Analysis of the Effects of an Unconventional Rolling Process under Cumulative Plastic Deformation Conditions.

This article presents the results of research carried out on an experimental rolling mill with axial, cyclic movement of rolls (RCMR). The device was made on the basis of an unconventional technical solution for the movement of shaping tools and equipped with a complete measuring system recording all the parameters of the process. The research was conducted on selected copper alloys CuFe2 and CuCr0.6. Rolling tests in the RCMR process were carried out for rolling speeds vr = 3.1 × 10-3, 6.3 × 10-3 and 9.4 × 10-3 m/s, which correspond to the rotational speed of the rollers at ω = 1, 2 and 3 rpm for an active diameter of the rollers = 60 mm. In testing the thermal effects of the process, the rolling speed ω = 0.7 rpm was also used. A constant value of the frequency of axial movement of the rollers f = 1 Hz and the amplitude of the displacement of the rollers A = 0.8 mm were assumed. The rolling process for the strands was carried out in six culverts using the average relative crush in the passage of Δh = 15%. Conventional rolling tests were carried out to compare rolling processes, and the obtained data formed the basis for assessing the strain intensity and identifying local deformation zones in the RCMR rolling process. The waveforms of rolling pressures, intensity and non-uniformity of deformation, and increase in the temperature of the strip surface in subsequent culverts were compared with the results obtained in the conventional rolling process.

Evaluation of Early and Late Effects of Surgical Treatment of Early Hepatic Artery Thrombosis After Liver Transplantation.

BACKGROUND: Hepatic artery thrombosis (HAT) is the most severe vascular complication after liver transplantation and one of the major causes of early graft loss and mortality after transplantation. The number of retransplantations and recipient deaths can be decreased with an urgent thrombectomy of the hepatic artery. The aim of the study was to analyze the early and long-term outcomes of the surgical revascularization of early hepatic artery thrombosis after liver transplantation. METHODS: Four hundred eleven orthotopic liver transplantations in 380 patients were performed at our center between 2005 and 2020. A Doppler evaluation of the graft vessels patency was performed daily for the first 5 days after transplantation in all recipients. After angio-computed tomography confirmation, most of the cases of HAT qualified for surgical revascularization. RESULTS: Early HAT was diagnosed in 20 cases (4.9%), occurring most frequently between the first and third day after transplantation. Sixteen patients underwent revascularization surgery. Among them, in the early post-transplantation period, 4 died and 2 more had retransplantation. Of the remaining 10 recipients, 2 had no biliary complications, 1 had bile leakage, and 7 had common bile duct stenosis, all treated endoscopically. Among 4 nonoperated patients, 1 died and the other 2 had retransplantation in the early post-transplantation period; the last of these 4 recipients had bile duct stenosis. CONCLUSIONS: The urgent surgical revascularization in liver recipients with early HAT allows the avoidance of early retransplantation. However, these patients require intensified surveillance owing to the high risk of biliary complications that may affect shortened graft and patient survival.

A New Method of Testing the Dynamic Deformation of Metals.

This paper presents the characteristics of a modernized rotary hammer equipped with a new measuring system based on strain gauges for recording short-term signals. The stand makes it possible to carry out dynamic tensile and bending tests in the range of linear speed of the exciting element from 5 to 40 m/s. Initial tests of dynamic deformation and structural studies in the form of fractures carried out on a representative group of metallic materials allowed determining the correlation "strain rate-strain structure". The proposed new methodology of dynamic materials testing is an original achievement of the authors and may be an effective tool for assessing the properties of construction materials under conditions of dynamic deformation. In practice, the test results can be used to design the structures of energy-consuming elements of vehicles and aircraft load-bearing elements subjected to dynamic loads. Having an extensive database of results from dynamic tests will allow verifying the correctness of calculations of the structure with the use of the finite element method.

Apoptosis of tubular epithelial cells in preimplantation biopsies of kidney grafts with immediate, slow and delayed function.

