Akonni Biosystems: Wicking in Microchannels on Biochips

Microfluidics is the science of designing and manufacturing devices and processes for manipulation of extremely small volumes of fluid, typically micro to nanoliters.The most mature application of microfluidics technology is ink-jet printing, which uses orifices less than 100 μm in diameter to generate drops of ink. The complex devices now being developed for biological applications involving the analysis of DNA (in genetics and genomics) and proteins (in proteomics) and bio-defense typically involve aqueous solutions and channels 30 to 300 μm in diameter. Unlike microelectronics, in which the current emphasis is on reducing the size of transistors, microfluidics is focusing on making more complex systems of channels with more sophisticated fluid-handling capabilities, rather than reducing the size of the channels. Although micro- and macro-fluidic systems require similar components including pumps, valves, mixers, filters, and separators, the small size of microchannels causes their flow to behave differently. At micron scales, fluid motions are primarily dominated by surface tension and viscous forces. In the problem under consideration, the issue is one of wicking or leaking of the sample from the reaction reservoir to the waste region at elevated temperatures. A mechanism responsible for this phenomenon was thought to be the "wedge effect," which refers to the tendency of liquids to move along a sharp corner by capillary effects if the conditions are right. The analysis performed during the workshop also mainly focused on this effect. While a definitive solution to this challenging problem posed in the workshop was not identified, it was felt that using a manufacturing process that can affect the corner angles in the channels may hold the most promise, allowing the wicking mechanism to be controlled without surface treatments that insert hydrophobic stops in the channel. For instance by "rounding" the side walls to increase the corner angles from 90 toward 180 degrees, the leaking of the sample away from the reaction chamber might be delayed

Zimmermann-Laband syndrome : clinical and cytogenetic study in two related patients

Zimmermann?Laband Syndrome (ZLS) is an extremely rare autosomal dominant congenital disorder. It is a craniofacial malformation syndrome with predominant intraoral involvement consisting of gingival fibromatosis diffusion in early development. The molecular basis of ZLS is still unknown. Although familial aggregation with different inheritance patterns is detected in ZLS patients, most of the cases are sporadic. We report on two sibling patients with clinical manifestations of ZLS. Blood samples of both patients were obtained in EDTA-tubes followed by performing cytogenetic study using Cyto2.7M array. Analysis of the copy number was performed using the Chromosome Analysis Suite Software (version 1.0.1, annotation file na 30, Affymetrix) and interpreted with recourse to the UCSC genome browser (http://genome.ucsc.edu/; Human Mar. 2006NCBI Build 36.1/hg18 assembly). The array analysis revealed overlapping regions of chromosomal aberrations in both patients. We detected a 258-kb deletion at 3q13.13, a 89-kb duplication at 1q25.2 as well as two 67-kb duplications at 1p12 and 19q12. These altered regions do not contain any known genes and protein-coding sequences. In conclusion, the findings of this report revealed new chromosomal aberrations, including a deletion at 3q13.13 and duplications at 1q25.2, 1p12 and 19q12, in the two patients with ZLS. Such findings indicate that whole genome screening for genomic rearrangements is fruitful in typical and atypical patients with ZLS

Problem of Foreign Body in GI Tract

Most foreign bodies pass through the gastrointestinal tract uneventful. We report of a case of inadvertently ingested foreign body, which by endoscopy simulated a polyp and on biopsy reported as cancer, so the patient underwent an unnecessary major operation. This report emphasizes the importance of resemblance of foreign bodies with gastrointestinal neoplasm, and endoscopists, surgeons and pathologists should consider this entity in their daily practice

Discrepancy of target sites between clinician and cytopathological reports in head neck fine needle aspiration: Did I miss the target or did the clinician mistake the organ site?

