Dental Did You Know: Baseball Players and Chewing/Smokeless Tobacco

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Although the latest information was from the 1988-1990 spring training seasons, the data showed that 40% of players used smokeless tobacco. 50% of those had leukoplakia-like lesions where they held it in their mouths while 2% of  non-users had similar lesions.

Source: Feferman I, Healthline: Running Risks, Oral Health, May 2012, Vol 89, No 4, pg 26.


Hans Skariah, B.Sc., DMD
Promenade Court Dental Health Group in Mississauga
2233 Hurontario St., Mississauga, ON, Canada
(1/2 km north of the QEW in the Dome Building)
(905) 273-7100

Eliminating ringworm spores from the home

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Winn grant W12-034
Decontamination of household textiles exposed to Microsporum canis spores
Investigator: Karen A. Moriello; University of Wisconsin-Madison

Ringworm is a superficial fungal skin disease that affects all animals, including cats. In cats, the most commonly isolated pathogen is Microsporum canis. This disease is important because it is highly contagious to cats and transmitted to people making it a public health concern. Ringworm can infect any cat, but the most commonly infected are the most adoptable (kittens and juveniles), old cats with other illnesses, and cats in animal shelters or rescue organizations. This skin disease is curable but treatment can be challenging because diseased cats shed large amounts of infective material (spores and infected hairs) into the environment. Effective cleaning is necessary to prevent spore contamination of the environment and prevent cats from becoming re-infected or “dust mop carriers”. Information on effective cleaning of hard surfaces (walls, counters, etc.) is available, but no evidence-based information is available for household textiles-fabric, clothing, carpeting, etc.

Microscopic view of M. canis

The purpose of this study is to determine the efficacy of decontamination options for household textiles (e.g., towels, fabric, and carpet) with a goal of identifying safe and effective practices. Common household textiles will be experimentally contaminated with naturally infective material and the following cleaning techniques tested: washing in cold or hot water with or without bleach pre-soaking, vacuuming rugs at different lengths of time, rental carpet cleaners, and high pressure/high temperature commercial cleaning of carpets. This study will determine which of these techniques are excellent, adequate, marginal or unsatisfactory for decontamination. Information will be immediately useful for people treating cats with ringworm.

This project is available for sponsorship. When you sponsor a project, your name will be added to the list of the project's supporters on our website and in any publications we produce about the project. You will receive exclusive pre-publication reports on the progress of your chosen project as they become available, and a final report at its conclusion.

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Feline Health Symposium: Diving into the Gene Pool

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Registration is now open for the 34th Annual Winn Feline Foundation Feline Health Symposium. This year's event, "Diving into the Gene Pool", will take place on Thursday, June 28, 2012, from 4:00 to 6:00 pm at the Boston Marriott Quincy, in Quincy, MA.

“We are excited to announce that two preeminent feline healthcare researchers will be delivering the program. Leslie Lyons, PhD, University of California, Davis will present ‘The Next Generation of Feline Genetics’ and John Rush, DVM, DACVIM, DACVECC, Tufts University will speak on ‘Feline Cardiomyopathy - More than Genes! New thoughts on Causes, Diagnosis, and Treatment’",stated Dr. Vicki Thayer, Winn Feline Foundation Board President.

Dr. Lyons will speak on recent genetic sequencing of the cat which has led to development of a powerful new genetic resource, the cat 63K DNA array. Dr. Lyons will present examples of recent successes for identification of mutations causing cat traits and diseases. In addition, discussion will cover a new study design to evaluate more challenging traits, such as FIP resistance and susceptibility, and other complex conditions in the cat. While genetic mutations contribute to many forms of hypertrophic cardiomyopathy (HCM) in the cat, these mutations cannot explain all of the manifestations of the disease. Dr. Rush will present information and research relative to diagnostic testing, dietary implications, and new drugs for treatment of feline cardiomyopathy.

All event proceeds will benefit worldwide medical research on feline HCM via Winn’s Ricky Fund, established in 2002 with the specific purpose of raising funds for feline HCM research. 

The registration fee, which includes light snacks with a cash bar, is $25. Reservations are required by June 17, 2012. Detailed information and registration options are available on our website and in the event flyer.

