Both arthroscopic one-step Broström-Gould and Lasso-loop stitch techniques achieved favourable clinical outcomes for chronic lateral ankle instability

PURPOSE

Both the arthroscopic Broström-Gould and Lasso-loop stitch techniques are commonly used to treat chronic lateral ankle instability (CLAI). The purpose of this study is to introduce an arthroscopic one-step outside-in Broström-Gould (AOBG) technique and compare the mid-term outcomes of the AOBG technique and Lasso-loop stitch technique.

METHODS

All CLAI patients who underwent arthroscopic lateral ankle stabilization surgery in our department from 2018 to 2019 were retrospectively enrolled. The patients were divided into two groups according to the surgical methods employed: the AOBG technique (Group A) and the Lasso-loop technique (Group B). The visual analogue scale pain score, American Orthopaedic Foot and Ankle Society ankle hindfoot score, Tegner activity score and Karlsson-Peterson score were evaluated preoperatively and during the follow-up from June to December 2022. The surgical duration, return to sports, sprain recurrence and surgical complications were also recorded and compared.

RESULTS

A total of 74 patients (Group A, n = 42; Group B, n = 32) were included in this study with a mean follow-up of 39 months. No statistically significant differences were observed in demographic parameters or follow-up time between the two groups. Postoperative clinical scores indicated a significant improvement (all with p < 0.001) with no significant difference between the two groups (not significant [n.s.]). There was no significant difference in the surgical duration (46.1 vs. 49.7 min, n.s.), return to sports (92.9% vs. 93.8%, n.s.), or sprain recurrence (4.8% vs. 6.3%, n.s.). Only two cases in Group A reported knot irritation (4.8% vs. 0, n.s.), and one case in Group A experienced local skin numbness (0 vs. 3.1%, n.s.), with no significant difference.

CONCLUSION

Both the AOBG and Lasso-loop stitch techniques yielded comparable favourable mid-term outcomes and return to sports with a low rate of surgical complications. Both procedures could be feasible strategies for CLAI patients.

LEVEL OF EVIDENCE

Level III.

Endocytosis-mediated entry of a caterpillar effector into plants is countered by Jasmonate

Insects and pathogens release effectors into plant cells to weaken the host defense or immune response. While the imports of some bacterial and fungal effectors into plants have been previously characterized, the mechanisms of how caterpillar effectors enter plant cells remain a mystery. Using live cell imaging and real-time protein tracking, we show that HARP1, an effector from the oral secretions of cotton bollworm (Helicoverpa armigera), enters plant cells via protein-mediated endocytosis. The entry of HARP1 into a plant cell depends on its interaction with vesicle trafficking components including CTL1, PATL2, and TET8. The plant defense hormone jasmonate (JA) restricts HARP1 import by inhibiting endocytosis and HARP1 loading into endosomes. Combined with the previous report that HARP1 inhibits JA signaling output in host plants, it unveils that the effector and JA establish a defense and counter-defense loop reflecting the robust arms race between plants and insects.

Dirigent gene editing of gossypol enantiomers for toxicity-depleted cotton seeds

Axial chirality of biaryls can generate varied bioactivities. Gossypol is a binaphthyl compound made by cotton plants. Of its two axially chiral isomers, (-)-gossypol is the bioactive form in mammals and has antispermatogenic activity, and its accumulation in cotton seeds poses health concerns. Here we identified two extracellular dirigent proteins (DIRs) from Gossypium hirsutum, GhDIR5 and GhDIR6, which impart the hemigossypol oxidative coupling into (-)- and (+)-gossypol, respectively. To reduce cotton seed toxicity, we disrupted GhDIR5 by genome editing, which eliminated (-)-gossypol but had no effects on other phytoalexins, including (+)-gossypol, that provide pest resistance. Reciprocal mutagenesis identified three residues responsible for enantioselectivity. The (-)-gossypol-forming DIRs emerged later than their enantiocomplementary counterparts, from tandem gene duplications that occurred shortly after the cotton genus diverged. Our study offers insight into how plants control enantiomeric ratios and how to selectively modify the chemical spectra of cotton plants and thereby improve crop quality.

