Journal of Research in Medical Sciences
Volume:11 Issue: 4, Jul & Aug 2006

Two new porphyrin-based magnetic resonance imaging (MRI) contrast agents, Gd-hematoporphyrin (Gd-H) and Gd-tetra-carboranylmethoxyphenyl-porphyrin (Gd-TCP) were synthesized and tested in nude mice with human melanoma (MM-138) xenografts as new melanoma contrast agents. Subcutaneous xenografts of human melanoma cells (MM-138) were studied in 30 (five groups of six) nude mice. The effect of different contrast agents (Gd-TCP, Gd-H, GdCl3 and Gd-DTPA) on proton relaxation times was measured in tumors and other organs. T1 values, signal enhancement and the Gd concentration for different contrast agent solutions were also investigated. The porphyrin agents showed higher relaxivity compared to the clincal agent, Gd-DTPA. A significant 16% and 21% modification in T1 relaxation time of the water in human melanoma tumors grafted in the nude mice was revealed 24 hours after injection of Gd-TCP and Gd-H, respectively. The percentage of injected Gd localized to the tumor measured by inductively coupled plasma atomic emission spectrometry (ICP-AES) was approximately 21% for Gd-TCP and 28% for Gd-H which were higher than that of Gd-DTPA (10%). The high concentration of Gd in the tumor is indicative of a selective retention of the compounds and indicates that Gd-TCP and Gd-H are promising MR imaging contrast agents for melanoma detection. Gd-porphyrins have considerable promise for further diagnostic applications in magnetic resonance imaging.

Drooping of the upper eyelid (blepharoptosis or ptosis) is not an uncommon ocular problem. The causes of ptosis could be myogenic, aponeurotic, mechanical or traumatic. Detailed assessments of the cause, degree of ptosis and levator functions help determine the most appropriate management and treatment. This study was carried out to investigate the causes and presentations of ptosis in patients in Yazd, Iran. Data from ptotic patients referred to the Eye Clinic of Shahid Rahnemoon Hospital were collected by questionnaires from September 2004 to September 2005 in a case series study. In total, 90 patients (42 males, 48 females) were included in the study. The most frequent types of ptosis were myogenic in 37 cases (41.1%), aponeurotic in 32 (35.6%), neurogenic in 12 (13.3%) and mechanical in 9 (10%), in the order mentioned. Of a total of 90 cases, 50 (55.6%) were congenital and 40 (44.4%) were acquired. Overall, only one side was involved in 65 cases (72.2%), while 25 (27.8%) cases had bilateral involvement. The most frequent type ofptosis was aponeurotic in men (19 patients or 45.2%) and myogenic in women (22 patients or 45.8%). Clinical aspects of ptosis were related to etiology. Our study showed that the most frequent type of ptosis was congenital myogenic type and its frequency was equal in both sexes.

Telomerase is a reverse transcriptase enzyme that synthesizes telomeric DNA on chromosome ends. The enzyme is important for the immortalization of cancer cells because it maintains the telomeres. Telomerase activity (TA) was measured by fluorescence-based telomeric repeat amplification protocol (FTRAP) assay in prostate carcinoma and benign prostatic hyperplasia (BPH). TA was present in 91.4% of 70 prostate cancers, 68.8% of 16 prostatic intraepithelial neoplasia (PIN), 43.3% of 30 BPH*, 21.4% of 14 atrophy and 20% of 15 normal samples adjacent to tumor. There was not any significant correlationbetween TA, histopathological tumor stage or gleason score. In contrast to high TA in the BPH* tissue from the cancer-bearing gland, only 6.3% of 32 BPH specimens from patients only diagnosed with BPH were telomerase activity-positive. These results indicate that TA is present in most prostate cancers. The high rate of TA in tissue adjacent to tumor may be attributed either to early molecular alteration of cancer that was histologically unapparent, or to the presence of occult cancer cells. Our findings suggest that the re-expression of telomerase activity could be one step inthe transformation of BPH to PIN.

