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J Landman

Publications and source records attributed to J Landman.

At least 19 recordsLinked to original sources
PubMed2005

Evaluation of surgical performance with standard rigid and flexible-tip laparoscopes.

BACKGROUND: Flexible-tip laparoscopes have recently been introduced into clinical practice, with the goal of improving surgeon performance during complex laparoscopic procedures. We used objective and subjective performance parameters to compare standard rigid 0 degrees and 30 degrees lens laparoscopes two flexible-tip laparoscopes in an in vitro model. METHODS: Twenty-nine subjects with varied levels of surgical experience performed complex laparoscopic tasks in three different models simulating (a) prostate dissection from the rectum, (b) cystic duct clipping, and (c) distal posterior rectum dissection. Each task was performed using two Storz rigid laparoscopes (0 degrees and 30 degrees) and two flexible-tip laparoscopes, the Olympus LTF-V3 and the Fujinon EL2-TF310. The sequence of application of the two flexible-tip laparoscopes was randomized. In each case, an experienced laparoscopic camera driver controlled the field of vision. Time to complete each task, operative precision, and subjective surgeon rating scores were compared. Statistical analysis was performed with analysis of variance (ANOVA) and a two-sided fisher's exact test. RESULTS: In all three models, the flexible laparoscopes offered no advantage in terms of procedure time, surgical precision, or subjective surgeon rating score when compared with the 30 degrees lens rigid laparoscope. The 30 degrees rigid lens laparoscope and the two flexible-tip laparoscopes were superior to the 0 degrees lens rigid laparoscope for all parameters evaluated, with the exception of subjective rating in the cystic duct model and procedure time in the colorectal model. CONCLUSION: In this in vitro experimental model, the flexible-tip laparoscopes found to have no advantage over the standard rigid 30 degrees lens laparoscope. These models were validated, as the 0 degrees lens rigid laparoscope was surpassed by the 30 degrees lens rigid laparoscope and the flexible-tip laparoscopes. Both flexible-tip laparoscopes produced similar results and excellent image quality, but some experience is required before their smooth application can be achieved.

Adult↗
PubMed2005

Listing of common HLA alleles and haplotypes based on the study of 356 families residing in the Paris, France, area: implications for unrelated hematopoietic stem cell donor selection.

In this study we have identified frequent human leukocyte antigen (HLA)-A, -B, -C,-DRB1, and -DQB1 alleles, frequent HLA-B/C, HLA-DRB1/DQB1 two-allele associations, and the most common HLA-A/B/C/DRB1/DQB1 five-locus haplotypes in a population residing in the Paris, France, area. The study was carried out in 356 families of children awaiting hematopoietic stem-cell transplantation (HSCT), with the selection criterion that haplotypes could be assigned with certainty to both the patient and at least one parent. Parental haplotypes were HLA-A, -B serologically typed, and HLA-C, -DRB1, -DQB1 broadly typed by polymerase chain reaction-sequence-specific oligonucleotide probe. The alleles of the most frequent haplotypes were subsequently defined at a high-resolution level by polymerase chain reaction-sequence-specific primer. The results on the distribution of common alleles and common allele associations demonstrated similarities with the previously published data in Caucasian populations, as expected from the geographic origin of the studied population. More importantly, this study provides the largest listing of common B/C and DRB1/DQB1 associations and of common five-allele haplotypes defined with certainty in a Caucasian population to date. These results can be used to help estimate the likelihood of finding a suitable donor in unrelated HSCT and to delineate search strategies for potential donors.

Alleles↗
PubMed2002

Assessing the diet of the British African-Caribbean population: frequency of consumption of foods and food portion sizes.

