Effects of Growth Factors and L-Arginine on Ischemic Skin Flaps in Rats

This study determined the effect of the polypeptide growth factors transforming growth factor-beta (TGF-β), insulin-like growth factor-I (IGF-I), and growth hormone (GH) alone and in combination with dietary L-Arginine HCL (ARG) on skin flap survival in rats. Caudally based dorsal skin flaps were created in 110 Sprague-Dawley rats. The rats were randomly assigned into three treatment groups, based on drinking water supplementation. Group 1 (n = 50) received ARG in their drinking water, group 2 (n = 50) received tap water alone, and group 3 (n = 10) received N-omega-nitro-L-arginine (L-NA) and hydralazine. Groups 1 and 2 were divided into subgroups of 10 rats each based on treatment with either: TGF-β, IGF-I, GH, or IGF-I + GH. All subgroups that received GH had significantly greater ( P <.0001) median body weight gains when compared with subgroups not receiving GH. L-arginine HCL when added to IGF-I negated the positive effects of IGF-I on both flap survival and weight gain. Although the rats in all subgroups from groups 1 and 2 had an increase in mean percent skin flap survival when compared with the water alone subgroup, only rats receiving IGF-I, or the combination of ARG with either TGF-β or GH, had statistically significant enhanced skin flap survival. Rats in group 3 did not show an increase in skin flap survival when compared with the control subgroup.     

Thoracodorsal and Caudal Superficial Epigastric Axial Pattern Skin Flaps in Cats

Nonselective angiography, selective angiography, and gross dissection of 15 cadavers were performed to delineate direct cutaneous arteries in the cat. The omocervical, deep circumflex iliac, thoracodorsal, and caudal superficial epigastric arteries were identified by nonselective angiography. Selective angiography and gross dissection allowed assessment of the origin and vascular territories of the thoracodorsal and caudal superficial epigastric arteries. Orthotopic and heterotopic transfers of thoracodorsal and caudal superficial epigastric island flaps were performed on eight cats. All flaps were successful although areas of necrosis at the caudodistal tips were evident in most of the thoracodorsal flaps. The rotated thoracodorsal flaps extended to the carpi. Caudal superficial epigastric flaps enabled coverage to the metatarsus. Seroma formation and partial dehiscence were minor complications.     

Xylenol Orange as a Vital Stain to Determine the Viability of Skin Flaps in Dogs

Intravenous injection of xylenol orange results in generalized violet staining of vascularized skin. The precision of xylenol orange vital staining was compared to fluorescein sodium vital staining and to assessment of skin flap viability by visual observation (color). Skin flaps in the experimental dogs were evaluated by each method at 0, 24, 72, and 120 hours after surgery and subsequently compared to the length of skin flap that remained viable at 216 hours. No significant differences between methods were found at any time interval; however, assessment of skin flap viability was significantly more precise at 24,72, and 120 hours in comparison to the 0 hour assessments. The use of xylenol orange to assess vascular integrity of skin is precise, but no advantage over fluorescein sodium vital staining or assessment by visual observation was noted.     

Skin Fold Advancement Flaps for Closing Large Sternal and Inguinal Wounds in Cats and Dogs

Skin fold advancement flaps can be created from the elbow and flank folds to close large wounds in the pectoral and inguinal regions of cats and dogs, respectively. The attachments of the laterally facing (outer) and medially facing (inner) layers of the skin fold to the adjacent limb are divided to produce a U-shaped pedicle graft attached to the trunk. This mobilizes skin that can be advanced over large wounds involving the ventral chest or abdomen, or both. The use of skin fold advancement flaps enables direct closure of large skin defects without undue tension and without compromising the mobility of the adjacent limb.     

