Observations of the Interaction and Transport of Fine Mode Aerosols with Cloud and/or Fog in Northeast Asia from Aerosol Robotic Network (AERONET) and Satellite Remote Sensing.

Analysis of sun photometer measured and satellite retrieved aerosol optical depth (AOD) data has shown that major aerosol pollution events with very high fine mode AOD (>1.0 in mid-visible) in the China/Korea/Japan region are often observed to be associated with significant cloud cover. This makes remote sensing of these events difficult even for high temporal resolution sun photometer measurements. Possible physical mechanisms for these events that have high AOD include a combination of aerosol humidification, cloud processing, and meteorological co-variation with atmospheric stability and convergence. The new development of Aerosol Robotic network (AERONET) Version 3 Level 2 AOD with improved cloud screening algorithms now allow for unprecedented ability to monitor these extreme fine mode pollution events. Further, the Spectral Deconvolution Algorithm (SDA) applied to Level 1 data (L1; no cloud screening) provides an even more comprehensive assessment of fine mode AOD than L2 in current and previous data versions. Studying the 2012 winter-summer period, comparisons of AERONET L1 SDA daily average fine mode AOD data showed that Moderate Resolution Imaging Spectroradiometer (MODIS) satellite remote sensing of AOD often did not retrieve and/or identify some of the highest fine mode AOD events in this region. Also, compared to models that include data assimilation of satellite retrieved AOD, the L1 SDA fine mode AOD was significantly higher in magnitude, particularly for the highest AOD events that were often associated with significant cloudiness.

Observation-based study on aerosol optical depth and particle size in partly cloudy regions.

This study seeks to help better understand aerosol-cloud interactions by examining statistical relationships between aerosol properties and nearby low-altitude cloudiness using satellite data. The analysis of a global dataset of MODIS (Moderate Resolution Imaging Spectroradiometer) observations reveals that the positive correlation between cloudiness and aerosol optical depth (AOD) reported in earlier studies is strong throughout the globe and during both winter and summer. Typically, AOD is 30-50% higher on cloudier-than-average days than on less cloudy days. A combination of satellite observations and MERRA-2 global reanalysis data reveals that the correlation between cloud cover and AOD is strong for all aerosol types considered: sulfate, dust, carbon, and sea salt. The observations also indicate that in the presence of nearby clouds, aerosol size distributions tend to shift toward smaller particles over large regions of the Earth. This is consistent with a greater cloud-related increase in the AOD of fine mode than of coarse mode particles. The greater increase in fine mode AOD implies that the cloudiness-AOD correlation does not come predominantly from cloud detection uncertainties. Additionally, the results show that aerosol particle size increases near clouds even in regions where it decreases with increasing cloudiness. This suggests that the decrease with cloudiness comes mainly from changes in large-scale environment, rather than from clouds increasing the number or the size of fine mode aerosols. Finally, combining different aerosol retrieval algorithms demonstrated that quality assessment flags based on local variability can help identifying when the observed aerosol populations are affected by surrounding clouds.

Nosocomial outbreak of Candida parapsilosis fungemia related to intravenous infusions.

Candida parapsilosis is rarely isolated from blood cultures. Our hospital surveillance detected an increased rate of isolation of C parapsilosis during a four month period. Fourteen postoperative patients receiving intravenous (IV) hyperalimentation and eight burn patients receiving IV albumin were involved. Hectic fever, the major clinical manifestation, was seen in 61% of cases. Therapy in the postoperative patients consisted merely of discontinuing IV catheters and hyperalimentation, while amphotericin B was needed in five of eight burn patients to control persistent fungemia. Epidemiologic analysis identified a source of the organism in the IV-additive preparation room where C parapsilosis was found contaminating a vacuum system. Organisms apparently refluxed into IV bottles when aliquots were removed to accommodate additives. Of 103 patients who received fluids prepared with the contaminated system, 21% became infected with C parapsilosis. Infection surveillance was instrumental in detection and control of the outbreak. Routine guideline should be established to insure the sterility of IV fluids containing additives.

Lack of intrathyroidal tumor necrosis factor alpha in Graves' disease.

