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Special Situations (special + situation)
Selected AbstractsTHE PHENOTYPIC VARIANCE WITHIN PLASTIC TRAITS UNDER MIGRATION-MUTATION-SELECTION BALANCEEVOLUTION, Issue 6 2006Xu-Sheng Zhang Abstract How phenotypic variances of quantitative traits are influenced by the heterogeneity in environment is an important problem in evolutionary biology. In this study, both genetic and environmental variances in a plastic trait under migration-mutation-stabilizing selection are investigated. For this, a linear reaction norm is used to approximate the mapping from genotype to phenotype, and a population of clonal inheritance is assumed to live in a habitat consisting of many patches in which environmental conditions vary among patches and generations. The life cycle is assumed to be selection-reproduction-mutation-migration. Analysis shows that phenotypic plasticity is adaptive if correlations between the optimal phenotype and environment have become established in both space and/or time, and it is thus possible to maintain environmental variance (VE) in the plastic trait. Under the special situation of no mutation but maximum migration such that separate patches form an effective single-site habitat, the genotype that maximizes the geometric mean fitness will come to fixation and thus genetic variance (VG) cannot be maintained. With mutation and/or restricted migration, VG can be maintained and it increases with mutation rate but decreases with migration rate; whereas VE is little affected by them. Temporal variation in environmental quality increases VG while its spatial variance decreases VG. Variation in environmental conditions may decrease the environmental variance in the plastic trait. [source] Collection of peripheral progenitor cells in paediatric patients with a new programme for the collection of mononuclear cellsJOURNAL OF CLINICAL APHERESIS, Issue 3 2003R. Moog Abstract When harvesting peripheral progenitor cells (PPC) in children, the special situation of their circulatory system has to be taken into account. Therefore, extracorporeal blood volume and product volume should be small to avoid side effects. Nine children (age 2,14 years, weight 12.8,58.5 kg) with malignancies underwent 10 PPC collections with the MNC programme of the Amicus blood cell separator. The disposable kit was primed with red blood cells (RBCs) or human albumin to avoid circulatory side effects. The children were monitored for blood pressure and heart rate during the whole apheresis procedure. A median blood volume of 4,577 ml (range 3,536,8,596 ml) was processed in a separation time of 270 min (range 176,331 min). The median product weight was 81 g (range 53,107 g) and the yield of CD 34 antigen expressing cells was 12.5 × 106/kg body weight (range 1.8,26 × 106/kg body weight). Only one child had to undergo a second apheresis to collect the desired transplantation dose. The median platelet contamination of the product was 0.32 × 1011 (0.13,0.85 × 1011). No circulatory side effects were observed. Blood flow alarms occurred in seven of ten aphereses and one collection had to be terminated due to insufficient flow. PPC can be efficiently collected in children with the MNC programme without circulatory side effects. The platelet contamination of the product was low due to the elutriation principle of the collection process, thereby avoiding thrombocytopenic bleeding episodes in the patients. J. Clin. Apheresis, 18:111,114, 2003. © 2003 Wiley-Liss, Inc. [source] The Art of Repair in Surgical Hair Restoration,Part II: The Tactics of RepairDERMATOLOGIC SURGERY, Issue 10 2002Robert M. Bernstein MD background. As patient awareness of new hair transplantation techniques grows, the repair of improperly planned or poorly executed procedures becomes an increasingly important part of surgical hair restoration. objective. Part II of this series is written to serve as a practical guide for surgeons who perform repairs in their daily practices. It focuses on specific repair techniques. methods. The repairs are performed by excision with reimplantation and/or by camouflage. Follicular unit transplantation is used for the restorative aspects of the procedure. results. Using punch or linear excision techniques allows the surgeon to relocate poorly planted grafts to areas that are more appropriate. The key elements of camouflage include creating a deep zone of follicular units, angling grafts in their natural direction, and using forward and side weighting of grafts to increase the appearance of fullness. In special situations, removal of grafts without reimplantation can be accomplished using lasers or electrolysis. conclusion. Meticulous surgical techniques and optimal utilization of a limited hair supply will enable the surgeon to achieve the best possible cosmetic results for patients requiring repairs. [source] The Art of Repair in Surgical Hair Restoration Part I: Basic Repair StrategiesDERMATOLOGIC SURGERY, Issue 9 2002Robert M. Bernstein MD background. An increasingly important part of many hair restoration practices is