Phenolic and flavonoid compounds from the fruit shell of Camellia oleifera

A new phenolic compound oleiphenol (1), and a new dihydrochalcone oleifechalcone (2) along with seven known compounds (3-9) were isolated from the fruit shell of Camellia oleifera Abel. The planar structures of compounds 1 and 2 were determined on the basis of extensive spectroscopic analyses (IR, UV, NMR, and HR-ESI-MS) and comparison with literature data. The absolute configurations of the new structures were determined by ECD calculations and chemical methods. In addition, compounds 1-9 underwent a series of pharmacological activity tests, including cytotoxic, anti-inflammatory, anti-RSV and antioxidant activities.

Two new pregnane glycosides from the root of Cynanchum auriculatum

Two new pregnane glycosides (1 and 2), together with four known ones (3- 6), were isolated from the roots of Cynanchum auriculatum Royle ex Wight (Asclepiadaceae). On the basis of detailed spectroscopic analysis and chemical method, the structures of new compounds were characterized to be metaplexigenin 3-O-β-D-cymaropyranosyl- (1→4)-α-L-diginopyranosyl-(1→4)-β-D-cymaropyranoside (1), metaplexigenin 3-O-α-L-diginopyranosyl-(1→4)-β-D-cymaropyranoside (2). All the isolated compounds (1-6) were tested for their in vitro inhibitory activity against the growth of human colon cancer cell lines HCT-116. Compounds 5 and 6 showed significant cytoxicities with IC50 values of 43.58 µM and 52.21 µM.

Two new chemical constituents from the stem and branch of Tripterygium wilfordii

A chemical investigation of 95% ethanol extract from the stem and branch of Tripterygium wilfordii has resulted in the isolation and characterization of two new compounds, one neolignan (1) and one phenylalanine derivative (2), as well as four known compounds (3-6). The structures of the new compounds were determined based on extensive spectroscopic analyses. The absolute configuration of compound 1 was defined by X-ray crystallographic analyses and electronic circular dichroism calculation. In addition, compounds 2 and 4-6 exhibited inhibitory effects against NO production in LPS-induced RAW 264.7 macrophages with the IC50 value ranging from 3.51 μM to 30.40 μM.

[Effects of free superficial peroneal artery perforator flap in repairing small and medium-sized thermal crush injury wounds in the hand]

Objective: To investigate the surgical methods and clinical effects of free superficial peroneal artery perforator flap in repairing small and medium-sized thermal crush injury wounds in the hand. Methods: A retrospective observational study was conducted. From August 2018 to December 2021, 12 patients (19 wounds) with small and medium-sized thermal crush injury in the hand who met the inclusion criteria were hospitalized in Suzhou Ruihua Orthopaedic Hospital, including 5 males and 7 females, aged from 30 to 54 years. The area of the wound was from 2.5 cm×2.0 cm to 14.0 cm×3.5 cm, and all the wounds were repaired by using free superficial peroneal artery perforator flaps from lower leg on one side (including single flap, multiple flaps, and multiple flaps with one pedicle resected from the same donor site). The area of the flap was from 3.5 cm×3.0 cm to 16.0 cm×4.0 cm. The wound in the donor site was sutured directly. The vascular crisis and survival of the flap were observed after operation. The texture, appearance, color, hyperpigmentation, sensation, and two-point discrimination of the flap repaired area were followed up, as well as the hyperplasia of scar and pain condition in the donor and recipient sites. At the last follow-up, the curative effect of flap repair was evaluated by the comprehensive evaluation scale, and the extension and flexion functions of the reserved digital joint were evaluated by the total active movement systematic evaluation method recommended by American Academy for Surgery of Hand. Results: One flap developed arterial crisis on the first day after operation but survived after timely exploration. The other 18 flaps survived successfully after operation. Follow-up of 4 to 24 months after operation showed good texture and appearance in the flap repaired area; the color of the flap repaired area was similar to that of the normal skin around the recipient site, without pigmentation; the protective sensation was restored in all cases, but there was no two-point discrimination; there was no obvious hypertrophic scarring or pain in the donor or recipient site. At the last follow-up, the curative effect of flap repair was evaluated with 3 flaps being excellent and 16 flaps being good; the extension and flexion functions of the reserved digital joint were also assessed, being excellent in 8 fingers, good in 9 fingers, and fair in 2 fingers. Conclusions: The blood supply of superficial peroneal artery perforator flap is sufficient and reliable, and multiple flaps of this type or multiple flaps with one pedicle can be resected from one donor site. The use of this flap to repair small and medium-sized thermal crush injury wounds in the hand results in minimal damage to the donor area, and good postoperative appearance and texture of the flap.

Two new aryltetralin-type lignans from Camellia oleifera husk

Two new aryltetralin-type lignans (1-2) were isolated from the dichloromethane fraction of 95% ethanol extract of Camellia oleifera fruit husk. Their structures were elucidated on the basis of spectroscopic analysis, and the absolute configurations of compounds 1-2 were determined by the comparison of measured ECD curves with the quantum chemical calculated ones. The new compounds were tested for their antioxidant activities and cytotoxicity against three human cancer cell lines (Huh-7, H460 and MCF-7). While compounds 1 and 2 only showed slight DPPH radical scavenging activities with the IC50 values of 38.68 ± 5.02 and 56.62 ± 1.49 μM, respectively.

