Generation of zwitterionic trifluoromethyl N-allylic ylides and their use in switchable divergent annulations.

The previously unreported zwitterionic N-allylic ylide species from the corresponding Morita-Baylis-Hillman carbonates of trifluoromethyl ketones and acrylonitrile are generated under the catalysis of cinchona-derived tertiary amines, and subsequently participate in switchable asymmetric [3+2] or [4+1] annulations with 1-azadienes in chemo-, regio-, and stereodivergent manners via catalyst or substrate control. A diverse range of frameworks, having a trifluoromethylated all-carbon quaternary stereogenic centre or a tetrasubstituted alkene moiety, are generally constructed in good yields with excellent enantioselectivity.

The effect of platelet-rich plasma on the fusion rate and clinical outcome of spinal fusion surgery: A systematic review and meta-analysis.

BACKGROUND: Platelet-rich plasma (PRP) is widely used in many orthopedic surgeries and spinal disease treatments; however, the effect of PRP on spinal fusion remains controversial. QUESTIONS/PURPOSES: To assess the fusion rate and clinical results of PRP compared with non-PRP administration in the treatment of spinal fusion with regard to decreasing pain and improving healing and function. PATIENTS AND METHODS: Studies comparing PRP to non-PRP treatment with respect to the fusion rate and clinical outcome in patients who underwent spinal fusion surgery were included. RESULT: Three randomized controlled trials (RCTs) and 7 prospective cohort studies were identified. The spinal fusion rate was not significantly different between the groups in all RCTs or cohort studies at the final follow-up. In comparison, PRP significantly reduced pain after surgery as evaluated in the RCT analysis and the complication rate did not differ significantly between the two groups. CONCLUSION: According to the available studies, PRP does not contribute to the union rate, relieve pain or increase the complication rate in spinal fusion surgery. As clinical heterogeneity exists in these studies, further large, well-designed RCTs that focus on the standard assessment of PRP are needed.

Sacroiliac joint fusion VS conservative management for chronic low back pain attributed to the sacroiliac joint: A protocol for systematic review and meta analysis.

INTRODUCTION: Low back pain (LBP) is high prevalent and it is the leading cause of years lived with disability in both developed and developing countries. The sacroiliac joint (SIJ) is a common reason that caused LBP. At present, the treatment of chronic LBP attributed to SIJ is mainly conservative treatment and surgical treatment. However, there are still controversies between the 2 treating methods, and there is no recognized standard of treatment or surgical indications. Recent publications indicated that minimally invasive sacroiliac joint arthrodesis was safe and more effective improving pain, disability, and quality of life compared with conservative management in 2 years follow-up, which re-raise the focus of sacroiliac joints fusion. This paper will systematically review the available evidence, comparing the effectiveness of sacroiliac joint fusion and conservative therapy for the treatment of gait retraining for patients suffered from LBP attributed to the sacroiliac joint. METHOD AND ANALYSIS: A systematic review and meta-analysis of relevant studies in Pubmed, Embase, SCOPUS, and Cochrane Library will be synthesized. Inclusion criteria will be studies evaluating clinical outcomes (i.e., changes to pain and/or function) comparing sacroiliac joint fusion and conservative therapy in populations sacroiliac join related LBP; studies with less than 10 participants in total will be excluded. The primary outcomes measured will be pain score, Oswestry Disability Index (ODI), and adverse events during treatment. Review Manager (Revman; Version 5.3) software will be used for data synthesis, sensitivity analysis, meta-regression, subgroup analysis, and risk of bias assessment. A funnel plot will be developed to evaluate reporting bias and Begg and Egger tests will be used to assess funnel plot symmetries. We will use the Grading of Recommendations Assessment, Development and Evaluation system to assess the quality of evidence. ETHICS AND DISSEMINATION: Our aim is to publish this systematic review and meta-analysis in a peer-reviewed journal. Our findings will provide information comparing the efficacy and safety comparing sacroiliac joint fusion and non-surgical treatment for patients with LBP attributed to the sacroiliac joint. This review will not require ethical approval as there are no issues about participant privacy.

Asymmetric (4 + 3) and (4 + 1) Annulations of Isatin-derived Morita-Baylis-Hillman Carbonates to Construct Diverse Chiral Heterocyclic Frameworks.

