessory spleens, and need for use of hand assist devices was reviewed. RESULTS: Fourteen patients underwent laparoscopic splenectomy; 9 (nine) for Immune Thrombocytopenic Purpura(ITP); one for Evans Syndrome, one for splenic artery aneurysm, two for suspected lymphoma and one for suspected metastatic disease. Ages were 22 to 70 years (mean 46.6). All patients underwent surgery in a full lateral position. Eight specimens were morcellated for removal and 6 were removed intact; 4 using a hand assist device and two by extending one of the port incisions. In 10 patients, total laparoscopic splenectomy was completed; four patients required use of a hand assist device due to difficulty with the operation. Mean spleen weight was 127 gms; spleen weight for ITP specimens was 90 gms; for non ITP diagnosis mean weight was 230 gms. Accessory spleens were identified and excised in two patients. Mean operative time for all patients was 137 minutes. Mean operative blood loss was 202 ml; no patients were transfused as a result of perioperative bleeding. Time to start diet was from 1-2 days and length of stay was 2.9 days. Two patients had post op fevers requiring prolonged length of stay. There were two readmission for deep venous thrombosis, and one for brain toxoplasmosis six weeks post op. Two ITP patients older than 40 years relapsed during the first year. CONCLUSIONS: Laparoscopic splenectomy can be safely performed using the lateral approach with a high success rate, low rate of blood loss and a low rate of perioperative complications. Laparoscopic splenectomy should be offered to all patients undergoing surgery for ITP. Use of hand assist devices can facilitate surgery for larger spleens and avoid need of conversion to open surgery. Accessory spleens can be adequately identified and excised using laparoscopic splenectomy. Hematologic response in ITP is adequate with laparoscopic splenectomy.

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BACKGROUND: Hand assisted laparoscopic colectomy (HALS) has been shown to have the advantages of laparoscopic colectomy in terms of pain, recovery and length of hospital stay. Studies have shown similar outcomes in laparoscopic colectomy as in open surgery. There is a learning curve to HALS, the operative time is longer, and it is more difficult than open surgery and requires specialized equipment. In this report we present our initial experience over a 2.5 year period using HALS for colon surgery for diverticulosis, polyps and colon cancer. METHODS: A retrospective review of office and hospital charts of patients undergoing HALS colectomy from June 2005 to January 2008 was performed at HIMA-San Pablo Hospital. Demographics, outcomes data including operative time, conversion rate to open surgery, reasons for conversion, time to start feedings, and length of stay were collected as well as staging and number of nodes for cancer patients. Complications are discussed along with comments pertinent to the experience of two surgeons going through the learning curves of LC and HALS colectomy. RESULTS: A total of 65 patients underwent attempted hand assisted laparoscopic colon resection. There were 33 males and 32 females between the ages of 26 and 87. Thirty-one patients underwent surgery for diverticulosis; 8 for pre-malignant lesions (large polyps or polyps with high grade dysplasia), and 26 for colon cancer. Mean operative time was 195 minutes (120 to 300); mean length of stay was six days (range 4-14 days). Conversion rate was (13.8%) overall; 21% during the first year and 10.8% after the first year. 5 (7.5%) of the patients in which HALS colon resection was completed had complications with prolonged length of stay. Patients without complication had an average length of stay of 4.5 days. The average number of lymph nodes was 14.8 (range 7-24); average length of specimens for diverticulosis was 17cm. Complications included postoperative bleeding in three patients who required early reoperation, prolonged ileus and small bowel obstruction in two patients. One patient developed a pelvic collection requiring a drain, and one patient had a wound infection requiring re-admission and antibiotics. No patient required colostomy due to a complication. There were no operative deaths. CONCLUSION: HALS colectomy is a safe and feasible alternative to open colectomy in a community hospital setting with proper expertise and equipment. Patients will benefit from faster recovery time and decreased length of stay in the hospital. Oncologic results are similar to open surgery. Operative times are longer than with open surgery and the operations are difficult to learn and master.

