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G J Fuchs

Publications and source records attributed to G J Fuchs.

At least 91 records · Page 5Linked to original sources
PubMed1997

Prostate heating patterns comparing electrosurgical transurethral resection and vaporization: a prospective randomized study.

PURPOSE: A prospective study was performed to determine if transurethral electrosurgical vaporization of the prostate is associated with unseen heat damage to vital periprostatic structures compared to conventional loop resection. In addition, energy consumption and its relationship to observed tissue temperature at the prostate periphery were evaluated for each treatment. MATERIALS AND METHODS: Patients with moderate to severe symptoms of benign prostatic bladder outflow obstruction and objective evidence of diminished flow or acute urinary retention were randomized to undergo either transurethral loop resection or electrosurgical vaporization after stratification for gland volume. Instrumentation was standardized for both groups except for the monopolar electrode used. The radiofrequency power source in the study was a new computer controlled generator with a constant power delivery feature. Regional tissue heating patterns were evaluated with optical fiber probes in real time. Four stationary sites were chosen for temperature measurements, namely the lateral lobe of the prostate, neurovascular bundle beside the prostatic apex at the level of the external sphincter, and anterior rectal wall at the level of the prostatic base and apex. A pull back technique was used to search for hot points in the long axis of the probe (3-dimensional temperature mapping) in 2 patients from each group. Incident generator panel power settings for the electrosurgical vaporization treatments were equivalent to those commonly used for loop resection (150 watts) and were adjusted up or down as needed. RESULTS: Prostate electrosurgical vaporization was possible at generator panel settings that were nearly equivalent to those for transurethral resection of the prostate (130 to 190 watts). No significant rectal or sphincteric heating was detected with either procedure. Conductive cooling of the neurovascular bundles was observed in 2 patients in each group toward the end of the operation. More energy was used per minute of treatment during electrosurgical vaporization than with regular loop resection (p < 0.004) but this was not associated with unwanted tissue heating. CONCLUSIONS: Neither conventional loop resection nor electrosurgical vaporization of the prostate appeared to be unsafe treatments with respect to unseen deep heating effects to vital periprostatic structures when performed at equivalent low incident power. The extra energy used during electrosurgical vaporization provided the benefit of improved coagulative hemostasis concurrently with shallow tissue vaporization using pure cutting current alone, without compromising treatment safety.

Aged↗
PubMed1997

A multicenter clinical trial investigating the use of a fluoroscopically controlled cutting balloon catheter for the management of ureteral and ureteropelvic junction obstruction.

PURPOSE: We assessed the efficacy of a fluoroscopically controlled cutting balloon catheter for the treatment of ureteropelvic junction and ureteral strictures. MATERIALS AND METHODS: A multicenter trial was performed that included 66 endopyelotomies and 49 endoureterotomies. To our knowledge this study represents the largest number of patients with ureteropelvic junction obstruction and ureteral strictures tested with this device to date. RESULTS: With a mean followup of 7.8 months (range 1 to 17.9) the patency rate was 77% for endopyelotomy, with 72% of the primary and 100% of the secondary ureteropelvic junction obstructions remaining patent. The endoureterotomy patients were followed for an average of 8.7 months (range 1.2 to 17.0), with a patency rate of 55%. CONCLUSIONS: A cutting balloon endoscopic incision is effective in the majority of cases, with patency rates for endopyelotomies and endoureterotomies that mirror current endourological reports using other, albeit more time intensive and more invasive, incisional techniques.

Adolescent↗
PubMed1997

Shelf-life of pre-cooked rice oral rehydration salt packets.

