The "Viral" Form of Polyarteritis Nodosa (PAN)-A Distinct Entity: A Case Based Review.

Classic polyarteritis nodosa (PAN) is a vasculitis with systemic manifestations that is characterized by inflammatory and necrotizing lesions affecting medium and small muscular arteries, most frequently at the bifurcation of the vessels. These lesions lead to the formation of microaneurysms, hemorrhaging ruptured aneurysms, thrombosis, and, consequently, ischemia or organ infarction. Background and Objectives: We present a complex clinical case of a patient with a late diagnosis of polyarteritis nodosa with multiorgan involvement. Materials and Methods: The 44-year-old patient, in an urban environment, presented on her own in the emergency room for acute ischemia phenomena and forearm and right-hand compartment syndrome, requiring surgical decompression in the Plastic Surgery Clinic. Results: Significant inflammatory syndrome is noted, alongside severe normocytic hypochromic iron deficiency anemia, nitrogen retention syndrome, hyperkalemia, hepatic syndrome, and immunological disturbances: absence of cANCA, pANCA, anti Scl 70 Ac, antinuclear Ac, and anti dDNA Ac, as well as a low C3 fraction of the plasmatic complement system. The morphological aspect described in the right-hand skin biopsy correlated with the clinical data supports the diagnosis of PAN. Conclusions: The viral form of PAN seems to be individualized as a distinct entity, requiring early, aggressive medication.

Loneliness as Cause.

While loneliness has been linked to various mental and physical health problems, the sense in which loneliness is a cause of these conditions has so far attracted little philosophical attention. This paper aims to fill this gap by analyzing research on health effects of loneliness and therapeutic interventions through current approaches to causality. To deal with the problem of causality between psychological, social, and biological variables, the paper endorses a biopsychosocial model of health and disease. I will investigate how three main approaches to causality used in psychiatry and public health apply to loneliness: interventionism, mechanisms, and dispositional theories. Interventionism can specify whether loneliness causes specific effects, or whether a treatment works, incorporating results from randomized controlled trials. Mechanisms help explain how loneliness brings about negative health effects, spelling out psychological processes involved in lonely social cognition. Dispositional approaches help stress particular features of loneliness connected to negative social interactions, such as defensiveness. I will conclude by showing that previous research alongside emerging approaches to health effects of loneliness lend themselves to analysis in terms of the causal models under discussion.

PEX6 Mutation in a Child with Infantile Refsum Disease-A Case Report and Literature Review.

The aim of this paper is to describe the temporal progression and clinical picture of a 2-year-old child with infantile Refsum disease, as well as the diagnostic procedures performed; this case presented multiple hematologic, metabolic, and developmental complications and progressive disabilities. Genetic testing revealed a mutation of the PEX6 (Peroxisomal Biogenesis Factor 6) gene, and the metabolic profile was consistent with the diagnosis. Particularly, the child also presented altered coagulation factors and developed a spontaneous brain hemorrhage. The clinical picture includes several neurological, ophthalmological, digestive, cutaneous, and endocrine disorders as a result of the very long chain fatty acid accumulation as well as secondary oxidative anomalies. The study of metabolic disorders occurring because of genetic mutations is a subject of core importance in the pathology of children today. The PEX mutations, difficult to identify antepartum, are linked to an array of cell anomalies with severe consequences on the patient's status, afflicting multiple organs and systems. This is the reason for which our case history may be relevant, including a vast number of symptoms, as well as modified biological parameters.

The Significance of Low Magnesium Levels in COVID-19 Patients.

Magnesium is the fourth most common mineral in the human body and the second richest intracellular cation. This element is necessary for many physiological reactions, especially in the cardiovascular and respiratory systems. COVID-19 is an infectious disease caused by SARS-CoV-2. The majority of people who become ill as a result of COVID-19 have mild-to-moderate symptoms and recover without specific treatment. Moreover, there are people who develop severe forms of COVID-19, which require highly specialized medical assistance. Magnesium deficiency may play a role in the pathophysiology of infection with SARS-CoV-2. The primary manifestation of COVID-19 remains respiratory, but the virus can spread to other organs and tissues, complicating the clinical picture and culminating in multiorgan failure. The key mechanisms involved in the disease include direct viral cytotoxicity, endothelial dysfunction, and exaggerated release of inflammatory cytokines. The aim of this review was to summarize the available data regarding the role of magnesium in COVID-19 patients and its particularities in different clinical settings.