Sphingolipid metabolism, transport, and functions in plants: Recent progress and future perspectives

Sphingolipids, which comprise membrane systems together with other lipids, are ubiquitous in cellular organisms. They show a high degree of diversity across plant species and vary in their structures, properties, and functions. Benefiting from the development of lipidomic techniques, over 300 plant sphingolipids have been identified. Generally divided into free long-chain bases (LCBs), ceramides, glycosylceramides (GlcCers) and glycosyl inositol phosphoceramides (GIPCs), plant sphingolipids exhibit organized aggregation within lipid membranes to form raft domains with sterols. Accumulating evidence has revealed that sphingolipids obey certain trafficking and distribution rules and confer unique properties to membranes. Functional studies using sphingolipid biosynthetic mutants demonstrate that sphingolipids participate in plant developmental regulation, stimulus sensing, and stress responses. Here, we present an updated metabolism/degradation map and summarize the structures of plant sphingolipids, review recent progress in understanding the functions of sphingolipids in plant development and stress responses, and review sphingolipid distribution and trafficking in plant cells. We also highlight some important challenges and issues that we may face during the process of studying sphingolipids.

Arabidopsis leaf extracellular vesicles in wound-induced jasmonate accumulation

The plant extracellular vesicles (EVs) are lipid-enveloped nano-particles containing proteins, nucleic acids and metabolites and function in plant development and response. The Arabidopsis four transmembrane protein TETRASPANIN 8 (TET8) knock-out mutant tet8 secreted less EVs than the wild-type (WT). In this report, we show that the tet8 mutant was attenuated in the plant hormone jasmonate (JA) accumulation in response to mechanical wounding treatment. We also noticed that the EVs contained a high level of phospholipids phosphatidic acids (PAs) which may serve as precursors of JA biosynthesis during wound-triggered-self-healing processes. Thus, we propose an open question about a potential role of EVs or TET8 or both in damage-associated JA response.

Lipidomic Analysis Reveals the Importance of GIPCs in Arabidopsis Leaf Extracellular Vesicles

Plant extracellular vesicles (EVs) are membrane-enclosed nanoparticles that play diverse roles in plant development and response. Recently, impressive progress has been made in the isolation and identification of the proteins and RNAs carried in plant EVs; however, the analysis of EV lipid compositions remains rudimentary. Here, we performed lipidomic analysis of Arabidopsis rosette leaf EVs, revealing a high abundance of certain groups of lipids, in particular sphingolipids, in the EVs. Remarkably, the EV sphingolipids are composed of nearly pure glycosylinositolphosphoceramides (GIPCs), which are green lineage abundant and negatively charged. We further showed that the Arabidopsis TETRASPANIN 8 (TET8) knockout mutant has a lower amount of cellular GIPCs and secrets fewer EVs, companied with impaired reactive oxygen species (ROS) burst toward stresses. Exogenous application of GIPCs promoted the secretion of EVs and ROS burst in both the WT and tet8 mutant. The characteristic enrichment of sphingolipid GIPCs provides valuable insights into the biogenesis and function of plant EVs.

Phytosphinganine Affects Plasmodesmata Permeability via Facilitating PDLP5-Stimulated Callose Accumulation in Arabidopsis

Plant plasmodesmata (PDs) are specialized channels that enable communication between neighboring cells. The intercellular permeability of PDs, which affects plant development, defense, and responses to stimuli, must be tightly regulated. However, the lipid compositions of PD membrane and their impact on PD permeability remain elusive. Here, we report that the Arabidopsis sld1 sld2 double mutant, lacking sphingolipid long-chain base 8 desaturases 1 and 2, displayed decreased PD permeability due to a significant increase in callose accumulation. PD-located protein 5 (PDLP5) was significantly enriched in the leaf epidermal cells of sld1 sld2 and showed specific binding affinity to phytosphinganine (t18:0), suggesting that the enrichment of t18:0-based sphingolipids in sld1 sld2 PDs might facilitate the recruitment of PDLP5 proteins to PDs. The sld1 sld2 double mutant seedlings showed enhanced resistance to the fungal-wilt pathogen Verticillium dahlia and the bacterium Pseudomonas syringae pv. tomato DC3000, which could be fully rescued in sld1 sld2 pdlp5 triple mutant. Taken together, these results indicate that phytosphinganine might regulate PD functions and cell-to-cell communication by modifying the level of PDLP5 in PD membranes.

