Maria Karayannopoulou

The Lymph Drainage of the Neoplastic Mammary Glands in the Bitch: A Lymphographic Study

The purpose of this investigation was to study the lymph drainage of the neoplastic mammary glands in the bitch using indirect lymphography. The main conclusions drawn from the study of 41 natural cases were as follows: the first or cranial thoracic and second or caudal thoracic neoplastic mammary glands usually drain into the ipsilateral axillary lymph nodes and rarely into the ipsilateral axillary and sternal lymph nodes, simultaneously. The third or cranial abdominal neoplastic mammary gland usually drains into the ipsilateral axillary and superficial inguinal lymph nodes simultaneously, but sometimes only cranially into the ipsilateral axillary lymph nodes. Rarely, it drains only caudally into the ipsilateral superficial inguinal and medial iliac lymph nodes, simultaneously. The fourth or caudal abdominal neoplastic mammary gland usually drains only caudally into the ipsilateral superficial inguinal lymph nodes. Rarely, it drains into the ipsilateral axillary and superficial inguinal lymph nodes simultaneously. The fifth or inguinal neoplastic mammary gland usually drains into the ipsilateral superficial inguinal lymph nodes but rarely, does it also drain into the ipsilateral popliteal lymph node and into a lymphatic plexus at the medial aspect of the ipsilateral thigh. Lymphatic connections between the neoplastic and adjacent normal mammary glands were demonstrated in only one case. The lymph drainage pattern of the neoplastic mammary glands is slightly different to that described in normal glands using the same radiographic method.

The Lymph Drainage Pattern of the Mammary Glands in the Cat: A Lymphographic and Computerized Tomography Lymphographic Study

Seventy‐three clinically normal, lactating cats were used to investigate the lymph drainage of 73 mammary glands. In 50 cats of the first group, the number of lymphatic vessels emerging from the examined mammary gland, their course and the lymph nodes into which they are drained were studied by indirect lymphography (IL) after intramammary injection of an oily contrast medium. In 23 cats of the second group, the lymph drainage of the mammary glands was studied by computerized tomography indirect lymphography (CT‐IL) after intramammary injection of a water soluble contrast medium. The following day, the lymph drainage of the mammary gland examined by CT‐IL was studied by IL, as it was described in the first group, for comparison purposes. The main conclusions drawn after this study were as follows: lymph drains from the first and second mammary glands with one or rarely two or three lymphatic vessels to the accessory axillary lymph nodes. Lymph drains from the third mammary gland with one or two and rarely three lymphatic vessels usually to the accessory inguinal lymph nodes or to the accessory axillary lymph nodes. In some cases, it drains to both lymph nodes simultaneously or it may rarely drain only to the medial iliac lymph nodes. The fourth mammary gland with one or two and rarely three lymphatic vessels usually drains to the accessory inguinal lymph nodes. It may rarely drain only to the medial iliac lymph nodes. Mammary lymphatic vessels that cross the midline and lymphatic connection between the mammary glands were not demonstrated. No differences in the mammary lymph drainage pattern between IL and CT‐IL were found.

Effect of locally injected autologous platelet-rich plasma on second intention wound healing of acute full-thickness skin defects in dogs

OBJECTIVES Second intention wound healing may be impaired by wound and host factors and thus more advanced therapies are required for a fast and satisfactory outcome. Platelet-rich plasma (PRP), rich in growth factors and cytokines essential for tissue repair, could improve wound healing. The purpose of this experimental study was to evaluate the effect of locally injected autologous PRP on second intention healing of acute full-thickness skin defects in dogs. METHODS Three 2 x 2 cm full-thickness skin defects were created bilaterally on the dorsolateral area of the trunk of six Beagle dogs. The wounds of one randomly selected side received PRP treatment, whereas the contralateral wounds were left untreated (controls). Wound healing was evaluated by planimetry, laser-Doppler flowmetry measurements of tissue perfusion, and histologically. RESULTS The rate of wound healing did not differ significantly between the two groups. Tissue perfusion was significantly higher in the PRP-treated group (p = 0.008) compared to controls on day 10. Histological evaluation revealed a trend towards greater collagen production and a significantly better collagen orientation (p = 0.019) in PRP-treated wounds on day 20. CLINICAL SIGNIFICANCE Locally injected autologous PRP does not accelerate the healing process, but increases tissue perfusion and may promote the formation of organized collagen bundles in acute full-thickness skin defects in dogs.

