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1.
Niger J Clin Pract ; 26(1): 55-58, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36751824

ABSTRACT

Background and Aim: Bilirubin can have a toxic effect on the brain, so newborns must be carefully checked to identify those who may develop significant hyperbilirubinemia and bilirubin encephalopathy (kernicterus). The study aimed to determine if cord blood albumin could be utilized to predict the onset of significant newborn jaundice in healthy-term babies. Patients and Methods: A cohort study was carried out in AL-Zahraa teaching hospital in AL-Najaf city during the period from January 1 to November 1, 2020. A randomized 100 full-term healthy neonates were enrolled. A blood sample was drawn by milking the cord and sent for serum albumin estimation. Patients were then followed up on the third and fifth days of life for total serum bilirubin (TSB). Results: Out of 100 healthy-term neonates that were included in this study, 60 of them had low cord blood albumin (<2.8 g/dl), and 40 of them had normal cord blood albumin (≥2.8 g/dl) with an age range of 1-5 days. There is a statistically significant difference between low cord blood albumin and significant neonatal jaundice on the third day with a 5 times more risk of developing significant jaundice than neonates with normal cord blood albumin. Conclusion: Cord blood albumin levels are sensitive to predicting subsequent neonatal jaundice in the healthy term newborn.


Subject(s)
Jaundice, Neonatal , Serum Albumin , Humans , Infant, Newborn , Bilirubin , Cohort Studies , Fetal Blood , Jaundice, Neonatal/diagnosis , Predictive Value of Tests
2.
Int J Biol Macromol ; 180: 654-666, 2021 Jun 01.
Article in English | MEDLINE | ID: mdl-33722623

ABSTRACT

The present work developed porous carboxymethyl cellulose (CMC) carbon film from lignocellulosic based materials as supercapacitor electrode. Porous CMC carbon films of bamboo (B) and oil palm empty fruit bunch (O) were prepared through simple incipient wetness impregnation method followed by calcination process before incorporation with manganese oxide (Mn2O3). The carbonization produced porous CMC carbon whereby CMCB exhibited higher surface area than CMCO. After Mn2O3 incorporation, the crystallite size of CMCB and CMCO were calculated as 50.09 nm and 42.76 nm, respectively whereas Mn2O3/CMCB and Mn2O3/CMCO composite films were revealed to be 26.71 nm and 35.60 nm in size, respectively. Comparatively, the Mn2O3/CMCB composite film exhibited higher electrochemical performance which was 31.98 mF cm-2 as compared to 24.15 mF cm-2 by Mn2O3/CMCO composite film and both CMC carbon films with fairly stable cycling stability after 1000 charge-discharge cycles. Therefore, it can be highlighted that Mn2O3/CMC composite film as prepared from bamboo and oil palm fruit can potentially become the new electrode materials for supercapacitor application.


Subject(s)
Carbon/chemistry , Carboxymethylcellulose Sodium/chemistry , Cellulose/chemistry , Lignin/chemistry , Manganese Compounds/chemistry , Oxides/chemistry , Arecaceae/chemistry , Cellulose/ultrastructure , Electric Capacitance , Electrodes , Lignin/ultrastructure , Microscopy, Electron, Scanning/methods , Microscopy, Electron, Transmission , Porosity , Sasa/chemistry
3.
Malays Fam Physician ; 15(1): 50-53, 2020.
Article in English | MEDLINE | ID: mdl-32284806

ABSTRACT

Atrial ectopic rhythm is one of the most common fetal arrhythmias that can present during the prenatal period. Detection of fetal arrhythmia can be made by auscultating fetal heart rate and rhythm using a fetal handheld Doppler, and this can be done even in a resource-limited setting. The finding of an abnormal fetal heart rate and rhythm should prompt early referral to a pediatric cardiologist, as this may improve clinical outcomes. We present a case of atrial ectopic rhythm detected in utero using a handheld Doppler.