The shelf-life of pre-cooked rice oral rehydration salts (ORS) at the household level was studied in urban Dhaka. To prepare the packets, cooked rice was dried and ground to fine powder and the salt ingredients were mixed according to the World Health Organization formulation. For each half liter packet, 10 g glucose was replaced by 25 g of instant cooked rice powder. The packets were kept in different environments for three months among 30 households of varying socioeconomic status. At monthly intervals, two packets from each family were collected for laboratory tests. Physical characteristics of ORS such as color and dispersibility remained the same throughout the three month study period. However, in the third month flavor changed slightly. The electrolyte concentration of the prepared solution remained the same at the end of the first, second and third months. However, progressive but minimal increase in moisture content of the packets was noted over the allotted time period. This increase in moisture was less when the mixture was packed in double thin layer polythene bags as opposed to the single layer bags. In conclusion, the shelf-life of pre-cooked rice ORS remains stable at least up to three months when stored at the household level. Therefore, pre-cooked rice ORS can be kept at households for future use in the event of diarrheal episodes.

Diarrhea↗
PubMed1997

Gastrointestinal allergy to food: a review.

Gastrointestinal food allergy still poses a challenge to the clinician because of its variable symptomatology and lack of reliable diagnostic tests. Its prevalence is estimated at 2 approximately 5%, higher in children than in older age-groups. Allergy to food usually diminishes with advancing age. Although a wide variety of foods can cause allergic reactions, cow's milk is the most common cause of food allergy in infants and young children. Depending upon the speed of onset of symptoms, immediate and delayed types of food allergy have been described. Gastrointestinal symptoms in food allergy have been explained by alterations in transport across the intestinal wall (increased secretory and/or decreased absorptive functions), increased permeability, and motility of the intestine. The exact pathogenesis of food allergy is still not clear. However, immediate type of food allergy is believed to be mediated by type I hypersensitivity reaction, involving mast cells and food-specific IgE antibodies. The diagnosis of food allergy is based upon a favorable response to an elimination diet and a response to a challenge with the suspected food. The condition is treated by eliminating the allergenic food from diet for as long as 9-12 months in case of cow's milk allergy. While exclusive breast-feeding for the initial four months or more reduces the chances of development of food allergy, the role of diet restrictions in the mother in reducing the incidence of food allergy in the infant is controversial. Data on food allergy from developing countries are limited. This may be due to lack of diagnosis or less attention given to the condition relative to other diseases including infectious diarrheas and acute respiratory infections. The role of cow's milk allergy in the pathogenesis of persistent diarrhoea, a major problem in the developing world, remains speculative. Frequent intestinal infections and reduced secretory IgA, which are associated with malnutrition, alter intestinal permeability and result in an increased uptake of food antigens. The increased antigenic load combined with factors such as an atopic predisposition may initiate an abnormal mucosal immune response resulting in chronic enteropathy.

Adult↗
PubMed1996

Changing epidemiology of cholera due to Vibrio cholerae O1 and O139 Bengal in Dhaka, Bangladesh.

At the International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDR, B) Dhaka we studied the trends in cholera for the period January 1992 to May 1995. Vibrio cholerae O139 Bengal emerged as a second aetiologic agent of cholera in Dhaka in January 1993. In 1993, the majority of cholera cases was due to V. cholerae O139, with V. cholerae O1 accounting for a small proportion of cases. During the latter part of the study period (Jan 1994-May 1995), V. cholerae O1 re-emerged as the predominant cholera strain. The predominant age group affected in endemic cholera due to V. cholerae O1 was children 2-9 years old, and the organism was isolated from more females than from males at all ages. In contrast, cholera due to V. cholerae O139 caused disease mostly in adults 15 years and older, which indicated that this organism was new in this population. As with V. cholerae O1, V. cholerae O139 was isolated from more females than males. The initial rapid emergence and predominance of V. cholerae O139 was considered possibly to herald the start of the eighth pandemic of cholera. However, just after a year, the prevalence of V. cholerae O139 decreased dramatically with V. cholerae O1 resuming the role of the dominant cholera strain. The factor(s) contributing to the dramatic decline in prevalence of V. cholerae O139 is not well understood.

Adolescent↗
PubMed1996

Iron deficiency and anaemia in children with a high prevalence of haemoglobinopathies: implications for screening.