For more information, contact:
Maureen Walsh, Winn Chief Executive Officer
mwalsh@winnfelinehealth.org

Improving treatment of feline kidney disease

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Winn grant W12-039
Administration of pimobendan to cats with chronic kidney disease
Investigators: Mary Anna Labato, Brandi R. Gallagher, John Rush; Tufts University

Chronic kidney disease (CKD) is one of the most common reasons geriatric cats present to the veterinarian. CKD is considered irreversible and progressive, and effective treatments are limited. A common co-existing condition seen in feline CKD patients is heart disease. Two of the investigators in this study have administered pimobendan to cats with combined kidney and heart disease. The patients had developed congestive heart failure (CHF) secondary to intravenous fluid administration, a typical standard of care for kidney disease. In some of these patients, addition of pimobendan resulted in a great improvement in kidney values and clinical response. Tolerability and safety of this drug has already been established in cats with heart disease. This will be a pilot study to assess the tolerability of pimobendan in cats with CKD and search for benefits in comparison to the current standard of care. Investigating these observations in a larger study will help establish whether pimobendan could be a novel treatment for cats with CKD. 

This project is available for sponsorship. When you sponsor a project, your name will be added to the list of the project's supporters on our website and in any publications we produce about the project. You will receive exclusive pre-publication reports on the progress of your chosen project as they become available, and a final report at its conclusion.

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Parvovirus in cats and dogs

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Stucker KM, Pagan I, Cifuente JO, et al. The role of evolutionary intermediates in the host adaptation of canine parvovirus. J Virol 2012;86:1514-1521.

Canine parvovirus (CPV-2) emerged in the late 1970’s as a variant of feline panleukopenia virus (FPV). By the early 1980’s, this variant was replaced by new variants that infected both dogs and cats (CPV-2a and -2b). Interestingly, it is now believed that raccoons may have played a role in the evolution of FPV and its adaptation to dogs, and re-adaptation to cats. Through analysis of all of these viruses and variants, the researchers were able to describe the complex sequence of events, involving small changes in the virus were necessary for these changes in host adaptations. Furthermore, they found that these changes had to occur in concert with one another in order for the adaptation to be successful. These findings show how complex this adaptation to new hosts is, and thus why it is not a common occurrence among viruses. [MK]

Related articles: Horiuchi M, Yamaguchi Y, Gojobori T, et al. Differences in the evolutionary pattern of feline panleukopenia virus and canine parvovirus. Virology 1998;249:440-452.

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Feline oral cancer: new treatment options

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Winn grant W11-027
Cetuximab Targeting of Epidermal Growth Factor Receptor in Feline Oral Squamous Cell Carcinoma
Investigators: Stuart Helfand and Krystal Claybrook; Oregon State University

Elderly cats are most at risk for oral cancer

Feline oral squamous cell carcinoma (FOSCC) is a common and deadly cancer for which there are no truly effective therapies. This study’s long-term aim is to suppress growth of FOSCC by interrupting signaling through the epidermal growth factor receptor (EGFR). EGFR-signaling is a known trigger for cell growth making it a desirable target for therapy. The study considers two strategies of interest that share the same goal of impeding EGFR signaling. One method is to use cetuximab for monoclonal antibody blockade of the receptor. The alternate method is use of tyrosine kinase inhibitor (TKI) blockade of the receptor’s activation site. The impairment of signaling suppresses a number of processes that would otherwise promote malignant behavior. 

Previous study results showed EGFR is expressed by the only cell line of FOSCC available and that cetuximab can bind to FOSCC biopsy tissue. Despite the prior data, this investigator unexpectedly discovered that cetuximab did not bind to the cells. The study then turned to pursuing the alternate approach to block EGFR signaling by examining a TKI drug, gefitinib, on proliferation of this cell line. Results in this instance confirmed the ability to interrupt EGFR signaling in the cell line by using gefitinib, resulting in suppression of the tumor cells. Data has indicated that this approach is effective and may facilitate use of lower drug doses while achieving superior cell killing.

Additional time is needed to confirm the results and validate targeting of gefitinib (and another TKI drug, dasatinib) to EGFR by western blot analysis. [VT]

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Feline stem cells

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Webb TL, Quimby JM, Dow SW. In vitro comparison of feline bone marrow-derived and adipose tissue-derived mesenchymal stem cells. J Feline Med Surg 2012;14:165-168.

