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M Mansour

Publications and source records attributed to M Mansour.

At least 19 recordsLinked to original sources
PubMed2005

Estrogen-induced abnormal accumulation of fat cells in the rat penis and associated loss of fertility depends upon estrogen exposure during critical period of penile development.

We previously reported that diethylstilbestrol (DES) or estradiol valerate (EV) exposure at a dose of 0.10-0.12 mg/kg, or higher, per day, on alternate days, from postnatal days 2-12, resulted in abnormal penis development and infertility (H. O. Goyal et al., 2005, J. Androl. 26, 32-43). The objective of this study was to identify a critical developmental period(s) during which EV exposure results in the observed penile abnormalities. Male pups received EV at a dose of 0.10-0.12 mg/kg on postnatal day(s) 1, 1-3, 4-6, 1-6, 7-12, 13-18, 19-24, or 25-30. Fertility was tested at 102-115 days of age and tissues were examined at 117-137 days. Both penile morphology and fertility were unaltered in rats treated with EV after 12 days of age. Conversely, except in rats treated on postnatal day 1 only, none of the males treated prior to 12 days of age sired pups, and all had abnormal penises, including varying degrees of abnormal accumulation of fat cells and loss of cavernous spaces and smooth muscle cells in the corpora cavernosa penis, which were maximal in the 1-6-day group. Also, the preputial sheath was partially released or its release was delayed, and the weight of the bulbospongiosus muscle was significantly reduced. Plasma testosterone (T) in the 1-6- and 4-6-day groups and intratesticular T in the 4-6-day group were significantly lower. The testosterone surge, characteristic of controls in the first week of life, was suppressed in the 1-3-day group. Estrogen receptor alpha mRNA expression was enhanced in the body of the penis in the 1-3-day group, but not in the 13-18-day group. Hence, EV exposure prior to 12 days of age (as short as 1-3 days postnatal), but not after 12 days of age, results in long-term abnormal penile morphology, characterized by abnormal accumulation of fat cells in the corpora cavernosa penis and, consequently, loss of fertility.

Adipocytes↗
PubMed2005

Early acute rejection episodes in renal transplantation in relation to immunosuppression protocols: an audit of 100 cases.

INTRODUCTION: Early acute rejection episodes (ARE) have deleterious effects on graft outcomes. The incidence of ARE in the first 3 months has been reported to be <20%. In a recent audit of ARE among 100 renal transplants, we observed the rates to be high (30%). We retrospectively collected details of donor type, induction therapy, immunosuppression medications, drug levels, HLA mismatches, acute tubular necrosis (ATN), and delayed graft function (DGF) to correlate with ARE and response to therapy. RESULTS: Thirty rejection episodes occurred after a mean period of 14.3 days after transplantation. Ninety-one patients had induction treatment with either antithymocyte globulin (ATG) or interleukin 2 receptor antibodies (IL2 Rab). The drugs included cyclosporine, mycophenolate, sirolimus, azathioprine, and prednisolone in these patients. There was no significant difference in ARE among the different drug protocols (30.7%-35.2%). Subjects with 4 or more HLA mismatches displayed more ARE (40.3%) compared with those with 3 or less (23%). Subjects with ATN or DGF immediately posttransplantation had a higher incidence of ARE (39.2%) than those without them (26.3%). Deceased donor recipients had a higher episode of ARE (45.1%) compared with live related donor recipients (25%). On stratifying the known risk factors for ARE, subjects with no risk factors had the least (22.2%) ARE compared with those with one (32.5%) or two (47.6%) risk factors. Subjects who failed to achieve adequate cyclosporine (C2) levels showed significantly higher rates of ARE (86.9%) than those with adequate or higher levels (8.6%). CONCLUSION: Higher HLA mismatches, DGF, deceased donor, and failure to achieve adequate cyclosporine levels were observed to be major risk factors for the development of ARE.

Acute Disease↗
PubMed2005

The area under the concentration-time curve versus trough and peak blood level monitoring in renal transplant recipients on cyclosporine.