BACKGROUND: Haemoglobin (Hb) concentration is used as a sole test for iron deficiency anaemia (IDA) in most developing countries since most anaemia is believed to be due to iron deficiency and confirmatory testing is generally unavailable. Yet the validity of this approach in regions where haemoglobinopathies are endemic has not been documented. METHODS: Haemoglobin and serum ferritin (SF) were measured in 559 Northern Thai children aged 6 months to 13 years of age. The sensitivity of SF to identify iron deficiency was also assessed in a subsample of children with low or low-normal Hb and normal SF by testing the Hb response to a trial of oral iron. RESULTS: While anaemia was common (27%), IDA constituted 19% and none of all anaemia in preschool and school age children, respectively (P < 0.002). Iron depletion was similarly more prevalent in younger children (P < 0.002). Children with IDA were younger (P < 0.001) and the anaemia more severe (P < 0.0001) compared to those with non-IDA. Of anaemic children with normal SF values who received a therapeutic trial of iron, only 6% responded with an increase in Hb of > or = 1 g/dl. CONCLUSIONS: For populations such as ours most anaemia is not due to iron deficiency and a single Hb determination is therefore not acceptable for a presumptive diagnosis of IDA.

Adolescent↗
PubMed1996

Risk factors for deaths in under-age-five children attending a diarrhoea treatment centre.

Few case-control studies have examined possible risk factors for diarrhoeal deaths in under-age-five children in the developing countries. We analysed data from the surveillance system of our diarrhoea treatment centre/hospital for the period 1990-94 on 928 children less than 5 years of age. In univariate analysis, 11 factors were significantly associated with death: lack of breastfeeding, severe malnutrition, complicated diarrhoea, pneumonia, xerophthalmia, duration of diarrhoea 7-14 days, moderate or severe dehydration, recent history of measles, Shigella flexneri infection, maternal illiteracy, and very low household income. Rotavirus diarrhoea was negatively associated with fatal outcome. In the assessment of severe malnutrition, weight-for-height measurement discriminated mortality risk better than weight-for-age or height-for-age indices. Only two factors retained their significance, severe malnutrition and non-breastfeeding in the multivariate analysis with adjusted odds ratio (95% confidence interval) of 84.2 (9.1, 775.9) and 4.2 (1.3, 13.2) respectively.

Anthropometry↗
PubMed1996

Nutritional factors and thalassaemia major.

Abnormal growth is a common feature of thalassaemia major in children. In an attempt to determine whether it has a nutritional cause, 12 children aged 1 to 3 years with thalassaemia major were studied under metabolic ward conditions. Nutritional status was assessed by anthropometry and biochemistry before and after an intensive nutrition regimen. Five children had wasting or stunting on admission. As a result of the nutrition intervention, mean weight for height improved significantly. The mean height increase of 0.4 cm after one month was not significant. Plasma zinc, depressed in half the children on admission, improved, as did alpha tocopherol, while copper decreased. Plasma insulin-like growth factor-I also increased commensurate with improved growth. Fat absorption was normal in all children. Undernutrition is an important cause of associated growth disturbances in children with thalassaemia major. Malnutrition was primarily caused by inadequate nutrient intake, as indicated by the capacity to gain weight appropriately when provided with nutrition support, and by the absence of intestinal malabsorption. While long term studies are required to determine if nutritional support will prevent stunting, these results underscore its central role in preventing nutritional deficiencies and in promoting normal growth in thalassaemic children.

Anthropometry↗
PubMed1996

[Current status of laparoscopic surgery in pediatric urology].

The current world-wide experience with laparoscopy in the field of pediatric urology is summarized. Based on significant personal expertise, the operative technique and instrumentation of the different procedures are described. Herein standard indications (i.e., diagnosis and therapy of cryptochidism, bilateral varicoceles) can be distinguished from rather infrequent procedures (i.e., renal cyst resection, nephrectomy) and experimental indications (case reports) such as bladder "auto" augmentation, antirefluxplasty and pyeloplasty. At the referring centers, laparoscopic surgery in pediatric urology has significantly increased. Therefore, this minimally invasive, delicate technique is becoming more popular.

