Fatal hemorrhage in two renal graft recipients with multi-drug resistant Pseudomonas aeruginosa infection

Pseudomonas aeruginosa (PA) infections occurring after renal transplantation (RT) represent a potentially life-threatening complication. We present 2 cases of early death following RT in which PA was transmitted, possibly from the donor to the recipients, despite preoperative cultures that were negative. The donor had developed PA-related bilateral pneumonia while in the intensive care unit. However, after appropriate antibiotic therapy, no signs of infection were present at the time of organ retrieval and cultures were negative. Both recipients received a renal graft from the same donor and developed multi-drug resistant (MDR)-PA infections with bacterial phenotypes and resistances similar to the donor. The first recipient died 9 days after RT from rupture of a false aneurysm of the external iliac artery, caused by a fully thickened PA-related arteritis. The second recipient died postoperatively on day 10 after rupture of an aneurysm in the right vertebral artery. Our experience shows that MDR-PA infection early after RT may be a catastrophic event. Specific anti-PA antibiotic therapy in RT patients during the perioperative period is recommended in the case of PA infection in the donor, even after apparent successful therapy with negative cultures.

The association between periodontal diseases and cardiovascular diseases: a narrative review

A possible relationship between periodontal diseases (PDs) and cardiovascular diseases (CVDs) has been supposed and investigated. This review of the literature focuses exclusively on published studies on current theories and models of correlation between PDs and CVDs. A literature search of clinical and observational studies, in the English language, was performed in MEDLINE/PubMed, OVID database and Cochrane Oral Health Group's Trial Register. In addition, references cited in reviewed studies were evaluated for relevant papers. Various mechanisms are described in order to explain this possible association such as a hyper-responsive inflammatory response to chronic infections in predisposed individuals, and systemic effects of periodontal microorganisms including blood platelet aggregation, atheroma formation, increase in lipid levels, activation of acute phase reaction and systemic production of proinflammatory mediators, but a ultimate relation as well as the potential mechanisms have not been defined yet. Controversial result can be related to different method or objectives of studies including different study design, exposure evaluation, outcome variables and clinical endpoints considered. This paper provides a narrative review of the epidemiological studies dealing with the potential association between PDs and cardiovascular events. A precise association between PDs and CVDs, as well as the involved mechanisms are not yet well defined. Additional large-scale longitudinal epidemiological and intervention studies are necessary to validate this association.

Evaluation of trypsin treatment on the inactivation of bovine herpesvirus type 1 on in vitro produced pre-implantation embryos

The aim of this study was to evaluate the efficiency of trypsin treatment on the inactivation of bovine herpesvirus type 1 (BoHV-1) on in vitro produced by fertilization and artificially infected bovine embryos. Bovine embryos on day 7 were exposed with 10 microl of BoHV-1, Los Angeles strain 10(7.5) TCID. These embryos and control embryos were divided in two groups: submitted to the sequential washes or to the trypsin treatment according to the International Embryo Transfer Society (IETS) guidelines. The embryos and the last washing drop of each group were used as inoculum to infect Madin Darby bovine kidney (MDBK) cells and submitted to nested PCR reaction using the primer that encodes the gene conserved region of virus glycoprotein gB. The data have shown that the control embryos and their last washing drop were negative. The exposed embryos that were treated with trypsin have shown positive results on the n-PCR and MDBK culture, and their last washing drop were negative. Our data have demonstrated that the trypsin treatment was not able to eliminate the BHV-1 of the embryos, suggesting an interaction between virus and embryo.

The Role of Liver Transplantation in the Treatment of Hereditary Hemorrhagic Telangiectasia: A Short Literature Review

The liver is involved in up to 73% of patients suffering from hereditary hemorrhagic telangiectasia (HHT), but only some of them become symptomatic. Although management is often conservative, sometimes a more aggressive approach is required. The role of surgery is still undefined. Open ligation, banding, or closure of the arteriovenous malformation feeding artery have been proposed but rejected, as they are followed by an unacceptably high incidence of complications, derived from ischemia of the biliary tree. Orthotopic liver transplantation (OLT) has been successfully attempted in 28 patients with cardiac, biliary, or portal hypertension as well as mixed clinical presentations. Twenty-four were alive at time of data collection. Cardiovascular and pulmonary functions have improved after the operation in most cases. Intrahepatic relapse of the hallmark lesion of the disease (telangiectasia and arterovenous malformation) has been recently described in two cases. OLT represents a valuable therapeutic option for hepatic-based HHT, provided early diagnosis and referral to a specialized unit.