OBJECTIVE: The area under the concentration-time curve of cyclosporine microemulsion is the best measure of the absorption and beneficial effects in renal transplant recipients. We sought to determine the best method of monitoring cyclosporine levels in these patients. METHODS: Prospective evaluation of peak cyclosporine blood levels and area under the curve monitoring were performed for 1 year in 65 renal transplant recipients (study group). Cyclosporine trough levels and peak cyclosporine blood levels were correlated with the calculated area under the curve. Cyclosporine trough levels were monitored in equal numbers of matched controls. RESULTS: There were no significant differences in the incidence of acute rejection, cyclosporine nephrotoxicity, proteinuria, serum creatinine levels, or graft and patient outcomes between the groups (P = .1). Peak cyclosporine blood levels guided by calculating the area under the curve were found to be 27% to 32% lower than previously reported. The correlation coefficient was <70% for cyclosporine trough levels (P < .02) and >90% for peak cyclosporine blood levels (P < .001) when related to the calculated area under the curve. The calculated area under the curve was approximately 6000 ng/mL/h following transplantation, gradually decreasing to approximately 3000 ng/mL/h at 1 year. Both appeared to the acceptable therapeutic values. CONCLUSION: Calculating the area under the curve using trough and peak blood levels versus using isolated readings for either of these levels alone is the most effective method of monitoring cyclosporine in recipients undergoing renal transplant.

Adolescent↗
PubMed2005

Results in 158 consecutive cadaveric renal transplantations.

OBJECTIVES: We investigated the outcome of deceased donor kidney transplantations performed in a single center in a developing country. MATERIALS AND METHODS: A total of 158 patients (69 male and 89 female patients, including 32 children) received kidney grafts obtained from deceased donors between March 1996 and October 2004. Cadaveric renal grafts were transplanted after a cold ischemia time of 4 to 24 hours (mean, 12.5 hours). Retransplantation was performed in 19 recipients. Induction immunosuppression was achieved with antithymocyte globulin. The diagnosis of acute graft rejection was based on histopathological findings. RESULTS: Primary graft function was observed in 77% of cases. Posttransplantation complications were: surgical (n = 60; 38%), systemic bacterial and viral infections (n = 33; 21%), acute rejection (n = 47; 30%), and malignancy (n = 2; 1.3%). Seventeen recipients died with a functioning graft, and 23 more grafts were lost. The 7-year actuarial survival rates were 89% and 75% for recipients and grafts, respectively. CONCLUSIONS: The kidney transplantation program in Kuwait is steadily growing. Kidney grafts obtained from deceased donors contributed 28% of the transplantation activity and were associated with a high rate of primary function. Overall actuarial recipient and graft survival rates were comparable to those reported by larger centers.

Adolescent↗
PubMed2005

[Ectopic pregnancy with etonogestrel contraceptive implant (Implanon): first case].

We describe the first case of ectopic pregnancy occurring in a patient with an etonogestrel contraceptive implant (Implanon). There was no factor predisposing to a failure of the technique (implant in place for less than 2 years and normal BMI). In addition there was no risk factor for an ectopic location of the pregnancy. We discuss the role of the micro progestative in the location of the pregnancy. This case report emphasizes the fact that ectopic pregnancy should not be ruled out in women taking this contraception, however efficient it is otherwise.

Contraceptive Agents, Female↗
PubMed2004

Abnormal morphology of the penis in male rats exposed neonatally to diethylstilbestrol is associated with altered profile of estrogen receptor-alpha protein, but not of androgen receptor protein: a developmental and immunocytochemical study.