There is a very high prevalence of diet related disorders in the British African-Caribbean population but very few studies have determined associations between diet and disease within this community. There are virtually no published data on the frequency of foods consumed by this population or on the usual portion sizes which are necessary not only for nutritional epidemiological studies but also for treating diet related conditions such as diabetes. Here we present the frequency of foods consumed, assessed by a quantitative FFQ specifically developed for this sample, and the usual portion size reported by 210 randomly selected adult men and women. Frequency of consumption of foods and food portion sizes reported differed greatly from those consumed by the majority White population. This paper highlights the need to collect valid food consumption data for specific ethnic groups rather than using data available from another population, which is inappropriate. Such data will enable more precise dietary assessment and will further our understanding of the role of diet in the aetiology and prevention of diet-related diseases.

Black or African American↗
PubMed2001

Dual-organ ablative surgery using a hand-assisted laparoscopic technique. A report of four cases.

In clinical situations where more than one procedure is required, a properly positioned hand-assist device can be used to obviate the need for two large incisions. We present four cases of hand-assisted laparoscopic nephrectomy combined with a simultaneous second organ extraction. Each of the four primary procedures, as well as one of the four secondary procedures, was performed using a hand-assisted laparoscopic technique. In two cases, the secondary procedure was performed with an open surgical technique through the hand-assist incision. For the remaining secondary procedure, we used a laparoscopically assisted technique.

Aged↗
PubMed2001

Comparison of renal ablation with cryotherapy, dry radiofrequency, and saline augmented radiofrequency in a porcine model.

BACKGROUND: Needle ablative therapy has recently generated a lot of interest in the urologic community. We compare renal lesions produced in a porcine model using three forms of needle ablative energy: cryoablation (CR), dry radiofrequency (RF), and saline augmented radiofrequency (SARF). STUDY DESIGN: In 10 farm pigs, under ultrasonographic guidance, 40 laparoscopic renal lesions were produced: 825-mm CR lesions were produced with 2.4-mm cryoprobes (Endocare Inc, Irvine, CA), after 1-mL preinfusions of 14.6% saline, 12 SARF lesions were created with 22-gauge needles (2 mL/minute 14.6% saline, 50 W 510 kHz RF for 60 seconds), 12 RF lesions were created with a 2-cm array LeVeen electrode and an RF2000 generator using impedance limited 30 to 60 W double activations (Radiotherapeutics Corp, Mountain View, CA), and 8 RF lesions were produced using 22-gauge needles and double 10 W activations with the RF2000 generator. Eight animals were sacrificed after 1 week for acute pathology. An additional two animals were sacrificed at 8 weeks to provide chronic pathology results for the LeVeen dry RF and SARF modalities. RESULTS: CR produced a regular 18- to 22-mm zone of complete necrosis bordered by a 1.5- to 2.5-mm zone of partial necrosis. Acutely, LeVeen RF and single-needle RF produced lesions 25 to 45 mm and 6 to 10 mm wide, respectively. Acutely, SARF produced irregular cone-shaped lesions 15 to 31 mm wide. Only one of eight acute LeVeen RF lesions showed complete necrosis; none of the four 8-week LeVeen RF lesions displayed complete necrosis. Two of the four 8-week SARF lesions displayed complete necrosis. The remainder of the LeVeen RF, single-needle RF, and SARF lesions showed early, indeterminate tubular damage with relative glomerular sparing and bands of complete necrosis (0.5 to 1.5 mm) and inflammation (0.5 to 2 mm) at the periphery. Only CR could be consistently monitored with laparoscopic ultrasonography. CONCLUSIONS: Renal cryoablation produces well-defined, completely necrotic lesions that can be monitored reliably with ultrasonography. Longer followup may be required to characterize the full extent of renal necrosis produced by RF, but in the short run, none of the RF modalities reliably produced 100% necrosis in all cases.

Animals↗
PubMed2001

A review of ethnicity, health and nutrition-related diseases in relation to migration in the United Kingdom.

