3D reconstruction of peripheral nerves from optical projection tomography images: A method for studying fascicular interconnections and intraneural plexuses

The general microscopic characteristics of nerves are described in several textbooks of histology, but the specific microanatomies of most nerves that can be blocked by anesthesiologists are usually less well known. Our objective was to evaluate the 3D reconstruction of nerve fascicles from optical projection tomography images (OPT) and the ability to undertake an internal navigation exploring the morphology in detail, more specifically the fascicular interconnections. Median and lingual nerve samples were obtained from five euthanized piglets. OPT images of the samples were acquired and 3D reconstruction was performed. The OPT technique revealed the inner structure of the nerves at high resolution, including large and small fascicles, perineurium, interfascicular tissue, and epineurium. The fascicles were loosely packed inside the median nerve and more densely so in the lingual nerve. Analysis of the 3D models demonstrated that the nerve fascicles can show six general spatial patterns. Fascicular interconnections were clearly identified. The 3D reconstruction of nerve fascicles from OPT images opens a new path for research into the microstructure of the inner contents of fascicular nerve groups and their spatial disposition within the nerve including their interconnections. These techniques enable 3D images of partial areas of nerves to be produced and could became an excellent tool for obtaining data concerning the 3D microanatomy of nerves, essential for better interpretation of ultrasound images in clinical practice and thus avoiding possible neurological complications. Clin. Anat. 31:424–431, 2018. © 2017 Wiley Periodicals, Inc.     

Cytocompatibility of novel extracellular matrix protein analogs of biodegradable polyester polymers derived from α-hydroxy amino acids

One of the challenges in regenerative medicine is the development of novel biodegradable materials to build scaffolds that will support multiple cell types for tissue engineering. Here we describe the preparation, characterization, and cytocompatibility of homo- and hetero-polyesters of α-hydroxy amino acid derivatives with or without lactic acid conjugation. The polymers were prepared by a direct condensation method and characterized using gel permeation chromatography, ¹H-nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, optical activity, and solubility. The surface charge of the polymers was evaluated using zeta potential measurements. The polymers were coated onto glass cover slips followed by characterization using nano-surface profiler, thin film reflectometry, and atomic force microscopy (AFM). Their interaction with endothelial and neuronal cells was assessed using adhesion, proliferation, and differentiation assays. Of the characterized polymers, Poly-HOVal-LA, but not Poly-(D)HOPhe, significantly augmented nerve growth factor (NGF)-induced neuronal differentiation of the PC12 pheochromcytoma cells. In contrast, Poly-HOLeu increased by 20% the adhesion of endothelial cells, but did not affect PC12 cell differentiation. NGF-induced Erk1/2 phosphorylation in PC12 cells grown on the different polymers was similar to the effect observed for cells cultured on collagen type I. While no significant association could be established between charge and the differentiative/proliferative properties of the polymers, AFM analysis indicated augmentation of NGF-induced neuronal differentiation on smooth polymer surfaces. We conclude that overall selective cytocompatibility and bioactivity might render α-hydroxy amino acid polymers useful as extracellular matrix-mimicking materials for tissue engineering.     

Eleven consecutive years of respiratory syncytial virus outbreaks in Croatia

Background:  Respiratory syncytial virus (RSV) is the most common cause of severe lower respiratory tract infections (LRTI) in infants. The aim of the present study was to analyze the epidemiologic characteristics of RSV outbreaks in Croatian children.
Methods:  Over a period of 11 consecutive years (1994–2005), 3435 inpatients with acute respiratory infections (ARI) aged from birth to 10 years and were residing in Zagreb County were tested for infection with RSV and other respiratory viruses at the Virology Department, Croatian National Institute of Public Health. RSV was identified in nasopharyngeal secretions by isolation on cell culture and/or detection with monoclonal antibodies using a direct fluorescence assay.
Results:  RSV was the most common causative agent of ARI (42.2%; 658/1559) for the infants 0–6 months of age. It was also the etiologic agent of LRTI in 49% (495/1010) of infants of similar age. RSV was demonstrated in 56.5% (382/676) of infants with bronchiolitis, and in 36.5% (49/134) of those with pneumonia in this age group.
Conclusion:  The overall prevalence of RSV infection in Croatian children with acute respiratory illness, and its occurrence in various age groups, has remained stable over the past decade. RSV was found to be the most common cause of bronchiolitis occurring throughout childhood (52.7%; 482/913).     