Bone marrow derived stem cells

The use of mesenchymal stem cells (MSC) is being evaluated as a treatment option for a number of different diseases. MSC can be derived from a variety of adult tissues, are fairly non-immunogenic, and their immunosuppressive properties may be of benefit in many immune and inflammatory disease processes. In cats, MSC are being proposed for use in chronic inflammatory or degenerative diseases, such as inflammatory bowel disease and osteoarthritis.

MSC are primarily collected from bone marrow (BM) or adipose tissue (AT) and are then enriched and enhanced before transfer into patients. This study looked at the growth properties and phenotype of feline BM-MSC and AT-MSC from four healthy, young donor cats. The results showed that mesenchymal stem cells isolated from AT proliferated significantly faster than BM-MSC. Also, it was noted that BM-MSC and AT-MSC were similar phenotypically. Therefore, MSC derived from adipose tissue may be the preferred choice for clinical applications when the need for rapid and efficient generation of MSC is important. [VT]
This project was partially supported by a grant from Winn.

Related articles: Quimby JM, Webb TL, Gibbons DS, et al. Evaluation of intrarenal mesenchymal stem cell injection for treatment of chronic kidney disease in cats: a pilot study. J Feline Med Surg 2011;13:418-426.

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Welcome to the first blogger post for SkinPathOnline

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Welcome to the first blogger post for SkinPathOnline

Hello everybody,
Welcome to the inaugural SkinPathOnline blogger post. The blog will keep you up to date with the latest in all aspects of skin pathology (dermatopathology) including laboratory techniques and interesting articles that might be worthy of a read.
I will be posting weekly (time permitting) so everything should be fairly current. Please don’t hesitate to send any questions, queries, comments, whatever you feel like, to my email address (feedback@skinpathonline.com).
Also my website (www.skinpathonline.com) will be up and running in the near months. It will be a great site for anyone involved in histology from laboratory technicians, medical scientists, to pathologists. It will be a place to -  learn diagnostic tips, discuss techniques (eg. what worked and what did) and absolutely anything else. So keep an eye out and I will let you all know when it goes live.
PS – don’t forget to follow me on twitter (@skinpathology)

Sentinel Lymph Node Biopsy. Is it useful?

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 I have recently read an article that caught my eye and somewhat relates to skin pathology. The article was entitled  ‘Axillary Dissection vs No Axillary Dissection in Women With Invasive Breast Cancer and Sentinel Node Metastasis’ and was in the February 9th, 2011 issue of the Journal of the American Medical Association. Although this relates to patients with breast cancer I wonder if there will be any overflow of this argument into the ongoing debate over the use of sentinel lymph node biopsy (SLNB) with regards to patients with melanoma.

The results of the aforementioned study showed “among patients with limited sentinel lymph node (SLN) metastatic breast cancer treated with breast conservation and systemic therapy, the use of SLND (sentinel lymph node dissection) alone compared with ALND (axillary lymph node dissection) did not result in inferior survival.” This result has also been mirrored in multiple melanoma SLNB studies. Many people have and still continue to argue over the pros (eg. without a SLNB it is not possible to accurately stage melanoma according to international guidelines) and cons (eg. the impact of complete lymph node dissection (CLND) on a patient’s immune capability).I wonder if in the future SLNB will remain standard practice or if it was a good idea at the time.Many thanks for reading and hopefully this post will get some interesting comments and I am sure it will.

Also don’t forget to follow me on twitter (@skinpathology)
www.skinpathonline.com (will be up in the near future)

PS. This is the link for the JAMA article (http://jama.ama-assn.org/content/305/6/569.abstract)

