Prenatal lipopolysaccharide exposure induces anxiety-like behaviour in male mouse offspring and aberrant glial differentiation of embryonic neural stem cells.

BACKGROUND: Prenatal infection has been implicated in the development of neuropsychiatric disorders in children. We hypothesised that exposure to lipopolysaccharide during prenatal development could induce anxiety-like behaviour and sensorineural hearing loss in offspring, as well as disrupt neural differentiation during embryonic neural development. METHODS: We simulated prenatal infection in FVB mice and mouse embryonic stem cell (ESC) lines, specifically 46C and E14Tg2a, through lipopolysaccharide treatment. Gene expression profiling analyses and behavioural tests were utilized to study the effects of lipopolysaccharide on the offspring and alterations in toll-like receptor (TLR) 2-positive and TLR4-positive cells during neural differentiation in the ESCs. RESULTS: Exposure to lipopolysaccharide (25 µg/kg) on gestation day 9 resulted in anxiety-like behaviour specifically in male offspring, while no effects were detected in female offspring. We also found significant increases in the expression of GFAP and CNPase, as well as higher numbers of GFAP + astrocytes and O4+ oligodendrocytes in the prefrontal cortex of male offspring. Furthermore, increased scores for genes related to oligodendrocyte and lipid metabolism, particularly ApoE, were observed in the prefrontal cortex regions. Upon exposure to lipopolysaccharide during the ESC-to-neural stem cell (NSC) transition, Tuj1, Map2, Gfap, O4, and Oligo2 mRNA levels increased in the differentiated neural cells on day 14. In vitro experiments demonstrated that lipopolysaccharide exposure induced inflammatory responses, as evidenced by increased expression of IL1b and ApoB mRNA. CONCLUSIONS: Our findings suggest that prenatal infection at different stages of neural differentiation may result in distinct disturbances in neural differentiation during ESC-NSC transitions. Furthermore, early prenatal challenges with lipopolysaccharide selectively induce anxiety-like behaviour in male offspring. This behaviour may be attributed to the abnormal differentiation of astrocytes and oligodendrocytes in the brain, potentially mediated by ApoB/E signalling pathways in response to inflammatory stimuli.

[Construction of A Genetic Linkage Map in Salvia miltiorrhiza].

Objective: On the basis of previous studies, to construct a genetic map of Salvia miltiorrhiza by using EST-SSR primers, to build a platform for positioning important traits relating to genes, the cloning and molecular marker-assisted in breeding of new varieties of Salvia miltiorrhiza. Methods: A total of 411 EST-SSR primers were used for PCR amplification to screen polymorphic markers in F1 mapping population derived from a cross between Salvia miltiorrhiza, two parents of which were the cultivars of ZH74 and BH18. Combined with the molecular marker data of previous studies, Joinmap 4. 0 software was used for map integration. Results: 411EST-SSR primers were screened from two parents, a total of 328 pairs of primers were amplified stable products,164 pairs of polymorphic primers were obtained. Conclusion: A linkage map of Salvia miltiorrhiza with 150 marker high density genetic is constructed.

[Effect of Different Locations and Genotypes on Yield and Accumulation of Bioactive Constituents in Salvia miltiorrhiza].

Objective: The root yield and active constituent contents were analyzed from four Salvia miltiorrhiza cultivars grown at three different locations( Zhuyang, Changqing, and Taian, Shandong Province) to determine the influence of environmental conditions and cultivars. . Methods: Phenolic acids and tanshinones were analyzed by HPLC method. Total phenolic acids content were analyzed by FolinCiocalteu method. Klason method was used to determine the content of lignin. Results: The root yield and the active constituent contents were significantly affected by different environments and cultivars of Salvia miltiorrhiza. The root yield was negatively correlated with active constituent contents. Salvia miltiorrhiza of Zhuyang location had the highest active constituent content, but it had the lowest root yield. Salvia miltiorrhiza of Taian location had the lowest active constituent contents, while it had the highest root yield. Salvia miltiorrhiza of Changqing location had relatively higher bio-yields of phenolic acids and tanshinones, which made it suitable for Salvia miltiorrhiza cultivation. Furthermore, compared with three other cultivars,105 cultivar could remain the salvianolic acid B stable, which indicating that 105 cultivar was possible related to resistances. Conclusion: The research provides a theoretical basis for the selecting of the optimal cultivar and the optimal environmental condition.

