Biofilm as an adaptation strategy to extreme conditions

Biofilm is the most successful and widely distributed form of life on earth, it is not simply structured collections of cells attached to surfaces but is a dynamic complex biological system able to respond to environmental changes. The biofilm characteristics make it unique and central to microbial evolution and adaptation. The ability to establish biofilms is a key trait for microorganisms growing in extreme environments like extreme temperature, high radiation, acidic or alkaline pH values, heavy metal pollution, and high salinity. In this article, we report the main features of biofilm and how these characteristics make biofilms a successful survival strategy in extreme conditions. All aspects examined in this article help to explain why biofilms are a successful survival strategy in extreme conditions and why the ability to establish biofilms is a key trait for microorganisms growing in extreme environments

Active human full-length CDKL5 produced in the Antarctic bacterium Pseudoalteromonas haloplanktis TAC125

Background: A significant fraction of the human proteome is still inaccessible to in vitro studies since the recombinant production of several proteins failed in conventional cell factories. Eukaryotic protein kinases are difficult-to-express in heterologous hosts due to folding issues both related to their catalytic and regulatory domains. Human CDKL5 belongs to this category. It is a serine/threonine protein kinase whose mutations are involved in CDKL5 Deficiency Disorder (CDD), a severe neurodevelopmental pathology still lacking a therapeutic intervention. The lack of successful CDKL5 manufacture hampered the exploitation of the otherwise highly promising enzyme replacement therapy. As almost two-thirds of the enzyme sequence is predicted to be intrinsically disordered, the recombinant product is either subjected to a massive proteolytic attack by host-encoded proteases or tends to form aggregates. Therefore, the use of an unconventional expression system can constitute a valid alternative to solve these issues. Results: Using a multiparametric approach we managed to optimize the transcription of the CDKL5 gene and the synthesis of the recombinant protein in the Antarctic bacterium Pseudoalteromonas haloplanktis TAC125 applying a bicistronic expression strategy, whose generalization for recombinant expression in the cold has been here confirmed with the use of a fluorescent reporter. The recombinant protein largely accumulated as a full-length product in the soluble cell lysate. We also demonstrated for the first time that full-length CDKL5 produced in Antarctic bacteria is catalytically active by using two independent assays, making feasible its recovery in native conditions from bacterial lysates as an active product, a result unmet in other bacteria so far. Finally, the setup of an in cellulo kinase assay allowed us to measure the impact of several CDD missense mutations on the kinase activity, providing new information towards a better understanding of CDD pathophysiology. Conclusions: Collectively, our data indicate that P. haloplanktis TAC125 can be a valuable platform for both the preparation of soluble active human CDKL5 and the study of structural–functional relationships in wild type and mutant CDKL5 forms. Furthermore, this paper further confirms the more general potentialities of exploitation of Antarctic bacteria to produce “intractable” proteins, especially those containing large intrinsically disordered regions

Laparoscopic ileocecal resection in acute and chronic presentations of Crohn's disease. A single center experience

The terminal ileum is the most involved tract in Crohn's disease. The obstruction in this location is the most frequent complication. Acute or chronic presentations can occur. Surgery finds a role in the management of chronic strictures and in acute clinical presentations with complications not improving with conservative therapy

Rectal bleeding and prolapse\u2026 not always benign diseases rather anal cancer. The importance of a correct decision making since primary care

Rectal bleeding is very common in general population with a prevalence of 10-20 %. Primary care physicians have to stratify patients basing on urgency and on the colo-rectal cancer risk and to conduct a decision making for the correct management. We report a case of a 61-years-old woman, complaining rectal bleeding and an anal mass attended to their family doctor who does a visit but without a digital rectal examination and diagnosed a hemorrhoidal prolapse suggesting medical therapy. For the persistence of symptoms she comes to our service from emergency attention. Inspection and digital rectal examination revealed an anal mass. CT scan was performed showing a large anal mass involving half anal circumference. Histologic samples showed an epithelial proliferation compatible with a squamous carcinoma. Oncological consult was requested and a chemo-radiotherapy treatment was proposed. This case report highlights the difficulty when physicians assess patients with anorectal complaints in differentiating anal cancer from benign disease, presumably because symptoms are similar. Primary care physicians must maintain a high index of suspicion of cancer in high-risk population. Sensitization of these colleagues is required since digital rectal examination is of inestimable value to verify the presence of a rectal or an anal mass.Abstract Rectal bleeding is very common in general population with a prevalence of 10-20 %. Primary care physicians have to stratify patients basing on urgency and on the colo-rectal cancer risk and to conduct a decision making for the correct management. We report a case of a 61- years-old woman, complaining rectal bleeding and an anal mass attended to their family doctor who does a visit but without a digital rectal examination and diagnosed a hemorrhoidal prolapse suggesting medical therapy. For the persistence of symptoms she comes to our service from emergency attention. Inspection and digital rectal examination revealed an anal mass. CT scan was performed showing a large anal mass involving half anal circumference. Histologic samples showed an epithelial proliferation compatible with a squamous carcinoma. Oncological consult was requested and a chemo-radiotherapy treatment was proposed. This case report highlights the difficulty when physicians assess patients with anorectal complaints in differentiating anal cancer from benign disease, presumably because symptoms are similar. Primary care physicians must maintain a high index of suspicion of cancer in high-risk population. Sensitization of these colleagues is required since digital rectal examination is of inestimable value to verify the presence of a rectal or an anal mass. \ua9 2016, CIC Edizioni Internazionali, Roma