[Clinical effects of proximal ulnar artery perforator flap combined with iliac bone graft in the reconstruction of subtotal thumb or finger defects]

Objective: To explore the clinical effects of proximal ulnar artery perforator flap combined with iliac bone graft in the reconstruction of subtotal thumb or finger defects. Methods: A retrospective observational study was conducted. From August 2016 to August 2019, 7 patients with thumb or finger defects caused by mechanical damage who met the inclusion criteria were admitted to Ruihua Affiliated Hospital of Soochow University, including 6 males and 1 female, aged 46 to 58 years. Their length of fingers was repaired with iliac bone, with length of 2.0 to 3.0 cm. After the bone graft, the skin defect area of the affected finger ranged from 2.8 cm×2.2 cm to 6.0 cm×3.2 cm. Then the free proximal ulnar artery perforator flap with area of 3.0 cm×2.4 cm to 6.5 cm×3.5 cm was used to cover the wounds. The wounds in donor sites of iliac crest and flap were directly sutured. The survival of flap in one week post surgery and the donor site wound healing in 2 weeks post surgery were observed, respectively. During the follow-up, the appearance and sensory function of the affected finger, bone healing, and scar hypertrophy of wound in the donor site were observed and evaluated. At the last follow-up, the functional recovery of the affected finger was evaluated with trial standard for the evaluation of functions of the upper limbs of the Hand Surgery Society of Chinese Medical Association. Results: In one week post surgery, all the flaps survived. In 2 weeks post surgery, the iliac bone and the wounds in forearm donor site healed. During the follow-up of 5 to 13 months, the flap was good in appearance, without obvious pigmentation; the sensory recovery reached level S2 in 5 patients and S0 in 2 patients; all the grafted iliac bones were bony union without obvious resorption; the wounds in donor site healed well, with only mild scar formation. At the last follow-up, the shape of the reconstructed finger was close to the healthy finger, and the functional evaluation results were excellent in 3 cases and good in 4 cases. Conclusions: The use of proximal ulnar artery perforator flap combined with iliac bone graft to reconstruct subtotal thumb or finger can partially restore part of the appearance and function, with less damage to the donor site. It is a good choice for patients who have low expectations of appearance and function for the reconstructed finger.

Undescribed abietane-type diterpenoids and oleanane-type triterpenoids from the stem and branch of Tripterygium wilfordii

Six undescribed abietane-type diterpenoids (tripterydinoids A-F) and five undescribed oleanane-type triterpenoids (tripterytrinoids A-E) were obtained and determined from the stem and branch of Tripterygium wilfordii Hook. f. (Celastraceae). Tripterydinoids A-C possessed the abietane-type diterpenoid skeleton with rare 8, 9-epoxy ring. The structures of undescribed compounds were established by extensive spectroscopic studies [HRESIMS, 1D/2D-NMR and electronic circular dichroism (ECD) calculation]. The absolute configurations of tripterydinoids A, B, E and tripterytrinoid A were defined by X-ray crystallographic analyses. Bioactivity screening indicated that tripterydinoids A-C exhibited potent inhibitory effects against NO release in LPS-activated RAW 264.7 macrophages with IC₅₀ values of 6.93, 4.46 and 2.98 μM, respectively. Meanwhile, tripterydinoids A-D and tripterytrinoids B, C showed moderate and selective cytotoxicities against five human tumor cell lines (A375, Huh7, MCF-7, HCT-116 and NCI-H460).

[Clinical and prognostic features of ovarian endometrioid carcinoma with synchronous endometrial lesions]

Objective: To compare the clinical and prognostic characteristics of ovarian endometrioid carcinoma (OEC) patients with synchronous endometrial lesions and patients with pure OEC. Methods: A retrospective review of the medical records of patients received initial treatment and a postoperative pathological diagnosis of OEC at Peking University People's Hospital between August 1998 and December 2017 were performed. According to the inclusion criteria, a total of 56 patients with OEC were included in the study, including 13 patients concurrent with simultaneous endometrial lesions (Group A) and 43 patients with pure OEC (Group B). Results: Patients with synchronous endometrial lesions accounted for 23% (13/56). Mean age of Group A at diagnosis was (44.9±8.3) years old, 2/13 of patients were postmenopausal, and no one had a history of hypertension, the first symptom of 5/13 people was irregular vaginal bleeding. Mean age of Group B patients at diagnosis was (52.7±10.2) years old, 53% (23/43) of patients were postmenopausal, and 28% (12/43) patients had the history of hypertension, the first symptom of 4 (9%, 4/43) people was irregular vaginal bleeding. The differences of age, menopause status, history of hypertension and initial symptoms between the two groups were statistically significant (all P<0.05). There were no significant differences in fertility history, dysmenorrhea history, age of menarche, history of endometriosis, preoperative and postoperative CA₁₂₅ level, International Federation of Gynecology and Obstetrics (FIGO) stage, tumor grade, metastatic site and platinum-based chemotherapy drug resistance between the two groups (all P>0.05). The overall 5-year survival rate of OEC patients was 91.6%, and the overall 5-year progression-free survival rate was 76.6%. Among them, the 5-year survival rate of the OEC concurrent with simultaneous endometrial lesions group was 80.2%, and the pure OEC group was 93.4%; the 5-year progression-free survival rate of the OEC concurrent with simultaneous endometrial lesions group was 74.1%, and the 5-year progression-free survival rate of the pure OEC group was 77.3%. There were no significant differences between the two groups (all P>0.05). Multivariate analysis showed that the independent factors for the prognosis of OEC patients were FIGO stage (P=0.006) and residual lesion size (P=0.020). Conclusions: OEC patients have a high proportion of simultaneous endometrial lesions. OEC with simultaneous endometrial lesions are younger than patients with pure OEC. Synchronous endometrial lesions do not affect the prognosis of patients with OEC.

[Preliminary study of PD-1 inhibitor in the treatment of drug-resistant recurrent gestational trophoblastic neoplasia]