ASSESSMENT OF SENTINEL LYMPH NODE METASTASIS IN CANINE MAMMARY GLAND TUMORS USING COMPUTED TOMOGRAPHIC INDIRECT LYMPHOGRAPHY

In the staging process of the breast cancer, demonstrating metastasis of the sentinel lymph node (SLN) has an important prognostic value, in both humans and animals. The aim of this prospective case-control study was to determine the diagnostic value of computed tomographic indirect lymphography (CT-LG) for detecting SLN metastasis in dogs with mammary cancer. Thirty-three female dogs with tumors in the abdominal and inguinal mammary glands were prospectively selected and subjected to CT-LG, 1 and 5 min after injection of 1 ml of contrast agent (iopamidol) in the subareolar tissue of the neoplastic and the contralateral normal mammary glands. The pattern of postcontrast opacification, degree of postcontrast enhancement, and size and shape were assessed in 65 SLNs in total and were correlated with histopathological findings. The absence of opacification or heterogeneous opacification 1 min after contrast medium injection showed the highest sensitivity, specificity, and accuracy (93%, 100%, and 98.4%, respectively). In images taken 1 min after injection, an absolute density value lower than 444 Hounsfield units (HU) in the center of the SLN also provided significant sensitivity and specificity (93.8% and 75%, respectively). The size and shape of the SLN (maximum and minimum diameter, maximum/minimum diameter ratio, maximum diameter/height of fifth thoracic vertebral body ratio) showed the lowest sensitivity and specificity. Results of this study support the hypothesis that CT-LG could help in the assessment of SLN metastasis in cases of mammary gland tumors in dogs.

Evaluation of intra-articular injection of autologous platelet lysate (PL) in horses with osteoarthritis of the distal interphalangeal joint

ABSTRACT Background: Regenerative medicine has become one of the most promising therapies of equine osteoarthritis. Platelet lysate (PL) is rich in bioactive proteins and growth factors that play a crucial role in tissue healing. Objective: To evaluate the efficacy of intra-articularly injected autologous PL in equine athletes with naturally occurring osteoarthritis. Animals and methods: Fifteen warmblood geldings aged 8–19 years with osteoarthritis of the distal interphalangeal joint were included in this study. They were randomly divided into two groups; 10 horses received intra-articular injections of PL and 5 of normal saline (controls). Before treatment, platelet-derived growth factor (PDGF) levels in basal plasma and prepared PL were estimated. Each joint was injected twice within a three-week period. Lameness was evaluated using the American Association of Equine Practitioners grading system, before treatment and 10 days after each intra-articular injection. Horses were examined fortnightly for one year. Radiographic examination was performed six months post-treatment. The generalized estimating equation test was used for statistical analysis. Results: Acceptable levels of PDGF were detected in PLs (mean ± SD: 258.0 ± 52.3 pg/ml). The majority of horses (9/10) responded positively to PL treatment presenting lower lameness grades (p < 0.0005) compared to controls 10 days after the second injection, and returned to normal athletic activity. Radiographs revealed no changes in osteoarthritis lesions six months after treatment. One year post-injections, however, all horses relapsed to their initial degree of lameness. Conclusion: Intra-articularly injected autologous PL is an efficient method for temporarily managing osteoarthritis of the distal interphalangeal joint in athletic horses.

