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Objective: This study aimed to compute the pooled prevalence of diabetes mellitus and other underlying conditions in patients with coronavirus disease 2019 associated rhino-orbito-cerebral mucormycosis. Method: A systematic literature review was performed in PubMed, Scopus, Web of Science, Embase and Google Scholar. The cross-sectional studies that reported the frequency of diabetes mellitus in patients with coronavirus disease 2019 associated rhino-orbito-cerebral mucormycosis were included. Results: Eighteen eligible studies with a total number of 3718 patients were included in the current study. The pooled prevalence of diabetes in patients with coronavirus disease 2019 associated rhino-orbito-cerebral mucormycosis was 89 per cent and with new-onset diabetes was 32 per cent. The pooled prevalence of steroid use was high (79 per cent) too. The all-cause mortality rate was 24 per cent. Conclusion: Diabetes mellitus was the most frequent underlying condition in patients with coronavirus disease 2019 associated rhino-orbito-cerebral mucormycosis. The second most frequent underlying condition was steroid use during coronavirus disease 2019 infection. The appropriate control of hyperglycaemia and rational prescription of steroids during the treatment of coronavirus disease 2019 associated rhino-orbito-cerebral mucormycosis is recommended. [ABSTRACT FROM AUTHOR]

Surface grinding is one of the most extensively used procedures in industry for finishing materials. Different machining parameters have a great impact on a product's surface quality. While processing temperature increases and heat energy is generated, that may cause a few changes in the tool or work piece in chemical and physical properties. This will have an effect on the final product surface. Furthermore, numerous aspects of the machine, such as vibration, degree of freedom, and precise size, have an impact on the quality of the surface finish. The machining parameters, on the other hand, have a major role in determining the surface finish. The functional behavior of machined components can be enhanced by the grinding process, so proper selection of grinding wheel specifications and grinding parameters can result in improving the surface integrity. Because of this, understanding the surface integrity imparted by grinding is very important. This paper will display the results of an experimental study that were conducted to comprehensively investigate the effect of surface grinding input machining parameters on the formed surface quality. The experiments are running by changing the input machine parameters which are the feed rate, cutting speed, cooling method and depth of cut. The surface roughness and the cutting forces are the performance to be measured and assessed. It is concluded that the surface roughness (Ra) decreases with the increase in cutting speed and the coolant flow rate. But, as the feed rate and or the depth of cut increase the surface roughness (Ra) will also increase. The results of this investigation can be used to determine the optimal process parameters in order to obtain the required roughness quality of the produced surface in grinding of (ASTM A36) mild carbon steel. [ABSTRACT FROM AUTHOR]

The study was carried out to study the effect of the infestation by Myzus persicae (Sulzer) (Hemiptera: Aphididae) and Tetranychus urticae Koch (Acari: Tetranychidae) on the internal components of Aloe barbadensis (Miller), the common name Aloe Vera cactus which belong to (Fam. Liliaceae). Experiments were carried out at two locations (governorates), Al- Orman garden (Giza Governorate) and The international garden (Alexandria Governorate) during season 2021. Obtained results showed that the infestation by M. persicae and T. urticae reduced the concentration of the internal components of Aloe Vera leaves such as Vitamin A, Vitamin C, Vitamin E, Vitamin B12, Folic acid, Amino acids, Salicylic acids, Minerals, Sugars, Lignin, Saponins and Beta carotene. And obtained results showed also that the effect of the infestation by M. persicae was higher than the effect of the infestation by T. urticae compared to control (Aloe Vera plants which did not infest by any pests) at the two tested locations. Statistical analysis showed that were highly significant differences between concentrations of the internal components of the infested Aloe Vera cactus plants with the two tested pests compared to the concentration of the same components in the control (non-infested cactus plants). [ABSTRACT FROM AUTHOR]

This study was carried out to study the effect of the insect infestation by The Green Peach Aphid, Myzus persicae (Sulzer) (Hemiptera: Aphididae) and The Greenhouse Whitefly, Trialeurodes vaporariorum (Westwood) (Homoptera: Aleyrodidae) on the quantity of the annual production of the strawberry crop, Fragaria ananassa (L.). This study was carried out at Tokh region (Qaliobya Governorate) during two successive seasons 2020, 2021 under glasshouse conditions. This study was divided into three parts, first part studied the population fluctuation of M. persicae and T. vaporariorum on strawberry plants during the two successive seasons, second part studied the effect of insect infestation by the two insects on the quantity of the annual production of strawberry fruits at the two successive seasons compared to control (which did not infest with any insect) and third part studied the effect of insect infestation by the two insects on the internal components of strawberry fruits. Results obtained showed that the infestation by M. persicae and T. vaporariorum reduced the quantity of annual production of strawberry fruits compared to control (which was non-infested by the same insects). Also, results obtained showed that the infestation by the same insects reduced both total sugar and total protein on strawberry fruits compared to control. [ABSTRACT FROM AUTHOR]