A combined treatment regimen for desquamative gingivitis in patients with oral lichen planus

BACKGROUND

Chronic desquamative gingivitis (DG) is a condition characterized by erythema, ulceration, and desquamation of the free and attached gingiva, usually expression of a district-systemic disease, such as oral lichen planus (OLP).

METHODS

A combined protocol of oral hygiene and topic corticosteroid therapy was applied in 30 patients with DG associated with OLP. Plaque index (PI) and bleeding on probing (BoP) were evaluated at baseline and after 3 months.

RESULTS

PI scoring was significantly lower after treatment in anterior, posterior, and all sites (P < 0.0001) as well as in vestibular and lingual ones (P < 0.0001 and P = 0.0001, respectively). BoP measures were found to be reduced significantly to 22.94% in a full-mouth evaluation (P < 0.0001; OR = 2.633; 95% CI: 2.2685-3.0561) as well as in each specific site (P < 0.0001).

CONCLUSION

This clinical trial validated the efficacy, in patients with DG associated with OLP, of a protocol based on professional oral hygiene and self-performed plaque control measures in improving of gingival health status.

HPV infection in relation to OSCC histological grading and TNM stage. Evaluation by traditional statistics and fuzzy logic model

We aimed to evaluate if in oral squamous cell carcinoma (OSCC) there is a relationship between histological grading (HG), TNM clinical stage and HPV infection; and to study the performance of fuzzy logic compared to traditional statistics, in the analysis of HPV status and correlates of OSCC. In cross-sectional analysis, the study group comprised 63 patients (mean age 68.89 years (SD +/-11.78), range (32-93); males 28 (44.4%), females 35 (55.6%)) with OSCC histologically diagnosed. HPV-DNA was studied in exfoliated oral epithelial cells by nested PCR (MY09/MY11 and GP5+/GP6+ primers). Data were analysed in parallel by traditional statistics with multivariate analysis and a fuzzy logic (FL) technique (membership functions as input, the ANFIS methodology, and the Sugeno's model of first order). HPV infection was detected in 24/63 (38.1%) of OSCC, as being HPV+ve 14/36 (38.9%) in G1, 7/18 (38.9%) in G2, and 3/9 (33.3%) in G3; HPV+ve 8/33 (24.2%) in Stage I, 9/12 (75.0%) in Stage II, 6/11(54.5%) in Stage III, and 1/7 (14.3%) in Stage IV. In both methods of analysis, no significantly increased risk of HPV infection was found for any HG score; whereas, TNM stage II was significantly associated to HPV infection (p=0.004; OR=9.375 (95% CI=2.030:43.30); OR'=11.148 (95% CI=1.951:43.30)), and, in particular, to primary tumour size T2 (p=0.0036; OR=7.812 (95% CI=1.914:31.890); OR'=9.414 (95% CI=1.846:48.013)); FL (% of prevision: 79.8; Root Mean-Square Error (RMSE): 0.29). No association was found between HPV infection and any demographical variable. Our findings show an association between HPV infection with TNM (stage II-T2), but not with histological grading of OSCC. Also, FL seems to be an additional effective tool in analysing the relationship of HPV infection with correlates of OSCC.

Urologic complications in kidney transplantation

Urologic complications in kidney transplantation have an incidence ranging from 3% to 20%, representing an important cause of organ loss. From January 2001 to September 2004, 123 renal transplantations were performed using an immunosuppressive protocol including basiliximab, mycophenolate mofetil, calcineurin inhibitors, and steroids. The surgical technique was vascular anastomoses to external iliac vessels, and ureteral anastomosis according to Lich Gregoire technique using a JJ ureteral stent. We report 5 renal complications (4.2%) and 4 extrarenal complications (3.5%), the majority of which required corrective surgery. The surgical strategy uses the clinical condition of the donor and the recipient; the anatomic anomalies of the graft, and a reduced cold ischemia time. Moreover, a reduction in acute rejection episodes and immediate renal function has been fundamental to reduce urologic complications. In fact, the main cause of urologic complications is ureteral ischemia, linked both to backtable surgery and to rejection episodes. Another important factor in the reduction of early urologic complications has been the routine use of a JJ stent, which allowed us a conservative approach in this setting.