The Effects of the COVID-19 Pandemic on Mental Health: A Web-Based Study Among Romanian Adults.

Background In Romania, as in other parts of the world, the family doctor is the first to make contact with a healthy patient and is also the first to notice even the smallest pathological changes. In the context of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, the patient's communication with the family doctor became even closer and some behavioral changes could be easily noticed. Objective To assess the symptoms of anxiety and depression in the Romanian population using social media platforms in the context of the COVID-19 pandemic. Methods We conducted an anonymous, web-based cross-sectional survey consisting of 31 questions related to general characteristics (age, gender, education, inhabitancy, residence, smoking status, and alcohol consumption) and adapted GAD-7 (7-item General Anxiety Disorders questionnaire) and PHQ-9 (9-item Patient Health Questionnaire). This questionnaire was sent to volunteers in an electronic format through a social network (Facebook, Twitter). The data collected were statistically processed using IBM SPSS v25.0 (IBM Corp., Armonk, NY). The inclusion criteria were age over 18 years and no history of chronic disease. The exclusion criteria consisted of the absence of a mental illness diagnosis. Results From the 1254 respondents, 1232 cases were selected for statistical analysis after applying the exclusion criteria. The mean age was 35.94 (SD = 11.4, 95%CI=10.9-11.9) with a minimum of 18 years and a maximum of 97 years. Eighty-four point nine percent (84.9%; N=1046) of all study participants are female and 79.13% (N= 975) live in the urban area. A total of 188 (15.25%) were diagnosed with COVID-19 of which 31 (16.66%) were male and 157 (15%) were female. N=170 (13.8%) reported moderate symptoms of anxiety during the last two weeks before the survey while N=96 (7.8%) had severe anxiety. Twenty-two point two percent (22.2%; N=274) of the participants reported moderate symptoms of depression while 10.1% (N=125) had moderately severe symptoms and 6.6% (N=81) could be diagnosed with severe depression. A greater likelihood of screening for depression diagnosis was associated with ages between 25 and 34 years (OR=0.90, 95%CI=0.86-0.94, P<.001), 35 and 44 years (OR=0.88, 95%CI=0.84-0.93, P<.001), and 45 and 54 years (OR=0.87, 95%CI=0.82-0.92, P<.001). Also, a tendency was observed for women to be more prone to high levels of anxiety (OR=1.21, 95%CI=1.08-1.35, P< .001) and depression (OR=2.16, 95%CI=1.51-308, P< .005). Conclusions Regarding the high prevalence of depression and anxiety, especially in women, appropriate measures for the risk categories should be applied. In the new social context created by the COVID-19 pandemic, screening for psychiatric and psychological disorders should be performed by telemedicine.

Loneliness and negative effects on mental health as trade-offs of the policy response to COVID-19.

This note introduces a framework incorporating multiple sources of evidence into the response to COVID-19 to overcome the neglect of social and psychological causes of illness. By using the example of psychological research on loneliness and its effects on physical and mental health with particular focus on aging and disability, I seek to open further inquiry into how relevant psychological and social aspects of health can be addressed at policy level.

Mental health, normativity, and local knowledge in global perspective.

Approaching mental health on a global scale with particular reference to low- and mid-income countries raises issues concerning the disregard of the local context and values and the imposition of values characteristic of the Global North. Seeking a philosophical viewpoint to surmount these problems, the present paper argues for a value-laden framework for psychiatry with the specific incorporation of value pluralism, particularly in relation to the Global South context, while also emphasizing personal values such as the choice of treatment. In sketching out this framework, the paper aims to overcome the clash between universalism and relativism about psychiatric categories by focusing on how overlaps between cultures can contribute to ontology-building. A case study analyzing ethnopsychiatric research in the context of South India will illustrate the proposed view, while also pointing out avenues for further research on the causal efficacy of local shared beliefs about mental disorder. If approaches across different traditions and theoretical frames are shown to work in treating similar ailments, causal connections appear to cut across the different ontologies. Ethnopsychiatry would play a central role in such research, namely in disclosing the variables and mechanisms at work within the local approaches.

Revitalising the rudimentary replacement dentition in the mouse.