In this paper, a linear two degrees of freedom linear bicycle model is proposed to investigate the vehicle handling criterion. The study is based on simulation developed using MATLAB / Simulink to predict the vehicle dynamic stability. Steering angle is given as an input to the mathematical model for various vehicular manoeuvres. This model is validated using a step input which is adjusted to give 0.3g lateral acceleration. The system model is simulated under a typical front wheel steering to examine the highway vehicle prediction output within its manoeuvre. This input is also adjusted to keep lateral acceleration value in steady state region. It is found that changing the vehicle center of gravity (CG) position, vehicle mass, tire cornering stiffness and vehicle speed all have a significant influence on the vehicle dynamic stability. [ABSTRACT FROM AUTHOR]

A considerable amount of vibration energy in automotive is worth of being harvested through power dissipation using regenerative suspension systems. In this study, the vehicle dynamics and energy dissipated from a Multi-State Switchable Damper (MSSD) based suspension for various vibration dynamic modes are assessed. Quantification of the energy dissipated in a MSSD is achieved through an experimental test at laboratory environment. The test results showed a linear relationship between the dissipated power and the damping modes. [ABSTRACT FROM AUTHOR]

A considerable amount of vibration energy in automotive is worth of being harvested through power dissipation using regenerative suspension systems. In this study, the vehicle dynamics and energy dissipated from a Multi-State Switchable Damper (MSSD) based suspension for various vibration dynamic modes are assessed. Quantification of the energy dissipated in a MSSD is achieved through an experimental test at laboratory environment. The test results showed a linear relationship between the dissipated power and the damping modes. [ABSTRACT FROM AUTHOR]

Fibrous reinforcements for structural composites manufacturing need to undergo in certain cases a complex shape forming process during which multiple defects could appear. These defects, such as tow buckling and tow sliding may reduce the integrity of the final part. The onset of these defects depends on the initial loading conditions, the shape of the preform and the characteristics of the textile material. While mechanisms behind the formation and development of both defects are yet to be fully understood. We focused, in this work, on investigating the buckling defect. In order to do so, we used optical field measurement techniques to monitor the kinematics of the defect appearance and predict it via an adapted analytical model of the defect appearance. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Animal & Poultry Production is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Animal & Poultry Production is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The inhibiting impact of natural aqueous extracts of some plants such as curcumin, parsley and cassia bark extracts for the corrosion of carbon steel (C-steel) in 0.5 M H2SO4 solution was inspected utilizing some techniques such as galvanostatic and potentiodynamic anodic polarization and weight loss measurements. Outcomes indicated that the percentage inhibition efficiency increases with increasing the concentration of the extract due to its horizontal adsorption on the C-steel surface. The process of adsorption is followed by the Temkin isotherm. These natural extracts acted as pitting corrosion inhibitors by shifting the pitting potential to more noble values. The sequence of inhibition efficiency of the natural extracts decreases in the following order: cassia bark extract > parsley extract > curcumin extract. This arrangement is related to the molecular size of the major components of the three natural extracts used. [ABSTRACT FROM AUTHOR]

Presents information on a study which investigated the properties of electron and hole traps present in n-type GaAs[sub1-x]P[subx] alloys and their evolution versus the alloy composition through deep-level transient spectroscopy. Determination of the ionization energies of electron and hole traps; Discussion; Conclusion.

