Search PubMed⌕ Search

Biomedical subjects

A Khalil

Publications and source records attributed to A Khalil.

At least 55 records · Page 3Linked to original sources
PubMed2000

Computed tomographic diagnosis of bronchogenic carcinoma in HIV-infected patients.

PURPOSE: To describe the features of bronchogenic carcinoma (BC) on plain radiography and computed tomography (CT) in human immunodeficiency virus (HIV)-infected patients; to evaluate percutaneous transthoracic needle biopsy (PTNB) in this setting; and to assess outcome. PATIENTS AND METHODS: We reviewed the medical charts, radiographs and chest CT scans in 15 AIDS patients with histologically proven BC. All but one of the patients were young men (mean age 48 years) with a long history of smoking (mean 40 pack-years). Adenocarcinoma was the predominant cell type (46.6%). The stage of the malignancy did not correlate with the CD4 cell count (mean 189 per mm(3)). The diagnosis was obtained by means of PTNB (n=7), bronchoscopy (n=4), thoracotomy (n=2), pleural biopsy (n=1) or extrathoracic biopsy (n=1). RESULTS: Parenchymal masses and nodules were the most common features (66.6%) on chest radiographs and CT. BC was peripheral in 11 cases (73%) and was located in the upper lobe in ten cases (66.6%). Enlarged lymph nodes were present in 60% of patients and metastases in 30%. PTNB was diagnostic in seven of the eight patients who underwent the procedure; complications included two pneumothoraces and one secondary implantation of tumor cells along the needle tract. Three lobectomies and one pneumonectomy were performed for stage I disease. The mean survival time among the patients who underwent surgery was 14 months. These survivals are more encouraging than some of those previously reported in the literature, furthermore, patients die of competing illnesses. CONCLUSION: BC in HIV-infected patients is similar to that in the general population. Early diagnosis can be achieved by means of PTNB. Surgical resection, when feasible, significantly improves survival.

Adult↗
PubMed2000

Renal cytokine responses in acute Escherichia coli pyelonephritis in IL-6-deficient mice.

The aim of this study was to investigate the influence of IL-6 on mortality, bacterial growth and cytokine expression in experimental acute pyelonephritis. Female IL-6-deficient mice and their wild-type counterparts, 8-10 weeks old, were infected with Escherichia coli CFT 073 or injected with NaCl 0.9% (w/v) via the urethra and thereafter obstructed for 6 h. Animals were killed at 48 h, 6 days or 8 weeks and cytokine and bacterial renal levels were assessed at each time point. We found that IL-6-deficient mice had increased mortality and extensive renal bacterial growth on day 6, compared with wild-type mice (P < 0.05) and the histopathological changes were generally more severe and widespread in the IL-6-deficient mice. Peak mRNA expression of IL-1beta, IL-4, IL-10, IL-12 and interferon-gamma (IFN-gamma) occurred 48 h after infection in both IL-6 knock out and wild-type mice. Transforming growth factor-beta (TGF-beta) levels also peaked at 48 h in E. coli-infected wild-type mice, while in the IL-6-deficient strain both TGF-beta mRNA and protein levels were significantly lower at 48 h than wild-type levels (P < 0.0008 and P < 0.03, respectively) and remained stationary throughout the study period. Animals injected with NaCl 0.9% (w/v) displayed a similar decrease in TGF-beta expression (P < 0.02). When splenocytes from the IL-6-deficient mice were incubated with murine recombinant IL-6, TGF-beta levels increased to those of wild-type mice. No increase was observed when splenocytes from wild-type mice were incubated with the same doses of rIL-6. We therefore conclude that IL-6 plays an important role in bacterial clearance and directly influences the TGF-beta levels in experimental acute pyelonephritis. We also demonstrate that urethral obstruction per se induces an increase in TGF-beta the magnitude of which is decreased in IL-6-deficient mice.

Animals↗
PubMed2000

Transient renal tubular acidosis in pregnancy.