The diagnostic accuracy of fine needle aspiration cytology (FNAC) of head and neck lesions is relatively high, but cytologic interpretation might be confusing if the sample is lacking typical cytologic features according to labeled site by physician. These errors may have an impact on pathology search engines, healthcare costs or even adverse outcomes. The cytology archive database of multiple institutions in southern Iran and Australia covering the period 2001–2011, were searched using keywords: salivary gland, head, neck, FNAC, and cytology. All the extracted reports were reviewed. The reports which showed discordance between the clinician’s impression of the organ involved and subsequent fine needle biopsy request, and the eventual cytological diagnosis were selected. The cytological diagnosis was confirmed by histology or cell block, with assistance from imaging, clinical outcome, physical examination, molecular studies, or microbiological culture. The total number of 10,200 head and neck superficial FNAC were included in the study, from which 48 cases showed discordance between the clinicians request and the actual site of pathology. Apart from the histopathology, the imaging, clinical history, physical examination, immunohistochemical study, microbiologic culture and molecular testing helped to finalize the target organ of pathology in 23, 6, 7, 8, 2, and 1 cases respectively. The commonest discrepancies were for FNAC of “salivary gland” [total: 20 with actual final pathology in: bone (7), soft tissue (5), lymph node (3), odontogenic (3) and skin (2)], “lymph node” [total: 12 with final pathology in: soft tissue (3), skin (3), bone (1) and brain (1)], “soft tissue” [total: 11 with final pathology in: bone (5), skin (2), salivary gland (1), and ocular region (1)] and “skin” [total: 5 with final pathology in: lymph node (2), bone (1), soft tissue (1) and salivary gland (1)]. The primary physician requesting FNAC of head and neck lesions are incorrect in their clinical impression of the actual site in nearly 0.5 percent of cases, due to the overlapping clinical and imaging findings or possibly due to inadequate history taking or physical examination

Is Helicobacter pylori infection a risk factor for childhood periodic syndromes?

AbstractBackground and objectivesHelicobacter pylori (H. pylori) infection has been assumed to have roles in various extra-digestive diseases. The current study was designed to evaluate the incidence of H. pylori infection in patients with cyclic vomiting syndrome and its possible role in the etiology of this disease.Design and settingIn this case-control study, 120 cases with diagnoses of cyclic vomiting or abdominal migraine who were registered at the Gastroenterology Clinic at Shiraz University of Medical Sciences from 2010 to 2013 were enrolled.Materials and methodsPrimarily information regarding the patients' diseases were collected with a data gathering sheet, and fresh morning stool samples were collected from the patients and examined for H. pylori stool antigen with the H. pylori Ag EIA test kit. The results were compared with those of healthy children from the control group.ResultsA total of 120 patients with cyclic vomiting (47.5%) and abdominal migraine (52.5%) with a mean age of 7.1 ± 3.4 (range 2–16 years) and a male-to-female ratio of 1.6 were included. The HPs Ag tests were positive in only 7 (5.8%) patients in our case group, and the HPs Ag tests were positive in 13 (13%) of the children in the control group; this difference was statistically insignificant.ConclusionOur study did not support H. pylori infection as an etiological factor in CV or AM

The Best in CytoJournal: 2005

CytoJournal opened its doors in late 2004 and 2005 was the first full year of publication. In order to celebrate this event as well as recognize the contributing authors works, CytoJournal has initiated a Best Article of the Year, in this case 2005. This year's Best of CytoJournal: 2005 is an excellent review of thyroid FNAB

Inflammation and structural changes of splenic lymphoid tissue in visceral leishmaniasis: A study on naturally infected dogs

The aim of this study was to identify splenic immuno-inflammatory patterns associated with natural infection by Leishmania chagasi. Spleen samples were obtained from 72 stray dogs from an endemic area of visceral leishmaniasis. The animals were grouped into four categories as follows: (i) potentially resistant to visceral leishmaniasis, with a positive leishmanin skin test result, and negative splenic culture for Leishmania parasites (ii) potentially susceptible to visceral leishmaniasis, with a negative leishmanin skin test and positive splenic culture for Leishmania (iii) infected with undefined susceptibility status, with a positive leishmanin skin test and positive splenic culture for Leishmania, and (iv) noninfected, with a negative leishmanin skin test, negative splenic culture for Leishmania, and negative serology for anti-Leishmania antibodies. Histopathological analyses showed that there was a higher frequency of perisplenitis (18/25, P < 0·0001), granuloma (7/25, P = 0·0102), structural disorganization (14/25, P < 0·0001), and atrophy of the lymphoid follicles (20/25, P = 0·0036) and of the marginal zone (15/25, P = 0·0025) in the potentially susceptible group than in the other groups. The data presented here show changes in the white pulp of the spleen that are associated with naturally acquired visceral leishmaniasis