The structural and magnetic properties of amorphous ferromagnetic microwires can undergo significant measurements under the action of external mechanical stresses and heat treatment. The study of transformations occurring in this case is important for designing various sensors of mechanical stresses, loading, and temperature and also for inducing in the wires a certain type of magnetic anisotropy that plays a significant role in the realization of various effects in them. In this work, the influence of external stresses and annealing on the processes of the magnetization and the magnetic impedance of Co71Fe5B11Si10Cr3 microwires having a low positive magnetostriction (~10-8) in amorphous state has been studied. The influence of external stresses leads to a sharp change in the character of the magnetization reversal curve, which was due to the change in the sign of the magnetostriction and the type of magnetic anisotropy. The amplitude of higher harmonics and the value of the magnetic impedance, respectively, are sensitive to mechanical stresses. Elastic stresses in the wires with a partial crystallization do not lead to a marked change in the magnetic properties; however, annealing can lead to a substantial increase in the axial magnetic anisotropy of the wires existing in the stressed state. The experimental results are analyzed in the framework of a magnetostriction model of induced magnetic anisotropy. [ABSTRACT FROM AUTHOR]

Various thermal treatments have long been known to be effective in tailoring structural and magnetic properties of amorphous ferromagnetic wires, consequently, a desired magnetic anisotropy can be controlled for specific sensing applications. This paper deals with the effects of annealing and applied stresses on the magnetization processes and magnetoimpedance (MI) in Co71Fe5B11Si10Cr3 glass-coated microwires having amorphous or partially crystalline structure. The alloy under study has a small positive magnetostriction (approximately 10^-8 ) in its amorphous unstressed state. By applying a tensile stress to amorphous microwires, an abrupt transformation of the hysteresis loop is observed owing to the anisotropy type change due to stress-dependent magnetostriction which changes sign. The modification in the anisotropy type greatly enhances the stress sensitivity of higher frequency harmonics induced during re-magnetization and MI. The wires with a partially crystalline structure did not exhibit a noticeable stress dependence of magnetic properties, but after annealing a significant increase in coercivity was observed after applying a tensile stress. The obtained results were investigated in terms of a magnetostrictive model of magnetic anisotropy offering a reasonable explanation. [ABSTRACT FROM AUTHOR]

The present taxonomic revision of the family Malachidae (Genera: Attalus, attalusinus, brachyattalus, Callotroglops, Cephalonicus, Clanoptilus, Ebaeus and Hypebaeinais basedmainly on the materials, represented in the main reference insect collections in Egypt and/or materials collected during the field survey. Diagnostic characters of the genera and species based on the external morphological characters of the adults. Synonyms, taxonomical notes, local and world distribution of each species are provided. [ABSTRACT FROM AUTHOR]

A checklist of the family Megachilidaeas existing in Egypt is given, based on material kept in the main reference insect collections in Egypt and records in the literature. The list includes 102 species and 6 subspecies belonging to 9 genera of 5 tribes (Anthidini, Fidelini, Lithorgini, Megachilini, and Osmini) under two subfamilies (Fidelinae and Megachilinae), of which 84 species of seven genera and the six subspecies are insect pollinators, and 18 species of two genera are cleptoparasities. Updated scientific names and synonyms are presented together with taxonomic notes on host records and distribution for most species in Egypt. All taxa (subfamilies, tribes, genera and species are alphabetically arranged. [ABSTRACT FROM AUTHOR]

An updated checklistof the Egyptian species of the family Tenebrionidae (Coleoptera) is presented. The listincludes about 397 species belonging to 5 subfamilies in 33 tribesbased on the records in literatures and material kept in the main reference insect collections of Egypt. Synonyms of some species and the recent taxonomic position are included. The taxa (subfamilies, tribes, genera and species) are arranged in alphabetical order. [ABSTRACT FROM AUTHOR]

Domiati cheese was made from reconstituted milk (20% total solids) containing normal (C) and high level (T) of conjugated linoleic acid (CLA) content respectively using mixed probiotic Lactobacillus casei and Enterococcus fecium (1:1) as starter. The cheeses were stored in brine at 25±5°C for 60 d storage. The added probiotics grow equally well in C and T cheeses. The total viable and Lb casie counts increased to a maximum after 15 d of storage and then decreased while the counts of Enterococcus fecium and total lactic acid continued to increase until the end of the storage period. The cheeses retained high counts of these probiotics (>l07 cfu g-1) throughout the storage period. The acidity, soluble nitrogen, free amino acid, and conjugated dienes increased significantly in Domiati cheese during storage with small differences between treatments except for the significantly higher conjugated dienes in T than C treatment. [ABSTRACT FROM AUTHOR]