A chiral tertiary amine-catalyzed asymmetric γ-regioselective (4 + 3) annulation reaction of isatin-derived Morita-Baylis-Hillman carbonates and 1-azadienes was developed, delivering chiral azepane spirooxindoles with excellent stereoselectivity. In addition, by tuning the substituents of Morita-Baylis-Hillman carbonates, the switchable γ-(4 + 3) or α-(4 + 1) annulation reaction with o-quinone methides was observed to furnish benzo[b]oxepines or 2,3-dihydrobenzofurans, respectively, under similar catalytic conditions.

MiR-449a suppresses the epithelial-mesenchymal transition and metastasis of hepatocellular carcinoma by multiple targets.

BACKGROUND: Increasing evidence indicates that Epithelial-mesenchymal transition (EMT) can be regulated by microRNAs (miRNAs). MiR-449a is a liver abundant miRNA. However, the role of miR-449a in the metastasis of hepatocellular carcinoma (HCC) remains largely unknown. METHODS: The expression levels of miR-449a were first examined in HCC cell lines and tumour tissues by real-time PCR. The in vitro and in vivo functional effect and underlying molecular mechanisms of miR-449a were examined further. RESULTS: In the present study, we found that miR-449a was significantly decreased in HCC cells and tissues, especially in those with the portal vein tumor thrombus. In HCC cell lines, stable overexpression of miR-449a was sufficient to inhibit cell motility in vitro, and pulmonary metastasis in vivo. In addition, ectopic overexpression of miR-449a in HCC cells promoted the expression of epithelial markers and reduced the levels of mesenchymal markers. Further studies revealed that the reintroduction of miR-449a attenuated the downstream signaling of Met, and consequently reduced the accumulation of Snail in cell nucleus by targeting the 3'-untranslated regions (3'-UTR) of FOS and Met. CONCLUSIONS: Our data highlight an important role of miR-449a in the molecular etiology of HCC, and implicate the potential application of miR-449a in cancer therapy.

The Effect of the Modified Eighth Section of Eight-Section Brocade on Osteoporosis in Postmenopausal Women: A Prospective Randomized Trial.

Osteoporosis and related fragility fractures represent a serious and global public health problem. To evaluate whether the modified eighth section of Eight-section Brocade (MESE) exercise could improve the symptom and indexes associated with osteoporosis in postmenopausal women. Guangzhou and Liuzhou hospital of traditional Chinese medicine in China. Women (n = 198) aged 50 to 75 years were randomized into Control, Ca, MESE, and MESE + Ca. Subjects in Ca and MESE groups were separately asked to consume thrice daily Calcium Carbonate Chewable D3 tablet and to perform thrice daily MESE exercise by 7 repetitions per time for 12 months. Subjects in MESE + Ca group performed such the combined treatment project for 12 months. Body height and Hospital for Special Surgery (HSS) scores of both knees, chronic back pain visual analogue scale scores (VAS), bone mineral density (BMD) at L2 to L4 and the left femoral neck, 3-feet Up and Go Test (3') and one-leg Stance (OLS). In our study, the improvement in chronic back pain of the patients in Ca, MESE, and MESE + Ca group was better than that in control group. There was 1.9% and 1.7%, 2.3%, and 2.1% net profit in left femoral neck and lumbar BMD after the treatment for 12 months in MESE and MESE + Ca groups. For the balance capacity, the subjects in MESE and MESE + Ca groups secured much better performance than those in Ca and control group after the treatment for 12 months (P < 0.001, P < 0.001). The treatment of MESE exercise is the most effective for the improvement of the symptom and indexes in postmenopausal women. Importantly, the low attrition and the high exercise compliance indicate that MESE exercise is safe, feasible, and well tolerated by postmenopausal women.

Hederagenin from the leaves of ivy (Hedera helix L.) induces apoptosis in human LoVo colon cells through the mitochondrial pathway.

