M.P. Szczepanik

The examination of biophysical parameters of skin (transepidermal water loss, skin hydration and pH value) in different body regions of normal cats of both sexes

The purpose of this study was to evaluate transepidermal water loss (TEWL), skin hydration and skin pH in normal cats. Twenty shorthaired European cats of both sexes were examined in the study. Measurements were taken from five different sites: the lumbar region, the axillary fossa, the inguinal region, the ventral abdominal region and the left thoracic region. In each of the regions, TEWL, skin hydration and skin pH were measured. The highest TEWL value was observed in the axillary fossa (18.22 g/h/m2) and the lowest in the lumbar region (10.53 g/h/m2). The highest skin hydration was found in the inguinal region (18.29 CU) and the lowest in the lumbar region (4.62 CU). The highest skin pH was observed in the inguinal region (6.64) and the lowest in the lumbar region (6.39). Statistically significant differences in TEWL were observed between the lumbar region and the left side of the thorax region (P=0.016), the axillary fossa (P=0.0004), the ventral region (P=0.005), and the inguinal region (P=0.009). There were significant differences in skin hydration between the lumbar region and the left thorax (P=0.000003), the axillary fossa (P=0.002), the ventral abdomen (P=0.03), and the inguinal region (P=0.0003) as well as between the thorax and the ventral abdomen (P=0.005). TEWL was higher in females (15 g/h/m2) than in males (4.57 g/h/m2). Skin hydration was higher in females (13.89 CU) than in males (12.28 CU). Significant differences were not found between males and females for TEWL and skin hydration. Skin pH was higher in males (6.94) than in females (6.54), which was significant (P=0.004).

Biophysical parameters of rats’ skin after the administration of methimazole

Abstract The paper describes the influence of oral administration of methimazole on biophysical skin parameters. Wistar rats of different sex (220-260 g) were used in the experiment. Biophysical skin parameters, such as transepidermal water loss (TEWL), corneometry, and pH were examined at seven-day intervals. Significant changes in the parameters were observed on the 7th d of methimazole administration. The changes were observed in both sex but males appeared to be less sensitive in that respect. Changes in the parameters in the females showed rapid mechanisms, which normalised transepidermal water loss and skin hydration, as well as restored skin barrier functions. TEWL, skin hydration, and skin pH measurements allow an early assessment of skin barrier dysfunction after administration of this drug.

Evaluation of the correlation between Scoring Feline Allergic Dermatitis and Feline Extent and Severity Index and skin hydration in atopic cats

BACKGROUND Evaluation of the severity of clinical signs of cats with allergic skin diseases has used two scoring systems: Scoring Feline Allergic Dermatitis (SCORFAD) and the Feline Extent and Severity Index (FeDESI). The integrity of the cutaneous barrier can also be evaluated by measuring skin hydration. A correlation between the clinical score and skin hydration has been observed in humans and dogs with atopic dermatitis (AD). HYPOTHESIS To demonstrate a correlation between the clinical score and skin hydration of cats affected with presumed AD. ANIMALS European short hair cats (n = 18): 11 females and seven males with a confirmed diagnosis of AD. METHODS SCORFAD and FeDESI scores were calculated and the measurements of skin hydration were assessed from seven body sites using corneometry. The correlation between the SCORFAD and FeDESI systems and skin hydration of each site, and the average skin hydration was calculated. RESULTS There was a positive correlation between the SCORFAD score and skin hydration for the axilla, thorax and forelimb; for FeDESI and axilla and lumbar sites. There was a negative correlation between the FeDESI and skin hydration for the pinna (r = -0.47). CONCLUSIONS AND CLINICAL IMPORTANCE Measurements of skin hydration could be a useful tool for the evaluation of allergic cats. There is limited evidence of any useful correlation between clinical scoring systems and measurements of hydration. The pinna may be a suitable region for the assessment of skin barrier function in normal and allergic cats.

