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Symptom Burden After Dialysis Initiation and Its Association With Hospitalization.

RATIONALE & OBJECTIVE: Symptom burden is distressing for patients living with kidney failure, but there is limited information about the combination of symptoms and individual symptoms that most strongly predict health care use in this group. We classified and summarized patients' symptom burden levels and changes over time and estimated associations with hospitalizations among patients receiving incident hemodialysis. STUDY DESIGN: Longitudinal, observational. SETTING & PARTICIPANTS: Individuals initiating dialysis in the United States. EXPOSURE: Kidney Disease Quality of Life-36 (KDQOL-36) measure. OUTCOME: First hospitalization after dialysis initiation. ANALYTICAL APPROACH: Latent transition analysis was used to identify symptom burden classes using the KDQOL-36. Cox regression models were used to assess whether individual KDQOL-36 symptoms and symptom burden groups were associated with hospitalization risk after dialysis initiation, independent of demographics and comorbid conditions. RESULTS: 1,818 participants were Black (29%), were aged >65 years (59%), were women (42%), had diabetes (49%), and had hypertension (74%). Latent transition analysis identified the following 3 symptom burden groups: (1) low (low severity of all symptoms and kidney disease impacts), (2) moderate (high physical health impact and overall burden of kidney disease), and (3) high (high levels of all symptoms and kidney disease impact). After adjusting for patient characteristics, all KDQOL-36 scales except the Effects of Kidney Disease scale were associated with a higher hazard of hospitalization. Using the symptom burden groups, a high symptom burden was associated with a 20% increase in the hazard of hospitalization. A 1-category worsening in pain interference and in fatigue was associated with a 12% and an 8% increased hazard of hospitalization, respectively. LIMITATIONS: Findings may not generalize outside the United States. CONCLUSIONS: Pain interference and fatigue, as well as an overall symptom burden, are useful prognostic indicators in patients receiving in-center hemodialysis. Symptom burden should remain a treatment target in hemodialysis.

Hemodialysis

Online Social Anxiety in the Digital Age: Transitions, Predictors, and Mental Health Associations in Emerging Adulthood.

BACKGROUND: Online social anxiety (OSA), a multidimensional form of social evaluative anxiety in online social contexts, disproportionately affects emerging adults who constitute the largest active group of media users and face heightened psychological sensitivity due to growing pressures and immature sociocognitive regulation during the transition to adulthood. However, its heterogeneity, transitions, and longitudinal associations with mental health outcomes remain underexplored. METHODS: This study utilized data from two waves of a three-wave longitudinal survey, with 849 Chinese participants (Meanage = 21.6 years; 50.4 percent female) assessed at 4-month intervals. Individuals were classified using latent profile analysis and the stability and changes of profiles were assessed via latent transition analysis (LTA). Multinomial logistic regressions were conducted separately at baseline and follow-up to identify correlates of profile membership. Predictors of profile transitions were examined using manual three-step LTA models, and associations between latent transition patterns and follow-up mental health outcomes were examined using BCH-LTA distal outcome analyses controlling for the corresponding baseline symptom level. RESULTS: Four profiles of OSA were identified: low, privacy-sensitive, moderate-high, and high OSA. Extreme profiles (low/high OSA) showed high stability (80.4 percent and 79.1 percent), while privacy-sensitive OSA exhibited the lowest stability (55.1 percent). Profile memberships were influenced by social-cognitive biases and digital interaction, particularly fear of negative evaluation and online interpersonal trust, whereas profile transitions were mainly associated with anxiety. Transitions toward less severe OSA profiles were generally associated with better subsequent mental health, whereas transitions toward more severe profiles corresponded to poorer outcomes, particularly for offline social anxiety. CONCLUSION: OSA was heterogeneous in its manifestation, severity and transitions. Personalized and early interventions targeting profile-specific vulnerabilities are critical to prevent the worsening of OSA and mitigate its psychological burden.

Humans

Understanding psychosocial adjustment in military-to-civilian transition: A latent profile analysis of ex-serving Australian Defence Force members.