[Construction of the first genetic linkage map of Salvia miltiorrhiza Bge. using SSR, SRAP and ISSR markers].

The first genetic linkage map of Salvia miltiorrhiza was constructed in 94 F1 individuals from an intraspecific cross by using simple sequence repeat (SSR), sequence-related amplified polymorphism (SRAP) and inter-simple sequence repeat (ISSR) markers. A total of 93 marker loci in the linkage map, consisting of 53 SSR, 38 SRAP and 2 ISSR locus were made up of eight linkage groups, covered a total length of 400.1 cm with an average distance of 4.3 cm per marker. The length of linkage groups varied from 3.3 -132 cm and each of them included 2-23 markers, separately. The result will provide important basis for QTL mapping, map-based cloning and association studies for commercially important traits in S. miltiorrhiza.

Characteristics and outcome of systemic treatment for metastatic or unresectable thymic carcinoma: A single institution experience.

BACKGROUND: Thymic carcinoma is a rare disease with an incidence of around 0.5 cases per million with a poor prognosis. The aim of this study was to assess patient outcomes with advanced thymic carcinoma receiving first-line chemotherapy. METHODS: In our retrospective cohort study, we included patients who underwent treatment for metastatic thymic carcinoma between January 2013 to December 2019 in our hospital. Overall survival, progression-free survival (PFS), objective response rates (ORR) and chemotherapy regimens were assessed and analyzed. RESULTS: A total of 27 patients were retrospectively analyzed. All patients received a platinum (cisplatin or carboplatin) based regimen as first-line chemotherapy (29.6% received ADOC, 11.1% received PE, 40.7% received CP, 14.8% received CAP). The median PFS on first-line chemotherapy was 199 days. The response rate was 40.7%. Median overall survival (OS) was 585 days. Positive CD5 staining was associated with better PFS. CONCLUSION: We highlight the critical role of platinum-based chemotherapy agents as a primary treatment modality in advanced thymic carcinoma, underscoring the efficacy of platinum as a first-line option for recurrent disease, even in cases previously treated with platinum. Additionally, our findings indicate that CD5 positivity could be associated with improved PFS, suggesting its potential as a prognostic marker.

Monoclonal Antibodies as a Therapeutic Strategy against Multidrug-Resistant Bacterial Infections in a Post-COVID-19 Era.

The development of severe multidrug-resistant bacterial infections has recently intensified because of the COVID-19 pandemic. According to the guidelines issued by the World Health Organization (WHO), routine antibiotic administration is not recommended for patients with supposed or confirmed mild SARS-CoV-2 infection or pneumonia, unless bacterial infection is clinically suspected. However, recent studies have pointed out that the proportion of non-essential antibiotic use in patients infected with SARS-CoV-2 remains high. Therefore, the silent pandemic of antibiotic resistance remains a pressing issue regardless of the present threats presented by the COVID-19 pandemic. To prevent or delay entry into the postulated post-antibiotic era, the long-term advocacy for the rational use of antibiotics, the optimization of infection control procedures, and the development of new antibacterial agents and vaccines should be underscored as vital practices of the antibacterial toolbox. Recently, the development of vaccines and monoclonal antibodies has gradually received attention following the advancement of biotechnology as well as enhanced drug discovery and development in cancer research. Although decent progress has been made in laboratory-based research and promising results have been obtained following clinical trials of some of these products, challenges still exist in their widespread clinical applications. This article describes the current advantages of antibacterial monoclonal antibodies, the development of associated clinical trials, and some perceived future perspectives and challenges. Further, we anticipate the development of more therapeutic agents to combat drug-resistant bacterial infections as well as to increase the resilience of current or novel agents/strategies.

Modified Experimental Conditions for Noise-Induced Hearing Loss in Mice and Assessment of Hearing Function and Outer Hair Cell Damage.

