GJB2 mutations: passage through Iran

Hereditary hearing loss (HHL) is a very common disorder. When inherited in an autosomal recessive manner, it typically presents as an isolated finding. Interestingly and unexpectedly, in spite of extreme heterogeneity, mutations in one gene, GJB2, are the most common cause of congenital severe-to-profound deafness in many different populations. In this study, we assessed the contributions made by GJB2 mutations and chromosome 13 g.1777179_2085947del (the deletion more commonly known as del (GJB6-D13S1830) that includes a portion of GJB6 and is hereafter called Delta(GJB6-D13S1830)) to the autosomal recessive non-syndromic deafness (ARNSD) genetic load in Iran. Probands from 664 different nuclear families were investigated. GJB2-related deafness was found in 111 families (16.7%). The carrier frequency of the 35delG mutation showed a geographic variation that is supported by studies in neighboring countries. Delta(GJB6-D13S1830) was not found. Our prevalence data for GJB2-related deafness reveal a geographic pattern that mirrors the south-to-north European gradient and supports a founder effect in southeastern Europe.     

Prognostic Indicators for Squamous Cell Carcinoma of the Oral Cavity: A Clinicopathologic Correlation

Fifty-three patients with T1 squamous cell cancer of the floor of mouth and ventral surface of the tongue with a known clinical outcome were retrospectively analyzed and arbitrarily divided into “aggressive” and “nonaggressive” groups based on their clinical behavior. Various host and tumor factors were then evaluated in an attempt to determine whether the tumor behavior could have been predicted. The paraffin-embedded tumor specimens were evaluated for tumor differentiation, tumor thickness and tumor invasion, microvessel density, and p53 expression. In addition, a composite morphologic grading score was obtained by combining cell differentiation, nuclear polymorphism, mitosis activity, depth of infiltration, type of infiltration, and lymphatic infiltration. No single technique appeared capable of identifying “aggressive” behavior, although possibly an evaluation of composite factors might show promise in the future.     

Characteristic expression profiles induced by genotoxic carcinogens in rat liver.

When applied in toxicological studies, the recently developed gene expression profiling techniques using microarrays, which brought forth the new field of toxicogenomics, facilitate the interpretation of a toxic compound's mechanism of action. In this study, we investigated whether genotoxic carcinogens at doses known to induce liver tumors in the 2-year rat bioassay deregulate a common set of genes in a short-term in vivo study and, if so, whether these deregulated genes represent defined biological pathways. Rats were dosed with the four genotoxic hepatocarcinogens dimethylnitrosamine (4 mg/kg/day), 2-nitrofluorene (44 mg/kg/day), aflatoxin B1 (0.24 mg/kg/day), and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK, 20 mg/kg/day). After treatment for up to 14 days, the expression profiles of the livers were analyzed on Affymetrix RG_U34A microarrays. Among the significantly upregulated genes were a set of target genes of the tumor suppressor protein p53, indicating a DNA damage response. Such a response was expected and, therefore, confirmed the validity of our approach. In addition, the gene expression changes suggest a specific detoxification response, the activation of proliferative and survival signaling pathways, and some cell structural changes. These responses were strong throughout the 14 day time course for 2-nitrofluorene and aflatoxin B1; in the case of dimethylnitrosamine and NNK, the effects were weakly detectable at day 1 and then increased with time. For dimethylnitrosamine and aflatoxin B1, which caused observable inflammation in vivo, we found a corresponding upregulation of inflammatory genes at the same time points. Thus, by the toxicogenomic analysis of short-term in vivo studies, we identified genes and pathways commonly deregulated by genotoxic carcinogens, which may be indicative for the early events in tumorigenesis and, thus, predictive of later tumor development.     