Objective: To investigate the therapeutic effect of programmed cell death receptor 1 (PD-1) inhibitor in drug-resistant recurrent gestational trophoblastic neoplasia (GTN). Methods: Clinicopathological features, previous treatments, PD-1 inhibitor treatment and prognosis of 8 patients with drug-resistant recurrent GTN treated with PD-1 inhibitor pembrolizumab， in Peking Union Medical College Hospital of Chinese Academy of Medical Sciences from August 2018 to June 2019 were collected and retrospectively analyzed. Results: (1) Clinicopathological features: the average age of onset of 8 GTN patients was 32.9 years old (31-39 years old); pathological types: choriocarcinoma in 7 cases, epithelioid trophoblastic tumor in 1 case. International Federation of Gynecology and Obstetrics (FIGO) stages: stage Ⅲ in 5 cases, stage Ⅳ in 3 cases; FIGO score: 4 patients with 7-12 points (high-risk group) and 4 patients with ≥13 points (ultra high-risk group). All the 8 patients had lung metastasis, 2 patients with brain metastasis, 1 patient with kidney and 1 patient with intestinal metastasis. (2) Previous treatments: ① Chemotherapy: 8 patients with GTN received an average of 21.1 courses (5-30 courses) of chemotherapy; the main route was systemic intravenous chemotherapy. One patient received intrathecal methotrexate chemotherapy due to brain metastasis. ② Surgery: 7 of 8 patients with GTN received surgical treatment, including 5 cases of pelvic surgury, 6 cases of pulmonary lobectomy and 1 case of right hemicolectomy. ③ Radiotherapy: 2 of 8 patients with GTN received radiotherapy, among which 1 patient received radiotherapy for lung for 8 times due to lung metastasis, and the other one received radiotherapy for lung, right sacroiliac joint and skull for a total of 22 times. (3) PD-1 inhibitor treatment: 8 patients with GTN received PD-1 inhibitor treatment with a mean course of 9 (2-12 courses). Six patients appeared Ⅰ-Ⅱ grade of immune related adverse events (AE), and no severe AE occurred. (4) Prognosis: after 2-3 courses of PD-1 inhibitor treatment, serum β-hCG level came to normalization in 4 patients. They were followed up for 2-7 months without any recurrence after 0-9 courses of consolidation treatment. One patient received 12 courses of PD-1 inhibitor treatment. The serum β-hCG level normalized after the 6th courses but increased 1 months later, and then received bevacizumab treatment due to the progression of the disease. The remaining 3 patients received other chemotherapy regiments due to disease progression during PD-1 inhibitor treatment. Conclusions: PD-1 could be used as a remedial treatment for drug-resistant recurrent GTN, with a high effective rate and relatively mild AE. However, more cases need to be accumulated clinically and efficacy should be comprehensively evaluated in combination with pathology and immunohistochemical examination.

[The efficacy analysis of allogeneic hematopoietic stem cell transplantation in 48 leukemia patients with central nervous system leukemia]

目的

探讨异基因造血干细胞移植（allo-HSCT）治疗合并中枢神经系统白血病（CNSL）患者的疗效。

方法

对2012年5月至2017年12月收治的48例合并CNSL患者进行回顾性分析。

结果

①全部48例患者中，男38例，女10例，中位年龄20（6~48）岁；急性淋巴细胞白血病（ALL）22例，急性髓系白血病（AML）21例，慢性髓性白血病（CML）5例。移植前骨髓完全缓解（CR）19例（CR组），未缓解（NR）29例（NR组）。②预处理方案：成人采用以全身照射（TBI）为主方案，其中6例患者联合全脑全脊髓放疗，2例患者联合射波刀治疗；儿童患者采用改良伊达比星（IDA）联合Bu-Cy（白消安+环磷酰胺）方案。③48例患者均顺利植活，粒细胞植活中位时间为14（10~23）d，血小板植活的中位时间为16（6~78）d。④移植后28天评估骨髓，48例患者均达CR，经DNA检测证实均为完全供者嵌合状态。⑤中位随访时间为14（2~69）个月，28例患者存活，10例复发，其中CNSL复发3例。移植前CR组、NR组allo-HSCT后1年总生存（OS）率分别为（77.3±10.0）%、（57.6±9.3）%（P=0.409），无病生存率（DFS）分别为（71.2±11.0）%、（53.9±9.5）%（P=0.386）。ALL、AML组移植后1年OS率分别为（54.2±10.7）%、（80.1±8.9）%（P=0.200），DFS率分别为（49.2±10.8）%、（75.0±9.7）%（P=0.190）。

结论

allo-HSCT治疗CNSL是安全、有效的。

[Effects of CD34(+) selected stem cells for the treatment of poor graft function after allogeneic stem cell transplantation]

目的

观察输注纯化供者CD34⁺细胞治疗单倍型造血干细胞移植后移植物功能不良的疗效和安全性。

方法

对2014年1月至2018年3月期间接受供者纯化CD34⁺细胞治疗的12例单倍型造血干细胞移植后移植物功能不良患者进行回顾性分析。

结果

12例患者中男9例、女3例，中位年龄26（14~54）岁；急性淋巴细胞白血病4例，急性髓系白血病5例，慢性髓性白血病2例，慢性粒-单核细胞白血病1例。分选产物CD34⁺细胞纯度为92.0%（44.0%~97.0%），回收率为55.0%（45.0%~96.7%），回输CD34⁺细胞的中位数为1.9（0.9~4.4）×10⁶/kg，CD3⁺细胞中位数为0.6（0.3~2.0）×10⁴/kg。中性粒细胞恢复中位时间为18（14~39）d，血小板恢复中位时间为29（16~153）d，红细胞恢复中位时间为60（9~124）d。12例患者输注过程中未发生严重不良反应，10例获得完全缓解，1例患者获得部分缓解，1例患者无效，未发生重症感染和重度GVHD。

结论

回输供者纯化CD34⁺细胞是单倍型造血干细胞移植后植入功能不良的一种安全、有效治疗方法。

[Estimating HIV incidence among female sex workers and injection drug users in Dehong Prefecture, 2009-2017]