BACKGROUND: Colorectal cancer has become one of the leading cause of cancer morbidity and mortality throughout world. Hederagenin, a derivative of oleanolic acid isolated from the leaves of ivy (Hedera helix L.), has been shown to have potential anti-tumor activity. The study was conducted to evaluate whether hederagenin could induce apoptosis of human colon cancer LoVo cells and explore the possible mechanism. METHODS: MTT assay was used for evaluating cell viability while Annexin V-FITC/PI assay and Hoechst 33342 nuclear stainining were used for the determination of apoptosis and mitochondrial membrane potential. DCFH-DA fluorescence staining and flow cytometry were used to measure ROS generation. Real-time PCR and western blot analysis were performed for apoptosis-related protein expressions. RESULTS: MTT assay showed that hederagenin could significantly inhibit the viability of LoVo cells in a concentration-dependent and time-dependent manner by IC50 of 1.39 µM at 24 h and 1.17 µM at 48 h. The apoptosis ratio was significantly increased to 32.46% and 81.78% by the induction of hederagenin (1 and 2 µM) in Annexin V-FITC/PI assay. Hederagenin could also induce the nuclear changes characteristic of apoptosis by Hoechst 33342 nuclear stainining under fluorescence microscopy. DCFH-DA fluorescence staining and flow cytometry showed that hederagenin could increase significantly ROS generation in LoVo cells. Real-time PCR showed that hederagenin induced the up-regulation of Bax and down-regulation of Bcl-2, Bcl-xL and Survivin. Western blotting analysis showed that hederagenin decreased the expressions of apoptosis-associated proteins Bcl-2, procaspase-9, procaspase-3, and polyADP- ribosepolymerase (PARP) were increased, while the expressions of Bax, caspase-3, caspase-9 were increased. However, there was no significant change on caspase-8. CONCLUSIONS: These results indicated that the disruption of mitochondrial membrane potential might contribute to the apoptosis of hederagenin in LoVo cells. Our findings suggested that hederagenin might be a promising therapeutic candidate for human colon cancer.

The anti-lung cancer activities of steroidal saponins of P. polyphylla Smith var. chinensis (Franch.) Hara through enhanced immunostimulation in experimental Lewis tumor-bearing C57BL/6 mice and induction of apoptosis in the A549 cell line.

P. polyphylla Smith var. chinensis (Franch.) Hara (PPSCFH) has been used as medicinal Paris for the prevention and treatment of cancers in China for thousands of years. Its main components, steroidal saponins (PRS), have been confirmed to inhibit tumor growth. In the present study, the immunostimulation of PRS was investigated in Lewis bearing-C57BL/6 mice while the induction of apoptosis in A549 cells was also studied. The treatment with PRS (2.5, 5.0 and 7.5 mg/kg) significantly inhibited tumor, volume, and weight in the C57BL/6 mice. The rates of inhibition of PRS (at 2.5, 5.0 and 7.5 mg/kg) were 26.49 ± 17.30%, 40.32 ± 18.91% and 54.94 ± 16.48%, respectively. The spleen and thymus indexes were increased remarkably, while the levels of inflammatory cytokines including TNF-α, IL-8 and IL-10 in serum were decreased according to ELISA assays. For A549 cells, Hoechst 33342 staining and annexin V/PI by flow cytometry showed that PRS (0.25, 0.50 and 0.75 mg/mL) induced nuclear changes of A549 cells with DNA condensation and fragmentations of chromatin, as well as inducing apoptosis. Furthermore, PRS could also attenuate the over-generation of intracellular ROS. Western blotting analysis showed a significant decrease on the expressions of proinflammatory cytokines MCP-1, IL-6 and TGF-ß1, as well as cell adhesion molecule ICAM-1, by treatment with PRS. Our results demonstrated that the inhibition of PRS on tumor growth might be associated with the amelioration of inflammation responses, induction of apoptosis, as well as the decrease of ROS. These results suggested that PRS implied a potential therapeutic effect in the lung cancer treatment.

[Clinical control study on postmenopausal osteoporosis treated with embedding thread according to syndrome differentiation and medication].

