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M Jan

Publications and source records attributed to M Jan.

At least 19 recordsLinked to original sources
PubMed2001

[French neurosurgery in the Bosnia-Herzegovina conflict].

Seven French neurosurgical missions, from June 1994 to December 1996, were sent successively to Bosnia-Herzegovina with the help of a non-governmental organisation Médecins du Monde. The aim of this article is to present the working conditions, make an overall evaluation of the missions and then to draw lessons and discuss the limits. The initial aim of these neurosurgical missions was: i) to provide human and logistic support to the Bosniac teams in the field; ii) to exchange knowledge and help in the training of local young neurosurgeons; iii) to be present as witnesses. The towns of Tuzla and Zenica in Eastern and Central Bosnia respectively were chosen as the missions bases. One hundred five neurosurgical operations were carried out in precarious conditions, particularly concerning anesthesia. The largest number of the operations (52%) concerned standard neurosurgical pathologies, without any direct link to the war but which had been put off or made difficult due to the war. Cranioplasties and peripheric nerve injuries were the main lesions directly related to the war situation which the French missions had to deal with. Actually, war neurosurgical pathologies were very often dealt with in emergency by Bosniac teams in the field hospitals near the front. Previously existing neurosurgical environment, in particular with access to a scanner is an absolute necessity to carry out a good quality neurosurgical mission. Precarious anesthesia and operating conditions require the surgical team to adapt to local conditions, but are not a contra-indication to such missions. Although help in the field can prove useful on occasions, training the resident teams is important. This can be done locally, but additional training in a neurosurgically developed country is fundamental. Missions such as these require relatively major funding (about 150 000 French francs for each of our missions) and suitable infrastructures. Prior to undertaking this type of mission, a neurosurgeon must evaluate local human and equipment needs.

Bosnia and Herzegovina↗
PubMed2001

Marked antitumor activity of a new potent acronycine derivative in orthotopic models of human solid tumors.

S 23906-1 is a novel acronycine derivative selected on the basis of its potency in vitro. We investigated the antitumor activity of S 23906-1 against several murine transplantable tumors (C38 colon carcinoma, P388 leukemia, B16 melanoma, and Lewis lung carcinoma) and in orthotopic models of human lung (NCI-H460 and A549), ovarian (IGROV1 and NIH:OVCAR-3), and colorectal cancers (HCT116 and HT-29). Against established C38 colon carcinoma, S 23906-1 administered twice i.v. from 1.56-6.25 mg/kg markedly inhibited tumor growth. Treatment at the optimal dose (6.25 mg/kg) induced tumor regression in all of the mice. Acronycine was 16-fold less potent and only moderately active at the maximum tolerated dose, 100 mg/kg. Against other murine tumors of the former National Cancer Institute panel, S 23906-1 was either only moderately active or totally inactive. When evaluated in human orthotopic models, S 23906-1 given p.o. or i.v. demonstrated a marked antitumor activity against human carcinomas. In the two human lung cancer models, S 23906-1 increased the survival of the animals in a dose-dependent manner and induced treated versus control values of 162% (NCI-H460) and 193% (A549). Vinorelbine was less active, with treated versus control values of 119% and 174%, respectively. A significant survival benefit was also observed against the two i.p. ovarian tumors in which S 23906-1 was as active as paclitaxel, inducing 80% long-term survivors in the NIH:OVCAR-3 model. Lastly, S 23906-1 inhibited the growth of primary HT-29 and HCT116 colon tumors grafted onto the cecum as efficiently as irinotecan and eradicated the formation of lymph node, hepatic, and pulmonary metastases in the aggressive HCT116 model. The novel spectrum of activity of S 23906-1 compared with existing anticancer agents warrants further preclinical investigation.

Acronine↗
PubMed2001

[Role of high-dose chemotherapy with hemopoietic stem-cell support in the treatment of adult patients with high-grade glioma].