A pot experiment was conducted to evaluate the influence of certain oil-seed cakes i.e. fennel, sesame, anise or plant dry seed powder of red pepper as soil amendments in comparison with oxamyl or urea on controlling Meloidogyne incognita infecting eggplant seedlings under greenhouse conditions at 27 ± 5°C. Results indicated that all tested materials significantly improved the growth of eggplant and suppressing the number of galls, females and egg masses of M. incognita as compared to nematode alone. Moreover, anise oil-cake gave the best growth of total plant fresh and dry shoot weights as percentage increase (160.8 and 64%) followed by sesame oil-cake (143.5 and 64%), respectively. However, the highest values of percentage reduction for number of galls (64.2%), females (58.5%) and egg masses (55.7%) on eggplant roots were achieved by sesame-oil-cake application, followed by anise-oil-cake treatment with values of 63.0, 59.6 and 51.1% for the same nematode criteria, respectively. Meanwhile, oxamyl or urea treatment showed remarkable reduction percentages for nematode parameters tested. [ABSTRACT FROM AUTHOR]

This study looked at echocardiographic predictors of left ventricular outflow obstruction after primary neonatal repair of interrupted aortic arch and ventricular septal defect. Results of this study indicate that the only significant independent predictor of left ventricular outflow obstruction is aortic valve diameter; all patients with an aortic valve diameter <4.5 mm (Z score <-5) subsequently developed obstruction, whereas patients with annuli >4.5 mm (Z score >-5) remained free from obstruction. [ABSTRACT FROM AUTHOR]

Background and Purpose: Flow diversion has gradually become a standard treatment for intracranial aneurysms of the anterior circulation. Recently, the off-label use of the flow diverters to treat posterior circulation aneurysms has also increased despite initial concerns of rupture and the suboptimal results. This study aimed to explore the change in complication rates and treatment outcomes across time for posterior circulation aneurysms treated using flow diversion and to further evaluate the mechanisms and variables that could potentially explain the change and outcomes., Materials and Methods: A retrospective review using a standardized data set at multiple international academic institutions was performed to identify patients with ruptured and unruptured posterior circulation aneurysms treated with flow diversion during a decade spanning January 2011 to January 2020. This period was then categorized into 4 intervals., Results: A total of 378 procedures were performed during the study period. Across time, there was an increasing tendency to treat more vertebral artery and fewer large vertebrobasilar aneurysms ( P = .05). Moreover, interventionalists have been increasingly using fewer overlapping flow diverters per aneurysm ( P = .07). There was a trend toward a decrease in the rate of thromboembolic complications from 15.8% in 2011-13 to 8.9% in 2018-19 ( P = .34)., Conclusions: This multicenter experience revealed a trend toward treating fewer basilar aneurysms, smaller aneurysms, and increased usage of a single flow diverter, leading to a decrease in the rate of thromboembolic and hemorrhagic complications., (© 2022 by American Journal of Neuroradiology.)

Background: The underlying mechanism of action of flow diverters is believed to be the induction of aneurysm thrombosis and simultaneous endothelial cell growth along the device struts, thereby facilitating aneurysm exclusion from the circulation. Although extensive attention has been paid to the role of altered cerebrovascular hemodynamics using computational fluid dynamics analyses, relatively less emphasis has been placed on the role of the vascular endothelium in promoting aneurysm healing., Purpose: Our aim was to systematically review all available literature investigating the mechanism of action of flow diverters in both human patients and preclinical models., Data Sources: A systematic search of PubMed, Cochrane Central Register of Controlled Trials MEDLINE, EMBASE, and the Web of Science electronic data bases was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines., Study Selection: We selected articles assessing the role of endothelialization in flow-diverter treatment of cerebral aneurysms, including both preclinical and clinical studies., Data Analysis: Ten articles were eligible for inclusion in this review. Two assessed endothelialization in human patients, while the other 8 used preclinical models (either rabbits or pigs)., Data Synthesis: Methods used to assess endothelialization included optical coherence tomography and scanning electron microscopy., Limitations: A limitation was the heterogeneity of studies., Conclusions: Current data regarding the temporal relationship to flow-diverter placement has largely been derived from work in preclinical animal models. Whether these cells along the device struts originate from adjacent endothelial cells or are the result of homing of circulating endothelial progenitor cells is equivocal., (© 2019 by American Journal of Neuroradiology.)

Vitiligo occurs in Northern Europe in one of 200 people. The disease can cause significant psychological stress for the affected individual. These patients generate and accumulate massive amounts of H(2)O(2)- and peroxynitrite in the epidermal compartment. Consequently many proteins are oxidized or nitrated, leading in turn to partial or complete loss of functionality. Moreover, presence of DNA damage in the skin as well as in plasma has been shown, while apoptosis is not enhanced. Induction of DNA repair is associated with up-regulated functioning p53 protein. Considering possible genetic predisposition and /or spontaneous mutations, autoimmune reactions in the disease are put forward in the context of oxidative stress. In addition a review of recent and novel treatment modalities including the role of oxidative stress reduction and combined climatotherapy at the Dead Sea in a group are discussed.