Targeted Lipidomics Studies Reveal that Linolenic Acid Promotes Cotton Fiber Elongation by Activating Phosphatidylinositol and Phosphatidylinositol Monophosphate Biosynthesis

The membrane lipids from fast-elongating wild-type cotton (Gossypium hirsutum) fibers at 10 days post-anthesis, wild-type ovules with fiber cells removed, and ovules from the fuzzless-lintless mutant harvested at the same age, were extracted, separated, and quantified. Fiber cells contained significantly higher amounts of phosphatidylinositol (PI) than both ovule samples with PI 34:3 being the most predominant species. The genes encoding fatty acid desaturases (Δ(15)GhFAD), PI synthase (PIS) and PI kinase (PIK) were expressed in a fiber-preferential manner. Further analysis of phosphatidylinositol monophosphate (PIP) indicated that elongating fibers contained four- to five-fold higher amounts of PIP 34:3 than the ovules. Exogenously applied linolenic acid (C18:3), soybean L-α-PI, and PIPs containing PIP 34:3 promoted significant fiber growth, whereas a liver PI lacking the C18:3 moiety, linoleic acid, and PIP 36:2 were completely ineffective. The growth inhibitory effects of carbenoxolone, 5-hydroxytryptamine, and wortmannin were reverted by C18:3, PI, or PIP, respectively, suggesting that PIP signaling is essential for fiber cell growth. Furthermore, cotton plants expressing virus-induced gene-silencing constructs that specifically suppressed GhΔ(15)FAD, GhPIS, or GhPIK expression, resulted in significantly short-fibered phenotypes. Our data provide the basis for in-depth studies on the roles of PI and PIP in mediating cotton fiber growth.

The maternal spinal cord: biochemical and physiological correlates of steroid-activated antinociceptive processes

Physiological gestation, as well as the simulation of the associated changes in estrogen and progesterone, is associated with significant elevations in nociceptive response thresholds. This is mediated by spinal cord kappa- and delta-opIoid systems. The predominant spinal mu-opioid system does not appear to participate. One hallmark of pregnancy- and hormonally-induced antinociception is the multiplicative interaction among its components. Approximately 40% results from spinal kappa/delta analgesic synergy on which is superimposed an additional increment (approximately 60%) of synergy that results from the interaction between descending spinal alpha 2-noradrenergic and spinal kappa/delta activities. An intact hypogastric nerve is required for the spinal alpha 2-noradrenergic component. This would explain the requirement for an intact hypogastric nerve in order for the antinociception of pregnancy and its hormonal simulation to be fully manifest. The predominant means by which spinal dynorphin-containing neurons adjust to increased demand is increased post-translational processing of dynorphin precursor intermediates which are present at approximately 10x the concentration of mature dynorphin peptides (1-17 and 1-8). This is indicated by the concomitant decline (approximately 50%) in the spinal cord content of dynorphin precursors and increase (approximately 87%) in the content of prohormone convertase 2, a processing enzyme sufficient to generate mature dynorphin peptides from prodynorphin. The presence of 'high gain' multiplicative spinal opioid antinociceptive pathways that can be activated by estrogen and progesterone has hyperalgesic implications as well, i.e. it could result in disproportionately increased pain responsiveness. This might explain, in part, findings that women are more prone to recurrent pain and pain of greater duration and intensity than men. The underlying mechanisms of gestational antinociception could point the way to pain pharmacotherapies that are gender-based.