Renal tubular acidosis in pregnancy is a very rare disorder. Most cases are either inherited or secondary to maternal disease or ingestion of toxic chemicals. We report a 22-year-old woman, previously healthy, who presented at 27 weeks of gestation with preterm labor. Investigation revealed renal tubular acidosis with no obvious etiology. Labor was stopped with various tocolytic drugs and her electrolyte imbalance was corrected. She was delivered at 36 weeks, by cesarean for a nonreassuring fetal heart tracing, of an appropriate-for-gestational-age infant weighing 2905 g. Evaluation 3 and 6 months postpartum revealed gradual, but complete resolution of the acidosis and electrolyte abnormality. The infant is now 7 months old, is growing normally with normal electrolytes, and with no evidence of acidosis.

Acidosis, Renal Tubular↗
PubMed2000

Pulmonary arteriovenous malformations.

OBJECTIVE: Helical CT scan (HCT), a noninvasive method, can detect pulmonary arteriovenous malformations (PAVMs). Its sensitivity is superior to that of global digitalized angiography, but patients receive a significant dose of radiation during diagnostic HCT. We compared HCT to contrast-enhanced pulmonary magnetic resonance angiography (CEMRA), a new noninvasive radiation-free method, in the diagnosis of PAVMs. PATIENTS AND METHODS: Five consecutive patients with PAVMs underwent HCT, CEMRA, and pulmonary artery digital subtraction angiography (PADSA). CEMRA was performed during the pulmonary arterial phase of an IV bolus of gadolinium. PADSA was performed during the embolization procedure. All images were examined for PAVMs. The site and size of aneurysms were specified, as well as the diameter of the vascular pedicles. RESULTS: Thirty PAVMs were detected by CEMRA and 38 by HCT. All 20 PAVMs at least 5 mm in diameter and 10 of the 18 PAVMs < 5 mm in diameter identified on HCT were also identified by CEMRA. Whatever the site, all PAVMs with a feeding artery diameter of at least 3 mm (ie, PAVMs with clinical consequences) were detected by CEMRA. No false-positive results were obtained with CEMRA. CEMRA therefore had a sensitivity of 78% and a specificity of 100%. CONCLUSIONS: CEMRA, a nonionizing and noninvasive procedure, has high sensitivity and specificity for the diagnosis of clinically relevant PAVMs.

Adult↗
PubMed2000

The placenta in meconium staining: lesions and early neonatal outcome.

PURPOSE: To evaluate the immediate neonatal outcome and the presence of various placental lesions in 96 pregnancies with meconium-stained amniotic fluid. MATERIALS AND METHODS: The patients were divided into a group with acute (N = 41) and subacute and chronic (N = 55) meconium staining of the placenta. Apgar scores, arterial cord pH and admission to the neonatal intensive care unit (NICU) were determined in addition to the findings on gross and microscopic examination of the placentas. RESULTS: Of the 53 live births with subacute and chronic meconium staining, 13% had Apgar Scores < or = 7 at 5 minutes compared to 7% with acute meconium staining. Similarly, a significantly lower umbilical artery pH was determined in the former group [(32%) versus (7%)], (p < 0.01). When 9 different pathologic lesions of the placenta were evaluated microscopically, the frequency of villous vascular thrombosis (25.4%), infarcts (38%), acute chorioamnionitis (20%), villous edema (9.1%) and villitis (14.5%) was significantly higher in the group with longer meconium exposure compared to the other group (2.4%), (9.7%), (7.3%), (0%), and 1 (2.4%), respectively. In addition, when tested for 4 different lesions, cases with acute meconium were less likely to have one or more lesions. When one or more placental lesions were found, NICU admission rate was significantly higher in the patients with subacute and chronic meconium. CONCLUSION: Subacute and chronic meconium discharge is associated with significant placental lesions and an increased risk of adverse pregnancy outcome in the immediate neonatal period.

