Experimental energy resolution of a paracentric hemispherical deflector analyzer for different entry positions and bias

A specially designed hemispherical deflector analyzer (HDA) with 5-element input lens having a movable entry position R0 suitable for electron energy analysis in atomic collisions was constructed and tested. The energy resolution of the HDA was experimentally determined for three different entry positions R0 = 84, 100, 112 mm as a function of the nominal entry potential V(R0) under pre-retardation conditions. The resolution for the (conventional) entry at the mean radius R0 = 100 mm was found to be a factor of 1.6-2 times worse than the resolution for the two (paracentric) positions R0 = 84 and 112 mm at particular values of V(R0). These results provide the first experimental verification and a proof of principle of the utility of such a paracentric HDA, while demonstrating its advantages over the conventional HDA: greater dispersion with reduced angular aberrations resulting in better energy resolution without the use of any additional fringing field correction electrodes. Supporting simulations of the entire lens plus HDA spectrometer are also provided and mostly found to be within 20%-30% of experimental values. The paracentric HDA is expected to provide a lower cost and∕or more compact alternative to the conventional HDA particularly useful in modern applications utilizing a position sensitive detector.

A study on the effects of pica and iron-deficiency anemia on oxidative stress, antioxidant capacity and trace elements

Pica is defined as developmentally inappropriate consumption of nonnutritive substances for at least 1 month. There are a few studies on serum trace element levels of patients with pica. The literature contains contracting data on the levels of oxidative stress and antioxidant levels in patients with iron-deficiency anemia (IDA). The effect of pica on oxidative stress and antioxidant capacity has not been investigated yet. The present study evaluated the effects of pica and IDA on oxidative stress and antioxidant capacity as well as on the levels of trace elements including serum zinc and selenium in 47 children with IDA plus pica, 22 children with IDA only and 21 nonanemic children as controls. The results demonstrated significantly lower levels of serum selenium and zinc in pica and IDA groups compared to the control group. Total oxidant levels were highest in the pica group and consistently, the lowest total antioxidant capacity was observed again in the pica group. Comparison of pica and IDA groups yielded significantly lower levels of total antioxidant levels and significantly higher oxidative stress index in the pica group. Consequently, it is thought that the detrimental effects of pica within the organism were mediated by adverse impacts on antioxidant capacity and oxidative stress. These effects should be kept in mind while managing patients with pica.

Relationship between antimetabolite toxicity and pharmacogenetics in Turkish cancer patients

INTRODUCTION

Antimetabolites may cause severe toxicity and even toxic death in cancer patients. Our aim was to evaluate the relationship between antimetabolite toxicity and pharmacogenetics in patients with severe clinical toxicity or alanine transaminase (ALT) elevation after fluorouracil (5FU), capecitabine or methotrexate administration.

PATIENTS AND METHODS

Cancer patients with severe antimetabolite toxicity were evaluated for methylenetetrahydrofolate reductase (MTHFR) gene C667T, thymidilate synthase (TS) gene 5' UTR variable number of tandem repeats (VNTR), dihydroprymidine dehydrogenase (DPYD) gene IVS14+1G/A, Xeroderma pigmentosum (XPD) gene Lys751Gln and X-ray repair cross-complementing group 1 (XRCC1) gene Arg399Gln polymorphisms.

RESULTS

Eighteen patients were enrolled, with a male/female ratio of 0.8. They had osteosarcoma in methotrexate group (n=7), gastrointestinal malignancies in 5FU group (n=9) and breast cancer in the capecitabine group (n=2). Mucositis and dermatitis occurred in all groups, together with ALT elevation in the methotrexate group and 2 toxic deaths were encountered. DPYD, TS, MTHFR, XPD and XRCC1 gene polymorphism rare allele frequencies were observed to be higher than in the general population.

CONCLUSION

Pharmacogenetics might contribute to tailored therapy.

Tramadol or paracetamol do not effect the diagnostic accuracy of acute abdominal pain with significant pain relief - a prospective, randomized, placebo controlled double blind study

OBJECTIVES

To examine the effects of early administration of analgesics in patients with acute abdominal pain on pain severity, abdominal findings and diagnostic accuracy.

METHODS

210 patients with non-traumatic acute abdominal pain lasting less than 72 hours were enrolled to this trial. Patients were administrated by placebo, tramadol (1 mg/kg), or paracetamol (15 mg/kg) randomly after the first evaluation of pain severity scores (standard 100 mm visual analog scale) and abdominal findings (rebound, rigidity, tenderness). After 20 and 40 minutes of administrations, pain severity scores and abdominal findings were re-examined. Complete blood count, electrocardiography, plain abdominal x-ray, urine analysis and abdominal ultrasound were used for the initial diagnosis. The final diagnoses were decided after re-examinations, biochemical blood analysis, abdominal computed tomography in all patients and consultations or other diagnostic methods when necessary.