Clinical and molecular genetic findings in a 6-year-old Bosnian boy with triple A syndrome

The triple A syndrome is a rare autosomal recessive disease that is characterised by the triad of adrenocorticotropin (ACTH)-resistant adrenal insufficiency, achalasia and alacrima. In most patients, neurological and dermatological abnormalities are associated features. We report on the first Bosnian patient with triple A syndrome. Endocrine investigation confirmed primary adrenal insufficiency at the age of 5.8 years. Two months lather, achalasia was diagnosed, and in the presence of alacrima, the patient satisfies the diagnostic criteria of triple A syndrome. In addition, a large number of associated neurological and dermatological features were present in this patient. Moreover, he has dysmorphic facial features, which have not been previously described in triple A syndrome. Triple A syndrome was confirmed by molecular analysis, revealing a nonsense mutation p.W84X in the AAAS gene. The parents are both heterozygous carriers of the mutation. The affected twin brother unfortunately died from hypoglycaemic shock, despite a normal cortisol rise in an ACTH stimulation test. Further, triple A syndrome patients carrying the identical homozygous p.W84X mutation have to be studied to assess a genotype–phenotype relationship for this mutation. Publication of these pictures was granted by the parents of the patient.     

Plasma ghrelin concentration is a signal of decreased fat free mass in healthy elderly females

This study aimed to evaluate whether circulating ghrelin is associated with changes in different body composition parameters over a 12‐month prospective study period in healthy older females. On 41 postmenopausal women (mean age: 71.0 ± 6.5 years), ghrelin, leptin, insulin resistance (IR), and body composition parameters were assessed before and after the study period. Trunk fat: leg fat ratio (+3.6%), fat free mass (FFM) (?4.1%), glucose (+5.8%), and IR (+7.0%) were significantly changed (P < 0.05), whereas no changes in height, body mass, body mass index, fat mass (FM), %FM, trunk fat, leptin, ghrelin, and insulin were observed as a result of study period. At baseline, ghrelin correlated negatively (r > ?0.306; P < 0.05) with body mass, FM, %FM, trunk fat, FFM, leptin, insulin, and IR. Multivariate linear regression analysis demonstrated that baseline ghrelin concentration was significantly associated only with the mean change in FFM value over the 12‐month study period. In conclusion, basal ghrelin concentration predicted the loss of FFM in healthy elderly females. In addition, these results suggest that circulating ghrelin concentration could be regarded as a signal of decreased FFM in healthy elderly females. Am. J. Hum. Biol., 2009. © 2009 Wiley‐Liss, Inc.     

Serosurvey of human metapneumovirus infection in Croatia

Aim

To assess the seroprevalence of human metapneumovirus (hMPV) in Croatia.

Methods

During 2005, a total of 137 serum specimens from Croatian patients aged from 6 days to 51 years, without respiratory symptoms, were collected at the Croatian National Institute of Public Health. The sera were examined using the indirect immunofluorescent assay.

Results

The overall hMPV seropositivity rate in the samples tested was 77.4% (106/137). The seropositivity rate increased from 18.7% in children aged between 6 months and 1 year to 100% in people older than 20 years of age. The highest proportion of titers ≥1:512 was found in children aged from 1 to 2 years.

Conclusion

Our results suggest that hMPV infection is present in Croatia, with primary infection occurring in early childhood. This is the first study that indicates the circulation of hMPV in Croatia.Human metapneumovirus (hMPV) is a newly discovered respiratory virus assigned to the Paramyxoviridae family, Pneumovirinae subfamily, Metapneumovirus genus. It was first isolated in 2001 from nasopharyngeal aspirates obtained from young children in the Netherlands (1). Sequence analysis of several isolates identified two major genetic lineages (subtypes A and B) that can be further divided into subgroups A1, A2, B1, and B2 (2). HMPV causes acute respiratory tract infections in all age groups (3,4). In hospitalized young children, hMPV infection is commonly present as bronchiolitis with or without pneumonitis (5,6), whereas bronchitis, bronchospasm, and pneumonitis are most commonly seen in elderly patients (3). Since the initial report, hMPV has been studied all over the world and it has been reported on all continents (7). Seroprevalence surveys from the Netherlands (1), Japan (8), and Israel (9) indicated that virtually all children are infected by 5-10 years of age. The aim of this study was to demonstrate the presence of hMPV infection in Croatia, by examining sera from Croatian people for specific anti-hMPV antibodies by an indirect immunofluorescent assay (IFA).     