Despite surgery, post-operative irradiation and adjuvant conventional chemotherapy, prognosis of high-grade gliomas remains poor. Carmustine (BCNU) has been shown to have limited activity at conventional dosage but is still the standard chemotherapy. Activity of chemotherapy is limited by the blood-brain barrier impermeability and high levels of expression of multidrug resistance proteins on tumor and/or endothelial cells. Despite high response rates, development of intra-arterial chemotherapy remains limited because of frequent acute brain toxicity related to drug administration. High-dose intravenous chemotherapy rescued by autologous hemopoietic stem cell transplantation is an alternative that might increase drug delivery through the blood-brain barrier and tumor control. Several phase I-II trials using high-dose BCNU were published. The maximum tolerated dose seems to be 800 mg/m2 and interstitial pneumonitis and hepatitis are dose-limiting toxicities. Few phase I-II trials of high-dose therapy were published using drug combinations. High response rates in patients with progressive tumor were observed and in adjuvant setting, encouraging results in terms of median survival time and long survivors were published. No phase III trial was reported to date. Future investigations should include randomized trials comparing high-dose and conventional-dose chemotherapy and development of new high-dose regimens that incorporate new drugs such as temozolomide.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2000

Cavernous sinus invasion by pituitary adenoma: MR imaging.

PURPOSE: To define magnetic resonance (MR) imaging criteria for the diagnosis of cavernous sinus invasion by pituitary adenoma. MATERIALS AND METHODS: The MR images obtained in 106 patients (86 female, 20 male; age range, 16-71 years) were reviewed retrospectively by two physicians. The standard-of-reference criteria for invasion were the surgical findings. A chi(2) analysis was performed, and the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for nine groups of MR imaging signs were computed. RESULTS: Invasion of the cavernous sinus was certain (PPV, 100%) if the percentage of encasement of the internal carotid artery (ICA) by tumor was 67% or greater. It was highly probable if the carotid sulcus venous compartment was not depicted (PPV, 95%) or the line joining the lateral wall of the intracavernous and supracavernous ICAs was passed by the tumor (PPV, 85%). It was definitely not invaded (NPV, 100%) if the percentage of encasement of the intracavernous ICA was lower than 25% or the line joining the medial wall of the intracavernous and supracavernous ICAs was not passed by the tumor. CONCLUSION: The radiologic diagnosis of cavernous sinus invasion by pituitary adenoma remains difficult, but the above-mentioned criteria may be of assistance.

Adenoma↗
PubMed2000

Histology and sensitivity to anticancer drugs of two human non-small cell lung carcinomas implanted in the pleural cavity of nude mice.

We have established two metastatic models of human non-small cell lung carcinoma (NSCLC)-the NCI-H460 large-cell carcinoma and the A549 adenocarcinoma-by inoculating tumor cells into the pleural space of nude mice. The objectives of this work were as follows: (a) to study the histological characteristics and growth and dissemination patterns of these tumors in nude mice; (b) to assess their sensitivity to drugs that have demonstrated significant clinical therapeutic effect in the treatment of NSCLC; and (c) to investigate the antitumor activity of S 16020-2, a new olivacine derivative, currently in Phase II clinical evaluation. In each of the two models, all animals developed lung tumors, resulting in 100% mortality. Histopathological study showed that these two tumors spread locally to contiguous structures, including the mediastinal pleura and diaphragm, with histological characteristics consistent with the human pathology. Anticancer drugs used for the treatment of NSCLC, such as cisplatin, doxorubicin, vinblastine, and etoposide, enhanced the life span of treated mice in the two models and were more active in the NCI-H460 than in the A549 model. The increases of survival time as compared to control groups were from 60 (P < or = 0.05) to 83% (P < or = 0.01) and from 21 to 40% for NCI-H460 and A549, respectively. Vinorelbine, paclitaxel, and irinotecan showed similar activities in the two models and increased the survival of treated mice by between 38 and 79% (P < or = 0.001) and between 58 (P < or = 0.01) and 78% in the NCI-H460 and A549 models, respectively. However, none of these drugs was curative, reflecting the resistance of this disease to chemotherapy. S 16020-2 exhibited a remarkable antitumor activity, increasing the survival by 82% (P < or = 0.01) for NCI-H460 and by 126% (P < or = 0.001) for A549. This drug was among the most active compounds in these models, thereby indicating its potential for the chemotherapy of this disease.

Animals↗
PubMed2000

[Evaluation of motor speech function in the diagnosis of various forms of dysarthria].

Perceptual analysis is not sufficient enough to identify specific dysarthria types. In order to improve the discrimination between dysarthria types, we developed a standardized evaluation of different functions controlling speech motor performances. This was applied to 90 patients suffering from hypokinetic, spastic or ataxic dysarthria and 15 control subjects. A discriminate analysis showed that 71.4 p. 100 of the cases were correctly classified. This model was validated within a new group of 21 patients and showed that the less severe dysarthric parkinsonian patients were difficult to distinguish from control subjects. The discriminate analysis was then used for 20 patients with atypical parkinsonism. Seven patients with progressive supranuclear palsy were considered to have hypokinetic dysarthria. The 6 patients with multisystem atrophy and 7 with corticobasal degeneration were classified among the 3 dysarthric types. We suggest that motor speech evaluation may contribute to differential diagnosis within groups of patients suffering from atypical parkinsonism.