OBJECTIVE: To study the therapeutic efficacy of embedding thread according to staging and wholism syndrome differentiation and its effect on correlated indices of patients with postmenopausal osteoporosis. METHODS: 135 patients with postmenopausal osteoporosis were randomly assigned to the control group A (treated with Calcichew D3 Tablet), the control group B (treated with Calcichew D3 Tablet and Xianling Gubao Capsule), and the treatment group (treated with Calcichew D5 Tablet and embedding thread according to staging and wholism syndrome differentiation). The visual analogue scale (VAS), Chinese medicine syndrome integral, and the quality of life scale before treatment, 3 months after treatment, and 6 months after treatment were assessed. Changes of the lumbar bone mineral density (BMD) and the serum level of estradiol (E2) were also assessed before and after six-month treatment. And the therapeutic efficacy of each group was also assessed after 6 months of treatment. RESULTS: Before treatment, there was no significant difference in scores of VAS, Chinese medicine syndrome integral and the quality of life scale, the.serum level of E2, and the lumbar BMD of the patients in three groups (all P>0.05). After three months of treatment, there was significant difference in scores of VAS, Chinese medicine syndrome integral and the quality of life scale of the patients in the three groups (all P<0.01). Of them, the improvement of the three indices in the control group A was the worst in three groups (P< 0.05, P<0.01). The VAS in the treatment group was superior to those in control group B (P<0.01). But the difference of Chinese medicine syndrome integral and the quality of life scale was insignificant in the three groups. After six months of treatment, significant difference was shown in the scores of VAS, Chinese medicine syndrome integral, or the quality of life scale of the patients in the three groups when compared with the corresponding index before treatment and after three months of treatment (all P<0.01). Of them the improvement of the three indices of patients in the treatment group and the control group B was better than that in the control group A (all P<0.01), and the improvement in the treatment group were superior to that in the control group B (P<0.05, P<0. 01). Significant difference was shown in the serum level of E2 and the lumbar BMD of the patients in the treatment group and the control group B when compared with before treatment of the same group (both P<0.01). But there was no difference in the control group A between before and after treatment, with better effects obtained in the treatment group and the control group B. And the serum level of E, of the patients in the treatment group after treatment was higher than that in the control group B (P<0.01), but there was no difference in the lumbar BMD. The therapeutic efficacy in the treatment group and the control group B were superior to that in the control group A (P<0.01, P<0.05), but no difference existed between the treatment group and the control group B. CONCLUSIONS: The therapy of embedding thread according to staging and wholism syndrome differentiation could reduce the scores of VAS and Chinese medicine syndrome integral, enhance the serum lever of E2, the quality of life scale and the lumbar BMD of patients with postmenopausal osteoporosis. So it was an effective method.

[Postmenopausal osteoporosis of liver and kidney deficiency type treated with acupoint catgut embedding by stages].

OBJECTIVE: To explore the better treatment of postmenopausal osteoporosis of liver and kidney deficiency type. METHODS: One hundred and five cases were randomly divided into an observation group, a control group A and a control group B equally. In control group A, Calcichew D3 tablets were taken with oral administration; in control group B, Calcichew D3 tablets and Xianling Gubao capsule were taken with oral administration. In observation group, Calcichew D3 tablets and acupoint catgut embedding were applied; Shenshu (BL 23), Ganshu (BL 18), Jiaji (EX-B 2) and Weizhong (BL 40) etc. were selected at acute stage; Shenshu (BL 23) and Ganshu (BL 18) etc. were selected at remission stage, once every half a month and 6 months treatment in all. The Visual Analogue Scale (VAS), bone mineral density(BMD), estradiol (E2) and clinical effects were compared among groups. RESULTS: After 3 and 6 months treatment, the scores of VAS were reduced among groups (all P < 0.01); the reduction in observation group and control group B was superior to that in control group A (all P < 0.001), and it was more obvious in observation group than that in control group B (both P < 0.001). After 6 months treatment, lumbar BMD and the serum level of Ez improved obviously in observation group and control group B (all P < 0.01). The comparison among groups after treatment showed that the BMD in observation group and control group B was superior o o that in control group A (P < 0.01, P < 0.05); the serum level of E2 in observation group was superior to that in control group B and control group A (both P < 0.001), and it in control group B was superior to that in control group A. The total effective rate was 91.4% (32/35) in observation group, superior to that in control group A (57.1%, 20/35); and the total effective rate was 82. 9% (29/35) in control group B, superior to that in control group A. CONCLUSION: Calcichew D3 tablets and acupoint catgut embedding therapy can relieve the pain caused by postmenopausal osteoporosis of liver and kidney deficiency, improve the bone mineral density and serum level of estradiol; in brief, it is the better method.

[Controlled clinical trials on the treatment and prevention of shoulder and back fasciitis using horizontal bar exercises].