OBJECTIVES: To identify lessons from and gaps in research on diet-disease links among former migrants in the United Kingdom (UK). RESULTS: Migrant status and self-identified ethnicity do not match so these terms mask differences in social, nutritional and health status within and between population groups. Some former migrants differ in causes of death from the general population, e.g.: fewer coronary heart disease deaths among Caribbean-born; fewer cancer deaths among Caribbean, South Asian- and East African-born adults. Irish- and Scottish-born have higher mortality from all causes. Experience of risk factors differ also, e.g.: higher prevalences of hypertension and diabetes in Caribbean- and South Asian-born adults than representative samples of the general population; obesity and raised waist-hip circumference ratios in South Asian, African-Caribbean and some Irish-born adults. Former migrants experience long-term disadvantage, associated with more self-defined illness and lower reported physical activity. Nutrient intake data from the few, recent, small-scale studies must be interpreted with caution due to methodological diversity. However, second generation offspring of former migrants appear to adopt British dietary patterns, increasing fat and reducing vegetable, fruit and pulse consumption compared with first generation migrants. CONCLUSIONS: There is insufficient evidence on why some former migrants but not others experience lower specific mortality than the general population. Dietary intake variations provide important clues particularly when examined by age and migration status. Majority ethnic and younger migrant groups could raise and sustain high fruit and vegetable intakes but lower proportions of fat, by adopting many dietary practices from older migrants. Objective measures of physical activity and longitudinal studies of diets among different ethnic groups are needed to explain diversity in health outcomes and provide for evidence-based action.

Africa↗
PubMed2001

Comparison and analysis of laparoscopic intracorporeal suturing devices: preliminary results.

BACKGROUND AND PURPOSE: One of the most challenging aspects of laparoscopic surgery is intracorporeal suturing and knot tying. A loss of depth perception and tactile sense and visual obstruction make placing accurate and well-tied knots a difficult and time-consuming task. Two devices conceived to ease the task of suturing and knotting while presumably speeding performance are the Suture Assist (SA; Ethicon Endo-Surgery) and EndoStitch (ES; US Surgical/Tyco). We set out to objectively assess suture placement accuracy and knot speed and strength of these two suturing devices and conventional laparoscopic suturing (CS). MATERIALS AND METHODS: To date, six surgeons with laparoscopic experience were trained on the three suturing techniques. A pelvic trainer was set up with a freshly marked and incised swine renal pelvis and ureter. Each surgeon placed four sutures of 2-0 polyester suture with each technique (repeated on three separate occasions) with five half-hitches for a total of 216 knots. Time, strength, and accuracy were measured for each suture/knot placement. The knot distance was then measured from the marked target using calipers and carefully dissected from the tissue. Each knot was individually tested on a Monsanto Model 10 tensiometer, whereby slippage, strength, and breakage points were determined. RESULTS: The mean times (min:sec) and accuracy (millimeters) were as following: CS 5:08 and 0.457, ES 2:45 and 0.660, and SA 2:40 and 0.508. The difference in time was found to be statistically significant (P < 0.001), while the difference in accuracy was not. Only 182 of 216 knots were able to be included for analysis because of either a small knot lumen or device failure. Device failures necessitating intervention were encountered only with the SA, which had a misfire rate of 9.7% (7 of 72). The mean knot strength was measured at 41.1 N for CS, 57.3 N for SA, and 28.0 for ES. Knot break percentage (breakage) was calculated as 50.8% for CS, 20.7% for ES, and 95% for SA. CONCLUSION: Preliminary results show that each of the laparoscopic suturing devices has distinct advantages over conventional intracorporeal suturing and tying. Decreased times and comparable, if not greater, knot strengths may translate into improved laparoscopic suturing/tying performance for laparoscopic intracorporeal suturing devices.

Equipment Design↗
PubMed2001

Ureteral access for upper urinary tract disease: the access sheath.

Ureteral access with the flexible ureteroscope remains a challenge for the urologist. The routine use of a newly developed, site-specific ureteral access sheath facilitates entry into the ureter for fragmentation and basket extraction of ureteral and renal calculi. The step-by-step technique of ureteral access with the Access Sheath is described.

