The history of the development of the regular straight stem in hip arthroplasty.

Since the middle of the 20th century, total hip arthroplasty has become a very successful treatment for all end-stage diseases of the hip joint. Charnley solved with his low frictional torque arthroplasty the problem of wear and friction with the introduction of a new bearing couple and the reduction of the head size, which set the prerequisite for the further development of stem design. This narrative review presents the major developments of regular straight stems in hip arthroplasty. It does not only provide an overview of the history but also assembles the generally scarce documentation available regarding the rationale of developments and illustrates often-unsuspected links. Charnley's success is based on successfully solving the issue of fixation of the prosthetic components to the bone, using bone cement made of polymethyl-methacrylate. In the field of cemented anchorage of the stem, two principles showing good long-term revision rates emerged over the years: the force-closed and the shape-closed principles. The non-cemented anchorage bases on prosthesis models ensure enough primary stability for osteointegration of the implant to occur. For bone to grow onto the surface, not only sufficient primary stability is required but also a suitable surface structure together with a biocompatible prosthetic material is also necessary

Prevalence and treatment implications of ICD-11 complex PTSD in Australian treatment-seeking current and ex-serving military members

Background: Despite growing support for the distinction between posttraumatic stress disorder (PTSD) and complex PTSD (CPTSD) as separate diagnoses within the ICD-11 psychiatric taxonomy, the prevalence and treatment implications of CPTSD among current and ex-serving military members have not been established. Objective: The study aims were to a) establish the prevalence of provisional ICD-11 CPTSD diagnosis relative to PTSD in an Australian sample of treatment-seeking current and ex-serving military members, and b) examine the implications of CPTSD diagnosis for intake profile and treatment response. Methods: The study analysed data collected routinely from Australian-accredited treatment programmes for military-related PTSD. Participants were 480 current and ex-serving military members in this programmes who received a provisional ICD-11 diagnosis of PTSD or CPTSD at intake using proxy measures. Measures of PTSD symptoms, disturbances in self-organisation, psychological distress, mental health and social relationships were considered at treatment intake, discharge, and 3-month follow-up. Results: Among participants with a provisional ICD-11 diagnosis, 78.2% were classified as having CPTSD, while 21.8% were classified as having PTSD. When compared to ICD-11 PTSD, participants with CPTSD reported greater symptom severity and psychological distress at intake, and lower scores on relationship and mental health dimensions of the quality of life measure. These relative differences persisted at each post-treatment assessment. Decreases in PTSD symptoms between intake and discharge were similar across PTSD (dRM = −0.81) and CPTSD (dRM = −0.76) groups, and there were no significant post-treatment differences between groups when controlling for initial scores. Conclusions: CPTSD is common among treatment-seeking current and ex-serving military members, and is associated with initially higher levels of psychiatric severity, which persist over time. Participants with CPTSD were equally responsive to PTSD treatment; however, the tendency for those with CPTSD to remain highly symptomatic post-treatment suggests additional treatment components should be considered

Mouse Ribosomal RNA Genes Contain Multiple Differentially Regulated Variants

Previous cytogenetic studies suggest that various rDNA chromosomal loci are not equally active in different cell types. Consistent with this variability, rDNA polymorphism is well documented in human and mouse. However, attempts to identify molecularly rDNA variant types, which are regulated individually (i.e., independent of other rDNA variants) and tissue-specifically, have not been successful. We report here the molecular cloning and characterization of seven mouse rDNA variants (v-rDNA). The identification of these v-rDNAs was based on restriction fragment length polymorphisms (RFLPs), which are conserved among individuals and mouse strains. The total copy number of the identified variants is less than 100 and the copy number of each individual variant ranges from 4 to 15. Sequence analysis of the cloned v-rDNA identified variant-specific single nucleotide polymorphisms (SNPs) in the transcribed region. These SNPs were used to develop a set of variant-specific PCR assays, which permitted analysis of the v-rDNAs' expression profiles in various tissues. These profiles show that three v-rDNAs are expressed in all tissues (constitutively active), two are expressed in some tissues (selectively active), and two are not expressed (silent). These expression profiles were observed in six individuals from three mouse strains, suggesting the pattern is not randomly determined. Thus, the mouse rDNA array likely consists of genetically distinct variants, and some are regulated tissue-specifically. Our results provide the first molecular evidence for cell-type-specific regulation of a subset of rDNA

Ribosomal DNA Deletions Modulate Genome-Wide Gene Expression: “rDNA–Sensitive” Genes and Natural Variation