Military-to-civilian transition is a critical life stage that can expose veterans to elevated risks of psychological distress, social difficulties, and reduced wellbeing. Although psychosocial factors are central to successful reintegration, little is known about distinct patterns of needs among ex-serving Australian Defence Force (ADF) members. This study used latent profile analysis (LPA) to identify psychosocial needs profiles across five domains of the Military-Civilian Adjustment and Reintegration Measure (M-CARM) in a sample of 725 ex-serving ADF members. The optimal three-class solution identified: a Low Adjustment Need (LAN) group (20.7%) reporting minimal reintegration challenges; a Cultural Adjustment Need (CAN) group (42.9%) characterized by cultural adaptation difficulties, particularly beliefs about civilians and regimentation; and a Cultural and Psychological Need (CPN) group (36.4%) showing broader challenges across beliefs about civilians, purpose and connection, regimentation, and resentment and regret. The CAN group was more likely to be male, have lower educational attainment, and have no combat deployment history. The CPN group was similarly male dominated with lower education, and was additionally characterized by Navy service, unemployment or not being in the labor force, and medical discharge. Compared with the LAN group, both CAN and CPN groups reported higher levels of depression, anxiety, posttraumatic stress, and nightmare distress, as well as poorer quality of life and greater functional impairment. These findings highlight persistent reintegration challenges among veterans and support the need for stratified support models, ranging from psychoeducation to intensive multidisciplinary care, to better address diverse psychosocial needs of ex-serving ADF members.

Australian defense force

[Minimal cardiac transit times in the diagnosis of heart disease: measurements with the gamma retina V and indium-113m. The influence on central volume relationships of long-term digitalis therapy in patients with latent and manifest coronary insufficiency].

Using Indium-113m and the Gamma Retina V (Fucks-Knipping Camera), the minimal cardiac transit times (MTTs) were measured radiocardiographically from the right auricle to the aortic root. This analysis served to determine the relation between stroke volume and the segment volume of the part of circulation between the right auricle and the aortic root. In 39 patients with myocardial insufficiency of different clinical degree the effectiveness of digitalization was, up to a period of 5 years, measured by means of the volume relation mentioned above. The following conclusions can be drawn from the results: digitalization of patients with myocardial insufficiency leads to an improvement of the impaired relation of central volumes. In patients with diminished cardiac reserve the improvement is drastic and often results in a nearly complete normalization. The data remain constant during therapy even for an observation period of 5 years. Digitalization of patients with congestive heart failure only leads to a partial improvement. In contrast to patients with diminished cardiac reserve this effect is temporary. The different behaviour of the relation between stroke volume and segment volume in patients with diminished cardiac reserve and congestive heart failure under prolonged administration of digitalis points to the necessity of treatment with digitalis in the early stage of myocardial disease.

Adult

[Circular dichroism of DNA complexes with dyes. III. Effect of latent optical activity and the structure of the complexes].

Circular dichroism anisotropy was studied both theoretically and experimentally for the complexes of DNA and dsRNA with dyes (proflavine, 2,7-di-t-butyl proflavine, "Hoechst-33258") and antibiotics (distamycin A, netropsin and olivomycin). Theoretical analysis showed that general features of CD anisotropy, revealed in the previous studies (CD components--delta epsilon parallel to and delta epsilon perpendicular--are ten times or more bigger than the CD-effect without orientation, and delta epsilon parallel to approximately 2 delta epsilon perpendicular) are due to the existence of a specific effect named "latent" optical activity (LOA). This effect can be observed in many cases of non-chiral symmetrical chromophores if they are oriented. The effect is due to the excitation of an electrical dipole transition and a perpendicular magnetic dipole transition (or quadrupole transition) of a molecule. The amplitude and the sign of the LOA-effect depends on the orientation of the chromophores with respect to the light beam; with a random orientation the mutual compensation of LOA-effects of different chromophores happens and no LOA-effect appears. The analitycal expressions relating the value of LOA-effect of the system with electronical characteristics of the chromophores and the geometrical parametra of their arrangement was obtained. The experimental data obtained for the oriented complexes of DNA and dsRNA with proflavine made it possible to determine an angle between the chromophore and the plane perpendicular to the DNA axis--gamma. For the calf thymus DNA gamma = = + 1.8 +/- 0.4 degrees, for the phage T2 DNA gamma = + 2.2 +/- 0.4 degrees, and for phage f2 dsRNA gamma=--3.5 +/- +/- 0.5 degrees. These results, obtained at relatively low concentrations of the bound proflavine (r approximately 0.01), are in accordance with the intercalating mode of the dye binding. A study of CD anisotropy of DNA complexes with other ligands showed that many different chromophores possess LOA-effect. This phenomenon can be used to obtain both spectroscopic and structural information about the systems similar to those reported here.

