Short-Stranded Zein Fibers for Muscle Tissue Engineering in Alginate-Based Composite Hydrogels

Cultivated meat is a nascent technology that aims to create an environmentally and animal-friendly alternative to conventional meat. Producing skeletal muscle tissue in an animal-free system allowing for high levels of myofusion and maturation is important for the nutritional and sensorial value of cultivated meat. Alginate is an attractive biomaterial to support muscle formation as it is food-safe, sustainable and cheap and can be crosslinked using non-toxic methods. Although alginate can be functionalized to promote cell attachment, limitations in its mechanical properties, including form, viscosity, and stress relaxation, hinder the cellular capacity for myogenic differentiation and maturation in alginate-based hydrogels. Here, we show that the addition of electrospun short-stranded zein fibers increased hydrogel degradation, resulting in faster compaction, improved cell-gel interaction, and enhanced alignment of bovine muscle precursor cells. We conclude that fiber-hydrogel composites are a promising approach to support optimal formation of 3D constructs, by improving tissue stability and thus prolonging culture duration. Together, this improves muscle-related protein content by facilitating myogenic differentiation and priming muscle organoids for maturation.

Preoperative and postoperative ultrasound elastography findings of the sciatic nerve in patients with unilateral lumbar foraminal disc herniation: a pre-test and post-test design

OBJECTIVE

The aim of this study was to compare preoperative and postoperative findings of the sciatic nerve by using B-mode ultrasound, strain elastography (SE), and shear wave elastography (SWE) in patients with unilateral lumbar foraminal disc herniation.

PATIENTS AND METHODS

In this prospective study group, patients with complaints of foraminal disc herniation due to one level (L4-5 or L5-S1) were included. Preoperative and postoperative (one month after surgery) B-mode ultrasound, SE, and SWE findings of the affected sciatic nerve in patients who underwent unilateral spinal decompression surgery were compared. Evaluations were performed on the axial plane from the gluteal region using a convex probe of 5-9L MHz. The reference method used to assess nerve root compression was 1.5-T Magnetic Resonance Imaging (MRI).

RESULTS

A total of 20 patients (9 males, 11 females) with a mean age of 46.2±13.1 years were included. The cross-sectional area (CSA), diameter, SWE values of the sciatic nerve were significantly higher in the affected side compared to those of the non-affected side (all for p<0.05). Blue and blue-green were the most common color codes in the affected side while green and green-yellow-red were the most common color codes in the non-affected side. The CSA, diameter, and SWE values of the sciatic nerve decreased after the surgery in the affected side (all for p<0.05), nonetheless. those did not differ in the non-affected side (all for p>0.05).

CONCLUSIONS

Lumbar decompression surgery decreases the sciatic nerve diameter, CSA, and stiffness of the sciatic nerve.

Relative hypoaldosteronism in a patient with Wolcott-Rallison syndrome

BACKGROUND

Wolcott-Rallison syndrome is an autosomal recessive, multisystem disorder with onset of diabetes in the neonatal period or early infancy.

CASE REPORT

A 9-year-old girl with diabetes and growth failure from 2 months of age presented with ketoacidosis and multiple organ failure. Evaluation for short stature revealed epiphyseal dysplasia. A homozygous mutation in the EIF2AK3 gene confirmed the clinical diagnosis of Wolcott-Rallison syndrome. She was euthyroid. Biochemical evaluation for potential adrenal dysfunction because of persistently elevated serum potassium (range 5.9-6.3 meq/l) and low serum sodium levels (range 128-130 meq/l) 2 weeks after resolution of ketoacidosis yielded normal findings with respect to basal corticotropin (31 pg/ml) and cortisol (18.7 μg/dl) levels. Estimated GFR-Schwartz (36.9 ml/min/1.73 m(2) ) was consistent with stage 3 chronic renal failure. The transtubular potassium gradient was 1.39 (normal value in hyperkalemic states: > 4.1). The plasma aldosterone (upright: 241.3 pmol/l) was within normal ranges, and plasma renin [39 pg/ml (range 5.41-34.53 pg/ml)] was slightly elevated. The patient was diagnosed as having relative hypoaldosteronism and was started on a sodium-rich diet and low potassium. Failure to respond to the dietary intervention prompted a trial of oral fludrocortisone with subsequent normalization of electrolyte levels.

CONCLUSIONS

This is the first case report of Wolcott-Rallison syndrome complicated with relative hypoaldosteronism. Further research is needed to probe the causal inference of relative hypoaldosteronism with chronic renal failure in patients with Wolcott-Rallison syndrome.

Frailty prevalence and related factors in the older adult-FrailTURK Project

Frailty is one of the geriatric syndromes and has an important relationship with mortality and morbidity. The aim of this study is to present the characteristics, prevalence, and related factors of frailty in older adults in our country. The study included 1126 individuals over 65 years of age from 13 centers. Frailty was evaluated using the Fried Frailty criteria, and patients were grouped as "frail," "pre-frail," and "non-frail." Nutritional status was assessed with "Mini Nutritional Test," psychological status with the "Center for Epidemiological Studies Depression Scale-CES-D," and additional diseases with the "Charlson Comorbidity index." Approximately 66.5 % of the participants were between 65 and 74 years of age and 65.7 % were women. Some 39.2 and 43.3 % of the participants were rated as frail and pre-frail, respectively. The multinomial logistic regression analysis was used to determine the factors associated with frailty. It was observed that age, female gender, low education level, being a housewife, living with the family, being sedentary, presence of an additional disease, using 4 or more drugs/day, avoiding to go outside, at least one visit to any emergency department within the past year, hospitalization within the past year, non-functional ambulation, and malnutrition increased the risk of frailty (p < 0.05). Establishing the factors associated with frailty is highly important for both clinical practice and national economy. This is the first study on this subject in our country and will provide guidance in determining treatment strategies.