An animal model of noise-induced hearing loss (NIHL) is useful for pathologists, therapists, pharmacologists, and hearing researchers to thoroughly understand the mechanism of NIHL, and subsequently optimize the corresponding treatment strategies. This study aims to create an improved protocol for developing a mouse model of NIHL. Male C57BL/6J mice were used in this study. Unanesthetized mice were exposed to loud noises (1 and 6 kHz, presented simultaneously at 115-125 dB SPL-A) continuously for 6 h per day for 5 consecutive days. Auditory function was assessed 1 day and 1 week after noise exposure, using auditory brainstem response (ABR). After the ABR measurement, the mice were sacrificed, and their organs of Corti were collected for immunofluorescence staining. From the auditory brainstem response (ABR) measurements, significant hearing loss was observed 1 day after noise exposure. After 1 week, the hearing thresholds of the experimental mice decreased to ~80 dB SPL, which was still a significantly higher level than the control mice (~40 dB SPL). From the results of immunofluorescence imaging, outer hair cells (OHCs) were shown to be damaged. In summary, we created a model of NIHL using male C57BL/6J mice. A new and simple device for generating and delivering pure-tone noise was developed and then employed. Quantitative measurements of hearing thresholds and morphological confirmation of OHC damage both demonstrated that the applied noise successfully induced an expected hearing loss.

Early cholecystectomy following percutaneous transhepatic gallbladder drainage is effective for moderate to severe acute cholecystitis in the octogenarians.

BACKGROUND: Acute cholecystitis (AC) is a life-threatening infectious/inflammatory disease in older patients. This study aimed to investigate the safety and optimal timing of surgery in patients aged ≥ 80 years with moderate to severe AC who received percutaneous transhepatic gallbladder drainage (PTGBD). METHODS: From January 2008 to February 2021, 152 patients were retrospectively enrolled. Clinical outcomes were compared among patients who received laparoscopic cholecystectomy (LC), open cholecystectomy (OC), and conversion surgery, and between those who received early (< 6 weeks after PTGBD) and delayed cholecystectomy (≥ 6 weeks after PTGBD). Logistic regression analysis was used to identify risk factors for recurrent AC, further biliary events, conversion, and perioperative complications. RESULTS: Sixty-seven patients underwent LC, 62 underwent OC, and 23 underwent conversion surgery. Operation-related complications and mortality rates did not differ among the types of surgery; however, LC group had shorter operative time than the other groups. Eighty-two patients underwent early cholecystectomy, while 70 underwent delayed cholecystectomy. There were no differences in operative time, operation-related complications, and mortality rates between the groups. However, higher rates of recurrent AC and biliary events were observed in the delayed cholecystectomy group (52.9% vs. 4.9% and 57.1% vs. 8.5%, p < 0.001). On multivariate analysis, delayed cholecystectomy was a significant risk factor for recurrent AC (odds ratio [OR] = 19.42, p < 0.001) and further biliary events (OR = 15.95, p < 0.001). CONCLUSIONS: Early cholecystectomy is recommended for patients aged ≥ 80 years with moderate to severe AC following PTGBD.

Elizabethkingia anophelis outer membrane vesicles as a novel vaccine candidate against infection: insights into immune response and potential for passive immunity.

IMPORTANCE: Elizabethkingia anophelis, a Gram-negative pathogen, causes infections such as bacteraemia, pneumonia, and neonatal meningitis. The pathogen resists most antimicrobial classes, making novel approaches urgently needed. In natural settings, Gram-negative bacteria secrete outer membrane vesicles (OMVs) that carry important molecules in the bacterial life cycle. These OMVs are enriched with proteins involved in virulence, survival, and carbohydrate metabolism, making them a promising source for vaccine development against the pathogen. This study investigated the efficacy of imipenem-induced OMVs (iOMVs) as a vaccine candidate against E. anophelis infection in a mouse pneumonia model. Mice immunized with iOMVs were completely protected during lethal-dose challenges. Passive immunization with hyperimmune sera and splenocytes conferred protection against lethal pneumonia. Further investigation is needed to understand the mechanisms underlying the protective effects of iOMV-induced passive immunity, such as the action on specific antibody subclasses or T cell subsets.

Outcomes of patients with malignant esophagogastric junction obstruction receiving metallic stents: A single-center experience.