Acridines

Transcriptional activation of regenerative hematopoiesis via microenvironmental sensing.

Transition between activation and quiescence states in hematopoietic stem and progenitor cells (HSPCs) is tightly governed by cell-intrinsic means and microenvironmental co-adaptation. Although this balance is fundamental for lifelong hematopoiesis and immunity, the underlying molecular mechanisms remain poorly defined. Multimodal analysis divulging differential transcriptional activity between distinct HSPC states indicates the presence of Fli-1 transcription factor binding motif in activated hematopoietic stem cells. We reveal that Fli-1 activity is essential during regenerative hematopoiesis in mice. Fli-1 directs activation programs while priming cellular sensory and output machineries, enabling HSPCs co-adoptability with a stimulated vascular niche through propagation of niche-derived angiocrine Notch1 signaling. Constitutively induced Notch1 signaling is sufficient to recuperate functional hematopoietic stem cells impairments in the absence of Fli-1, without leukemic transformation. Applying FLI-1 transient modified-mRNA transduction into latent adult human mobilized HSPCs, enables their niche-mediated expansion and superior engraftment capacities. Thus, decryption of stem cell activation programs offers valuable insights for immunological regenerative medicine.

Animals

Trajectory inference from single-cell genomics data with a process time model.

Single-cell transcriptomics experiments provide gene expression snapshots of heterogeneous cell populations across cell states. These snapshots have been used to infer trajectories and dynamic information even without intensive, time-series data by ordering cells according to gene expression similarity. However, while single-cell snapshots sometimes offer valuable insights into dynamic processes, current methods for ordering cells are limited by descriptive notions of "pseudotime" that lack intrinsic physical meaning. Instead of pseudotime, we propose inference of "process time" via a principled modeling approach to formulating trajectories and inferring latent variables corresponding to timing of cells subject to a biophysical process. Our implementation of this approach, called Chronocell, provides a biophysical formulation of trajectories built on cell state transitions. The Chronocell model is identifiable, making parameter inference meaningful. Furthermore, Chronocell can interpolate between trajectory inference, when cell states lie on a continuum, and clustering, when cells cluster into discrete states. By using a variety of datasets ranging from cluster-like to continuous, we show that Chronocell enables us to assess the suitability of datasets and reveals distinct cellular distributions along process time that are consistent with biological process times. We also compare our parameter estimates of degradation rates to those derived from metabolic labeling datasets, thereby showcasing the biophysical utility of Chronocell. Nevertheless, based on performance characterization on simulations, we find that process time inference can be challenging, highlighting the importance of dataset quality and careful model assessment.

Single-Cell Analysis

Compartment model approach to the estimation of tumor incidence and growth: investigation of a model of cancer latency.

Consideration is made of the problems involved in determining the effects of a chronic disease process, such as stomach cancer, on the observed mortality of the U.S. population. Specifically, since the time of initiation of tumor growth is unknown and the tumor becomes clinically manifest only after reaching considerable size, the early rate and pattern of tumor growth is unobserved. As a possible solution to the analysis of such problems, it is proposed to use stochastic compartment modelling techniques which deal with the problems of estimating the transition probabilities of a partially observed stochastic process. Implementation of the stochastic compartment techniques in this case depends on the selection of certain mathematical expressions from theories of carcinogenesis, epidemiologic studies and animal studies which allow the calculation of transition probabilities to unobserved states by making them explicit functions of time or age. Though the selection of the specific functions might be subject to debate, the general strategy of explicitly selecting such functions, and thereby exposing them for review in terms of biologic reasonableness and consistency with the data, seems to be a valid and useful methodology. Furthermore, various ways of viewing the model results (say from its internal behavior, e.g., from implied distributions of waiting times in various disease states) yield different insights into the various factors in carcinogenesis. The model, with parameters representing tumor incidence, time to tumor death given onset, genetic susceptibility to tumor growth and the effects of competing forces of mortality, is fitted to data on deaths due to stomach cancer for male U.S. residents age 25 and over in 1969. Two basic forms of the model, one with a waiting time distribution for occupants of the latent state and another with a single latency time, achieved excellent fits to the data. Examination of parameter estimates and compartment waiting time distributions are consistent with theoretical expectations and intuition. It is concluded that such strategies, involving the integration of clinical, experimental and vital statistics data into a comprehensive model of population carcinogenesis, are potentially powerful tools for investigation of the temporal dimensions of disease development in a human population.