Acidosis↗
PubMed2000

[Magnetic resonance angiography of the thorax in 2000].

Over the last five years, magnetic resonance imaging (MRI) has been the scene of explosive developments in many fields. MRI exploration of thoracic vessels, perfusion imaging of the pulmonary parenchyma, cine-MR, and apnea sequences have all seen impressive advances. This improvement has been made possible by progress in data processing and surface coil technology for a better signal-noise ratio. In 2000, indications for thoracic MRI remain limited due to the small number of machines available and the fact that the CT scan can provide superior quality images for the pulmonary parenchyma and for visualizing calcifications. MRI can be a complementary exam for lung cancer work-up in case of suspected invasion of the thoracic cavity or the mediastinum. It is the first intention exam in cases involving the greater vessels, with the exception of emergency situations, the posterior mediastinum, and the heart. We review here the current contribution of MRI in diseases of the chest and discuss perspectives for the future.

Humans↗
PubMed2000

Angiotensin II type 1 receptor antagonist (losartan) down-regulates transforming growth factor-beta in experimental acute pyelonephritis.

PURPOSE: To study the effect of an angiotensin II type 1 receptor antagonist, losartan, on cytokine expression, kidney growth and renal scarring in experimental acute pyelonephritis. MATERIALS AND METHODS: Female Bki NMRI mice, 8 weeks old were infected with E. coli CFT 073 via the urethra. Mice were divided into four groups; either left untreated; or treated with NaCl 0.9%; or an angiotensin II type 1 receptor antagonist, losartan, in doses of 1 mg. or 40 mg. /kg. body weight. The treatment was given daily i.p. for 48 hours, 3 weeks or 8 weeks respectively. Kidneys were weighed and sectioned for histo-pathology and in situ hybridization for mRNA of IL-1beta, TNF-alpha, IL-4, IL-6, IL-10, IL-12, TGF-beta and IFN-gamma. Homogenized kidneys were used for EIA of TGF-beta and bacterial growth. RESULTS: The mRNA expression of the studied cytokines generally peaked at 48 hours in all four groups. In animals treated with losartan, kidney TGF-beta, IFN-gamma and IL-6 decreased significantly at 3 and 8 weeks as compared with controls, untreated or those treated with NaCl, (p <0.005 respectively). Infection was associated with a declining kidney weight, also in the presence of losartan. A 50% reduction of the spread of renal scarring was observed in the losartan treated group, but this did however not reach significance. The proportion of kidneys showing bacterial growth was not influenced by losartan although in these kidneys the mean bacterial counts at 3 weeks were significantly higher in the losartan treated mice (p <0.006). CONCLUSIONS: Losartan is associated with downregulation of TGF-beta, IFN-gamma and IL-6 and may, in combination with antimicrobial therapy, reduce the risk of cortical renal scarring in recurrent acute pyelonephritis in infants.

Acute Disease↗
PubMed2000

[Spinal cord compression secondary to extramedullary hematopoiesis in a patient with thalassemia].

A 19-year-old man with homozygous beta thalassemia presented with signs of thoracic spinal cord compression secondary to extramedullary hematopoiesis. The patient was treated with hypertransfusion and hydroxyurea. After two months, clinical signs had resolved and magnetic resonance imaging showed significant regression of the extradural mass. Pathophysiology and therapeutic options in this condition are briefly discussed.

Adult↗
PubMed2000

[Orbital fracture with medial rectus entrapment. A case report].

Orbital fracture can be complicated by medial rectus muscle entrapment which usually involves the anterior part of the muscle (pseudo Duane syndrome). We describe an unusual case of isolated medial orbital wall fracture with medial rectus entrapment. Our patient had entrapment of the posterior part of the muscle with exotropia and limitation of adduction. This rare complication must be recognized so the appropriate management could be instituted early to avoid potential functional sequelae.

Child↗
PubMed2000

Plasmid-mediated catabolism of dicamba by Pseudomonas species strain PXM.