What do patients really know about cardiopulmonary rehabilitation: a cross-sectional survey study

BACKGROUND

Although it is known that cardiopulmonary rehabilitation (CPR) reduces mortality and morbidity, it is not widely implemented as is in Turkey. One factor might be lack of demand since the levels of knowledge and awareness among patients who are eligible for CPR seem to be insufficient.

AIM

It is aimed to investigate the level of awareness and knowledge of CPR among patients with cardiopulmonary problems.

DESIGN

Cross-sectional survey study.

SETTING

Outpatient.

METHODS

Knowledge regarding CPR was assessed by questionnaires given to 690 patients recruited in seven university hospitals and six training and research hospitals in which either comprehensive or limited CPR services are available.

POPULATION

Patients who have cardiopulmonary problems

RESULTS

Of the patients, 34.7% were given information on CPR by healthcare staff, and 25.3% reported that their source of information was physicians. Although 49.9% of the patients knew that they needed to exercise for their cardiac/pulmonary problems, only 23.4% and 32.1% of those were aware that fast walking and climbing stairs, respectively, would not pose a risk to their cardiac/pulmonary health. The majority of the patients believed that activities of daily living, which comprise the most important component of exercise-based CPR, were harmful for their cardiopulmonary health. We found that 31.1% of the patients exercised regularly. During their stay at the hospital, certain kinds of exercises were suggested to 62.7% of the patients, and 34.7% of these patients performed various exercises. Of the patients who were given detailed information on cardiopulmonary rehabilitation, 69% stated that they would be willing to participate in a similar program.

CONCLUSION

Although nearly half of the patients stated that they needed CR, it was observed that the ratio of patients who had true knowledge of CPR was low among patients. It is imperative to furnish patients with information on CPR, both in the field of PMR and throughout Turkey, and to put more effort into running those services effectively. Furthermore, we should make an effort to increase the level of liaison between patients and physicians and other healthcare professionals who participate in the treatment of cardiac/pulmonary patients.

A study of ionic composition and inorganic nutrient fluxes from rivers discharging into the Cilician Basin, Eastern Mediterranean

Present water quality of the perennial rivers; Göksu, Lamas, Efrenk, Tarsus and Seyhan discharging into the Cilician Basin have been investigated. Monthly surface samples collected from three stations downstream of the rivers during the period of October 2004-May 2005 were analyzed to determine ionic composition (Cl(-), SO(2-)(4), N(O-)(3), PO(3-)(4), N(H+)(4), Ca(2+), Mg(2+), Na(+) and K(+)), in addition to measurements of pH, electrical conductivity, alkalinity and total hardness. The results have been compared with recommended water quality standards. Excluding Göksu, Seyhan and Efrenk river mouths, values for almost all measured parameters, except N(H+)(4), were found to be lower than the desirable limits. In particular, inorganic ammonium, phosphate and nitrate concentrations for Göksu and Seyhan Deltas were 10(1) or 10(2) orders of magnitude higher than the concentrations of the rest of the samples. Temporal variation in levels, primarily observed in PO(3-)(4), suggest the impact of agricultural fertilizers intensively used around Göksu and Seyhan Rivers. According to Turkish National Water Pollution Control Regulations, all rivers were found to be unpolluted with respect to their nitrate, chloride, sulfate and sodium ion contents, while they all could be considered as slightly polluted with respect to their phosphate contents. In contrast to nitrate and phosphate, ammonium exceeded the maximum permissible limits of water quality criteria in almost all samples. Among the sampled rivers, Tarsus River was better in water quality, with the lowest electrical conductivity, alkalinity, total hardness and nutrient concentration values. Calculated values of elemental inorganic N and P fluxes suggest a substantial increase in nitrogen loads within the last decade, compared to a significant decrease in phosphorus loads of the rivers during the same period.

Vascular endothelial growth factor level in the serum of diabetic patients with retinopathy

We determined serum levels of vascular endothelial growth factor (VEGF) at different stages of diabetic retinopathy before laser photocoagulation in 65 patients (31 nonproliferative (Group 1) and 34 proliferative (Group 2)) and in healthy controls (Group 3). VEGF levels in all groups were different. There was a significant correlation between VEGF concentration and HbA1c levels. VEGF may be involved in the prediction of diabetic retinopathy and contributes to endothelial damage in diabetics.

Radial nerve injury after general anaesthesia in the lateral decubitus position

A 43-year-old female patient underwent pyelolithotomy in the left lateral decubitus position. Her upper right arm was placed on a padded armboard. Surgery lasted for 240 min. Postoperatively, she complained of numbness of the dorsal part of her right hand and wrist drop. Neurological examination revealed hypoaesthesia of the dermatome of the right forearm and hand innervated by the radial nerve. Electromyography revealed advanced axonal degeneration of the radial nerve below the level of the elbow. Treatment with diclofenac, vitamin B and physiotherapy was started. Her symptoms improved gradually and at the 60th postoperative day, motor weakness had completely resolved. In order to prevent peri-operative nerve injury, careful positioning of every patient on the operating table with proper padding is essential, with attention paid to time-dependent risks. If an injury occurs, diagnosis and treatment should be started as rapidly as possible.

