Creep behavior of human knee joint determined with high-speed biplanar video-radiography and finite element simulation.

Creep and relaxation of knee cartilage and meniscus have been extensively studied at the tissue level with constitutive laws well established. At the joint level, however, both experimental and model studies have been focused on either elastic or kinematic responses of the knee, where the time-dependent response is typically neglected for simplicity. The objectives of this study were to quantify the in-vivo creep behavior of human knee joints produced by the cartilaginous tissues and to use the relevant data to validate a previously proposed poromechanical model. Two participants with no history of leg injury volunteered for 3T magnetic resonance imaging (MRI) of their unloaded right knees and for biplanar video-radiography (BVR) of the same knees during standing on an instrumented treadmill for 10 min. Approximately 550 temporal data points were obtained for the in-vivo displacement of the right femur relative to the tibia of the knee. Models of the bones and soft tissues were derived from the MRI. The bone models were used to reconstruct the 3D bone kinematics measured using BVR. Ground reaction forces were simultaneously recorded for the right leg, which were used as input for the subject-specific finite element knee models. Cartilaginous tissues were modeled as fluid-saturated fibril-reinforced materials. In-vivo creep of the knee was experimentally observed for both participants, i.e., the joint displacement increased with time while the reaction forces at the foot were approximately constant. The creep displacements obtained from the finite element models compared well with the experimental data when the tissue properties were calibrated (Pearson correlation coefficient = 0.99). The results showed the capacity of the poromechanical knee model to capture the creep response of the joint. The combined experimental and model study may be used to understand the fluid-pressure load support and contact mechanics of the joint using material properties calibrated from the displacement data, which enhance the fidelity of model results.

The diagnostic value of immunohistochemistry in the typing of renal tumors with eosinophylic cytoplasma.

AIM: In this study, we aimed to review the diagnostic approach to eosinophilic cell renal neoplasms by light microscopy and immunohistochemical techniques. METHOD: In this study 23 of these tumors were eosinophilic variant classic RCC, 15 eosinophilic variant papillary RCC, 13 eosinophilic variant chromophobe RCC and 13 oncocytoma cases. These tumors were immunohistochemically treated with CK7, CD117, EpCAM, Vimentin, RCCm (Renal cell carcinoma marker) and GST-α. RESULTS: In our study, contrary to the general literature on Vimentin, 65.2 % negativity was found in our patients with eosinophilic variant classic RCC. However, when compared with other tumor types in our study, vimentin expression was highest in eosinophilic variant classical RCC with 34.8 %. Statistically; RCCm, GST-α, EpCAM, CD117, CK7 were found to be significantly associated with tumor types, while no significant relationship was found between Vimentin and tumor types. RCCm positivity and CK7 and CD117 negativity were in favour of eosinophilic variant classical RCC, EpCAM, CK7 and CD117 positivity and Vimentin, GST-α and RCCm negativity supported eosinophilic variant chromophobe RCC, CK7 and RCCm positivity and CD117 and GST-α negativity were found in favour of eosinophilic variant papillary RCC. CD117 positivity and Vimentin, CK7 and GST-α negativity were found to support oncocytoma. CONCLUSIONS: The panel with RCCm, GST-α, EpCAM, CD117, CK7 will contribute to the differentiation of eosinophilic cytoplasm renal tumors that cannot be determined by morphological findings and to reach the correct diagnosis (Tab. 3, Fig. 4, Ref. 54). Text in PDF www.elis.sk Keywords: RCC, oncocytoma, immunohistochemistry.

Airway changes in pregnant women before and after delivery.