Pseudomonas species strain PXM, which is able to use dicamba (3,6-dichloro-2-methoxybenzoic acid; CAS 1918-00-9, Banvel) as its sole carbon source for growth, has been isolated. The catabolism of dicamba and some of its putative metabolic descendants correlates with the presence of a large and unstable plasmid.

Biodegradation, Environmental↗
PubMed2000

Age-related decrease of dehydroepiandrosterone concentrations in low density lipoproteins and its role in the susceptibility of low density lipoproteins to lipid peroxidation.

The incidence of atherosclerosis and related diseases increases with age. The aging process may enhance lipoprotein modification, which leads to an increase in the susceptibility of low density lipoprotein (LDL) and high density lipoprotein (HDL) to oxidation. Dehydroepiandrosterone (DHEA), the most abundant steroid hormone in humans, has been shown to have antiatherogenic effects. This hormone also decreases dramatically with age. In the present study, we were interested in determining the presence of DHEA/DHEAS (dehydroepiandrosterone sulfate) and changes in their concentrations in HDL and LDL lipoproteins with age. Moreover, we studied the susceptibility of LDL to oxidation with age in the presence or absence of vitamin E or DHEA. We demonstrated that vitamin E is unable to restore the decreased resistance to oxidation of LDL from elderly subjects to that of LDL obtained from young subjects. Furthermore, our results provide evidence that DHEA is an integral part of LDL and HDL and disappears to almost nondetectable levels during aging. The DHEA incorporated into the LDL from elderly subjects increased LDL resistance to oxidation in a concentration-dependent manner. The increased resistance provided by DHEA was higher than that with vitamin E. DHEA seems to act either by protecting vitamin E from disappearance from LDL under oxidation or by scavenging directly the free radicals produced during the oxidative process. Our results suggests that DHEA exerts an antioxidative effect on LDL, which could have antiatherogenic consequences. Careful clinical trials of DHEA replacement should determine whether this ex vivo effect could be translated into any measurable antiatherogenic (cardioprotective) action.

Adult↗
PubMed1999

Tamoxifen and endometrial pathologies: a prospective study.

OBJECTIVE: The purpose of this study was to prospectively follow a group of women with breast cancer, on tamoxifen, for the development of endometrial pathologies. MATERIALS AND METHODS: Eighty women with breast cancer, on tamoxifen, were prospectively followed every 6 months with pelvic examination, Pap smear, vaginal ultrasound, and endometrial biopsy. RESULTS: Nine women were lost to follow-up prior to initiation of treatment and 4 refused biopsies, leaving 67 patients for evaluation. Fifty (74.6%) of the 67 patients were already on tamoxifen for a mean duration of 15.8 +/- 16.6 months and had a baseline benign, unremarkable endometrium at the time of entry into the study. The total duration of treatment was 32.5 +/- 19.6 months (median 30 months). The mean age of the patients was 51.7 +/- 9.9 years (median 52 years). Of the patients, 56.7% were postmenopausal. Sixty-three patients had a benign endometrium (mean age 51.8 +/- 10.1 years, mean duration 33.1 +/- 19.6 months). Two patients had simple hyperplasia (mean age 43.5 years, duration 28.5 +/- 33.2 months), 1 patient had complex hyperplasia with atypia (age 57 years, duration 13 months), and another patient developed adenocarcinoma (grade 3) after 22 months. These 4 patients had abnormal vaginal bleeding. Seven patients developed endometrial polyps (mean age 54.0 +/- 8.5 years, duration 36 +/- 24.2 months). The mean endometrial thickness for patients with histologically unremarkable and abnormal endometrium was not significantly different (7.6 +/- 3.9 vs 8.8 +/- 5.0 mm, respectively) (median 7.0 mm for both groups). No endometrial thickness cutoff point reached statistical significance. The patient who developed endometrial cancer had a thickness of only 3 mm. CONCLUSION: All patients who developed an abnormal endometrium had abnormal vaginal bleeding. There was no correlation between endometrial thickness and endometrial pathology; thus the value of routine screening remains controversial.