4.
J Psychiatr Ment Health Nurs ; 25(3): 201-213, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29283492

ABSTRACT

WHAT IS KNOWN ON THE SUBJECT?: It is generally felt that it is helpful for mental health nurses to control their emotions during their work. There are different approaches, but there is growing acceptance that different emotions may need different coping strategies. There is lots of evidence that nurses sometimes feel anger in a number of situations, but the research about anger in mental health nurses has never been examined as a whole. WHAT THIS PAPER ADDS TO EXISTING KNOWLEDGE?: We have systematically identified all previous research where nurses completed measures that tried to measure their anger in certain situations, compared it to other people or investigated how it affected them or what its relationship was with their practice. Only a few studies have measured nurses' anger. However, it seems that while nurses are not generally angrier than any other group, they do often feel anger in relation to management of patient aggression and their job situation more generally. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: Anger is the most commonly reported problematic emotion for mental health nurses. It may influence their practice and affect their well-being. This has implications for staff support and training. ABSTRACT: Introduction Emotional regulation is important in mental health nursing practice, but individual emotions may require different regulation strategies. There is ample evidence that nurses experience anger specifically during their work, for example when experiencing patient aggression. It is, therefore, important to consolidate what is known about how anger manifests in mental health nursing practice. AIM: We aimed to systematically identify, evaluate and synthesize results from studies about mental health nurses and anger, where anger was measured objectively. METHODS: Systematic literature review based on PRISMA guidelines. RESULTS: We identified 12 studies. A range of validated and nonvalidated instruments was used. Mental health nurses may have lower levels of anger than normative samples, but anger is commonly reported as an issue for them. Anger was studied in relation to its links with (1) clinical management of patients, notably violence containment; and (2) employment issues more generally, notably job motivation. Anger is related to nurses' attitudes about the acceptability of coercion, but there is no evidence that it results in more coercion. IMPLICATIONS FOR PRACTICE: Nurses should be aware of the potential influence of anger on their practice. Anger, specifically, should be considered when supporting mental health nurses, for example in clinical supervision. Emotional regulation training should target anger.


Subject(s)
Anger , Attitude of Health Personnel , Nurses/psychology , Psychiatric Nursing , Humans
5.
Phys Rev Lett ; 114(12): 126804, 2015 Mar 27.
Article in English | MEDLINE | ID: mdl-25860767

ABSTRACT

We present magneto-Raman scattering studies of electronic inter-Landau level excitations in quasineutral graphene samples with different strengths of Coulomb interaction. The band velocity associated with these excitations is found to depend on the dielectric environment, on the index of Landau level involved, and to vary as a function of the magnetic field. This contradicts the single-particle picture of noninteracting massless Dirac electrons but is accounted for by theory when the effect of electron-electron interaction is taken into account. Raman active, zero-momentum inter-Landau level excitations in graphene are sensitive to electron-electron interactions due to the nonapplicability of the Kohn theorem in this system, with a clearly nonparabolic dispersion relation.

6.
Sci Rep ; 4: 5517, 2014 Jul 01.
Article in English | MEDLINE | ID: mdl-24980150

ABSTRACT

Plasmonics has established itself as a branch of physics which promises to revolutionize data processing, improve photovoltaics, and increase sensitivity of bio-detection. A widespread use of plasmonic devices is notably hindered by high losses and the absence of stable and inexpensive metal films suitable for plasmonic applications. To this end, there has been a continuous search for alternative plasmonic materials that are also compatible with complementary metal oxide semiconductor technology. Here we show that copper and silver protected by graphene are viable candidates. Copper films covered with one to a few graphene layers show excellent plasmonic characteristics. They can be used to fabricate plasmonic devices and survive for at least a year, even in wet and corroding conditions. As a proof of concept, we use the graphene-protected copper to demonstrate dielectric loaded plasmonic waveguides and test sensitivity of surface plasmon resonances. Our results are likely to initiate wide use of graphene-protected plasmonics.

7.
Nano Lett ; 14(6): 3270-6, 2014 Jun 11.
Article in English | MEDLINE | ID: mdl-24844319

ABSTRACT

Hexagonal boron nitride is the only substrate that has so far allowed graphene devices exhibiting micrometer-scale ballistic transport. Can other atomically flat crystals be used as substrates for making quality graphene heterostructures? Here we report on our search for alternative substrates. The devices fabricated by encapsulating graphene with molybdenum or tungsten disulfides and hBN are found to exhibit consistently high carrier mobilities of about 60 000 cm(2) V(-1) s(-1). In contrast, encapsulation with atomically flat layered oxides such as mica, bismuth strontium calcium copper oxide, and vanadium pentoxide results in exceptionally low quality of graphene devices with mobilities of ∼1000 cm(2) V(-1) s(-1). We attribute the difference mainly to self-cleansing that takes place at interfaces between graphene, hBN, and transition metal dichalcogenides. Surface contamination assembles into large pockets allowing the rest of the interface to become atomically clean. The cleansing process does not occur for graphene on atomically flat oxide substrates.