Congenital hypothyroidism (CH) often seems to be associated with other congenital abnormalities, mostly cardiac in nature. The aim of this study was to determine the prevalence of cardiac malformations in patients with CH diagnosed during CH screening program in Isfahan. In this cross-sectional study, cardiac malformations were determined in CH patients were compared to controls using echocardiography. The association between cardiac malformations and mean T4 and TSH concentrations, etiology of CH according to radiologic findings and permanent and transient CH were studied in CH patients. Overall, 96 and 59 subjects were included in the case and control groups, respectively. Cardiac malformations were present in 30.2% (n = 29) and 15.2% (n = 9) of case and control groups, respectively; i.e. a higher prevalence in CH patients than in controls (P = 0.03). The prevalence of cardiac malformations without patent foramen oval was 6.25% (n = 6) in CH patients and 1.7% (n = 1) in control group (P = 0.1). There was no significant association between the presence of cardiac malformations and the aforementioned variables. High prevalence of cardiac malformations in CH patients strongly suggests the potential involvement of genetic factors in the pathogenesis of CH. This emphasizes on the necessity of genetic studies involving CH patients.

Since the evolution of multi-drug chemotherapy and radiotherapy and new sophisticated surgical techniques, limb salvage and reconstruction, rather than amputation, has become the preferred treatment for patients with bone tumors. One option is allograft replacement. Although allograft has several advantages, it is not without complications. This study was performed to observe these complications in a group of patients treated with allograft replacement for bone tumor resection. The purpose was to gain an overview of the factors predisposing to these complications to minimize their occurrence. This retrospective study was performed on patients with benign aggressive and malignant bone tumors undergoing limb reconstruction with allograft between 1997 and 2005 in Al-Zahra and Kashani Hospitals in Isfahan, Iran. Data was collected from patient files, clinical notes, radiographs and a recent physical examination. Complications includinglocal recurrence, fracture of allograft, fixation failure, nonunion, infection, skin necrosis and neurological damage were recorded. Sixty patients including 39 males and 21 females were studied. The mean age of patients was 23 ± 11.7 years. The mean follow-up interval was 28.1 ± 12.4 months (mean ± SD). Complications were allograft fracture in 20%, local recurrence in 16%, fixation failure in 11%, nonunion in 6%, infection in 6%, skin necrosis in 6%, and peroneal nerve palsy in 1% of cases. Most local recurrences (60%) were those with a mal-performed biopsy. Most allograftfractures occurred when a short plate was used. Allograft replacement for bone tumors remains a valid option. To avoid complications, biopsy should be done by a trained surgeon in bone oncology. A long plate is recommended for fixation. Sterility and graft processingmust be optimal. Autogenous bone graft must be added at host-allograft junction.

Head injury is still a major cause of death and disability. Despite advances in intensive monitoring and clinical practice, little data is available to show the predictive value of intracranial pressure monitoring in assessment of the outcome of head injuries. This study was undertaken to evaluate this predictive value and is the first Iranian study in which ICP monitoring has been included. In a prospective study from September 1999 to September 2003, all head- injured patients (53 patients) with GCS of 4-8 who were admitted to Nemazee Hospital of Shiraz University of Medical Sciences were included in this study. Subarachnoid screw method or ventricular catheter via ventriculostomy was used to determine intracranial pressure. Patients were monitored for 3 days and were followed for two years at 6-month intervals. Car accidents were the most common cause of head injury (43.3%) and 43.3% of patients had GCS of 8. Sixty percent of patients had abnormal intracranial pressure. The patients were most commonly in their first decade of life (18.8%) and 81% of patients were male. Controlling increased intracranial pressure was successful in 60% of patients and resulted in a decrease of mortality rate from 60% to 15%. Early treatment of increased intracranial pressure in head injury patients would be beneficial in reducing mortality and morbidity rates.

CD44 is a transmembrane glycoprotein involved in cell-cell and cell-matrix interactions. De novo expression of CD44 and its variant isoforms has been associated with aggressive behavior in various tumors. Since little data is available on the role of CD44 expression in renal cell carcinoma, we evaluated CD44 expression to determine its prognostic value. Forty-six patients with renal cell carcinoma were studied. CD44 expression was evaluated semiquantitively on paraffin-embedded tumor tissue by immunohistochemistry. The prognostic value of CD44 was tested using Kaplan Meier plots by the log rank test and Cox regression analysis. Fifteen out of 46 specimens (32.6%) were CD44-positive. According to bivariate analysis, tumor stage, tumor size, nuclear grade and CD44 expression were significant prognostic factors. CD44 expression can be considered as a useful prognostic parameter in renal cell carcinoma.