Objectives of the study were to determine developmental changes in morphology and expression of androgen receptor (AR) and estrogen receptor (ER)alpha in the body of the rat penis exposed neonatally to diethylstilbestrol (DES). Male pups received DES at a dose of 10 microg per rat on alternate days from Postnatal Day 2 to Postnatal Day 12. Controls received olive oil vehicle only. Tissue samples were collected on Days 18 (prepuberty), 41 (puberty), and 120 (adult) of age. DES-induced abnormalities were evident at 18 days of age and included smaller, lighter, and thinner penis, loss of cavernous spaces and associated smooth muscle cells, and increased deposition of fat cells in the corpora cavernosa penis. Fat cells virtually filled the entire area of the corpora cavernosa at puberty and adulthood. Plasma testosterone (T) was reduced to an undetectable level, while LH was unaltered in all treated groups. AR-positive cells were ubiquitous and their profile (incidence and staining intensity) did not differ between control and treated rats of the respective age groups. Conversely, ERalpha-positive cells were limited to the stroma of corpus spongiosus in all age groups of both control and treated rats, but the expression in treated rats at 18 days was up-regulated in stromal cells of corpora cavernosa, coincident with the presence of morphological abnormalities. Hence, this study reports for the first time DES-induced developmental, morphological abnormalities in the body of the penis and suggests that these abnormalities may have resulted from decreased T and/or overexpression of ERalpha.

Aging↗
PubMed2004

[Prevalence of renal artery stenosis in patients undergoing cardiac catheterization: when should abdominal aortography be performed? Results in 467 patients].

PURPOSE: To define a subgroup of patients at increased risk of renal artery stenosis (RAS) in a population of patients undergoing cardiac catheterization. MATERIALS AND METHODS: A total of 467 patients (mean age of 64 Years +/-11) underwent cardiac catheterization and aortography Results were evaluated to detect correlations between the presence or absence of RAS and clinical and biological parameters. RESULTS: A total of 42 (9%) patients had a renal artery stenosis. Univariate analysis defined parameters correlated with the presence of RAS: systolic blood pressure (p=0.03), pulse pressure (p=0.005), age (p<0.0001), creatinine clearance (p<0.0001), 2-vessel (p=0.028) and 3-vessel (p=0.037) coronary artery diseases. Multivariate analysis showed that the presence of RAS correlated to creatinine clearance (p=0.02) and 2-vessel coronary artery disease. A creatinine clearance between 30 and 60 ml/min and multi-vessel coronary artery disease defined a subgroup at increased risk of RAS with sensitivity, specificity, positive and negative predictive values of: 47.6, 90.1, 32.3 and 94.6%. The prevalence of renal artery stenosis was 5.2% when both parameters were absent. CONCLUSION: Patients with mild renal insufficiency and multi-vessel coronary artery disease defined a subgroup of patients at increased risk of RAS (32.5%) that may benefit from abdominal aortography performed at the time of cardiac catheterization.

Aged↗
PubMed2004

Hemodialysis for patients bleeding or at risk for bleeding, can be simple, safe and efficient.

AIM: Hemodialysis for patients bleeding or at risk for bleeding requires special modalities of treatment that are difficult to perform without potential side effects. A simple, safe and adequate method may be applied. METHODS: A modified way of extracorporeal circuit preparation, which focuses on minimizing the blood-air interface and negligible saline flushing of 50 ml/h, is applied for a maximum of 3-hour session with routine (not one-to-one) nursing attendance. Data from 16,954 sessions performed with patients bleeding or at risk for bleeding (15,730 retrospectively and 1,224 prospectively collected) were analyzed. RESULTS: Cumulative failure of treatment, as defined by clotting of the extracorporeal circuit requiring termination of the procedure or replacement of the clotted part, was not more than 5% as expected for anticoagulation-free hemodialysis. For the prospectively recorded sessions, blood flow was 234 +/- 30 ml/min with less than 250 ml/min in 42.4% of the sessions. Native blood access was used in 426 (34.8%), double-lumen catheter in 798 (65.2%), 42 were isolated ultrafiltration sessions and 64 blood, 21 plasma, 9 platelet units were transfused. Post/pre urea ratio was 0.50 +/- 0.12. Logistic regression showed that among the following: duration of the session, type of dialysis, ultrafiltration rate, hematocrit, number of platelets, serum total protein, transfusions, blood flow and type of access, only blood flow significantly affected failure incidence (coefficient B = -0.041, exp(B) = 0.96, p = 0.04). No complications due to treatment were noted. CONCLUSION: In patients with active, or at risk for, bleeding, hemodialysis without systemic anticoagulation can be adequately and safely performed almost as a routine session.