Content of selected amino acids in the gastrocnemius muscle during experimental hypothyroidism in rats

Abstract Introduction: Thyroid hormones affect protein turnover, and in the case of hypothyroidism a decrease in protein synthesis and reduced release of certain amino acids from skeletal muscles are observed. Changes in the amino acid system of skeletal muscles may be responsible for the occurrence of muscle disorders. Material and Methods: The study measured the content of selected amino acids in the gastrocnemius muscle of Wistar rats during experimental hypothyroidism induced by oral administration of methimazole at a concentration of 0.05% in drinking water for 90 d. The rats were divided into four groups: E1 (n = 6) - experimental males, E2 (n = 6) - experimental females, C1 (n = 6) - control males, and C2 (n = 6) control females. Results: A statistically significant reduction occurred in leucine, isoleucine, and 1-methylhistidine levels in males, and 1-methylhistidine in females, in comparison to the control groups. Conclusion: The hypothyroidism-induced changes in amino acid content may be responsible for the occurrence of skeletal muscle function disorders.

Preliminary study of guard hair morphology in four dog breeds

BACKGROUND Morphological differences between mammalian hair types are useful for species distinction. Differences in animal hair structure are observed between species, whereas there may be breed differences within a species. HYPOTHESIS Guard hair structure may vary between different dog breeds. ANIMALS Hair samples were collected from 73 dogs of four breed types (wire-haired Dachshund, Labrador retriever, German shepherd dog and Yorkshire terrier). METHODS Hair was measured and analysed by scanning electron microscopy. The following were evaluated: hair thickness; medulla to hair cross-sectional area ratio; scale density, pattern and margins; and medulla shape, composition and structure. RESULTS There were significant differences in all measured parameters between breeds. CONCLUSIONS AND CLINICAL IMPORTANCE These study findings may be useful for the study of classifying dog breeds and for forensic identification of a dog breed through hair sampling.

Relationship between Total Homocysteine, Folic Acid, and Thyroid Hormones in Hypothyroid Dogs

Background Both elevated homocysteine and decreased folic acid concentrations are observed in human patients with hypothyroidism and can influence the development of numerous secondary disorders. Objectives The aim of the study was to assess total homocysteine concentration in serum and to examine its relationship with the concentration of folic acid and thyroid hormones (tT4 and fT4). Animals Ten healthy and 19 hypothyroid client‐owned dogs. Methods Dogs with clinical signs of hypothyroidism had the diagnosis confirmed by additional tests. Total homocysteine, folic acid, total thyroxine, and free thyroxine concentrations in serum were evaluated. Results Hypothyroid dogs were diagnosed with increased homocysteine (median 22.20 μmol/L; range, 16.50–37.75) and decreased folic acid (median 20.62 nmol/L; range, 10.54–26.35) concentrations, as compared to healthy dogs (11.52 μmol/L; range, 10.00–16.65 and 30.68 nmol/L; range, 22.84–38.52, respectively). In sick dogs, total homocysteine was inversely correlated with folic acid (ρ = −0.47, P < 0.001), total thyroxine (ρ = −0.69, P = 0.0092), and free thyroxine (ρ = −0.56, P = 0.0302). Conclusions Hypothyroidism in dogs causes hyperhomocysteinemia. Concomitant mild folic acid decrease in hypothyroid dogs might be as a result of hyperhomocysteinemia.

The influence of non-specific anti-pruritus treatment with cyclosporine A on transepidermal water loss (TEWL) in natural atopic dermatitis in dogs.

Atopic dermatitis is a common allergic skin disease in dogs. Monitoring the progress of treatment and the assessment of the severity of disease symptoms are crucial elements of the treatment procedure. One of the common means of assessing the severity of the clinical signs of the disease is the CADESI 03. Research studies have pointed to a possibility of assessing the severity of skin lesions by means of measuring biophysical skin parameters such as TEWL, skin hydration and erythema intensity. The aim of the study was the assessment of changes in TEWL and CADESI values measured in ten different body regions during non-specific anti-pruritus treatment. The examination was performed on ten dogs with atopic dermatitis (age from 2.5 years to 7 years, mean age 3.8 years). The measurements were performed in the following body regions: the lumbar region, the right axillary fossa, the right inguinal region, the ventral abdominal region, the right lateral thorax region, the internal surface of the auricle, interdigital region of the right forelimb, cheek, bridge of nose and the lateral site of antebrachum. A statistically significant decrease in CADESI values was reported starting from the second week of treatment. In the case of the mean TEWL values, a fall was observed after one week of treatment in the ventral abdominal region and the interdigital region, after two weeks of treatment in the axillary fossa and the inguinal region, and after three weeks in the cheek and the lateral thorax region. There was no statistically significant decrease in TEWL values in the course of treatment in four other regions.