Background: Symptomatic cholelithiasis occurs in pregnancy in our patient population, some of whom are diabetic. But its management remains controversial. How common is the problem? Is our current policy of management appropriate for our patients?, Patients and Methods: The management of 162 pregnant patients admitted over a ten-year period with symptomatic cholelithiasis was evaluated in a retrospective study. The patients were divided into two groups: Group A, 58 patients with diabetes mellitus, and Group B, 104 nondiabetic patients., Results: Symptomatic cholelithiasis occurred in only 0.3% of our pregnant patients. Of 162 patients, 148 (91.4%) had successful conservative (nonsurgical) management. There was no fetal loss, premature birth, maternal morbidity or mortality. Fourteen patients who had failure of conservative treatment had surgical management. When the postpartum cholecystectomy hospitalization days were added to the total days of admission for the nonoperative cases, there was a significant difference in the mean total number of days of hospitalizations between the surgical cases, 12.4 days, and the nonsurgical cases, 20.5 days (P<0.001), but not in the mean number of hospitalizations, 2.3 versus 3.3., Conclusion: Our current policy of conservative management seems optimal. It has, however, been achieved at the price per patient of 8 extra days of hospitalization. In keeping with recent improvements in surgery and the advent of laparoscopic surgery, a more cost-efficient approach would suggest a more aggressive policy.

Hypertension is common in the hemodialysis population. Although hypertension in the general population has been shown to reduce survival and to accelerate atherosclerosis, leading to serious cardiac and cerebrovascular morbidity, its effects are less clear in those undergoing dialysis. This review focuses on recent studies showing a favorable outcome in hypertensive hemodialysis patients when compared with those with lower blood pressure. The possible explanations for this paradoxic relationship are examined, and practical suggestions are given for the management of hypertension in the patient undergoing hemodialysis. We also present information on the morbiditiy associated with hypertension in the hemodialysis population.

Atrial natriuretic peptide (ANP), an endogenous hormone synthesized by the cardiac atria, has been shown to improve renal function in multiple animal models of acute renal failure. In a recent multicenter clinical trial of 504 patients with acute tubular necrosis (oliguric and nonoliguric), ANP decreased the need for dialysis only in the oliguric patients. In the present study, 222 patients with oliguric acute renal failure were enrolled into a multicenter, randomized, double-blind, placebo-controlled trial designed to assess prospectively the safety and efficacy of ANP compared with placebo. Subjects were randomized to treatment with a 24-hour infusion of ANP (anaritide, 0.2 microgram/kg/min; synthetic form of human ANP) or placebo. Dialysis and mortality status were followed up for 60 days. The primary efficacy end point was dialysis-free survival through day 21. Dialysis-free survival rates were 21% in the ANP group and 15% in the placebo group (P = 0.22). By day 14 of the study, 64% and 77% of the ANP and placebo groups had undergone dialysis, respectively (P = 0.054), and 9 additional patients (7 patients, ANP group; 2 patients, placebo group) needed dialysis but did not receive it. Although a trend was present, there was no statistically significant beneficial effect of ANP in dialysis-free survival or reduction in dialysis in these subjects with oliguric acute renal failure. Mortality rates through day 60 were 60% versus 56% in the ANP and placebo groups, respectively (P = 0.541). One hundred two of 108 (95%) versus 63 of 114 (55%) patients in the ANP and placebo groups had systolic blood pressures less than 90 mm Hg during the study-drug infusion (P < 0.001). The maximal absolute decrease in systolic blood pressure was significantly greater in the anaritide group than placebo group (33.6 versus 23.9 mm Hg; P < 0.001). This well-characterized population with oliguric acute renal failure had an overall high morbidity and mortality.

