A comparative study of two novel nanosized radiolabeled analogues of methionine for SPECT tumor imaging.

It has been reported that most tumor cells show an increased uptake of variety of amino acids specially methionine when compared with normal cells and amino acid transport is generally increased in malignant transformation. Based on the evidences, two novel nanosized analogues of methionine (Anionic Linear Globular Dendrimer G(2), a biodigredabale anionic linear globular-Methionin, and DTPA-Methionine(1) conjugates) were synthesized and labeled with (99m)Tc and used in tumor imaging/ therapy in vitro and in vivo. The results showed marked tumor SPECT molecular imaging liabilities for both compounds but with a better performance by administration of (99m)Tc-Dendrimer G(2)-Methionin. The results also showed a good anticancer activity for 99mTc-DTPA-Methionine. Based on the present study (99m)Tc-Dendrimer G(2)-Methionin or 99mTc-DTPA-(Methionine)(1) have potentials to be used in tumor molecular imaging as well as cancer therapy in future.

Tocilizumab for the treatment of large-vessel vasculitis (giant cell arteritis, Takayasu arteritis) and polymyalgia rheumatica.

OBJECTIVE: The interleukin-6 pathway is up-regulated in giant cell arteritis (GCA), Takayasu arteritis (TA), and polymyalgia rheumatica (PMR). We retrospectively assessed the outcomes of 10 patients with relapsing/refractory GCA, TA, or PMR treated with tocilizumab (TCZ). METHODS: Patients with GCA (n = 7), TA (n = 2), and PMR (n = 1) received TCZ. Seven subjects had failed at least 1 second-line agent. The outcomes evaluated were symptoms of disease activity, inflammatory markers, ability to taper glucocorticoids, and cross-sectional imaging when indicated clinically. RESULTS: The mean followup time of this cohort since diagnosis was 27 months (range 16-60 months). The patients were treated with TCZ for a mean period of 7.8 months (range 4-12 months). Before TCZ therapy, the patients experienced an average of 2.4 flares/year. All patients entered and maintained clinical remission during TCZ therapy. The mean daily prednisone dosages before and after TCZ initiation were 20.8 mg/day (range 7-34.3 mg/day) and 4.1 mg/day (range 0-10.7 mg/day), respectively (P = 0.0001). The mean erythrocyte sedimentation rate declined from 41.5 mm/hour (range 11-68 mm/hour) to 7 mm/hour (range 2.2-11.3 mm/hour; P = 0.0001). The adverse effects of TCZ included mild neutropenia (n = 4) and transaminitis (n = 4). One patient flared 2 months after TCZ discontinuation. An autopsy on 1 patient who died from a postoperative myocardial infarction following elective surgery revealed persistent vasculitis of large and medium-sized arteries. CONCLUSION: TCZ therapy led to clinical and serologic improvement in patients with refractory/relapsing GCA, TA, or PMR. The demonstration of persistent large-vessel vasculitis at autopsy of 1 patient who had shown a substantial response requires close scrutiny in larger studies.

Validity of venous blood gas analysis for diagnosis of acid-base imbalance in children admitted to pediatric intensive care unit.

BACKGROUND: Arterial blood gas (ABG) analysis is the major tool for proper diagnosis and treatment of acid-base imbalance, but the invasive nature of arterial puncture and its possible hazards such as arterial spasm have resulted in a worldwide trend toward less-invasive diagnostic methods including venous blood gas (VBG) analysis. This study aimed to evaluate the validity of VBG and its clinical agreement with ABG in the 10 most common diseases in pediatric intensive care unit (PICU), and to answer how far it can replace the ABG test. METHODS: In a cross-sectional analytical study from September 2004 to September 2005, 200 patients in 10 disease categories received blood gas analysis. Results of blood-gas tests such as pH, PCO2 and HCO3 of both arterial and venous blood samples (simultaneously taken from each patient) were recorded and compared by statistical analysis (kappa statistics) to determine their validity and clinical agreement. RESULTS: In some diseases such as respiratory distress syndrome, neonatal sepsis, renal failure, pneumonia, diabetic ketoacidosis and status epilepticus, VBG analysis showed a good validity (high sensitivity and specificity) accompanied by a suitable clinical agreement (over 40%), but in other diseases such as neonatal seizure, shock, congestive heart failure and congenital heart disease, there was either an inappropriately low validity or a weak clinical agreement (under 20%). CONCLUSIONS: VBG can be used instead of ABG in some diseases such as respiratory distress syndrome, neonatal sepsis, renal failure, pneumonia, diabetic ketoacidosis and status epilepticus, but in other diseases such as neonatal seizure, shock, congestive heart failure and congenital heart diseases, ABG is preferable and must not be replaced by VBG. These results may be used for the formulation of future guidelines for PICU.

Microstructure and rheological properties of Iranian white cheese coagulated at various temperatures.

The effect of milk coagulation temperature on the composition, microstructure monitored using scanning electron micrographs, opacity measured by a Hunter lab system, and rheological behavior measured by uniaxial compression and small amplitude oscillatory shear were studied. Three treatments of Iranian White cheese were made by applying coagulation temperatures of 34, 37, and 41.5 degrees C during the cheese-making procedure. A higher coagulation temperature resulted in increased fat and protein contents, and decreased the moisture content and ratio of moisture to protein. The highest temperature (41.5 degrees C) had a significant effect on the opacity of Iranian White cheese. Milk coagulation at this temperature decreased the whiteness index (Hunter L value) and increased the yellowness index (Hunter b value) of the aged product compared with cheeses coagulated at lower temperatures. Microstructure of the cheese coagulated at 41.5 degrees C was more compact and undisturbed, reflecting the higher values of stress at fracture and storage modulus measured for this treatment.

Rheology, microstructure, and functionality of low-fat Iranian white cheese made with different concentrations of rennet.

A batch of full-fat (23% target fat) and 3 batches of low-fat (6% target fat) Iranian white cheese with different rennet concentrations (1-, 2-, and 3-fold the normal usage) were produced to study the effect of fat content reduction and promoted proteolysis on the textural and functional properties of the product. Cheese samples were analyzed with respect to their rheological parameters (uniaxial compression and small amplitude oscillatory shear), meltability, microstructure, and sensory characteristics. Reduction of fat content from 23 to 6% had adverse effects on the texture, functionality, cheese-making yield, and sensory characteristics of Iranian white cheese. Fat reduction increased the instrumental hardness parameters (storage modulus, stress at fracture, and Young's modulus of elasticity), decreased the cheese meltability and yield, and made the microstructure more compact. Doubling the rennet concentration reduced values of instrumental hardness parameters, increased the meltability, and improved the sensory impression of texture. Although increasing the rennet concentration to 2-fold the normal usage resembled somewhat the low-fat cheese to its full-fat counterpart, it appeared to cause more reduction in yield. Increasing the rennet concentration 3-fold the normal usage produced a product slightly more elastic than the low-fat cheese with normal concentration of rennet. Increasing the rennet concentration to 2-fold the normal usage was useful for improving the textural, functional, and sensory properties of low-fat Iranian white cheese.