浇泼剂对小鼠皮肤组织结构的影响

给小白鼠背部按一定剂量浇泼阿维菌素浇泼剂及倍硫磷浇泼剂，于８ｈ、２４ｈ、３５ｈ将用药小鼠处死，背部（用药部位）取材，分别进行光学显微镜及透射电子显微镜观察。结果，阿维菌素浇泼剂按０．００４ｍｌ／１０ｇ浇泼，约有２０％的表皮上皮细胞角化及脱落，而按０．１ｍｌ／１０ｇ浇泼，约有４０％的表皮上皮细胞完全角化及脱落、坏死，真皮胶原纤维减少、疏松、染色较浅泼有充血和出血现象；毛囊外根鞘上皮细胞浆内出现大量空泡、间质细胞内质网有轻度的扩张。倍硫磷浇泼剂按０．０４１３ｍｌ／１０ｇ浇泼，可见上皮细胞轻度角化、真皮胶原纤维淡染、疏松并有空泡变性及散在的红细胞；毛囊外根鞘及内根鞘细胞浆内有大量空泡、间质中胶原纤维染色不均。按０．１ｍｌ／１０ｇ背部浇泼透皮吸收促进剂，经不同时间取材进行光镜及电镜观察，未发现明显的组织结构变化。     

Rapid Tissue Expansion for the Development of Rotational Skin Flaps in the Distal Portion of the Hindlimb of Dogs: An Experimental Study

In phase I, tissue expanders were implanted subcutaneously over the lateral crural region of four dogs. The expanders were inflated daily to maintain a constant intraluminal pressure for 7 days. All animals tolerated the pressurized expanders well. Some animal patient discomfort was associated with repeated injections into the subcutaneous filling port. One dog developed a limited area of tissue loss and exposure of the expander. Tissue response to the expanders included epidermal hyperplasia, dermal collagen compression with early fibroplasia, and subcutaneous granulation tissue formation adjacent to the expander pocket. In phase II, a second group of four dogs underwent rapid skin expansion over 7 days. The pressure applied to the expanding skin was determined daily and adjusted to approximate the value reported for capillary pressure in the dog. Tissue discoloration occurred in two dogs, suggestive of impaired circulation. Skin flaps were developed from expanded skin and rotated over the talocrural region. Wound dehiscence occurred along the distal flap margin in three phase II dogs. These wounds healed by second intention. Branches of the caudal saphenous artery were identified, using angiography, as the primary blood supply to the skin flaps.     

不同消化酶对羊驼皮肤黑素细胞分离的影响

本研究旨在探讨羊驼皮肤黑素细胞的分离、培养及鉴定方法,为进一步研究色素沉积提供合适的细胞模型。取1~3岁的青年羊驼皮肤,用胰酶、胰酶∶EDTA、DispaseⅡ酶3种不同的消化酶消化羊驼皮肤,再用胰酶∶EDTA消化,分离得到羊驼黑素细胞,接种于多种促进黑素细胞生长的营养成分DMEM/F12培养基中,通过观察黑素细胞的生长、细胞接种数和细胞贴壁数检验黑素细胞的纯度。结果表明,DispaseⅡ组处理的羊驼皮肤,分离得到的黑素细胞明显多于其它2个组(P＜0.01)。综上所述,选用DispaseⅡ酶作为分离羊驼皮肤的消化酶,可获得较纯的黑素细胞。     

The Effect of Occlusive and Semi-Occlusive Dressings on the Healing of Acute Full-Thickness Skin Wounds on the Forelimbs of Dogs

This project compared the effects of hydrocolloid (HC) and hydrogel (HG) occlusive dressings and a polyethylene (PE) semi-occlusive dressing on the healing of acute full-thickness skin wounds on the forelimbs of 10 dogs. All treatments resulted in a similar degree of healing at postoperative days 4 and 7. No significant differences existed in the number of wounds that were more than 90% healed at postoperative day 28 between the group treated with the HG dressing and the group treated with the PE dressing. There were significantly fewer wounds more than 90% healed at postoperative day 28 in the group treated with the HC dressing. Wounds under the HG dressing had the largest mean percentage of contraction at postoperative days 21 and 28. Wounds under the HG dressing also had the largest contraction/re-epithelialization ratio (postoperative days 21 and 28) compared with wounds under the PE and HC dressings. Wounds under the PE dressing had a significantly higher mean percentage of re-epithelialization than wounds under both occlusive dressings on postoperative days 14, 21, and 28. Wounds under the two occlusive dressings had exuberant granulation tissue present more often than wounds under the PE dressing. The two occlusive dressings had significantly higher bacterial counts on wounds compared with wounds under the PE dressing; analysis of variance (ANOVA), P = .0008. Wounds under the HC dressing showed the poorest healing in all parameters.     