BACKGROUND: Apoptosis is a form of cell death observed in kidney grafts as a result of ischemia/reperfusion injury. The aim of our prospective study was to analyze the intensity of apoptosis in kidney tubules after cold storage in respect to early and 12-month post-transplant graft function. MATERIAL/METHODS: The intensity of renal tubular apoptosis was estimated by TUNEL method in proximal and distal tubules in 72 pre-implantation kidney biopsies. Sixteen patients with biopsies that did not fulfill Banff 97 classification, with early acute rejection or early graft loss, were excluded. Early graft function was defined as IGF (N=17) when serum creatinine (sCr) was <264 µmol/l at 3(rd) postoperative day (POD); as SGF (N=20) when sCr >264 µmol/l and not more than 1 dialysis was performed; and as DGF (N=19) when more than 1 dialysis was done. RESULTS: The percentage of apoptotic cells was markedly higher in distal than in proximal tubules in all 3 groups. The percentage of apoptotic cells in distal tubules found was: 3.02% (1.03-5.00%) in IGF, 1.66% (0.92-2.39%) in SGF, and 1.76% (0.84-2.68%) in DGF; these differences were not significant. In the IGF group the mean percentage of apoptotic cells in distal tubule was higher than in the other groups (not statistically significant). The subgroups of patients with higher and lower than median (1.35%) apoptotic cell range in distal tubules had similar graft function at the 12-month follow-up. CONCLUSIONS: The enhancement of tubular epithelial cells apoptosis in kidney grafts after cold storage does not determine its early and later excretory function.

Intra-abdominal infections after simultaneous pancreas - kidney transplantation.

BACKGROUND: Intra-abdominal infections (IAI) are among the most common causes of pancreatic graft loss and recipient death in the early period after simultaneous pancreas - kidney transplantation (SPK). The aim of the study was to analyze risk factors and clinical consequences of IAI in SPK patients. MATERIAL/METHODS: Forty-six consecutive SPK performed from 2004 to 2010 were subjected to analysis. RESULTS: IAI developed in 10 recipients (21.7%). The group of recipients with IAI had a higher rate of patients that required transfusion of more than 2 blood units (90% vs. 47%, p=0.028) or relaparotomy (80% vs. 14%, p<0.001), in comparison with patients without IAI. Additionally, in patients with IAI, both delayed kidney graft function or primary kidney graft nonfunction (40% vs. 11%, p=0.001) and recipient death (40% vs. 3%, p=0.006) were more frequently observed. Logistic regression analysis revealed an increased risk of IAI development in patients who required early relaparotomy (OR=24.8, p<0.001), transfusion of more than 2 blood units (OR=12.6, p=0.02), or postoperative dialysis therapy (OR=14.1, p=0.003). CONCLUSIONS: Perioperative blood loss requiring transfusion and necessity of relaparotomy increase the risk of IAI after SPK. Development of IAI after SPK may result in impaired kidney graft function and increases patient mortality in the early postoperative period.

[Long-term consequences of surgical excision of cortisol producing adrenocortical adenoma]. / Odlegle nastepstwa chirurgicznego usuniecia gruczolaka kory nadnercza wytwarzajacego kortyzol.

INTRODUCTION: Surgical excision of adrenocortical tumour in patients with ACTH-independent Cushing syndrome gives a chance for their entire cure. However in some patients after adrenalectomy persistent arterial hypertension, obesity and diabetes mellitus is observed. The aim of the study was to analyse long term consequences of surgical excision of cortisol producing adrenocortical adenoma with a special attention on the influence of adrenalectomy on arterial blood pressure. MATERIAL AND METHODS: 15 patients (mean age 54 years) suffering from arterial hypertension (n = 15), obesity or overweight (n = 12) and diabetes mellitus (n = 7) were subjected to analysis. Mean follow up time was 45 months. RESULTS: Improvement of blood pressure control after unilateral adrenalectomy was observed in 66.7% of patients. The risk factor of no improvement of blood pressure control was BMI > 30.5 kg/m(2) (RR = 4.0 [1.07-14.90]). During the follow up period decrease of maximal values of systolic and diastolic blood pressure was observed (34 [17-50] and 25 [16-35] mm Hg respectively; p < 0.01). In the entire group of patients a 3.4 kg/m(2) decrease of BMI was observed p = 0.01. BMI decreased significantly (more than 1 kg/m(2)) in 66.7% of patients. Only in 2 patients a complete regression of diabetes was observed. 46.7% of patients required supplementation with adrenal steroids. 40% of patients reported a subjective withdrawal of all symptoms of the disease after surgery and 46.7% only partial remission. CONCLUSION: Surgical excision of cortisol producing adrenocortical adenoma results in improvement of blood pressure control and body weight reduction in a large percentage of patients with Cushing syndrome. Obesity before adrenalectomy is the factor that reduces a chance for improvement of blood pressure control after surgery.