8.
Nature ; 497(7451): 594-7, 2013 May 30.
Article in English | MEDLINE | ID: mdl-23676678

ABSTRACT

Superlattices have attracted great interest because their use may make it possible to modify the spectra of two-dimensional electron systems and, ultimately, create materials with tailored electronic properties. In previous studies (see, for example, refs 1-8), it proved difficult to realize superlattices with short periodicities and weak disorder, and most of their observed features could be explained in terms of cyclotron orbits commensurate with the superlattice. Evidence for the formation of superlattice minibands (forming a fractal spectrum known as Hofstadter's butterfly) has been limited to the observation of new low-field oscillations and an internal structure within Landau levels. Here we report transport properties of graphene placed on a boron nitride substrate and accurately aligned along its crystallographic directions. The substrate's moiré potential acts as a superlattice and leads to profound changes in the graphene's electronic spectrum. Second-generation Dirac points appear as pronounced peaks in resistivity, accompanied by reversal of the Hall effect. The latter indicates that the effective sign of the charge carriers changes within graphene's conduction and valence bands. Strong magnetic fields lead to Zak-type cloning of the third generation of Dirac points, which are observed as numerous neutrality points in fields where a unit fraction of the flux quantum pierces the superlattice unit cell. Graphene superlattices such as this one provide a way of studying the rich physics expected in incommensurable quantum systems and illustrate the possibility of controllably modifying the electronic spectra of two-dimensional atomic crystals by varying their crystallographic alignment within van der Waals heterostuctures.

9.
Science ; 340(6138): 1311-4, 2013 Jun 14.
Article in English | MEDLINE | ID: mdl-23641062

ABSTRACT

The isolation of various two-dimensional (2D) materials, and the possibility to combine them in vertical stacks, has created a new paradigm in materials science: heterostructures based on 2D crystals. Such a concept has already proven fruitful for a number of electronic applications in the area of ultrathin and flexible devices. Here, we expand the range of such structures to photoactive ones by using semiconducting transition metal dichalcogenides (TMDCs)/graphene stacks. Van Hove singularities in the electronic density of states of TMDC guarantees enhanced light-matter interactions, leading to enhanced photon absorption and electron-hole creation (which are collected in transparent graphene electrodes). This allows development of extremely efficient flexible photovoltaic devices with photoresponsivity above 0.1 ampere per watt (corresponding to an external quantum efficiency of above 30%).

10.
Proc Natl Acad Sci U S A ; 110(9): 3282-6, 2013 Feb 26.
Article in English | MEDLINE | ID: mdl-23401538

ABSTRACT

Capacitance measurements provide a powerful means of probing the density of states. The technique has proved particularly successful in studying 2D electron systems, revealing a number of interesting many-body effects. Here, we use large-area high-quality graphene capacitors to study behavior of the density of states in this material in zero and high magnetic fields. Clear renormalization of the linear spectrum due to electron-electron interactions is observed in zero field. Quantizing fields lead to splitting of the spin- and valley-degenerate Landau levels into quartets separated by interaction-enhanced energy gaps. These many-body states exhibit negative compressibility but the compressibility returns to positive in ultrahigh B. The reentrant behavior is attributed to a competition between field-enhanced interactions and nascent fractional states.

11.
Strahlenther Onkol ; 189(3): 246-54, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23361139

ABSTRACT

BACKGROUND AND PURPOSE: Tumor hypoxia is a major problem in radiation therapy of solid tumors because of the radiosensitizing effect of oxygen. Nitroimidazole-containing compounds are oxygen mimetics accumulating in hypoxic tumor areas. However, the broad use of 2-nitroimidazoles as a hypoxic radiosensitizer is limited by their partially low efficacy and/or high neurotoxicity. MATERIALS AND METHODS: Here, we characterized the in vitro hypoxic cytotoxicity and hypoxic radiosensitizing efficacy of N,N,N-tris [2-(2-nitro-1H-imidazol-1-yl)ethyl]amine (PRC) in a hypoxia-sensitive lymphoma and a hypoxia-resistant glioblastoma cell line by colony formation assay and flow cytometry. RESULTS: PRC exerted high hypoxic cytotoxic and radiosensitizing action on both cell lines at almost absent toxicity under normoxic conditions. In particular, under hypoxia, but not normoxia, PRC targeted the mitochondria resulting in oxidative stress, G(2)/M cell cycle arrest, and triggering of the intrinsic apoptosis pathway. CONCLUSION: Our in vitro findings suggest that PRC might be a promising new 2-nitroimidazole for improving radiation therapy of hypoxic tumors in vivo.