Combination Allopurinol and Antimony Treatment versus Antimony Alone and Allopurinol Alone in the Treatment of Canine Leishmaniasis (96 Cases)

The aim of the present study was to evaluate the long-term clinical outcome for dogs with leishmaniasis that were treated with 3 different protocols: combined treatment with antimony and allopurinol, antimony alone, or allopurinol alone. Ninety-six dogs included in this study were determined to have leishmaniasis on the basis of (1) clinical features, (2) identification of the parasite in smears of lymph node, bone marrow aspirates, or skin biopsies, and (3) specific immunofluorescent assay. Three groups of dogs were defined: 45 dogs (group 1) were treated with antimony (100 mg/kg s.c. q24h) given concurrently for 1 month with allopurinol (15 mg/kg p.o. q12h), and then allopurinol alone for 8 months at the same dosage; 40 dogs (group 2) were treated with antimony alone according to the manufacturer's instructions (200 mg/kg s.c. q24h at 2-day intervals for 3-6 months); and 11 dogs (group 3) were treated with allopurinol alone (15 mg/kg p.o. q12h for 1-20 months). Information concerning signalment, history, physical examination findings, serologic testing and number of dogs becoming seronegative, outcome for each treated dog (clinical cure versus failure), and long-term survival were recorded. The numbers of the clinical cures versus failures were significantly different among the 3 groups (chi2 = 17.77, P < .001), between groups 1 and 2 (chi2 = 8.02, P < .01), between groups 2 and 3 (chi2 = 11.00, P < .01), and between groups 1 and 3 (chi2 = 16.52, P < .001). No significant difference between groups 1 and 2 was noted in the type of failure (relapse or death), serologic test results, and number of survival years (chi2 = 2.79, P > .05). The results of the present study indicate that antimony in combination with allopurinol produces better results than antimony alone or allopurinol alone for the treatment of the canine leishmaniasis. With combination treatment, duration of treatment with antimony is shorter and long-term administration of allopurinol is well tolerated.     

诺氟沙星对两种鲟体内SOD活力影响的比较研究

将诺氟沙星按照0、20、40、60、80和100 mg/kg浓度,对小体鲟及史氏鲟连续口服给药5 d,停药2 d后对其血浆及肝脏组织中过氧化物岐化酶(SOD)活力进行测定,以期掌握不同诺氟沙星给药浓度下,两种鲟两种组织中SOD活力变化趋势,并探讨评价该药在鲟养殖过程中使用的最适剂量,以及对鱼类肝脏的损伤情况。试验结果表明,两种鲟两种组织内均含有一定量的SOD酶,且在对照组及所有给药组肝脏中酶活力均高于血浆中。不同给药浓度下,两种鲟两种组织中SOD活力变化均呈现规律的先受诱导升高,而后被抑制降低的变化趋势,且在40 mg/kg给药浓度组达到最大值。血浆中SOD活力受给药浓度影响较小,起伏较平稳,在40 mg/kg给药浓度组史氏鲟血浆中SOD值高于小体鲟,而其他组别均为小体鲟较高。而肝脏中SOD活力变化较剧烈,且在对照组、诱导最高SOD活力的40 mg/kg给药浓度组和最高给药浓度组,小体鲟均高于史氏鲟,且小体鲟肝脏中SOD在40 mg/kg给药浓度组活力值极高,形成一个尖锐的峰值。结果表明,诺氟沙星对两种鲟给药浓度为30~50 mg/kg时,既能使药效最好而又不会对肝脏产生明显的损伤。     