Non-melanoma skin cancer (NMSC) treatments

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Below are the most common treatments available, plus a brief description, once a NMSC has been diagnosed (usually a basal cell carcinoma or a squamous cell carcinoma).
Surgical excision (standard) – the most common and preferred form of treatment. Good for nodular tumours with a sharply demarcated border. Has a high cure rate and is dependent on the closeness of tumour to the resection margin in regards to the pathology (ie. the closer the tumour is to the margin the more likely it is to recur). One let down is the bread loafing technique which results in only approximately 5% of the actual margins being visualised by the pathologist for assessment of complete excision.
Moh’s /  Moh’s Micrographic Surgery – form of treatment with the highest reported cure rate (~97-99%). This technique results in the entire peripheral margins and the deep margins being visualised and assessed for completeness of excision (this is why the cure rate is so high). One let down is the time-consuming nature of the technique and the specialised training that is involved.
Topical chemotherapy – the most common available topical chemotherapy agents include 5-fluorouracil (5-FU) and 5% imiquimod. Generally speaking 5-FU works by inhibiting DNA replication therefore the growth of the tumour and imiquimod works by modifying the local tumour immune response of the patient. Advantages include the non-invasiveness topical therapy. Disadvantages are that, used alone, they can only be used on superficial tumours and not invasive tumours. Experimentation of their use in conjunction with other treatments (eg. curettage then topical treatment, or topical use to reduce tumour size before excision) have resulted in reports of higher cure rates.
Curettage +/- Electrodissection – put simply the tumour is physically scrapped away then the treated area is exposed to an electrical current which results in the softening of the skin and the procedure is repeated until the treating physician is satisfied excision is complete. The curettage portion technique can be applied alone without the electrodissection. This technique is usually reserved for site which are cosmetically unimportant (eg back). The cure rate is dependent on how aggressive the technique is applied (ie. the more the aggressive the higher the cure rate) and the growth type of the tumour being treated (ie. the more invasive the tumour the lower the cure rate).
Cryotherapy – one of the older treaments for NMSC which involves treatment of the tumour most commonly with liquid nitrogen. Cure rate can be high but there is reduced tumour margin control resulting in a higher recurrence rate.
Photodynamic Therapy (PDT) – fairly new technique which involves applying a topical photosensitizer to the target tumour and then exposure of the target area to light. This results in the production of aggressive chemicals which damage the cell causing death. Disadvantages include the ineffectiveness on invasive and thicker tumours due to lack of light penetration, and high cost. Advantages include the non-invasiveness of the technique.
Radiotherapy – usually reserved for older patients or where the surgical removal of the tumour is not a viable option. Has a reported cure rate of approximately 80-95%. Tumours recurring after radiotherapy are generally more aggressive and can become radiotherapy resistant.
I welcome any comments or other therapies you have encountered.
Keep and eye out for www.skinpathonline.com.
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My email is feedback@skinpathonline.com for any questions or queries.

Cutaneous Squamous Cell Carcinoma – Overview

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Squamous cell carcinoma (SCC) is defined by the World Health Organisation as ‘a malignant neoplasm of epidermal (and mucous membrane) keratinocytes in which the component cells show variable squamous differentiation.’  Most SCCs appear on the areas of the skin which get the most sun exposure though this is not the only place which the can arise. SCCs can also arise on mucosal areas such as on the lip. Patients who have a pale complexion and those who do not tan readily are at a greater risk. SCC is very uncommon in the Black population.
The most important causative agent is sun exposure, more correctly UVB radiation. Others factors that have been incriminated include human papilloma virus (HPV) infection, ulcers, immunosuppression and radiotherapy. Patients with organ transplants are also at a greater risk. SCC can be fatal in some cases (most commonly found in Australia) giving rise to the notion that sun exposure, which causes DNA damage and also suppresses the skin immune system, plays a lead role in the cause of aggressive SCCs. 
As sun exposure is the major cause factor of SCC, it is no surprise that the forehead, ears, scalp, face, neck, back of the hands and lips are the most common places to find SCCs on the human body.
SCCs commonly appear as plaques/nodules with an elevated/indurated, crusty surface. The areas immediately surrounding the SCC show the typical signs of sun damage.
I have previously blogged about the prognostic factors of SCC, please click on the link to see more (Prognostic Factors of Cutaneous Squamous Cell Carcinoma)
Thanks for reading and I welcome any comments.
Keep an eye out for my website, soon to be up and running (www.skinpathonline.com)
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Periodic-Acid Schiff Diastase (PASD) Special Stain – Method and Tips