Equipment Design↗
PubMed2001

Assessment of optimal balloon size for rupture of the ureteropelvic junction and mid-ureter in a porcine model.

PURPOSE: Balloon dilation potentially represents a safer and simpler technique for the treatment of ureteropelvic junction (UPJ) obstruction and ureteral strictures. Using a porcine model, we sought to establish the optimal balloon size for endoballoon rupture of the UPJ and ureter. MATERIALS AND METHODS: The efficacy of endoballoon rupture of the proximal and middle ureter with 24F, 30F, and 36F balloon catheters was compared in 19 female minipigs. At the proximal ureter, the effect of the rate of dilation also was evaluated for each balloon size. Extravasation of methylene blue-stained contrast material was assessed with retrograde pyelograms and direct laparoscopic vision. After acute sacrifice, the dilated segments were evaluated histologically with hematoxylin and eosin and Masson's trichrome staining. RESULTS: At the proximal ureter, free extravasation of contrast was observed in 61% of the rapid inflation and 72% of the slow inflation trials; contained extravasation was noted in 28% of the rapid inflation and 17% of the slow inflation trials. Except for two of the 24F slow inflation trials, all of the proximal ureteral trials produced at least one full-thickness tear into the periureteral fat. Grossly, the tears appeared linear with various lengths and no consistent orientation. Rapid inflation and increasing balloon size tended to produce a ureterotomy with less damage to the ureter surrounding the tear. At the mid-ureter, none of the balloon sizes consistently produced a transmural tear. CONCLUSIONS: Rapid dilation and use of a 36F balloon capable of maintaining a low profile after inflation may result in a cleaner proximal ureterotomy with less distortion of the untorn neighboring proximal ureter. Both 36F and 30F balloons consistently produced a full-thickness proximal ureterotomy in normal porcine tissue. For mid-ureteral strictures, balloon dilation to even 36F may fail to create a suitable ureterotomy. However, it must be noted that dysplastic or scarred tissue may respond differently to dilation than the more elastic normal porcine tissues used in this study.

Animals↗
PubMed2001

Vitamin D deficiency and insufficiency in Orthodox and non-Orthodox Jewish mothers in Israel.

BACKGROUND: The modest clothing that Orthodox Jewish women wear exposes very little of their skin to sunlight. Under these conditions they may develop vitamin D deficiency, even in sunny Israel. OBJECTIVES: To determine and compare the vitamin D nutritional status in Jewish orthodox mothers to that of non-orthodox mothers who live in the same metropolitan area in Israel. METHODS: 25-Hydroxyvitamin D was measured by competitive protein-binding radioassay in the sera of 341 Jewish Israeli mothers (156 orthodox and 185 non-orthodox). The sera were obtained 48-72 hours after childbirth during the late summer of 1998 and the spring of 1999. RESULTS: The mean (SD) serum concentration of 25-OHD was significantly (P < 0.002) lower (13.5 +/- 7.5 ng/ml) in the orthodox than in the non-orthodox mothers (18.6 +/- 9.6 ng/ml). Vitamin D deficiency (< 5 ng/ml) and insufficiency (< 10 ng/ml) were more common in the orthodox mothers (5.1% and 32.7% respectively) than in the non-orthodox mothers (2.7% and 13%, respectively). In subgroups of mothers supplemented with 400 units of vitamin D daily during pregnancy, vitamin D deficiency and insufficiency were less common (2.2% and 13%, respectively) in orthodox and non-orthodox mothers (0% and 8.1%, respectively). Vitamin D insufficiency was more common in the winter than in the summer only among non-orthodox mothers. CONCLUSIONS: The high prevalence of vitamin D deficiency and insufficiency in Israeli mothers raises the question whether vitamin D supplements should be given to pregnant women in Israel, at least to orthodox mothers.

