Evaluation of Portability and Cost of a Fluorescent PCR Ribotyping Protocol for Clostridium difficile Epidemiology

Clostridium difficile is the most commonly identified pathogen among health care-associated infections in the United States. There is a need for accurate and low-cost typing tools that produce comparable data across studies (i.e., portable data) to help characterize isolates during epidemiologic investigations of C. difficile outbreaks and sporadic cases of disease. The most popular C. difficile-typing technique is PCR ribotyping, and we previously developed methods using fluorescent PCR primers and amplicon sizing on a Sanger-style sequencer to generate fluorescent PCR ribotyping data. This technique has been used to characterize tens of thousands of C. difficile isolates from cases of disease. Here, we present validation of a protocol for the cost-effective generation of fluorescent PCR ribotyping data. A key component of this protocol is the ability to accurately identify PCR ribotypes against an online database (http://walklab.rcg.montana.edu) at no cost. We present results from a blinded multicenter study to address data portability across four different laboratories and three different sequencing centers. Our standardized protocol and centralized database for typing of C. difficile pathogens will increase comparability between studies so that important epidemiologic linkages between cases of disease and patterns of emergence can be rapidly identified.     

Screw and Wire Technique for Condylar Fracture Reduction

In case of displaced condylar fractures, ideal reduction during open reduction and internal fixation poses a challenge to the surgeon. This article describes a simple technique to aid reduction with the use of a screw and wire during open treatment.     

Normal saline-induced deoxygenation of red blood cells probed by optical tweezers combined with the micro-Raman technique

The use of normal saline for washing red blood cells and treating critically ill patients is a regular medical practice in hospital settings. An optical tweezer in combination with Raman spectroscopy is an analytical tool employed for the investigation of single cell dynamics, thus providing molecular fingerprint of the cell by optically trapping the cell at a laser focus. In this study, the impact of normal saline on individual human red blood cell was compared with that of blood plasma using Raman tweezers spectroscopy. Major spectral variations in the marker frequencies at 1209 cm⁻¹, 1222 cm⁻¹, 1544 cm⁻¹, and 1561 cm⁻¹ of the Raman spectrum of the treated cells imply that the transition of hemoglobin to the deoxygenated state occurs when 0.9% normal saline is used. This may result in serious implications in blood transfusion. The results obtained from the principal component analysis also displayed clear differentiation among the red blood cells diluted in normal saline and those diluted in plasma. In future studies, efforts will be made to correlate the deoxygenation status of red blood cells with various human disorders.

Micro-Raman spectroscopy of optically trapped live red blood cell demonstrates normal saline induced deoxygenation.     

Post annealing induced manipulation of phase and upconversion luminescence of Cr3+ doped NaYF4:Yb,Er crystals

The role of post synthesis annealing at different temperatures (200–600 °C) on the structural as well as luminescence properties of NaY_80%F₄:Yb_17%,Er_3% prepared via a coprecipitation method was found to change the structure from a cubic to hexagonal phase with a concomitant increase in upconversion luminescence by 12 times for the green region and 17 times for the red region. Addition of the Cr³⁺ ions (5–20 mol%) into the host followed by post annealing at 200–600 °C causes that the samples to exhibit phase dependent and upconversion luminescence behavior that depend upon the doping concentration as well as the annealing temperature. The inductively coupled optical emission spectroscopy reveals that only 1/600 times of the desired volume of the co-dopant goes to the lattice and it can manifest visible spectral changes in the diffuse reflectance spectra of the samples. The samples co-doped with Cr³⁺ ion concentrations of 10–15% and post-annealed at 600 °C were found to have maximum emission with an enhancement factor of 24 for the green region and 33 for the red region. In addition, the laser power dependent studies reveal that even for the power density levels 3.69 W cm⁻² to 32.14 W cm⁻², the samples are in the saturation regime and most of the samples investigated here follow a single photon process, and a few samples show a slope value less than 1 for laser power dependent intensity plots. The results show the remarkable promise of controlled tailoring of the properties of upconversion crystals via post annealing and co-doping.