Anatomical Characteristics of the Tibial Medullary Canal and Their Implications for Intramedullary Fixation

The use of intramedullary fixation methods in the tibia is limited by the anatomical characteristics of this bone. In this study, the shape and degree of axial lateral rotation of the medullary canal were determined in 45 human dry cadaver bones using X-ray and computed tomography examinations and direct measurement of rotation in inserted nails. Forty bones (88.8%) had slight and five bones (11.1%) had excessive anterior bowing along the tibial shaft. Six of the 45 bones (13.3%) had an extremely narrow medullary canal. Axial lateral rotation was demonstrated in the middle third of the medullary canal, being on average (± SD) 32.35 ± 16.25° (range 10-75°). This study revealed that extreme narrowing of the medullary canal, axial lateral rotation of the medullary canal, and extreme anterior bowing of the tibial shaft are the anatomical characteristics most likely to cause difficulties when using intermedullary fixation in the tibia.

The effects of folic acid application on IL-1beta levels of human gingival fibroblasts stimulated by phenytoin and TNFalpha in vitro: a preliminary study

Folic acid (FA), that is required for the integrity of gingival tissues, was found to decrease in patients using phenytoin (PHT). Interleukin-1 beta (IL-1beta) was reported to enhance the extracellular matrix synthesis in fibroblasts. The purpose of this study was to assess the role of FA supplementation on PHT-induced overgrowth by investigating its effect on IL-1beta production of human gingival fibroblasts induced by tumor necrosis factor alfa (TNFalpha) in cell culture. PHT (20 microg/ml), FA (20 or 40 ng/ml) + PHT, PHT + TNF (10 ng/ml), FA (20 or 40 ng/ml) + PHT + TNF, or only culture medium (control) was added to 24-well plates containing fibroblasts. After an incubation period of 72 h, culture medium and cells were harvested separately. Then, IL-1beta levels in cell lysate were measured using enzyme-linked immunosorbent assay. The cellular IL-1beta level in the PHT group was 1 pg/ml. In PHT + 20 or 40 ng/ml FA-added cultures, the results obtained respectively were 0.8 and 0.7 pg/ml, whereas the control group value was 0.7 pg/ml. IL-1beta level was 4 pg/ml in the cultures that PHT and TNFalpha were applied simultaneously (P < 0.05). When PHT and either 20 or 40 ng/ml FA were simultaneously added into TNFalpha-induced cultures, the IL-1beta levels were 1.8 and 1.3 pg/ml, respectively. IL-1beta level in gingival tissues might play a role in PHT-induced overgrowth by increasing in the gingival tissues, and FA application might play a role in decreasing gingival tissues. However, further studies are needed for a more complete understanding of PHT-induced gingival overgrowth at the cellular level.

The stability constants of copper(II) complexes with some alpha-amino acids in dioxan-water mixtures

In this study, the overall stability constants of copper(II) complexes with some alpha-amino acids (glycine, dl-alanine, dl-valine, l-leucine, l-asparagine, l-glutamine) were determined by potentiometric titration in water, 25% dioxan-75% water, 35% dioxan-65% water, 50% dioxan-50% water, and 60% dioxan-40% water. The titrations were performed at 25 degrees C, under nitrogen atmosphere, and the ionic strength of the medium was maintained at 0.10 M by using sodium perchlorate. The formation curves of their complexes (n-p[L]) were obtained by means of the titration data. Then the stability constants were determined in relation to these curves. The mol ratio of copper(II) to alpha-amino acid was also determined and it was found that the complexes were CuL(2) type. Another important result obtained was that the tendency of amino acids to form complexes with copper(II) was greater in dioxan-water mixtures compared to water.

Attenuation of brain edema, blood-brain barrier breakdown, and injury volume by ifenprodil, a polyamine-site N-methyl-D-aspartate receptor antagonist, after experimental traumatic brain injury in rats

OBJECTIVE

Traumatic brain injury (TBI) has been shown to induce a significant change in polyamine metabolism. Polyamines and polyamine-dependent calcium influx play an important role in mediating the effects of excitotoxic amino acids at the N-methyl-D-aspartate (NMDA) receptor site. We studied the effects of ifenprodil, known as a noncompetitive inhibitor of polyamine sites at the NMDA receptor, on brain edema formation, blood-brain barrier breakdown, and volume of injury after TBI.

METHODS

Experimental TBI was induced in Sprague-Dawley rats by a controlled cortical impact device, functioning at a velocity of 3 m/s to produce a 2-mm deformation. Ifenprodil or saline (10 mg/kg) was injected intraperitoneally immediately after the cortical impact injury and then every 90 minutes until 6 hours after TBI. Blood-brain barrier breakdown was evaluated quantitatively 6 hours after injury by fluorometric assay of Evans blue extravasation. Brain water content, an indicator of brain edema, was measured with the wet-dry method 24 hours after TBI. Injury volume was quantitated from the brain slices stained with 2% cresyl violet solution 7 days after TBI.

