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Biomedical subjects

H Nahum

Publications and source records attributed to H Nahum.

At least 19 recordsLinked to original sources
PubMed2001

Timing of testicular sperm retrieval procedures and in vitro fertilization-intracytoplasmic sperm injection outcome.

OBJECTIVE: To compare the outcome of IVF-intracytoplasmic sperm injection (ICSI) using testicular spermatozoa obtained on the day of ovum pick-up (OPU) or on the day before OPU. DESIGN: Retrospective study. SETTING: An IVF clinic in a university hospital. PATIENT(S): Forty-seven IVF-ICSI cycles using testicular spermatozoa in 28 couples with the male partner suffering from nonobstructive azoospermia. INTERVENTION(S): Sperm retrieval was performed either on the OPU day (23 cycles in 19 patients; group A) or on the day before OPU (24 cycles in 15 patients; group B). Testicular sperm aspiration (TESA) was performed and followed by testicular sperm extraction (TESE) if no spermatozoa could be found. MAIN OUTCOME MEASURE(S): The presence of motile spermatozoa at the time of ICSI and fertilization and clinical pregnancy rates. RESULT(S): A similar proportion of motile spermatozoa (60.9% vs. 62.5%), fertilization rate (61.7% vs. 58.9%), and clinical pregnancy rate per transfer (34.8% and 29.2%) were obtained for groups A and B, respectively. CONCLUSION(S): Testicular sperm retrieval can be performed on the day before OPU without compromising success. Considerable medical and practical advantages may be offered by further advancement of testicular sperm retrieval procedures to 48 hours before OPU. This approach should thus be further evaluated.

Adult↗
PubMed2000

Zygote intrafallopian transfer in patients with tubal factor infertility after repeated failure of implantation with in vitro fertilization-embryo transfer.

OBJECTIVE: To evaluate the efficacy of zygote intrafallopian transfer (ZIFT) in terms of implantation and pregnancy rates in patients with tubal factor infertility and repeated implantation failure in IVF-ET cycles. DESIGN: Retrospective analysis of ZIFT cycles. SETTING: An IVF unit in a university hospital. PATIENT(S): Criteria for patient selection for ZIFT included at least four failures of implantation in IVF-ET cycles in which at least 3 embryos were replaced per transfer and a cause of infertility diagnosed as male, unexplained, or tubal factor with proof of one patient tube. INTERVENTION(S): Four to six zygotes were transferred by laparoscopy into the fallopian tube 24-26 hours after oocyte retrieval. MAIN OUTCOME MEASURE(S): Implantation and pregnancy rates were determined in 112 ZIFT cycles performed in 81 patients with repeated failure of implantation. Results were further stratified for patients with tubal factor (n = 15) and patients without tubal factor (n = 66). RESULT(S): The pregnancy and implantation rates for all ZIFT cycles were 35.1% and 11.1%, respectively. Pregnancy and implantation rates per cycle in patients with tubal factor versus patients without tubal factor were 26.6% versus 37.1% and 9.4% versus 11.4%, respectively. CONCLUSION(S): ZIFT can be considered as a mode of treatment for patients with repeated failure of implantation in IVF-ET and with tubal factor with proved patency of one tube.

Embryo Implantation↗
PubMed2000

Poor outcome with round spermatid injection in azoospermic patients with maturation arrest.

OBJECTIVE: To compare the outcome of intracytoplasmic sperm injection (ICSI) and round spermatid injection (ROSI), both obtained by testicular sperm extraction (TESE), and to compare the results of fresh versus frozen ROSI. DESIGN: Retrospective study. SETTING: An IVF unit at a university hospitalPatient(s): Eighteen infertile couples with nonobstructive azoospermia. INTERVENTION(S): TESE with ROSI or ICSI of mature spermatozoa into metaphase II oocytes was performed. The resulting embryos were transferred to female partners. The spare round spermatids were frozen. MAIN OUTCOME MEASURE(S): Fertilization and cleavage rates, embryo quality, and clinical pregnancy rates. RESULT(S): Seventeen ROSI cycles and six ICSI cycles were compared. Fertilization rate following ROSI (44.9%) was significantly lower than with ICSI (69%). A significantly higher rate of cleavage arrest occurred following ROSI (40.8%) as compared to ICSI (8.2%). The morphology of embryos resulting from ROSI was significantly poorer. No pregnancies were achieved following ROSI as compared to a 50% clinical pregnancy rate in the ICSI group. The fertilization and cleavage rates following ROSI with fresh versus frozen-thawed spermatids were comparable. CONCLUSION(S): In azoospermic patients with maturation arrest at the stage of round spermatids the efficiency of ROSI appears to be extremely poor. The role of ROSI in the treatment of nonobstructive azoospermia should be reevaluated.