Background: Few studies have quantified the effect of hypertension on survival in the haemodialysis (HD) population. We have previously reported lack of adverse effect of hypertension on 1-year mortality in a cohort of 649 haemodialysis patients (Am J Kidney Dis 1996; 28: 737-744). We report here the effect of hypertension on 2-year survival in the same cohort of patients., Methods: We reviewed the complete computerized files on 649 HD patients enrolled in 10 haemodialysis centres in the state of Mississippi, USA. One-month dialysis records for each patient from mid-October 1994 to mid-November 1994 were reviewed. Predialysis mean arterial pressure was calculated as immediate predialysis diastolic pressure plus one-third the difference between systolic and diastolic pressure. Patients were classified as hypertensive if their average pre-MAP was more than 114 mmHg or they were receiving antihypertensive drugs during the study period. Normotensives had a pre-MAP < 114 and were not receiving any antihypertensives. We followed these patients for 2 years to determine their survival and the effect of their BP status, as determined in October 1994, on 2-year mortality., Results: In univariate analysis, hypertension was associated with improved 2-years survival (relative risk 0.64, P=0.08 compared to normotensives). Furthermore, among the hypertensives, good blood pressure control (less than 140/90) was associated with increased relative risk of death at 2 years (RR 1.86, P=0.004). In multivariate analysis, taking age, race, serum albumin, and diabetic status into consideration, there was a 27% reduction in mortality among hypertensives compared to normtensives (RR 0.73, P=0.06). Other factors of significance in multivariate analysis were age (RR 1.03/year, P=0.02), serum albumin (RR 0.36/g, P<0.0001), diabetes mellitus (RR 1.35, P=0.07), and race (RR 0.64, P=0.05)., Conclusions: Our study suggests that hypertension has no adverse effect on survival at 2 years in the haemodialysis population.

For abdominal hernia 982 patients were operated. The complications had occurred in 18.6% of patients due to chronic inflammation and the presence of "sleeping" infection in the hiatal gates margins. Application of the elaborated prophylaxis complex of measures had permitted to lower the frequency of the wound healing complications down to 9%.

The initial 300 patients whose symptomatic cholelithiasis was managed by laparoscopic cholecystectomy (LC) were matched to and compared with 300 patients managed by open cholecystectomy (OC) during the 30 months prior to the introduction of LC. Of the 300 LC attempted 292 (97.3%) were successful with conversion to OC rate of 2.7%. Besides the obviously better cosmetic results, LC patients had less post operative pain, mean doses of opiates needed 0.01 versus 5 for OC (p < 0.0001), were discharged earlier from the hospital, mean 3.1 days versus 8 days for OC (p < 0.001) and had less postoperative complications 4% versus 11% for OC. We conclude that not only is LC a better operation than OC, but also that in the regional referral centres such as ours, LC can safely supplant OC as the preferred modality for the management of symptomatic cholelithiasis.

There are no epidemiologic studies documenting the prevalence of hyperparathyroidism in the US hemodialysis population. We looked at a random sample of 612 hemodialysis patients enrolled in 10 outpatient dialysis units in Mississippi. Fifty percent of the patients surveyed had an intact serum parathyroid hormone (PTH) level more than three times normal (mean, 622 pg/mL). Another 25% had a less than normal PTH level (mean, 33 pg/mL), suggesting adynamic bone disease. Abnormal serum calcium was also common. Seventeen percent of patients were hypocalcemic and 14% were hypercalcemic. These high point prevalences occurred despite widespread use of calcium supplements and/or vitamin D (used in 90% of the patients surveyed). Black patients tended to have a lower serum calcium and higher PTH level than white patients. We also found that diabetic patients are less likely to have an elevated PTH level than nondiabetic patients. Elevated serum phosphorus was the most important factor correlating with the development of secondary hyperparathyroidism. Causes of inadequate control of hyperparathyroidism in this population require further study.

Excess volume is thought to be the major mechanism leading to hypertension in the hemodialysis population. Blood pressure measurements and volume parameters were obtained in 434 hemodialysis patients in 1994 and compared to their 1993 data. Equal numbers of patients were receiving antihypertensive treatment in both 1993 and 1994. The predialysis mean arterial pressure (pre-MAP) did not significantly change after 1 year of dialysis. The lack of change in blood pressure was evident in those who either lost or maintained body weight. There was no correlation between changes in interdialytic weight and changes in pre-MAP over 1 year. Volume sensitivity (described as the percentage decrease in blood pressure immediately after dialysis) was not different in 1993 from 1994. We conclude that irrespective of weight changes, the average hemodialysis patient does not show a significant change in blood pressure (BP) after 1 year of dialysis. This lack of improvement was evident regardless of age, sex, race, dialysis duration, or etiology of end-stage renal disease.