Locally injected autologous platelet-rich plasma enhanced tissue perfusion and improved survival of long subdermal plexus skin flaps in dogs

OBJECTIVES Distal flap necrosis remains a major complication in subdermal plexus (random) skin flaps. Platelet-rich plasma (PRP) has been shown to improve the survival of ischemic random skin flaps in rats. The objective of this study was to evaluate the effect of locally injected autologous PRP on the survival of long (5:1 length-to-width ratio) subdermal plexus skin flaps in dogs. METHODS A 2x10 cm subdermal plexus skin flap was created bilaterally on the abdominal wall of six Beagle dogs. One randomly selected side received 2.5 ml of fresh auto-logous PRP injected evenly between sutures underneath the flap, whereas the other side was left untreated (control). Skin flap survival was evaluated macroscopically, histologically and by laser-Doppler flowmetry measurements of tissue perfusion. RESULTS Flap percentage survival on day 10 (96.3% versus 74.5%; p = 0.046) and tissue perfusion (p <0.036) were significantly higher in PRP-treated flaps compared with controls. Histologically, there was less oedema in PRP-treated flaps compared to controls (p = 0.01), whereas collagen production and angiogenesis did not differ significantly between the two groups. CLINICAL SIGNIFICANCE The use of locally injected autologous PRP increases tissue perfusion and improves the survival of long subdermal plexus skin flaps in dogs.

Naturally Occurring Isohexenylnaphthazarins and Wound Healing: Experimental Study in Dogs

Background: The healing efficacy of isohexenylnaphthazarins (IHN) has been well proved on chronic or contaminated wounds. Objective: To evaluate the wound healing activity of an experimental ointment containing IHN on acute and noncontaminated wounds in dogs. Methods: In each of six beagle dogs, four full-thickness skin defects were created bilaterally: one 2 × 2 cm defect on the lateral aspect of each arm for subjective evaluation, laser Doppler flowmetry (LDF), and planimetry and three 1.5 × 1.5 cm defects on opposite sides of the dorsal midline for histologic evaluation. Wounds on the left were treated with an ointment based on IHN and on the right with another based on petroleum jelly (Vaseline) and beeswax. Results: Wound size decreased significantly in both sides. The significantly increased percentage of epithelialization was higher (p = .0274) in the petroleum jelly–treated wounds on day 20. Tissue perfusion (LDF) increased significantly bilaterally in the center of the wound but only in the IHN-treated side cranial to the wound. Histologically, angiogenesis was significantly higher (p = .0431) on day 5 in the IHN-treated wounds compared with the petroleum jelly–treated wounds. Collagen production increased significantly bilaterally. Conclusion: The IHN-based ointment promoted some of the proliferative processes, but it did not enhance the overall wound healing of acute, surgically created wounds in dogs.

Markers of lipid peroxidation and α-tocopherol levels in the blood and neoplastic tissue of dogs with malignant mammary gland tumors.

BACKGROUND Excess reactive oxygen species due to oxidative stress and the ensuing lipid peroxidation are believed to be involved in mammary gland tumor (MGT) pathogenesis. OBJECTIVE The purpose of this study was to evaluate the extent of lipid peroxidation as evidenced by thiobarbituric acid-reactive substances (TBARS) formation, and the concentration of α-tocopherol as an inhibitor of lipid peroxidation, in blood and neoplastic tissue of dogs with malignant MGT. The correlation between inflammatory cell infiltration score and TBARS or α-tocopherol in MGT was also evaluated. METHODS Sixteen intact female dogs with malignant MGT and 12 clinically healthy and age/weight-matched controls were included in the study. In all dogs, serum TBARS, α-tocopherol, total cholesterol, and triglycerides were measured. Tissue TBARS and α-tocopherol levels were determined in 1 cm(3) sized tissue samples collected from MGT and adjacent, ipsilateral, normal mammary gland tissue from the 16 affected dogs. The degree of inflammatory cell tumor infiltration was evaluated histologically. RESULTS There were no statistically significant differences in serum levels of TBARS, α-tocopherol, total cholesterol, and triglycerides between dogs with and without malignant MGT. TBARS were significantly higher, whereas α-tocopherol was lower in neoplastic tissue when compared with normal mammary gland tissue. There was no correlation between TBARS or α-tocopherol concentration and the inflammatory cell infiltration score in neoplastic tissue. CONCLUSION The increased level of TBARS suggests oxidative stress induction in canine malignant MGT. The origin of this phenomenon is not clear, as a potential oxidative burst could not be attributed to inflammatory cells infiltrating the tumors.