RESULTS

Blood-brain barrier breakdown was significantly lower in the traumatic cortex of the ifenprodil-treated group than in the saline-treated group (84.4 +/- 26.8 microg/g versus 161.8 +/- 27 microg/g, respectively, P < 0.05). Brain edema was significantly reduced in the cortex of the ifenprodil-treated group relative to that in the saline-treated group (80.9 +/- 0.5% versus 82.4 +/- 0.6% respectively, P < 0.05). Ifenprodil treatment reduced injury volume significantly (14.9 +/- 8.1 mm3 versus 24.4 +/- 6.7 mm3, P < 0.05).

CONCLUSION

The polyamine-site NMDA receptor antagonist ifenprodil affords significant neuroprotection in a controlled cortical impact brain injury model and may hold promise for the discovery and treatment of the mechanism of delayed neurological deficits after TBI.

Elevated N1-acetylspermidine levels in gerbil and rat brains after CNS injury

The polyamine system is very sensitive to different pathological states of the brain and is perturbed after CNS injury. The main modifications are significant increases in ornithine decarboxylase activity and an increase in tissue putrescine levels. Previously we have shown that the specific polyamine oxidase (PAO) inhibitor N1,N4-bis(2,3-butadienyl)-1,4-butanediamine (MDL 72527) reduced the tissue putrescine levels, edema, and infarct volume after transient focal cerebral ischemia in spontaneously hypertensive rats and traumatic brain injury of Sprague-Dawley rats. In the present study, N1-acetyl-spermidine accumulation was greater in injured brain regions compared with sham or contralateral regions following inhibition of PAO by MDL 72527. This indicates spermidine/spermine-N1-acetyltransferase (SSAT) activation after CNS injury. The observed increase in N1-acetylspermidine levels at 1 day after CNS trauma paralleled the decrease in putrescine levels after treatment with MDL 72527. This suggests that the increased putrescine formation at 1 day after CNS injury is mediated by the SSAT/PAO pathway, consistent with increased SSAT mRNA after transient ischemia.

Neuroprotective effects of citicoline on brain edema and blood-brain barrier breakdown after traumatic brain injury

OBJECT

Cytidine 5'-diphosphocholine (CDPC), or citicoline, is a naturally occurring endogenous compound that has been reported to provide neuroprotective effects after experimental cerebral ischemia. However, in no study has such protection been shown after traumatic brain injury (TBI). In this study the authors examined the effect of CDPC on secondary injury factors, brain edema and blood-brain barrier (BBB) breakdown, after TBI.

METHODS

After anesthesia had been induced in Sprague-Dawley rats by using 1.5% halothane, an experimental TBI was created using a controlled cortical impact (CCI) device with a velocity of 3 m/second, resulting in a 2-mm deformation. Four sham-operated control animals used for brain edema and BBB breakdown studies underwent the same surgical procedure, but received no injury. Brain edema was evaluated using the wet-dry method 24 hours postinjury, and BBB breakdown was evaluated by measuring Evans blue dye (EBD) extravasation with fluorescein 6 hours after TBI. The animals received intraperitoneal injections of CDPC (50, 100, or 400 mg/kg two times after TBI [eight-10 animals in each group]) or saline (eight animals) after TBI. Traumatic brain injury induced an increase in the percentage of water content and in EBD extravasation in the injured cortex and the ipsilateral hippocampus. No significant benefit from CDPC treatment was observed at a dose of 50 mg/kg. Cytidine 5'-diphosphocholine at a dose of 100 mg/kg attenuated EBD extravasation in both regions, although it reduced brain edema only in the injured cortex. In both regions, 400 mg/ kg of CDPC significantly decreased brain edema and BBB breakdown.

CONCLUSIONS

This is the first report in which dose-dependent neuroprotective effects of CDPC have been demonstrated in the injured cortex as well as in the hippocampus, a brain region known to be vulnerable to injury, after experimental TBI. The results of this study suggest that CDPC is an effective neuroprotective agent on secondary injuries that appear following TBI.

Interaction between AVP and sympathetic system in subtotal nephrectomy-saline hypertension: role of alpha and V1 receptors

The development process of subtotal nephrectomy-salt hypertension is still unclear. The aim of the present study was to determine the role of the interaction between vasopressin and sympathetic system in the development of this hypertension by using AVP V1 antagonist and alpha blocker phentolamine under anesthesia condition. For this purpose, we carried out about 73% subtotal nephrectomy on male Wistar rats. One group of these rats (normotensive group) was given a low-salt diet and the other group (hypertensive group) was given a high-salt diet for 4 weeks. Finally, eight groups of rats were formed according to the kind(s) of the injected drug(s): (1) normotensive and hypertensive groups injected only V1 antagonist, (2) normotensive and hypertensive groups injected only phentolamine, (3) normotensive and hypertensive groups injected first V1 antagonist and then phentolamine, (4) normotensive and hypertensive groups injected first phentolamine and then V1 antagonist. Either V1 or alpha blockage separately led to a higher reduction in the mean blood pressure (MAP) of the hypertensives than, of the normotensives (p < 0.05). The combined blockage of V1 and alpha receptors, also caused a higher decrease in the MAP of hypertensive group than, of normotensive group, not depending on the order of the injections (p < 0.01). The heart rate increase recorded as a response to the phentolamine injection in normotensive group, did not develop in hypertensive group (p < 0.05). There was no significant difference between the two groups with regard to plasma electrolytes and osmolality. A positive correlation was found between systolic blood pressure and plasma osmolality in hypertensive group (r = 0.40, p < 0.05), but not in normotensive group. We conclude that the increase in V1 and alpha pressor activities contributes to the subtotal nephrectomy-saline hypertension and the augmentation of alpha pressor activity by vasopressin may participate in this contribution.