Adult↗
PubMed1999

Utility of CT scan for the diagnosis of chest wall tuberculosis.

The objective of this study was to determine the utility of CT scan findings for the diagnosis of chest wall tuberculosis, excluding the spine. We reviewed 15 patients (13 Africans and 2 Indians) with chest wall tuberculosis, retrospectively. The radiologic examination consisted of a plain X-ray and a CT scan of the chest for each patient. The site of disease was the rib in 13 patients or the body of the sternum in 2 patients. One rib was involved in 11 patients, 2 contiguous ribs (one site) in 2 patients, and bilateral disease (two sites) was observed in the remaining patient. The 14 rib sites involved the posterior arc or costovertebral joint in 11 cases, the anterior arc in 2 cases, and the anterior and middle arc in 1 case. The CT scan findings were an abscess (n = 14) or a soft tissue mass (n = 2), osteolytic lesions (n = 13), periosteal reaction (n = 10), and sequestrum (n = 14). Bone sclerosis was observed only in 3 cases of rib involvement. The association of a soft tissue abscess, an osteolytic lesion, and sequestrum, especially in immigrants to France, suggests chest wall tuberculosis on CT scan.

Adult↗
PubMed1999

Effects of gliclazide versus metformin on the clinical profile and lipid peroxidation markers in type 2 diabetes.

The sulfonylurea gliclazide and the biguanide metformin have different mechanisms to reduce glycemia. We performed a randomized study to compare these two agents with respect to glycemic control and effects on lipid peroxidation markers in 36 adult patients with type 2 diabetes. Both agents significantly decreased glycosylated hemoglobin ([HbA1c] P < .05), fructosamine (P < .05), and the glucose-excursion curve during the oral glucose tolerance test ([OGTT] P < .01). With regard to the insulin curve during this test, no significant change was observed with metformin and a significant increase was measured with gliclazide (P < .05). Considering the small number of events, no significant difference was detected in the number of hypoglycemic episodes between the two agents. More upper-gastrointestinal (GI) symptoms were observed with metformin compared with gliclazide (P < .05). Even with no change in the standard lipid profile, both agents increased serum vitamin E (P < .01 for gliclazide and P < .05 for metformin) and decreased the level of lipid peroxidation markers in low-density lipoprotein (LDL) and high-density lipoprotein (HDL) particles (P < .05). Despite different mechanisms of action, gliclazide and metformin demonstrated comparable levels of efficacy and complementary effects on lipid peroxidation markers.

Aged↗
PubMed1999

Ocular toxicity in low-dose tamoxifen: a prospective study.

PURPOSE: To look at the incidence, symptomatology, course and reversibility of low-dose tamoxifen ocular toxicity. METHODS: Sixty-five women with breast cancer, on tamoxifen oral therapy (20 mg/day), and a totally normal eye examination, were prospectively followed up. A full ophthalmic evaluation was done every 6 months, for a median of 30 months (range 4-79 months). Any sign of toxicity in the cornea, lens, retina or optic nerve was looked for, whether associated with a change in visual acuity or not. RESULTS: Ocular toxicity was documented in 8 patients, giving an incidence of 12%. Seven patients had keratopathy in the form of subepithelial deposits, whorls and linear opacities. Three of these patients had a concurrent symptomatic bilateral pigmentary retinopathy that warranted discontinuation of therapy. One patient developed bilateral optic neuritis that left her with optic nerve pallor and a decrease in vision. The patients who had the toxicity had a significantly higher tamoxifen cumulative dose (p = 0.03), and were longer on treatment (p = 0.04), than the non-affected ones. The keratopathy changes were reversible upon discontinuation of the drug. CONCLUSION: Prompt reporting of symptoms and yearly ophthalmic examinations are mandatory in patients on tamoxifen to detect toxic effects while these are still reversible.

Adult↗