Biomedical Laboratory Science

Friday, April 29, 2016

Esophageal Cancer

Overview

Esophageal cancer starts at the inside lining of the esophagus and spreads outward through the other layers as it grows. The two most common forms of esophageal cancer are named for the type of cells that become malignant:

Squamous cell carcinoma: Cancer that forms in squamous cells, the thin, flat cells lining the esophagus. This cancer is most often found in the upper and middle part of the esophagus, but can occur anywhere along the esophagus. This is also called epidermoid carcinoma.
Adenocarcinoma: Cancer that begins in glandular (secretory) cells. Glandular cells in the lining of the esophagus produce and release fluids such as mucus. Adenocarcinomas usually form in the lower part of the esophagus, near the stomach.

The National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) Program estimates that some 16,980 people in the United States will be diagnosed with esophageal cancer and 15,590 will die of the disease in 2015. The average five year survival rate is just 17.9 percent.

Smoking, heavy alcohol consumption, and Barrett esophagus can increase the risk of developing esophageal cancer. Other risk factors include older age, being male, and being African-American.

Islet transplantation, blood sugar and type 1 diabetes

New clinical trial results show that transplantation of pancreatic islets--cell clusters that contain insulin-producing cells--prevents severe, potentially life-threatening drops in blood sugar in people with type 1 diabetes. Researchers found that the treatment was effective for people who experienced episodes of severe hypoglycemia--low blood sugar levels that can lead to seizures, loss of consciousness and death--despite receiving expert care.

The Phase 3 trial was funded by the National Institute of Allergy and Infectious Diseases (NIAID) and the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), both part of the National Institutes of Health, and was conducted by the NIH-sponsored Clinical Islet Transplantation (CIT) Consortium. The investigators designed the study in consultation with the U.S. Food and Drug Administration to enable potential future licensure of the manufacture of purified human pancreatic islets. The results appear online today in Diabetes Care.

"The findings suggest that for people who continue to have life-altering severe hypoglycemia despite optimal medical management, islet transplantation offers a potentially lifesaving treatment that in the majority of cases eliminates severe hypoglycemic events while conferring excellent control of blood sugar," said NIAID Director Anthony S. Fauci, M.D.

Transplantation of pancreatic islets--cell clusters that contain insulin-producing cells--prevents severe,
potentially life-threatening drops in blood sugar in people with type 1 diabetes, according to new research

Source: ibreakstock/Fotolia

Obesity, stress and even cellphone use can influence men's ability to conceive

Certain lifestyle factors are linked to higher rates of damage in the genetic material in men’s sperm. This could affect men’s ability to conceive as well as the genes they pass on to their children.

According to researchers, the damage may stem from factors such as obesity, stress and even cellphone use.

Semen analysis usually looks at the numbers and the condition of whole sperm. But the authors of a small study in Poland believe the degree of breakage, or fragmentation, in DNA strands in the sperm might be a better indicator of fertility. DNA carries the cell’s genetic information and hereditary characteristics.

Men with fragmentation have lower odds of conceiving naturally and through such procedures as in vitro fertilization, the scientists write in the International Journal of Impotence Research.

Researchers have noticed before that lifestyle factors can influence the level of sperm DNA fragmentation, said Ricardo P. Bertolla of Sao Paulo Federal University in Brazil, who was not part of the new study.

In a new study, older men and those with higher work stress had more fragmentation of the DNA in
their sperm, which might affect their ability to conceive as well as the genes they pass on to their children.

Source: De Agostini/Getty Images

Biosafety Levels 1, 2, 3 & 4

Biological safety levels are ranked from one to four and are selected based on the agents or organisms on which the research or work is being conducted. Each level up builds on the previous level, adding constraints and barriers.

Biological Agents, Work Practices, Safety Equipment, and Facility Design Specific to Each

A very specialized research laboratory that deals with infectious agents is the biosafety lab. Whether performing research or production activities, when working with infectious materials, organisms or perhaps even laboratory animals, the proper degree of protection is of utmost importance. Protection for laboratory personnel, the environment and the local community must be considered and ensured. The protections required by these types of activities are defined as biosafety levels. Biological safety levels are ranked from one to four and are selected based on the agents or organisms on which the research or work is being conducted. Each level up builds on the previous level, adding constraints and barriers. The Centers for Disease Control and Prevention (CDC) and the National Institutes of Health (NIH) are our main sources for biological safety information for infectious agents. The publication Biosafety in Microbiological and Biomedical Laboratories1 is a principal reference and the resource for much of the information presented in this month’s column. As an introduction, we summarize what the different biosafety levels encompass in terms of the typical biological agents used, safe work practices, specialized safety equipment (primary barriers) and facility design (secondary barriers).

The Brain-to-Brain Loop in Molecular Oncology Laboratory Testing

Various Methods Allow Clinical Laboratories to Maximize Their Efficiency and Usefulness

The delineation of a brain-to-brain loop in clinical laboratory testing first published in 1981 has never been more pertinent. Its subsequent development and current application in clinical molecular oncology in 2016 can make all the difference.

This discussion focuses on the factors that drive the ordering of a lab test and the many components thereof, itemizes pre- and post-analytic causes of diagnostic error, and recommends how a laboratory can help ensure the usefulness of the entire process.

Just as a chain is no stronger than its weakest link, a loop that isn’t closed is (obviously) still open.

Technical and laboratory workers tend naturally to define their work by their technical products and procedures, as well they should. In clinical laboratory testing, that tends to be the step called “analysis.”