Objective: To obtain HIV incidence among injection drug users (IDU) and female sex workers (FSW) in Dehong Prefecture, Yunnan Province during 2009-2017. Methods: We recruited drug users and female sex workers from all sentinel surveillance sites across Dehong Prefecture during 2009-2017. A total of 10 480 IDU and 18 126 FSW in Dehong Prefecture were recruited by fingerprint technique. Data about drug uses, commercial sexual behavior, sociodemographic characteristics was collected by structured questionnaire. HIV-positive patients who were long-term infected or with CD4(+) T cell count was ≤200 were not included for further HIV incidence testing. Also, those who self-identified as on antiretroviral treatment (ART) or AIDS cases were also excluded. A total of 841 and 157 plasma specimens from IDU and FSW that met the inclusion criterion were finally included, respectively. Limiting antigen avidity enzyme immunoassay(LAg-Avidity EIA) were performed to calculate the HIV incidence among these two sub-populations. Results: A total of 3 444 IDU were HIV-positive, among which 884 (25.7%) were Burmese with age of (30.4±7.7), and 2 560 were Chinese with age of (36.6±7.3). Among 228 HIV-positive FSW, 109 (47.8%) were Burmese with age of (27.1±6.3), 119 (52.5%) were Chinese with age of (29.9±11.1). For IDU, the estimated HIV incidence among Burmese in 2009-2010, 2011-2012, 2013-2014, 2015-2017 was 4.20% (95%CI: -0.55%-8.95%), 7.75% (95%CI: 2.95%-12.55%), 11.79% (95%CI: 5.38%-18.20%), 10.30% (95%CI: 5.67%-14.94%), respectively, while Chinese were 3.11% (95%CI: 1.59%-4.64%), 0.03% (95%CI: -0.03%-0.08%), 1.55% (95%CI: 0.54%-2.57%), 0.58% (95%CI: -0.06%-1.04%), respectively. In 2009-2011, 2012-2014, 2015-2017, estimated HIV incidence among Burmese FSW was 0.22% (95%CI: -0.21%-0.64%), 1.24%(95%CI: 0.15%-2.32%), 0.55%(95%CI: 0.01%-1.08%). Whereas, estimated HIV incidence among Chinese FSW was 0.62% (95%CI: 0.25%-0.98%), 0.11% (95%CI: -0.04%-0.26%), 0.22% (95%CI: 0-0.44%). Conclusion: HIV incidences among Chinese IDU and FSW are on the downward trend, while Burmese IDU and FSW seem to be gaining momentum.

[Experiment research of natural killer cells amplification in vitro and the killing effect on ovarian cancer cells]

Objective: To amplify natural killer (NK) cells in vitro and explore its killing effect on ovarian cancer cells. Methods: (1) The separation of NK cells and identification. A total of 20 ml peripheral blood of one healthy volunteer was collected in Nov. 2015, Peking University People's Hospital. The peripheral blood mononuclear cells of normal volunteers were isolated, cultured in vitro and amplificated cultivation for 14 days with K562 cells transfected and expressing interleukin 21 (IL-21-K562) as nourish cells. The number and dynamic state of the growth cells were monitored during the cultured process. Cells were harvested and counted after 14 days cultured. The NK cells phenotypes were detected by flow cytometry. (2) The killing effect of NK cells on ovarian cancer cells: the ratio of effector cells (NK cells) and target cells (ovarian cancer cells and its control) was 50∶1, 20∶1, 10∶1, 5∶1 or 1∶1, NK cells killing effect on ovarian cancer cells was detected by the lactate dehydrogenase (LDH) release experiments. Results: (1) The results of NK cells establishment and phenotypic characterization: the cells were induced in vitro for 14 days by amplification culture. With the extension of incubation time, the number of NK cells increased constantly, from 2.0×10(7) on day 0 to 5.1×10(9) on day 14. Obvious amplification of the total number of cells were detected for 255 times. Living cells unstained by trypan blue eventually reached 95% above. Before and after the induction and amplification in vitro, the percentage of NK cells(CD(3)(-)CD(5)(6+)cells) in CD(3)- cells were 2.33% and 85.32%, respectively (P<0.01), which covered the whole lymphocytes 1.06% and 69.42%, respectively (P<0.01), which showed that NK was the main cell type in the amplificated lymphocytes. (2) The killing rate of NK cells on ovarian cancer cells in vitro: the results detected by LDH release experiments showed that NK cells could performed strong nonspecific killing effect on ovarian cancer cell lines SKOV3, HOC1A, 3AO and CAOV3, as well the normal ovarian cell line T29 and NK sensitive cell line K562, and the killing effect increased significantly along with the increase of effector cells and target cells ratio (P<0.01). When the ratio was 1∶1, the killing rate was 37% for K562, while the rate of killing of other cells was around 10% (P<0.05). When the effect-target ratio was 20∶1 and 50∶1, in addition to CAOV3 cells (more than 70%), NK cells had a kill rate of more than 80% for other ovarian cancer cells lines and their control cell K562 and T29 cells (P>0.05). Conclusion: NK cells could be established in vitro and have a good non-specific killing effect on ovarian cancer cells.

Synergism between RIZ1 gene therapy and paclitaxel in SiHa cervical cancer cells

RIZ1 is a tumor suppressor gene. The purpose of the present study was to investigate the inhibitory effect of RIZ1 gene therapy on the growth of SiHa cervical cancer cells and its synergism with paclitaxel. The expression levels of RIZ1 were examined by real-time PCR and western blotting before and after transfection of RIZ1. The effects of paclitaxel or pcDNA3.1(+)-RIZ1 alone or in combination, on the proliferation of SiHa cells were evaluated by MTT method. The inhibitory effect on the proliferation of SiHa cells was more significant in the pcDNA3.1(+)-RIZ1 combined with paclitaxel group than in the pcDNA3.1(+)-RIZ1 or paclitaxel groups (P<0.05). The expression level of RIZ1 in SiHa cells increased after treatment with paclitaxel, which indicated a synergism between them. RIZ1 gene therapy combined with paclitaxel showed stronger cell inhibition than paclitaxel alone, which indicated a synergism between them.

Combined Anti-CD154/CTLA4Ig Costimulation Blockade-Based Therapy Induces Donor-Specific Tolerance to Vascularized Osteomyocutaneous Allografts

Tolerance induction by means of costimulation blockade has been successfully applied in solid organ transplantation; however, its efficacy in vascularized composite allotransplantation, containing a vascularized bone marrow component and thus a constant source of donor-derived stem cells, remains poorly explored. In this study, osteomyocutaneous allografts (alloOMCs) from Balb/c (H2(d) ) mice were transplanted into C57BL/6 (H2(b) ) recipients. Immunosuppression consisted of 1 mg anti-CD154 on day 0, 0.5 mg CTLA4Ig on day 2 and rapamycin (RPM; 3 mg/kg per day from days 0-7, then every other day for 3 weeks). Long-term allograft survival, donor-specific tolerance and donor-recipient cell trafficking were evaluated. Treatment with costimulation blockade plus RPM resulted in long-term graft survival (>120 days) of alloOMC in 12 of 15 recipients compared with untreated controls (median survival time [MST] ≈10.2 ± 0.8 days), RPM alone (MST ≈33 ± 5.5 days) and costimulation blockade alone (MST ≈45.8 ± 7.1 days). Donor-specific hyporesponsiveness in recipients with viable grafts was demonstrated in vitro. Evidence of donor-specific tolerance was further assessed in vivo by secondary donor-specific skin graft survival and third-party graft rejection. A significant increase of Foxp3(+) regulatory T cells was evident in tolerant animals. Donor cells populated peripheral blood, thymus, and both donor and recipient bone marrow. Consequently, combined anti-CD154/CTLA4Ig costimulation blockade-based therapy induces donor-specific tolerance in a stringent murine alloOMC transplant model.

