There is increasing evidence that the architectural design and arrangement of the fibers within a motor unit have important physiological and developmental ramifications. Limited data, however, are available to directly address this issue. In the present study the physiological properties of one motor unit in each of seven cat tibialis anterior (TA) muscles were determined. Each of these units then was repetitively stimulated to deplete the glycogen in all muscle fibers within the unit. Subsequently, the length, type of ending, and spatial distribution of fibers sampled from these physiologically and histochemically typed motor units were determined. Four fast fatigable (FF), one fast, fatigue resistant (FR), and two slow (S) motor units (MU) were studied. The samples consisted of all those glycogen-depleted fibers (9-27) contained within a single fascicle or a circumscribed area of each of the motor unit territories. The mean fiber lengths for the two slow motor units were 35.9 and 45.5 mm. The mean fiber lengths for the fast motor unit samples ranged from 8.8 to 48.5 mm. Some fibers of both the fast and slow units reached lengths of 58 mm. Most of the fibers in the slow units extended the entire distance between the proximal and distal musculotendinous planes, had relatively constant cross-sectional areas, and terminated at the tendon as blunt endings. In contrast, the majority of the fibers in the fast units terminated intrafascicularly at one end, and the cross-sectional area decreased progressively along their lengths, that is, showed a tapering pattern for a significant proportion of their lengths. Therefore, the force generated by units that end midfascicularly would appear to be transmitted to connective tissue elements and/or adjacent fibers. All fibers of a fast unit within a fascicle were located at approximately the same proximo-distal location. Thus, developmentally the selection of muscle fibers by a motoneuron would seem to be influenced by their spatial distribution. The architectural complexities of motor units also have clear implications for the mechanical interactions of active and inactive motor units. For example, the tension capabilities of a motor unit may be influenced not only by the spatial arrangement of its own fibers, but also by the level of activation of neighboring motor units.
Background Polycystic ovary syndrome (PCOS) is a common reproductive and metabolic disorder in women; however, many clinicians may not be well versed in scientific advances that aid understanding of the associated reproductive, metabolic, and psychological abnormalities. Women with PCOS are dissatisfied with health care providers, the diagnostic process, and the initial treatment of PCOS and seek information through alternative sources. This has affected the patient-physician relationship by allowing medical information acquired through the internet, whether correct or not, to become accessible to patients and reshape their health care perspective. Patient dissatisfaction with health care providers regarding PCOS raises questions about the responsibilities of academic institutions to adequately train and maintain the competence of clinicians and government agencies to sufficiently support scientific investigation in this field. Objective The primary aim was to examine internet searching behaviors of the public regarding PCOS vs another highly prevalent gynecologic disorder. The secondary aim was to explore satisfaction with health care among patients with PCOS and their internet use. The tertiary aim was to examine medical education in reproductive endocrinology and infertility (REI) during obstetrics and gynecology (Ob/Gyn) residency as a proxy for physician knowledge in this field. Methods Google search trends and StoryBase quantified monthly Google absolute search volumes for search terms related to PCOS and fibroids (January 2004 to December 2017; United States). The reproductive disorder, fibroids, was selected as a comparison group because of its high prevalence among women. Between female groups, monthly absolute search volumes and their trends were compared. A Web-based questionnaire (June 2015 to March 2018) explored health care experiences and the internet use of women with PCOS. REI rotation information during Ob/Gyn residency in the United States was obtained from the Association of Professors of Gynecology and Obstetrics website. Results For PCOS (R=0.89; P<.01), but not fibroids (R=0.09; P=.25), monthly absolute search volumes increased significantly. PCOS-related monthly absolute search volumes (mean 384,423 searches, SD 88,756) were significantly greater than fibroid-related monthly absolute search volumes (mean 348,502 searches, SD 37,317; P<.05). PCOS was diagnosed by an Ob/Gyn in 60.9% (462/759) of patients, and 57.3% (435/759) of patients were dissatisfied with overall care. Among patients with PCOS, 98.2% (716/729) searched for PCOS on the Web but only 18.8% (143/729) of patients joined an online PCOS support group or forum. On average, Ob/Gyn residencies dedicated only 4% (2/43) of total block time to REI, whereas 5.5% (11/200) of such residencies did not offer any REI rotations. Conclusions Over time, PCOS has been increasingly searched on the Web compared with another highly prevalent gynecologic disorder. Patients with PCOS are dissatisfied with their health care providers, who would benefit from an improved understanding of PCOS during Ob/Gyn residency training.
Chronic endometritis is characterized by plasma cell (PC) infiltration of endometrial stroma. Identification of PCs can be challenging by routine hematoxylin and eosin (H&E) stain due to the low numbers of PCs or to their being obscured by other cells in the stroma. CD138 is widely used as an ancillary immunohistochemistry stain to identify PCs; however, it has a high background reaction. In this study, multiple myeloma 1 (MUM1) transcription factor is introduced as an alternative PC marker in endometrial tissues. In this study, 311 endometrial biopsies, submitted to rule out chronic endometritis, were selected. They were divided into Group I (n = 87) and Group II (n = 224). Both had MUM1 and H&E while Group I also had accompanying CD138 stains. In both groups combined, MUM1 detected plasma cells in 48% of the cases, while CD138 and H&E identified the cells in 23% and 15% of the biopsies, respectively. In addition to having a clean background, MUM1 is a more sensitive stain than CD138 for detection of PCs in endometrium.
Background: Isolated brain metastasis (IBM) from cervical cancer is a very rare encounter in neurosurgery. We sought to understand how patients with isolated brain metastases differ from those with metastases in the setting of widespread disease. Methods: A systematic review was completed using PubMed and the Cochrane Library. Patients with isolated brain metastases (IBM) and non-isolated brain metastases (NIBM, or brain metastases in the setting of disseminated disease), were compared. Two-sided statistical tests were used to determine significance. Survival function was carried out using the Kaplan–Meier method. Results: A total of 89 patients, 25 with IBM and 64 with NIBM, were identified. The time interval between initial diagnosis of cervical cancer and diagnosis of brain lesion was significantly shorter in the IBM group (median 7.5 vs. 20.05 months, and IBM vs. NIBM, respectively; P = 0.006). Overall survival from initial diagnosis of cervical cancer was significantly shorter for the IBM group versus the NIBM group (7.63 vs. 26.3 months, respectively; P = 0.0005). Data demonstrate a 3.4-fold reduction of median life expectancy to 7.63 months. Survival after diagnosis of brain metastases did not differ between groups (median, IBM 7 months vs. NIBM 4 months, P = 0.08). Conclusion: Taken together, our data suggest that for cervical cancer patients with brain metastasis intracranial metastasis itself (and not overall tumor burden) represent a sentinel event in limiting longevity. While the present study is underpowered to compare treatment options directly, further work should be focused on determining the optimal treatment for these patients.
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