Effects of Epidural Anesthesia on Microcirculatory Blood Flow in Free Medial Saphenous Fasciocutaneous Flaps in Dogs

OBJECTIVE: To assess the effects of epidural anesthesia using lidocaine on microcirculatory blood flow, volume, and velocity in free fasciocutaneous flaps in dogs. Study Design-In vivo experimental investigation. Animal Population-Ten adult dogs weighing 20 to 25 kg. METHODS: A medial saphenous fasciocutaneous free flap was removed and an orthotopic transfer was performed by anastomosing the primary flap vessels back to the medial saphenous vessels. Blood flow (mL(LD)/min/100 g), volume (%volume or tissue hematocrit) and velocity (mm/s) in the flap were recorded throughout the procedure. After epidural anesthesia, blood flow, volume, and velocity values were again recorded. RESULTS: Microcirculatory blood flow, volume, and velocity, as measured by a laser-Doppler flowmeter, failed to reveal any significant changes over time. Immediately after epidural anesthesia, mean arterial pressure was significantly reduced and remained depressed throughout the experimental procedure. CONCLUSIONS: Epidural anesthesia combined with general anesthesia does not improve microcirculatory flow in free flaps in the pelvic limbs of dogs. No significant change in blood flow to the medial saphenous fasciocutaneous free flap occurred after division and anastomosis of the vascular pedicle. CLINICAL RELEVANCE: We recommend that epidural anesthesia with 2% lidocaine be used with caution in dogs undergoing microvascular free-flap transfer.     

The Enhancing Effects of Hyperbaric Oxygen on Mouse Skin Carcinogenesis

The effects of hyperbaric oxygen (HBO) on mouse skin two-stage chemical carcinogenesis were examined. Six-week-old inbred CD-1 female mice were divided into the following five groups: group 1, normoxia and application of 25 nmol 7,12-dimethylbenz[a]anthracene (DMBA) and 8.5 nmol 12-O-tetradecanoylphorbol-13-acetate (TPA) (n=19); group 2, HBO and DMBA/TPA (n=21); group 3, HBO and DMBA/acetone (n=3); group 4, normoxia and acetone (n=3); and group 5, non-treatment group (n=5). HBO was started at the same time as DMBA. Mice were euthanized at 23 weeks after the start of the experiment. Mice in group 2 showed the occurrence of tumors at 8 weeks after the beginning of the experiment, while the occurrence of tumors in mice in group 1 was observed beginning at 9 weeks. There was a difference in occurrence among low-grade papillomas, high-grade papillomas and SCCs in both groups 1 and 2 by the χ²-test at end of the experiment (p<0.05). The Ki-67 labeling indices of tumors revealed that the percentages of positive cells in low-grade papillomas in groups 1 and 2 were 15.27 ± 2.54% and 29.67 ± 2.82%, respectively (p<0.01). The results suggested that the tumors in group 2, which was treated with HBO, were more progressive than those in group 1, which was not treated with HBO. In this study, HBO accelerated tumor cell proliferation and advanced tumor progression in skin carcinogenesis by DMBA/TPA.     

不同微生态制剂对蛋鸡机体超氧化物歧化酶调节机制的影响

本试验旨在研究不同微生态制剂对蛋鸡机体超氧化物歧化酶(SOD)调节机制的影响。选择360只健康的海兰褐蛋鸡,随机分成5组,每组3个重复,每个重复24只。对照组(Ⅰ组)饲喂基础饲粮,试验组(Ⅱ、Ⅲ、Ⅳ、Ⅴ组)分别在基础饲粮中添加0.5%中药乳酸菌、0.25%乳酸菌制剂+0.25%中药红曲霉制剂、0.5%乳酸菌制剂和0.5%中药红曲霉制剂。试验期为79 d。结果表明:1)与对照组相比,试验组中蛋鸡血清总超氧化物歧化酶(T-SOD)活性显著提高(P0.05),Ⅱ、Ⅲ和Ⅳ组蛋黄中T-SOD活性显著提高(P0.05)。2)与对照组相比,Ⅱ组蛋鸡肝脏中SOD1 m RNA的表达量显著提高(P0.05),Ⅱ、Ⅳ和Ⅴ组的蛋鸡肝脏中SOD2 m RNA表达量显著提高(P0.05)。由此可见,饲粮中添加上述微生态制剂能调节蛋鸡机体SOD机制,以添加0.5%中药乳酸菌制剂效果最好。     