The ribosomal rDNA gene array is an epigenetically-regulated repeated gene locus. While rDNA copy number varies widely between and within species, the functional consequences of subtle copy number polymorphisms have been largely unknown. Deletions in the Drosophila Y-linked rDNA modifies heterochromatin-induced position effect variegation (PEV), but it has been unknown if the euchromatic component of the genome is affected by rDNA copy number. Polymorphisms of naturally occurring Y chromosomes affect both euchromatin and heterochromatin, although the elements responsible for these effects are unknown. Here we show that copy number of the Y-linked rDNA array is a source of genome-wide variation in gene expression. Induced deletions in the rDNA affect the expression of hundreds to thousands of euchromatic genes throughout the genome of males and females. Although the affected genes are not physically clustered, we observed functional enrichments for genes whose protein products are located in the mitochondria and are involved in electron transport. The affected genes significantly overlap with genes affected by natural polymorphisms on Y chromosomes, suggesting that polymorphic rDNA copy number is an important determinant of gene expression diversity in natural populations. Altogether, our results indicate that subtle changes to rDNA copy number between individuals may contribute to biologically relevant phenotypic variation

Localization of chromosomal DNA sequences homologous to ribosomal gene type I insertion DNA in Drosophila melanogaster

Chromosomal sites which have DNA homology to the 1 kb (kilobase pair) Bam HI restrictable fragment of the 5 kb type I insertion present in many ribosomal genes in Drosophila melanogaster , were identified by using in situ hybridization and autoradiography. XX and XY complements of polytene chromosomes showed the nucleolus and chromocenter to be heavily labeled. Of the light label over euchromatic regions, the 102C band of chromosome 4 labeled particularly intensely. In mitotic XX and XY complements, the NORs (nucleolus organizer regions) of both sex chromosomes labeled as did the centromeric heterochromatin of autosomes. Label also appeared less frequently over telomeric and euchromatic regions.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47555/1/438_2004_Article_BF00328069.pd

Methodology of calculation of construction and hydrodynamic parameters of a foam layer apparatus for mass-transfer processes

Промислова реалізація методу стабілізації газорідинного шару дозволяє значно розширити галузь застосування пінних апаратів і відкриває нові можливості інтенсифікації технологічних процесів з одночасним створенням маловідходних технологій. У статті встановлені основні параметри, що впливають на гідродинаміку пінних апаратів, розглянуті основні конструкції та режими роботи пінних апаратів. Виявлено зв'язок гідродинамічних параметрів. Розглянуто гідродинамічні закономірності пінного шару. Вказані фактори, що впливають на процес масообміну, як в газовій, так і в рідкій фазах. Проведений аналіз ряду досліджень показав, що перспективним напрямком інтенсифікації процесу масообміну є розробка апаратів з трифазним псевдозрідженим шаром зрошуваної насадки складних форм із сітчастих матеріалів. Отже, необхідне проведення спеціальних досліджень гідродинамічних режимів роботи апарату з сітчастою насадкою і визначенням параметрів, що впливають на швидкість переходу насадки з одного режиму в інший.Industrial implementation of the stabilization method of the gas-liquid layer can significantly expand the field of use of foaming apparatus and opens up new opportunities for intensifying technological processes with the simultaneous creation of low-waste technologies. The article establishes the basic parameters influencing the hydrodynamics of foam apparatus, considers the basic constructions and operating modes of foam apparatus. The connection of hydrodynamic parameters is revealed. The hydrodynamic laws of the foam layer are considered. The indicated factors affecting the process of mass transfer, both in the gas and in the liquid phases. The conducted analysis of a number of studies showed that the perspective direction of intensification of the mass transfer process is the development of apparatuses with a three-phase fluidized bed of an irrigated nozzle of complex forms with mesh materials

Three Paramagnetic Reduction Stages of Phenyl Substituted 1,2:9,10 Dibenzo[2.2]paracyclophane-1,9-dienes. Radical Anions, Triplet Dianions and Radical Trianions as studied by ESR and ENDOR Spektroscopy

Reduction of di- and tetraphenyl-substituted 1,2:9,10-dibenzo[2.2]paracyclophane-1,9-dienes, 3, 3-d'₂, 4,5, and 5-tBu₄ with potassium in ethereal solvents has been monitored by ESR and ENDOR spectroscopy. In each case, the first reduction step yields a radical anion in which the unpaired electron resides in one of the two lateral biphenyl or o-terphenyl mystems orthogonal to the central phane unit. Except under conditions of strong association with the K⁺ counterion, electron exchange between the two π-ystems is fast on the hyperfine time scale. Upon further reduction, a second electron is taken up, as revealed by the appearance of triplet dianions bearing one unpaired electron in each of the two lateral π-ystems (separation ca. 1 nm). The singlet state of the dianion of 5 has been estimated to lie only slightly higher (ca. 2 kJ mol⁻¹) than the triplet state; the simultaneous presence of the singlet dianions of 3 and 5 in the solutions is compatible with evidence from NMR spectroscopy. An even more prolonged contact with potassium metal leads to radical trianions with the unpaired electron accommodated in the central phane unit. These radical trianions can thus be regarded as the radical anions of [2.2]paracyclophane having two negatively charged lateral π-ystems attached to it. Detection of trianions in a quartet state by ESR spectroscopy proved to be difficult under the experimental conditions used. The sequential uptake of three electrons by 3-5 is discussed in the light of the reduction potentials of the constituent π-ystems