Adult↗
PubMed2001

Laparoscopic bilateral hand assisted nephrectomy for autosomal dominant polycystic kidney disease: initial experience.

PURPOSE: The laparoscopic technique for bilateral nephrectomy in patients with autosomal dominant polycystic kidney disease is technically difficult. The procedure may be more acceptable if alterations to the technique made it safer and easier to perform. We describe our initial experience with, and the feasibility and potential benefits of hand assisted laparoscopic nephrectomy for approaching these large kidneys in patients with autosomal dominant polycystic kidney disease. MATERIALS AND METHODS: This approach was successfully applied in 3 patients with end stage renal disease due to autosomal dominant polycystic kidney disease. After obtaining transumbilical pneumoperitoneum ports were placed in the umbilicus (12 mm.), sub-xiphoid in the midline (12 mm.) and subcostal in the midclavicular line on each side (12 mm.). The table was tilted 40 degrees away from the planned side of initial nephrectomy with the patient in the half lateral position. A 7 cm. midline incision was made that incorporated the umbilical port and a commercially available hand assistance device was positioned. One surgeon hand was inserted into the abdomen to serve as a retractor/blunt dissector, while the other operated the electrosurgical instruments. The right hand was inserted for left nephrectomy and the left hand was inserted for right nephrectomy. The laparoscope was passed via the sub-xiphoid port and the instruments were placed through the ipsilateral subcostal laparoscopic port. Nephrectomy was completed and the specimen was removed through the hand port incision by draining the cysts as they were exposed to view via the midline incision. When dissection was difficult, an additional port was placed in the anterior axillary line at the umbilical level. Some cysts were ruptured or aspirated to decrease overall kidney size and make extraction possible via the 6 to 7 cm. midline incision. RESULTS: All procedures were successfully completed. Mean operative time for bilateral hand assisted laparoscopic nephrectomy was 5.5 hours (range 4.5 to 6.6). Estimated blood loss was 200 cc or less. Patients resumed oral intake on postoperative day 1. The mean amount of parenteral analgesics required postoperatively was decreased. Mean hospital stay was 4.3 days but it was 3 days when considering nephrectomy only. Patients returned to normal activity after an average of 2 weeks. There was sustained resolution of preoperative discomfort based on pain analog scales. At 1 month or less all patients recorded absent pain. They uniformly noticed improved preoperative pulmonary and gastrointestinal symptoms CONCLUSIONS: Hand assisted laparoscopic nephrectomy in patients with autosomal dominant polycystic kidney disease makes bilateral nephrectomy a reasonable option. The bilateral procedure may be performed as rapidly as laparoscopic only, unilateral nephrectomy in these cases. The advantages of the hand assisted approach include using tactile sensation to facilitate dissection, rapid blunt finger dissection, hand retraction and the application of immediate tamponade when needed. This procedure provides the benefits of minimal intraoperative blood loss, minimal postoperative pain, brief hospital stay and rapid convalescence in this group of patients at high risk.

Adult↗
PubMed2001

Missed anterior crossing vessels during open retroperitoneal pyeloplasty: laparoscopic transperitoneal discovery and repair.