In vitro tumor necrosis factor alpha (TNF alpha) exerts a synergistic action on HLA class II expression and a cytotoxic action in FRTL-5 cells. Therefore, a role for TNF alpha as a local mediator of cell destruction in thyroid autoimmunity has been postulated. To elucidate the in vivo significance of these and other in vitro findings for the pathophysiology of Graves' disease we investigated 11 thyroid glands of patients suffering from Graves' disease for TNF alpha. In situ hybridization was done with a TNF alpha probe synthesized with T7 polymerase on a 750-base pair EcoRI fragment of the coding region. Primers at positions 152 and 854 in the TNF alpha copy DNA sequence were used for reverse polymerase chain reaction (PCR) amplification of TNF alpha in 5 patients. Immunohistological staining for TNF alpha was done with a mouse monoclonal antibody. We could not detect any TNF alpha and TNF alpha messenger RNA in thyroid tissue of 11 patients suffering mostly from relapsing Graves' disease by immunohistology and in situ hybridization as well as reverse PCR, respectively. A faint signal could be detected by reverse PCR in control thyroid tissue from a patient with recurrent goiter. This lack of intrathyroidal TNF alpha in relapsing Graves' disease is in accordance with a lack of increased TNF alpha production by T cell clones isolated from Graves' disease thyroid glands and contrasts with previous in vitro results. Since protective TNF actions have been demonstrated in other autoimmune diseases it could therefore be envisaged that the lack of intrathyroidal TNF alpha may be associated with the relapse of Graves' disease in our patients.

Factors affecting the occurrence of dark-cutting beef and selected carcass traits in finished beef cattle.

A data set was used to determine how various factors affect the occurrence of dark-cutting beef and selected carcass traits in finished beef cattle. Data were collected in 1989 and 1990 from one packer with plants located in Amarillo, TX; Boise, ID; Dakota City, NE; and Garden City, KS. The data set consisted of 3,659 lots consisting of 724,639 cattle. Compared with those at Boise and Dakota City, cattle slaughtered in Amarillo and Garden City had a higher incidence of dark cutters (1.1 vs .3%; P < .01) and a lower quality grade (50 vs 64% Choice plus Prime; P < .01). The highest incidences of dark cutters occurred during August, September, and October (1.1 to 1.4%; P < .01), with incidences of .4 to .7% during the other months. Carcass quality grade was higher during January, February, and March compared with May through November (60 to 62% Choice plus Prime vs 52 to 58%; P < .01). As the number of cattle in a lot increased, the incidence of dark cutters increased from .4 to 1.2% (P < .01), and quality grade declined from 62 to 52% Choice plus Prime (P < .01). As the mean weight of cattle in the lot increased, the incidence of dark cutters declined from .94 to .6% (P < .01), and carcasses grading Choice plus Prime increased from 56 to 62% (P < .01). With cattle held over a weekend or holiday, ("carry cattle") the incidence of dark cutters increased from .8 to 1.6% (P < .01). We conclude that packing plant location, month of the year, weight of cattle, carry cattle, and number of cattle in a lot are most likely to influence the incidence of dark cutters and carcass quality traits.

Influence of passage model, sampling site, and marker dosing time on passage of rare earth-labeled grain through Holstein cows.

Three duodenally cannulated, lactating Holstein cows were dosed with rare earth-labeled grain to evaluate effects of passage model, sampling site, and marker dosing time on digesta passage parameters. Cows were given ad libitum access to feed twice daily. Rare earth-labeled grain (applied by the 24-h immersion technique) was fed immediately before (Dy) or 2 h after (Yb) the morning feeding, and duodenal digesta and feces were sampled. Marker excretion curves were fit to a two-compartment, biexponential model, using curve peeling or to a series of two-compartment models, with one to six orders of gamma time-dependency in the fast compartment, using nonlinear regression. Passage estimates from the curve-peeled, biexponential model were similar to those from the best fit of the nonlinear models, which had three orders of gamma time-dependency. Ruminal passage rate of grain, averaged across models, sampling site, and dosing time, was .077/h. Estimates of time to first appearance of marker at the sampling site and mean retention times were longer (8 vs 1 h and 25 vs 17 h, respectively), but passage rates were similar, when determined from fecal compared with duodenal samples (P less than .05). Marker dosing time did not influence any of the parameters. It is concluded that both curve-peeling (linear regression) and nonlinear regression methods can be equally useful for evaluating passage kinetics of grain in dairy cows and that sampling site and time of marker dosing have little effect on passage parameter estimates.

Performance, digestion, and mastication efficiency of Holstein steers fed whole or processed corn in limit- or full-fed growing-finishing systems.