Most mammals have two sets of teeth (diphyodont) - a deciduous dentition replaced by a permanent dentition; however, the mouse possesses only one tooth generation (monophyodont). In diphyodonts, the replacement tooth forms on the lingual side of the first tooth from the successional dental lamina. This lamina expresses the stem/progenitor marker Sox2 and has activated Wnt/ß-catenin signalling at its tip. Although the mouse does not replace its teeth, a transient rudimentary successional dental lamina (RSDL) still forms during development. The mouse RSDL houses Sox2-positive cells, but no Wnt/ß-catenin signalling. Here, we show that stabilising Wnt/ß-catenin signalling in the RSDL in the mouse leads to proliferation of the RSDL and formation of lingually positioned teeth. Although Sox2 has been shown to repress Wnt activity, overexpression of Wnts leads to a downregulation of Sox2, suggesting a negative-feedback loop in the tooth. In the mouse, the first tooth represses the formation of the replacement, and isolation of the RSDL is sufficient to induce formation of a new tooth germ. Our data highlight key mechanisms that may have influenced the evolution of replacement teeth.This article has an associated 'The people behind the papers' interview.

Complex patterns of tooth replacement revealed in the fruit bat (Eidolon helvum).

How teeth are replaced during normal growth and development has long been an important question for comparative and developmental anatomy. Non-standard model animals have become increasingly popular in this field due to the fact that the canonical model laboratory mammal, the mouse, develops only one generation of teeth (monophyodonty), whereas the majority of mammals possess two generations of teeth (diphyodonty). Here we used the straw-coloured fruit bat (Eidolon helvum), an Old World megabat, which has two generations of teeth, in order to observe the development and replacement of tooth germs from initiation up to mineralization stages. Our morphological study uses 3D reconstruction of histological sections to uncover differing arrangements of the first and second-generation tooth germs during the process of tooth replacement. We show that both tooth germ generations develop as part of the dental lamina, with the first generation detaching from the lamina, leaving the free edge to give rise to a second generation. This separation was particularly marked at the third premolar locus, where the primary and replacement teeth become positioned side by side, unconnected by a lamina. The position of the replacement tooth, with respect to the primary tooth, varied within the mouth, with replacements forming posterior to or directly lingual to the primary tooth. Development of replacement teeth was arrested at some tooth positions and this appeared to be linked to the timing of tooth initiation and the subsequent rate of development. This study adds an additional species to the growing body of non-model species used in the study of tooth replacement, and offers a new insight into the development of the diphyodont condition.

Versatile SPR aptasensor for detection of lysozyme dimer in oligomeric and aggregated mixtures.

A Surface Plasmon Resonance (SPR) sensor for the quantitation of lysozyme dimer in monomer-dimer mixtures, reaching a detection limit of 1.4nM dimer, has been developed. The sensor is based on an aptamer which, although developed for the monomeric form, binds also the dimeric form but with a strikingly different kinetics. The aptasensor was calibrated using a dimer obtained by cross-linking. Sensorgrams acquired with the aptasensor in monomer-dimer mixtures were analysed using Principal Components Analysis and Multiple Regression to establish correlations with the dimer content in the mixtures. The method allows the detection of 0.1-1% dimer in monomer solutions without any separation. As an application, the aptasensor was used to qualitatively observe the initial stages of aggregation of lysozyme solutions at 60°C and pH 2, through the variations in lysozyme dimer amounts. Several other methods were used to characterize the lysozyme dimer obtained by cross-linking and confirm the SPR results. This work highlights the versatility of the aptasensor, which can be used, by simply tuning the experimental conditions, for the sensitive detection of either the monomer or the dimer and for the observation of the aggregation process of lysozyme.

Is Right Ventricular Remodeling in Pulmonary Hypertension Dependent on Etiology? An Echocardiographic Study.