日粮硒水平对肉仔鸡成活率和生长性能的影响

通过饲养对比试验,研究向日粮中添加不同剂量的微量元素硒对肉仔鸡成活率和生长性能的影响。研究结果表明,肉仔鸡在采食不同硒水平日粮(0.025~0.200 mg/kg)时,对生长性能、饲料转化率和成活率均呈现不同程度的提高作用,尤以日粮中硒的添加量为0.125 mg/kg时,能显著提高生长性能和成活率。     

铁与维生素A水平对小鼠胚胎存活的影响

试验探讨了铁与维生素A水平对小鼠胚胎存活的影响。选取21日龄昆明种小鼠,饲喂商品日粮2周,随后采用试验饲粮饲喂第11周时,进行交配。此后选有阴栓的小鼠随机分为1个对照组和9个处理组(采用2因素3水平完全随试验设计,铁添加水平为3.5、35、175mg/kg,维生素A水平为400、4000、20000IU/kg),每组分3个重复,每个重复6只。结果表明:妊娠3、6、18d,与对照组相比,35mg/kgFe+4000IU/kg维生素A组胚胎存活率分别提高了25.6%(P<0.05)、9.2%(P<0.05)、46.6%(P<0.05)。适量的铁和维生素A水平有利于胚胎的发育,高铁会降低胚胎的存活率。铁与维生素A对胚胎的存活率的影响存在互作效应(P<0.05)。     

Misapplication of Subcutaneous Pedicle Flaps in the Dog

Subcutaneous pedicle flaps were created in 21 dogs, 1) with an intact underlying panniculus muscle, 2) with a severed panniculus muscle, and 3) devoid of an underlying panniculus muscle. The survival rates of the resultant grafts were evaluated over a minimum of ten days. All 19 subcutaneous pedicle flaps survived when the underlying panniculus muscle was intact. Nineteen of 23 flaps with a severed panniculus muscle, however, developed necrosis. The survival rates between these two groups were significantly different (p < 0.01). Eight of 14 flaps developed without an underlying panniculus muscle underwent necrosis. Their survival rate was significantly different from flaps with an intact panniculus muscle (p < 0.01) but not significantly different from flaps without an intact panniculus muscle (p < 0.1). Four of 23 subcutaneous pedicle flaps with severed panniculus muscles and six of 14 flaps without an underlying panniculus muscle survived, despite apparent vascular compromise. Six of these grafts survived by accidental incorporation of a direct cutaneous artery and vein beneath the graft. Results from this experiment indicate that subcutaneous pedicle flap development in the dog has a high incidence of necrosis unless a panniculus pedicle to the overlying skin is preserved. As such, they have no advantage in the dog over safer and simpler closure techniques, which preserve the cutaneous circulation.     

Effects of Acute Hyperventilation on Serum Potassium in the Dog

The effects of increasing respiratory rates on arterial pH, PaCO2, HCO3, and potassium (K) were measured in normal anesthetized dogs. Hyperventilation resulted in increased pH, decreased PaCO2, decreased HCO3, and decreased K compared with those parameters in spontaneously breathing dogs. The changes were related quantitatively: each 10 mmHg decrease in PaCO2 was associated with a pH increase of 0.1, a HCO3 decrease of 2.0 mEq/L, and a K decrease of 0.4 mEq/L. There were no cardiac arrhythmias or clinical signs of hypokalemia. After termination of hyperventilation, serum K was slower to return to control values than PaCO2. The ratio of the duration of hyperventilation to the time required for return of serum K to control was 0.67.