Application of 2,3,5-triphenyltetrazolium chloride staining to evaluate injury volume after controlled cortical impact brain injury: role of brain edema in evolution of injury volume

A reliable method for measuring injury volume after traumatic brain injury (TBI) is of great importance when studying pharmacological protective agents in the field of head trauma research. Utilization of 2,3,5-triphenyltetrazolium chloride (TTC) has gained extensive acceptance in stroke research and has recently been applied to injury volume measurement in the lateral fluid percussion model. The present study was undertaken to apply this method to the controlled cortical impact (CCI) model and to study the role of brain edema. Male Sprague-Dawley rats were subjected to CCI brain injury at a velocity of 3 m/sec and 1 mm (mild), 2 mm (moderate), and 3 mm (severe injury) deformation, while rats in the control group were subjected to the same surgical procedure but received no injury. Absolute and corrected injury volumes with TTC staining and brain edema measurements with the wet-dry method were evaluated at 1, 2, 3, 4, and 7 days after TBI. The most prominent injury volume in the moderate injury group (2 mm deformation) was seen at postinjury day 1 and 2 (day 1, absolute: 49.1+/-5.6, corrected: 40.5+/-7.9; day 2, absolute: 46+/-6.9, corrected: 40.2+/-10.5), whereas the smallest injury volume was found at postinjury day 7 (absolute: 24.9+/-7, corrected: 27.4+/-7.4). The time course of brain edema studies demonstrates that brain edema formation peaks at postinjury day 1. A statistically significant reduction of injury volume was observed after postinjury day 4. We also observed that due to the presence of brain edema absolute injury volume is more than corrected injury volume in the first 3 days after injury as opposed to injury volume at postinjury day 7. These results suggest that the measurement of injury volume with TTC staining should be corrected for brain edema in the CCI brain injury model.

Application of endovascular suture occlusion of middle cerebral artery in gerbils to obtain consistent infarction

Middle cerebral artery occlusion (MCAO) by endovascular suture has gained increasing acceptance because it is relatively non-invasive and allows reperfusion. However, its application in rats has resulted in inconsistent infarction volumes which involve only the subcortex or subcortex plus some cortex. In order to eliminate this drawback, we applied the intraluminal suture occlusion of MCA to gerbils that have an incomplete Circle of Willis. MCAO was induced by inserting an endovascular 5-0 nylon suture with a blunted tip into the Circle of Willis. Animals were divided into two groups: permanent MCAO for 24 h (n = 8) and transient MCAO for 3 h with 21 h reperfusion (n = 8). The corrected infarction volume in the permanent MCAO group was 232 +/- 37 mm3 whereas it was 230 +/- 45 mm3 in the transient MCAO group. All animals in both groups had infarction in both cortex and subcortex. Results of this study show that endovascular suture occlusion of MCA can be easily applied in gerbils to obtain consistent infarction. This would allow both transient and permanent focal ischemia to be tested in the same model of ischemia.

Activity of factor VIIa and von Willebrand factor in non-insulin-dependent diabetic subjects with coronary artery disease

Atherosclerosis is more extensive and occurs earlier in diabetics compared with the general population. The pathophysiology of atherosclerosis is not fully established. We compared the activity of two blood clotting agents, activated factor VII (VIIa) and von Willebrand factor (vWF), in diabetic and non-diabetic subjects with coronary artery disease. According to clinical features, subjects were placed in one of four groups: Group I, non-insulin-dependent diabetes mellitus (NIDDM) with coronary heart disease (CAD) (n = 16); Group II, NIDDM (n = 15); Group III, CAD with no presence of diabetes (n = 17); and Group IV, healthy volunteers (n = 15). The level of factor VIIa was higher in Group I compared with all other groups, and was significantly higher in Group II compared with Group III and Group IV. Activity of vWF was higher in Group I compared with Group II, Group III and Group IV. There was no statistical difference between Group II and Group III. There was no significant correlation between concentration of blood glucose, total cholesterol or triglyceride, duration of diabetes and either factor VIIa or vWF activity. The results of this study suggest that increased activity of plasma vWF and factor VIIa may be useful markers to identify ischaemic heart disease risk in NIDDM subjects.

Contribution of polyamine oxidase to brain injury after trauma

OBJECT

The possible role of the polyamine interconversion pathway on edema formation, traumatic injury volume, and tissue polyamine levels after traumatic brain injury (TBI) was studied using an inhibitor of the interconversion pathway enzyme, polyamine oxidase.