Progress on Post Traumatic Epilepsy and Its Forensic Evaluation

Post traumatic epilepsy （PTE） refers to the epileptic seizures after traumatic brain injury. Organic damage can be found by imaging examination, and abnormal electroencephalogram can be detected via electroencephalogram examination which has the similar location of the brain injury. PTE has the characteristics of low incidence, absence of case reports, and easy to exaggerate the state of illness, which add difficulties to the forensic identification. This paper reviews the status of epidemiology, pathogenesis, clinical treatment and forensic identification for PTE.

Four-wave mixing and octave-spanning supercontinuum generation in a small core hydrogenated amorphous silicon fiber pumped in the mid-infrared

An octave-spanning supercontinuum is generated in a hydrogenated amorphous silicon core fiber when pumped in the mid-infrared regime. The broadband wavelength conversion which extends from the edge of the telecommunications band into the mid-infrared (1.64-3.37 μm) is generated by four-wave mixing (FWM) and subsequent pulse break-up, facilitated by the high material nonlinear figure of merit and the anomalous dispersion of the relatively small 1.7 μm diameter core fiber. The FWM sidebands and corresponding supercontinuum can be tuned through the pump parameters, and show good agreement with the predicted phase-matching curves for the fiber.

The role of HE4 in ovarian cancer: inhibiting tumour cell proliferation and metastasis

As a promising biomarker, human epididymis protein 4 (HE4) has been widely used for the early detection and differential diagnosis of ovarian cancer. This study evaluated the function of HE4 in the carcinogenesis and progression of ovarian cancer. An enzyme immunometric assay, used to detect HE4 in the serum of ovarian cancer patients, showed that the protein could discriminate between malignant and benign ovarian tumours with high specificity. An exogenous HE4 gene was transfected into ovarian cancer cell lines and an immortalized ovarian epithelial cell line. Compared with the controls, HE4 overexpression significantly promoted cell apoptosis and adhesion. Overexpression of HE4 also led to significant inhibition of cell proliferation, migration and invasiveness in vitro, as well as xenograft tumour formation in vivo. This is the first report to demonstrate the functional importance of HE4 in multiple cellular processes and indicates that HE4 may play a protective role in the progression of ovarian cancer.

Expression of beclin 1, an autophagy-related protein, in human cervical carcinoma and its clinical significance

PURPOSE

To investigate the impact of beclin 1 on prognosis of cervical cancer, we determined the expression of beclin 1 in cervical cancer, cervical intraepithelial neoplasia (CIN) and normal cervical tissues.

METHODS

A total of 122 cases of cervical cancer, 35 cases with CIN and 31 cases with uterine fibroids were collected at the Cancer Center of Sun Yat University to determine the expression of beclin 1.

RESULTS

Beclin 1 positive rate in normal cervical tissues, CIN tissues and cervical cancers was 83.9%, 74.3% and 53.3%, respectively, and it was significantly different between the three groups (p < 0.01). Beclin 1 expression was negatively correlated with cervical cancer differentiation, lymph node metastasis, recurrence and death (p < 0.05). The negative expression is the risk factor affecting overall survival (p < 0.05) and progression-free survival (PFS) (p < 0.05). Multivariate analysis showed that beclin 1 negative expression was an independent risk factor of PFS time.

CONCLUSIONS

Beclin 1 may play a role in the occurrence and development of cervical cancer. Beclin 1 positive expression in patients indicates a better prognosis.

DNA methylation of the RIZ1 tumor suppressor gene plays an important role in the tumorigenesis of cervical cancer

Abtract

Regulation of blood and vascular cell function by bioactive lysophospholipids

Lysophosphatidic acid (LPA), its sphingolipid homolog sphingosine 1-phosphate (S1P) and several other related molecules constitute a family of bioactive lipid phosphoric acids that function as receptor-active mediators with roles in cell growth, differentiation, inflammation, immunomodulation, apoptosis and development. LPA and S1P are present in physiologically relevant concentrations in the circulation. In isolated cell culture systems or animal models, these lipids exert a range of effects that suggest that S1P and LPA could play important roles in maintaining normal vascular homeostasis and in vascular injury responses. LPA and S1P act on a series of G protein-coupled receptors, and LPA may also be an endogenous regulator of PPARgamma activity. In this review, we discuss potential roles for lysolipid signaling in the vasculature and mechanisms by which these bioactive lipids could contribute to cardiovascular disease.

Photo-luminescent hydroxyapatite coatings through a bio-mimetic process

Hydroxyapatite (HAp) is the major inorganic component in natural bones. Because HAp has the advantages of excellent biocompatibility, free of cell toxicity, and forming strong bonding to bone osteoinductively, it has been widely studied and prepared in many forms for orthopedic and dental applications. In the recent years, silicon based bio-chip was extensively studied. To improve the biocompatibility and search for novel application of bio-chip are not only an important aim but also a challenge. In the previous literatures, it's reported that HAp is relatively difficult to be coated onto a Si(1 0 0) substrate. In this study, we successfully manufactured crystalline HAp on to Si(1 0 0) using simplified supersaturated solution and investigated the structural characteristics through the measurements of XRD, FTIR, FE-SEM, and XPS. The photo-luminescent properties of the coatings were also studied.

Liver CT-image retrieval based on Gabor texture

Gabor schemes of image representation have shown great success in many texture related computer vision applications. This is mainly because the primitives of image representation in vision have a wavelet form similar to Gabor elementary functions (GEF's). We use Gabor approach to analyze the texture of liver CT-images and extract the corresponding feature vectors. Then, the feature vectors are used to facilitate content-based image retrieval (CBIR). In experiments, a batch of liver CT images containing several types of CT findings is collected, and retrieval results by Gabor texture are present.

