Medical Devices and Limulus Amebocyte Lysate (LAL) Testing

The HKIE seminar about LAL testing presented by Ms. Laurie Fife on 13 March 2008 from 4:00pm to 6:00pm in Hong Kong Productivity Council. I would like to summarize and search more information about this topic as follows:

She demonstrates the testing kid to us during the seminar.

Finally, a positive result was obtained.

The pyrogen will cause the elevated body temperature (i.e. fever). Pyrogens are usually bacterial products and remains or decaying products of the bacterial cell walls. Even in minimum dose, these substances induce elevated body temperature when injected into humans and animals. Pyrogens are usually high-molecular-weight substances of polymerous nature, like lipopolysacharids. Pyrogens could be either microbial or non-microbial.

Endotoxins are high-molecular-weight complexes associated with the outer membrane of gram-negative bacteria (GNB). They are the most usual cause of the elevated body temperature, induced by contaminated drug products. Their pyrogenic activity is higher than that of other pyrogenic substances. It could be said that the absence of such bacterial endotoxins in a drug implies the absence of pyrogenic components in examined drug in general. Endotoxins are similar to lipopolysacharids, they are heat stable and can survive the sterilisation process. In their molecular structure, endotoxins contain lipid A which is responsible for the endotoxic activity of the endotoxins. The free form of lipid A, extracted from endotoxins by acid hydrolysis, has almost the same spectrum of biological activities as the endotoxin itself.

Lipopolysaccharide (LPS):
LPS is a major component of the outer membrane of Gram-negative bacteria, contributing greatly to the structural integrity of the bacteria, and protecting the membrane from certain kinds of chemical attack. LPS is an endotoxin, and induces a strong response from normal animal immune systems.

Fever is a rise in our body's normal temperature, which, on average, is 98.6 degrees Farenheit. Our blood and lymphatic systems produce white blood cells which are what fight off infection. As our white blood cells increase in number, like an army to fight the germs, they go faster and faster attacking the germs, this causes our bodies to heat up, thus causing the fever or rise in body temperature. The hypothalamus in the brain, which is the body's heat regulating mechanism is affected by the pyrogens, or the white blood cells that are produced to fight the infection.

Why Limulus Amebocyte Lysate (LAL) testing?
Rabbit Pyrogen Test
1920’s Seibert proved fevers from IV products were induced by heat-stable, filterable substances called “pyrogens” and then he chose the rabbit as the animal model. But Rabbits test may cause false positives. Moreover, it needs to inject three rabbits per test.

Limulus Amebocyte Lysate (LAL) testing is including:
• Gel Clot
• Endpoint Chromogenic
• Automated assays
– Turbidimetric
– Chromogenic
Limulus polyphemus—the American Horseshoe Crab was employed. The cardiac membrane is disinfected with a sterile alcohol wipe. A sterile needle is gently inserted and the blood begins to flow. Bleeding takes seconds and the needle is removed as the flow of blood slows. Clotting takes place at the point of needle insertion.
Host Defense Mechanism:
. Granules contain clotting factor / enzymes.
. The crab can survive having most of its blood clot.
. Gram-negative bacteria or endotoxin causes blood cells (amebocytes) to release proteins into the plasma (hemolymph) causing the blood to coagulate.
. Coagulation kills bacteria and neutralizes endotoxin.

LAL Chromogenic Test

LAL Turbidimetric Test

Manufacture of LAL
. Collect animals
. Extract blood
. Centrifuge blood
. Wash cell
. Lyse cell
. Extract proteins

1977 FDA approved LAL test for release of medical devices
Most devices are very straightforward
- Water rinses
- No interference
- Endotoxin recovered form challenge
Treatments to Overcome Inhibition/Enhancement
• Dilution
• pH Adjustment
• Heating
• Surfactant/Dispersing Agent
• Cellulase or Glucan Blockers
• Divalent Cation addition
• Ultrafiltration


Biological Waste Management

The public lecture entitled “Biological Waste Management – Anaerobic Digestion, Composting and Vermicomposting” presented by Professor Eliot Epstein on 11 March 2008 at 6:30am in Hong Kong Baptist University.

He introduces 3 types of biodegradable methodology for waste management and analysis the advantage and disadvantage in each method.

Anaerobic digestion is a process in which microorganisms break down biodegradable material in the absence of oxygen. The process is widely used to treat wastewater sludges and organic wastes because it provides volume and mass reduction of the input material.