Malignancies After Kidney Transplantation

The most effective treatment of end-stage renal disease is renal transplantation; its superiority to prolong the longevity of patients is well established. Patient and graft survivals have improved with more potent immunosuppression but this advance has been associated with an increased incidence of cancer. The aim of this study was to assess the prevalence of cancer among 265 kidney transplant recipients engrafted between 1968 and October 2004. The overall prevalence of de novo malignancies was 3%. The mean age at diagnosis was 53.3 years (range, 28-63 years) and the duration of the transplant was 11.6 years (range, 0.3-33 years). One patient among 127 (0.8%) who had a history of less than 3 years under immunosuppression, developed a posttransplantation lymphoproliferative disorder (PTLD). Among the 138 patients who had more than 3 years immunosuppression, 7 (5%) developed neoplasms of vulva, colon, native kidneys, prostatic gland, and ovary. One patient was affected by de novo carcinoma in the transplanted kidney. Compared with other published studies, our early cancer prevalence is low, possibly due to a careful history before grafting, good HLA matching, and abstinence from anti-T-cell therapy for treatment of acute rejection episodes. The low level of immunosuppression may account for the low prevalence of neoplasia. The risk of developing a malignancy increases with long-term immunosuppression, comparable with most reports.

Infectious Complications in the Renal Transplant Recipient

The aim of this study was to estimate the incidence of infectious diseases in a group of patients who underwent kidney transplantation from January 1, 2004 to September 30, 2004, including 121 operations, with 119 from cadaveric and 2 from living donors. The protocol sought herpes viruses (CMV, VZV, and EBV), hepatitis viruses, human immunodeficiency virus, T. gondii, M. tubercolosis, and T. pallidum. Therapy for CMV was used both as prophylaxis in immunoglobulin (Ig)G-negative recipients from IgG-positive donors and preemptive therapy, that is, before the appearance of clinical symptoms, but after viremia reached borderline levels. For VZV infections, the treatment started after the appearance of papulo-vesicular cutaneous eruptions and antibody positivity. The treatment for pneumonia consisted of empirical therapy after radiography; for pyelonephritis, antibiotic therapy was based on the results of kidney echography, blood culture, and urine culture. Infectious complications appeared in 25 patients (20.7%), 3 of the which were polymicrobic: 12 CMV infections, 9 VZV infections, 3 pneumoniae, 4 pyelonephritis, and 1 salmonellosis. The most frequent infection was CMV, which occurred in the first 3 months after transplantation in 9 of 12 cases. This study showed that a knowledge of infection prevalence can help the physician to establish a more specific, efficacious antimicrobial therapy, despite the laboratory response not being available in a short time.

Transbuccal tablets of carbamazepine: formulation, release and absorption pattern

Tranbsuccal drug administration is an attractive method, as it has several advantages especially with respect to peroral delivery. Here we report: i) the aptitude of carbamazepine (CBZ) to penetrate porcine buccal mucosa and reconstituted human oral (RHO) epithelium; ii) three different tablet formulations for transbuccal administration; iii) the drug release rate from tablets. CBZ permeation through the buccal mucosa was investigated by using two different bi-compartmental open models: Franz cells for porcine buccal mucosa and Transwell diffusion cells system for RHO epithelium. Results, expressed as drug flux (Js) and permeability coefficients (Kp), indicated that CBZ well penetrates the membrane and arrives in the acceptor phase. Js and Kp resulted 7x10(-2) mg/cm2h and 0.23 cm/h for in vitro experiments and 1.81 x 10(-2) mg/cm2h and 4.57 x 10(-2) cm/h for ex vivo experiments. The flux is extensively affected by the membrane thickness. The CBZ release from three different formulations of tablets, prepared with loaded microspheres, loaded matrices, and conventional compressed physical mixture of components was studied. Using the new formulated "non-conventional" tablets prolonged drug release was obtained. Loaded matrix tablets discharged CBZ faster than microsphere tablets (17% and 12% in about 2.5 h respectively). Results indicate the possibility of administering CBZ on buccal mucosa.