Spermatozoan morphology of four species of bivalve (Heterodonta, Veneridae) from Taiwan

Using transmission and scanning electron microscopy, the mature spermatozoa of four bivalves of the family Veneridae--Gafrarium tumidum and Circe scripta (Circinae), Pitar sulfureum (Pitarinae) and Gomphina aequilatera (Tapetinae)--are described for the first time and compared with those of other bivalves, particularly other heterodonts. As our observations show, the spermatozoa of these four species are of the primitive type or ect-aquasperm form. The head contains a slightly curved nucleus with a short cone-shaped acrosome. The structure of the acrosome is typical of heterodont bivalves and two major components of the acrosomal vesicle material can be distinguished. The midpiece exhibits four or five mitochondria which surround the proximal and the distal centrioles. Variation in the shape and dimensions of the acrosomal vesicle and nucleus is substantial in these four Veneroidea species.

Toxicity of different industrial effluents in Taiwan: a comparison of the sensitivity of Daphnia similis and Microtox

Industrial effluents are known to exhibit toxicity toward different aquatic organisms. In Taiwan management of these discharges still relies on chemical and physical and physical characteristics of water, although various standard method for assessing aquatic toxicity have been proposed by the Taiwan Environmental Protection Administration. In this study we examined the toxicity and compared the sensitivity of different types of industrial effluents using two proposed toxicity tests: the Daphnia similis acute toxicity test and the Microtox acute assay (Vibrio fischeri). Results showed that electroplating effluents were the most toxic of all the effluents tested, followed by acrylonitrile manufacturing, pulp/paper, and tannery effluents. The EC50 of an electroplating effluent for D. similis and V. fischeri (15 min) was as low as, respectively, 2.9% and 3.9% of the whole effluent. The other effluents were not acutely toxic to either organism tested. However, the tests exhibited different sensitivity toward various discharges. Only the electroplating and acrylonitrile manufacturing effluents had effects on both organisms. These results indicate the importance of the incorporation of aquatic toxicity tests into the management scheme for treated wastewaters.

Calcium-regulated DNA binding and oligomerization of the neuronal calcium-sensing protein, calsenilin/DREAM/KChIP3

Calsenilin/DREAM/KChIP3, a member of the recoverin branch of the EF-hand superfamily, interacts with presenilins, serves as a calcium-regulated transcriptional repressor, and interacts with A-type potassium channels. Here we report physicochemical characterization of calcium binding, oligomerization, and DNA binding of human calsenilin/DREAM/KChIP3. Equilibrium Ca(2+) binding measurements indicate that the protein binds 3 Ca(2+) with a dissociation constant of 14 microM and a Hill coefficient of 0.7. Dynamic light scattering and size exclusion chromatography show that the Ca(2+)-bound protein exists as a dimer at protein concentrations lower than 150 microM and forms a tetramer at concentrations above 200 microM. The Ca(2+)-free protein is a tetramer in the concentration range 20-450 microM. Isothermal titration calorimetry and dynamic light scattering indicate that the Ca(2+)-free protein tetramer binds endothermically (DeltaH = +25 kcal/mol) to four molecules of DNA derived from the downstream regulatory element (DRE) of either the prodynorphin or c-fos genes. One DRE molecule binds tightly to the protein with a dissociation constant (K(d)) of 75 nM, and the other three bind more weakly (K(d) = 640 nM). No significant DNA binding was observed for the Ca(2+)-bound protein. The N-terminal protein fragment (residues 1-70) binds nonspecifically to DRE in a Ca(2+)-independent manner, whereas a C-terminal fragment containing the four EF-hands (residues 65-256) binds DRE (K(d) = 200 nM) in a Ca(2+)-regulated and sequence-specific fashion. The C-terminal fragment is a tetramer in the Ca(2+)-free state and dissociates into dimers at saturating Ca(2+) levels.

A point mutation in the N-terminal coiled-coil domain releases c-Fes tyrosine kinase activity and survival signaling in myeloid leukemia cells

The c-fes locus encodes a 93-kDa non-receptor protein tyrosine kinase (Fes) that regulates the growth and differentiation of hematopoietic and vascular endothelial cells. Unique to Fes is a long N-terminal sequence with two regions of strong homology to coiled-coil oligomerization domains. We introduced leucine-to-proline substitutions into the coiled coils that were predicted to disrupt the coiled-coil structure. The resulting mutant proteins, together with wild-type Fes, were fused to green fluorescent protein and expressed in Rat-2 fibroblasts. We observed that a point mutation in the first coiled-coil domain (L145P) dramatically increased Fes tyrosine kinase and transforming activities in this cell type. In contrast, a similar point mutation in the second coiled-coil motif (L334P) was without effect. However, combining the L334P and L145P mutations reduced transforming and kinase activities by approximately 50% relative to the levels of activity produced with the L145P mutation alone. To study the effects of the coiled-coil mutations in a biologically relevant context, we expressed the mutant proteins in the granulocyte-macrophage colony-stimulating factor (GM-CSF)-dependent myeloid leukemia cell line TF-1. In this cellular context, the L145P mutation induced GM-CSF independence, cell attachment, and spreading. These effects correlated with a marked increase in L145P protein autophosphorylation relative to that of wild-type Fes. In contrast, the double coiled-coil mutant protein showed greatly reduced kinase and biological activities in TF-1 cells. These data are consistent with a role for the first coiled coil in the negative regulation of kinase activity and a requirement for the second coiled coil in either oligomerization or recruitment of signaling partners. Gel filtration experiments showed that the unique N-terminal region interconverts between monomeric and oligomeric forms. Single point mutations favored oligomerization, while the double point mutant protein eluted essentially as the monomer. These data provide new evidence for coiled-coil-mediated regulation of c-Fes tyrosine kinase activity and signaling, a mechanism unique among tyrosine kinases.

