Skeletal muscle includes satellite cells, which reside beneath the muscle fiber basal lamina and mainly represent committed myogenic precursor cells, and multipotent stem cells of unknown origin that ...are present in muscle connective tissue, express the stem cell markers Sca-1 and CD34, and can differentiate into different cell types. We tracked bone marrow (BM)-derived stem cells in both muscle connective tissue and satellite cell niches of irradiated mice transplanted with green fluorescent protein (GFP)-expressing BM cells. An increasing number of GFP
+ mononucleated cells, located both inside and outside of the muscle fiber basal lamina, were observed 1, 3, and 6 months after transplantation. Sublaminal cells expressed unambiguous satellite cell markers (M-cadherin, Pax7, NCAM) and fused into scattered GFP
+ muscle fibers. In muscle connective tissue there were GFP
+ cells located close to blood vessels that expressed the
ScaI or CD34 stem-cell antigens. The rate of settlement of extra- and intralaminal compartments by BM-derived cells was compatible with the view that extralaminal cells constitute a reservoir of satellite cells. We conclude that both muscle satellite cells and stem cell marker-expressing cells located in muscle connective tissue can derive from BM in adulthood.
We aimed to measure barriers to accessing abortion care in Indiana, a state with hostile abortion policies that is anticipated to become even more restrictive.
Between June 2021 and April 2022, we ...recruited pregnant Indiana residents seeking abortion via Google advertisements and other online posts, as well as through abortion clinic waiting rooms and callers to local abortion funds. Participants completed a self-administered, online survey at baseline, and a follow-up survey approximately one month later to ascertain outcomes. We compared the proportion of people who reported an abortion at endline by recruitment method and social and economic barriers experienced, using chi-square tests of independence and multivariable logistic regression models.
Overall, 351 participants completed the baseline survey and 205 (58%) participants completed endline. Among those recruited from Google ads, 46% had an abortion compared to 91% and 94% of participants recruited from an abortion fund or a clinic (p<0.01). Participants who reported experiencing abortion stigma — specifically, their family opposed abortion or they feared clinic protestors — (76% vs. 87%), who did not have paid jobs (76% vs. 88%), and were uninsured (65% vs. 86%) were less likely to have received an abortion than were those who did not report these experiences.
Anti-abortion sentiment and financial barriers prevented people from obtaining abortion care in Indiana, while abortion funds facilitated access. As abortion becomes increasingly restricted and likely clinically inaccessible in Indiana, facilitating connections to abortion funds and combating abortion stigma are critical strategies to ensure access to care.
We aimed to understand Indiana residents’ experiences and preferences regarding self-managed abortion in a highly restrictive state.
Between June 2021 and April 2022, we recruited pregnant people who ...lived in Indiana and were considering abortion through Google advertisements, online posts, abortion clinics, and abortion funds. Respondents completed a self-administered online survey at baseline and a second survey one month later. We analyzed reported self-managed abortion experiences at baseline and endline, and characteristics of those who self-managed an abortion.
Among 370 baseline respondents, 66 (18%) reported a preference for self-managed medication abortion over clinical care, while 33 (9%) participants reported an actual attempt to self-manage an abortion for the current pregnancy, and an additional four (1%) were in the process of self-managing. Most who self-managed identified as White (58%), 33% as Black, and 6% as Asian; and were aged 16–37, with pregnancies from 4 to 13 weeks’ gestation. Sixteen (49%) respondents used herbs, six (18%) used misoprostol and/or mifepristone, six (18%) used other medications, two (6%) took emergency contraception after confirming the pregnancy, and 12 (37%) used other methods (eg, caffeine, physical exertion). At endline, 13 (3%) respondents reported ending their pregnancy using self-managed medication abortion. The most common reason given for self-managing an abortion was the inability to pay for clinical care.
Indiana residents need financial support to access clinical abortion care when that is their preference, and need information on safe, effective methods of self-managed medication abortion as an option, particularly in light of anticipated further restrictions on abortion access in the coming year.
Given Indiana's highly restrictive policy context with regard to abortion, and anticipated increases in restrictions, we aimed to measure residents’ experiences traveling out of state for abortion ...care.
Between June 2021 and April 2022, we recruited pregnant people who lived in Indiana and were considering abortion through Google advertisements, abortion clinics, and abortion funds. Respondents completed a self-administered online survey at baseline and a second survey one month later. We analyzed characteristics and experiences of those who reported leaving the state to obtain abortion care.