Subject(s)
Antineoplastic Agents/pharmacology , Cell Hypoxia/drug effects , Cell Survival/drug effects , Ethylamines/pharmacology , Nitroimidazoles/pharmacology , Radiation-Sensitizing Agents/pharmacology , Apoptosis/drug effects , Cell Line, Tumor , Dose-Response Relationship, Drug , Flow Cytometry , Humans , In Vitro Techniques , Jurkat Cells , Mitochondria/drug effects , Reactive Oxygen Species , Tumor Stem Cell Assay
12.
Nat Mater ; 12(4): 304-9, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23314104

ABSTRACT

The non-trivial behaviour of phase is crucial for many important physical phenomena, such as, for example, the Aharonov-Bohm effect and the Berry phase. By manipulating the phase of light one can create 'twisted' photons, vortex knots and dislocations which has led to the emergence of the field of singular optics relying on abrupt phase changes. Here we demonstrate the feasibility of singular visible-light nano-optics which exploits the benefits of both plasmonic field enhancement and the peculiarities of the phase of light. We show that properly designed plasmonic metamaterials exhibit topologically protected zero reflection yielding to sharp phase changes nearby, which can be employed to radically improve the sensitivity of detectors based on plasmon resonances. By using reversible hydrogenation of graphene and binding of streptavidin-biotin, we demonstrate an areal mass sensitivity at a level of fg mm(-2) and detection of individual biomolecules, respectively. Our proof-of-concept results offer a route towards simple and scalable single-molecule label-free biosensing technologies.

13.
Nat Mater ; 11(9): 764-7, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22842512

ABSTRACT

By stacking various two-dimensional (2D) atomic crystals on top of each other, it is possible to create multilayer heterostructures and devices with designed electronic properties. However, various adsorbates become trapped between layers during their assembly, and this not only affects the resulting quality but also prevents the formation of a true artificial layered crystal upheld by van der Waals interaction, creating instead a laminate glued together by contamination. Transmission electron microscopy (TEM) has shown that graphene and boron nitride monolayers, the two best characterized 2D crystals, are densely covered with hydrocarbons (even after thermal annealing in high vacuum) and exhibit only small clean patches suitable for atomic resolution imaging. This observation seems detrimental for any realistic prospect of creating van der Waals materials and heterostructures with atomically sharp interfaces. Here we employ cross sectional TEM to take a side view of several graphene-boron nitride heterostructures. We find that the trapped hydrocarbons segregate into isolated pockets, leaving the interfaces atomically clean. Moreover, we observe a clear correlation between interface roughness and the electronic quality of encapsulated graphene. This work proves the concept of heterostructures assembled with atomic layer precision and provides their first TEM images.

14.
Science ; 335(6071): 947-50, 2012 Feb 24.
Article in English | MEDLINE | ID: mdl-22300848

ABSTRACT

An obstacle to the use of graphene as an alternative to silicon electronics has been the absence of an energy gap between its conduction and valence bands, which makes it difficult to achieve low power dissipation in the OFF state. We report a bipolar field-effect transistor that exploits the low density of states in graphene and its one-atomic-layer thickness. Our prototype devices are graphene heterostructures with atomically thin boron nitride or molybdenum disulfide acting as a vertical transport barrier. They exhibit room-temperature switching ratios of ≈50 and ≈10,000, respectively. Such devices have potential for high-frequency operation and large-scale integration.