Mannheim Peritonitis Index (MPI) and elderly population: Prognostic evaluation in acute secondary peritonitis

Introduction. Acute Secondary Peritonitis due to abdominal visceral perforation is characterized by high mortality and morbidity risk. Risk stratification allows prognosis prediction to adopt the best surgical treatment and clinical care support therapy. In Western countries elderly people represent a significant percentage of population Aim. Evaluation of Mannheim Peritonitis Index (MPI) and consideration upon old people. Patients and methods. Retrospective study on 104 patients admitted and operated for \ue2\u80\u9cAcute Secondary Peritonitis due to visceral perforation\ue2\u80\u9d. MPI was scored. In our study we want to demonstrate efficacy of MPI and the possibility to consider older age an independent prognostic factor. Results. Mortality was 25.96%. Greatest sensitivity and specificity for the MPI score as a predictor of mortality was at the score of 20. MPI score of 22. Patients with MPI score 17-21 had 0.46 times lower risk of mortality compared to patients with MPI score >21. In the group of patients with MPI score of >20 the mortality rate was 48.5% for patients older than 80 years old and 12.1% for younger patients (p < 0.005); in the group with MPI score of < 20 mortality rate was respectively 8.4% and 1.4% (p < 0.005). Discussion and conclusions. Data confirm the accuracy of the test. MPI score and age over 80 years old resulted independent predictors of mortality at multivariate analysis

Development of high-copy number plasmids in Pseudoalteromonas haloplanktis TAC125

Abstract: The Antarctic bacterium Pseudoalteromonas haloplanktis TAC125 (PhTAC125) is considered an interesting alternative host for the recombinant protein production, that can be explored when the conventional bacterial expression systems fail. Indeed, the manufacture of all the difficult-to-express proteins produced so far in this bacterial platform gave back soluble and active products. Despite these promising results, the low yield of recombinant protein production achieved is hampering the wider and industrial exploitation of this psychrophilic cell factory. All the expression plasmids developed so far in PhTAC125 are based on the origin of replication of the endogenous pMtBL plasmid and are maintained at a very low copy number. In this work, we set up an experimental strategy to select mutated OriR sequences endowed with the ability to establish recombinant plasmids at higher multiplicity per cell. The solution to this major production bottleneck was achieved by the construction of a library of psychrophilic vectors, each containing a randomly mutated version of pMtBL OriR, and its screening by fluorescence-activated cell sorting (FACS). The selected clones allowed the identification of mutated OriR sequences effective in enhancing the plasmid copy number of approximately two orders of magnitude, and the production of the recombinant green fluorescent protein was increased up to twenty times approximately. Moreover, the molecular characterization of the different mutant OriR sequences allowed us to suggest some preliminary clues on the pMtBL replication mechanism that deserve to be further investigated in the future. Key points: • Setup of an electroporation procedure for Pseudoalteromonas haloplanktis TAC125. • Two order of magnitude improvement of OriR-derived psychrophilic expression systems. • Almost twenty times enhancement in Green fluorescent protein production

Is it really useful the harmonic scalpel in axillary dissection for locally advanced breast cancer? A case series

Background. The seroma is one of the most common complications in the axillary lymph nodal dissection (different surgical approaches have been tried to reduce the seroma incidence). In our study we evaluate the outcome of patients using or not the ultrasonic scalpel (Harmonic scalpel) according to a standardized surgical technique. Patients and Methods. From January 2011 to December 2015 120 patients underwent axillary dissection for breast cancer. Patients were divided in two groups: patients belonging to the first group underwent Harmonic scalpel dissection and patients belonging to the second group underwent classical dissection. Each group consisted of 60 patients. Quadrantectomy (QUAD) was performed in 54 patients, 66 women underwent mastectomy. In all patients axillary dissection included the I, II and III level. We compared two groups in terms of: time of surgery, hematoma, drainage volume, days of sealing drainage, seroma formation, number of post-seroma aspirations, upper limb lymphedema, wound infections, post-operative pain. Results. Statistically significant results were obtained in terms of the total volume of the breast and axillary drainage in the two techniques. There were no significant differences in the two samples in terms of operative time incidence of seroma, post-operative hematoma, wound infection, and lymphedema of the upper limb. Conclusion. The small number of cases did not allow us to reach definitive conclusions. The use of Harmonic scalpel seems to show smaller incidence of seroma and reduction of the amount of both breast and axillary drainages. Further studies are needed to define the real advantage in terms of cost benefit of using these devices in the axillary surgery