METHODS

Experimental TBI was induced in Sprague-Dawley rats by using a controlled cortical impact device at a velocity of 3 m/second, resulting in a 2-mm deformation. Immediately after TBI was induced, 100 mg/kg of N1,N4-bis(2,3-butadienyl)-1,4-butanediamine 2HCl (MDL 72527) or saline was injected intraperitoneally. Brain water content and tissue polyamine levels were measured at 24 hours after TBI. Traumatic injury volume was evaluated using 2% cresyl violet solution 7 days after TBI occurred. The MDL 72527 treatment significantly reduced brain edema (80.4+/-0.8% compared with 81.2+/-1.2%, p < 0.05) and injury volume (30.1+/-6.6 mm3 compared with 42.7+/-13.3 mm3, p < 0.05) compared with the saline treatment. The TBI caused a significant increase in tissue putrescine levels at the traumatized site (65.5+/-26.5 nmol/g [corrected] in the cortex and 70.9+/-22.4 nmol/g [corrected] in the hippocampus) compared with the nontraumatized site (7+/-2.4 nmol/g [corrected] in the cortex and 11.4+/-6.4 nmol/g [corrected] in the hippocampus). The increase in putrescine levels in both the traumatized and nontraumatized cortex and hippocampus was reduced by a mean of 60% with MDL 72527 treatment.

CONCLUSIONS

These results demonstrate, for the first time, that the polyamine interconversion pathway has an important role in the increase of putrescine levels after TBI and that the polyamine oxidase inhibitors, blockers of the interconversion pathway, can be neuroprotective against edema formation and necrotic cavitation after TBI.

A study on impact and tensile strength of acrylic resin filled with short ultra-high molecular weight polyethylene fibers

In dentistry, acrylates have been used for preparing denture bases for 50 years. Although polymethylmethacrylates (PMMA) are known to be an ideal base material, they possess some undesirable mechanical properties, especially their impact strength and tensile strength, which appear to be unsatisfactory for some applications. Additives and fibers have therefore been used to enhance and improve these properties over the last two decades. The present article describes the mechanical properties, impact and tensile strength of PMMA reinforced with chopped ultra-high molecular weight polyethylene fiber (6 mm long). It was found that, although the processing involved for high loading of fibers into the PMMA was difficult, the resulting improvement of impact strength was substantial.

Effects of MDL 72527, a specific inhibitor of polyamine oxidase, on brain edema, ischemic injury volume, and tissue polyamine levels in rats after temporary middle cerebral artery occlusion

The possible effects of the polyamine interconversion pathway on tissue polyamine levels, brain edema formation, and ischemic injury volume were studied by using a selective irreversible inhibitor, MDL 72527, of the interconversion pathway enzyme, polyamine oxidase. In an intraluminal suture occlusion model of middle cerebral artery in spontaneously hypertensive rats, 100 mg/kg MDL 72527 changed the brain edema formation from 85.7 +/- 0.3 to 84.5 +/- 0.9% in cortex (p < 0.05) and from 79.9 +/- 1.7 to 78.4 +/- 2.0% in subcortex (difference not significant). Ischemic injury volume was reduced by 22% in the cortex (p < 0.05) and 17% in the subcortex (p < 0.05) after inhibition of polyamine oxidase by MDL 72527. There was an increase in tissue putrescine levels together with a decrease in spermine and spermidine levels at the ischemic site compared with the nonischemic site after ischemia-reperfusion injury. The increase in putrescine levels at the ischemic cortical and subcortical region was reduced by a mean of 45% with MDL 72527 treatment. These results suggest that the polyamine interconversion pathway has an important role in the postischemic increase in putrescine levels and that blocking of this pathway can be neuroprotective against neuronal cell damage after temporary focal cerebral ischemia.

Traumatic brain injury down-regulates glial glutamate transporter (GLT-1 and GLAST) proteins in rat brain

Excess activation of NMDA receptors is felt to participate in secondary neuronal damage after traumatic brain injury (TBI). Increased extracellular glutamate is active in this process and may result from either increased release or decreased reuptake. The two high-affinity sodium-dependent glial transporters [glutamate transporter 1 (GLT-1) and glutamate aspartate transporter (GLAST)] mediate the bulk of glutamate transport. We studied the protein levels of GLT-1 and GLAST in the brains of rats after controlled cortical impact-induced TBI. With use of subtype-specific antibodies, GLT-1 and GLAST proteins were quantitated by immunoblotting in the ipsilateral and contralateral cortex at 2, 6, 24, 72, and 168 h after the injury. Sham-operated rats served as control. TBI resulted in a significant decrease in GLT-1 (by 20-45%; p < 0.05) and GLAST (by 30-50%; p < 0.05) protein levels between 6 and 72 h after the injury. D-[3H]Aspartate binding also decreased significantly (by 30-50%; p < 0.05) between 6 and 72 h after the injury. Decreased glial glutamate transporter function may contribute to the increased extracellular glutamate that may mediate the excitotoxic neuronal damage after TBI. This is a first report showing altered levels of glutamate transporter proteins after TBI.

Effects of ifenprodil, a polyamine site NMDA receptor antagonist, on reperfusion injury after transient focal cerebral ischemia

