Applications and limits of raman spectroscopy in the study of colonic and pulmonary malformations.

2006/2007Questa tesi nasce dalla collaborazione tra il Dipartimento di Materiali e Risorse Naturali dell’Università degli Studi di Trieste ed il Dipartimento di Chirurgia Pediatrica dell’Ospedale Infantile Burlo Garofalo. L’obiettivo del nostro gruppo di studio era di valutare le possibili applicazioni della spettroscopia Raman nello studio dei tessuti umani, con particolare attenzione verso i tessuti affetti da malformazioni congenite. L’interesse verso la spettroscopia Raman, che è una spettroscopia vibrazionale basata sullo scattering inelastico di fotoni, nasce dal fatto che questa tecnica può fornire dettagli precisi sulla composizione chimica e sulla struttura molecolare di cellule e tessuti. Durante lo svolgersi del progetto, sono state standardizzate le procedure di conservazione e preparazione dei campioni, i quali sono stati prelevati, con il consenso parentale, durante interventi chirurgici. Mediante l’uso di uno spettrometro Raman equipaggiato con un laser emittente luce monocromatica a 785 nm, sono stati analizzati campioni di colon e polmone normale, rappresentativi di un tessuto prevalentemente stratificato e di un parenchima omogeneo. Sono stati studiati anche tessuti polmonari malformati affetti da Malformazione Adenomatoide Cistica (CCAM) e Sequestri Broncopolmonari (BPS). Vengono descritte le procedure di acquisizione e processazione dei dati. Dopo applicazione di un’analisi multivariata come la k-means cluster analisi, sono state ottenute delle pseudo-mappe Raman colorate, che sono state poi confrontate con gli stessi campioni nativi non colorati, apposti su vetrino. Da ogni cluster sono stati estratti gli spettri Raman medi, che sono stati confrontati per evidenziare differenze fra aree diverse del campione. L’assegnazione delle principali bande alle diverse specie chimiche è stata fatta secondo la letteratura. L’analisi Raman è stata in grado di differenziare i diversi strati del colon ( sierosa, muscolatura, sottomucosa, mucosa, plessi nervosi), evidenziando strutture subcellulari in elementi nervosi quali i gangli. Sezioni normali e malformate di polmone hanno dimostrato una clusterizzazione e degli spettri medi diversi, permettendo una differenziazione tra CCAM e BPS, tanto che in un caso la nostra analisi, non concordando con la diagnosi del patologo, ha indotto una revisione dei vetrini e una riformulazione della diagnosi. Gli effetti di ampliamento del segnale Raman per risonanza di cromofori quali il gruppo eme dell’emoglobina con la radiazione a 785 nm sono stati discussi ed abbiamo proposto un metodo per minimizzare il contributo spettrale di questa molecola. Abbiamo inoltre confrontato i dati Raman con i dati ottenuti sugli stessi campioni presso l’Istituto di Chimica Analitica dell’ Università di Dresda mediante un’altra spettroscopia vibrazionale quale la spettroscopia ad Infrarosso. Ci è stata accordata per la discussione di questa tesi la possibilità di presentare i dati, per un confronto fra le due tecniche in relazione a tempi di acquisizione, risoluzione spaziale e spettrale.This thesis originates from a collaboration of the Department of Materials and Natural Resources of the University of Trieste with the Department of Pediatric Surgery of Burlo Garofalo Hospital for Sick Children. The goal of our research group was to evaluate the possible applications of Raman spectroscopy to the study of biological tissue with particular interest toward tissues affected by congenital malformations. The interest toward Raman spectroscopy, which is a vibrational spectroscopy based on inelastic scattering of photons, arises from the fact that this spectroscopic technique can provide details of the chemical composition and molecular structures of cells and tissues. A standard procedure was defined for the preparation and preservation of samples, which were collected during surgical operations. Samples of normal colon and lung, therefore representing a stratified and homogeneous tissue types, were evaluated using a Raman spectrometer, equipped with a 785 nm emitting laser. Lung specimens affected by congenital malformations such as Congenital Cystic Adenomatoid Malformation (CCAM) and Bronchopulmonary Sequestration (BPS) were studied as well. Data acquisition and data processing procedures are described. After application of a multivariate analysis such as k-means clustering, pseudo-color Raman maps of the samples were obtained and compared with the native unstained specimens. Average spectra from the clusters were compared to extract differences among areas within the samples. Assignments of major bands in the spectra to chemical compounds were performed according to previous literature. Raman analysis was able to discriminate between the different layers of colon (serosa, muscles, mucosa, submucosa, nervous plexi), evidencing up to subcellular features in nervous elements such as ganglia. Normal and affected lung specimens showed different predominant clusters and average spectra. Raman spectroscopy could distinguish between CCAM and BPS and in one case prompted our pathologist to review and correct her previous diagnosis. Resonance enhanced Raman signals from chromophors such as the heme group of hemoglobin are evidenced and discussed and a method to minimize spectral contribution of this molecule is proposed. Comparison with another vibrational spectroscopy such as Infrared Spectroscopy showed that these two techniques are complementary rather than alternative spectroscopies. Infrared data from the same samples studied by Raman were acquired at the Institute of Analytical Chemistry of the Dresden University and granted for this dissertation. Acquisition times, spatial and spectral resolution between the two techniques are discussed.XIX Ciclo197