Co-dopant (Cr³⁺ ion) concentration as well as post annealing found to change the structural as well as luminescence properties of Cr³⁺ ion doped NaY_80%F₄:Yb_17%,Er_3% prepared via a co-precipitation method.     

Oral Cancer in India: An Epidemiologic and Clinical Review

Oral cancer is one of the most fatal health problems faced by the mankind today. In India, because of cultural, ethnic, geographic factors and the popularity of addictive habits, the frequency of oral cancer is high. It ranks number one in terms of incidence among men and third among women. Several factors like tobacco and tobacco related products, alcohol, genetic predisposition and hormonal factors are suspected as possible causative factors. Hence the study was designed to determine the prevalence of Oral Cancer in patients who attended the outpatient department, at Bharati Vidyapeeth Deemed University Dental College Sangli India during a period of 24 months in 2009–2010. Further various modes of tobacco and alcohol consuming habit were assessed along with the site of occurrence of oral cancer. About 35,122 subjects belonging to a semi-urban district of Sangli in Western Maharashtra (India) were screened. Tobacco and alcohol consumption was the common habit among the study population. Out of these about 112 cases showed Oral Cancer. The prevalence of Oral Cancer was 1.12%. Statistical analysis was done using the SPSS software 11. The findings in the present study reveal a high prevalence of Oral Cancer and a rampant misuse of variety of addictive substances in the community. Close follow up and systematic evaluation is required in this population. Education about ill effects of tobacco and alcohol consumption is necessary at a broader scale. There is an urgent need for awareness programs involving the community health workers, dentists and allied medical professionals.     

Sickle cell patient with an acute chest syndrome and a negative chest X-ray: potential role of the ventilation and perfusion (V/Q) lung scan

Acute chest syndrome (ACS) in sickle cell disease is caused by thromboemboli in the pulmonary vasculature. The diagnostic criteria include the presence of pulmonary infiltrate(s) on chest x-ray. This case report suggests that a V/Q scan may play a diagnostic role in sickle cell patients with symptoms of ACS and a negative chest x-ray.     

Brugada syndrome

Two siblings with features of Brugada syndrome are reported. One of them had permanent pacemaker implantation elsewhere where he was evaluated for recurrent syncope and diagnosed to have tri-fascicular block. He continued to have syncopal episodes and subsequently detected to have runs of polymorphic ventricular tachycardia picked up on a routine ECG. His sibling also was found to have features of Brugada syndrome.     

Vascular changes and black hole phenomenon after coronary brachytherapy: a pathologically distinct entity

Restenosis remains an important issue even after coronary brachytherapy despite its efficacy in the treatment for in-stent restenosis. The acute and chronic changes in vascular wall are unique following brachytherapy. The restenotic tissue post coronary brachytherapy is relatively acellular and appears echolucent in intravascular ultrasound examination. This is dubbed the "black hole" phenomenon. Despite the similarity in the mode of action of brachytherapy and drug eluting stent implantation, the black hole phenomenon seems to be uncommon after drug-eluting stent implantation except in those patients who have had prior brachytherapy, bare-metal placement and after treatment of saphenous venous graft stenosis. It is possible that not all neointima in stents are created equal. We should propose that neointima be considered primary neointima if it forms after bare metal stenting, secondary neointima if it forms after CBT or DES, and perhaps tertiary if after combined CBT and DES. This type of classification may prove useful for research or clinical purposes. Almost certainly black hole phenomenon results from a modified neointima. However, we do not know whether this is the same restenotic tissue that was present before CBT but just depleted of its cellular element secondary to autolysis or a newly formed tertiary neointima? It is also not clear whether the changes in vascular wall and restenosis are similar after CBT or drug-eluting stent placement. However, there are some unique vascular changes that seem to be common after both of these procedures.