Evaluation of blood T-lymphocyte subpopulations involved in host cellular immunity in dogs with mammary cancer

Cancer-bearing patients are often immunosuppressed. In dogs with mammary or other cancers, various alterations in blood cell populations involved in host cellular immunity have been reported; among these cell populations some T-lymphocyte subsets play an important role against cancer. The purpose of the present study was to investigate any alterations in circulating T-lymphocyte subpopulations involved in cellular immunity in bitches with mammary cancer, in comparison to age-matched healthy intact bitches. Twenty eight dogs with mammary cancer and 14 control dogs were included in this study. Twelve out of the 28 bitches had mammary cancer of clinical stage II and 16/28 of stage III. Histological examination revealed that 23/28 animals had carcinomas, 3/28 sarcomas and 2/28 carcinosarcomas. White blood cell, neutrophil and lymphocyte absolute numbers were measured by complete blood count. Furthermore, blood T-lymphocyte population (CD3+) and the subpopulations CD4+, CD8+ and CD5low+ were assessed by flow cytometry. White blood cell and neutrophil but not lymphocyte absolute numbers were higher (P=0.003 and P=0.001, respectively) in cancer patients than controls. Flow cytometric analysis revealed that the relative percentage of T-lymphocytes (CD3+) and of CD4+, CD8+ subpopulations was lower (the CD4+/CD8+ ratio was higher), whereas the percentage of CD5low+ T-cells was higher, in dogs with cancer compared to controls; however, a statistically significant difference was found only in the case of CD8+ T-cells (P=0.014), whereas in the case of the CD4+/CD8+ ratio the difference almost reached statistical significance (P=0.059). Based on these findings, it can be suggested that, although the absolute number of blood lymphocytes is unchanged, the relative percentages of T-lymphocyte subpopulations involved in host cell-mediated immunity are altered, but only cytotoxic CD8+ T-cells are significantly suppressed, in dogs with mammary cancer of clinical stage II or III compared to age-matched healthy controls.

Adipose-derived stromal vascular fraction aids epithelialisation and angiogenesis in an animal model

OBJECTIVE Limited data exist regarding the correlation between adipose-derived stromal vascular fraction (SVF) and wound healing. The aim of this study was to investigate the direct effect of intradermally injected SVF on full-thickness cutaneous wounds in a murine model. METHOD Wistar rats were divided into three groups (A, B and C) according to their day of euthanasia (day 7, 16 and 21). Inguinal fat pad was excised and SVF enzymatically extracted. Full-thickness cutaneous wounds were created on each side of the dorsum; SVF injected intradermally at one side while the contralateral wound served as control receiving normal saline. Postoperatively, evaluation of wound healing was performed by planimetry (percentages of wound contraction, epithelialisation and total wound healing) on days 0, 3, 5, 7, 10, 13, 16 and 21, and histology and immunochemistry (cellular infiltration score, collagen production score, neoangiogenesis and epithelial thickness) on days 7, 16 and 21. RESULTS Despite the high rate of wound contraction, it was significantly lower in the SVF-treated wounds on day 21 (p=0.037). On days 13, 16 and 21, the percentages of epithelialisation were higher in the SVF-treated wounds compared with control wounds (p=0.026, p=0.048 and p=0.05, respectively). Histologically, the number of new vessels was significantly higher in the SVF-treated wounds compared with controls on days seven (p=0.028) and 16 (p=0.027). This was also confirmed by immunohistochemistry. No significant differences were found between treated and control wounds regarding cellular infiltration score, collagen production score and epithelial thickness. CONCLUSION Data indicate that intradermally injected SVF increases angiogenesis and enhances epithelialisation in full-thickness cutaneous wounds in rats.