Decellularization of Wharton's Jelly Increases Its Bioactivity and Antibacterial Properties.

The field of regenerative medicine has recently seen an emerging trend toward decellularized extracellular matrix (ECM) as a biological scaffold for stem cell-delivery. Human umbilical cord represents a valuable opportunity from both technical and ethical point of view to obtain allogenic ECM. Herein, we established a protocol, allowing the full removal of cell membranes and nuclei moieties from Wharton's jelly (WJ) tissue. No alterations in the ECM components (i.e., collagen, GAG content, and growth factors), physical (i.e., porosity and swelling) and mechanical (i.e., linear tensile modulus) properties were noticed following WJ processing. Furthermore, no effect of the tissue processing on macromolecules and growth factors retention was observed, assuring thus a suitable bioactive matrix for cell maintenance upon recellularization. Based on the in vitro and in vivo biodegradability and stromal cell homing capabilities, decellularized WJ could provide an ideal substrate for stromal cells adhesion and colonization. Interestingly, the tissue processing increased the antibacterial and antiadhesive properties of WJ against Staphylococcus aureus and Staphylococcus epidermidis pathogens. Altogether, our results indicate that decellularized WJ matrix is able to limit Staphylococcus-related infections and to promote stromal cell homing, thus offering a versatile scaffold for tissue regenerative medicine.

Bone marrow mesenchymal stem cells offer an immune-privileged niche to Cutibacterium acnes in case of implant-associated osteomyelitis.

Considered as some of the most devastating complications, Cutibacterium acnes (C. acnes)-related osteomyelitis are among the hardest infections to diagnose and treat. Mesenchymal stem cells (MSCs) secrete number of immunomodulatory and antimicrobial soluble factors, making them an attractive treatment for bacterial infection. In this study, we examined MSCs/C. acnes interaction and analyzed the subsequent MSCs and bacteria's behaviors. Human bone marrow-derived MSCs were infected by C. acnes clinical strain harvested from non-infected bone site. Following 3 h of interaction, around 4% of bacteria were found in the intracellular compartment. Infected MSCs increased the secretion of prostaglandin E2 and indolamine 2,3 dioxygenase immunomodulatory mediators. Viable intracellular bacteria analyzed by infrared spectroscopy and atomic force microscopy revealed deep modifications in the wall features. In comparison with unchallenged bacteria, the viable intracellular bacteria showed (i) an increase in biofilm formation on orthopaedical-based materials, (ii) an increase in the invasiveness of osteoblasts and (iii) persistence in macrophage, suggesting the acquisition of virulence factors. Overall, these results showed a direct impact of C. acnes on bone marrow-derived MSCs, suggesting that blocking the C. acnes/MSCs interactions may represent an important new approach to manage chronic osteomyelitis infections. STATEMENT OF SIGNIFICANCE: The interaction of bone commensal C. acnes with bone marrow mesenchymal stem cells induces modifications in C. acnes wall characteristics. These bacteria increased (i) the biofilm formation on orthopaedical-based materials, (ii) the invasiveness of bone forming cells and (iii) the resistance to macrophage clearance through the modification of the wall nano-features and/or the increase in catalase production.

Bioinspired Nanofeatured Substrates: Suitable Environment for Bone Regeneration.

Bone mimicking coatings provide a complex microenvironment in which material, through its inherent properties (such as nanostructure and composition), affects the commitment of stem cells into bone lineage and the production of bone tissue regulating factors required for bone healing and regeneration. Herein, a bioactive mineral/biopolymer composite made of calcium phosphate/chitosan and hyaluronic acid (CaP-CHI-HA) was elaborated using a versatile simultaneous spray coating of interacting species. The resulting CaP-CHI-HA coating was mainly constituted of bioactive, carbonated and crystalline hydroxyapatite with 277 ± 98 nm of roughness, 1 µm of thickness, and 2.3 ± 1 GPa of stiffness. After five days of culture, CaP-CHI-HA suggested a synergistic effect of intrinsic biophysical features and biopolymers on stem cell mechanobiology and nuclear organization, leading to the expression of an early osteoblast-like phenotype and the production of bone tissue regulating factors such as osteoprotegerin and vascular endothelial growth factor. More interestingly, amalgamation with biopolymers conferred to the mineral a bacterial antiadhesive property. These significant data shed light on the potential regenerative application of CaP-CHI-HA bioinspired coating in providing a suitable environment for stem cell bone regeneration and an ideal strategy to prevent implant-associated infections.

Identification of a founder BRCA1 mutation in the Moroccan population.

