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41.

Background

Spasticity is a common sequela of upper motor neuron pathology, such as cerebrovascular diseases and cerebral palsy. Intervention for spasticity of the ankle plantarflexors in physical therapy may include tone-inhibiting casting and/or orthoses for the ankle and foot. However, the physiological mechanism of tone reduction by such orthoses remains unclarified.

Objective

To investigate the electrophysiologic effects of tone-inhibiting insoles in stroke subjects with hemiparesis by measuring changes in reciprocal Ia inhibition (RI) in the ankle plantarflexor.

Design

An interventional before–after study.

Setting

Acute stroke unit or ambulatory rehabilitation clinic of a university hospital in Japan.

Participants

Ten subjects (47-84 years) with hemiparesis and 10 healthy male control subjects (31-59 years) were recruited.

Methods

RI of the spastic soleus in response to the electrical stimulation of the deep peroneal nerve was evaluated by stimulus-locked averaging of rectified electromyography (EMG) of the soleus while subjects were standing.

Main Outcome Measurements

The magnitude of RI, defined as the ratio of the lowest to the baseline amplitude of the rectified EMG at approximately 40 milliseconds after stimulation, was measured while subjects were standing with and without the tone-inhibiting insole on the hemiparesis side.

Results

Enhancement of EMG reduction with the tone-inhibiting insole was significant (P < .05) in the subjects with hemiparesis, whereas no significant changes were found in controls.

Conclusion

Tone-inhibiting insoles enhanced RI of the soleus in subjects after stroke, which might enhance standing stability by reducing unfavorable ankle plantarflexion tone.

Level of Evidence

III  相似文献   
42.
We compared vasti muscle electromyograms for two knee joint angles during fatiguing tetanic contractions. Tetanic contraction of the knee extensors was evoked for 70 s by electrical stimulation of the femoral nerve at knee joint angles of 60° (extended, with 0° indicating full extension) and 110° (flexed) in eight healthy men. Surface electromyography was recorded from the vastus intermedius (VI), vastus lateralis (VL) and vastus medialis (VM) muscles. Knee extension force and M‐wave amplitudes and durations were calculated every 7 s, which were normalized by the initial value. Normalized knee extension force was decreased at the flexed knee joint angle compared with that of the extended knee joint angle (P<0·05). Decreased normalized M‐wave amplitude and increased normalized M‐wave duration of the VI were greater at the flexed knee joint angle than the extended knee joint angle (P<0·05), whereas those for the VL and VM were similar (P>0·05). These results suggest that peripheral fatigue profiles of the VI might be greater at the flexed than the extended knee joint angles, but that of VL and VM might be similar in the tested range of knee joint angles (i.e. 60°–110°) during continuous tetanic contraction induced by electrical stimulation. Therefore, greater reduction of knee extension force at the flexed knee joint angle than the extended knee joint angle may reflect fatigue development of the VI more than other quadriceps femoris components.  相似文献   
43.

Purpose

Positron emission tomography (PET) in non-human primates (NHP) is commonly performed under anesthesia, with sevoflurane being a widely used inhaled anesthetic. PET measurement in NHP can be repeated, and a difference in radioligand kinetics has previously been observed between the first and second PET measurement on the same day using sevoflurane anesthesia. In this study, we evaluated the effect of prolonged sevoflurane anesthesia on kinetics and binding potential (BPND) of [11C]raclopride in NHP.

Procedures

Three cynomolgus monkeys underwent two to three PET measurements with [11C]raclopride under continuous sevoflurane anesthesia on the same day. The concentration of sevoflurane was adjusted according to the general conditions and safety parameters of the NHP. Time to peak (TTP) radioactivity in the striatum was estimated from time-activity curves (TACs). The BPND in the striatum was calculated by the simplified reference tissue model using the cerebellum as reference region.

Results

In each NHP, the TTP became shorter in the later PET measurements than in the first one. Across all measurements (n = 8), concentration of sevoflurane correlated with TTP (Spearman’s ρ = ? 0.79, p = 0.03), but not with BPND (ρ = ? 0.25, p = 0.55).

