Development of liver microtissues with functional biliary ductular network.

Liver tissue engineering aims to create transplantable liver grafts that can serve as substitutes for donor's livers. One major challenge in creating a fully functional liver tissue has been to recreate the biliary drainage in an engineered liver construct through integration of bile canaliculi (BC) with the biliary ductular network that would enable the clearance of bile from the hepatocytes to the host duodenum. In this study, we show the formation of such a hepatic microtissue by coculturing rat primary hepatocytes with cholangiocytes and stromal cells. Our results indicate that within the spheroids, hepatocytes maintained viability and function for up to 7 days. Viable hepatocytes became polarized by forming BC with the presence of tight junctions. Morphologically, hepatocytes formed the core of the spheroids, while cholangiocytes resided at the periphery forming a monolayer microcysts and tubular structures extending outward. The spheroids were subsequently cultured in clusters to create a higher order ductular network resembling hepatic lobule. The cholangiocytes formed functional biliary ductular channels in between hepatic spheroids that were able to collect, transport, and secrete bile. Our results constitute the first step to recreate hepatic building blocks with biliary drainage for repopulating the whole liver scaffolds to be used as transplantable liver grafts.

Immunohistochemical Study of Ezrin Expression in Colorectal Carcinoma: A Comparative Study between Objective Method and Digital Quantitative Assessment.

BACKGROUND: Colorectal cancer is one of the leading causes of cancer death in both developed and developing nations. It is the third most common type of cancer and the fourth leading cause of cancer-related deaths worldwide. Ezrin is involved in maintaining cell structure and cell motility. Expression levels of the ezrin gene correlate with numerous human malignancies. MATERIAL AND METHODS: Ezrin expression was evaluated in fifty one cases of colorectal carcinoma by using two methods; objective and quantitative method to determine the statistical relation between ezrin objective analysis score and clinicopathological parameters and to do a comparative study between both methods of analysis. RESULTS: Ezrin was expressed in 92.2% of cases, and it showed a statistical significant relation with tumor grade. A statistically significant relation was found between ezrin objective analysis score and ezrin quantitative analysis score (P-value <0.05). A strong positive Pearson correlation exists between both methods of analysis (R=0.868). CONCLUSION: Ezrin has a role in colorectal cancer progression and it might provide clinically valuable information in predicting the behavior of colorectal cancer. Digital pathology offers the potential for improvements in quality, efficacy and safety. It will be necessary to carry out similar studies on a larger sample size in order to elucidate the possible prognostic significance of ezrin in colorectal carcinoma and ensure the ability of digital pathology to transform the practice of diagnostic pathology. 
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Prevalence of microscopic colitis in patients with chronic diarrhea in Egypt: a single-center study.

BACKGROUND/AIM: Microscopic colitis (MC) is diagnosed when a patient with chronic watery non-bloody diarrhea (CWND) has an endoscopically normal colon, but colonic biopsies show unique inflammatory changes characteristic of lymphocytic or collagenous colitis. MC is a disorder of unknown etiology. Studies comparing the prevalence of the disease in developing countries as compared to developed countries may shed more light on the possibility of a post-infectious etiology. Most data on the incidence and prevalence of MC are from developed countries where it accounts for 4-13% of cases of CWND. There are only a few reports from developing countries. Two studies from Peru and Tunis, with high prevalence of infectious gastroenteritis, revealed MC in 40% and 29.3% of cases of CWND, respectively. The aim of this study was to investigate the prevalence of MC in patients presenting with CWND in Egypt. MATERIALS AND METHODS: A total of 44 patients with CWND of unexplained etiology who had undergone full colonoscopy with no macroscopic abnormalities between January 2000 and January 2010 were assessed retrospectively. RESULTS: The histological appearance of MC was identified in 22 (50%) patients. Twelve (55%) patients were male and 10 (45%) female. Mean age was 40 years (range: 20-65 years). Twenty (91%) of MC cases had lymphocytic colitis and 2 (9%) had collagenous colitis. CONCLUSIONS: The prevalence of MC in Egyptian patients with CWND is high when compared to that in developed countries. MC mainly affects young and middle-aged patients and it is more commonly of the lymphocytic type.

Acute necrotizing fasciitis in Egyptian patients: a case series.

Hyperacute soft tissue infection is an uncommon infectious entity, which mostly affects immunocompromised individuals, mainly diabetics and poses difficult diagnostic and therapeutic management decisions. This study addresses the presentation, evaluation and management of 37 diabetic patients with acute necrotizing fasciitis treated throughout the period between August 1993 and July 2006 by the main author. Extremities, trunk and perineum were the most commonly involved sites with an incidence of 35%, 30% and 27%, respectively. All patients presented with cellulitis, which was associated with oedema in 75.6% of cases, skin gangrene in 59% of cases and brown ecchymotic patches in 30% of cases. Skin vesicles, tenderness and crepitations were present in 13.5%, 11% and 11% of cases, respectively. Streptococci, Staphylococci and E coli were the most commonly encountered organisms, which affected 70% of cases, either alone or in combination. Anaemia and hypoalbuminaemia were the most commonly encountered laboratory findings in 75.6% and 84% of cases, respectively. The mortality rate in the 37 patients included in this study was 43% (16 cases); in 11 of them the infection was located in the trunk and perineum. Once necrotizing fasciitis is suspected, exploration of the fascia is mandatory with pathological assessment of tissue specimens. Radical debridement of the affected area, maintenance of adequate nutritional support and systemic antibiotic therapy should be implemented at once in order to reduce mortality and insure safe recovery of patients.