Breast cancer (BC) is the most frequent cancer among women in Morocco. However, the role of the most prevalent BC-predisposing genes, BRCA1 and BRCA2, has been largely unexplored. To help define the role of BRCA1 in BC in Morocco, we characterized the first potential BRCA1 founder mutation in this population. Genetic testing of BRCA1 and BRCA2 in BC high-risk families identified mutation BRCA1 c.5309G>T, p.(Gly1770Val) or G1770V in five independent families from Morocco, suggesting a founder effect. To confirm this hypothesis, haplotype construction was performed using seven intragenic and flanking BRCA1 microsatellite markers. Clinical data were also compiled. Clinical data from carriers of mutation G1770V correspond to data from carriers of BRCA1 pathogenic mutations. Microsatellite analysis showed a common haplotype for the five families in a region comprising 1.54 Mb, confirming G1770V as the first specific founder BRCA1 mutation in the Moroccan population. Our findings contribute to a better understanding of BC genetics in the Moroccan population. Nevertheless, comprehensive studies of mutation G1770V in large series of BC patients from Morocco are needed to assess the real prevalence of this mutation and to improve genetic testing and risk assessment in this population.

Sorption of phthalic acid at goethite surfaces under flow-through conditions.

The objectives of this investigation were to improve our understanding of organic acid transport in porous media by focusing on a model system involving phthalic acid and goethite-coated sand (GCS). This was specifically made by first recalibrating a molecularly sound phthalate surface complexation model to GCS and then applying this model to describe breakthrough curves (BTC) in a GCS packed column. ATR-FTIR spectra of phthalic acid adsorbed at goethite surfaces at pH 3.0 and 6.0 and at loadings from 2.0 to 40.8 µmol/m(2) confirmed the coexistence of metal-bonded (MB) and hydrogen-bonded (HB) complexes at low pH and the predominance of HB complexes at high pH. This concept was incorporated into a surface complexation model used to describe BTC at influent pH (pH(in)) values of 3.0, 6.0, and 7.8. The BTC revealed strongly pH-dependent behaviors. At pH(in) 3.0, the BTC revealed one front/plateau behavior while at pH(in) 6.0 two fronts/plateaus occurred. The existence of a second front/plateau led to an overestimation of the sorbed amount compared to that observed in the batch and caused a failure in the prediction of BTC. Additional column investigations suggested that surface loadings of nonspecifically adsorbed complexes could vary with pH and ionic strength and that the two-step breakthrough behavior may have emerged as a result of the formation of surface species of different natures than those during the first step, with the latter even serving as attachment sites corresponding to the second step. These findings call for refinements in current day modeling approaches used in reactive transport studies.

Surface complexation of 2,5-dihydroxybenzoic acid (gentisic acid) at the nanosized hematite-water interface: an ATR-FTIR study and modeling approach.

In this study, characteristic interactions of 2,5-dihydroxybenzoic acid (or gentisic acid, GA) with the surface of 15-nm-sized hematite (α-Fe2O3) were studied by combining batch macroscopic experiments, in situ attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopic investigations, and surface complexation modeling. A correlation between the pH, the amount of adsorbed GA, and the amount of Fe(III) released from the hematite surface was observed, whereas the dissolution of hematite nanoparticles became significant only at low pH and high ligand loading. From the ATR-FTIR results, two aqueous complex structures have been identified depending on pH. At the hematite-water interface, the occurrence of one deprotonated inner-sphere "bidentate" complex and one outer-sphere complex was suggested through all of the investigated pH range. At high surface coverage, variations of vibrational band intensities were observed, suggesting the occurrence of nonspecific molecular interactions. The macroscopic results (i.e., GA batch sorption and the ligand-promoted dissolution of hematite) obtained under a wide range of experimental conditions corroborated the ATR-FTIR microscopic findings. GA adsorption was described by a surface complexation model fitted to pH-adsorption curves with 1 mM sorbate concentration in the pH range of 3-9. Two surface complexes (one outer-sphere species (≡FeOH2)2···H2L((1+,1-)) and one inner-sphere species (≡Fe)2H2L) were proposed using the three-plane model. The inner-sphere complexes were predominant at low pH values, and the relative concentrations of the outer-sphere species increased with the pH increase. The formation of inner-sphere complexes at acidic pH values can promote the dissolution of nanosized hematite. At high solute loading, GA oxidation into carboxybenzoquinone compounds by ferric species was suspected, suggesting the occurrence of a redox reaction analogous to that of hydroquinone compounds.

Donor screening for hepatitis B virus infection in a cell and tissue bank.