Aged↗
PubMed2000

Introduction

Explore the source record for details and available documents.

Journal Article↗
PubMed2000

[Pituitary disorders in pregnancy].

During pregnancy there is a normal increase in the volume of the anterior pituitary as demonstrated by MRI and hormone secretions which increase (PRL) or decrease (FSH, LH). During pregnancy pituitary adenomas, especially prolactinomas, may evolve as in non-pregnant women (microadenomas) or differently (macroadenomas). In 35 % of cases macroprolactinomas worsen during pregnancy making their medico-surgical management mandatory prior to pregnancy. Inversely, pregnancy occurring in a subject with a microprolactinoma never induces severe local complications so such tumors may be managed surgically or medically. Surgery should be performed for acromegaly or Cushing's disease before or early in pregnancy. Subacute pituitary apoplexy (intratumoral hemorrhage) occurs in about 10 to 15 % of adenomas but, generally speaking, clinical symptoms remain mild in pregnant women. Lymphocytic hypophysitis occurs at the end of pregnancy, or during the post-partum period. The association of complete pan-hypopituitarism and hypersignal on MRI examination may mimic hypophyseal apoplexy and could lead to and inappropriate surgical procedure.

Female↗
PubMed2000

[Vascular cerebral thrombosis during pregnancy and post-partum].

Pregnancy and puerperium are associated with a number of cerebrovascular conditions that may result in stroke. Those include cerebral venous thrombosis and cerebral arteries occlusions. Comparing stroke rates during pregnancy with those of non-pregnant women showed only a marginal excess risk during pregnancy and puerperium. Strokes due to cerebral venous thrombosis represent 10-20 per 100 000 deliveries in western countries. The cause of intracranial venous thrombosis is usually unknown. However, better understanding of abnormalities in coagulation leading to intravascular clotting in the early puerperium is resulting in better understanding of this disease. Nevertheless, an etiological work up should be performed, particularly when the thrombosis occurs during pregnancy. Its clinical manifestations often include focal neurological signs, seizures and headache. Alterations in consciousness occur as intracranial pressure increases. Arterial occlusions account for about 60% to 80% of cerebral ischemic lesions. A probable cause of ischemic stroke is diagnosed on the basis of clinical, biological and radiological data. Eclampsia is the main cause of nonhemorrhagic stroke. A search for rare causes of stroke linked to pregnancy such as post-partum cardiomyopathy, paradoxical embolism, choriocarcinoma, cardiac and hematological disorders may be appropriate.

Female↗
PubMed2000

[Surgical strategy in Cushing's disease].

Cushing's disease is almost always due to ACTH hypersecretion by a pituitary adenoma. Surgical excision is the only curative treatment. MRI together with ACTH assay in the inferior petrous sinus provides the diagnosis and localization in 80% of cases. Surgery should be wide in all cases, going beyond the limits of the adenoma visible on the MRI. Total or subtotal antihypophysectomy may be indicated if the imaging is negative and no lateralization can be determined from ACTH assays. In case of therapeutic failure, reoperation must be proposed early. A 5-year follow-up is required before the definitive results of surgery can be assessed. Cure is evaluated on the basis of postoperative cortisol levels (<3 - 5 g/dl). Initially, the rate of remission varies from 70 to 85%. Success after a second operation is to the order of 80 to 90%. The surgical risk for ACTH adenomas is higher than for other secreting adenomas (CSF fistulae, meningitis, thromboembolism, visual disorders), certainly due, in part to subtotal or total antihypophysectomy.

Adenoma↗
PubMed2000

[Prolactinoma in man: clinical and histological characteristics].

Prolactinoma usually occurs a small intrasellar tumor in women or as a large tumor in men. To determine whether the predominance of macroprolactinomas in men is due to a delay in diagnosis as has been suggested, or whether there is a sex-related difference in growth rate we conducted a retrospective study in 45 men and 51 women with prolactinomas. Preoperative prolactin level (PRL) was 2,789 573 ng/ml and mean tumor size was 26 2 mm. Prolactin levels and tumor size were significantly higher in women (292 74 ng/ml and 10 1 mm; p<0.01). There was no correlation with age at diagnosis or duration of symptoms. Giant tumors were only observed in men (n=8). Frequency of resistance to bromocriptine (30% vs 5%, p<0.01) and invasive tumors (52% vs 27%, p<0.001) were significantly higher in men than in women. Likewise, proliferation rate was higher for the prolactinomas in men (Ki-67: 2.6 1.1% positive nuclei vs 0.4 0.2%; p=0.08; PCNA: 5.0 2.3% vs 3.7 1.1%). In conclusion, prolactinomas in men are more aggressive than in women. They grow rapidly, often invade the cavernous sinus and are resistant to bromocriptine; proliferation rates can be increased.

