Pathophysiology of preeclampsia: linking placental ischemia/hypoxia with microvascular dysfunction

Studies during the past decade have provided a better understanding of the potential mechanisms responsible for the pathogenesis of preeclampsia. The initiating event in preeclampsia has been postulated to be reduced uteroplacental perfusion as a result of abnormal cytotrophoblast invasion of spiral arterioles. Placental ischemia/hypoxia is thought to lead to widespread activation/dysfunction of the maternal vascular endothelium which results in enhanced formation of endothelin, thromboxane, and superoxide, increased vascular sensitivity to angiotensin II, and decreased formation of vasodilators such as nitric oxide and prostacyclin. These endothelial abnormalities, in turn, cause hypertension by impairing renal function and increasing total peripheral resistance. While recent studies support a role for cytokines and other factors such as lipid peroxides and reactive oxygen intermediates as potential mediators of endothelial dysfunction, finding the link between placental ischemia/hypoxia and maternal endothelial and vascular abnormalities remains an important area of investigation. The quantitative importance of the various endothelial and humoral factors in mediating the vasoconstriction and elevation in arterial pressure during preeclampsia has also not been completely elucidated.     

Alpha interferon in children with Philadelphia chromosome-positive chronic myeloid-leukaemia

The present work focuses on the therapeutic efficacy and the toxicity of alpha interferon in patients younger than age 18 years. 5 patients younger than 18 years were treated and followed up between 1990 and 1999 at the department of haematology (Aziza Othmana Hospital) Hydroxyurea was given as initial treatment to all patients. After a median period of 8 months, these patients received alpha interferon (5 millions units/m2 once). Six months after the beginning of the alpha interferon a complete hematologic response was obtained in all patients. The median overall survival was of 66 months: 3 patients are still alive (2 patients in an advanced stage and one patient in chronic phase) and 2 patients died after transformation. The most common reported side effects of alpha interferon were asthenia, weight loss, fever, myalgia, chills and headaches--these toxic manifestations were mild and were noticed in all our patients. Myelosuppression was noted in two patients. Interferon is well tolerated in patients younger than age years 18 old, with CML. It may offer an alternative to bone marrow transplantation in children in the chronic phase of CML without histocompatible donor. The role of new agents such as STI 571 needs to be evaluated as well.     

Embolization of head and neck hypervascular lesions. A retrospective study of 5 cases

Embolisation of head and neck hypervascular tumours and arterioveinous malformations (AVMs) is now a well-established therapeutic procedure. The purpose of this study was to analyse the technique and to evaluate the safety and value of preoperative embolization of hypervascular lesions. We retrospectively reviewed the records of 5 patients, agged between 14 and 47 years, with hypervascular tumours and AVMs in the head and neck. Lesions were distributed as follow: nasal angiofibroma (n = I), nasal angioleiomyoma (n = I), nasopharyngeal angiofibroma (n = I), aneurysmal bone cyst in the posterior element of the second cervical vertebra (n = I) and AVM of the inferior lip (n = I). Angiography and embolization were carried out at the same time. Complete exclusion of lesions was obtained without any complications. Complementary surgical resection was performed with not notable blood loss.     

Uterin choriocarcinoma revealed by pulmonary metastasis. A case report

Uterine choriocarcinoma is a rare trophoblastic tumor, characterized by its metastatic potentiality and its sensitivity to chemotherapy. Pulmonary metastases are frequent, but they rarely reveal the disease. We report the case of a 30-year-old patient with uterine choriocarcinoma. The disease occurred after a normal delivery and was revealed by a pulmonary metastasis. Through of this case and a review of literature, we remind of the diagnostic and prognostic particularities of uterine choriocarcinoma.     

Epithelioid hemangioendothelioma of bone complicated by femoral fracture

A 54-year-old man was seen with a fracture of the left femur. Plain radiographs revealed a 40-mm lytic centromedullary lesion. Magnetic resonance T1- and T2-weighted sequences showed high and low signals. After stabilization of the fracture, the tumor was removed followed by reconstruction with a vascularized fibula. The pathological examination demonstrated proliferation of non atypical CD34 and CD31 positive epithelioid cells with few lumens, accompanied by abundant fibrous stroma, sometimes masking tumor cells. Satisfactory motion was achieved with no recurrence at 20 months follow-up. Bone hemangioendothelioma can simulate metastasis and must be distinguished by immunohistochemistry. Prognosis is a subject of debate as the tumor is considered to exhibit intermediate malignancy by some authors while other consider it to be a malignant tumor.     