BACKGROUND: Malignancies-related esophagogastric junction (EGJ) obstruction is usually diagnosed in inoperable status with poor clinical outcomes. Metallic stent placement at EGJ could improve dysphagia for these patients. However, studies regarding the outcomes in these patients receiving metallic stents are still limited. This study aimed to investigate the outcomes of metallic stent placement in malignant EGJ obstruction. METHODS: Forty-one patients with inoperable malignant EGJ obstruction receiving metallic stent placement were retrospectively enrolled. The clinical outcomes between different stents and deployment techniques were analyzed. RESULTS: The overall technical success rate was 97.6% and clinical success rate was 92.1%. The median overall survival time was 77 (4-893) days, and the patency time was 71 (4-893) days, respectively. Poststent radiotherapy significantly prolonged survival and stent patency. Between patients receiving uncovered or partially covered metal stents, there was no difference in procedure-related complications, survival time, and stent patency time. Moreover, the clinical outcomes in patients receiving duodenal stents for malignant EGJ obstruction are not inferior to those receiving esophageal stents. CONCLUSION: This study provides crucial information for endoscopists to establish individualized stenting strategies for malignant EGJ obstruction.

Generation of induced pluripotent stem cells FIRDIi001-A from a Taiwanese subject carrying ALDH2 pE487K mutation.

The ALDH2 mutation (ALDH2*2) is caused by an amino acid substitution ALDH2 rs671 G>A (pE487K) which reduces ALDH2 enzyme activity. When individuals with the ALDH2 mutation consume alcohol, accumulating acetaldehyde in the blood can cause reddened face, headache, nausea, and palpitations; symptoms referred to as Alcohol Flushing Reaction. We report the production of an induced pluripotent stem cell (iPSC) line, FIRDIi001-A, developed from peripheral blood mononuclear cells of a 39-year-old male subject with the ALDH2*2 mutation. The ALDH2-pE487K iPSCs will be valuable in investigating pathogenic mechanisms involved in the link between the ALDH2 polymorphism and alcohol-related diseases.

Generation of induced pluripotent stem cells MMCi001-A from a Taiwanese hearing loss patient carrying GJB2 pV37I mutation.

Hearing loss is the most common disorder in the sensory system. Mutations in GJB2 have been reported to be very common in sensorineural hearing loss patients. In this report, we generated an induced pluripotent stem cell (iPSC) line, MMCi001-A, from the peripheral blood mononuclear cells of a 4-year-old male hearing loss patient carrying GJB2 pV37I mutation by using the Sendai virus delivery system. The generated iPSCs were demonstrated to express pluripotent markers and be differentiated into three germ layers in vitro and in vivo. This GJB2-pV37I iPSCs is valuable for studying the pathogenic mechanisms and drug discovery of hearing loss.

Isoflurane attenuates carbogen-induced blood-brain barrier disruption independent of body temperature in mice and rats.

Isoflurane protects the blood-brain barrier (BBB) against cerebral extravasation of Evans blue dye (EBD), a commonly used serum protein tracer, in animals subjected to BBB disruption. As such, it has been implicated as a therapeutic agent that can prevent brain edema and damage caused by a number of brain insults, including focal ischemia and subarachnoid hemorrhage. Recently, it has been shown that isoflurane inhibits the cerebral extravasation of EBD following ischemic stroke chiefly by inducing hypothermia, raising the intriguing possibility that isoflurane protected against other causes of BBB disruption also through hypothermia. To test this hypothesis, we subjected mice and rats to inhalation of 20-30% carbogen, an inducer of BBB disruption, in the presence or absence of isoflurane while measuring their rectal temperature. In mice, carbogen inhalation on its own decreased rectal temperature from 36.4 ± 0.4 to 26.2 ± 0.6°C over a period of 60 minutes, and under this condition, isoflurane had no additional effect on body temperature. Nevertheless, isoflurane protected against carbogen-induced cerebral extravasation of EBD. In addition, when the body temperature was maintained in the normothermic range using an automated heating pad, isoflurane remained protective against cerebral extravasation of EBD. In rats, isoflurane also protected against cerebral extravasation of EBD, while having no effect on plasma pH, electrolyte concentrations, or osmolarity. In conclusion, isoflurane protected against BBB disruption caused by carbogen inhalation in mice and rats, but unlike isoflurane-mediated protection against ischemic BBB disruption, the effect could not be explained by anesthesia-induced hypothermia.

Validation and reliability of Falls Risk for Hospitalized Older People (FRHOP): Taiwan version.