Adolescent↗
PubMed2000

[MRI diagnosis of cavernous sinus invasion by pituitary adenomas].

Several MRI signs are helpful for the preoperative MRI diagnosis of cavernous sinus invasion by an adenoma. The first step is to analyse the percentage of encasement of the intracavernous ICA by the adenoma. If this percentage is greater than or equal to 66%, the cavernous sinus is invaded. If the percentage of encasement of intracavernous CA is less than 25%, the cavernous sinus is not invaded. If the percentage of encasement is between 25 and 66%, the analysis of the cavernous venous compartment, the drawing of intercarotid lines and the analysis of the shape and venous compartments of the cavernous sinus are necessary. The cavernous sinus invasion remains very likely if the carotid sulcus venous compartment is obliterated, or if the lateral intercarotid line is crossed. Conversely, if the median intercarotid line is uncrossed, the superior venous compartment is visible, the cavernous sinus is of normal size, or there is no bulging of its lateral dural wall, invasion of the cavernous sinus space can reliably be excluded.

Adenoma↗
PubMed2000

The effect of metformin on glycemic control, serum lipids and lipoproteins in diet alone and sulfonylurea-treated type 2 diabetic patients with sub-optimal metabolic control.

OBJECTIVE: To see if Metformin Monotherapy affects glycemic control, serum lipid or lipoprotein levels in the treatment of type 2 diabetes who were poorly controlled with diet alone or despite maximal doses of (sulfonylurea) oral glucose lowering agents. DESIGN: A prospective, clinical intervention trial conducted between 1996-1997. SETTING: Two out patient diabetic clinics of Karachi. PATIENTS AND METHODS: A 12-week prospective clinical intervention trial. A total of 30 type 2 diabetic subjects were enrolled, of Whom 21 (12 men and 9 women) completed the study period. Their ages ranged between 35 and 70 years, (mean +/- SD 53.3 +/- 9.31) years, with a mean duration since diagnosis of diabetes was 4.5 +/- 2.3 years, body mass index (mean +/- SD) 26.8 +/- 3.53 kg/m2. They were previously treated with diet alone or had already been taking maximum doses of sulfonylurea monotherapy with suboptimal glycemic control, i.e., raised fasting blood glucose concentrations of 6-15 mmol/L or (108-270 mg/dL) on two occasions, with significant hyperglycemic symptoms. The patients were treated with metformin monotherapy with a follow up of 12 weeks. The initial dosage was 500 mg twice daily, and the dosage was increased to two or three tablets depending on the patient's metabolic changes. By comparing before and after 12 weeks therapy with metformin we assessed the importance of baseline parameters (glycemic control, serum lipid and lipoprotein concentrations, and measures of change in body weight and body mass index). RESULTS: Metformin therapy significantly decreased fasting blood glucose levels in all patients [(mean +/- SD) 227.2 +/- 37.5 to 168.6 +/- 20.5 mg/dl, p < 0.001)]. Serum total cholesterol decreased marginally [(mean +/- SD) 200.3 +/- 18.7 to 181.4 +/- 19.4 mg/dl, p < 0.01)]. Serum total triglycerides concentration also decreased [(mean +/- SD) 195.9 +/- 31.9 to 174.2 +/- 26.6 mg/dl, P < 0.01)]. Low-density lipoproteins declined [(mean +/- SD) 123.5 +/- 16.9 to 105.5 +/- 19.1 mg/dl, P < 0.01)], and very-low density lipoprotein cholesterol also decreased [(mean +/- SD) 39.2 +/- 6.4 to 34.8 +/- to 5.3 mg/dl, P < 0.01)]. Whereas, high-density lipoprotein cholesterol tended to increase [(mean +/- SD) 37.7 +/- 5.1 to 39.5 +/- 4.9 mg/dl, P < 0.01)], while no significant changes occurred in body weight and body mass index. CONCLUSION: Metformin treatment was effective, safe, and generally well tolerated.