Azepanone-based inhibitors of human and rat cathepsin K

The synthesis, in vitro activities, and pharmacokinetics of a series of azepanone-based inhibitors of the cysteine protease cathepsin K (EC 3.4.22.38) are described. These compounds show improved configurational stability of the C-4 diastereomeric center relative to the previously published five- and six-membered ring ketone-based inhibitor series. Studies in this series have led to the identification of 20, a potent, selective inhibitor of human cathepsin K (K(i) = 0.16 nM) as well as 24, a potent inhibitor of both human (K(i) = 0.0048 nM) and rat (K(i,app) = 4.8 nM) cathepsin K. Small-molecule X-ray crystallographic analysis of 20 established the C-4 S stereochemistry as being critical for potent inhibition and that unbound 20 adopted the expected equatorial conformation for the C-4 substituent. Molecular modeling studies predicted the higher energy axial orientation at C-4 of 20 when bound within the active site of cathepsin K, a feature subsequently confirmed by X-ray crystallography. Pharmacokinetic studies in the rat show 20 to be 42% orally bioavailable. Comparison of the transport of the cyclic and acyclic analogues through CaCo-2 cells suggests that oral bioavailability of the acyclic derivatives is limited by a P-glycoprotein-mediated efflux mechanism. It is concluded that the introduction of a conformational constraint has served the dual purpose of increasing inhibitor potency by locking in a bioactive conformation as well as locking out available conformations which may serve as substrates for enzyme systems that limit oral bioavailability.

Essential role of the mitochondrial apoptosis-inducing factor in programmed cell death

Programmed cell death is a fundamental requirement for embryogenesis, organ metamorphosis and tissue homeostasis. In mammals, release of mitochondrial cytochrome c leads to the cytosolic assembly of the apoptosome-a caspase activation complex involving Apaf1 and caspase-9 that induces hallmarks of apoptosis. There are, however, mitochondrially regulated cell death pathways that are independent of Apaf1/caspase-9. We have previously cloned a molecule associated with programmed cell death called apoptosis-inducing factor (AIF). Like cytochrome c, AIF is localized to mitochondria and released in response to death stimuli. Here we show that genetic inactivation of AIF renders embryonic stem cells resistant to cell death after serum deprivation. Moreover, AIF is essential for programmed cell death during cavitation of embryoid bodies-the very first wave of cell death indispensable for mouse morphogenesis. AIF-dependent cell death displays structural features of apoptosis, and can be genetically uncoupled from Apaf1 and caspase-9 expression. Our data provide genetic evidence for a caspase-independent pathway of programmed cell death that controls early morphogenesis.

Src homology 2 domain substitution modulates the kinase and transforming activities of the Fes protein-tyrosine kinase

The c-fes proto-oncogene encodes a Mr 93,000 protein-tyrosine kinase (Fes) that is strongly expressed in myeloid cells and has been implicated in myelomonocytic differentiation. Fes autophosphorylation and transforming activity are highly restrained after ectopic expression in fibroblasts, indicating tight negative regulation of Fes kinase activity in vivo. Here we investigated the regulatory role of the Fes Src homology 2 (SH2) domain by producing a series of chimeric constructs in which the Fes SH2 domain was replaced with those of the transforming oncogenes v-Fps and v-Src or by the NH2-terminal SH2 domain of the Ras GTPase-activating protein. Wild-type and chimeric Fes proteins readily underwent tyrosine autophosphorylation in vitro and produced identical cyanogen bromide phosphopeptide cleavage patterns, indicating that the SH2 substitutions did not influence overall kinase activity or autophosphorylation site selection. However, metabolic labeling of Rat-2 fibroblasts expressing each construct showed that only the Fes/Src SH2 chimera was active in vivo. Consistent with this result, the Fes/Src SH2 domain chimera exhibited potent transforming activity in fibroblasts and enhanced differentiation-inducing activity in K-562 myeloid leukemia cells. In addition, the Fes/Src SH2 chimera exhibited constitutive localization to focal adhesions in Rat-2 fibroblasts and induced the attachment and spreading of TF-1 myeloid cells. These data demonstrate a central role for the SH2 domain in the regulation of Fes kinase activity and biological function in vivo.

A thin glycoprotein coating of a synthetic lenticule does not cause nutritional deficiency of the anterior cornea

PURPOSE

This study investigated whether a glycoprotein coating that will be used to enhance corneal epithelialization affects in situ nutritional passage through a permeable membrane.

METHODS

Sixteen adult cats were equally divided into two groups. Polycarbonate membranes with pore size of 0.1 microm and total pore area (porosity) of 3.1% were used as implant materials. The membranes for Group 1 were coated with a thin layer of Collagen I, while the membranes for Group 2 were uncoated. Each membrane with 8-mm diameter was implanted into an interlamellar pocket of the cornea. The eyes were observed for approximately 35 days to monitor clinical signs of nutritional deficiency of the cornea, and then 7 membranes were removed from the eyes. The permeability of the explanted membranes to glucose, inulin and albumin was used to predict the in situ difference between the coated and uncoated groups in regard to nutritional passage through the membranes. To investigate the long-term effect of the surface coating on corneal health, two animals from Group 1 were followed for up to two years and then both eyes of each animal underwent histological examination.

RESULTS

Clinically, no post-surgical complications associated with nutritional deficiency were observed in any of the eyes. Nutritional permeability tests showed no significant differences between the coated and uncoated membranes. Histologically, the long-term animals showed no abnormal morphology associated with nutritional deficiency in the cornea anterior or posterior to the membranes.

CONCLUSIONS

A thin glycoprotein coating on a permeable membrane does not appear to affect the nutritional supply of the anterior cornea and therefore can be used to enhance epithelialization of synthetic corneal onlays in vivo.

