The place of D-dimer and L-lactate levels in the early diagnosis of acute mesenteric ischemia.

INTRODUCTION: Acute mesenteric ischemia (AMI) is an abdominal-vascular emergency which is rare and has high mortality rates (60-80 %) due to late diagnosis (1-3). Although it is known that extravascular reasons like intestinal intussusception, volvulus, strangulated hernias and obstructions can cause intestinal gangrene, these are rarely the cause of AMI (1). MATERIALS AND METHODS: In this study, we used male Wistar-Albino rats weighing 250-300 grams obtained from Pamukkale University Experimental Research Laboratory. Animals were exposed to light-dark cycles for 12 hours and had free access to food and water. They were kept in cages for 7 days to stabilise their intestinal flora. In animals of group I, nothing was made other than taking 0.5 ml blood intracardially. In other animals, abdomen was reached with midline laparotomy and superior mesenteric artery (SMA) was located. In group II (operative control group), SMA was isolated and manipulated but was not ligated. In Group III (intestinal ischemia group), SMAwas isolated and ligated with 3/0 silk tie distally to the aorta. After this process, intestinal ischemia was achieved which was confirmed by paleness and pulselessness of intestines, caecum and right colon. Later on, abdomen was closed with double 3/0 polyglactin sutures. At postoperative 1st, 4th and 6th hours 0.5 ml blood was taken intracardially from the animals in groups II and III in order to quantify D-dimer and L-lactate levels. LABORATORY TESTS: D-dimer: Blood samples which were put into tubes containing sodium citrate, were seperated from plasma with centrifugation at 4000 rpm for 7 minutes.L-lactate: Blood L-lactate levels were determined from blood taken into capillary tubes with the help of immobilised enzyme electrode technology using YSI 1500 Sport portative lactate analyzer (Yellow Springs Instruments Inc., Ohio-USA). HISTOPATHOLOGIC VERIFICATION: Two cm long intestinal samples were taken from animals in which SMA was ligated in order to achieve mesenteric ischemia and these samples were fixed in 10 % formol. DISCUSSION: As a result, in rats with SMA occlusion serum D-dimer levels were not increased significantly when compared either in the group or with the basal values of the control group and values in operative control group. Therefore, it is concluded that D-dimer is not a useful marker for early diagnosis of AMI. On the other hand, it is revealed that blood L-lactate levels began to increase significantly following 4th hour of mesenteric ischemia and it is shown that this increase continued at the 6th hour. In addition, considering the utmost importance of the early diagnosis in patients with the clinical suspicion of AMI, L-lactate seems to be a suitable marker to use in emergency departments because it is achieved with a portable device that gives fast and accurate results. Nevertheless, our results are need to be supported by clinical studies with larger patient series (Tab. 2, Fig. 11, Ref. 39).

Local rhBMP-2 injection after drill-hole injury in rats: does it have systemic effects?

The aim of this study is to investigate the histopathological findings of drill hole healing and interactions of parathyroid hormone (PTH), β-catenin and transcription factor-4 (TCF7L2/Tcf-4) after local application of recombinant human bone morphogenic protein-2 (rhBMP-2). Sprague Dawley rats were used in two groups of ‘femoral cortex hole model’. In the non-treated group, a hole was opened with a 3 mm K-wire in the distal and mid third junction of the right femur. In the treated group, local rhBMP-2 protein was injected into the similar femoral hole. Sterile 18M H2O was injected into the femoral hole at contralateral femur. There was more subperiosteal membranous bone reaction in the group treated with rhBMP-2 injection compared to the non-treated group. This was also proven immunohistochemically in both ipsilateral and contralateral femur with increased anti bone morphogenic protein-2 (anti BMP-2) expression. Moreover, there was an increased subperiosteal reaction at the contralateral femur. Also, in the treated group, PTH expression was increased in cells that form callus, and nuclear beta-catenin expression was increased in chondrocytes of periosteal ossification. Future studies should try to find whether the effects of rhBMP-2 on PTH and Wnt signaling pathway changes with different fracture models, also the systemic effects of local rhBMP-2 application should be investigated.