Adolescent↗
PubMed2003

Ultrasound biomicroscopic evaluation of the traumatized eyes.

PURPOSE: To review causes for performing an ultrasound biomicroscopic (UBM) examination in traumatized eyes, to present common UBM findings of 109 eyes with a history of ocular trauma and to compare these findings according to the type of the trauma. MATERIALS AND METHODS: A total of 109 eyes with a history of mechanical ocular trauma, which underwent an UBM examination between December 1996 and April 2002, were evaluated retrospectively. All cases were classified according to the criteria of the Ocular Trauma Classification Group and UBM findings were reviewed. For statistical ana- lyses, chi(2) test and Fisher's exact test were used. RESULTS: UBM examinations were performed for the evaluation of the zonules before cataract surgery (49.5%), examination of the anterior segment in the presence of media opacities (32.1%), detection of suspected ocular foreign bodies (10.1%) and the evaluation of ocular hypotony (8.3%). In all, 67 eyes (61.5%) had a closed-globe injury, whereas 42 (38.5%) had an open-globe injury. The most common UBM findings in a closed-globe injury were zonular deficiency (64.2%), angle recession (43.3%), iridodialysis (17.9%), and dislocated lens (16.4%). The most common UBM findings in an open-globe injury were zonular deficiency (54.8%), iridodialysis (26.2%), peripheral anterior synechiae (PAS) (26.2%), and iridocorneal adhesion (19%). Among the common UBM findings, the angle recession was significantly higher (P<0.001) in closed-globe injury group and PAS formation was significantly higher (P<0.05) in open-globe injury group. CONCLUSIONS: UBM is particularly superior to other methods in the evaluation of the zonular status, angle recession, cyclodialysis, and the detection of small superficial and intraocular foreign bodies.

Adolescent↗
PubMed2002

Maximum intensity projection analysis in magnetic resonance of the breast.

The aim of this study was to determine the sensitivity, specificity and accuracy of vascular asymmetries and vessel location seen using MR Maximum Intensity Projection imaging for malignant and benign lesions. We enrolled 101 women, with an age ranging from 29 to 69 years (mean age of 53.1 years), with a mammary nodule and candidate for surgical intervention. MR was carried out using a 1.5 Tesla superconductive magnet, equipped with a double and bilateral Phased Array dedicated coil. All images obtained were processed using MIP. The relationship between an asymmetry due to a greater amount of vascular structures in the breast with a malignant neoplasm and symmetry with benign neoplasms were statistically significant (p < 0.001): sensitivity of 71.8%, specificity 100% and accuracy 76.2%. The relationship between perilesional or intralesional vessels with malignant versus benign neoplasms were statistically significant (p < 0.001): sensitivity 88.5%, specificity 82.6% and accuracy 87.1%. We concluded that asymmetries between breasts and the presence of perilesional or intralesional vessels seen in MIP images are important signs and, therefore, must be reported.

Adult↗
PubMed2001

Heteromeric AMPA receptors assemble with a preferred subunit stoichiometry and spatial arrangement.

AMPA receptors are thought to be a tetrameric assembly of the subunits GluR1-4. We have examined whether two coexpressed subunits (GluR1/2) combine at random to form channels, or preferentially assemble with a specific stoichiometry and spatial configuration. The subunits carried markers controlling ion permeation and desensitization, and these properties were monitored as a function of relative expression level and subunit composition. Homomeric receptors assembled stochastically while heteromeric receptors preferentially formed with a stoichiometry of two GluR1 and two GluR2 subunits, and with identical subunits positioned on opposite sides of the channel pore. This structure will predominate if GluR1 binds to GluR2 more rapidly during receptor assembly than other subunit combinations. The practical outcome of selective heteromeric assembly is a more homogenous receptor population in vivo.