15.
Orthop Traumatol Surg Res ; 98(1): 68-74, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22244250

ABSTRACT

INTRODUCTION: Valgus high tibial osteotomy is considered to be an effective treatment for unicompartmental medial osteoarthritis. It is generally admitted that tibial slope increases after open-wedge high tibial osteotomy and decreases after closing-wedge high tibial osteotomy. However, the effects on posterior tibial slope of closing- or opening-wedge osteotomies remain controversial. HYPOTHESIS: We analyzed the modifications of tibial slope after opening- and closing-wedge high tibial osteotomies and compared the results of these two procedures. We hypothesized that there was no difference in postoperative tibial slope between opening and closing-wedge osteotomies. PATIENTS AND METHODS: This prospective consecutive nonrandomized multicenter study was conducted between January 2008 and March 2009 and included 321 patients: 205 men and 116 women. A total of 224 patients underwent an opening-wedge high tibial osteotomy and 97 a closing-wedge osteotomy. The mean age was 52 years ± 9 and the mean body mass index was 28kg/m(2) ± 5. The main etiology was primary arthritis. Posterior tibial slope was measured preoperatively and at the last follow-up on a lateral radiograph in relation to the posterior tibial cortex. RESULTS: In the opening-wedge group, a definite 0.6° increase in tibial slope (P=0.016) was observed. In the closing-wedge group, a definite 0.7° decrease in tibial slope (P=0.02) was found. Fourteen percent of the opening-wedge osteotomies increased tibial slope by 5° or more versus only 2% of the closed-wedge osteotomies (P<0.001). Twelve percent of the closing-wedge high tibial osteotomies led to a decrease of 5° or more of the tibial slope versus 7% of the opening-wedge osteotomies (P<0.02). DISCUSSION AND CONCLUSION: These results confirm what is generally reported in the literature, i.e., an increase in tibial slope in opening-wedge high tibial osteotomy and a decrease in the slope in closing-wedge osteotomies. These tibial slope changes appear to be very limited in this series, less than 1° on average. However, there was a bias since the open-wedge technique was preferred in cases with substantial varus deformity. We emphasize the importance of surgical technique to avoid alteration of the tibial slope, particularly in opening-wedge high tibial osteotomy for which we recommend a release of posterior soft tissue and a complete osteotomy of the posterior cortex of the tibia. LEVEL OF EVIDENCE: III. Prospective consecutive nonrandomized multicenter study.


Subject(s)
Knee Joint/surgery , Osteoarthritis, Knee/surgery , Osteotomy/methods , Tibia/diagnostic imaging , Tibia/surgery , Female , Follow-Up Studies , Humans , Knee Joint/diagnostic imaging , Male , Middle Aged , Osteoarthritis, Knee/diagnostic imaging , Prospective Studies , Radiography , Treatment Outcome
16.
Open Orthop J ; 4: 126-31, 2010 Mar 02.
Article in English | MEDLINE | ID: mdl-20448834

ABSTRACT

The clinical outcomes of a consecutive series of deep total joint infections treated with a prosthesis retaining protocol were reviewed. The treatment of deep periprosthetic joint infections is challenging. In recent years, two-stage exchange arthroplasty has emerged as the gold standard for successful elimination of infection. With success rates averaging 82% to 96%, this treatment method has both the highest and most consistent rate of infection eradication. Another alternative in the treatment of the deep periprosthetic infection is the single-stage exchange arthroplasty. Successful eradication of infection after single-stage exchange arthroplasty has been reported to average from 60% to 83% after total hip infections. While both the single and two-stage exchange arthroplasty are viable treatment options, they are associated with negative factors such as they are time consuming, expensive, and may entail a 6- to 12-week period with a minimally functioning extremity after prosthesis removal. This paper reports the general principles of management, the treatment of acute infection occurring in the postoperative period or later, and the treatment of chronic infection by exchange arthroplasty or resection arthroplasty.

17.
Indian J Pharm Sci ; 71(3): 252-8, 2009 May.
Article in English | MEDLINE | ID: mdl-20490290

ABSTRACT

The aim of the present study was the determination of formulation factors and the in vitro evaluation of an extended release dosage form of a freely soluble weakly basic drug (alfuzosin hydrochloride). Binary mixer of one hydrophilic polymer (hydroxypropylmethylcellulose) and one directly compressible Eudragit (RS PO) was used in tablets prepared by direct compression. The amounts of both polymers were taken as independent variables for the 3(2) Factorial design. The percent drug releases at 1, 6, 12 and 20 h were selected as responses. The main effect and interaction terms were quantitatively evaluated using mathematical model. Dissolution data were fitted to zero order, first order, and Higuchi's release kinetics to evaluate kinetic data. Both the diffusion and erosion mechanisms were responsible for drug release as shown by the power law. The release of Alfuzosin was prolonged for 20 h by binary mixer indicating the usefulness of the formulations for once daily dosage forms.