Reticulohistiocytosis: different dermatoscopic faces and a good response to methotrexate treatment.

The reticulohistiocytoses are a rare group of non-Langerhans cell histiocytic disorders. Recently, dermatoscopic features have been reported for some of the xanthomatous disorders. We report a case of diffuse cutaneous reticulohistiocytosis with 29 reticulohistiocytomas. On dermatoscopy of these lesions, we saw three typical features: a homogeneous pattern with various shades of yellow (defined previously as a 'setting-sun' pattern), brown reticular structures, and central white scar-like patches and streaks. The setting-sun pattern was most commonly seen in combination with brown reticular structures. In four lesions, brown reticular structures surrounded a central white scar-like patch resembling that of a dermatofibroma. However, the presence of the setting-sun pattern in the background gave a different hue to that of the peripheral network seen in a dermatofibroma. A marked clinical improvement was associated with 6 months of systemic methotrexate treatment. Dermatoscopy may aid in the diagnosis of xanthomatous diseases. For this patient, methotrexate was beneficial.

Bypassing melanocyte senescence by beta-catenin: a novel way to promote melanoma.

The Wnt/beta-catenin signaling pathway plays a key role in several cellular functions during embryonic development and adult homeostasis. The deregulation of this pathway may lead to the development of cancer, including melanoma. Deregulation of the Wnt/beta-catenin pathway occurs through either the induction/repression of, or specific mutations in, various members of this signaling pathway; this results in the stabilization of beta-catenin and its translocation from the cytoplasm to the nucleus, where it regulates transcription. Although nuclear beta-catenin is clearly involved in malignant transformation, the mechanism by which it exerts its effects remains elusive. This review focuses on the molecular and cellular mechanisms that are driven by beta-catenin and lead to melanocyte transformation. In particular, we describe how beta-catenin induces melanocyte immortalization, a novel activity of this multifunction protein. Finally, we discuss how beta-catenin-induced immortalization can cooperate with MAPKinase pathways to produce melanoma.

The effect of the sun on expression of beta-catenin, p16 and cyclin d1 proteins in melanocytic lesions.

BACKGROUND: The tumour suppressor gene product, p16, is often inactivated during melanoma malignant progression. Although the importance of p16 in melanomas is well documented, its relationship with cyclin D1, beta-catenin and ultraviolet radiation (UVR) remains unclear. AIM: To determine the role of these cell cycle-related proteins and high-risk sun exposure in the biological behaviour of melanocytic lesions. METHODS: We used immunohistochemistry to examine 28 melanocytic naevi (MN; 9 congenital and 19 acquired types) and 24 primary cutaneous malignant melanomas (CMM; 19 nodular melanomas, 3 lentigo maligna melanomas, 1 acral lentiginous melanoma and 1 superficial spreading melanoma) for the presence of p16, cyclin D1 and beta-catenin. The melanocytic lesions were classified into two groups to examine the effects of UVR on these three proteins: high risk of sun exposure (chronically sun damaged; CSD), or low risk of sun exposure (nonchronically sun damaged; non-CSD). We evaluated the relationship between the production of these proteins and the histopathological and clinical characteristics of the lesions. RESULTS: Production of p16 was repressed in most CMM, but not in MN (P < 0.0001). Cyclin D1 was overproduced in CMM but not in MN, and beta-catenin was frequently overproduced both in MN and CMM. Overproduction of beta-catenin was not common in CSD melanocytic lesions, but was more frequent in non-CSD melanocytic lesions (P = 0.027). CONCLUSION: An immunohistochemical panel including melanocytic markers enriched by p16 and cyclin D1 could be used to differentiate some borderline melanocytic lesions. In addition, the Wnt/beta-catenin pathway was more frequently activated in non-CSD than in CSD melanocytic lesions.