A comprehensive fall risk assessment can provide information for effective prevention and intervention measures and reduce falls among hospitalized elderly people. The purpose of this study was to develop a Chinese version of an inpatient fall risk assessment tool and evaluate its validity and reliability.This study employed the Falls Risk for Hospitalised Older People (FRHOP) assessment to construct a FRHOP-Taiwan Version (Tw-FRHOP) through forward, synthesized, and backward translation. A face validation was conducted by 5 clinical nurses and a content validation was conducted by 5 specialists using the content validity index (CVI) to validate the proposed model. Thirty hospitalized older adults in an internal care unit were selected for an interrater reliability assessment, conducted separately by specialists in 4 disciplines (i.e., nurses, physicians, occupational therapists, and physiotherapists) by using Cohen kappa statistic and intraclass correlation coefficients (ICCs). Specifically, the assessment rating developed in the Tw-FRHOP was compared with the Morse Fall Scale (MFS), St. Thomas Risk Assessment Tool in Falling Elderly Inpatients (STRATIFY), and the Hendrich II Fall Risk Model (HIIFRM) for criterion validation.According to the analysis results, the CVI was 0.94, and the indexes of criterion-related validity for the FRHOP-Taiwan Version, MFS, STRATIFY, and HIIFRM were 0.49, 0.63, and 0.54 (all P < .001), respectively. In addition, after interrater reliability testing was conducted, the results indicated that the index of response consistency in each discipline was 86.7% to 100%, and the values of Cohen kappa were 0.651 to 1.000. The ICCs of the discipline-related subscale were 0.97 to 1.00.The Tw-FRHOP is a multidisciplinary comprehensive fall risk assessment that can serve as a satisfactorily valid and reliable reference tool for medical personnel with full professional training, as well as inpatient fall prevention interventions for multidisciplinary teams in hospitals.

Anesthesia-Induced Hypothermia Attenuates Early-Phase Blood-Brain Barrier Disruption but Not Infarct Volume following Cerebral Ischemia.

Blood-brain barrier (BBB) disruption is thought to facilitate the development of cerebral infarction after a stroke. In a typical stroke model (such as the one used in this study), the early phase of BBB disruption reaches a peak 6 h post-ischemia and largely recovers after 8-24 h, whereas the late phase of BBB disruption begins 48-58 h post-ischemia. Because cerebral infarct develops within 24 h after the onset of ischemia, and several therapeutic agents have been shown to reduce the infarct volume when administered at 6 h post-ischemia, we hypothesized that attenuating BBB disruption at its peak (6 h post-ischemia) can also decrease the infarct volume measured at 24 h. We used a mouse stroke model obtained by combining 120 min of distal middle cerebral arterial occlusion (dMCAo) with ipsilateral common carotid arterial occlusion (CCAo). This model produced the most reliable BBB disruption and cerebral infarction compared to other models characterized by a shorter duration of ischemia or obtained with dMCAO or CCAo alone. The BBB permeability was measured by quantifying Evans blue dye (EBD) extravasation, as this tracer has been shown to be more sensitive for the detection of early-phase BBB disruption compared to other intravascular tracers that are more appropriate for detecting late-phase BBB disruption. We showed that a 1 h-long treatment with isoflurane-anesthesia induced marked hypothermia and attenuated the peak of BBB disruption when administered 6 h after the onset of dMCAo/CCAo-induced ischemia. We also demonstrated that the inhibitory effect of isoflurane was hypothermia-dependent because the same treatment had no effect on ischemic BBB disruption when the mouse body temperature was maintained at 37°C. Importantly, inhibiting the peak of BBB disruption by hypothermia had no effect on the volume of brain infarct 24 h post-ischemia. In conclusion, inhibiting the peak of BBB disruption is not an effective neuroprotective strategy, especially in comparison to the inhibitors of the neuronal death signaling cascade; these, in fact, can attenuate the infarct volume measured at 24 h post-ischemia when administered at 6 h in our same stroke model.

[Significance of Morphological Examination, Cytochemical Staining Combined with Bone Marrow Biopsy in Differential Diagnosis of Myelodysplastic Syndrome with Low Blasts and Hemolytic Anemia].