Adolescent↗
PubMed1996

Malnutrition and growth abnormalities in children with beta thalassemia major.

Abnormal linear growth (stunting) is characteristic of children with beta thalassemia major and has been variably and inconsistently attributed to multiple different mechanisms. Despite the coexistence of beta thalassemia with deficits of several micronutrients, global undernutrition as a principle cause of growth abnormalities has not been adequately studied. We prospectively studied 115 nonsplenectomized children (6 months-6 years, 54 males, 61 girls) with beta thalassemia major who has not previously received chelation therapy. Most children had abnormal weight-for-age (WAZ) and height-for-age (HAZ) Z scores, however female children had lower WAZ (p < 0.0001) and HAZ (p < 0.02) compared to males. Mild to moderate degrees of acute wasting was also usual, and two males and one female had severe wasting. Severe weight deficits were more prevalent in the youngest (p < 0.01) and severe stunting in the older (p = 0.01) children. Nearly all children were < 50th percentile for both weight-for-age and height-for-age, and the majority were < 5th percentile. Of note, children were also disproportionately distributed below the 50th percentile for weight-for-height. Pre-transfusion hemoglobin was variably associated with anthropometric measurements. We conclude that not only is linear growth failure pervasive in our population with beta thalassemia major, but varying degrees of wasting are also typical. Further, weight deficits occur at an early age and appear to precede deficits in linear growth. Abnormal growth is not due to chelation therapy and is inconsistently associated with the degree of anemia. These patterns of growth abnormalities indicate general malnutrition as an important cause of growth failure in children with beta thalassemia.

Acute Disease↗
PubMed1995

[Flexible ureterorenoscopy: a method for minimally invasive diagnosis and therapy in the upper urinary tract].

Retrograde intrarenal surgery (RIRS) utilizing flexible, actively deflectable instruments has become a valuable asset in the diagnosis of upper urinary tract pathology and treatment of stone disease. Flexible endoscopic surgery of the proximal ureter and in the intrarenal collecting system constitutes the natural extension of rigid instrumentation in the upper urinary tract. At the UCLA Stone Center, retrograde ureteral and intrarenal surgery has become an integral part of our diagnostic and therapeutic armamentarium. This is documented by over 500 treatments and diagnostic procedures performed in the upper urinary tract during the past 5 years.

Anti-Bacterial Agents↗
PubMed1994

Relationship between vitamin A deficiency, malnutrition, and conjunctival impression cytology.

One hundred seventy-eight children from three villages were studied in a cross-sectional fashion to evaluate the efficacy of conjunctival impression cytology (CIC) to characterize vitamin A status of individual children and populations of children and to examine the relationship of vitamin A status to nutritional status. Although children with abnormal CIC results had lower retinol concentrations than those with normal CIC results (P < 0.02), CIC exhibited poor sensitivity and specificity. Results of a CIC prevalence criterion were concordant with plasma retinol criteria in characterizing the vitamin A status of each community. Plasma retinol measurements, but not CIC, were associated with height (P < 0.003) and severe stunting (P < 0.001). We conclude that although CIC was a poor indicator of an individual child's vitamin A status, it accurately characterized the risk of vitamin A deficiency of communities. Furthermore, vitamin A deficiency defined by circulating retinol measurements but not CIC is associated with poor linear growth.

Anthropometry↗
PubMed1994

Effect of dietary fat on cardiovascular risk factors in infancy.