We conducted two trials to examine the effects of restricted vs full feeding and of grain processing method on feedlot performance, digestion, and mastication efficiency by Holstein steers in different growing-finishing systems. In Trial 1, 272 Holstein steers (177 +/- 9.98 kg) were blocked by weight and assigned to growing phase diets based on corn silage (SIL), steam-flaked corn that was either limit-fed (SFLF) or full-fed (SFFF), or whole corn that was limit-fed (WCLF) or full-fed (WCFF). Limit-fed steers were fed at levels predicted to allow daily gain of 1 kg/d. On d 112, all steers were switched to WCFF or SFFF diets until the mean BW of each treatment group was 545 kg. Overall, steers fed WCLF and SFLF during the growing phase and finished on SF were 8.1 and 6.6% more efficient at converting dietary ME to gain (P = .02 and .04, respectively) than steers in the SFFF group. In Trial 2, three ruminally and duodenally cannulated Holstein steers were fed whole (WC) and rolled corn (RC) diets at FF and LF intake in an incomplete replicated 2 x 2 switchback design. Ad libitum access to feed resulted in higher (P = .02) ruminal starch digestibility than did limit-feeding, and calves had higher total tract DM (P = .05) and starch (P = .03) digestion at the heavier BW. Limit-feeding whole corn resulted in increased particle size of masticate (P = .06) compared with full-feeding whole corn. Because of apparent differences in mastication efficiency between limit-fed and full-fed calves, grain processing method during periods of restriction and compensatory growth may be important considerations for managing growth in systems that incorporate limit-feeding.

Effect of steam-flaked sorghum grain density on performance, mill production rate, and subacute acidosis in feedlot steers.

Two trials were conducted to determine the effects of steam-flaked sorghum grain bulk density on animal performance, cost of production, and propensity to induce ruminal acidosis in feedlot steers. In Trial 1, 336 yearling steers (343 kg; SEM = .346) were fed diets for 125 d that contained sorghum grain (82.5%, DM basis) flaked to .283 (L), .322 (M), or .361 (H) kg/L (i.e., 22, 25, and 28 lb/bu). Steers fed L consumed 3.2% less DM than those fed H (linear, P < .05), resulting in 6.9% lower ADG (linear, P = .02) and 3.6% lower gain efficiency (linear, P < .15). Sorghum grain flaked to M and L had 16 and 46% greater starch gelatinization than H (measured using differential scanning calorimetry; linear, P = .002). Dressing percentage increased linearly (P < .05) with increasing flake density, but no other carcass measurements were affected by treatment. Increasing flake density increased mill production rate linearly (P < .01), resulting in the lowest energy usage per unit of flaked grain for the H treatment. Trial 2 was an acidosis challenge study that incorporated six ruminally cannulated steers (422 kg; SEM = .129) into a replicated 3 x 3 Latin square experiment. Reducing flake density resulted in linear reductions in ruminal pH following intake challenge at 3, 33, and 36 h after the d-12 challenge (P < .05). There was a linear increase in the area between the pH vs time curve and a line at pH 5.5 (P < .01) and 5.0 (P = .09) with decreasing flake density (28.0, 25.2, and 18.2 pH-hours below 5.5 and 9.6, 7.3, and 3.9 pH-hours below 5.0 for L, M, and H, respectively). Cattle consuming L also tended to have higher VFA concentrations (mM) at 36 h after challenge (P = .12). There was no significant treatment effect on ruminal lactate. Flaking sorghum grain to .283 and .322 kg/L resulted in reduced intake and poorer animal performance compared with .361 kg/L (58.7% starch gelatinization), higher susceptibility to subacute acidosis, and higher costs of production.

Effects of feeding combinations of steam-flaked grain sorghum and steam-flaked, high-moisture, or dry-rolled corn on growth performance and carcass characteristics in feedlot cattle.