The success or failure of an “analysis” may well depend upon the pre- and post-analytic phases at least as much as the analysis itself.

Source: DepositPhotos

PCR-Free Novel Genome Sequencing Technology

Will Nanopore Sequencing Make it Obsolete?

Genome sequencers have been tweaking polymerase chain reaction (PCR) amplification to avoid introducing artifacts into sequencing libraries, ranging from modifications in chemistries to the introduction of novel sequencing technologies that could obviate the need for PCR altogether.

PCR-related problems have included uneven amplification, causing overrepresentation of some sequence species and nucleotide misincorporation. In particular, sequencing genomes or genomic regions with extremely biased base composition remains a challenge to the currently available next-generation sequencing (NGS) platforms. These include, for example, the genomes of important pathogenic organisms like Plasmodium falciparum with a high adenine–thymine (AT) content and Mycobacterium tuberculosis with high guanine–cytosine (GC) content.

These genomes have proven difficult for sequencers because the standard library preparation procedures that employ PCR amplification cause uneven read coverage across these regions, leading to problems in genome assembly and variation analyses.

Disruptive sequencing based on nanopore technology has the potential to change
completely the way DNA sequencing is done.

Source: beawolf/Fotolia

Thursday, April 28, 2016

Sticky beads binding to sperm could offer a novel contraceptive

You ain't going nowhere.

We might have a brand new type of contraceptive on our hands, with scientists inventing sticky beads that can mimic female eggs in the uterus, and act as decoys to lure in sperm, bind to them, and block them from reaching the real thing.

The beads, which have so far only been tested in mice, do their thing thanks to a protein called ZP2, which exists on the zona pellucida – the surface of mammalian eggs. During conception, a sperm cell recognises a molecular fragment of ZP2 and binds to it, enabling the egg to be penetrated and fertilised. By mimicking this process with inert beads coated in the same protein, the sticky beads are effectively a honey pot to trap unwitting sperm.

In the study, a team from the US National Institute of Diabetes and Digestive and Kidney Diseases embedded the sticky beads into the uterus of female mice.

Source: ScienceAlert

Complete Blood Count in Primary Care

Key points

To provide an overview of the use of the complete blood count in primary care and to provide advice on appropriate follow-up for abnormal results.

Introduction

The complete blood count (CBC) is the most frequently requested blood test in New Zealand. The primary points of interest in the CBC are often whether a patient is anaemic, whether the white count shows evidence of infection and whether the platelets are at a level that may affect haemostasis.

GPs have told us they are reasonably comfortable interpreting CBC results with marked abnormalities, but would like guidance when the results show only subtle abnormalities or when the clinical picture is not clear.

This is a consensus document

This is not a comprehensive document covering all causes of abnormal results; it is a consensus document produced in conjunction with specialist haematologists, providing an overview for some scenarios encountered in primary care.

Background

Haematopoiesis - Cell development

All blood cells are produced within the bone marrow from a small population of stem cells. Less than one in 5000 of the marrow cells is a stem cell. These cells represent a self-renewing population.

Download here: Complete Blood Count in Primary Care

Source: Best Practice Advocacy Centre New Zealand

Virus attacks hospital's medical laboratory department computers

Virus Attacks Hospital’s Medical Laboratory Department Computers, Crippling Workflow and Spreading to Other Departments

Incident highlights need for anatomic pathology and clinical laboratories to protect computer and LIS systems from hackers and malware

Anatomic pathology labs and clinical laboratories that continue to run Microsoft Windows XP on their computer systems now have a real threat to address. In Australia, the computers in a hospital’s medical laboratory were infected in January with a computer virus that shut down the system. To maintain clinical services, the lab staff was forced to use paper-based methods, among other solutions.

The computer virus crippled the pathology department at the Royal Melbourne Hospital and spread throughout the hospital system by targeting computers running Microsoft Windows XP. This is a 14-year-old operating system that Microsoft no longer supports.

Source: WorldCrunch/CloudTimes

Molecular Diagnostics in the Microbiology Laboratory

A look at some of the newest generation ‘load and go’ molecular microbiology analyzers.

For decades, pathogens have been isolated and grown in blood cultures, and detected using microscopes, serology and biochemical techniques. However the last few years have seen a revolution in modern microbiology.

The above tests still form the core work of most routine microbiology labs, but modern analytical techniques such as molecular diagnostics and mass spectrometry are increasingly being incorporated, to varying degrees, in laboratories around the world.

Molecular diagnostics refers to the analysis of nucleic acid from DNA or RNA. In the clinical microbiology lab, scientists are looking for the nucleic acid of microorganisms to confirm or exclude a diagnosis.

The molecular diagnostic work undertaken in the lab can vary from a simple, manual monoplex polymerase chain reaction (PCR) based test to complex automated, multiplex testing (testing for multiple pathogens simultaneously). Some of the newest generation ‘load and go’ molecular analyzers are detailed below.

VERIS Mdx Molecular Diagnostics System

The DxN VERIS combines sample prep and sample analysis steps into a single workflow. The automation of DNA extraction, purification, assay set-up and analysis saves the user time and also prevents user error and the risk of contamination. Using real-time PCR, the system is designed for multiplex assays and uses magnetic particle separation for nucleic acid extraction and purification. The initial test menu includes Cytomegalovirus, Hepatitis B, Hepatitis C and HIV-1 ......

Microbiology has traditionally involved use of blood cultures, however molecular methods are
increasingly employed in modern laboratories;
Beckman Coulter's VERIS Mdx Molecular Diagnostics System

Source: SelectScience

Biomedical Laboratory Science