Ethylene glycol poisoning is a rare yet potentially fatal illness seen most commonly in association with ingestion by alcoholics or in suicide attempts. It is characterized by an elevated anion gap metabolic acidosis, osmolal gap, calcium oxalate crystals in the urine, and a well-defined clinical picture. Prompt treatment is crucial because effective intervention can prevent the neurologic, cardiac, pulmonary, and renal sequelae associated with ethylene glycol poisoning. Hemodialysis offers rapid clearance of ethylene glycol and its toxic metabolites. In this article, the case of a hemodialysis patient who suffered contamination of the dialysate solution with ethylene glycol, leading to altered mental status, coma, and severe anion gap metabolic acidosis, is reported. Despite prolonged dialysis and correction of the acidosis, the patient remained comatose and subsequently died.

Few studies have quantified the effect of hypertension on survival in the hemodialysis population. We report the effect of hypertension on 1-year survival in 649 hemodialysis patients (89% black). In univariate analysis, hypertension was associated with improved 1-year survival (relative risk [RR], 0.48; P = 0.002 compared with normotensive patients). This effect of hypertension was mostly caused by the associated antihypertensive treatment because untreated hypertensive patients had survival rates equal to normotensive patients (RR, 0.87; P = 0.70). On the other hand, treated hypertensive patients fared better than normotensive patients (RR, 0.41; P = 0.0006). This was also true in multivariate analysis, in which antihypertensive treatment was associated with reduced RR (RR, 0.55; P = 0.02) whereas the level of blood pressure per se was insignificant (RR, 0.99; P = 0.63 per 1 mm Hg increase in predialysis mean arterial pressure). Other factors of significance in multivariate analysis included age (RR, 1.03/y; P = 0.0004), serum albumin (RR, 0.38/g; P = 0.002), and diabetes mellitus (RR, 1.58; P = 0.06). Our study suggests that antihypertensive treatment has a favorable effect on survival in the hemodialysis population irrespective of the level of blood pressure control.

Accurate information on prevalence and status of blood pressure control among US hemodialysis patients is lacking. We have surveyed the status of blood pressure control in 649 hemodialysis patients (89.8% black) from 10 dialysis units in Mississippi. Our results show a hypertension prevalence of 72% (hypertension defined as mean arterial pressure prior to dialysis session > or = 114 mm Hg). This mean arterial pressure did not differ among black patients compared with white patients (P = 0.51). The majority of hypertensive patients (80%) had elevation of both systolic and diastolic blood pressure. Isolated systolic hypertension was present in only 20% of hypertensive patients and was not different between black and white patients (P = 0.10). Three hundred eighty-one patients (58.7% of the total population and 81.5% of the hypertensive patients) were receiving antihypertensives. Age was the only significant factor that correlated with blood pressure: older patients (> 65 years) had lower blood pressure (P < 0.0001). Race, time on dialysis, etiology of end-stage renal disease, adequacy of dialysis, and several excess volume parameters had no influence on the blood pressure level. Treated hypertensive patients had a predialysis mean blood pressure only 3 mm Hg less than the untreated hypertensive patients. No differences were found among four classes of antihypertensives with regard to the degree of blood pressure control. Patients with hypertension requiring more than one antihypertensive did not achieve a lower blood pressure than the untreated patients. There was no correlation between use of antihypertensives and the magnitude of decrease in blood pressure after dialysis.(ABSTRACT TRUNCATED AT 250 WORDS)

To evaluate whether hypothyroidism alters the adaptive responses of renal transport adenosine-triphosphatases (ATPases) to modifications in dietary K content, we examined the activities of Na-K pump and H-K pump in hypothyroid rats under basal conditions and after dietary K changes. Hypothyroidism led to a decline in Na-K pump activity in all three nephron segments examined [proximal convoluted tubule from 2,333 +/- 103 to 1,099 +/- 32, medullary thick ascending limb from 4,344 +/- 119 to 1,613 +/- 61, and cortical collecting tubule (CCT) from 1,133 +/- 45 to 640 +/- 38 pmol.mm-1 x h-1; all P < 0.01 vs. euthyroid] along with morphological changes manifest in a decrease in tubule diameter. K loading led to an increase in Na-K pump activity in the CCT of both euthyroid (from 1,133 +/- 45 to 2,269 +/- 74, pmol.mm-1 x h-1, P < 0.01) and hypothyroid (from 640 +/- 38 to 1,118 +/- 67 pmol.mm-1 x h-1, P < 0.01) animals. Furthermore, in euthyroid rats, 3 wk of K depletion led to a major increase in H-K pump activity in both the CCT (from 203 +/- 14 to 331 +/- 22 pmol.mm-1 x h-1, P < 0.01) and medullary collecting tubule (MCT, from 137 +/- 9 to 210 +/- 14 pmol.mm-1 x h-1, P < 0.01). Hypothyroidism was associated with a decline in H-K pump activity in the CCT and MCT (to 94 +/- 6 and 55 +/- 5 pmol.mm-1 x h-1, respectively; both P < 0.01 vs. euthyroid).(ABSTRACT TRUNCATED AT 250 WORDS)