The objective of these two feeding trials was to determine the associative effects of feeding steam-flaked grain sorghum (SFGS) in combination with steam-flaked (SFC), dry-rolled (DRC), or high-moisture (HMC) corn on growth performance and carcass characteristics in feedlot cattle. In Trial 1, 200 yearling heifers were blocked by weight, allotted to 25 pens, and fed one of five finishing diets (77% grain, 15% corn silage, and 8% supplement on a DM basis) for an average of 137 d. The grain combinations were 100:0, 75:25, 50:50, 25:75, and 0:100 SFC:SFGS, respectively. Treatment had no effect on DMI (P > .05), but ADG, gain efficiency, and final live and hot carcass weights decreased linearly (P < .05) as the proportion of SFGS increased in the diet. Carcass backfat, quality grade, and liver abscess score were not affected (P > .05) by treatment. In Trial 2, 306 yearling steers were blocked by weight, allotted to 30 pens, and fed diets that contained 74.5% grain, 10% corn silage, 7.5% soybean meal, 4% tallow, and 4% supplement (DM basis) for an average of 139 d. The grain and grain combinations were 100% DRC, HMC, SFC, or SFGS and a 67%:33% combination of SFGS: DRC or SFGS:HMC. For steers fed diets containing a single source of grain, those fed SFC gained 7% more live weight and had a 7% higher gain efficiency (P < .05) than those fed DRC or HMC. Growth performance of steers fed SFGS was intermediate. Feeding grain combinations (67% SFGS:33% HMC or DRC) resulted in a 5 to 6% positive associative effect (P < .05) for ADG and gain efficiency. Carcass characteristics were not affected (P > .05) by treatment. We concluded that there were significant benefits (positive associative effects) when SFGS was fed in combination with DRC or HMC, but the effects were smaller when SFGS was fed in combination with SFC.

Flake density of steam-processed sorghum grain alters performance and sites of digestibility by growing-finishing steers.

The effect of several flake densities (FD) of steam-processed sorghum grain on performance, and site and extent of nutrient digestibilities by steers fed growing and finishing diets was determined. The effectiveness of common laboratory methods of starch availability (enzymatic hydrolysis or gelatinization) to provide target specifications for quality control of steam-flaked grains was also measured. In vitro starch availability of the processed grains increased (P < .05) linearly in response to decreased FD. Flake density was more highly correlated with enzymatic measures than with percentage gelatinization (R2 = .87 to .93 vs .36). Using 140 crossbred beef steers (181 kg initial weight), feedlot performance was determined for 112 d with a growing diet (50% grain), followed by 119 d with a finishing diet (78% grain). Each FD treatment (412, 360, 309, and 257 g/L or 32, 28, 24, and 20 lb/bu) was randomly assigned to five pens of seven steers each. Intake of DM by steers decreased linearly (P < .05) as FD decreased (7 and 13%, respectively, for growing and finishing diets). Decreasing FD reduced linearly (P < .05) ADG in the finishing phase and for the entire 231-d trial. With the growing diet only, feed efficiency and estimated diet NEm and NEg responses to decreasing FD were curvilinear (P < .05), with the 360 g/L (28 lb/bu) flake being most efficient. Electrical energy requirements for processing increased linearly (P < .05) as FD decreased. Using four multi-cannulated crossbred steers (275 kg), starch digestibility increased linearly (P < .05) in the rumen (82 to 91%) and total tract (98.2 to 99.2%) as FD decreased. Digestibilities within the small (74%) and large intestines (62%) were not altered by FD. Decreasing FD increased (P < .05) total CP digestibility, but did not consistently alter fiber digestibility or DE content of the diets. In conclusion, enzymatic laboratory methods to evaluate starch availability in processed grains can be used satisfactorily to establish FD criteria for quality control of the steam-flaking process. The greatest improvements in efficiency, estimated diet NE, and starch and protein digestibilities usually occurred when FD was decreased from 412 to 360 g/L (32 to 28 lb/bu). Based on these measures and processing costs, the optimal FD was 360 g/L (28 lb/bu).

Modified angström exponent for the characterization of submicrometer aerosols.

The classical Angström exponent is an operationally robust optical parameter that contains size information on all optically active aerosols in the field of view of a sunphotometer. Assuming that the optical effects of a typical (radius) size distribution can be approximated by separate submicrometer and supermicrometer components, we show that one can exploit the spectral curvature information in the measured optical depth to permit a direct estimation of a fine-mode (submicrometer) Angström exponent (alpha(f)) as well as the optical fraction of fine-mode particles (eta). Simple expressions that enable the estimation of these parameters are presented and tested by use of simulations and measurements.

Decision analysis applied to the purchase of frozen premixed intravenous admixtures.