Polyamines and N-methyl-D-aspartate (NMDA) receptors are both thought to play an important role in secondary neuronal injury after cerebral ischemia. Ifenprodil, known as a noncompetitive inhibitor of polyamine sites at the NMDA receptor, was studied after transient focal cerebral ischemia occurred. Spontaneously hypertensive male rats, each weighing between 250 and 350 g, underwent 3 hours of tandem middle cerebral artery (MCA) and common carotid artery occlusion followed by reperfusion for a period of 3 hours or 21 hours. Intravenous ifenprodil (10 microg/kg/minute) or saline infusion was started immediately after the onset of MCA occlusion and continued throughout the ischemic period. Physiological parameters including blood pressure, blood gas levels, blood glucose, hemoglobin, and rectal and temporal muscle temperatures were monitored. Six rats from each group were evaluated at 6 hours postocclusion for brain water content, an indicator of brain edema, and Evans blue dye extravasation for blood-brain barrier breakdown. Infarct volume was also measured in six rats from each group at 6 and 24 hours postocclusion. Ifenprodil treatment significantly reduced brain edema (82.5 +/- 0.4% vs. 83.5 +/- 0.4%, p < 0.05) and infarct volume (132 +/- 14 mm3 vs. 168 +/- 25 mm3, p < 0.05) compared with saline treatment, with no alterations in temporal muscle (brain) or rectal (body) temperature (35.9 +/- 0.4 degrees C vs. 36.2 +/- 0.2 degrees C; 37.7 +/- 0.4 degrees C vs. 37.6 +/- 0.6 degrees C; not significant). These results demonstrate that ifenprodil has neuroprotective properties after ischemia/reperfusion injury in the absence of hypothermia. This indicates that antagonists selective for the polyamine site of the NMDA receptors may be a viable treatment option and helps to explain some of the pathophysiological mechanisms involved in secondary injury after transient focal cerebral ischemia has occurred.

The biphasic opening of the blood-brain barrier in the cortex and hippocampus after traumatic brain injury in rats

This study examined the time course of the blood-brain barrier (BBB) opening and correlated this with brain edema formation after a lateral controlled cortical impact (CCI) brain injury in rats. Quantitative measurement of Evans blue (EB) extravasation using fluorescence was employed at 2, 4, 6 h and 1, 2, 3, 4 and 7 days after injury. Brain edema was measured by specific gravity of the tissue at corresponding time points. Two prominent EB extravasations were observed at 4-6 h and 3-day after injury in the injury-site cortex and the ipsilateral hippocampus. Brain edema became progressively more severe over time and peaked at 24 h after injury and began to decline after day 3. These results suggest that there is a biphasic opening of the BBB after CCI brain injury and the second opening of the BBB does not contribute to a further increase in edema formation.

The first case of periureteric hibernoma. Case report

Hibernoma is a rare type of soft tissue neoplasm originating from brown fat tissue. The present case is the first periureteric hibernoma concentrically surrounding the ureter with a concomitant renal pelvis stone.

Primary extramedullary plasmacytoma of the liver

Extramedullary plasmacytoma of the liver is a rare tumour, only two cases of which have been reported so far. A third case arising in a 22 year old woman, who presented with abdominal pain and enlargement of the liver, is described. Ultrasound and a computed tomography scan showed a solitary hepatic mass, 12 cm diameter, involving both lobes of the liver. Serum immunoelectrophoresis revealed an IgG kappa monoclonal gammopathy. Histologically, the tumour was composed of mature plasma cells with mild atypia. The plasma cells infiltrated the liver parenchyma and showed kappa light chain restriction. The monoclonal nature of the tumour was also demonstrated by PCR amplification of the immunoglobulin heavy chain genes. There was no evidence of bone involvement and repeated bone marrow aspirates and biopsy specimens were normal. The patient was treated with eight courses of chemotherapy. One year after diagnosis, the patient is well, the size of the tumour has decreased and the paraproteinaemia has disappeared.

The effect of preparation conditions of acrylic denture base materials on the level of residual monomer, mechanical properties and water absorption

OBJECTIVES AND METHODS

The curing of several commercial powder/liquid mixtures of acrylic denture base materials was carried out at different temperatures and curing times. The levels of residual monomer, tensile strength, percentage elongation before break and water absorption were measured.

RESULTS AND CONCLUSION

It was found that the level of residual monomer determined by gas-liquid chromatography decreased with curing time and temperature increase. At the same time, the tensile strength was improved and water absorption decreased.

E-cadherin expression in intestinal epithelium

AIMS

To investigate E-cadherin expression in normal and inflamed intestine, in the colonic adenocarcinoma cell line HT29, in normal fetal intestine, and in a fetal gut organ culture model where a T cell mediated enteropathy can be generated; to determine whether expression of E-cadherin changes in intestinal inflammation.

METHODS

Immunohistochemistry was used to determine E-cadherin expression in following tissues: frozen and paraffin wax sections of normal and inflamed intestine; HT29 colonic adenocarcinoma cell line cultured on coverslips in the presence or absence of cytokines; frozen sections of fetal small intestinal tissue (gestational age 11-22 weeks); and frozen sections of cultured fetal gut in which a T cell mediated enteropathy had been induced.

RESULTS

E-cadherin was strongly and evenly expressed by the epithelium in all specimens of intestine studied. Although there was no change in inflammation generally, in some cases of Crohn's disease groups of glands with the characteristic morphology of "ulcer associated cell lineage" showed lower expression of E-cadherin. In fetal gut organ cultures epithelial expression of E-cadherin was lower when local T cells were activated with mitogens, compared with control explants. By contrast, the HT29 cell line showed low levels of expression which increased after treatment with conditioned medium from activated tonsil cells.

CONCLUSIONS

E-cadherin is strongly and evenly expressed by epithelium in normal and inflamed intestine, although an increase in E-cadherin expression in cytokine treated HT29 cells was observed. E-cadherin expression is reduced in the epithelium adjacent to ulcers (ulcer associated cell lineage), possibly to assist regeneration.