Cell Line↗
PubMed2001

Left-to-right gradient of atrial frequencies during acute atrial fibrillation in the isolated sheep heart.

BACKGROUND: Recent studies demonstrated spatiotemporal organization in atrial fibrillation (AF). We hypothesized that waves emanating from sources in the left atrium (LA) undergo fragmentation, resulting in left-to-right frequency gradient. Our objective was to characterize impulse propagation across Bachmann's bundle (BB) and the inferoposterior pathway (IPP) during AF. METHODS AND RESULTS: In 13 Langendorff-perfused sheep hearts, AF was induced in the presence of acetylcholine (ACh). Fast Fourier transform of optical and bipolar electrode recordings was performed. Frequency-dependent changes in the left-to-right dominant frequency (DF) gradient were studied by perfusing D600 (2 micromol/L) and by increasing ACh concentration from 0.2 to 0.5 micromol/L. BB and IPP were subsequently ablated. At baseline, a left-to-right decrease in DFs occurred along BB and IPP, resulting in an LA-right atrium (RA) frequency gradient of 5.7+/-1.4 HZ: Left-to-right impulse propagation was present in 81+/-5% and 80+/-10% of cases along BB and IPP, respectively. D600 decreased the highest LA frequency from 19.7+/-4.4 to 16.2+/-3.9 Hz (P<0.01) and raised RA DF from 8.6+/-2.0 to 10.7+/-1.8 Hz (P<0.05). An increase in ACh concentration increased the LA-RA frequency gradient from 4.9+/-1.8 to 8.9+/-1.8 Hz (P<0.05). Ablation of BB and IPP decreased RA DF from 10.9+/-1.2 to 9.0+/-1.5 Hz (P<0.01) without affecting LA DF (16.8+/-1.5 versus 16.9+/-1.8 Hz, P=NS). CONCLUSIONS: Left-to-right impulse propagation and frequency-dependent changes in the LA-RA frequency gradient during AF strongly support the hypothesis that this arrhythmia is the result of high-frequency periodic sources in the LA, with fibrillatory conduction away from such sources.

Acetylcholine↗
PubMed2001

Complexins regulate a late step in Ca2+-dependent neurotransmitter release.

Synaptic vesicle fusion at synapses is triggered by increases in cytosolic Ca2+ levels. However, the identity of the Ca2+ sensor and the transduction mechanism of the Ca2+ trigger are unknown. We show that Complexins, stoichiometric components of the exocytotic core complex, are important regulators of transmitter release at a step immediately preceding vesicle fusion. Neurons lacking Complexins show a dramatically reduced transmitter release efficiency due to decreased Ca2+ sensitivity of the synaptic secretion process. Analyses of mutant neurons demonstrate that Complexins are acting at or following the Ca2+-triggering step of fast synchronous transmitter release by regulating the exocytotic Ca2+ sensor, its interaction with the core complex fusion machinery, or the efficiency of the fusion apparatus itself.

Adaptor Proteins, Vesicular Transport↗
PubMed2001

Application of coupled liquid chromatography-mass spectrometry in photolysis studies of the herbicide triflusulfuron-methyl.

The photochemical fate of the herbicide triflusulfuron-methyl in aqueous solution under UV light (lambda > 290 nm) was investigated. Nine photoproducts were detected and tentatively identified by LC/MS and LC/MS/MS analysis. The main routes of degradation involve the cleavage and/or contraction of the sulfonylurea bridge with the elimination of sulfur dioxide, which increases the acidity of the reaction medium. On the basis of the results obtained a photodegradation pathway is proposed.

Benzoates↗
PubMed2001

A side-by-side comparison of sampling methods for settled, indoor allergens.