Life at depth: Photobacterium profundum genome sequence and expression analysis

Deep-sea life requires adaptation to high pressure, an extreme yet common condition given that oceans cover 70% of Earth's surface and have an average depth of 3800 meters. Survival at such depths requires specific adaptation but, compared with other extreme conditions, high pressure has received little attention. Recently, Photobacterium profundum strain SS9 has been adopted as a model for piezophily. Here we report its genome sequence (6.4 megabase pairs) and transcriptome analysis. The results provide a first glimpse into the molecular basis for life in the largest portion of the biosphere, revealing high metabolic versatility.

p53 can inhibit cell proliferation through caspase-mediated cleavage of ERK2/MAPK

Stimulation of the Ras/MAPK cascade can either activate p53 and promote replicative senescence and apoptosis, or degrade p53 and promote cell survival. Here we show that p53 can directly counteract the Ras/MAPK signaling by inactivating ERK2/MAPK. This inactivation is due to a caspase cleavage of the ERK2 protein and contributes to p53-mediated growth arrest. We found that in Ras-transformed cells, growth arrest induced by p53, but not p21(Waf1), is associated with a strong reduction in ERK2 activity, phosphorylation, and protein half-life, and with the appearance of caspase activity. Likewise, DNA damage-induced cell cycle arrest correlates with p53-dependent ERK2 downregulation and caspase activation. Furthermore, caspase inhibitors or expression of a caspase-resistant ERK2 mutant interfere with ERK2 cleavage and restore proliferation in the presence of p53 activation, indicating that caspase-mediated ERK2 degradation contributes to p53-induced growth arrest. These findings strongly point to ERK2 as a novel p53 target in growth suppression.

Proliferative verrucous vs conventional leukoplakia: no significantly increased risk of HPV infection

Proliferative verrucous leukoplakia (PVL) is a very aggressive form of oral leukoplakia (OL) with high morbidity and mortality rates, hypothesised to be linked to HPV infection. This study aimed to determine the presence of HPV DNA in PVL in comparison with OL, and in relation to social-demographical variables (age, gender, smoking and drinking habits) in an Italian multi-centric hospital-based study. The study group consisted of 58 cases of PVL and 90 cases of OL as controls (47 homogeneous (H) and 43 non-homogeneous (non-H) form), both recruited from four Italian cohorts. HPV DNA was identified in exfoliated mucosal cells by nested PCR (nPCR) with MY09/MY11 and GP5+/GP6+ primer pairs and the HPV genotype determined by direct DNA sequencing. HPV DNA was found in 24.1% (14/58)of PVL and in 25.5% (23/90) of OL; there was thus no significant difference found between PVL and OL (both forms) for risk of HPV infection (OR=0.93; 95% IC:0.432-1.985). Similarly, in both groups of PVL and OL lesions, no statistic association was found between any demographical variable considered and HPV infection. HPV-18 was the most frequently detected genotype in all tissues, being found in 78.5% and 60.8% of HPV+ve PVL and OL, respectively. Other more rarely detected genotypes were HPV-16 (28.6% in PVL and 13% in OL), HPV-6 (17.4% in OL) and HPV-53 (8.8% in OL). PVL does not appear more likely to be associated to HPV infection than conventional OL lesions.