Antithrombin III Prevents Early Bacterial Translocation in Burn Injury.

We experimentally studied the effects of antithrombin III (AT III) on bacterial translocation (BT) and intestinal morphology in the early period of burn injury. For this aim, 30 male albino rats were used. A sham burn group (group 1, no. 10) was exposed to 21 °C water. A burn group (group 2, no. 10) and a burn + AT III group (group 3, no. 10) were exposed to 95 °C water for 10 sec, producing full-thickness burn in 30% of the total body surface area. In group 3 the rats received 250 U/kg AT III via the right jugular vein, 15 min before burn injury. One ml 0.9% NaCl was given as a placebo in group 1 and in two rats by the same route. All group 3 rats were sacrificed on day 2 post-burn using an overdose anaesthetic. Cultures of the mesenteric lymph nodes, liver, spleen, blood, and caecal contents were performed. Histopathological examinations, including polymorph nuclear leukocyte (PNL) infiltration and villus morphologies, were qualitatively evaluated on the resected distal ileal segment. The incidence of BT was 1/10 (10%) in group 1, 7/10 (70%) in group 2, and 1/10 (10%) in group 3. A significant increase in BT incidence was observed in group 2 compared with groups 1 and 3 (p = 0.02), while a significant decrease in BT incidence was found in group 3 rats with AT III treatment. Although the PNL infiltration rate was reduced by AT III treatment, a significant decrease was not found compared with group 2 (50% and 90%, respectively). On the other hand, the villus degeneration rate was significantly reduced by AT III treatment compared with group 2 (30% and 90%, respectively). These results suggest that the incidence of BT was enhanced by the burn injury. AT III decreased the incidence of BT in the early period of burn injury. We conclude that AT III can be effectively used to protect from intestinal mucosal injury and to prevent bacterial translocation, especially in early post-burn period.

Antithrombin III reduces renal ischemia-reperfusion injury in rats.

Few studies have pointed out the relationship between ischemia-reperfusion (IR) injury and the coagulation system. Antithrombin III (AT) has anti-inflammatory effects in IR injury. We investigated the effect of AT supplementation on renal IR injury in rats achieved by clamping of the left renal pedicle for 60 min and subsequent 24-h reperfusion after right nephrectomy. Sprague-Dawley rats were divided into three groups: sham-operated (no IR injury), ischemic controls, and an AT-treated group (250 U/kg before reperfusion). Creatinine values, tissue malondialdehyde (MDA) levels, myeloperoxidase (MPO) activity, and histopathological damage were investigated after 24 h of reperfusion. In addition, the 7-day survival rates in each group were evaluated. Creatinine and MDA levels and MPO activity were significantly elevated and histopathological damage was more severe in controls than in the sham group (P<0.05). Creatinine and MDA levels and MPO activity were significantly lower and there was less histopathological damage in the AT group than in controls. Accumulation of lipid peroxidation products and neutrophils were significantly inhibited by AT treatment. We conclude that AT may attenuate renal IR injury in rats.

Inflammatory myofibroblastic tumor of small bowel wall in childhood: Report of a case and a review of the literature.

Benign intestinal tumors are rare in children, however we describe an inflammatory myofibroblastic tumor (IMT) of the jejunum in a 2-year-old girl who presented with an intestinal obstruction. During laparotomy, an annular mass around the jejunum was resected, from which a histological diagnosis of IMT was made. A review of the literature for this rare entity emphasizes the importance of histological confirmation of its benign nature. Because of the risk of local recurrence, IMT cases should have a long-term follow up.

Whipple's disease confined to the central nervous system: case report and review of the literature.

Whipple's disease confined exclusively to the CNS without systemic involvement appears to be very rare, with only 8 cases reported in the literature. We present here a further case of primary cerebral Whipple's disease in which the neurological symptoms were seen in the absence of systemic involvement and emphasize the importance of diagnosing this treatable disease.