BACKGROUND AND OBJECTIVES: Hepatitis B virus (HBV) has been transmitted by tissue transplantation. In order to reduce the risk of HBV transmission, testing for antibody to HBV core antigen (anti-HBc) is used in addition to testing for hepatitis B surface antigen (HBsAg) in many blood centers and tissue banks. DESIGN AND METHODS: We retrospectively analyzed the results of HBV assays in tissue donors. All tissue donors were tested for HBsAg and anti-HBc. All anti-HBc positive sera were tested for the antibody to HBsAg (anti-HBs). From July 2006, an HBV nucleic acid testing (NAT) assay was also performed. RESULTS: A total of 6855 tissue donors from January 1999 till July 2007 were tested for HBV assays: 4756 women and 2099 men. Positive HBsAg was found in 23 (0.36%) living donors, while no multiorgan or cord blood (CB) donor was found to be positive for HBsAg. Positive anti-HBc was found in 80 multiorgan donors (12.94%), 599 living donors (17.84%), and 103 CB donors (3.57%) (P<0.005), while isolated anti-HBc was found in 12 multiorgan (1.94%), in 126 living tissue donors (3.75%), and in 8 CB donors (0.28%). A total of 1310 donors were analyzed for single-sample DNA HBV NAT assay. DISCUSSION: We consider that anti-HBc and NAT assays must both still be performed in addition to HBsAg assay for HBV screening in tissue donors. All these tests will be useful in order to define an algorithm for safe and efficient management of the tissue bank.

[Complications of endoscopic retrograde cholangiopancreatography in patients aged more than 90 years old]. / Complicaciones de la colangiopancreatografía retrógrada endoscópica en pacientes mayores de 90 años.

INTRODUCTION: To evaluate the effectiveness of endoscopic retrograde cholangiopancreatography (ERCP) and the complication rates of this procedure in patients aged 90 years and older. PATIENTS AND METHOD: A descriptive, prospective study including 42 endoscopic procedures performed from first January 2001 until first June 2004 in 36 patients (7 males and 29 females) was performed. The mean age was 91 years (range 90-96 years). All patients underwent the following: a) clinical evaluation before and after endoscopic exploration; b) evaluation of the success or failure of the endoscopic procedure and c) assessment of complications (perforation, hemorrhage, pancreatitis and infection). Concurrent associated illnesses, as well as the existence of anatomical alterations in Vaters papilla (duodenal diverticula), were also evaluated. RESULTS: ERCP was successful in 85.7% of all explorations performed. Twenty-three patients (63.8%) had one or more major associated diseases. In 15 patients (33.3%) Vaters papilla was associated with duodenal diverticula. The complication rates were as follows: 1) acute pancreatitis in 2 explorations (4.7%), one mild (2.35%) and the other moderate (2.35%); 2) hemorrhage after endoscopic sphincterotomy in 2.8% of patients (1/35); 3) bacteriemia in one patient (2.3%) and cholangitis in one patient (2.3%), with no cases of secondary cholecystitis; 4) hypoxemia in one patient. There were no perforations or deaths related to the procedure. CONCLUSION: ERCP is a safe and effective technique with a low complication rate in patients aged 90 years or older.

[Colonoscopic follow-up of patients undergoing curative resection of colorectal cancer]. / Seguimiento colonoscópico de los pacientes intervenidos de carcinoma colorrectal con intención curativa.

AIM: To investigate the role of colonoscopy in the follow-up of patients undergoing curative resection of colorectal cancer. MATERIAL AND METHODS: A prospective study was performed of 102 patients with colorectal cancer who underwent surgery with curative intention. Postoperative colonoscopic follow-up was a minimum of 5 years. RESULTS: There were 62 males and 40 females. The mean duration of follow-up was 73.4 months. Synchronous polyps were found in 44.1% (114 in 45 patients) and metachronous polyps in 33.4% (64 in 34 patients). Synchronous carcinoma was detected in 7.8% (9 in 8 patients), metachronous carcinoma in 1.9% (2 in 2 patients) and suture recurrence in 4.9% (5 in 5 patients). Metachronous polyps developed in 55.5% of the patients with synchronous polyps and in only 15.8% of those with no synchronous polyps (p < 0.00005); the odds ratio was 6.67. Colonoscopy diagnosed 92 synchronous polyps and 64 metachronous polyps; of these, 34 were found to be significant(in 22 patients). Colonoscopy diagnosed 5 synchronous carcinomas; in 3 of these (polyps with non-invasive carcinoma) polypectomy constituted definitive therapy and in the remaining 2, curative resection was achieved. Colonoscopy diagnosed 2 stage C2 metachronous carcinomas at 63 and 94 months. Curative resection was achieved in both cases. Colonoscopic follow-up diagnosed 2 suture recurrences and resection was potentially curative. CONCLUSIONS: Colonoscopy was found to play an essential role in 30% of the patients. The technique allowed the early diagnosis of synchronous carcinomas and curative treatment of metachronous carcinomas and demonstrated that the presence of synchronous polyps increases the risk of developing metachronous polyps.