Endogenous digoxin-immunoreactive substance in normal and preeclamptic pregnancies

AIMS

To determine the potential use of a digoxin-immunoreactive substance in the prediction of preeclampsia, to study the relationship between serum levels of this substance and gestational age, and to evaluate the correlation between this substance and blood pressure findings in preeclamptic pregnancies.

METHODS

Serum digoxin-immunoreactive substance concentrations were measured by RIA (double antibody radioimmunoassay) in normotensive (n = 14) and preeclamptic (n = 17) pregnant women in their third trimesters. Statistical evaluation was performed with the Mann-Whitney U-test and correlation-regression analysis.

RESULTS

The mean (+/- S.E.) digoxin-immunoreactive substance levels in the normal and preeclamptic patients were 0.29 +/- 0.06 and 0.31 +/- 0.05 ng/ml, respectively, the slightly higher level in the hypertensive group being statistically non-significant. Serum digoxin-immunoreactive substance levels did not demonstrate good correlation with gestational age and systolic blood pressure in preeclamptic pregnancies.

CONCLUSIONS

An endogenous digoxin-immunoreactive substance is present in the sera of third trimester pregnant women, but it does not contribute to the pathogenesis or prediction of preeclampsia.

Cyclosporin A enhances T cell-mediated induction of E-selectin

In a fetal intestinal organ culture model of intestinal inflammation, activation of T cells by a lectin, superantigen or anti-CD3 antibodies induces E-selectin expression which peaks 6-10 h after activation and disappears by 24 h. We now show that addition of cyclosporin A (Cys A) increases the number of E-selectin-expressing endothelial cells and the intensity of expression, and it prolongs expression up to at least 60 h after stimulation. The dynamics of E-selectin expression on tumor necrosis factor activated human umbilical vein endothelial cell cultures is not affected by Cys A. Furthermore, other immunosuppressive agents FK506 and dexamethasone inhibit E-selectin expression, indicating that the enhancement observed in the presence of Cys A is not a consequence of general immunosuppression.

Pulmonary function parameters, arterial blood gases and flow volume curves of dental technicians

Dental technicians working in laboratories are exposed to different doses of various dusts. Disorders of pulmonary function may occur before radiographic changes are evident. If these pulmonary function disorders are found at an early stage, the risk may be reduced by early, adequate local ventilation and by appropriate individual protective methods. Unless adequate preventive measures are taken, pulmonary disorders will increase, finally leading to obstructive or restrictive ventilatory disorders, or progressive massive fibrosis. Results of pulmonary function tests provide objective criteria for prognosis, and are a measure of disease disability. In this situation, abnormal pulmonary function results should be considered as alarm signs.

Ontogeny and induction of adhesion molecule expression in human fetal intestine

In this study we examined the distribution of the adhesion molecules ICAM-1, VCAM-1 and E-selectin in human fetal intestine, to determine whether they may have a role in the development of gut-associated lymphoid tissue. Secondly, we studied the tempo of induction of these molecules after T cell activation in explants of human fetal intestine cultured in vitro. In the fetus from 11 to 20 weeks gestation, endothelial expression of ICAM-1 and diffuse staining of VCAM-1 was observed in the lamina propria. In contrast, there was intense expression of ICAM-1 and VCAM-1 in the developing Peyer's patches, suggesting that these molecules may be involved in the accumulation or organization of lymphoid tissue in the gut. After T cell activation in fetal intestinal explants, the expression of ICAM-1 and VCAM-1 was increased on most endothelial cells, leucocytes, and stromal cells in the lamina propria. Expression was maintained for at least 4 days. In contrast, the induction of E-selectin was rapid, and the expression was transient, despite the continuing presence of activated T cells and macrophages. This suggests that other factors are required to prevent the down-regulation of E-selectin to maintain the sustained expression sometimes observed in vivo.

Inhibitory and stimulatory effects of cumin, oregano and their essential oils on growth and acid production of Lactobacillus plantarum and Leuconostoc mesenteroides

Cumin at concentrations of 0.5, 1.0 and 2.0% (w/w) stimulated growth and acid production of Lactobacillus plantarum and Leuconostoc mesenteroides in a liquid medium. Essential oil from cumin at high concentrations (300 and 600 ppm) inhibited growth and acid production of Lactobacillus plantarum. After a certain period, growth of Leuconostoc mesenteroides was observed at all concentrations (150, 300 and 600 ppm) and its acid production was stimulated at 600 ppm. Oregano and its essential oil at all concentrations inhibited growth of both cultures. Acid production by Lactobacillus plantarum was stimulated by oregano spice.

Familial short rib syndrome, type Beemer, with pyloric stenosis and short intestine, one case diagnosed prenatally

Two sibs with Beemer type short rib syndrome, one of them diagnosed in utero, are reported. Both patients had previously unreported additional abnormalities such as pyloric stenosis and short bowels. Dysplasia of pancreatic Langerhans cells was present in one sib.

Primary subconjunctival lymphoma: an unusual presentation of childhood non-Hodgkin's lymphoma

Of 806 non-Hodgkin's lymphoma cases, only one primary subconjunctival lymphoma case was observed in Hacettepe Children's Hospital over a period of 16 years. The patient was a 12 year-old-boy with a subconjunctival mass on the upper part of his right eye. Biopsy revealed malignant lymphoma. Extensive investigations disclosed no other site of tumor. He was given the modified LSA2-L2 protocol. He has been in remission for 22 months. This may be the first report of a primary subconjunctival lymphoma in the childhood period.