AIMS: Survival in patients (pts) with pulmonary hypertension (PH) differs between subgroups at similar levels of pressure overload. We set to analyze right ventricular (RV) morphology and function in different types of PH using conventional and deformation imaging echocardiography. MATERIAL AND METHODS: Thirty-four pts with PH: 12 pts with idiopathic pulmonary arterial hypertension (IPAH, 42.2 ± 13 years), 11 pts with chronic thromboembolic PH (CTEPH, 50.8 ± 12 years), 11 pts with Eisenmenger syndrome [ES 41.2 ± 15 years, 4 with atrial septal defect (ASD) and 7 with ventricular septal defect (VSD)], and 13 age-matched healthy individuals (38.1 ± 15 years) were evaluated. The following echocardiographic parameters were measured: echo-derived systolic pulmonary pressure (sPAPecho), RV end-diastolic diameter (RVEDD), RV wall thickness (RVWT), TAPSE, RV fractional area change (RVFAC), Tei index, peak systolic velocity of the tricuspid ring (S't), and speckle tracking-derived RV free wall strain. Furthermore, right heart catheterization (RHC) was performed in pts with PH and mean, and systolic pulmonary artery pressure (mPAPcath, sPAPcath), cardiac output (CO), cardiac index (COi), and pulmonary vascular resistance (PVR) were noted. RESULTS: The levels of mPAPcath and sPAPcath were similar between pts with PH (pANOVA = NS). Patients with ES had higher COi compared to other groups (2.94 ± 0.79, 2.28 ± 0.69, and 1.74 ± 0.46 L/min/m(2) for pts with ES, IPAH, and CTEPH respectively, pANOVA = 0.004, P post hoc ES versus all other groups < 0.05). TAPSE, Tei index, and S't were similar between groups and impaired versus controls (pANOVA < 0.001, P post hoc between groups of patients = NS). Patients with ES had better RVFAC (41.1 ± 9, 30.5 ± 10.8, 23.2 ± 9.8%) and RV free wall strain (-20.6 ± 3.5, -16.3 ± 7.5, -10.8 ± 5%), as well as an increased thickness of the RV free wall compared to other groups of patients (9.2 ± 1.5, 7.2 ± 1 and 7.2 ± 1.6 mm for pts with ES, IPAH and CTEPH, respectively) (pANOVA<0.001, P post hoc <0.05 ES versus all other groups). RVFAC and RV free wall strain significantly correlated with COi (r = 0.53, P = 0.006 and r = -0.77, P < 0.001, respectively). CONCLUSION: Patients with ES have a more hypertrophied RV free wall, better RV performance as assessed by RVFAC and RV free wall strain and increased COi compared to other types of PH. Furthermore, RV performance appears to be less dependent on the level of pressure overload. These findings could contribute to the better survival profile of patients with ES.

Magnetically-Responsive Hydrogels for Modulation of Chondrogenic Commitment of Human Adipose-Derived Stem Cells.

Magnetic nanoparticles (MNPs) are attractive tools to overcome limitations of current regenerative medicine strategies, demonstrating potential to integrate therapeutic and diagnostic functionalities in highly controlled systems. In traditional tissue engineering (TE) approaches, the MNPs association with stem cells in a three-dimensional (3D) template offers the possibility to achieve a mechano-magnetic responsive system, enabling remote control actuation. Herein, we propose to study the role of MNPs integrated in κ-carrageenan (κC) hydrogels in the cellular response of human adipose-derived stem cells (hASCs) aiming at cartilage TE applications. The results indicated that the concentration of MNPs in the κC hydrogels influences cellular behavior, tuning a positive effect on cell viability, cell content and metabolic activity of hASCs, with the most promising outcomes found in 5% MNP-κC matrices. Although hASCs laden in MNPs-free- and MNPs-κC hydrogels showed similar metabolic and proliferation levels, MNPs κC hydrogels under magnetic actuation evidenced an instructive effect on hASCs, at a gene expression level, towards chondrogenic phenotype even in basic medium cultures. Therefore, the MNPs-based systems developed in this study may contribute to advanced strategies towards cartilage-like engineered substitutes.

Epithelial topography for repetitive tooth formation.

During the formation of repetitive ectodermally derived organs such as mammary glands, lateral line and teeth, the tissue primordium iteratively initiates new structures. In the case of successional molar development, new teeth appear sequentially in the posterior region of the jaw from Sox2(+) cells in association with the posterior aspect of a pre-existing tooth. The sequence of molar development is well known, however, the epithelial topography involved in the formation of a new tooth is unclear. Here, we have examined the morphology of the molar dental epithelium and its development at different stages in the mouse in vivo and in molar explants. Using regional lineage tracing we show that within the posterior tail of the first molar the primordium for the second and third molar are organized in a row, with the tail remaining in connection with the surface, where a furrow is observed. The morphology and Sox2 expression of the tail retains characteristics reminiscent of the earlier stages of tooth development, such that position along the A-P axes of the tail correlates with different temporal stages. Sox9, a stem/progenitor cell marker in other organs, is expressed mainly in the suprabasal epithelium complementary with Sox2 expression. This Sox2 and Sox9 expressing molar tail contains actively proliferating cells with mitosis following an apico-basal direction. Snail2, a transcription factor implicated in cell migration, is expressed at high levels in the tip of the molar tail while E-cadherin and laminin are decreased. In conclusion, our studies propose a model in which the epithelium of the molar tail can grow by posterior movement of epithelial cells followed by infolding and stratification involving a population of Sox2(+)/Sox9(+) cells.