OBJECTIVE: To explore an exercise method for the prevention and treatment of the patients with shoulder and back fasciitis. METHODS: From 2006.8 to 2008.3, 120 patients with shoulder and back fasciitis were randomly divided into control group (n = 60, including 21 females and 39 males, the average age was (47.0 +/- 12.0) years, and the average course of disease was (14.1 +/- 12.0) months) and treatment group (n = 60,including 19 females and 41 males, the average age was (43.7 +/- 9.9) years, and the average course of disease was (16.4 +/- 13.4) months). The patients in the control group received massage therapy and the ones in the treatment group were treated with massage therapy and horizontal bar exercise. After 3 weeks treatment, the curative effects of the patients in two groups were observed. All the patients were followed up for 6 to 26 months, the recurrence were observed. RESULTS: After 3 weeks treatment, the scores of pain, sense of heaviness, strip sign, tenderness, shoulder and back function of the patients in two groups had significant differences compared with those before treatment (all P < 0.01). After treatment, the scores of pain, sense of heaviness, strip sign, tenderness, shoulder and back function of the patients in the treatment group were lower than those in the control group (P < 0.05). After 6 to 26 months following-up, the rate of recurrence in the treatment group was lower than that in the control group (P < 0.01). CONCLUSION: Horizontal bar exercise is a simple, no expense and effective method in the prevention and treatment of shoulder and back fasciitis, which can improve the effect of the treatment and reduce the rate of recurrence.

[Case-control study on embracing knee and rolling lumbar training for preventing and treating degenerative osteoarthritis of lumbar spine].

OBJECTIVE: To study therapeutic effects of embracing knee and rolling lumbar (EKRL) training on the pain and the function of lumbar of patients with degenerative osteoarthritis of lumbar spine. METHODS: From 2006.8 to 2008.1, 150 patients with degenerative osteoarthritis of lumbar spine were randomly divided into the control group, EKRL training group and the combined group. In the control group (n=50), there were 16 females and 34 males, the average age was (58.8 +/- 10.2) years and the average course of diseases was (16.3 +/- 14.9) months. In the EKRL training group (n=50), there were 13 females and 37 males, the average age was (60.1 +/- 8.2) years and the average course of disease was (17.1 +/- 15.3) months. In the combined group (n=50), there were 15 females and 35 males, the average ages was (59.9 +/- 11.4) years and the average course of diseases was (19.8 +/- 17.2) months. The patients in three groups were treated with Meloxicam tablets, EKRL training and two above methods combination respectively. After 3 weeks treatment, the curative effect, the visual analogous scores and the ODI indexes were observed. All the patients were followed up and the duration ranged from 6 to 24 months; the changes of average ODI indexes were observed monthly. RESULTS: After 3 weeks treatment, the therapeutic effects in three groups had obvious difference after Ridit analyses: there were significant differences between the combined group and other two groups (P<0.01), but no obvious differences existed in other two groups. Compared with before treatment, the visual analogue scale scores and the ODI indexes in three groups reduced significantly (P<0.01). After treatment, the visual analogue scale scores and the ODI indexes of the combined group had significant differences compared with those of other two groups (P<0.01), but the ODI indexes of other two groups had no obvious differences. After 6 to 24 months following-up, the monthly changes of average ODI indexes of EKRL training and combined groups had obvious differences compared with that of the control group (P<0.01). CONCLUSION: EKRL training is a simple, no expense and effective methods for preventing and treating degenerative osteoarthritis of lumbar spine.

[Observation on therapeutic effect of moxibustion on temperature-sensitive points for lumbar disc herniation].

OBJECTIVE: To compare therapeutic effects of traditional moxibustion and moxibustion on temperature-sensitive points for lumbar disc herniation. METHODS: One hundred and twenty cases were randomly divided into a temperature-sensitive point group and a traditional moxibustion group, 60 cases in each group. The temperature-sensitive point group was treated with moxibustion on the temperature-sensitive points in the temperature-sensitive high incidence area such as waist and lower limbs, once each day; the traditional moxibustion group was treated with warming moxibustion at Jiaji (EX-B 2), Ciliao (BL 32), Zhibian (BL 54), Huantiao (GB 30), Weizhong (BL 40), Yanglingquan (GB 34), Kunlun (BI. 60), once each day, 7 days constituting one course. The therapeutic effect and the recurrence rate were observed after one course treatment and six months later. RESULTS: After treatment for one course, the cured-markedly effective rate was 65.00% in the temperature-sensitive point group, superior to 50.0% in the traditional moxibustion group, with a significant difference between the two groups (P < 0.05); all effective cases were followed-up for six months, the cured-markedly effective rate and the recurrence rate were 62.3% and 26.4% in the temperature-sensitive point group, and 34.2% and 46.3% in the traditional moxibustion group, the therapeutic effect of the temperature-sensitive point group being superior to the traditional moxibustion group, and the recurrence rate was lower than the traditional moxibustion group (both P < 0.05). CONCLUSION: Moxibustion on temperature-sensitive points is a effective therapy for lumbar disc herniation, with stable therapeutic effect and low recurrence rate.