AIM: High incidence of difficult or failed intubation in obstetric patients is still a major problem to challenge anaesthesiologists. Although the probability of difficult intubation is impossible to predict preoperatively, some simple, practical bedside tests may help. This study used five simple tests in an attempt to better evaluate airway changes in pregnant women before and after delivery. MATERIALS AND METHODS: Pregnant women from the ASA I-II group who were planning to undergo a normal vaginal delivery were evaluated as to the possibility of experiencing difficult intubation. Mallampati scores, thyromental distance, sternomental distance, mouth opening, and the degree of neck extension were recorded just before delivery and 24 h after delivery. RESULTS: Significant differences were seen in the pre- and post-delivery measurements (p < 0.05). Before delivery, Mallampati scores I, II, III, IV were 35, 24, 2, 0, respectively, and 24 h after delivery became 46, 15, 0, 0, respectively. CONCLUSIONS: Within 24 h after delivery, Mallampati scores changed in one-third (n 21, 36.6%) of the patients. Significant differences between the two measurements of thyromental and sternomental distances, mouth opening, and the degree of neck extension confirm difficult airway management in pregnant women.

Advanced glycation end products and antioxidant status in nondiabetic and streptozotocin induced diabetic rats: effects of copper treatment.

The effects of Cu(II) supplementation on glycemic parameters, advanced glycation end products (AGEs), antioxidant status (glutathione; GSH and total antioxidant capacity; TAOC) and lipid peroxidative damage (thiobarbituric acid-reactive substances, TBARS) were investigated in streptozotocin (STZ) induced diabetic rats. The study was carried out on Wistar albino rats grouped as control (n = 10), CuCl(2) treated (n = 9), STZ (n = 10) and STZ,CuCl(2) treated (n = 9). STZ was administered intraperitoneally at a single dose of 65 mg/kg and CuCl(2), 4 mg copper/kg, subcutaneously, every 2 days for 60 days. At the end of this period, glucose(mg/dl), Cu(microg/dl), TBARS(micromol/l), TAOC(mmol/l) were measured in plasma, GSH(mg/gHb) in erythrocytes and glycated hemoglobin (GHb)(%) in blood. Plasma AGE-peptides(%) were measured by HPLC flow system with spectrofluorimetric and spectrophotometric detectors connected on-line. Data were analyzed by the non-parametric Kruskal-Wallis and Mann-Whitney U test. In the STZ group glucose, GHb and AGE-peptide levels were all significantly higher than the control group (P < 0.01, P < 0.05, and P < 0.01, respectively). CuCl(2) treated group had significantly lower glucose but significantly higher GHb, TAOC and TBARS levels than the control group (P < 0.05, P < 0.001, P < 0.05 and P < 0.001, respectively). STZ,CuCl(2) treated group had significantly higher GHb, TAOC and TBARS levels compared with the control group (P < 0.001, P < 0.05 and P < 0.05, respectively); but only TAOC level was significantly higher than the STZ group (P < 0.01). This experimental study provides evidence that copper intake increases total antioxidant capacity in both nondiabetic and diabetic states. However despite the potentiated antioxidant defence, lipid peroxidation and glycation enhancing effects of CuCl(2) are evident under nondiabetic conditions.

Primary epiploic appendagitis: the role of computed tomography in diagnosis.

Primary epiploic appendagitis is a rare entity that occurs due to torsion and inflammation of the epiploic appendages. Clinically, this entity may be mistaken for acute abdomen with resultant unnecessary surgery. In contrast to acute surgical abdomen, epiploic appendagitis usually does not require surgical treatment; most of the patients resolve with conservative management. Diagnosis can be achieved with imaging modalities of which computed tomography is the gold standard procedure. Herein, a patient who presented with acute abdomen like clinical picture, with the computed tomography demonstration of primary epiploic appendagitis, is presented.

Effectiveness of tibolone on hypoestrogenic symptoms induced by goserelin treatment in patients with endometriosis.