A structured decision-analysis model was used to evaluate frozen premixed cefazolin admixtures. Decision analysis is a process of stating the desired outcome, establishing and weighting evaluation criteria, identifying options for reaching the outcome, evaluating and numerically ranking each option for each criterion, multiplying the ranking by the weight for each criterion, and calculating total points for each option. It was used to compare objectively frozen premixed cefazolin admixtures with batch reconstitution from vials and reconstitution of lyophilized, ready-to-mix containers. In this institution the model numerically demonstrated a distinct preference for the premixed frozen admixture over these other alternatives. A comparison of these results with the total cost impact of each option resulted in a decision to purchase the frozen premixed solution. The advantages of the frozen premixed solution that contributed most to this decision were decreased waste and personnel time. The latter was especially important since it allowed for the reallocation of personnel resources to other potentially cost-reducing clinical functions. Decision analysis proved to be an effective tool for formalizing the process of selecting among various alternatives to reach a desired outcome in this hospital pharmacy.

Stimulation of proliferation and inhibition of function of xenotransplanted human thyroid tissue by epidermal growth factor.

A stimulation of thyroid epithelial cell proliferation by epidermal growth factor (EGF) has been repeatedly reported in different in vitro systems. Furthermore, a suppression of thyroid epithelial cell function by EGF has been described in vitro. In order to investigate the effects of EGF on the thyroid in vivo, human Graves' disease tissue was transplanted to 59 nu/nu mice. EGF was given once, and over a period of 7 days 7 times intermittently or continuously by osmotic mini pumps to mice. 3-H-thymidine histoautoradiography of transplants showed an increased 3-H-thymidine incorporation of thyroid epithelial cells and mesenchymal cells, following each form of EGF application. Thyroid epithelial cell nuclear volume, which has previously been shown to be a parameter for thyroid epithelial cell function showed a decrease following EGF application. There was a tendency to a more intensive proliferation and differentiation following intermittent EGF application compared to continuous stimulation. These results demonstrate that EGF does stimulate proliferation of thyroid epithelial as well as mesenchymal cells in vivo. The growth stimulating effect of EGF is linked with a concomitant decrease of thyroid function in vivo. The latter is most likely due to the dedifferentiating action of EGF previously shown in in vitro systems.

Interdisciplinary committee on infusion-control devices: containing related-product costs.

A program for decreasing expenditures for i.v. sets and related items at a 530-bed university teaching hospital is described. A multidisciplinary committee originally formed to evaluate infusion-control devices (ICDs) developed a cost-containment strategy for reducing the number of accessories and amount of equipment used in i.v. therapy and for reducing inappropriate use of these items. Major problems identified in an audit were excessive use of secondary sets; inappropriate use of add-on flow-control devices, extension sets, and metered-chamber sets; and use of the wrong type of i.v. set with ICDs. New procedural guidelines, inservice-education programs, evaluation of new and different i.v. products, and increased enforcement of policies and procedures by the pharmacy department were implemented to address these problems. For fiscal year 1986, the bid process for i.v. equipment was divided into 10 sections so that manufacturers who may not have been able to bid on every item could bid only on individual sections if they desired. A follow-up audit six months after implementation of the strategy showed increased compliance with guidelines for use of i.v. sets and devices. Compared with the previous year, data for fiscal year 1986 showed total savings of $142,223 attributable to decreased use of i.v. equipment. The competitive-bid process saved $54,942; the total amount saved was $197,165. The trend of appropriate use as a result of adherence to the guidelines continued through fiscal year 1987. This multidisciplinary cost-containment approach was effective in reducing expenditures for i.v. sets and equipment.

Interdisciplinary committee on infusion-control devices: evaluating new products.

Evaluation and selection of volumetric infusion-control devices (ICDs) by an interdisciplinary committee in a university teaching hospital is described. The committee, which was originally formed to evaluate problems with the existing system of ICD management, determined that the ICDs in use at the hospital were outdated. After gathering information on the types of ICDs available and identifying options for replacing the existing equipment, the committee decided to replace some of the devices with new volumetric ICDs. A six-page evaluation form was mailed to ICD manufacturers, and representatives from 16 manufacturers were invited to demonstrate their devices to the committee members. Five manufacturers were then invited to participate in a two-week, inhouse comparative trial, during which the devices were objectively evaluated by nurses, the bioinstrumentation department, and the ICD committee. The results of that evaluation were used to construct bid specifications. The decision of which ICDs to purchase was based on cost factors and the degree to which the devices met the specifications. The use of a multidisciplinary committee to evaluate and select new ICDs was an effective strategy. The devices that were purchased represented improvements in patient safety and cost-effectiveness.