Adult

Single-cell capture of on-ART SIV transcription reveals TGF-β-mediated metabolic control of viral latency.

We previously demonstrated that blocking TGF-β with galunisertib, a safe, orally available small drug, reactivated latent SIV in vivo by shifting T cells toward a transitional effector phenotype. Here, we investigated the mechanisms underlying this effect using single-cell RNA sequencing, metabolic profiling, and high-dimensional spectral flow cytometry of samples from SIV-infected, antiretroviral therapy-treated (ART-treated) macaques before and after galunisertib. To characterize virus-transcribing, infected cells during ART, we developed a novel, sensitive SIV Transcripts Capture Assay (SCAP) that detected 127 SIV-expressing cells within lymph node single-cell transcriptome libraries. Galunisertib drove broad metabolic reprogramming in CD4+ T cells, with transcriptional upregulation of inflammatory and mitochondrial biosynthesis pathways, confirmed by Seahorse profiling. Metabolomics revealed increased energy metabolites and amino acids and enhanced metabolic flux without proliferation. SIV transcript-positive cells before galunisertib were metabolically quiescent compared with cells without detectable viral transcripts. After galunisertib, virus-expressing cells showed a dramatic metabolic activation, with upregulation of glycolysis, fatty acid metabolism, and TNF-α signaling. High-dimensional flow cytometry demonstrated effects beyond CD4+ T cells, including fewer tissue-resident memory T cells, but more inflammatory macrophages. In conclusion, SCAP represents a specific tool for characterizing rare SIV-infected cells transcribing virus during ART, and it reveals TGF-β as a key mediator of viral latency in vivo through metabolic suppression.

Virus Latency

[Epileptic manifestations following head injury (author's transl)].

An analysis is presented of the findings in a group of 300 patients with head injury, aged 15 years or over at the time of the accident, who subsequently developed epileptic manifestations. Early fits (including one case of immediate onset) were found in 33% of the cases (99 patients). In contrast to post-traumatic late epilepsy (PTE), which is a manifestation of a static process, early fits are triggered off by a dynamic process (brain oedema, haemorrhage) and are a sign of cerebral irritation, but do not represent a true form of epilepsy. Early fits are related to the acute traumatic state; the time limit is flexible, but lies in the region of 4 weeks following injury. Conversion of early fits to PTE (with or without a latent interval) occurred in 72% of the cases. This percentage is higher than the average incidence quoted in the literature and presumably arises partly from the selection criteria applied in this study. The time of appearance of early fits following injury is one factor which determines the prognosis. Fits appearing on the first day carry a relatively favourable prognosis and do not proceed to PTE in 41% of the cases, whereas this percentage shrinks to 15% in the case of fits appearing from the second week onwards. Early fits are an isolated occurrence in one third of the cases; progression to PTE is less frequent in these patients than following frequent, repeated convulsions. Furthermore, the incidence of early fits is dependent, to a large extent, on traumatological and clinical factors: the combination of unconsciousness of over three hours' duration, neurological signs referable to the central nervous system, persistent organic psychotic syndrome and intracranial bleeding leads to a significantly higher incidence of early fits than unconsciousness of less than three hours' duration and absence of neurological signs in patients who, moreover, do not display features of the psychotic syndrome, and shows a greater tendency to early fits even than the combination of depressed fracture of the skull with penetration of the dura. Should, however, early fits occur in spite of a favourable assessment of the traumatological factors involved, then progression to PTE occurs in a higher percentage of such cases than in patients displaying signs of a serious import following injury. The transition to PTE is markedly higher following diffuse cerebral contusion (75% of cases) than in cases displaying signs of local contusion....

Adult