OBJECTIVE: To explore the value of morphological examination, cytochemical staining combined with bone marrow biopsy in the differential diagnosis between myelodysplastic syndrome (MDS) with low blasts and hemolytic anemia (HA). METHODS: The clinical data of 85 cases of myelodysplastic syndrome with low blasts (< 5%) and 61 patients with hemolytic anemia in Chinese PLA's Gerneral hospital from September 2009 to March 2015 were retrospectively analysed. The clinical characteristics, cytogenetic and molecular features, bone marrow cell count and morphology features, cytochemical staining results and bone marrow biopsy features of above-methioned patients were compared. RESULTS: There was no significant difference (P > 0.05) in clinical data between MDS group and HA group. Megakaryocytic dysplasia-positive rate, and ring sideroblasts positive rate, and PAS positive rate were significantly higher in MDS group than those that in HA group (P < 0.05). Abnormal localization of immature precursors (ALIP) and megakaryocytic dysplasia positive rate in bone marrow biopsy were significantly higher in MDS group than those that in HA group (P < 0.05), 90.6% of MDS with low blasts patients were identifiable by combined detections. CONCLUSION: Combining detection of morphology, cytochemistry staining and bone marrow biopsy has been confirmed to be more useful for differential diagnosis between MDS with low blasts and HA.

[Clinical significance of bone marrow morphological examination and tumor marker detection for lymphoma diagnosis and prognosis].

OBJECTIVE: This study was aimed to evaluate the significance of bone marrow(BM) morphological examination and many tumor marker(TM) detection, especially carcinoembryonic antigen (CEA), cancer antigen 125(CA125), cancer antigen 15-3 (CA15-3) and serum ferritin (SF) for lymphoma diagnosis and prognosis. METHODS: A total of 47 confirmed patients with lymphoma in our hospital from January 2012 to October 2013 and 20 health peoplels as normal controls were performed with bone marrow morphological examination, at the same time, the electrochemistry luminescent technique was applied for detecting levels of TM (especially CEA, CA125, CA15-3 and SF) in serum samples of lymphoma patient and normal controls, then the BM immature lymphocyte counts of these people and clinical parameters were analyzed for diagnosis and prognosis. RESULTS: There was significant differences in all the four TM levels between serum samples of lymphoma patients and normal control (P=0.029, P=0.000, P=0.005, P=0.000). These TM levels had no correlation with age, sex white blood cell, lymphocyte, platelet counts and anemia of lymphoma patients (P>0.05). It was also found that the patients with elevated TM levels had high BM immature lymphocytes (lymphoma cells) counts, B symptoms, advanced clinical stage and high IPI index (P<0.05). The CA15-3 and SF levels in serum samples of lymphoma patients with BM infiltration were higher than that in lymphoma patients without BM infiltration (P=0.002, P=0.000). CONCLUSION: Combination of BM morphological examination with serum TM level detection plays an important role in diagnosis, clinical stage and prognosis evaluation of lymphoma patients. It is also very important for assessing BM infiltration status of lymphoma patients.

New taxane diterpenoids from the leaves and twigs of Taxus sumatrana.

Two new taxoids, taxumairol Q (1) and 13-O-acetyl wallifoliol (2), have been isolated from the leaves and twigs of Taxus sumatrana. Taxuspine F and wallifoliol (10) have been isolated for the first time from the yew T. sumatrana. Seventeen known taxoid diterpenoids have also been isolated. The new derivatives, 9,13-diacetyltaxumairol W (3), 10,13-dibenzoyltaxacustin (4), 7,13-diacetylwallifoliol (5), 7,13-dibenzoylwallifoliol (6), and 7,9-dibenzoyltaxumairol P (7), have been prepared by acylation of a crude mixture of taxoids. All structures were established primarily on the basis of 1D and 2D NMR techniques, including DEPT, COSY, and HMBC experiments, as well as chemical correlation with known compounds. Wallifoliol (10) exhibited significant cytotoxicities against both Hepa 59 T/VGH (human liver carcinoma) and KB (human oral epidermoid carcinoma) tumor cells. Taxuspine F and compound 5 possessed moderate activity against Hepa cells only, while 3, 6, 7, and 10-deacetylbaccatin III showed only marginal activity against Hepa cells.

New taxane diterpenoids from Taiwanese Taxus sumatrana.

Two new taxane diterpenoids, tasumatrols A (1) and B (2), have been isolated from extracts of the leaves and twigs of Taiwanese Taxus sumatrana. Tasumatrol A is a rare 5/6/6 taxene system, having a novel gamma-lactone at C-10 and C-19. The structures of compounds 1 and 2 were determined on the basis of two dimensional (2D)-NMR techniques, including correlation spectroscopy (COSY), 1H-detected heteronuclear multiple quantum coherence (HMQC) and heteronuclear multiple bond connectivity (HMBC) experiments.