PURPOSE: Extrinsic ureteropelvic junction obstruction due to anterior crossing segmental renal vessels is present in more than 50% of patients in adulthood. In this situation the ureter must usually be dismembered and transposed anterior to the crossing vascular structures, where it is anastomosed to the renal pelvis. Via the open retroperitoneal approach there may be a limited view of the anterior surface of the ureteropelvic junction and, hence, anterior crossing vessels may possibly be missed. We describe 2 patients with ureteropelvic junction obstruction in whom anterior vessels were missed during open retroperitoneal repair. Laparoscopic transperitoneal secondary pyeloplasty with posterior displacement of the crossing renal vessel was performed in each case. MATERIALS AND METHODS: Two patients presented with symptomatic congenital ureteropelvic junction obstruction after failed endopyelotomy in 1 and failed open retroperitoneal procedures in both. Preoperatively spiral computerized tomography angiography with a ureteropelvic junction protocol revealed crossing vessels in the 2 cases. This finding was confirmed at transperitoneal laparoscopic pyeloplasty. The ureter and renal pelvis were transposed anterior to the crossing vessels and 2 rows of running sutures were placed to complete the anastomosis. RESULTS: The 2 laparoscopic procedures were completed successfully. The anterior crossing vessels were preserved in each case. Currently the patients are asymptomatic and furosemide washout renal scan was normal. CONCLUSIONS: Spiral CT angiography reliably delineates the renal vascular anatomy in patients with ureteropelvic junction obstruction. This study may be valuable before planned open retroperitoneal ureteropelvic junction obstruction repair. Laparoscopic pyeloplasty may successfully manage anterior crossing vessels associated with secondary ureteropelvic junction obstruction.

Adolescent↗
PubMed2001

A European Master's Programme in Public Health Nutrition.

Effective population-based strategies require people trained and competent in the discipline of Public Health Nutrition. Since 1997, a European Master's Programme in Public Health Nutrition has been undergoing planning and implementation, by establishing initial quality assurance systems with the aid of funding from the European Commission (DG SANCO/F3). Partners from 17 European countries have been involved in the process. A European Network of Public Health Nutrition has been developed and accredited by the European Commission.

Adult↗
PubMed2000

Concomitant laparoscopic hand-assisted radical nephrectomy and open radical prostatectomy using a single lower midline incision.

The hand-assist technique offers the urologic surgeon several advantages. The technique provides the novice laparoscopist a logical segue into minimally invasive surgery by literally allowing one hand to remain in the realm of open surgery. Hand-assist access affords the laparoscopist the use of tactile sensation and blunt manual dissection and retraction. We describe an additional benefit of the hand-assist technique. In clinical situations in which more than one procedure is required, a properly positioned hand-assist device will avoid the need for two large incisions. We present simultaneous hand-assisted laparoscopic radical nephrectomy and open radical prostatectomy performed through a single midline incision.

Abdominal Muscles↗
PubMed2000

Laparoscopic renal ablation: an in vitro comparison of currently available electrical tissue morcellators.

OBJECTIVES: Morcellation with the Cook high-speed electrical laparoscopic (HSEL) morcellator in an impermeable nylon/plastic sack (LapSac) has remained unchanged since its inception nearly one decade ago. Sack deployment and specimen entrapment remain relatively difficult, and morcellation with this device is expensive and relatively slow. As such, in an effort to facilitate specimen entrapment and morcellation, we adapted two currently available electrical morcellators (the Steiner gynecologic morcellator and the electrical prostate morcellator [EPM]) for renal morcellation and compared them with the HSEL morcellator. METHODS: All morcellation was performed through a simulated abdominal wall under direct laparoscopic vision. Ten porcine kidneys were ablated with each of the following techniques: HSEL morcellation in a LapSac; HSEL morcellation in a fluid-filled LapSac; Steiner morcellation in an insufflated Endocatch sack; and EPM morcellation in a fluid-filled Endocatch sack. A modified laparoscopic trocar was constructed and used for the Steiner and EPM morcellation. The time to complete morcellation, morcellation product size, and entrapment sack integrity were evaluated for each technique. Cost data for each morcellator are also presented. RESULTS: The mean morcellation time for the Steiner, HSEL dry, HSEL wet, and EPM morcellation was 6.0, 15.9, 14.7, and 26.0 minutes, respectively. The mean fragment size for these morcellators was 2.97, 0.65, 0.62, and 0.013 g, respectively. A single entrapment sack perforation was documented in a LapSac during routine HSEL morcellation. CONCLUSIONS: Renal morcellation with all three morcellators is feasible. The Steiner morcellator combined with an Endocatch resulted in more rapid morcellation and larger morcellation products.

Animals↗