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In my previous post I covered the Periodic Acid-Schiff reaction (PAS) special stain which is by far the most common stain performed in a routine histology laboratory. A variation on this technique call the Periodic Acid-Schiff Reaction with diastase digestion (PASD) is another commonly performed special stain which I will be covering in this post.  The variation on the PAS technique involves simply exposing the section to the diastase enzyme amylase prior to continuing with the standard PAS method. The term ‘diastase’ refers to any enzyme that catalyses the breakdown of starch into maltose the dextrose. The diastase enzyme acts by cleaving the a-glucosidic 1-4 linkages of starch or glycogen (aka animal starch) leading to the formation of maltose and dextrose (maltose and dextrose are water-soluble sugars). So when sections are pre-exposed to diastase before commencing the PAS technique the glycogen within the tissue is broken down into maltose and dextrose which are dissolved and washed away when the section is rinsed sufficiently in tap water. 
The diagnostic purpose of performing the PASD technique include 
-         the removal of glycogen to make it easier to identify mucins stained by the PAS technique
-         analysis of glycogen deposits within the liver 
-         highlighting a thickened basement membrane for example in lupus

Solutions
Diastase solution – 1 part human saliva to 9 parts distilled water. 
1% aqueous periodic acid – from PAS method.
Schiffs Reagent – from PAS method.

Method
1. Take sections to water.
2. Expose sections to diastase solution for 30 minutes at room temperature.
3. Wash sections thoroughly in tap water.
3. Continue with PAS method from step 2.

Tips - Always run a PAS and a PASD control with every batch of PASD stains to ensure your diastase solution is working. This author has found a glycogen rich liver control to be most sufficient. This author also runs a PAS and PASD for all PASD requests.
- Commercial amylase is available instead of using a saliva solution. Commerical amylase sometimes requires different incubation temperatures and conditions so check this before using. This author has found that a saliva solution is easiest due to its ease of preparation, availability and plus it is free.
- Put all sections onto to ‘sticky’ slides ie. Superfrost plus slides or their equivalent as the saliva solution causing some lifting of the section from the slide. This is reportedly more prevalent in sections exposed to the commercial amylase solution.
Thanks for reading and I welcome any comments.
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Persistent Melanocytic Nevi: A Review and Analysis of 205 cases

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Great article in the June 2011 issue of the ‘Journal of Cutaneous Pathology’ regarding persistent melanocytic naevi. 
Good reading for those interested in the subject.  Things of note are
- female predominance (reason unclear)
- back is the most common site followed by abdomen then chest
- mean time between original biopsy then biopsy of persistent naevus was 9.7 months
- dysplastic naevi were most likely to recur
- persistent melanocytic naevi were more likely to be initially removed via shave biopsy
Link to the article below
http://onlinelibrary.wiley.com/doi/10.1111/j.1600-0560.2011.01692.x/abstract
Thanks for reading and I welcome any comments
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Verhoeff Van Gieson Elastin Special Stain – Method and Tips

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Elastin is a connective tissue protein which allows the tissues of the body to return to their original shape after distortion or stretching. Elastin fibres can be of varying size and diameter and are particularly well seen histologically in sites such as the lung, heart, blood vessels and the dermis.  Histological demonstration of elastin fibres (or lack of them) are important in diagnostic pathology for conditions such as arteriosclerosis, temporal arteritis and elastosis. Fine elastic fibres are not so easily seen on standard haemtoxylin and eosin (H+E) staining therefore special stains which demonstrate elastin clearly are vital.
There are many elastin special stain techniques such as Weigert-Type, Orcein, Aldehyde-Fuchsin and Verhoeff’s. The most common is Verhoeff’s technique of staining elastin due to its quick method and strong elastin colour result. Below is the author’s favoured method for demonstrating elastin which is a version of the Verhoeff’s.
SOLUTIONS
Verhoeff’s solution – (5ml 5% alcoholic haematoxylin) + (2ml 10% aqueous ferric cholride) + (2ml Lugol’s iodine) MAKE IMMEDIATELY PRIOR TO USE.
Note – Lugol’s iodine = 2g potassium iodine dissolved in ~4ml of distilled water, then dissolve 1g iodine, then make up to 100ml.
2 % aqueous ferric chloride
Van Gieson counterstain = (100ml saturated aqueous picric acid) + (1% aqueous acid fuchsin), boil for 3 mins then filter.

