Raman-assisted crystallography applied to protein metalation

This doctoral project explores different aspects of the interaction between Au nanoparticles, Hg, Ir, and Ru-based compounds with proteins, as well as, in a reversed perspective, the interaction of the ligand with metal‑containing proteins. These issues are addressed by means of the novel yet spreading approach, the Raman‑assisted crystallography (RAC), which joints strengths to override curbs from either the two techniques it relies on

Surgical strategies for duodenal GISTs: benefits and limitations of minimal resections

Comment on Conservative surgery vs. duodeneopancreatectomy in primary duodenal gastrointestinal stromal tumors (GIST): a retrospective review of 114 patients from the French sarcoma group (FSG). [Eur J Surg Oncol. 2014

Gastrointestinal stromal tumors: correlation between symptoms at presentation, tumor location and prognostic factors in 47 consecutive patients

<p>Abstract</p> <p>Background</p> <p>Gastrointestinal stromal tumors (GIST) are mesenchymal tumors of the gastrointestinal tract, usually kit-positive, that are believed to originate from interstitial cell of Cajal, or their related stem cells. The most common clinical presentation of these tumors is gastrointestinal bleeding, otherwise they may cause intestinal obstruction, abdominal pain, a palpable mass, or can be incidentally detected during surgery or endoscopic/radiological procedures. Prognosis is related to the size of the tumor and to the mitotic rate; other prognostic factors are tumor location, tumor resection margins, tumor rupture, and c-kit mutation that may interfere with molecular target therapy efficacy.</p> <p>Aim</p> <p>Primary aim of this study was to report our experience regarding GIST patients, correlating symptoms at presentation with tumor localization and risk factors.</p> <p>Patients and methods</p> <p>47 consecutive patients undergone to surgical resection for GISTs were enrolled in a prospective study from December 1999 to March 2009. Patient's clinical and pathological features were collected and analysed.</p> <p>Results</p> <p>The most common symptom was abdominal pain. Bleeding in the digestive tract and abdominal pain were more frequent in gastric GISTs (58% and 61%); acute abdominal symptoms were more frequent in jejunal and ileal GISTs (40% and 60%), p < 0.05. We reported a mild correlation between the mitotic rate index and symptoms at presentation (p 0.074): this correlation was stronger if GISTs causing "acute abdominal symptoms" were compared with GISTs causing "abdominal pain" as main symptom (p 0.039) and with "incidental" GISTs (p 0.022).</p> <p>We observed an higher prevalence of symptomatic patients in the "high risk/malignant group" of both the Fletcher's and Miettines's classification (p < 0.05).</p> <p>Conclusion</p> <p>According with our findings symptoms correlate to tumor location, to class risk criteria as mitotic index and risk classifications, however we cannot conclude that symptoms are <it>per se </it>predictive of survival or patient's outcome.</p

A case of furuncular myiasis in an Italian patient: a "travel souvenir"

Furuncular myiasis is a parasitosis of the skin that is commonly reported in the tropical areas and is caused by various agents including Dermatobia hominis. Knowledge of myiasis is limited in Italy, resulting in difficulties in its diagnosis and treatment. We report a case of imported furuncular myiasis in a 48 year old Italian patient who returned from Peru. A third stage larva of D. hominis was identified and the diagnosis of myiasis was confirmed

Persistent alveolar air leak following pulmonary lobectomy: an old problem in a modern era