Natural assembly of platelet lysate-loaded nanocarriers into enriched 3D hydrogels for cartilage regeneration.

The role of Platelet Lysates (PLs) as a source of growth factors (GFs) and as main element of three-dimensional (3D) hydrogels has been previously described. However, the resulting hydrogels usually suffer from high degree of contraction, limiting their usefulness. This work describes the development of a stable biomimetic 3D hydrogel structure based on PLs, through the spontaneous assembling of a high concentration of chitosan-chondroitin sulfate nanoparticles (CH/CS NPs) with PLs loaded by adsorption. The interactions between the NPs and the lysates resemble the ones observed in the extracellular matrix (ECM) native environment between glycosaminoglycans and ECM proteins. In vitro release studies were carried out focusing on the quantification of PDGF-BB and TGF-ß1 GFs. Human adipose derived stem cells (hASCs) were entrapped in these 3D hydrogels and cultured in vitro under chondrogenic stimulus, in order to assess their potential use for cartilage regeneration. Histological, immunohistological and gene expression analysis demonstrated that the PL-assembled constructs entrapping hASCs exhibited results similar to the positive control (hASCS cultured in pellets), concerning the levels of collagen II expression and immunolocalization of collagen type I and II and aggrecan. Moreover, the deposition of new cartilage ECM was detected by alcian blue and safranin-O positive stainings. This work demonstrates the potential of PLs to act simultaneously as a source/carrier of GFs and as a 3D structure of support, through the application of a "bottom-up" approach involving the assembly of NPs, resulting in an enriched construct for cartilage regeneration applications.

Seaweed polysaccharide-based hydrogels used for the regeneration of articular cartilage.

This manuscript provides an overview of the in vitro and in vivo studies reported in the literature focusing on seaweed polysaccharides based hydrogels that have been proposed for applications in regenerative medicine, particularly, in the field of cartilage tissue engineering. For a better understanding of the main requisites for these specific applications, the main aspects of the native cartilage structure, as well as recognized diseases that affect this tissue are briefly described. Current available treatments are also presented to emphasize the need for alternative techniques. The following part of this review is centered on the description of the general characteristics of algae polysaccharides, as well as relevant properties required for designing hydrogels for cartilage tissue engineering purposes. An in-depth overview of the most well known seaweed polysaccharide, namely agarose, alginate, carrageenan and ulvan biopolymeric gels, that have been proposed for engineering cartilage is also provided. Finally, this review describes and summarizes the translational aspect for the clinical application of alternative systems emphasizing the importance of cryopreservation and the commercial products currently available for cartilage treatment.

Chondrogenic potential of injectable κ-carrageenan hydrogel with encapsulated adipose stem cells for cartilage tissue-engineering applications.

Due to the limited self-repair capacity of cartilage, regenerative medicine therapies for the treatment of cartilage defects must use a significant amount of cells, preferably applied using a hydrogel system that can promise their delivery and functionality at the specific site. This paper discusses the potential use of κ-carrageenan hydrogels for the delivery of stem cells obtained from adipose tissue in the treatment of cartilage tissue defects. The developed hydrogels were produced by an ionotropic gelation method and human adipose stem cells (hASCs) were encapsulated in 1.5% w/v κ-carrageenan solution at a cell density of 5 × 10(6) cells/ml. The results from the analysis of the cell-encapsulating hydrogels, cultured for up to 21 days, indicated that κ-carrageenan hydrogels support the viability, proliferation and chondrogenic differentiation of hASCs. Additionally, the mechanical analysis demonstrated an increase in stiffness and viscoelastic properties of κ-carrageenan gels with their encapsulated cells with increasing time in culture with chondrogenic medium. These results allowed the conclusion that κ-carrageenan exhibits properties that enable the in vitro functionality of encapsulated hASCs and thus may provide the basis for new successful approaches for the treatment of cartilage defects.

Epidemiological study of metabolic syndrome and risk of diabetes mellitus in a rural family medicine practice in Bacau County.