[Magnetic resonance cholangiopancreatography (MRCP) versus endoscopic retrograde cholangiopancreatography (ERCP): diagnostic usefulness]. / Colangiopancreatografía por resonancia magnética (CPRM) frente a colangiopancreatografía retrógrada endoscópica (CPRE): utilidad diagnóstica.

Magnetic resonance cholangiopancreatography (MRCP) is a new noninvasive technique to examine the biliopancreatic tract that have a high diagnostic accuracy. Thus it becomes an appealing modality that can avoid invasive approaches. The purpose of this study was to evaluate the sensitivity and specificity of MRCP in comparison to endoscopic retrograde cholangiopancreatography (ERCP). We studied 41 patients (24 male, 17 female), median age 64.2 years (range 20 to 86 years), in which MRCP and later ERCP were performed; results of both techniques were compared. In the assessment of biliary tract (n = 39), sensitivity/specificity was 100/94.4% in normal bile ducts (n = 18); 100/100% in choledocholithiasis (n = 13); 100/100% in sphincter of Oddi dysfunction (n = 2), and 100/83.3% in neoplasm (3 ampullary tumors, 2 cholangiocarcinomas). In the evaluation of pancreatic duct (n = 32), sensitivity/specificity was 100/95.8% in normal pancreatic duct (n = 23); 80/100% in chronic pancreatitis (n = 5), and 100/75% in pancreatic carcinoma (n = 3). MRCP has very high sensitivity and specificity in the evaluation of the biliary and pancreatic ducts, and can avoid to perform purely diagnostic ERCP, although further studies are required to better assess the effectiveness of the technique.

[A case of tuberculous epiglottitis: an unusual form of presentation]. / Un caso de epiglotitis tuberculosa: una forma inusual de presentación.

A case laryngeal tuberculosis with atypical presentation simulating epiglottitis is presented. The topic is reviewed and discussed.

[Does the antisecretory agent used affect the evolution of upper digestive hemorrhage?]. / Afecta a la evolución de la hemorragia digestiva alta el antisecretor utilizado?

OBJECTIVE: To investigate whether omeprazole has improved morbidity-mortality among patients with upper gastrointestinal bleeding of non-variceal origin in comparison with ranitidine. MATERIAL AND METHODS: Prospective, randomized and open study. We study 519 consecutive patients admitted to our Service between June 1991 and January 1993 for upper gastrointestinal bleeding of peptic origin, dividing the patients into two randomized groups that were homogeneous in terms of age, sex, previous history of gastric disease and upper gastrointestinal bleeding, intake of non-steroidal antiinflammatory drugs, and the severity of bleeding on admittance. Thus, Group A consisted of 252 patients treated immediately upon arrival at the emergency ward with 50 mg intravenous ranitidine, followed by a further 50 mg every 6 hours. Group B in turn consisted of 267 patients initially given a bolus dose of 80 mg omeprazole intravenously, followed by an additional 40 mg every 8 hours for 48 hours. Forty mg were subsequently administered every 12 hours until hospital discharge. Endoscopy was performed in all cases within the first 24 hours following admittance, those patients with active upper gastrointestinal bleeding resulted from Forrest-type ulcer of subjected to endoscopic sclerotherapy were excluded. RESULTS: Duodenal ulcer was the most common cause of bleeding, followed by gastric ulcer and acute lesions of the mucosa. Emphasis should be placed on the high incidence of previous non-steroidal antiinflammatory drug intake in our series (54.5%). We encountered no statistically significant differences between the two groups on comparing bleeding stigmata, transfusion requirements, recurrences, emergency surgery, the duration of hospital stay, and mortality. CONCLUSIONS: Both drugs were found to possess a similar efficacy in treating upper gastrointestinal bleeding of peptic origin.

Segmental tuberculosis of the colon diagnosed by colonoscopy.

We describe the case of a woman with rectorrhagia and rectal tenesmus. Colonoscopy revealed a 3-4 cm-long ulcerated lesion with a reduced colon lumen 35 cm from the anus, and multiple biopsies were obtained from the ulcerated region, but histopathology was non-specific. Biopsy culture was positive for M. tuberculosis. Anti-tuberculous chemotherapy was initiated on the diagnosis of segmental tuberculosis of the colon. Subsequent evolution was favorable, both clinically and endoscopically. Emphasis is placed on the importance of colonoscopy and biopsy in the diagnosis of tuberculosis of the colon.

Hypertrophic pyloric stenosis in the adult.

In view of the low incidence of hypertrophic pyloric stenosis, we present a case of this pathology in a male aged 74. Stenosis was of the diffuse type, associated with gastric ulcer and chronic atrophic gastritis. The patient was admitted to our Service with upper digestive tract hemorrhage after deterioration of the ulcer.