Evaluation of the performance of general emergency physicians in pediatric emergencies: Obstructive airway diseases,seizures, and trauma

BACKGROUND: In the Lübeck region, as is usual in Germany, hospital-based emergency physicians are called for outside emergencies. They evaluate and stabilize patients and transfer them to hospital facilities of their choice (no emergency department system). These physicians are mainly anesthesiologists, surgeons, and internists-not pediatricians. Numerous quality management studies have shown an overall excellent performance of this system, but it has not been evaluated for pediatric emergencies. PATIENTS AND METHODS: In a prospective, observational study conducted over a 1-year period, all pediatric emergencies (patient age < 15 y) treated by the emergency physician service were studied. A syllabus with standards of care for children with trauma, obstructive airway disease, and seizures was distributed. In accordance with this syllabus, the actions taken were documented by the emergency physicians, and the cases were documented as life threatening or not and were classified as "trauma," "obstructive airway disease," "seizures," or "other" by the admitting pediatric intensivists and surgeons. The admitting attending physician compared these data and evaluated whether the standard management required by the syllabus was followed. RESULTS: A total of 422 pediatric cases out of 11,605 emergencies (3.5%) were recorded (147 [34.8%] trauma patients, 41 [9.7%] patients with obstructive airway disease, and 108 [25.6%] patients with seizures). Of the pediatric patients, 20.5% had life-threatening conditions; three children died before arrival, and the others required treatment in the intensive care unit. In 25% of trauma patients, deficiencies in primary treatment were observed: no documentation of neurologic status in 10.6%, no cervical immobilization in 15% of head trauma patients, and no adequate analgesia in 7%. In 25% of seizure patients, neurologic status was not documented, although treatment was in accordance with the standard of care. The worst results were observed in infants with obstructive airway disease: no documentation of oxygen saturation in 71.4%, no oxygen therapy despite hypoxemia in seven of 12 patients, and overall therapy not in accordance with the standard of care in 50%. CONCLUSIONS: The high quality of the emergency physician service documented for adults is not reproduced in the pediatric population. Trauma and seizures with similarities to adult cases are handled in a fair manner. However, the most important pediatric diagnostic entity of obstructive airway disease is often not treated adequately. Intensified educational programs for emergency physicians are warranted.     

Sirolimus-induced drug fever and ciclosporin-induced leukencephalopathia with seizures in one liver transplant recipient

We describe the first case of sirolimus-induced drug fever in a female liver transplant recipient, with a history of hepatitis C-induced end-stage liver cirrhosis in 1999. In 2005, six years after transplantation, she developed calcineurin inhibitor-induced renal function impairment. Immunosuppression was switched from tacrolimus to sirolimus. Two days after the intake of sirolimus, she developed daily fever spikes, but no infectious focus was found. Antibiotic therapy had no influence on the fever. After fourteen days, sirolimus was switched back to tacrolimus and the fever disappeared. In history, the patient developed ciclosporin-induced generalized seizures eleven days after liver transplantation, followed by the development of a motoric speech disorder. Magnetic resonance imaging （MRI） findings were consistent with leucoencephalopathy, therefore immunosuppressive therapy was changed from ciclosporin to tacrolimus and the neurologic symptoms improved significantly. Our case is the first reported case of sirolimus-induced drug fever. In addition, the patient showed the rare occurrence of ciclosporin-induced leukencephalopathy with seizures.     

Destabilization of acrosome and elastase influence mediate the release of secretory phospholipase A2 from human spermatozoa

Aim： To determine the cellular distribution of secretory phospholipase A2 （sPLA2） in dependence on the acrosomal state and under the action of elastase released under inflammatory processes from leukocytes. Methods： Acrosome reaction of spermatozoa was triggered by calcimycin. Human leukocyte elastase was used to simulate inflammatory conditions. To visualize the distribution of sPLA2 and to determine the acrosomal state, immunofluorescence techniques and lectin binding combined with confocal laser scanning fluorescence microscopy and flow cytometry were used. Results： Although sPLA2 was detected at the acrosome and tail regions in intact spermatozoa, it disappeared from the head region after triggering the acrosome reaction. This release of sPLA2 was associated with enhanced binding of annexin V-fluoroscein isothiocyanate （FITC） to spermatozoa surfaces, intercalation of ethidium-homodimer I, and binding of FITC-labelled concanavalin A at the acrosomal region. Spermatozoa from healthy subjects treated with elastase were characterized by release of sPLA2, disturbance of acrosome structure, and loss of vitality. Conclusion： The ability of spermatozoa to release secretory phospholipase A2 is related to the acrosomal state. Premature destabi- lization of the acrosome and loss of sPLA2 can occur during silent inflammations in the male genital tract. The distribution pattern of sPLA2 in intact spermatozoa might be an additional parameter for evaluating sperm quality.