OBJECTIVE: To determine the effects of feeding regimens of varying fat composition on dietary intake and serum lipid and lipoprotein concentrations in older infants. DESIGN, SETTING, AND PARTICIPANTS: One hundred four healthy infants aged 4 to 6 months were enrolled from private pediatric practices or public health clinics and were randomly assigned to one of four feeding groups until 12 months of age. INTERVENTIONS: Infants received whole cow milk or a standard infant formula (48% to 49% of energy as fat from butterfat or a soy-coconut oil blend, respectively) or one of two nearly identical investigational lower fat follow-up formulas (36% kcal from a fat blend of palm olein, corn, and safflower oils) as their primary food source in addition to table foods. MAIN OUTCOME MEASURES: Nutrient intakes during the study period were characterized qualitatively and quantitatively. Serum lipids, lipoprotein concentrations, and anthropometrics were determined at baseline and at 12 months of age (study completion). RESULTS: Total energy intake was equivalent among feeding groups. Infants fed cow milk had higher mean daily intakes of total fat, saturated fat, monounsaturated fat, and cholesterol. Linoleic acid intake by infants fed cow milk, including that from table foods, was insufficient to meet current recommendations. Mean serum total cholesterol was significantly higher in the infants fed cow milk at age 12 months, whereas mean low density lipoprotein and apolipoprotein B were lower in the infants fed the follow-up formulas. Infants consuming the infant formula or whole cow milk demonstrated greater increases in mean serum total cholesterol, low density lipoprotein, and apolipoprotein B by 12 months of age compared with infants ingesting follow-up formula. Ponderal, linear, and head circumference growth was equivalent among feeding groups. CONCLUSIONS: (1) Older infants fed lower fat formula have adequate total energy intake and normal growth. (2) The fat composition of the diets fed to the infants influenced serum lipid and lipoprotein profiles. (3) The fat composition of cow milk is inferior compared with commercial formulas. (4) The optimal fat blend for older infants including the consequences of the standard practice of adding high percentage of coconut oil to infant formulas should be defined further.

Animals↗
PubMed1993

Fluoroscopically guided incision of ureteral strictures in pigs with the cautery-wire balloon catheter: a phase 1 study.

We investigated a catheter that can longitudinally incise ureteral strictures under fluoroscopic guidance without the need for ureteroscopy and its attendant risks. The catheter consists of a low-pressure balloon and an overlying cautery wire; the balloon allows precise localization of the stricture, seen as a waist in the balloon, and the overlying cautery wire can be fluoroscopically oriented at the stricture. One to two centimeter ureteral strictures were created in 6 swine. Two to four weeks later strictures were incised in a retrograde or antegrade fashion with the cautery-wire balloon catheter, and double J stents placed for a duration of three weeks. In 5 of 6 renal units strictures improved anatomically with resolution of hydronephrosis at 3 to 4 months' follow-up. Urodynamic absence of obstruction was verified by Whitaker testing. In one animal, the tip of the catheter dislodged in the ureter with subsequent loss of the renal unit. The engineering error that lead to this complication has since been rectified. With correction of the aforementioned problem, this Phase 1 study has demonstrated the feasibility, safety and preliminary efficacy of the cautery-wire balloon catheter for endourologic management of ureteral strictures.

Animals↗
PubMed1993

Ureteral stents and flexible ureterorenoscopy.

Numerous methods of dilating the intramural ureter for ureteroscopy are effective when used by experts, but none is ideal. In the authors' experience, a ureteral stent left indwelling for 1 or, better, 2 weeks usually is the safest, most reliable, and least traumatic method.

Endoscopes↗
PubMed1993

Iron status and intake of older infants fed formula vs cow milk with cereal.

One hundred four infants were randomly assigned to receive whole cow milk plus iron-fortified cereal (WCM + C) in accord with the previous recommendations of the Committee of Nutrition/American Academy of Pediatrics (CON/AAP); one of two iron-fortified, follow-up formulas; or an iron-fortified infant formula. Mean iron intakes and vitamin C exceeded the recommended dietary allowance in all groups. By 12 mo of age, mean ferritin and mean corpuscular volume were lower in the WCM + C group and significantly more infants had serum ferritin concentrations < 12 micrograms/L. We conclude that infants 6-12 mo of age fed whole cow milk and iron-containing table food are at risk of developing depleted iron stores but not anemia. The iron insufficiency in these infants is not due to inadequate intake of iron or vitamin C, but probably to relatively poor bioavailability of iron in infant cereal.

Animals↗