Conclusions

These data suggest that sevoflurane affects the shape of TACs but has no evident effect on BPND in consecutive PET measurements.
  相似文献   
44.
Tahata  Yuki  Hikita  Hayato  Mochida  Satoshi  Enomoto  Nobuyuki  Kawada  Norifumi  Kurosaki  Masayuki  Ido  Akio  Miki  Daiki  Yoshiji  Hitoshi  Takikawa  Yasuhiro  Sakamori  Ryotaro  Hiasa  Yoichi  Nakao  Kazuhiko  Kato  Naoya  Ueno  Yoshiyuki  Yatsuhashi  Hiroshi  Itoh  Yoshito  Tateishi  Ryosuke  Suda  Goki  Takami  Taro  Nakamoto  Yasunari  Asahina  Yasuhiro  Matsuura  Kentaro  Yamashita  Taro  Kanto  Tatsuya  Akuta  Norio  Terai  Shuji  Shimizu  Masahito  Sobue  Satoshi  Miyaki  Tomokatsu  Moriuchi  Akihiro  Yamada  Ryoko  Kodama  Takahiro  Tatsumi  Tomohide  Yamada  Tomomi  Takehara  Tetsuo 《Journal of gastroenterology》2022,57(2):120-132
Journal of Gastroenterology - Direct-acting antiviral (DAA) therapy enables a high rate of sustained virologic response (SVR) in patients with hepatitis C virus associated cirrhosis. However, the...  相似文献   
45.
Journal of Gastroenterology - Liquid biopsies, particularly those involving circulating tumor DNA (ctDNA), are rapidly emerging as a non-invasive alternative to tumor biopsies. However, clinical...  相似文献   
46.
Portal vein thrombosis is a rare surgical complication following liver transplantation, which remains a cause of graft loss and death. We describe here the treatment of portal vein thrombosis following living donor liver transplantation using an extended left lobe graft. The patient was treated with a Gore-Tex vascular jump graft extra-anatomically interposed between the recipient superior mesenteric vein and the donor umbilical vein. This technique allowed the hepatic hilum to be left untouched and supplied suitable blood flow to the hepatic allograft. Our experience suggests that this innovative technical solution can be helpful in the effort to rescue cases of hepatic allograft with vascular complications.  相似文献   
47.
Abstract

Purpose: To evaluate the effects of topical hyaluronan (HA) on corneal epithelial wound healing when administered with or without benzalkonium chloride (BAC).

Methods: A cultured human corneal epithelial cell line (HCE-T) was subjected to in vitro scratch assays and in situ epithelial migration was evaluated in organ-cultured rabbit corneas. The corneal epithelium of C57BL/6J mice was also evaluated to determine in vivo wound healing. An in vivo imaging system was also used to evaluate the effects of HA on eye drop retention on the ocular surface.

Results: The findings revealed the promotion of HCE-T migration, in situ rabbit corneal epithelial migration, and in vivo wound healing in mouse corneal epithelium by HA. Pre-treatment with HA also protected against delayed epithelial wound healing in BAC in vitro. However, pre-treatment with 3?mg/mL HA did not show a protective effect against BAC in vivo, but instead delayed epithelial wound healing and increased detection of cleaved caspase-3. This suggested that HA promotes the retention of BAC on the ocular surface. The instilled HA was retained after 15?min, at a significantly higher rate than for phosphate-buffered saline.

Conclusions: The combination of HA and BAC impaired wound healing in the corneal epithelium.  相似文献   
48.
[Purpose] The purpose of this study was to elucidate whether insoles alter postural sway on a sideward slope rather than on level ground. [Participants and Methods] This study involved 20 flat-footed individuals and 20 normal-footed individuals. The postural sway was determined based on the total length of the locus and the body sway area, which were measured using the Zebris system. The participants were divided into three groups: the BMZ insoles, Superfeet insoles, and no insole groups. These insoles were worn by the participants with their normal shoes worn daily. [Results] The total length of the locus of the BMZ group was significantly lower than those of the Superfeet and no-insole groups. The body sway area did not significantly differ based on the insole condition. [Conclusion] BMZ insoles improve postural sway in both normal-footed and flat-footed individuals on a sideward slope.  相似文献   
49.
The cell-cycle status of hematopoietic stem and progenitor cells (HSPCs) becomes activated following chemotherapy-induced stress, promoting bone marrow (BM) regeneration; however, the underlying molecular mechanism remains elusive. Here we show that BM-resident group 2 innate lymphoid cells (ILC2s) support the recovery of HSPCs from 5-fluorouracil (5-FU)–induced stress by secreting granulocyte-macrophage colony-stimulating factor (GM-CSF). Mechanistically, IL-33 released from chemo-sensitive B cell progenitors activates MyD88-mediated secretion of GM-CSF in ILC2, suggesting the existence of a B cell–ILC2 axis for maintaining hematopoietic homeostasis. GM-CSF knockout mice treated with 5-FU showed severe loss of myeloid lineage cells, causing lethality, which was rescued by transferring BM ILC2s from wild-type mice. Further, the adoptive transfer of ILC2s to 5-FU–treated mice accelerates hematopoietic recovery, while the reduction of ILC2s results in the opposite effect. Thus, ILC2s may function by “sensing” the damaged BM spaces and subsequently support hematopoietic recovery under stress conditions.  相似文献   
50.
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