Cytogenetic aberrations in spontaneous endometrial adenocarcinomas in the BDII rat model as revealed by chromosome banding and comparative genome hybridization

Female rats of the inbred strain BDII are genetically predisposed to endometrial estrogen-dependent adenocarcinomas (EAC). More than 90% of them spontaneously develop this tumor type before the age of 24 months. In order to dissect out the genetic components behind these tumors we have made crosses between BDII females and rats from 2 other strains that are nonsusceptible to EAC. It was found that EAC tumors developed in a subset of intercross and backcross animals from both interstrain crosses. The chromosomal changes in the developing tumors were studied using cytogenetic and molecular cytogenetic methods. From these studies, we conclude that certain chromosome regions were recurrently engaged in chromosomal changes such as increases in copy number (e.g., trisomy, amplification) or decreases (e.g., deletion). Based on the analysis of 56 tumors, 8 regions were found to be particularly often involved: RNO4prx, gain=34 (61%) (amplification 12 cases); RNO5mid, loss=15 (27%); RNO6prx, gain=25 (45%) (amplification 8 cases); RNO10 loss, prx-mid/gain dst=25 (45%) (amplification 1 case); RNO12q, gain=23 (41%); RNO15p loss/RNO15q gain=29 (52%) (amplification 1 case) [RNO, rat chromosome; prx, proximal; mid, middle; dst, distal; p, short arm; q, long arm]. We begun to analyze these regions in detail using various molecular methods and within them there are certain possible target genes, such as MET (RNO4q21), CDKN2A/2B (RNO5q32), MYCN (RNO6q15 approximately q16), and TP53 (RNO10q24 approximately q25), but it is clear that several other genes, still unidentified, must also be involved.     

Unusual distribution pattern of telomeric repeats in the shrews <Emphasis Type="Italic">Sorex araneus</Emphasis> and <Emphasis Type="Italic">Sorex granarius</Emphasis>

Sorex araneus and Sorex granarius are sibling species within the Sorex araneus group with karyotypes composed of almost identical chromosome arms. S. granarius has a largely acrocentric karyotype, while, in S. araneus, various of these acrocentrics have combined together by Robertsonian (Rb) fusions to form metacentrics, with the numbers and types of metacentrics differing between chromosomal races. Our studies on telomeric sequences in S. araneus and S. granarius revealed differences between chromosomes and between species. In S. araneus (the Novosibirsk race), hybridization signals were present on the telomeres of all the chromosomes after FISH with a PCR-generated telomeric probe. In addition, hybridization signals were observed at high frequencies in the pericentric regions of some but not all metacentrics formed by Rb fusion. There were fewer signals on those metacentrics formed earlier in the evolution of S. araneus. This suggests that S. araneus chromosomes retain at least some telomeric repeats during Rb fusion, but that these repeats are lost or modified over time. These results are critical for the interpretation of the well-studied hybrid zones between chromosomal races of S. araneus, given that Rb fission has been postulated in such hybrid zones and that the likelihood of Rb fission will relate to presence/absence of telomeric sequences at the centromeres of metacentrics. In S. granarius, there were strong signals at the proximal (centromeric) telomeres of the acrocentrics after FISH with a DNA telomeric probe. FISH with a PNA telomeric probe on S. granarius acrocentrics showed that the proximal telomeres were 213 kb on average, while the length of the distal telomeres was 3.8 kb on average. Two-colour FISH, using a telomeric DNA probe and a microdissected probe generated from the pericentric regions of the S. granarius chromosomes a and b, revealed regions on distinct chromatin fibres where telomeric and microdissected probes were colocalized or localized sequentially. The proximal telomeres of S. granarius are highly unusual both in their large size and their heterogeneous structure relative to the telomeres of other mammals.