Composting is the aerobic decomposition of biodegradable organic matter, producing compost. The decomposition is performed primarily by facultative and obligate aerobic bacteria, yeasts and fungi, helped in the cooler initial and ending phases by a number of larger organisms, such as ils, and other families representing ants, nematodes and oligochaete worms.
Vermicompost (also called worm compost, vermicast, worm castings, worm humus or worm manure) is the end-product of the breakdown of organic matter by some species of earthworm. Vermicompost is a nutrient-rich, natural fertilizer and soil conditioner. The process of producing vermicompost is called vermicomposting .

He does not believe that any one technology should be used by HK to solve the solid waste problem. But he believe the potential solutions are:
i) initiating an aggressive recycling program;
ii) using composting to recycle food waste from markets;
iii) considering anaerobic digestion and waste to energy before considering incineration;
iv) No consider and waste money on vermiculture.


Three Quality Gurus have long life

Recently, Juran has passed away at 103 years old. He is the longest life among quality gurus.
Eventhough it is no scientific evidence about life and studying of quality, the following 3 quality professionals are comparative long live.

Dr. W. Edwards Deming is known as the father of the Japanese post-war industrial revival and was regarded by many as the leading quality guru in the United States. He passed away on December 20, 1993 at the age of 93.

Philip B. Crosby, who championed the zero-defects concept and preached that “quality is free,” has 75, passed away on August 18, 2001.

Dr. Joseph M. Juran, noted author and "father" of modern day Quality Management, passed away on February 28, 2008, from natural causes. He was 103 years old, and was physically and mentally active until his death


Learn Team Building through Samba

This paper discusses the team building through Samba dancing for departmental talent show in annual dinner. When we received the mission to perform a dancing show which represented our department, we have a very clear team goal and target.

Goal and Target:
It remains three week for us to practice the Samba. In the beginning, the practice schedule is planned to be practice two day per week in lunch hour. We have planned 4 pair for Samba and Drum player sole. Time is tight and participants are not enough.

Individual Resource:
One of our colleagues is familiar with Samba and she works as our dancing teacher. Another colleague who is familiar with music and drum player; and he prepares the background music. After that we need to recruit 7 colleagues as dancers. Initially, there are only 2 girls and 2 boys to join the practice but it is only half participants in our target. Under no circumstance, some colleagues are encouraged and forced to join.

Encourage Team Members to Develop Skills:
The first lesson, we have learned the basic step of Samba. At that time, every participant have practice the same posture and motion. We listen to the beat and rhythm. However, some people come late, no show or can’t achieve the progress. During the dancing pair matching, our teacher selected at least one of partner with good sense of rhythm that can help the whole performance. Our dancing teacher works as team leader to motivate every one when we achieve a certain level. Some team member joined us late (e.g. after 3 lesson). Team leader is coaching them individually and assigns one of the best team members to lead the others to practice. When there is only a week before annual dinner, all dancing team members request to practice more times spontaneously. The commitment is more obviously.

Communication and Involvement:
We have a communication platform to update all department members about our practice progress and encourage others to join us. We show the whole arrangement of dancing show to all staff in the department. The sequence of the show is 1) Samba by 4 dancing pairs; 2) Sole of Drum player & dancer and 3) all people to join the dance of “Macarena”. Two days before annual dinner, we have up to 30 colleagues to join the “Macarena” practice. It is very high team spirit at the time. Finally, we have a good show in annual dinner and all audience is appreciated.

Team building is not only one super dancer in the show but it needs every team member involvement and whose understand the Samba steps, rhythm, concentration, matching and respect with partner. In here, drumming is a great way to break down barriers, create common environment and teach people the value of listening and learning together as a team. Leader needs encouraging individuals to work with others towards a common goal. During this Samba dancing, we learn the following key points about effectiveness of team:
1) Clear objectives: Talent Show in annual dinner
2) All team members have opportunities to contribute to objective setting
3) Support for each other during practice
4) Regular review of team performance for learning rather than blaming
5) Good communication
6) Sufficient time for planning
7) There is a broad mix of skills (dancing & drumming) and personal attributes.
After the show, every team members are satisfied their performance and rewarded by learning Samba.


Roberto Saco, ASQ President - Elect, Visiting HK

Mr. Roberto Saco visited Hong Kong and he had exchanged ideas with the leadership of HKSQ at 8:00 AM for a breakfast meeting in Peninsula Hotel on 26th Feb 2008.

HKSQ participants: Dr. Albert Tsang, Dr. K.S. Chin, Dr. Aaron Tong and Ir. Lotto Lai.

We learned a lot about Roberto's views on ASQ's future directions and the current quality management practices in the US. ASQ's outreach programs and development of collaborative relationships with overseas organizations would enhance the ASQ brand and the Society's contribution to enabling achievement of performance excellence in organizations around the world.


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