The small bovine amelogenin LRAP fails to rescue the amelogenin null phenotype

Amelogenins are the most abundant secreted proteins in developing dental enamel. These evolutionarily-conserved proteins have important roles in enamel mineral formation, as mutations within the amelogenin gene coding region lead to defects in enamel thickness or mineral structure. Because of extensive alternative splicing of the primary RNA transcript and proteolytic processing of the secreted proteins, it has been difficult to assign functions to individual amelogenins. To address the function of one of the amelogenins, we have created a transgenic mouse that expresses bovine leucine-rich amelogenin peptide (LRAP) in the enamel-secreting ameloblast cells of the dental organ. Our strategy was to breed this transgenic mouse with the recently generated amelogenin knockout mouse, which makes none of the amelogenin proteins and has a severe hypoplastic and disorganized enamel phenotype. It was found that LRAP does not rescue the enamel defect in amelogenin null mice, and enamel remains hypoplastic and disorganized in the presence of this small amelogenin. In addition, LRAP overexpression in the transgenic mouse (wildtype background) leads to pitting in the enamel surface, which may result from excess protein production or altered protein processing due to minor differences between the amino acid compositions of murine and bovine LRAP. Since introduction of bovine LRAP into the amelogenin null mouse does not restore normal enamel structure, it is concluded that other amelogenin proteins are essential for normal appearance and function.

Genotyping and antifungal susceptibility of human subgingival Candida albicans isolates

Subgingival colonization by Candida albicans has been described in human immunodeficiency virus (HIV)-infected individuals, but subgingival isolates have scarcely been characterized, particularly with respect to genotype and antifungal susceptibility. A series of 29 subgingival strains of C. albicans isolated from nine HIV-infected individuals was typed by electrophoretic karyotyping and tested for susceptibility to fluconazole, itraconazole, the new investigational triazole posaconazole and amphotericin B. DNA typing showed genetic heterogeneity within subgingival isolates, as almost every individual harbored his/her own specific isolate. Genetic identity was usually demonstrated within oral and subgingival isolates simultaneously collected from the same individual, but a number of DNA types were found to be unique to subgingival strains. These findings suggest that colonization is not just the result of Candida spreading from oral surfaces, and that subgingivally adapted strains could be involved. All isolates were susceptible to all the triazole drugs tested and amphotericin B. Additional studies on subgingival Candida colonization and further characterization of subgingival isolates are now required to clarify the role of Candida as opportunistic periodontal pathogen.

[The effect of instrumentation on original apical foramen shape using steel vs niti rotatory: computerized analysis]

BACKGROUND

A fundamental requirement to obtain a correct endodontic preparation depends on the respect, during cleaning and shaping, of the original morphology of the apical foramen, (AF), so that the filling material will form a complete seal.

METHODS

In our previous studies, in order to verify if this presumption was respected using rotary NiTi instruments with cutting tip, we instrumented extracted teeth characterised by a different degree of root curvatures. Using a standardized system to replace the sample, the original shape of the apical foramen of each tooth was recorded using a computerised technique and then compared to the shape after instrumentation. The data showed differences on AF shapes depending on the degree of root canal curvatures. In fact, the teeth with straight canals showed the least alterations on the original AF shape; on the contrary, the teeth with curved canals showed apical foramen enlargement or transportation. Therefore, in the current study we aimed to compare the in vitro effects of stainless steel, (Flexofile, Dentsply Maillefer, Baillaigues, Switzerland), vs NiTi safe cutting tip (Quantec SC, (Tycom Dental, Irvine CA, U:S.A.), vs NiTi non cutting tip, (Quantec LX, Tycom Dental, Irvine CA, U:S.A.), instrumentation on original apical foramen shape. We used NiTi instruments according to standard technique suggested by Tycom, and hand steel files, to instrument the apical third, according to the Crown-Down technique. Working length was fixed at -0.5 from AF.

RESULTS AND CONCLUSIONS

Our results suggested that in the presence of accentuated canal curves rotary Niti, with cutting tip, cause significantly more enlargement of the AF area. At the same time, we also observed that NiTi rotary files, with both cutting and non-cutting tip, cause eccentric enlargement of AF in curved canals. Therefore, NiTi engine-driven instruments should be used carefully in the presence of accentuated canal curves to avoid enlargement or transportation of AF, probably because rotary NiTi files may slip out of operative control, leaving a mark on the foramen shape. In the presence of severe curves, we suggest modifying the operative sequences by alternating rotary NiTi with hand NiTi or stainless steel instruments, especially in the preparation of apical third.