Microcost analysis of the prescription dispensing process in an outpatient hospital pharmacy.

The costs involved in dispensing a prescription in an outpatient pharmacy at a 450-bed teaching hospital were studied. Work sampling was used to determine pharmacist and technician time involved in dispensing a prescription, and other direct and indirect costs involved in dispensing a prescription were isolated. The cost per prescription was calculated as the total of personnel costs for dispensing plus other costs, excluding the cost of the drug. Average of 2.68 and 3.37 minutes of pharmacist and technician time, respectively, were directly involved in dispensing each prescription. The standard auxiliary times per prescription were calculated to be 1.17 minutes and 4.66 minutes for the two groups, respectively. Total pharmacy personnel time consumed in dispensing a prescription was 13.33 minutes. Total calculated personnel cost included in dispensing a prescription was +3.14. Adding to this figure other direct and indirect costs resulted in a total cost of +5.42 for dispensing a prescription. Although the time and cost figures identified are unique to this outpatient pharmacy, other institutions can use these microcosting techniques to provide data that can be useful in the negotiation of contracts for the provision of pharmaceutical services to ambulatory patients.

Regional stimulation of thyroid epithelial cells in Graves' disease by lymphocytic aggregates and plasma cells.

The significance of intrathyroidal lymphocytic infiltration is not known. However, several indirect lines of evidence suggest that interstitial or intraepithelial lymphocytes are the effector or thyroid autoantibody-producing lymphocytes in Graves' disease. This has not been investigated in vivo. Changes of nuclear volume of endocrine cells have previously been shown to be a reliable parameter of functional stimulation of endocrine glands. Therefore we investigated this parameter near and off lymphocytic aggregates, loosely distributed plasma cells and memory T cells in paraffin sections of Graves' disease thyroid glands. In 21 Graves' disease thyroid glands we found significant increases of thyroid epithelial cell nuclear volume near plasma cells (198.4 micron3) as well as near lymphocytic aggregates (219.1 micron3) compared with thyroid epithelial cell nuclear volume one microscopic field away (160.1 and 137.7 micron3 respectively). Similar nuclear volume differences were observed after propanolol and thiourelene antithyroid drug treatment. These nuclear volume differences could not be observed in 10 control thyroid glands and around CD45R0-positive memory T cells in Graves' disease thyroid glands. These direct in vivo investigations of regional functional stimulation of thyroid epithelial cells in Graves' disease show local stimulation near lymphocytic aggregates and diffusely distributed plasma cells. Therefore our in vivo data do not permit to identify stimulatory lymphocytes only interstitially or intraepithelially as previously suggested.

[Peripheral nerve injury due to total replacement of the hip-joint (author's transl)]. / Läsionen peripherer Nerven bei totalem Hüftgelenkersatz

Report on peripheral nerve lesions due to total replacement of the hip-joint based on the literature and the authors' own experience. In 15 patients our diagnosis was made on clinical and electromyographic evidence. 16 endoprostheses had been inserted. The femoral nerve was involved on 12 occasions, the sciatic in 5, the glutei in 5, the obturator in 2, the lateral cutaneous femoris in 2 and the posterior cutaneous in 1 instances. One has to count on about 1% of such lesions. This type of paresis has to be distingushed from pseudopareses for which electromyography was proved very effective. Damage due to overstretching is probably the main cause. Treatment with thorough physiotherapy and faradic stimulation is needed. When this is done the prognosis is generally favourable. In some cases, however, these complications may limit the success of the operation and postoperative disability may be worse than before.

[Nerve lesions following total hip replacement and other hip-joint operations]. / Nervenläsionen beim totalen Hüftgelenkersatz und anderen Operationen am Hüftgelenk

Nerve lesions occurred in 17 patients who had undergone hip-joint operations (especially total replacement). The femoral nerve was most commonly affected, followed by sciatic and gluteal nerves, with combined pareses in six. As differential diagnosis from pseudoparesis is not always possible, electromyography should be performed in all cases. Stretching and/or squeezing are the most important causes. The operation results are significantly impaired by such nerve lesions. However, long-term results are usually satisfactory in the majority of cases. Early diagnosis and treatment are important in ensuring good therapeutic results.