the correction of hair transplants that were performed using older, outdated methods, or the correction of hair transplants that have left disfiguring results. The skill and judgment involved in these repair procedures often exceed those needed to operate on patients who have had no prior surgery. The use of small grafts alone does not protect the patient from poor work. Errors in surgical and aesthetic judgment, performing procedures on noncandidate patients, and the failure to communicate successfully with patients about realistic expectations remain major problems. objective. This two-part series presents new insights into repair strategies and expands upon several techniques previously described in the hair restoration literature. The focus is on creative aesthetic solutions to solve the supply/demand limitations inherent in most repairs. This article is written to serve as a guide for surgeons who perform repairs in their daily practices. methods. The repairs are performed by excision with reimplantation and/or by camouflage. Follicular unit transplantation is used for the restorative aspects of the procedure. results. Using punch or linear excision techniques allows the surgeon to relocate poorly planted grafts to areas that are more appropriate. In special situations, removal of grafts without reimplantation can be accomplished using lasers or electrolysis. The key elements of camouflage include creating a deep zone of follicular units, angling grafts in their natural direction, and using forward and side weighting of grafts to increase the appearance of fullness. The available donor supply is limited by hair density, scalp laxity, and scar placement. conclusion. Presented with significant cosmetic problems and severely limited donor reserves, the surgeon performing restorative hair transplantation work faces distinct challenges. Meticulous surgical techniques and optimal utilization of a limited hair supply will enable the surgeon to achieve the best possible cosmetic results for patients requiring repairs. [source] Update on the Management of Hypertension: Recent Clinical Trials and the JNC 7JOURNAL OF CLINICAL HYPERTENSION, Issue 2004Marvin Moser MD Editor in Chief The following issues are highlighted: Emphasis is placed on the importance of systolic blood pressure elevations in estimating risk and in determining prognosis. A review of placebo-controlled clinical trials indicates that cardiovascular events are statistically significantly reduced with diuretic- or , blocker-based treatment regimens. The question of whether blood pressure lowering alone or specific medications make the difference in outcome is discussed. Based on the results of numerous trials, it is apparent that blood pressure lowering itself is probably of greater importance in reducing cardiovascular events than the specific medication used. Meta-analyses suggest, however, that the use of an agent that blocks the renin-angiotensin aldosterone system is probably more effective in diabetics and in patients with nephropathy than a regimen based on calcium channel blocker therapy. The Antihypertensive and Lipid-Lowering treatment to Prevent Heart Attack Trial (ALLHAT) reported no overall difference in coronary heart disease outcome among patients treated with a diuretic-based compared to a calcium channel blocker- or an angiotensin-converting enzyme inhibitor-based treatment program. However, patients in the diuretic group experienced fewer episodes of heart failure than in the calcium channel blocker group and fewer episodes of heart failure and strokes than those in the angiotensin-converting enzyme inhibitor group. Results were similar in diabetics and nondiabetics. Possible reasons for this outcome are discussed. The Australian National Blood Pressure 2 study, which was unblinded, reported a marginally significantly better outcome only in male patients receiving an angiotensin-converting enzyme inhibitor-based regimen compared to those receiving a diuretic-based program. Finally, the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7) is reviewed. Highlights of this report include the new designation of prehypertension, i.e., blood pressures of 120,139 mm Hg/80,89 mm Hg. The JNC 7 suggested that diuretics should be the first-step drug of choice in most patients, but listed numerous specific reasons why other agents should be used in special situations. The report stressed that the majority of patients will require two or more medications to achieve goal blood pressure. [source] Primary care needs of patients who have undergone gender reassignmentJOURNAL OF THE AMERICAN ACADEMY OF NURSE PRACTITIONERS, Issue 4 2005Mary Sobralske PhD Purpose The purpose of this article is to inform nurse practitioners (NPs) about the primary care needs of patients who have undergone gender reassignment, either by hormone therapy alone or in conjunction with surgery. Data sources Data sources used were mainly from a review of the literature about gender identity disorder and gender reassignment. Information was also gathered from several leading surgeons on gender reassignment