19.
Rev. méd. Chile ; 131(9): 1037-1041, sept. 2003.
Article in Spanish | LILACS | ID: lil-356008

ABSTRACT

A 33 years old woman was admitted to the hospital after four days with cough, dyspnea, orthopnea and hemoptysis. Blood pressure was 170/90 mmHg, pulse was 112 and temperature was normal. She had cyanosis and a left ventricular gallop, without heart murmurs. A chest radiograph revealed pulmonary edema and echocardiogram showed a global left ventricular systolic disfunction. Oxygen and furosemide were started, but cardiopulmonary collapse ensued. The patient was supported with mechanical ventilation and treated with inotropic drugs. A right sided cardiac catheterization showed pulmonary wedge pressure of 18 mmHg and a cardiac index of 3 l/min/m2. The levels of creatinine and urea nitrogen were elevated and a urine protein was 97 mg/dl. Coagulation tests were normal except by a positive lupic anticoagulant. Markers of connective tissue diseases or vasculitis were negatives. The clinical evolution suggested that a catastrophic antiphospholipid syndrome was ongoing. Intravenous corticoids, gammaglobulin and cyclophosphamide were administered with transient improvement. On her fourth day of treatment, the patient presented sudden pulmonary bleeding and embolism. A plasmapheresis was performed with improvement of renal, cardiac and pulmonary function. After this episode, the patient has been treated with prednisone and oral anticoagulants treatment for the last two years, without further clinical events.


Subject(s)
Humans , Female , Adult , Cardiac Output, High/etiology , Antiphospholipid Syndrome/complications , Acute Disease , Catastrophic Illness , Cardiac Output, High/drug therapy , Lupus Coagulation Inhibitor/blood , Antiphospholipid Syndrome/drug therapy
20.
Nephrol Dial Transplant ; 16(5): 1009-16, 2001 May.
Article in English | MEDLINE | ID: mdl-11328908

ABSTRACT

BACKGROUND: Calcitriol is used to treat secondary hyperparathyroidism in dialysis patients. For similarly elevated parathyroid hormone (PTH) levels, the PTH response to calcitriol treatment is believed to be better in hypocalcaemic dialysis patients than in dialysis patients with higher serum calcium values. Furthermore, few studies have evaluated the rapidity of the rebound in serum PTH values after prolonged treatment with calcitriol. Our goal was to evaluate (i) the PTH response to calcitriol treatment in hypocalcaemic haemodialysis patients, (ii) the rapidity of rebound in PTH after calcitriol treatment was stopped, and (iii) whether the effect of calcitriol treatment on PTH levels could be separated from those produced by changes in serum calcium and phosphate values. METHODS: Eight haemodialysis patients (29+/-3 years) with hypocalcaemia and hyperparathyroidism were treated thrice weekly with 2 microg of intravenous calcitriol and were dialysed with a 3.5 mEq/l calcium dialysate. Parathyroid function (PTH-calcium curve) was determined before and after 30 weeks of calcitriol treatment and 15 weeks after calcitriol treatment was stopped. RESULTS: Pretreatment PTH and ionized calcium values were 907+/-127 pg/ml and 3.89+/-0.12 mg/dl (normal, 4.52+/-0.07 mg/dl). During calcitriol treatment, one patient did not respond, but basal (predialysis) PTH values in the other seven patients decreased from 846+/-129 to 72+/-12 pg/ml, P<0.001 and in all seven patients, the decrease exceeded 85%. During the 15 weeks after calcitriol treatment was stopped, a slow rebound in basal PTH values in the seven patients was observed, 72+/-12 to 375+/-44 pg/ml. Covariance analysis was used to evaluate the three tests of parathyroid function (0, 30, and 45 weeks), and showed that calcitriol treatment was associated with reductions in maximal PTH values while reductions in basal PTH were affected by ionized calcium and serum phosphate. The basal/maximal PTH ratio and the set point of calcium were associated with changes in ionized calcium. CONCLUSIONS: In haemodialysis patients with hypocalcaemia, (i) moderate to severe hyperparathyroidism responded well to treatment with calcitriol, (ii) reductions in maximal PTH were calcitriol dependent while reductions in basal PTH were affected by the ionized calcium and serum phosphate concentrations, (iii) changes in the basal/maximal PTH ratio and the set point of calcium were calcium dependent, and (iv) the delayed rebound in basal PTH levels after withdrawal of calcitriol treatment may have been due to the long duration of treatment and the marked PTH suppression during treatment.


Subject(s)
Calcitriol/administration & dosage , Calcium Channel Agonists/administration & dosage , Hyperparathyroidism/drug therapy , Hyperparathyroidism/etiology , Hypocalcemia/etiology , Renal Dialysis/adverse effects , Adult , Calcitriol/therapeutic use , Calcium/blood , Calcium Channel Agonists/therapeutic use , Female , Humans , Hyperparathyroidism/blood , Hypocalcemia/blood , Male , Parathyroid Hormone/blood
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