[Analysis of intermediate and long term clinical effects on discectomy with diskoscope].

OBJECTIVE: To estimate intermediate and long term clinical effects of lumbar intervertebral disc herniation on discectomy with diskoscope. METHODS: A hundred and nine patients with lumbar intervertebral disc herniation were retrospectively analyzed. The patietnts were operated with diskoscope. There were 61 males and 48 females. The age was from 25 to 68 years old with an average of 37.7 years. The affected region of patients were L(3,4) (5 cases), L(4,5) (42 cases), L5S1 (49 cases), L(4.5) and L5S1 (13 cases). Among them, 88 cases with single side and one segment, 13 cases with homolateral and two segments, 8 cases with hibateral and one segment were operated. The curative effects were followed up and estimated by recording satisfaction degrees at 1 year and 5.2 years(average) after operation. Moreover,intervertebral space height and the spinal stability of the patients were compared by imaging data before and after operation. RESULTS: At 1 year and 5.2 years (average) after operation,the scores by JOA standard were improved from 6.40 +/- 1.68 to 13.40 +/- 1.42, 13.15 +/- 1.35 (P < 0.01) respectively;the scores by VAS standard were reduced from 7.10 +/- 1.55 to 1.90 +/- 0.84, 2.10 +/- 0.58 (P < 0.01) respectively; the excellent and good rate was 91.7% (100/109) and 89.9% (98/109) respectively; the satisfaction degree of the patients was 95.4% and 94.5% respectively. The average time before working was 1 month. The imaging data of 45 patients were complete in the study, no lumbar instability sign were found. The loss rates of intervertebral space height were 57.8% (26/45), 93.3% (42/45) respectively at 1 year and 5.2 years (average) after operation. CONCLUSION: Discectomy with diskoscope has a good intermediate and long term clinical effects, it is a reliable method in the treatment of lumbar intervertebral disc herniation. It doesn't uncertainly cause instability of intervertebral space and root compression, though it can't avoid the loss of intervertebral space height.

Effects of sodium ferulate on human osteoarthritic chondrocytes and osteoarthritis in rats.

1. Oxidation, inflammation and apoptosis are involved in the aetiology and pathology of osteoarthritis (OA). Sodium ferulate (SF) has been demonstrated to have anti-oxidant, anti-inflammatory and anti-apoptotic actions in cardiovascular, hepatic and diabetic disorders. These findings suggest that SF may have beneficial effects on OA. Therefore, present study investigated the effects of SF in an in vivo rat OA model, as well as in vitro in human OA chondrocytes. 2. Rats were divided into the following groups: (i) an untreated control group; (ii) papain-induced OA; (iii) OA rats treated with 0.1 or 0.5% SF; and (iv) normal rats injected with 0.5% SF intra-articularly. Human chondrocytes from OA patients were cultured before being stimulated with 2 ng/mL interleukin-1ß and subsequently treated with SF (125, 250 and 500 µmol/L). The effects of SF were evaluated both in vivo and in vitro. 3. In OA rats, SF treatment dose-dependently reversed pathological changes in OA cartilage, decreased BAX-immunopositive chondrocytes and increased Bcl-2-immunopositive chondrocytes. Both in vivo and in vitro analyses demonstrated a significant decrease in matrix metalloproteinase-1 and an increase in tissue-specific inhibitor of metalloproteinase-1. In vitro, SF enhanced chondrocyte proliferation and decreased nitric oxide production and apoptosis. 4. The results demonstrate that SF dose-dependently suppresses pathological processes in both in vitro and in vivo OA models. Thus, SF could be a therapeutic strategy for the treatment of OA.