Persistent alveolar air leak (PAAL) after major lung resection remains a common complication in thoracic surgery. The aim of this study was to identify a subset of patients with high risk of developing PAAL after pulmonary lobectomy. Another objective was to evaluate the influence of PAAL on postoperative complications and length of hospital stay. A retrospective analysis on 895 patients undergoing pulmonary lobectomy from January 2014 to December 2019 was performed. PAAL was defined as air leak lasting more than 5 days after lung surgery. Univariate analyses and logistic regressions were performed to identify the predictors of PAAL. A backward selection algorithm was used to identify the optimal set of predictors. The incidence of PAAL was 8.2% (74/895). Male gender (p=0.017), BMI (p<0.001), transient ischemic attack (p=0.031), FEV1 (p=0.018), lobectomy combined with adjacent subsegmentectomy (p=0.018), partial and extended pleural adhesions (p=0.033 and p=0.038, respectively) were identified as independent risk factors for PAAL through logistic regression. A weak positive correlation was found between video-assisted thoracic surgery (VATS) and PAAL following pulmonary lobectomy (p=0.100). PAAL was found to be associated with higher risk of postoperative morbidity (p=0.002) and with longer hospital stay (p<0.001). Both preoperative and intraoperative risk factors may be responsible for PAAL after pulmonary lobectomy. VATS does not appear to prevent this postoperative complication. An alveolar air leak lasting beyond 5 days after pulmonary lobectomy is associated with worse postoperative outcomes.

Raman-markers of X-ray radiation damage of proteins

Despite their high relevance, the mechanisms of X-ray radiation damage on protein structure yet have to be completely established. Here, we used Raman microspectrophotometry to follow X-ray-induced chemical modifications on the structure of the model protein bovine pancreatic ribonuclease (RNase A). The combination of dose-dependent Raman spectra and ultrahigh resolution (eight structures solved using data collected between 0.85 and 1.17 Å resolution on the same single crystal) allowed direct observation of several radiation damage events, including covalent bond breakages and formation of radicals. Our results are relevant for analytical photodamage detection and provide implications for a detailed understanding of the mechanisms of photoproduct formatio

[Obturator foramen bypass for revascularization of the leg with infection of the femoral area. A clinical case].

Infection of the femoral artery together with limb acute ischemia represent for the vascular surgeon a challenging condition to manage. To solve this complicated vascular problem in the groin, the obturator foramen bypass has been described as an alternative procedure for ischemic limb salvage. The authors report their experience with a diabetic patient admitted in critical conditions with an ischemic leg and sepsis of the femoral area due to an infected extra-anatomical crossover femoro-femoral bypass complicated by hemorrhagia and which was partially removed in another Hospital. Limb revascularization was achieved by an obturator foramen PTFE expanded iliopopliteal bypass. The residual infected prosthesic stump was, thereafter, removed from the groin wound. The post-operative period was uneventful and the patient was discharged in the XIII post operative day. At follow-up, latest control at 10 months (July 1993) documented a patent graft and an ankle pressure index > 1. This experience, and a review of the literature, confirm the validity of the obturator foramen bypass as a route of choice for infected femoral artery and ischemic limb salvage

Revascularization of the ischemic diabetic foot by popliteal-to-distal bypass

BACKGROUND: Diabetic foot revascularization by popliteal-to-distal bypass is a procedure for limb salvage spread in the last decade. METHODS: The authors report their experience with a consecutive series of 15 ischemic feet (mean transcutaneous oxygen 5.3 +/- 4.1 mmHg) with gangrenous lesions due to extensive tibial arteries occlusive disease beginning at the popliteal artery trifurcation (9 cases) or involving the distal popliteal artery (6 cases). Limb salvage was achieved by popliteal-to-distal bypass with autogenous inverted saphenous vein. RESULTS: No operative death was observed. At a mean follow-up of 35 +/- 23 months (range 3-84 months) 4 bypasses were occluded and two were surgically revised after 4 and 50 months from surgery and subsequently remained patent. One patient was submitted to a major amputation. By life table analysis the cumulative primary and secondary patency and limb salvage rates for this group of diabetic patients were at 2 years 79.3%, 86.2% and 93.1% respectively (SE < 10%). CONCLUSIONS: This small experience and a review of the literature confirm the validity of the popliteal-to-distal bypass and the need for a more aggressive vascular surgical attitude to treat the ischemic diabetic foot