Search

Summary: Introduction: Collagen type XVIII regulates cellular activities of adjacent cells at the dermal‐epidermal junction (DEJ). To investigate its possible changes during aging, we compared its mRNA levels and protein localization in skin samples from female participants aged 20‐70 years old. In addition, we evaluated the beneficial effects of unripe peach extracts in a 3D skin model. Methods: Sun‐exposed or sun‐protected female skin samples were compared by DNA array or by immunohistochemistry for basement membrane components. To evaluate protective effects of fresh unripe peach extract, UV‐B irradiated human 3D skin models were incubated in the presence or absence of the extract, followed by measurements of mRNA levels by real‐time PCR, or by immunohistochemistry. Results: In aged skin samples, COL18A1 mRNA levels were lower and the protein localization exhibited less intensive signal by anti‐collagen type XVIII immunostaining. As observed in the skin tissues, collagen type XVIII exists at the DEJ in the 3D skin model. Fresh unripe peach extract significantly improved mRNA levels and partially localizations of collagen type XVIII, suggesting that fresh unripe peach extract ameliorates DEJ damages caused by UV‐B irradiation. Conclusion: Collagen type XVIII and fresh unripe peach extract can be promising protective cosmetic strategies against skin aging. [ABSTRACT FROM AUTHOR]

Anatomy is the science and art of understanding the structure of the body and its components in relation to the functions of the whole-body system. Medicine is based on a deep understanding of anatomy, but quite a few introductory-level learners are overwhelmed by the sheer amount of anatomical terminology that must be understood, so they regard anatomy as a dull and dense subject. To help them learn anatomical terms in a more contextual way, we started a new open-source project, the Network of Anatomical Texts (NAnaTex), which visualizes relationships of body components by integrating text-based anatomical information using Cytoscape, a network visualization software platform. Here, we present a network of bones and muscles produced from literature descriptions. As this network is primarily text-based and does not require any programming knowledge, it is easy to implement new functions or provide extra information by making changes to the original text files. To facilitate collaborations, we deposited the source code files for the network into the GitHub repository () so that anybody can participate in the evolution of the network and use it for their own non-profit purposes. This project should help not only introductory-level learners but also professional medical practitioners, who could use it as a quick reference. [ABSTRACT FROM AUTHOR]

We first Completed the primary structure of the mouse α5(IV) and α6(IV) chains, from which synthetic peptides were produced and α chain-specific monoclonal antibodies were raised. Expression of collagen IV genes in various basement membrances underlying specific organ epithelia was analyzed by immunohistochemical staining using these monoclonal antibodies and other antibodies from human and bovine sequences. It was possible to predict the presence of the three collagen IV molecules: [α1 (IV)]2 α2(IV), α3 (IV) α4(IV)α5(IV), and [α5(IV)]2α6(IV), were detected. The α3(IV) α4(IV)α5(IV) molecule was observed as the major from in glomerulus, alveolus, and choroid plexus, where basement membranes function as filtering units. The molecular from [α5(IV)]2α6(IV) was present In basement membranes in tubular organs such as the epididymis where the tubes need to expand in diameter. Thus, the distribution of the basement membranes with different molecular composition is consistent with tissue-specific function. [ABSTRACT FROM AUTHOR]

Six distinct genes have been identified as belonging to the type IV collagen gene family. They can be organized into three sets, i.e., COL4A1/COL4A2, COL4A3/COL4A4, and COL4A5/COL4A6, which are localized on three different chromosomes in humans, 13,2, and X, respectively. Within each set the genes are aligned head-to-head and their expression is regulated by bidirectional promoters between the genes. Transcriptional regulation of the COL4A1/COL4A2 set has been well characterized. The transcription of COL4A6 seems to be controlled by two alternative promoters. While collagen IV molecules composed of α1 and α2 chains are broadly distributed, molecules comprising combinations of the other four chains, α3–α6, are important components of specialized basement membranes. The precise chain composition of triple-helical molecules assembled from the α3–α6 chains is not entirely clear, but it is hypothesized that α3–α5 chains and α5 and α6 chains form heterotrimeric molecules. Several pieces of evidence indicate that α3/α4/α5 molecules and α5/α6 molecules are components of the basement membrane network. This helps explain the observation that the kidney and skin basement membranes from patients with Alport syndrome caused by mutations in the α5 coding gene, COL4A5, are defective in the α3, α4, and α6 chains together with the α5 chain. Large deletions involving the COL4A5 and COL4A6 genes have been found in rare cases of diffuse leiomyomatosis associated with Alport syndrome. [ABSTRACT FROM AUTHOR]