A comparative study between ciliary count and the degree of opacity of paranasal sinus CT scans in chronic sinusitis pre and post FESS

OBJECTIVE: To investigate the relationship between the extent of sinus disease in chronic sinusitis as detected radiologically by computed tomography (CT) scan and the population of cilia (ciliary area) both before and after functional endoscopic sinus surgery (FESS). In a simple way this is a trial to statistically prove that the CT scan could be a valid indicator and a mirror of the histological status of the sinus mucosa. DESIGN: Twenty adult patients were enrolled in this study. Radiological extension of the sinus disease was quantitated using the classification proposed by Kennedy in 1992 and the ciliary population was studied using scanning electron microscopy and image analysis softwares. RESULTS AND CONCLUSION: The more advanced the sinusitis, as evidenced by CT scans, the more the expected reduction in the ciliary area (CA) and in the ciliary count. But after FESS the degree of ciliary regeneration does not depend statistically on the radiological condition of the sinuses and the degree of opacity prior to intervention, i.e. a statistically valid inverse relationship exists between the radiological stage of sinusitis and the ciliary population pre-operatively but the same relation does not extend to the ciliary population post-operatively.     

Sex hormones as potential modulators of vascular function in hypertension

The greater incidence of hypertension in men and postmenopausal women compared with premenopausal women has suggested gender differences in vascular function. Vascular effects of the female sex hormones estrogen and progesterone and the male hormone testosterone have been described. Sex steroid receptors have been identified in vascular endothelium and smooth muscle. Interaction of sex hormones with cytosolic/nuclear receptors initiates long-term genomic effects that stimulate endothelial cell growth but inhibit smooth muscle proliferation. Activation of sex hormone receptors on the plasma membrane triggers nongenomic effects that stimulate endothelium-dependent vascular relaxation via NO-cGMP, prostacyclin-cAMP, and hyperpolarization pathways. Sex hormones also cause endothelium-independent inhibition of vascular smooth muscle contraction, [Ca2+]i, and protein kinase C. These vasorelaxant/vasodilator effects suggested vascular benefits of hormone replacement therapy (HRT) during natural and surgically induced deficiencies of gonadal hormones. Although some clinical trials showed minimal benefits of HRT in postmenopausal hypertension, the lack of effect should not be generalized because it could be related to the type/dose of sex hormone, subjects' age, and other cardiovascular conditions. The prospect of HRT relies on continued investigation of the molecular mechanisms underlying the vascular effects of sex hormones and identification of compounds that specifically target the vascular sex hormone receptors. Naturally occurring hormones and phytoestrogens may be more beneficial HRT than synthesized compounds. Also, the type/dose, time of initiation, and duration of HRT should be customized depending on the subject's age and preexisting cardiovascular condition, and thereby enhance the outlook of sex hormones as potential modulators of vascular function in hypertension.     

Transverse fracture of the sacrum: value of imaging. A case report

Transverse fractures of the sacrum with major displacement are rare and often misdiagnosed. A case of transverse fracture of the sacrum with cauda equina injury is reported. The diagnosis was not recognized initially. Conventional radiographs of the pelvis failed to demonstrate the fracture. True lateral sacral views and CT scan with reconstructions allowed analysis of the different sagittal fracture lines to facilitate surgical planning. These examinations should be considered in all patients with history of high energy trauma and clinical signs indicating lumbosacral injury.     

Concomitant alar and apical ligament avulsion in atlanto-axial rotatory fixation. Case report and review of the literature

The authors report a case of Fielding type II acute atlanto-axial rotatory fixation (AARF). The CT scan with coronal reconstruction showed an avulsion of the apical and right alar ligament. These findings are exceptionally reported in the literature, especially concerning the apical ligament which might be a stabiliser in flexion and extension of the occipitocervical joint.     

Causes of persistent obstructive sleep apnea despite previous tonsillectomy and adenoidectomy in children with down syndrome as depicted on static and dynamic cine MRI

OBJECTIVE: Our purpose was to evaluate the causes of persistent obstructive sleep apnea despite previous tonsillectomy and adenoidectomy in children with Down syndrome as depicted on cine MRI. MATERIALS AND METHODS: Cine MRI studies performed to evaluate persistent obstructive sleep apnea despite previous tonsillectomy and adenoidectomy were reviewed. MRI was performed under sedation and included cine MR images (fast gradient-echo) obtained in the midline sagittal plane and in the axial plane at the base of the tongue and T1-weighted spin-echo and fast spin-echo inversion recovery images in the axial and sagittal planes. Imaging parameters reviewed included static and dynamic diagnoses made, frequency of recurrence and diameter of tonsillar tissue, and tongue morphology. RESULTS: Twenty-seven patients were identified (mean age, 9.9 years). Diagnoses included glossoptosis in 17 patients (63%), hypopharyngeal collapse in six (22%), recurrent and enlarged adenoid tonsils in 17 (63%), enlarged lingual tonsils in eight (30%), and macroglossia in 20 (74%). Of the 20 patients with macroglossia, 11 (55%) had absence of the normal median sulcus and 12 (60%) had evidence of fatty infiltration of the tongue musculature. CONCLUSION: Persistent obstructive sleep apnea in children with Down syndrome who have undergone previous adenoidectomy and tonsillectomy has multiple causes. The most common causes include macroglossia, glossoptosis, recurrent enlargement of the adenoid tonsils, and enlarged lingual tonsils.