Exposure to indoor allergens is associated with asthma, but there is no standardized sampling method for measuring allergens. We compared the association of measured allergen exposure and serum-specific IgE levels and the precision of three sampling methods (Cyclone, Mighty Mite, and Readivac II) to identify a standardized sampling method for indoor allergens. A random sample of 72 children, 5 to 17 years old, with doctor-diagnosed asthma who lived in the same residence >or=2 years were enrolled. Composite, side by side floor samples were obtained with all three methods. Dust allergen concentrations and serum-specific IgE levels were measured for Der f I, Fel d I, and Bla g I. Mean allergen concentration did not differ significantly by sampling method. Cat allergen was significantly correlated with serum-specific IgE for Cyclone (P=0.003) and Mighty Mite (P=0.008), but only marginally for Readivac II (P=0.07). Dust mite allergen was significantly correlated with serum-specific IgE for Readivac II (P=0.02) and Cyclone (P=0.038), but not for Mighty Mite (P=0.12). Cockroach allergen was not correlated with serum-specific IgE for any sampling method. In multiple linear regression, cat allergen was associated with serum-specific IgE for Cyclone (P=0.007) and Mighty Mite (P=0.02), but not for Readivac II (P=0.06). In contrast, dust mite allergen was marginally associated with serum-specific IgE for Readivac II (P=0.07), but not for Mighty Mite (P=0.64) or Cyclone (P=0.27). The Cyclone and Mighty Mite were more precise than Readivac II for cat allergen, but there was no difference for dust mite allergen (P>0.05). No single method is superior for measurement of indoor allergens. In general, cat allergen collected with the Cyclone was a better predictor of serum-specific IgE levels to Fel d I, whereas dust mite allergen collected with the Readivac II was a better predictor of serum-specific IgE levels to Der f I.

Adolescent↗
PubMed2001

Neural networks studies: quantitative structure-activity relationships of antifungal 1.

Models of relationships between structure and antifungal activity of 1-[2-(substituted phenyl)allyl]imidazoles and related compounds were constructed by means of a multilayer neural network using the back-propagation (BP) algorithm. Each molecule was described by three structural and one physicochemical parameters. The leave-one-out procedure was used to assess the predictive ability of a neural network model. The results obtained were compared to those given in the literature by the multiple linear regression (MLR), and were found to be better. The contribution of each descriptor to the structure-activity relationships was evaluated. Hydrophobicity of the molecule was confirmed to take the most relevant part in the molecular description.

Antifungal Agents↗
PubMed2001

Uveal effusion after cataract surgery: an echographic study.

PURPOSE: To determine the incidence of uveal effusion after cataract surgery and to relate its presence to selected preoperative, intraoperative, and postoperative variables. DESIGN: Prospective consecutive observational case series. PARTICIPANTS: Two hundred seven eyes of 205 subjects undergoing cataract surgery. METHODS: Several preoperative, intraoperative, and postoperative variables of potential significance in uveal effusion after cataract surgery were studied. On the first postoperative day and within 2 weeks after the surgery, subjects were examined clinically and echographically with B-scan for evidence of suprachoroidal (uveal) effusion. When effusion was present, follow-up examinations were performed until complete resolution was documented. MAIN OUTCOME MEASURES: Echographic presence of uveal effusion in the postoperative period. RESULTS: Uveal effusion was documented echographically in 12 patients (5.8%). Only one of these cases was clinically evident. All effusions were small and resolved with no intervention. The presence of postoperative hypotony related to wound leak (intraocular pressure <10 mmHg) was significantly correlated with uveal effusion after cataract surgery (P<0.0001). The combination of oral acetazolamide and topical pilocarpine gel given after the surgery also correlated with effusion (P<0.02). Intraoperative complications and prolonged phacoemulsification time were not shown to be risk factors for effusion. CONCLUSIONS: Uveal effusion is rarely seen after modern, small-incision, closed-system cataract surgery. It is correlated with postoperative hypotony related to wound leak and with the administration of both oral acetazolamide and topical pilocarpine after surgery.

Acetazolamide↗