[Site-directed mutagenesis at disulfide bond Cys206-Cys210 of prochymosin (chymosin)]

During the work of site-directed mutagenesis at disulfide bond Cys206-Cys210 of prochymosin, it was found that the corresponding template sequence had the potential to form a loop-stem structure with free energy of -16.1 kcal/mol, which prevent the template from pairing with primer and, in turn, the synthesis of the mutated DNA strand. Rapid annealing can overcome this difficulty. Five expression plasmids of prochymosin muants with deletion of Cys206-Cys210 (C206A, C210A, C206A/C210A, C210S and C206S/C210S) were constructed. Except for C206A they were expressed at high level in E. coli amounting to 50% of the total cellular proteins. Renaturation of the mutant prochymosin indicated that Cys206-Cys210 is dispensable for correct refolding of prochymosin. However, the amino acid residues at Cys206 and/or Cys 210 play a critical role in determining the renaturation. Among the five mutants the reactivation efficiency of C206A/C210A were about 4.5-fold, 20-fold and 30-fold higher than that of C206S/C210S, C210A and C210S respectively. C206A can not correctly refold at all. CD spectra in the far UV region indicate that C206A/C210A and C206S/C210S chymosin analogs have a secondary structure almost identical to that of the wild-type chymosin. Fluorescence spectroscopic analysis revealed that mutant chymosins have the same emission maximum at 333 nm as the wild-type chymosin but their fluorescence intensities at 333 nm are much higher than that of the wild-type chymosin. Considering that the mutants and the wild-type chymosin exhibit almost the same specific activity, it is reasonable to conclude that the mutant proteins assume a native active information with a perturbance around some tryptophan residues.

Inflammatory pseudotumor of the liver mimicking a malignancy: case report

Inflammatory pseudotumor (IPT) is a rare lesion of the liver that can be clinically indistinguishable from a malignant tumor. A 51-year-old woman was hospitalized for upper abdominal pain and a weight loss of 5 Kg in 2 months. Radiological examination showed a large heterogenous hypervascular mass in the left lobe of her liver, strongly in favor of hepatocellular carcinoma. However, an ultrasound-guided liver biopsy revealed the typical characteristics of IPT, which consist of plump spindle cells with dense inflammatory cell infiltration. A left lobectomy was performed. No microorganisms were found on stained sections. The markedly elevated eosinophil count reverted to normal postoperatively and she remained well on follow-up examination 8 months after discharge. This case exemplifies the difficulty in radiological diagnosis of hepatic IPT and underscores the importance of its histological differentiation from malignancy before laparotomy.

Prolonged ovarian sex steroid treatment of male rats produces antinociception: identification of sex-based divergent analgesic mechanisms

Simulation of the pregnancy blood concentration profile of 17beta-estradiol (E(2)) and progesterone (P) in nonpregnant ovariectomized rats has been shown to result in a significant elevation of nociceptive response thresholds. The present report demonstrates that spinal opioid antinociceptive responsiveness to these ovarian steroids is not sex-specific. Treatment of orchidectomized sexually mature males with an analogous regimen of E(2) and P also elicits an antinociception, the robustness and temporal profile of which is comparable with that previously observed in females. Neither E(2) nor P, alone, is sufficient to produce antinociception in male rats, as was previously demonstrated in females. Neurobiological substrates and antinociceptive mechanisms underlying ovarian sex steroid antinociception do, however, exhibit sex specificity. In males, the analgesia resulting from ovarian steroid treatment derives from the independent contributions of spinal kappa and mu, not delta, opioid receptor pathways that are additive, not synergistic. Spinal alpha(2)-noradrenergic receptor activity and its attendant analgesic synergy with spinal opioid systems do not contribute to ovarian sex steroid analgesia in males. This is in contrast to the previous demonstrations that ovarian sex steroid-induced antinociception in females results from antinociceptive synergy between activated spinal kappa/delta opioid as well as alpha(2)-noradrenergic receptor systems. The current data reveal that ovarian steroid-activated multiplicative spinal antinociceptive pathways that had been demonstrated in female rats are not manifest in their male counterparts.