Nocturnal cough and difficulty breathing during exertion in a young boy: Do not miss the forest for the trees

No abstract avaiable

Perforated appendix with abscess: Immediate or interval appendectomy? Some examples to explain our choice

Introduction There are no clear guidelines in the treatment of a perforated appendicitis associated with periappendiceal abscess without generalized peritonitis. Presentation of cases We retrospectively studied six examples of treated children in order to discuss the reasons of our team\u2019s therapeutic approach. Some children were treated with a conservative antibiotic therapy to solve acute abdomen pain, planning a routine interval appendectomy after some months. Others, instead, underwent an immediate appendectomy. Discussion By examining these examples we wanted to highlight how the first approach may be associated with shorter surgery time, fewer overall hospital days, faster refeeding and minor complications. Conclusion Our team\u2019s therapeutic choice, in the case of a perforated appendicitis with an abscess and coprolith is an initial conservative case management followed by a routine interval appendectomy performed not later than 4 months after discharge. Abbreviations CT, computed tomography; CVC, central catheter venous; IA, interval appendectomy; NT, naso-gastric tube; US, ultrasonography; VC, vesical cathete

Adenomyomatosis of the Gallbladder as a Cause of Recurrent Abdominal Pain

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Linfoadenite laterocervicale tubercolare: terapia medica, chirurgica ed effetti paradossi

We report a case of a 1-year-old girl with persistent fever and enlargement of laterocervical lymph nodes on the left side, fluctuant and with erythematous overlying skin. A positive Mantoux skin test first (induration of 20 mm in 72 hours) and then the DNA amplification by polymerase chain reaction (PCR) as well as the culture confirmed the diagnosis of Mycobacterium tuberculosis complex, in particular M. bovis. Nonetheless, after 1 month of standard mycobacterial regimen (isoniazid, rimpaficin, ethambutol, pyrazinamide), she developed new lymph nodes on the same and on the opposite side, apart from the residual ones. She underwent surgery three times (excision of a lymph node, incision and drainage of the others) for the definitive diagnosis and for the excessive enlargement of the nodes with risk of compression of underlying structures and diffusion. A drug resistance was ruled out by antibiogram. Paradoxical upgrading reaction (PUR) to the therapy offers a plausible explanation for this phenomenon, and this is supported by a prompt answer to steroids

Laparoscopic fundoplication after oesophageal atresia repair

Background: Esophageal atresia (EA) is a rare congenital malformation. A high incidence of GER unresponsive to medical management is noted with EA. Literature suggests that complications from GER can persist in adulthood. In paediatric age, laparoscopic treatment is a valid option even if recurrence rate is not negligible. Aims and Objectives: To evaluate our experience with gastro-esophageal reflux (GER) treatment after esophageal atresia (EA) repair. Materials and Methods: We retrospectively analysed 29 consecutive patients treated for EA at birth and studied for GER at our Institute in a period of 11 years. Results: 24/29 (82,7%) cases had symptoms of reflux, 17/29 (58,6%) cases were treated with laparoscopic fundoplication (LF). Three infants were younger than 6 months and had apparent life threatening events (ALTE) condition as principal indication for surgery. No intra-operative complications occurred. 3/17 LF had open surgical conversion due to technical problems. 2/17 cases required a second operation. At the last follow-up: (1) 6/17 (35,3%) of patients healed after the last operation, (2) 8/17 (47,1%) have GER improvement (four still in medical treatment), (3) 2/17 (11,8%) have persistent GER, (4) 1/17 (5,9%) died for causes not related to antireflux surgery. Conclusions: According to literature and to our retrospective analysis, LF for GER after EA repair is feasible, even if recurrence risk is not negligible. Infants less than 6 months old with associated conditions (malformations, gastrostomy/jejunostomy) seem to have a higher failure rate with a greater risk of conversion. Longer follow-up and multicenter experiences would guarantee an adequate surveillance for patients with EA

Un vomito tanto precoce: la spia di un'atresia intestinale

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Meckel’s diverticulum masked by a long period of intermittent recurrent subocclusive episodes

Meckel’s diverticulum (MD) is the most frequent congenital abnormality of the small bowel and it is often difficult to diagnose. It is usually asymptomatic but approximately 4% are symptomatic with complications such as bleeding, intestinal obstruction, and inflammation. The authors report a case of a 7-year-old boy with a one-year history of recurrent periumbilical colicky pain with associated alimentary vomiting, symptoms erroneously related to a cyclic vomiting syndrome but not to MD. The clinical features and the differential diagnostic methods employed for diagnosis of MD are discussed

Adolescent Female with Lower Abdominal Pain and Rebound Tenderness

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Handlebar injury in children: The hidden danger

6no-Pubblicato online 19 settembre 2015reservedmixedPederiva, Federica; Guida, Edoardo; Maschio, Massimo; Rigamonti, Waifro; Gregori, Massimo; Codrich, DanielaPederiva, Federica; Guida, Edoardo; Maschio, Massimo; Rigamonti, Waifro; Gregori, Massimo; Codrich, Daniel