Adult↗
PubMed2000

Estradiol supplementation during the luteal phase may improve the pregnancy rate in patients undergoing in vitro fertilization-embryo transfer cycles.

OBJECTIVE: To evaluate the effect of adding E(2) to progestin supplementation during the luteal phase on pregnancy and implantation rates in patients undergoing IVF cycles. DESIGN: Prospective, randomized study. SETTING: An IVF unit in a university hospital. PATIENT(S): Patients who were undergoing IVF with controlled ovarian hyperstimulation using a GnRH analog and who had E(2)2,500 pg/dL at the time of hCG administration. INTERVENTION(S): Serum concentrations of E(2) and progesterone were measured in all patients on days 7, 10, and 12 after ET. MAIN OUTCOME MEASURE(S): The E(2) and progesterone profiles of the luteal phase and the pregnancy and implantation rates were documented. Data were analyzed for the entire study population and further stratified according to the GnRH analog protocol used (short or long). RESULT(S): Significantly higher E(2) levels were found during the luteal phase in the group that received E(2) supplementation. This effect was more pronounced in the patients who were treated with the long GnRH analog protocol. Significantly higher pregnancy and implantation rates were recorded in the patients who received E(2) supplementation and were treated with the long GnRH analog protocol. CONCLUSION(S): For patients who are treated with the long GnRH analog protocol for controlled ovarian hyperstimulation and for whom luteal support with hCG is contraindicated, the addition of E(2) to the progestin support regimen may have a beneficial effect on pregnancy and implantation rates.

Adult↗
PubMed2000

Reduction of exercise-induced asthma oxidative stress by lycopene, a natural antioxidant.

BACKGROUND: Lycopene has previously been shown to have high antioxidative activity. In view of the controversy regarding the beneficial effect of antioxidants on asthma, the acute effects of lycopene (LYC-O-MATO) on airway hyperreactivity were assessed in patients with exercise-induced asthma (EIA). METHODS: Twenty patients with EIA participated in our study to verify the antioxidative effects. The test was based on the following sequence: measurement of baseline pulmonary function, 7-min exercise session on a motorized treadmill, 8-min rest and again measurement of pulmonary function, 1-week, oral, randomly administered, double-blind supplementation of placebo or 30 mg/day of lycopene (LYC-O-MATO), measurement of pulmonary function at rest, 7-min exercise session, and 8-min rest and again measurement of pulmonary function. A 4-week washout interval was allowed between each protocol. RESULTS: All patients given placebo showed significant postexercise reduction of more than 15% in their forced expiratory volume in 1 s (FEV1). After receiving a daily dose of 30 mg of lycopene for 1 week, 11 (55%) patients were significantly protected against EIA. Serum analyses of the patients by high-pressure liquid chromatography detected in the lycopene-supplemented patients an elevated level of lycopene compared to the placebo group, with no change in retinol, tocopherols, or in the other carotenoids. CONCLUSIONS: Our results indicate that a daily dose of lycopene exerts a protective effect against EIA in some patients, most probably through an in vivo antioxidative effect.

Adolescent↗
PubMed1999

Prevention of exercise-induced asthma by a natural isomer mixture of beta-carotene.