Adult↗
PubMed1999

[Tentorial meningioma. Surgical experience with 20 cases].

We report our experience and long-term results of twenty patients with tentorial meningiomas who underwent surgical removal between 1987 and 1996. Computed tomography, angiography and magnetic resonance imaging were used as diagnostic tools for planning the surgical procedure. The tumor site was posterolateral in 6 cases (30%), posteromedial in 4 cases (20%), in the tentorium itself in 4 cases (20%), anterolateral in 3 cases (15%), at the apex of tentorial incisura in 2 cases (10%) and at the free border of the tentorial notch in 1 case (5%). Neuroradiologically, 70% of the meningiomas ranged from 1 to 3 cm. Lateral and medial tumors with solely or mainly supratentorial development were approached from above. The approach from below was selected for meningiomas with subtentorial involvement only. In meningiomas with both supra and subtentorial growth, a supratentorial bone flap was combined with a suboccipital craniectomy using a retromastoid incision. Radical surgical removal (Simpson's grade I and II) was achieved in 80% of the cases. There was no mortality. The follow-up averaged 4 years and revealed that 65% of patients were able to return to their premorbid activity. Complications were mainly postoperative brain oedema, functional deficits, seizures and psychological disorders. Recurrence rate amounted at 6.25% in the group where the tumors were totally removed (16 cases). From this retrospective study, the statistically significant prediction of a good outcome was: duration of symptoms from onset to the operation inferior or equal to 1 year (p < 0.01), good preoperative neurological conditions (Karnofsky scale from 80 to 100) (p < 0.05) and tumor size inferior or equal to 3 cm (p < 0.002).

Adult↗
PubMed1999

The effects of glibenclamide on serum lipids and lipoproteins in type II non-insulin dependent diabetes mellitus.

OBJECTIVE: To examine the effects of glibenclamide treatment on plasma lipids and lipoprotein levels. SETTINGS: Out patients of Type II diabetics from department of Baqai Diabetes and Endocrine Centre and two other diabetic clinics of Karachi. METHODS: The effects of glibenclamide on blood glucose and various aspects of lipoproteins has been studied in 26 (14 male, 12 female) Type II Diapetes patients before and after 12 weeks of glibenclamide therapy. Treatment was initiated with 5 mg oral glibenclamide with diet control. The initial dosage of glibenclamide was 5 mg/day taken half an hour before meal; this was increased to 5 mg per week and was adjusted according to the patient's tolerance to the drug and their glycemic control. RESULTS: The results demonstrated that fasting blood glucose declined from 221.53 + 7.84 to 165.02 + 5.12 mg/dl, (P < 0.001). There was a statistically significant increase in the plasma high-density lipoprotein cholesterol from 33.60 + 1.00 to 37.07 + 1.05 mg/dl, (P << 0.05). Total cholesterol, triglycerides, low-density lipoprotein cholesterol and very-low-density lipoprotein cholesterol did not change significantly. CONCLUSION: Improved glycaemic control in patients treated with glibenclamide with Type II Diabetes was achieved which lead to changes in lipoprotein metabolism. There was no evidence of changes in lipoproteins in directions associated with an increased risk for atherosclerosis.

Blood Glucose↗
PubMed1999

[Hypophyseal surgical treatment of Cushing's disease in the child].

Cushing's disease in children is rare and not familar to pediatricians. We report here 7 cases concerning children between 8 and 16 years of age, treated by pituitary surgery with 1 to 9 year follow-up. A remission of hypercorticism was obtained in all cases. However, a pituitary deficiency requiring replacement opotherapy and/or a recurrence was observed in 5 out of 7 patients. From our experience and the review of literature (around 130 cases), Cushing's disease is more serious in children than in adult. We suggest therapeutic management with transsphenoidal surgery as the treatment of choice. Given the frequency of recurrence (13 à 54%) often late (9-12 years), we stress the need of regular and extended postoperative follow-up.

Adolescent↗
PubMed1998

Radiation-induced optic neuropathy 4 years after radiation: report of a case followed up with MRI.

We report a case of radiation-induced optic neuropathy in a 32-year-old man with Cushing's disease and a recurrent tumour of the left cavernous sinus. The patient experienced rapid, painless loss of vision 4 years after treatment without recurrence of tumour or other visual disorder. MRI showed enlargement and contrast enhancement of the optic chiasm. A year later the patient was almost blind and MRI showed atrophy and persistent contrast enhancement of the chiasm.

Adenoma↗