Among 213 participants who reported an abortion at endline, 56 (26%) left the state to obtain abortion care. These travelers were aged 15–39 with pregnancies from 6 to 31 weeks’ gestation, 71% were parents; and 25 (45%) identified as Black, 23 (41%) as White, and five (9%) as multi-racial. Participants traveled to Illinois most commonly (70%), followed by Kentucky (12%), Ohio (4%), and two other states. The most common barriers experienced by travelers included gathering money (68%), traveling a long distance to the clinic (27%), taking time off (23%), not knowing where to go (21%), arranging childcare (20%), and having difficulty complying with waiting periods and gestational restrictions, and facing clinic protestors. Facilitators included financial support from an abortion fund (63%), easily accessible online information (43%), and financial support from a clinic-based abortion fund (30%).
As more Indiana residents are forced to leave the state for abortion care, investing in abortion funds and practical support services will be essential strategies for maintaining access to abortion care across state lines.
Background:
End‐stage of human dilated cardiomyopathy (DCM) is characterized by myocyte loss and fibrosis, and associated with ventricular dilatation and reduced cardiac function. Matrix ...metalloproteinases (MMPs) and their natural tissue inhibitors (TIMPs) have been involved in the myocardial remodeling.
Aims:
To evaluate the potential role of matrix gelatinases (MMP‐2 and MMP‐9) in DCM, the balance between gelatinases and TIMPs and the gelatinase localization were investigated in left free wall ventricles from six normal donors and six patients with DCM at the transplantation time.
Methods:
TIMP‐(1, 2, 3 and 4) mRNAs were analyzed by quantitative reverse transcription‐polymerase chain reaction (RT‐PCR). TIMP‐1 and ‐2 protein content was assessed by ELISA. MMP‐2 and MMP‐9 expression were examined by zymography and immunological techniques.
Results:
All TIMPs were down‐regulated in DCM hearts, especially TIMP‐1 (reduced by 80%). Gel zymography revealed similar activity of MMP‐2 and MMP‐9 in both tissues. By in situ zymography and immunohistochemistry, active and immunoreactive gelatinases were pericardiomyocyte in control hearts and intracardiomyocyte in DCM hearts. Intracellular MMPs were associated with sarcomeric structure in DCM. To estimate a putative role of these gelatinases, several sarcomeric contractile proteins were digested in vitro by purified active MMP‐9. Only myosin‐heavy chain was cleaved in vitro giving 180‐, 120‐, 80‐ and 20‐kDa proteolytic fragments. In vivo, two major myosin‐heavy chain proteolytic fragments (80 and 20 kDa) were detected by specific monoclonal antibody against myosin‐heavy chain in DCM left ventricular homogenates, only.
Conclusions:
Taken together, these data highly suggest that MMP‐2 and MMP‐9 may be involved in the disorganization of the contractile apparatus in DCM hearts.
Motoneuronal degenerative diseases are characterized by their progressivity; once affected, the motoneurons remain in altered states during an intermediate phase of degeneration prior to their final ...disappearance. Whether this survival period coincides with active metabolic rearrangements in the affected neuron remains unknown. As a first step toward the elucidation of this question, we developed cDNA pooled samples obtained from degenerating and control motoneuron mRNA populations through cellular patch sampling and RT-PCR, using the murine wobbler mutant as a model of spinal atrophy. Hybridization of the cDNA pools to various markers of intact or degenerating motoneurons allowed us to verify the cellular specificity of the patch sampling and indicated conservation of the original mRNA population complexity. Exploration of transcriptional alterations of genes encoding growth factors thought to be involved in motoneuronal development revealed that gene expression of the neurotrophin BDNF was induced in affected motoneurons, while expression of neurotrophin-3 was present in both neuronal types. Likewise, expression of a member of the epidermal growth factor (EGF) family, the neuregulin transcript sensory motor neuron-derived factor, was detected in both control and degenerating motoneurons, while transforming growth factor alpha, the functional homolog of EGF, was present only in the affected motoneurons. Immunohistochemical detection of corresponding proteins corroborated these observations. These results demonstrate that, during the course of their degeneration, motoneurons can initiate expression of novel genes which lead to the production of molecules endowed with trophic and/or differentiative properties for the neurons themselves and their glial environment. They also validate the use of the developed cDNA pooled samples for further exploration of transcriptional alterations taking place in degenerating motoneurons.