surgical procedures and subsequent clinical considerations. Conclusions There is very little written on the primary care clinical ramifications of transsexual patients and how clinicians can adapt their approaches to healthcare delivery to accommodate their special situations. Implications for practice Implications for practice include how an NP can adapt clinical practice approaches to provide for patients who have undergone gender reassignment. Changes that occur in the transsexual process may warrant noncustomary primary healthcare screening and examination. [source] Autoindexing the diffraction patterns from crystals with a pseudotranslationACTA CRYSTALLOGRAPHICA SECTION D, Issue 6 2009Nicholas K. Sauter Rotation photographs can be readily indexed if enough candidate Bragg spots are identified to properly sample the reciprocal lattice. However, while automatic indexing algorithms are widely used for macromolecular data processing, they can produce incorrect results in special situations where a subset of Bragg spots is systematically overlooked. This is a potential outcome in cases where a noncrystallographic translational symmetry operator closely mimics an exact crystallographic translation. In these cases, a visual inspection of the diffraction image will reveal alternating strong and weak reflections. However, reliable detection of the weak-intensity reflections by software requires a systematic search for a diffraction signal targeted at specific reciprocal-space locations calculated a priori by considering all possible pseudotranslations. Care must be exercised to distinguish between true lattice diffraction and spurious signals contributed by neighboring overlapping Bragg spots, non-Bragg diffraction and noise. Such procedures have been implemented within the autoindexing program LABELIT and applied to known cases from publicly available data sets. Routine use of this type of signal search adds only a few seconds to the typical run time for autoindexing. The program can be downloaded from http://cci.lbl.gov/labelit. [source] The impact of sildenafil citrate on sexual satisfaction profiles in men with a penile prosthesis in situBJU INTERNATIONAL, Issue 1 2004J.P. Mulhall This section includes three papers, two of which describe the use of drug treatment for erectile dysfunction in special situations. The authors from New York and Chicago write about sildenafil in patients with a penile prosthesis in situ. Authors from Zurich have used apomorphine in patients with spinal cord injury and erectile dysfunction. It is often helpful to readers with an interest in the area of erectile problems to explore the use of commonly prescribed drugs in somewhat less common situations. OBJECTIVE To assess the efficacy of sildenafil in increasing penile glans tumescence and improving patient satisfaction in men with a penile prosthesis, as this remains a major treatment for erectile dysfunction but a common complaint is the lack of glans engorgement. PATIENTS AND METHODS To determine whether sildenafil combined with a penile prosthesis improves satisfaction, patients used an implant alone for at least 1 month, after which they completed the International Index of Erectile Function (IIEF) questionnaire. The same patients were then given sildenafil citrate and completed the IIEF questionnaire after using the sildenafil/implant combination. RESULTS Patients who responded to sildenafil with glans engorgement reported significantly greater satisfaction scores than with an implant alone. CONCLUSION We currently offer sildenafil citrate after implantation to all men who have a penile prosthesis placed. [source] C1 inhibitor deficiency: consensus documentCLINICAL & EXPERIMENTAL IMMUNOLOGY, Issue 3 2005M. M. Gompels Summary We present a consensus document on the diagnosis and management of C1 inhibitor deficiency, a syndrome characterized clinically by recurrent episodes of angio-oedema. In hereditary angio-oedema, a rare autosomal dominant condition, C1 inhibitor function is reduced due to impaired transcription or production of non-functional protein. The diagnosis is confirmed by the presence of a low serum C4 and absent or greatly reduced C1 inhibitor level or function. The condition can cause fatal laryngeal oedema and features indistinguishable from gastrointestinal tract obstruction. Attacks can be precipitated by trauma, infection and other stimulants. Treatment is graded according to response and the clinical site of swelling. Acute treatment for severe attack is by infusion of C1 inhibitor concentrate and for minor attack attenuated androgens and/or tranexamic acid. Prophylactic treatment is by attenuated androgens and/or tranexamic acid. There are a number of new products in trial, including genetically engineered C1 esterase inhibitor, kallikrein inhibitor and bradykinin B2 receptor antagonist. Individual sections provide special advice with respect to diagnosis, management (prophylaxis and emergency care), special situations (childhood, pregnancy, contraception, travel and dental care) and service specification. [source] | ||||||||||