BACKGROUND: The unicellular alga Dunaliella bardawil was previously shown to contain very high concentrations of beta-carotene composed of equal amounts of the all-trans and 9-cis stereoisomers which differ in their physicochemical features and antioxidative activity. Due to the controversy regarding the beneficial effect of antioxidants on asthma, the acute effects of beta-carotene of Dunaliella was assessed on airway hyperreactivity in patients with exercise-induced asthma (EIA). METHODS: Thirty-eight patients with EIA participated in our study to verify the antioxidative effect. The test was based on the following sequence: baseline pulmonary function, 7 minutes exercise session on a motorized treadmill, 8 minutes rest, 1-week oral random, double-blind supplementation of placebo or 64 mg/day beta-carotene, pulmonary functions at rest, 7 minutes exercise session, 8 minutes rest and again pulmonary functions. RESULTS: All patients given placebo showed a significant postexercise reduction of more than 15% in their forced expiratory volume in one second (FEV1). Of the 38 patients who received a daily dose of 64 mg of beta-carotene for 1 week, 20 (53%) were protected against EIA. CONCLUSIONS: Our results indicate that a daily dose of Dunaliella beta-carotene exerts a protective effect against EIA in some patients most probably through in vivo antioxidative effect.

Administration, Oral↗
PubMed1997

Blocking effect of vitamin C in exercise-induced asthma.

OBJECTIVE: To determine if vitamin C (ascorbic acid) has a protective effect on the hyperreactive airways of patients with exercise-induced asthma (EIA). DESIGN: All the patients underwent pulmonary function tests at rest, before and 1 hour after receiving 2 g of oral ascorbic acid. They were then randomly assigned in a double-blind manner to receive 2 g of ascorbic acid or a placebo 1 hour before a 7-minute exercise session on a treadmill. Pulmonary function tests were performed after an 8-minute rest. This procedure was repeated 1 week later, with each patient receiving the alternative medication. SETTING: A university hospital. PARTICIPANTS: Twenty patients with asthma (13 males and 7 females), with ages ranging from 7 to 28 years (mean, 13.8 years). All patients who had a decline of at least 15% in their forced expiratory volume in 1 second after a standard exercise test on a motorized treadmill received a diagnosis of EIA. MAIN-OUTCOME MEASURES: All patients were advised to stop using their regular asthma medication or bronchodilator 12 hours before the test. Pulmonary function tests were performed in the same ambient conditions on all patients. RESULTS: All patients received a diagnosis of EIA. Ascorbic acid administration did not change the results of pulmonary functions at rest after 1 hour. In 9 patients, a protective effect on exercise-induced hyperreactive airways was documented. Four of 5 patients who received ascorbic acid and documented a protective effect on EIA continued to receive ascorbic acid, 0.5 g/d, for 2 more weeks with the same protective effect. CONCLUSIONS: The efficacy of vitamin C in preventing EIA cannot be predicted. However, vitamin C may have a protective effect on airway hyperreactivity in some patients with EIA.

Administration, Oral↗
PubMed1997

Incubation with sperm enhances in vitro maturation of the oocyte from the germinal vesicle to the M2 stage.

OBJECTIVE: To evaluate the effect of sperm in the culture medium on the rate of oocyte maturation in vitro from the germinal vesicle to the M2 stage. DESIGN: Prospective randomized controlled study. SETTING: The IVF Unit, Wolfson Medical Center, Holon, Israel. PATIENT(S): All women in whom oocytes were retrieved at the germinal vesicle stage between December 1995 and March 1996. INTERVENTION(S): Oocytes retrieved at the germinal vesicle stage were divided prospectively and randomly into four groups of incubation conditions: group 1, intact germinal vesicle with cumulus; group 2, intact germinal vesicle with sperm cells in the culture medium; group 3, stripped germinal vesicle; and group 4, stripped germinal vesicle with sperm cells. Oocytes were observed 24 hours after retrieval, and the stage of maturation was recorded. Oocytes that reached the M2 stage underwent the intracytoplasmic injection procedure, and the fertilization rate in each group was recorded at 48 hours. MAIN OUTCOME MEASURE(S): Maturation rate from the germinal vesicle to M2 stage and fertilization rate. RESULT(S): Each group contained 20 germinal vesicle oocytes. In groups 1 and 2, 2 (10%) and 9 (45%) oocytes, respectively, reached the M2 stage at 24 hours; at 48 hours, 1 (5%) and 8 (40%) embryos developed, respectively. The results in group 2 were significantly higher than in group 1. In groups 3 and 4, 6 (30%) and 16 (80%) oocytes, respectively, reached the M2 stage at 24 hours; at 48 hours, 5 (25%) and 14 (70%) embryos developed, respectively. Results in group 4 were significantly higher than those in groups 1, 2, and 3. CONCLUSION(S): Both methods of oocyte activation (i.e., addition of sperm to the culture medium or removal of the cumulus) enhance oocyte maturation in vitro, but the sperm-incubation method has a more pronounced effect. A combination of both methods leads to an exceptionally high rate of oocyte maturation, followed by a high fertilization rate.