RESULTS

There were 70 patients in each group. Baseline pain severity scores and abdominal findings were similar at all groups. After 20 minutes, pain severity scores were decreased in tramadol and paracetamol groups compared with the placebo group as 55% and 45% vs 1% respectively (p < 0.001). After 40 minutes, decreases on pain severity scores were more significant at treatment groups, 67% and 60% vs 0 (p < 0.001). When compared to placebo tramadol and paracetamol increased the new onset or worsening nausea or vomiting. There was no difference on abdominal findings among the groups after 20 and 40 minutes examinations. Diagnostic accuracy of tramadol, paracetamol and placebo groups were 96%, 94% and 94% respectively.

CONCLUSIONS

Early administration of tramadol and paracetamol provided effective pain relief in patients with non-traumatic acute abdominal pain and those administrations did not interfere with diagnosis.

Recurrent rhinolithiasis: a case report with review of the literature

Rhinolith is an uncommon nasal mass and a rare entity encountered in clinical practice. The typical symptoms of rhinolith are unilateral nasal obstruction, foul smelling purulent nasal discharge and epistaxis, crusting, swelling of nose or face, anosmia, epiphora and headache. In this report, we present a case of recurrent rhinolith manifesting as an incidental finding on dental radiographs. A 26-year old male patient with a history of long standing halitosis had an operation for rhinolith seven years previously. Rhinolith in the right nasal cavity was diagnosed on rigid endoscopic examination. Rhinolith was removed by using a rigid nasal endoscope under local anaesthesia. To our knowledge, recurrence of rhinolith has not been described previously in the literature.

Multiple dural arteriovenous fistulas involving the cavernous sinus, transverse sinus, sigmoid sinus and spinal drainage: CT angiography findings in 14-year-old boy

Dural arteriovenous fistulas (DAVF) are rare and constitute 10% to 15% of all intracranial arteriovenous malformations. Only few cases of DAVFs are reported in children. Here is the first case report describing CT angiographic findings in a 14 year old child having multiple DAVFs involving spinal canal, both cavernous and cerebral sinuses.

A rare cause of ankle pain: concomitant intravenous lobular capillary haemangioma and arteriovenous fistula

Intravenous lobular capillary haemangioma (ILCH), also called intravenous pyogenic granuloma, is a rare benign lesion. These lesions are frequently showed themselves in the veins of the neck and upper extremities of young women. Clinical features are not specific. Ultrasonography can be used for diagnosis and showing additional pathologies such as arteriovenous fistula. The treatment is surgical excision. Correct pathologic diagnosis is required for differential diagnosis. We report an ILCH case presented to the Emergency Department with the complaints of pain and swelling in the ankle, originated from an arteriovenous fistula in vena saphena magna.

Evaluation of children with neurobrucellosis

BACKGROUND

Brucellosis is an endemic disease in many areas throughout the world. Central nervous system involvement is a serious complication of brucellosis with a ratio of 4-11% of all patients.

AIM

to describe our experience in diagnosis, treatment, and outcome of 25 pediatric patients with neurobrucellosis.

PATIENTS AND METHODS

This study included a review of medical records of patients who were diagnosed with neurobrucellosis between March 2001 and March 2009. Patients who had both clinical findings consistent with neurobrucellosis and positive microbiologic/serologic examinations of CSF with abnormal CSF findings were enrolled in the study.

RESULTS

The study included 25 patients between 1 and 15 years of age (mean 8.8 years), while 15 were males and 10 were females. Most of the patients (52 %) were in the age group of 5-9 years with male predominance. The distribution of cases showed density in June and February. The most commonly presented complaints were headache, fever and sweating while the most commonly observed findings were fever and meningeal irritation signs. All patients had positive cerebrospinal fluid agglutination test for brucellosis. Four different regimens were used based on ceftriaxone, doxycycline, cotrimoxasole, streptomycin, and rifampicin. One patient died, three patients were discharged with sequel, and the remaining patients (84 %) were discharged with full recovery.

CONCLUSION

Clinicians, especially those providing health services in endemic areas like Turkey, should keep in mind that neurobrucellosis can be involved in patients with unexplained symptoms like memory impairment or in patients diagnosed with meningitis (Tab. 5, Fig, 2, Ref. 39).

A 9-year follow-up of a girl with pyridoxine (vitamin B6)-dependent seizures: magnetic resonance spectroscopy findings

Being an extremely rare condition makes the diagnosis of pyridoxine-dependent seizures (PDS) difficult. Early diagnosis of PDS is very important to prevent unwanted clinical outcomes. Elevated levels of glutamate and decreased levels of y-aminobutyric acid (GABA) in the frontal and parietal cortices are detected in this disorder. Here we present an 18 year old girl with PDS, who was reported 9 years ago with Magnetic Resonance Spectroscopy (MRS) findings. Present and past MRS findings showed a decrease in N-acetyl-aspartate-to creatine ratio on MRS. In this case it is surprising that neuronal damage has been preceded despite the administration of accurate treatment. That can be because of delay in treatment and/or under treatment.

Malign peritoneal mesothelioma with nephrotic syndrome

Nephrotic syndrome may occur in malignancies like Hodgkin Disease and other solid tumors due to glomerulonephritis, amyloidosis or other causes. However, it is rare in peritoneal mesothelioma. We report a 42-year old female patient with peritoneal mesothelioma and nephrotic syndrome together with a review of literature (Tab. 1, Fig. 3, Ref. 7).