Gestational and ovarian sex steroid antinociception: relevance of uterine afferent and spinal alpha(2)-noradrenergic activity

Pregnancy is associated with an antinociception that is multifactorial and results from spinal (kappa/delta) opioid antinociceptive pathways as well as peripheral processes (ovarian sex steroids, uterine afferent neurotransmission). The present results provide the first indication that the full manifestation of pregnancy-induced analgesia also requires a supraspinal component. The analgesia of gestation or its hormonal simulation (via estrogen and progesterone administration; HSP) is substantially attenuated (>/=60%) following blockade of spinal alpha(2) (but not alpha(1)) adrenergic receptors. HSP antinociception is also attenuated by transection of the hypogastric nerve, the magnitude of which is indistinguishable from that produced by spinal alpha(2) receptor blockade. Additionally, hypogastric neurectomy abolishes the component of the antinociception associated with HSP that is mediated by spinal alpha(2) receptors. This suggests that the augmented spinal noradrenergic activity during HSP is not due to activation at the terminal of noradrenergic spinal projection neurons but requires supraspinal activity. It is suggested that enhanced spinal noradrenergic activity amplifies ongoing spinal kappa/delta antinociception as has been observed following the concomitant intrathecal application of alpha(2) and opioid agonists. The current observations underscore the importance of visceral afferent activity as well as its modulation by a female-specific hormonal milieu to the efficacy of endogenous spinal opioid antinociception.

Primary hepatic epithelioid hemangioendothelioma: case report

Hepatic epithelioid hemangioendothelioma (HEH) is a very rare vascular tumor of the liver. It usually affects adult women and presents as multiple hepatic nodules with mainly peripheral distribution. It poses special difficulties for clinicians in its diagnosis and treatment because of its non-specific clinical manifestations and findings on imaging, and it is easy to be misdiagnosed pathologically. Its clinical course and prognosis are variable but supposed to be intermediate between hemangioma and angiosarcoma. The primary treatments of choice are radical resection or liver transplantation. We report a 62-year-old man with right upper quadrant abdominal pain of several days' duration, who was initially misdiagnosed as having a liver abscess. Finally, HEH was diagnosed on the basis of positive immunohistochemical staining for factor VIII-related antigen in tumor cells. This case could serve to highlight the pitfalls in diagnosing this rare tumor. Increasing the index of suspicion and familiarity with the radiological and histological characteristics of this tumor would facilitate the accurate diagnosis and thus avoid unnecessary interventions.

Inductive regulation of cell fusion in leech

Cell-cell fusion is a component of many different developmental processes, but little is known about how cell-cell fusion is regulated. Here we investigate the regulation of a stereotyped cell-cell fusion event that occurs among the endodermal precursor cells of the glossiphoniid leech Helobdella robusta. We find that this fusion event is regulated inductively by a cell that does not itself fuse. We also show that biochemical arrest (by microinjection with ricin A chain or ribonuclease A) of the inducer or either of the fusion partners prevents fusion, but only if the arrest is initiated during a critical period long before the time at which fusion normally occurs. If the arrest occurs after this critical period, fusion occurs on schedule. These results suggest that both fusion partners play active roles in the process and that neither the induction nor the fusion itself requires concomitant protein synthesis.

Pediatric ethmoid mucoceles in cystic fibrosis: long-term follow-up of reported cases

Ethmoid mucocele, a condition that usually affects adults, can be found in both children and infants with cystic fibrosis. We have cared for two patients with cystic fibrosis and ethmoid mucoceles. Because we could find no references to the prognosis or any long-term follow-up data for this disorder, we contacted the physicians and families of six of the seven patients with this condition previously reported in the English literature to determine how they were managed surgically and the incidence of recurrence. Regardless of the mode of therapy, none of the mucoceles recurred.

Cholecystokinin octapeptide reverses the inhibitory effect induced by electroacupuncture on C-fiber evoked discharges

Extracellular single unit recordings were made from spinal dorsal horn wide dynamic range neurons in spinal transected, urethane-anesthetized rats. The unit discharges elicited by noxious electrical stimulation of the hind paw were suppressed by electroacupuncture (15 Hz, 0.3 ms, 3 mA, 30 min) placed at the hind leg points (S-36 and SP-6). Local spinal superfusion with naloxone (20 micrograms/15 microliters) or CCK-8 (10 ng/15 microliters) attenuated, whereas CCK-B receptor antagonist L365,260 (2.5 micrograms/15 microliters) enhanced the electroacupuncture effect. These findings provide further evidence for the notion that CCK-8, in the spinal cord, functions as an antiopioid substrate that antagonizes opioid- or electroacupuncture-induced analgesia.