METHOD
1. Take sections to water.
2. Stain with Verhoeff’s solution for 15-20 mins.
3. Wash well in tap water.
4. Differentiate in 2% aqueous ferric chloride until only elastin fibres remain darkly stained.
5. Wash in tap water for 5 mins.
6. Counterstain with Van Gieson for 3 mins.
7. Dehydrate, clear and mount.
TIPS
- aim for slight under-differentiation as the Van Gieson stain will continue the differentiation though more slowly.
- dehydrate quickly as alcohol can leach some of the Van Gieson stain from the section. You can accelerate dehydration by blotting the section with filter paper.
Thanks for reading and I welcome any comments.
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Lack of UV-A Protection In Daily Moisturising Creams

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Came across another interesting article in the May edition of ‘The Archives of Dermatology’ 2011. The article is entitled ‘Lack of UV-A Protection In Daily Moisturising Creams’ on page 618.   Ultraviolet radiation (UV) contains UVA, UVB and UVC subtypes. The major source of UV exposure for humans is sunlight. The earths ozone layer blocks approximately 98% of all UV radiation and the 2% which reaches the earths surface 99% is of the UVA subtype. UVB can cause direct DNA damage whereas UVA causes indirect damage of DNA via the formation of free radicals. Therefore it is important any sunscreen solution contains both UVA and UVB filters. 
This article reported the estimated long-range UVA1 protection of 29 creams.
Major points of note from the article include
- Most daily facial creams contain ingredients known as UV filters claiming broad spectrum UV protection.
- Sun protection factor (SPF) doesn’t reflect UV-A1 protection.
- UVA penetrates window glass whereas UVB is blocked, therefore women working indoors need to protect themselves from UVA exposure.
- Of the 29 creams 6 didn’t contain any UVA1 filters.
I recommend reading the full article as it is an interesting read. Below is a link to the article.
Lack of UV-A Protection in Daily Moisturizing Creams
Steven Q. Wang; Jacqueline M. Goulart; Henry W. Lim
Arch Dermatol. 2011;147(5):618-620  Thanks for reading and I welcome any comments.
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Modified Ziehl–Neelsen Stain For Leprosy Bacilli – Method and Tips

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Leprosy bacilli in comparison with tubercle bacilli are much less acid- and alcohol-fast. The leprosy bacilli’s lipid envelope is also much more affected by the fat solvents traditionally used to dewax sections (i.e. Xylene). Due to these factors a modification on the standard Ziehl-Neelsen technique is used for the demonstration of leprosy bacilli.   Below is the author’s preferred technique. 
SOLUTIONS  

Dewaxing solution – equal parts of liquid paraffin and rectified turpentine 
Carbol Fuchsin – as per standard Ziehl-Neelsen technique  Methylene blue counterstain – as per standard Ziehl-Neelsen technique  10% sulphuric acid 
METHOD 
1. Dewax in ‘dewaxing solution’ described above for 30 minutes. 
2. Blot dry and wash in running water for approximately 10 minutes. 
3. Stain with filtered Carbol Fuchsin for 30 minutes at room temperature. 
4. Wash well in tap water. 
5. Differentiate in 10% sulphuric acid until section is pale pink. 
6. Wash well in tap water.
7. Counterstain with Methylene Blue for 15 seconds. 
8. Wash well in tap water. 
9. Blot dry, clear and mount. 
TIPS 
- This author always puts sections on ‘sticky’ slides to prevent any floating off. 
- There are many variations on the ‘softer dewaxing solution’ for the modified Ziehl-Neelsen technique for leprosy bacilli including: - Two parts xylene to one part vegetable oil / clove oil / groundnut oil / olive oil / cottonseed oil. 
- Residual oil on the section after washing prevents shrinkage of the section. 
- Place slides directly from heater into dewaxing solution as this helps quicken the dewaxing.
- Some methods use a weaker acid-alcohol solution for differentiation, but this author prefers 10% sulphuric acid as it is quicker. 
- Don’t be alarmed when the section is placed into the sulphuric acid as it will turn a black colour. It will return to a pink colour when placed back in water.
- Ensure the counterstain colour isn’t too intense as this can mask some leprosy bacilli and even turn them a purple colour. 
- This is author lets the sections dry after washing after counterstaining and then directly mounts them.
I welcome any other tips and comments.
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