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BACKGROUND/OBJECTIVE: An extensive web search failed to provide studies from Puerto Rico regarding whether open (OA) or laparoscopic appendectomy (LA) should be performed for non-complicated appendicitis. Our goal is to compare these techniques in terms of time at operating room (OR), length of surgery, hospital stay, pain medication requirements, in-hospital complications and readmissions. METHODS: 126 patients (64 OA; 62 LA) with non-complicated appendicitis were studied retrospectively. Data obtained: demographics, CT-Scan use, surgery and operating room time, days in hospital, complications, diet commencement, pain medications doses, pathology and readmission. RESULTS: Difference was found in total time at OR (80.1+/-29 minutes OA; 105.7+/-22.6 LA) and in surgery length (41+/-28 OA; 48+/-16 LA), but not in hospital stay (2.1 days OA; 2.2 LA) nor in in-hospital complication rate. Negative appendectomy rate was 24% LA vs. 3% OA. Readmission rate was higher in OA with 5% wound infection rate. CONCLUSION: Techniques are similar in mean hospital stay, in-hospital complications, and pain medication requirements. LA had a higher negative appendectomy rate but of these patients five had surgical diagnosis of acute appendicitis and after appendectomy, signs and symptoms resolved; and two patients had interval appendectomies. As these patients were cured, the real negative appendectomy rate is 13%, similar to the historically accepted 16%. The other eight patients had an adequate diagnosis. We are concerned OA negative appendectomy rate is only 3%; we wonder if surgeons are waiting too long to operate patients. Readmission was higher in OA (wound infection rate of 5%). Although it takes more time in the OR, LA is as safe as OA, has a low rate of complications and lower readmission rate.

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The Society of Toxicologic Pathology (STP) has developed the following recommendations for the use of pathology images in compliance with the Code of Federal Regulations (CFR), Volume 21, Part 58 (Good Laboratory Practices [GLP]) and Part 11 (Electronic Records/Signatures). These recommendations include: (1) based on current technologies and practices, pathology images (printed, electronic, or digital) used for data generation (e.g., to make a diagnosis or for morphometric analysis) are raw data that must be authenticated and archived; (2) authentication of an image may be done either by initialing and dating a print of the image or by specifically annotating the electronic image file in compliance with Part 11 regulations; (3) images used for raw data are subject to GLP procedures and controls in order to ensure data integrity including written Standard Operating Procedures, testing/validation of equipment, training of personnel, etc.; (4) validation and/or performance qualification of imaging systems used to support GLP studies must be documented and any exceptions to full validation/qualification must be described in the GLP Compliance Statement for the study; (5) images that are not used for data generation are illustrative images, are not raw data, and generally do not have to be archived; 6) illustrative images should not be used to re-evaluate or supersede the pathologist's diagnosis.

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We designed a single-chain variant of the Arc repressor homodimer in which the beta strands that contact operator DNA are connected by a hairpin turn and the alpha helices that form the tetrahelical scaffold of the dimer are attached by a short linker. The designed protein represents a noncyclic permutation of secondary structural elements in another single-chain Arc molecule (Arc-L1-Arc), in which the two subunits are fused by a single linker. The permuted protein binds operator DNA with nanomolar affinity, refolds on the sub-millisecond time scale, and is as stable as Arc-L1-Arc. The crystal structure of the permuted protein reveals an essentially wild-type fold, demonstrating that crucial folding information is not encoded in the wild-type order of secondary structure. Noncyclic rearrangement of secondary structure may allow grouping of critical active-site residues in other proteins and could be a useful tool for protein design and minimization.

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In some patients exercise induces numerous complaints which cannot be attributed to an organic disorder, and which are suggestive of hyperventilation. The study was designed to investigate in this type of patient: 1) exercise capacity and muscle force; 2) breathing pattern and symptoms during maximal exercise and recovery; 3) relationships between symptoms and breathing pattern. Twenty-four patients were compared with 20 healthy subjects. They performed a maximal incremental cycle ergometer test and peripheral and respiratory muscle strength were measured. Patients tended to have a decreased exercise capacity and presented with moderately reduced muscle strength. At comparable minute ventilation, breathing frequency was higher (mean: 24 versus 21 per minute) and tidal volume smaller (mean: 1.42 versus 1.67 L). End-tidal partial pressure of carbon dioxide (PET,CO2) was not significantly different. A significant relation was observed between PET,CO2 and respiratory frequency during recovery in patients, suggesting a reduced flexibility of the ventilatory response to exercise. In patients respiratory complaints and paresthesias were weakly correlated to PET,CO2 at moderate exercise. It is suggested that the physical deconditioning observed in those patients is rather a consequence than a cause of the response to exercise. The link between symptoms and breathing pattern might be explained by a psychological conditioning process.

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