OBJECTIVE: To investigate the efficacy and safety of tibolone on hypoestrogenic vasomotor symptoms and bone parameters in patients treated with goserelin acetate. DESIGN: Prospective, randomized placebo controlled double-blind study. SETTING: Human volunteers in a university-based fertility clinic. PATIENT(S): Twenty-nine women of mean age 29.2 +/- 4.8 years with mild to severe endometriosis undergoing 6 months of treatment with 3.6 mg goserelin acetate in an SC depot formulation were studied. INTERVENTION(S): The patients were allocated randomly to either 2.5 mg/d tibolone (n = 15) or an iron pill (n = 14) in a double-blinded fashion beginning in the third cycle. MAIN OUTCOME MEASURE(S): Frequency and severity of hot flushes, sweating, irritability, loss of libido, nervousness, and sleeplessness were assessed by the patients using 0 to 6 point scoring system and compared. Samples of urine were obtained for calcium and creatinine (Ca:Cr) ratios at the start of treatment and monthly there after. The vasomotor scoring for each symptom and Ca:Cr ratios before the treatment and at the end of 6th month were analyzed by parametric and nonparametric tests. RESULT(S): The mean age, weight, vasomotor scores, pelvic scores, and urine Ca:Cr ratios were similar in both placebo and tibolone group (28.7 +/- 4.8 versus 27.6 +/- 6.3 years, 50.9 +/- 5.3 versus 53.1 +/- 7.1 kg, 4.7 +/- 1.1 versus 4.2 +/- 0.8, and 0.056 +/- 0.008 versus 0.059 +/- 0.006, respectively). The decreases in vasomotor scoring as regards to hot flushing, sweating, and other associated symptoms were statistically significant in tibolone group compared with placebo (10.4 +/- 1.6 versus 24.6 +/- 4.9). During the study significant reductions in urine Ca:Cr ratio was obtained in the tibolone patients compared with placebo (0.031 +/- 0.006 versus 0.0055 +/- 0.007). The incidence of side effects (weight change, vaginal bleeding) was low and did not differ from the placebo group. CONCLUSION(S): Considering the beneficial effects of tibolone on vasomotor symptoms and bone loss, our data suggest that this synthetic steroid is an effective and safe option in relieving symptoms induced by GnRH-analogue.

The degree of fluid absorption during hysteroscopic surgery in patients pretreated with goserelin.

STUDY OBJECTIVE: To assess the effects of pretreatment with the gonadotropin-releasing hormone analog goserelin on fluid absorption in patients undergoing hysteroscopic endometrial ablation. DESIGN: Prospective, randomized, placebo-controlled study. SETTING: A university-based clinic. PATIENTS: Thirteen women with dysfunctional uterine bleeding who were scheduled for electrosurgical hysteroscopic ablation. INTERVENTIONS: Seven women were randomized to receive luteal phase goserelin 3.75 mg and six saline in the menstrual cycle approximately 10 weeks before surgery. Operative hysteroscopy was carried out with glycine 1.5% mixed with 2% alcohol medium under constant pressure as an irrigant. The amount of irrigant used, irrigant deficit, blood levels of albumin and ethanol, hematocrit, hemoglobin, changes in sodium levels, and central venous pressure were compared between the groups. MEASUREMENTS AND MAIN RESULTS: All of the patients had an unsuccessful course of medical therapy for at least 3 months and a normal endometrial biopsy. The age, weight, and uterine size were similar between the groups. The mean volume of irrigant used and operating time were similar in both groups (4.18 +/- 0.2 vs 4.5 +/- 0.5 L, and 33.7 +/- 1.5 vs 37 +/- 2.1 min). Although operating time, volume deficit, decrease in protein level, and hematocrit were less in the goserelin than in the saline group, the differences were not statistically significant (p >0.05). The ethanol levels in blood, decrease in Na+, and irrigant deficit were significantly lower in the goserelin than in the saline group (17.4 +/- 3.8 vs 25.3 +/- 4.2 mg/ml, 6.7 +/- 1.2 vs 9.1 +/- 0.9 mEq/L, and 0.49 +/- 0.08 vs 0.66 +/- 0.05 L, respectively; p <0.05). CONCLUSION: Based on these results we conclude that in women undergoing hysteroscopic endometrial ablation, pretreatment with goserelin may decrease the absorption of hysteroscopic medium, prevent fluid overload, and improve the outcome possibly by causing hypovascularity and decreased endometrial growth.