Objective: To review limitations of the use of serum anion gap in clinical practice., Data Sources: Original reports and reviews., Study Selection: Sources containing the most recent pertinent information., Data Synthesis: Theoretical and practical limitations beset the use of serum anion gap. Awareness of these limitations reduces but does not eliminate wrong diagnoses based on the anion gaps., Conclusions: Serum anion gap has a limited value in the differential diagnosis of acid-base disorders and can be misleading.

The role of extrarenal potassium homeostasis is well recognized as a major mechanism for the acute defense against the development of hyperkalemia. The purpose of this report is to examine whether or not the various mechanisms of extrarenal potassium regulation are intact in patients with end-stage renal disease (ESRD). The available data suggest that with the development of ESRD and the uremic syndrome there is impaired extrarenal potassium metabolism that is related to a defect in the Na,K-adenosine triphosphatase (ATPase). The responsiveness of uremic patients to the various effector systems that regulate extrarenal potassium handling is discussed. Insulin is well positioned to play an important role in the regulation of plasma potassium concentration in patients with impaired renal function. The role of basal insulin may be even more important than previously appreciated, since somatostatin infusion causes a much greater increase in the fasting plasma potassium in rats with renal failure than in controls. Furthermore, stimulation of endogenous insulin by oral glucose results in a greater intracellular translocation of potassium in uremic rats than in controls. Under at least two common physiologic circumstances, feeding and vigorous exercise, endogenous catecholamines might also act to defend against acute increments in extracellular potassium concentration. However, it is important to appreciate that the response to beta 2-adrenoreceptor-mediated internal potassium disposal is heterogeneous as judged by the variable responses to epinephrine infusion. Based on the evidence presented in this report, a regimen for the treatment of life-threatening hyperkalemia is outlined. Interpretation of the available data demonstrate that bicarbonate should not be relied on as the sole initial treatment for severe hyperkalemia, since the magnitude of the effect of bicarbonate on potassium is variable and may be delayed. The initial treatment for life-threatening hyperkalemia should always include insulin plus glucose, as the hypokalemic response to insulin is both prompt and predictable. Combined treatment with beta 2-agonists and insulin is also effective and may help prevent insulin-induced hypoglycemia.

Experiments were performed on 14 fentanyl-pentobarbital-anesthetized dogs to assess changes in myocardial oxygen supply/demand relations during intravenous infusions of phenylephrine (2.8 micrograms.kg-1.min-1). Myocardial blood flow was measured with radioactive microspheres. Myocardial oxygen and lactate extraction were determined. Myocardial oxygen consumption was calculated with the Fick equation. In series 1, measurements were obtained during phenylephrine-induced pressor responses. In series 2, measurements were obtained with aortic pressure maintained constant with an extracorporeal reservoir during phenylephrine infusion, so that coronary vasomotor responses could be assessed in the absence of increases in ventricular afterload and perfusion pressure. In series 1, the phenylephrine-induced increase in mean aortic pressure (+42%) was accompanied by proportional (60%) increases in myocardial blood flow and myocardial oxygen consumption and with no change in the endocardium-to-epicardium flow ratio, oxygen extraction, coronary sinus oxygen tension and oxygen saturation, or myocardial lactate extraction. In series 2, phenylephrine infusion caused a transmurally uniform 15% decrease in myocardial blood flow combined with a 10% decrease in myocardial oxygen consumption. The coronary arteriovenous oxygen difference increased modestly (+5%), resulting in small decreases in coronary sinus oxygen tension and oxygen saturation, whereas lactate extraction was unaffected. The present findings suggest that phenylephrine has a direct vasoconstrictor effect in the coronary circulation that is weak and completely overridden by metabolic autoregulatory mechanisms in response to pressure-induced augmentations in cardiac workload. The authors conclude that the myocardium is not at risk when phenylephrine is used to treat hypotension in patients with adequate cardiac function and coronary vasodilator reserve.