Tachycardia is common in intensive care units (ICUs). It is unknown whether tachycardia or prolonged tachycardia affects patient outcomes. We investigated the association between tachycardia and mortality in critically ill patients. This retrospective cohort study's primary outcome was patient mortality in the ICU and the hospital. We stratified the patients (n=476) by heart rate (HR) as LowHR, MediumHR, and HighHR groups. We also stratified them by their durations of HR >100 (prolonged HR; tachycardia): MildT, ModerateT, and SevereT groups. We determined the six groups' mortality. The ICU mortality rates of the LowHR, MediumHR, and HighHR groups were 1.0%, 1.5%, and 7.9%, respectively; significantly higher in the HighHR vs. LowHR group. The in-hospital mortality rates of these groups were 1%, 4.5%, and 14.6%, respectively; significantly higher in the HighHR vs. LowHR group. The ICU mortality rates of the MildT, ModerateT, and SevereT groups were 0.9%, 5.6%, and 57.1%, respectively. The mortality of the HRT=0 (i.e., all HR ≤ 100) patients was 0%. The in-hospital mortality rates of the MildT, ModerateT, and SevereT groups were 1.8%, 16.7%, and 85.7%, respectively; that of the HRT=0 patients was 0.5%. Both higher HR and prolonged tachycardia were associated with poor outcomes., Competing Interests: No potential conflict of interest relevant to this article was reported.

Type 2 diabetes mellitus is linked to impaired skeletal muscle glucose uptake and storage. This study aimed to investigate the fiber type distributions and the three-dimensional (3D) architecture of the capillary network in the skeletal muscles of type 2 diabetic rats. Muscle fiber type transformation, succinate dehydrogenase (SDH) activity, capillary density, and 3D architecture of the capillary network in the soleus muscle were determined in 36-week-old Goto-Kakizaki (GK) rats as an animal model of nonobese type 2 diabetes and age-matched Wistar (Cont) rats. Although the soleus muscle of Cont rats comprised both type I and type IIA fibers, the soleus muscle of GK rats had only type I fibers. In addition, total SDH activity in the soleus muscle of GK rats was significantly lower than that in Cont rats because GK rats had no high-SDH activity type IIA fiber in the soleus muscle. Furthermore, the capillary diameter, capillary tortuosity, and microvessel volume in GK rats were significantly lower than those in Cont rats. These results indicate that non-obese diabetic GK rats have muscle fiber type transformation, low SDH activity, and reduced skeletal muscle capillary content, which may be related to the impaired glucose metabolism characteristic of type 2 diabetes.

We attempted to prepare colloidal iron within tissues by means of microwave irradiation. Mouse tissue blocks were fixed with a mixture of paraformaldehyde and ferric chloride in a cacodylate buffer, immersed in a cacodylate buffered ferric chloride solution, and irradiated in a microwave processor. Colloidal iron was prepared within tissues or cells, and was observed in the form of electron dense fine granules (1-2 nm in diameter) by transmission electron microscopy. Collagen fibrils in the connective tissue showed colloidal iron deposition at regular periodical intervals. Cells in the splenic tissue showed that fine colloidal granules were deposited on the ribosomes but not on the nuclear chromatin. This finding suggests that ferric ions could not diffuse into the nucleus, which was surrounded by the nuclear envelope. The podocyte processes of the renal glomerulus were stained diffusedly. Though this microwave in situ colloidal iron preparation method has some limitations, it is convenient for use in biomedical specimen preparation in transmission electron microscopy.