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Group  streptococci (GÂS) are rare causes of myositis and myonecrosis involving adult patients in tropical regions. Streotococcal myositis is associated with a wide clinical spectrum, ranging from a subacute localized form with good prognosis to a serious acute presentation involving rapidly progressive disease, shock, multiple organ failure and a high case fatality rate (80-100%). Ïn this paper we present a 59 years old woman who was in good health before her last 5 days. Her illness presented with a very severs progressive pain of left arm .Her conditions progressed and worsened, despite of right diagnosis and beginning of treatment she died of multi organ failure. Postmortem biopsy of primary lesion of left arm revealed a diffused muscle necrosis with scattered microbial (cocci) cluster between muscle fibers. Çulture of primary blister was sterile but streptococcus group  was grown in blood culture.

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Background and purpose : Differentiating acute tubular necrosis (ATN) from prerenal azotemia is crucial for selecting the appropriate treatment. Since urinary diagnostic modalities are usually unreliable because of premedications, a rapid and accurate diagnostic modality is needed. This study was conducted to evaluate the diagnostic value of Doppler ultrasonography in differentiating ATN form prerenal azotemia in children.
Materials and methods :A total of 50 oliguric or anuric children with previous normal renal laboratory data entered in this study. Doppler examination and calculation of resistance index (RI) were performed within 24 hours of admission and in the recovery phase of ARF. Based on history, clinical follow-up and laboratory studies, diagnosis of underling cause of ARF was made and appropriate treatment started. The sensitivity and specificity of RI in differentiating ATN from prerenal azotemia were assessed.
Results :At the cut off points of RI=0.75, the sensitivity and specificity of RI in differentiating prerenal failure and ATN were 91.3% and 85.2%, respectively.
Conclusion: Doppler ultrasonography is helpful in differentiating ATN from prerenal azotemia in children. The cut-off value of 0.75 has the highest accuracy in diagnosis.

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Background and purpose: Despite the widespread use of silver nanoparticles, there are concerns about their biological effects on the environment and human health. The aim of this study was to investigate the cytotoxic effect of Ag+ nanoparticles on liver tissue and enzyme activities in NMRI mice. Materials and methods: In this experimental study, thirty five female NMRI mice were randomly divided into one control group and four experimental groups (n=7). The experimental mice, silver nanoparticles at concentrations of 50, 100, 200 and 400 mg kg were injected intraperitoneally (Every other day). Blood samples were taken from the inner corners of the eyes of mice and after separating the serum, liver enzyme activities were analyses. At the end of study, all animals were euthanized via cervical dislocation and tissue samples stained with hematoxylin and eosin for histopathology evaluation. Statistical analysis was performed using SAS software (P≤0.05) Results: Histopathological examination showed that different concentrations of Ag+ nanoparticles cause mild to severe injury (necrosis, inflammatory cell infiltration, and vacuolar degeneration) of the liver. The results showed that the activity of liver enzymes compared to the control group in all groups at a concentration of 400 mg/kg significantly (P≤0.05) increased. Conclusion: Our findings indicated that exposure to the different concentrations of Ag+ nanoparticles can cause severe damages in the mice's liver and increase of serum enzyme activities.

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Sickle cell disease is the most common type of hemoglobinopathies in the world that is caused by abnormal beta globin chain in hemoglobin. The disease is usually diagnosed in the first decade of life. Bone involvement is one of the most common clinical manifestations both in the acute setting (painful vaso-occlusive crises), and/or as a source of chronic disability (such as avascular necrosis). This paper introduces an old patient with advanced skeletal manifestation due to this disorder. A 66-year-old man who was opium abuser was visited by a rheumatologist for lower limbs pain, and fatigue from one year ago. The patient had severe anemia, and X-ray revealed diffuse osteolytic changes without sharp border in pelvis and femur and joint space narrowing. Involvement of thoracolumbar vertebras were seen as codfish vertebra appearance. In peripheral blood smear, sickle cell and target cells accompanied by hypochromia and platelets aggregation were detected. The hemoglobin electrophoresis was compatible with sickle-β+ thalassemia. In old patients with anemia and osteolytic lesions with unknown reason, evaluation of hemoglobinopathies, especially sickle cell anemia is suggested. 

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Bisphosphanates include a group of medicines used in treatment of specific bone diseases, such as multiple myeloma and osteo- high metastatic cancers. Though the exact mechanism of such medicines has not yet been known, the role these medicines play in the suppression of innervations and bone remodeling has been proved. Bisphosphonate related osteonecrosis of jaws (BRONJ) is a complication caused by using Bisphosphanates. It is a rare infliction, but, when it occurs, it brings about grave consequences for the patients including pathological fractures in the mandible. The BORNJ prevalence in patients who take intravenous Bisphosphates (BPs), such as Zolendronate, and Pamidronate is significantly higher than that in patients taking such medicines orally. The probability of BRONJ onset in mandible is twice higher than in maxilla; and some 60-70% of the patients are reported to be inflicted with BRONJ following dental surgeries. The signs and symptoms may occur prior to the presence of osteonecrosis, which include pain, loose teeth, and membranous lesions. The imaging features in BRONJ are non-specific. Peri-apical and panoramic imaging are the primary screening indices, while CT scanning and MRI provide us with more accurate information. Nonsurgical treatment protocols include anti-pain medicines, antibiotics, and anti-microbial mouthwashes, while surgical treatments include debriding and resection which are being suggested in more advanced cases.