AIM: This descriptive epidemiological study included 615 subjects investigated by their family doctor in the interval October 2011- August 2012. MATERIAL AND METHODS: Patients were selected according to 2012 IDF diagnostic criteria resulting 304 patients. RESULTS: There was a Gaussian distribution of waist circumference (WC) with a maximum in age-group 70-80 years (46.3%), followed by age- groups 50-60 years (37.8%) and 60-70 years (41.6%). Waist circumference measurement showed an average of 100.76 +/- 11.59 cm, ranges 72 cm - 134 cm, without statistical significance. Mean body mass index (BMI) was 28.25 +/- 4.72 kg/m2 vs. 27.79 +/- 4.48 kg/m2. The difference is statistically significant (p = 0.05). Considering categorical the patients with hypertension (AHT) according to the definition, we found that only 7 cases did not have AHT (4.4%) as compared to a prevalence of AHT of 13.7% in the MS (metabolic syndrome) group. Mean serum triglyceride level was 123.11 +/- 68.55 mg/dl versus 113.75 +/- 65.62 mg/dl in the MS group, significantly higher (p < 0.003). Mean HDL cholesterol was 57.58 +/- 17.11 mg/dl versus 58.54 +/- 15.02 mg/dl, statistically significant difference (p < 0.05). CONCLUSIONS: The prevalence of glucoregulation disorders is higher in the MS group. Proportional relationships were found between BMI, WC, and SBP and high blood glucose. Comparison of blood glucose levels at baseline and at 1 year follow up showed significant differences.

Molecular variants of human papilloma virus 16 E2, E4, E5, E6 and E7 genes associated with cervical neoplasia in Romanian patients.

The aim of this study was to identify and associate the sequence variations of human Papillomavirus 16 (HPV16) genes from women who live in two different areas of Romania and associate them with malignant progression. One hundred twenty-four HPV16-positive cervical isolates were collected, and the E2, E4, E5, E6 and E7 viral genes were sequenced. Two new missense mutations in the E6 gene (C279G and A305C) were found (together or alone, in association with other mutations) in 44 of 124 cases. The most frequently simultaneously mutated genes were E4/E2 hinge, E5 and E6 (p = 0.0004) in squamous cell carcinoma (SCC) samples. Also, for SCC patients, the best-correlated mutation patterns were obtained for E4/E2 hinge-E5 (r = 0.7984; p < 0.0001). No sample was found to have all of the investigated viral genes concurrently mutated. Phylogenetic analysis was performed to characterize the viral variants. Similar results were found for SCC and cervical intraepithelial neoplasia III (CINIII) cases. After all of the target gene sequences were assembled, all patients were found to be infected with viruses of the HPV16- European-German (EG) lineage, and two clusters were identified, the first (55/96 variants) from Moldavia and the second (41/96 variants) from Bucharest. The distinct cluster derived from EG in Moldavia could partially explain the increased frequency of SCC in this area. This study has generated a comprehensive set of sequence variation data on HPV16 circulating in Romania to join the existing data and highlight the important role of HPV16 variants during cervical carcinogenesis.

Fabrication of endothelial cell-laden carrageenan microfibers for microvascularized bone tissue engineering applications.

Recent achievements in the area of tissue engineering (TE) have enabled the development of three-dimensional (3D) cell-laden hydrogels as in vitro platforms that closely mimic the 3D scenario found in native tissues. These platforms are extensively used to evaluate cellular behavior, cell-cell interactions, and tissue-like formation in highly defined settings. In this study, we propose a scalable and flexible 3D system based on microsized hydrogel fibers that might be used as building blocks for the establishment of 3D hydrogel constructs for vascularized bone TE applications. For this purpose, chitosan (CHT) coated κ-carrageenan (κ-CA) microfibers were developed using a two-step procedure involving ionotropic gelation (for the fiber formation) of κ-CA and its polyelectrolyte complexation with CHT (for the enhancement of fiber stability). The performance of the obtained fibers was assessed regarding their swelling and stability profiles, as well as their ability to carry and, subsequently, promote the outward release of microvascular-like endothelial cells (ECs), without compromising their viability and phenotype. Finally, the possibility of assembling and integrating these cell-laden fibers within a 3D hydrogel matrix containing osteoblast-like cells was evaluated. Overall, the obtained results demonstrate the suitability of the microsized κ-CA fibers to carry and deliver phenotypically apt microvascular-like ECs. Furthermore, it is shown that it is possible to assemble these cell-laden microsized fibers into 3D heterotypic hydrogels constructs. This in vitro 3D platform provides a versatile approach to investigate the interactions between multiple cell types in controlled settings, which may open up novel 3D in vitro culture techniques to better mimic the complexity of tissues.