Cholecystokinin octapeptide reverses the kappa-opioid-receptor-mediated depression of calcium current in rat dorsal root ganglion neurons

Although the cholecystokinin octapeptide (CCK-8) is reported to antagonize the kappa-opioid-receptor-mediated analgesic effect in spinal cord, its mechanism and sites of action remain obscure. In the present study, the whole-cell patch-clamp recording technique was employed to examine the effect of kappa-opioid agonist U50488H on voltage-gated calcium channels and the interaction between the CCK-8 and U50488H in acutely isolated rat dorsal root ganglion neurons. The results indicate that the calcium currents elicited in dorsal root ganglion neurons can be depressed by U50488H, an effect readily reversed by the kappa-opioid receptor antagonist Nor-BNI or by the antiopioid peptide CCK-8. The effect of the CCK-8 can be abolished by the CCK-B receptor antagonist, L365,260. While CCK-8 showed a potent opioid-reversal effect, it by itself exerted a slight inhibitory effect on calcium current. This novel observation in the dorsal root ganglion neurons indicates that CCK-8 can antagonize the kappa-opioid-receptor-mediated depressant effect on voltage-gated calcium current, and this antagonizing effect appears to be mediated via CCK-B receptor.

[Current status of the application of patch-clamp technique and its combinations with other techniques]

The Patch-clamp technique, as an advanced electrophysiological technique, has been widely used for research in the life science research field. A recent trend is to combine this technique with other techniques, such as the Fura-2 microfluorimetry for measuring the concentration of Ca2+, electrochemical detection with carbon-fiber electrode (i.e. amperometric detection or amperometry), and single-cell reverse transcription of RNA followed by the polymerase chain reaction (RT-PCR). This article is to summarize the current status of the use of patch-clamp technique and its combinations with other techniques in solving problems related with transmembrane signal transduction in neurobiology.

Cholecystokinin octapeptide reverses mu-opioid-receptor-mediated inhibition of calcium current in rat dorsal root ganglion neurons

Cholecystokinin octapeptide (CCK-8) is reported to antagonize the analgesic effect produced by mu- and kappa- but not delta-opioid agonist in spinal cord. However, the mechanisms of interaction remain obscure. In the present study, whole-cell patch-clamp recording was performed on acutely isolated rat dorsal root ganglion (DRG) neurons to evaluate the effects of the highly specific mu-opioid agonist ohmefentanyl and the delta-opioid agonist DPDPE on voltage-gated calcium channels and the possible interaction between CCK-8 receptor and mu- or delta-opioid receptor. The results indicated that ohmefentanyl, but not DPDPE, can suppress the voltage-gated calcium currents elicited in DRG neurons, an effect readily reversed by naloxone or by the antiopioid peptide CCK-8. The effect of CCK-8 can in turn be abolished by the CCK-B receptor antagonist L365,260. CCK-8 used by itself has no enhancing effect, but rather a depressant effect, on calcium currents. However, used simultaneously with ohmefentanyl, CCK-8 shows a clear-cut reversal of depression of the mu-opioid. We conclude that the depressant effect produced by mu-opioid on voltage-gated calcium current in DRG neurons can be antagonized by CCK-8 through CCK-B receptor located in the same neuron. The delta-opioid DPDPE has no direct effect on the voltage-gated calcium current in DRG neurons.

Granulomatous hepatitis associated with scrub typhus

A 56 year old patient with scrub typhus infection having unusual presentation of hepatic injury resembling acute hepatitis is described. The clinical features of fever, headache, eschar, lymphadenopathy, lymphocytosis and high Rickettsia tsutsugamushi immunofluorescence titres confirmed the diagnosis of scrub typhus. Acute hepatitis was proven by hepatic biochemical tests and liver biopsy. The patient had a complete recovery soon after antibiotic treatment. The presentation of this case suggests that scrub typhus infection should be included in the list of differential diagnosis of acute hepatitis or granulomatous hepatitis, at least in the Asian Pacific region where scrub typhus still prevails.