[Case of malignant tumour phyllodes converting to fibrosarcoma]. / Przypadek zlosliwego guza lisciastego z konwersja do wlókniakomiesaka.

Tumour phyllodes is rare breast neoplasm. The majority arises in women between ages 35 and 55. Tumours phyllodes are composed of hypercellular mesenchymal stroma and epithelial elements. They are commonly classified as benign, rarely as borderline or malignant. Recurrences are observed in 8-36% patients and metastases--in 13-26%. There is a case of large (28 x 24 cm) malignant tumour phyllodes presented in the article. Mastectomy was performed. After surgical treatment of recurrent tumours (fibrosarcoma form) occurred two times during 1 year time. They were operated immediately. In spite of unfavorable prognostic features of the tumour (large size, malignant histological character) and recurrences, final therapeutic effect was good.

Rare normalization of blood pressure after unilateral adrenalectomy in 31 patients with Conn syndrome.

BACKGROUND: Adrenal tumor excision in patients with Conn syndrome is not always followed by normalization of blood pressure (BP). The aim of the study was to determine predictors of persistent hypertension during long-term observation after adrenalectomy. MATERIALS AND METHODS: Thirty-one patients (23 F and 8 M) with Conn syndrome and adrenal tumor subjected to unilateral adrenalectomy were included. The duration of hypertension ranged from 1 to 30 years and observation time from 1 to 10 years. RESULTS: Beneficial impact of adrenalectomy on BP control was found in 25 patients, including only 10 patients with BP normalization. Patients with normalization of BP were significantly younger [41 (36-46) vs 53 (48-57) years; p = 0.002] and had lower pulse BP [72 (56-89) vs 93(80-106) mmHg; p = 0.03]. Significant decline of maximal values of systolic and diastolic BP after surgery was observed [59 (47-72) and 29 (20-37) mmHg, respectively]. The analysis revealed that age over 50 years and pulse BP over 70 mmHg predict the persistence of hypertension after surgery. CONCLUSION: Normalization of BP after adrenalectomy is observed only in 32% of patients with Conn syndrome regardless the normalization of hypokalemia. BP normalization in long period observation was more frequently found in younger patients with lower pulse BP.

[Follicular thyroid tumor as a diagnostic and therapeutic problem]. / Guzek pecherzykowy tarczycy jako problem diagnostyczno-leczniczy.

Although the appearance of follicular thyroid tumors in the population is high, only a small part of them are malignant. Follicular tumors are built of follicular epithelial cells and are encapsulated. Cell atypia differentiates follicular adenoma from cancer. Follicular cancer is characterized by vascular invasion and causes metastases through blood vessels, mainly to lungs and bones. In the diagnosis of follicular thyroid neoplasm, pathological examination of postoperative material plays a leading role. In diagnosis before surgical treatment, physical examination, ultrasound (USG), and fine needle aspiration biopsy (FNAB) are of great importance. The choice of treatment in patients in which follicular neoplasm has been diagnosed by FNAB awakes controversies. In practice it is impossible to determine reliably before surgery whether the lesion is malignant or not. Because of the rare incidence of thyroid cancer in the general population, more and more authors tend to decide on partial resection of the thyroid gland and possible radicalization if cancer is diagnosed on paraffin specimen examination.