This work evaluated thinning strategies in uneven-aged Norway spruce forest stands using a tree distance dependant growth model. The model is based on competition for light between trees demonstrated ...through interception of light rays by individual crowns. It was adapted to mountain settings by analyzing the effect of slope and aspect on light distribution. Growth functions were built by empirically comparing height and diameter increments with age and light availability. A maximum number of new trees set by the user was added each year and mortality, i.e. disappearance of trees not receiving enough light to survive was also included. The model is part of the CAPSIS software package which provides a user-friendly interface for silvicultural simulations. First, thinning typical of current practices in uneven-aged Norway spruce stands in the northern French Alps was simulated. This thinning appeared to be neutral in terms of wood production and beneficial but not dynamic enough in terms of stand renewal. In a second experiment, we compared group selection to individual selection in a virtual two-layered stand organized into clumps. This showed that individual selection favors the growth of the largest trees in the stand while group selection favors the growth of the smaller ones as well as regeneration. In a third simulation, we generated a strategy to convert an even-aged stand into an uneven one. Success appeared to be linked to a flexible approach alternating high and low intensity cuttings, group and individual selection.
The aim of this study was to identify the functional anatomic factors involved in the maintenance or disturbance of flow in the vertebral aa. during atlanto-axial rotation. Fourteen healthy ...volunteers were studied by magnetic resonance angiography (MRA) by a three-dimensional sequence in phase contrast centered on the vertebral aa. at the level of the cranio-cervical junction before and after left rotation of the head. A decrease in the signal intensity of the arterial flow was sought for. The results were compared to the posterolateral development of the loop of the vertebral a. in its atlanto-axial segment in neutral position, and to the measurement of the angular opening between the atlas and axis in dynamic position. Seven subjects also had a three-dimensional CT study (3D CT) of the bony relations of C1 and C2 after rotation. In 4 subjects a disturbance of flow in the right vertebral a. was observed in the transverse foramen of C2. This occurred when two factors were combined: an under-developed atlanto-axial arterial loop and a C1-C2 angle exceeding 35 degrees in maximal rotation. In the other subjects a well-developed arterial loop and/or a C1-C2 angle of less than 35 degrees in maximal rotation were factors preserving the arterial flow. The risk factor associated with the C1-C2 angle seemed correlated in 3D CT with loss of the usual asymmetric character of rotation. A clinical application is reported with a case combining chronic rotational dysfunction of the cranio-cervical junction as shown by 3D CT and complete compression of the vertebral a. in MRA, confirmed by conventional angiography. A knowledge of this physiopathologic mechanism allows clinical detection and evaluation of the risk of any effect of pathology of the cranio-cervical junction on the vertebral a.
A sarcolemma-rich fraction can be isolated after subcellular fractionation of mouse intercostal muscles by sedimentation on a discontinuous sucrose gradient. The quantitative recovery of the ...acetylcholine receptor in this fraction is about 50%, which indicates the presence of a high proportion of postsynaptic membranes. Acetylcholinesterase (AcChoEase; EC 3.1.1.7) is found mainly in three different layers: the top layer, which contains soluble AcChoEase, the intermediate layer (fraction A), and the last, AcChoR-rich, layer (fraction C). The relative proportions of the molecular forms of AcChoEase are different in the three layers. The ``16S'' AcChoEase is in a higher proportion in both types of membrane fractions (A and C) compared to soluble AcChoEase. Both total AcChoEase and 16S AcChoEase are enriched in the A and C fractions. In the C fraction, the sequential use of homogenizations in the presence of detergent and high ionic strength allows the ``solubilization'' of two distinct AcChoEase pools. One is detergent-soluble and mainly composed of slow-sedimenting forms; the other one is detergent-insoluble, high-ionic strength-soluble, and composed mainly of collagen-like, tailed, asymmetric (16S) AcChoEase. Thus, most of the asymmetric AcChoEase is specifically localized in the synaptic extracellular matrix of the mammalian muscle fiber. However, in the A fraction, most of the 16S AcChoEase found is solubilized by detergent alone, suggesting an association with microsomal membranes. It may mean that at least some of the basal lamina-embedded 16S AcChoEase is preassembled intracellularly in the sarcoplasmic reticulum.
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