Adult↗
PubMed1996

[Imaging of peripheral cholangiocarcinoma. Comparison with pathological anatomy].

OBJECTIVE: Peripheral cholangiocarcinoma is a rare malignant intrahepatic tumor which originates in the distal bile duct. Our purpose was to identify the imaging characteristics of peripheral cholangiocarcinoma and to establish a correlation with surgical and histopathologic findings. METHODS AND MATERIALS: The imaging data of 16 patients with proven cholangiocarcinoma were retrospectively reviewed by sonography in 13 cases, computed tomography in 13 cases, magnetic resonance imaging in 6 cases, and angiography in 10 cases and correlated with surgical and histopathologic findings. RESULTS: In most cases peripheral cholangiocarcinoma appeared as a single, large (> 10 cm), heterogeneous, and non encapsulated mass. On precontrast computed tomography, the lesions were mostly low density. Enhancement was moderate in the bolus phase and increased in the delayed scan. With magnetic resonance imaging, lesion signals were low intensity in T1-weighted images and variable intensity in T2-weighted images. On angiogram, lesions were often hypovascular. Associated features were frequently observed: portal encasement (69%), lobar atrophy or capsular retraction (43%), dilated intrahepatic bile ducts (30%), extension into the hepatic capsule (23%), and inferior vena cava extension (15%). Radiopathologic comparison showed that imaging modalities accurately identified vascular encasement, but underestimated extrahepatic tumor extension. CONCLUSION: In most cases, peripheral cholangiocarcinoma has a typical appearance which may be helpful in differentiating this disease from other intrahepatic tumors.

Adult↗
PubMed1994

[Radiological exploration of the thorax. Strategy and indications].

The widespread use of computed tomography and the advent of magnetic resonance imagery have considerably modified the methods and strategies of thoracic exploration over the last 10 years. Standard radiography remains the first-line examination for all thoracic diseases, and often is the only imagery required; further explorations are indicated on the basis of the information seen on standard films. Computed tomography has become an essential element in the work-up of all diseases involving a tumoural process in the lung. It is also indicated in bronchiestasis and for the exploration of chronic lung diseases. Further information may be obtained with magnetic resonance imagery. Although this method cannot be used to explore the pulmonary parenchyma, it is particularly adapted in cases involving the pleura, mediastinum (tumours and vessels) and the thoracic wall. Scintigraphy is mainly used to detect pulmonary migrations and to investigate lung function before thoracic surgery. Pulmonary angiography remains the reference imagery for the diagnosis of pulmonary embolism but has lost its other indications. Tomobronchography is exceptionally required. Current strategy in infectious diseases is to always begin with standard radiography, then to complete the work-up with further examinations only when necessary. Correct evaluation of tumoural processes relies heavily on tomography even for very small masses since it provides essential information on localization and extension. Management of primary bronchogenic cancers also requires repeated tomographic studies. Magnetic resonance images are indicated on the basis of the tomography results and are particularly useful in tumours of the apex and extension to the spinal column or mediastinum. For chronic bronchopathy, pulmonary scintigraphy is performed after standard films in the preoperative work-up then is sometimes completed with other techniques. In cases of suspected pulmonary emboli, a normal scintigraphy can eliminate the diagnosis. Inversely, certain teams propose coupling perfusion scintigraphy with ventilation scintigraphy to detect mismatches, particularly distinctive signs of pulmonary emboli. When the diagnosis remains uncertain, pulmonary angiography is the reference imagery technique.

Angiography↗
PubMed1994

Open window thoracostomy, myoplasty, and epiploplasty for treatment of postpneumonectomy empyema: CT evaluation.