Lithium is transferred into the intracellular space mainly via sodium-lithium counter transport pathway. This pathway is under genetic control and acts variably in different ethnic groups. With respect to possible genetic differences in our target population compared to other populations, this study was designed to obtain knowledge on meanlithium ratio (LR) in this population so as to provide a benchmark for adjusting appropriate dosage of prescribed oral lithium and plasma concentration of lithium in clinical practice. In this study, 47 (26 male and 21 female) patients with bipolar disorders treated by lithium alone or in combination with other drugs at least for 2 weeks were selected by simple random sampling. Venous blood samples of selected patients were obtained and plasma and RBC lithium concentrations were measured. Finally, LR was determined using the atomic absorption method. Mean value of LR in the entire target population and in the group treated with lithium alone was 44.4 ± 23.22% and 58.52 ± 14%, respectively. In patients concomitantly treated with lithium and neuroleptic drugs, LR was significantly lower than that in all patients. LR in females was higher than that in males. LR in the group treated with lithium alone was significantly higher than figures reported in Europeans and Americans patients. These findings suggest that bipolar patients in this geographical zone of Iran should probably be treated with smaller doses of lithium to achieve optimal intracellular therapeutic levels of lithium, compared to levels regarded as therapeutic for Europeans and Americans.

Sudden sensorineural hearing loss (SSNHL) is a perplexing condition for patients and there are many controversies about its etiology, audiologic characteristics, prognostic factors, and treatment. In this prospective study, we performed some audiologic tests, including PTA, IA, ABR, and OAE (TEOAE) before beginning treatment of 53 patients with SSNHL. We assigned the patients randomly to two treatment groups: oral steroids + acyclovir vs. intravenous urographin. Twenty-eight patients underwent Magnetic Resonance Imaging (MRI) of the Brain. Of 53 patients (22 female and 31 male), 22 (41.5%) had negative or no signal to noise ratio and overall correlation in TEOAE. Twenty-six patients (49%) had positive overall correlations less than 50%, and 5 patients (4.4%) had overall correlations >50%. Fifteen patients (28. 3%) responded completely or well, 20 (37.7%) responded partially, and 18 (33.9%) had poor or no response to the treatment. The mean values for overall correlation in 3 subgroups of patients(no response, partial response, and complete response) were – 3. 5% (+ 1/16%), +11% (+ 1/99%), and +36.6% (+3/07%), respectively (P = 0.01). Twenty out of 52 patients had no reproducible wave in ABR (38.5%), and waves I, III, and V were absent in 40 (77%), 31 (59.6%) and 21 (40%) patients, respectively. There were some limitations (false positive and false negative results) in ABR use in our cases, but it may be useful in detecting site of lesion in SSNHL.Overall, according to the results of OAE, ABR, and brain MRI of these patients, 3 were affected by acoustic neurinomas, at least 1 had auditory neuropathy, and the site of lesion was cochlear in 6, and cochlear + retrocochlear in 13 patients. ABR has limitations for use in SSNHL and seems not to obviate the need for brain MRI, but may help in determining the site of lesions such as ischemia or neuropathy. Overall correlation (and S/N ratio) in TEOAE is a valuable prognostic factor in SSNHL, hence we recommend performing TEOAE in every patient with SSNHL.

Tuberculous brain cerebritis, abscess and tuberculoma in AIDS patients are considered as rare conditions and only few cases have been reported in the literature. The present case is a 28-year-old man with AIDS and previous systemic tuberculosis,denied by him and his family. He was admitted to our department due to headache, hemiparesis and seizures. A brain computed tomography (CT) scan disclosed a frontal hypodense lesion with a non-homogenous contrast enhancement that was reported as a high grade glioma. Magnetic resonance imaging (MRI) showed a diffuse hypointenselesion in right frontal area on T1-weighted, and hyperintense on T2-weighted and flair view, but there was a small paraventricular region with hypointensity on both T1, T2 and flair series, which was also reported to be a high grade glioma. Because of clinical course and imaging findings, the patient was a candidate for operation. After operation, the results of pathology and laboratory examination confirmed the diagnosis of tuberculous brain cerebritis and tuberculoma with positive Acquired Immune Virus (HIV) serology. Thus, tuberculous cerebritis, tuberculoma and abscesses should be considered in the differential diagnosis of focal brain lesions in AIDS patients, but AIDS should also be consideredin every patient with an uncommon cerebral lesion who is not cooperative with medical healthcare providers. Surgical excision or biopsy and anti-tuberculous treatment are the mainstay in management of these lesions in patients with AIDS.

Kidney disease is not a common complication in Down Syndrome (DS). A variety of renal and urologic problems have been described in these patients and some develop renal failure. Coincidence of polycystic kidney disease and DS is a rare entity. This is a report of a 3.5-month-old infant with DS, known to have early end-stage renal failure due to polycystic kidney disease.