PURPOSE: To demonstrate the computed tomographic (CT) appearance of the postpneumonectomy space (PPS) after surgical treatment of postpneumonectomy empyema. MATERIALS AND METHODS: The authors retrospectively reviewed 22 CT scans obtained in 15 patients after open window thoracostomy (OWT) (n = 4), myoplasty (n = 12), and epiploplasty (n = 1). RESULTS: After uncomplicated OWT, the retracted PPS contained air and/or gauze without residual pleural fluid. After uncomplicated myoplasty, marked retraction of the operated hemithorax was observed. CT allowed localization of transposed muscle flaps and fatty tissue within the PPS. A moderate amount of fluid and air was present during the 1st month after surgery. After uncomplicated epiploplasty, the retracted PPS contained homogeneous tissue with characteristic fatty attenuation. Complications including recurrent empyema, recurrent bronchopleural fistula, aseptic fluid collection, necrosis and fatty transformation of muscle flaps, and tumor recurrence were accurately demonstrated. CONCLUSION: CT is useful in follow-up after surgical treatment of postpneumonectomy empyema because it permits accurate evaluation of the PPS.

Aged↗
PubMed1994

Hepatic adenoma: MR findings in 51 pathologically proved lesions.

PURPOSE: To describe the magnetic resonance (MR) imaging features of hepatic adenoma and correlate these findings with histopathologic findings. MATERIALS AND METHODS: MR findings of 51 pathologically proved hepatic adenomas in 29 consecutive patients were retrospectively analyzed. T1- and T2-weighted spin-echo (SE) images were obtained in all patients, and contrast material-enhanced MR images were obtained in 16 patients. RESULTS: At pathologic analysis, a peripheral rim, observed in 16 (31%) hepatic adenomas, corresponded to pseudocapsule, and tumor heterogeneity, observed in 26 (51%) lesions, corresponded to hemorrhagic necrosis and peliosis. Hyperintensity on T1-weighted SE images was observed in 30 (59%) adenomas; 10 (67%) of 15 hepatic adenomas were hyperintense on contrast-enhanced gradient-echo images, and 13 (45%) of 29 were hyperintense on delayed contrast-enhanced T1-weighted SE images. CONCLUSION: Presence of a peripheral rim, heterogeneity, and hyperintensity are common features of hepatic adenoma.

Adenoma↗
PubMed1993

MR imaging in intracystic hemorrhage of simple hepatic cysts.

Intracystic hemorrhage of simple hepatic cysts is one of the most frequent complications. Ultrasonography (US) and computed tomography (CT) may show abnormal findings and mimic other diseases. We describe magnetic resonance (MR) imaging in four patients with intracystic hemorrhage confirmed by surgery or percutaneous aspiration. In all cases the lesions were hyperintense on both T1- and T2-weighted sequences. In three of the four cases the signal was heterogeneous on T1-weighted sequences. Two cases of a thickened wall and one case of a fluid-fluid level were also observed. We suggest that MR imaging may be helpful to differentiate intracystic hemorrhage from other cystic lesions by showing high signal on T1- and T2-weighted sequences.

Aged↗
PubMed1992

Facial nerve neuromas: MR imaging. Report of four cases.

Four cases of facial nerve neuroma were evaluated by computed tomographic (CT) scan and magnetic resonance imaging (MRI). The extension of the tumor in the petrous bone or the parotid gland was well defined by MRI in all cases. CT scan was useful to demonstrate bone erosions and the relation of the tumor to inner ear structures. In cases of progressive facial palsy, CT and MRI should be combined to detect a facial neuroma and to plan the surgical approach for tumor removal and nerve grafting.

Adult↗
PubMed1992

Haemangioma of the petrous bone: MRI.

Gd-DTPA-enhanced MRI provided accurate demonstration of the site and extension of a haemangioma of the petrous bone. Enhanced-MRI could allow early detection and differentiation from the other more common tumours of the geniculate ganglion area, thereby permitting the surgeon to remove the tumour, while preserving the facial nerve. CT is, however, required to display the characteristic ossification in these tumours.

Contrast Media↗