Rilmenidine reveals differences in the pharmacological characteristics of prejunctional alpha2-adrenoceptors in the guinea-pig, rat and pig

1. The alpha2A and alpha2D-adrenoceptor subtypes are thought to be species homologs most easily differentiated on the basis of the potency of antagonists. In the present study we have compared the effect of rilmenidine with two other selective alpha2-adrenoceptor agonists, UK-14304 (5-bromo-6- [2-imidazolin-2-ylamino]-quinoxaline) and clonidine, against electrically-evoked contractions in five isolated preparations from the rat, guinea-pig and pig, and, where possible, determined the receptor subtype involved. 2. UK-14034, clonidine and rilmenidine produced concentration-dependent inhibition of the electrically-evoked contractions of the rat isolated vas deferens and tail artery and the guinea-pig ileum. These inhibitory effects were reversed by the selective alpha2-adrenoceptor antagonist, RX-811058 (1 microM), except in the rat tail artery preparations where the remaining neurogenic response was inhibited; evidence for the involvement of 'innervated' alpha2-adrenoceptors. Both clonidine and UK-14304 produced concentration-dependent inhibition of responses in the porcine isolated tail artery and urinary bladder but clonidine was markedly less efficacious in these preparations. In contrast, rilmenidine failed to inhibit the neurogenic contractions in either preparation. 3. Although rilmenidine failed to elicit a detectable response in either the porcine isolated tail artery or urinary bladder, it (10 microM and 30 microM, respectively) competitively antagonised the inhibitory effects of UK-14304 with an estimated dissociation constant of (pK(B)) 5.82 and 5.93, respectively. 4. Prazosin (1 microM) failed to alter the effect of UK-14304 against neurogenic contractions in the porcine isolated urinary bladder, while rauwolscine (pK(B) 8.87) was 10 fold more potent than phentolamine (pK(B) 7.56). On the other hand, phentolamine (pK(B) 8.42) was only marginally more potent than rauwolscine (pK 8.05) against clonidine-induced inhibition of electrically-evoked contractions of the guinea-pig isolated ileum. This pharmacological evidence with antagonists supports the presence of alpha2D-adrenoceptors in the rat and guinea-pig and the alpha2A-adrenoceptors in the pig. 5. We have demonstrated that rilmenidine, unlike clonidine and UK-14304, is devoid of any agonist activity at prejunctional alpha2A-adrenoceptors in the pig, but is an efficacious agonist at alpha2D-adrenoceptors in the rat and guinea-pig.

Bilateral femoral neuropathy after vaginal hysterectomy

A case of bilateral femoral neuropathy as a complication of vaginal hysterectomy is presented. A 45-year-old woman developed weakness of both quadriceps, absence of bilateral knee jerks, and numbness over bilateral anteromedial thighs and medial lower legs after a vaginal hysterectomy. Electromyographic examination revealed evidence of denervation in the bilateral quadriceps. A nerve conduction study showed prolonged distal latencies and markedly reduced amplitude of the compound muscle action potentials in bilateral femoral nerves. It is suggested that this complication is caused by a microvascular and/or local mechanical injury of the femoral nerve, which is compressed beneath the tough inguinal ligament in a sustained posture with the hip joint in an extreme abduction and external rotation position. The prognosis was excellent with almost complete recovery within 10 weeks. The complication may be preventable by minimizing operating time, changing the patient's posture, and limiting the degree of flexion, abduction, and external rotation of the hip.

Comparison of metoprolol and carvedilol pharmacology and cardioprotection in rabbit ischemia and reperfusion model

Carvedilol, a selective alpha1 and non-selective beta-adrenoceptor antagonist and antioxidant, has been shown to provide significant cardiac protection in animal models of myocardial ischemia. To further explore the mechanisms contributing to carvedilol cardioprotection efficacy, the effects of carvedilol on hemodynamic variables, infarct size and myeloperoxidase activity (an index of neutrophil accumulation) were compared with a beta1-selective adrenoceptor antagonist, metoprolol. Carvedilol (1 mg/kg) or metoprolol (1 mg/kg or 1 mg/kg + 0.5 mg/kg 90 min later) was given intravenously 5 min before reperfusion. In vehicle-treated rabbits, ischemia (60 min) and reperfusion (180 min) resulted in significant increments in left ventricular end diastolic pressure, large infarcts (59+/-2.6% of area-at-risk) and marked increase in myeloperoxidase activity (0.59+/-0.09 U/100 mg tissue). Carvedilol treatment resulted in sustained reduction of pressure-rate-index and significantly smaller infarcts (22.0+/-2.5%, P < 0.01 vs. vehicle) as well as decreased myeloperoxidase activity (0.186+/-0.056 U/100 mg tissue, P < 0.01 vs. vehicle). The highest dose of metoprolol, 1 mg/kg + 0.5 mg/kg, that resulted in pressure-rate-index comparable to that of 1.0 mg/kg carvedilol, failed to reduce myeloperoxidase activity in the ischemic myocardial tissue, and the infarct size (35+/-3.1%) was significantly larger than in carvedilol-treated animals. Taken together, this study suggests that the superior cardioprotection of carvedilol over metoprolol is not a consequence of hemodynamic variances but possibly the result of the additional pharmacological properties of carvedilol such as the antioxidant and anti-neutrophil effects.

Nutritional requirements of the corneal epithelium and anterior stroma: clinical findings

PURPOSE

To monitor the health of the epithelium and the anterior stroma when porous membranes are implanted into the feline cornea and to determine membrane diffusivity characteristics needed to maintain corneal integrity.

METHODS

Filtration membranes in a range of effective pore sizes of less than 15 nm (groups 1 and 2, n = 11), 25 nm (group 3, n = 8), 50 nm (group 4, n = 16), and 100 nm (group 5, n = 15) were implanted into an interlamellar corneal pocket of the stroma. The implanted membranes ranged in thickness from 6 nm to 15 nm and were between 8 mm and 12 mm in diameter. Animals were monitored for clinical signs of intolerance to the implants.

RESULTS

At 1 month, thinning and ulceration had occurred in the epithelium and the anterior stroma of all animals in groups 1 and 2; epithelial changes, anterior stromal thinning, and ulceration had developed in 75% of animals of group 3; 50% of animals showed vascularization and only 7% showed epithelial degeneration in group 4; and local anterior stromal thinning was observed in 7% of animals in group 5, indicating clinical acceptance of the implanted membrane. In the long term (greater than 50 days), 30% and 73% of the group 4 and 5 corneas, respectively, were clinically quiet. Analysis of the failure times indicated an inverse relation between failure rate and pore size: less than 15 nm > 25 nm > 50 nm > 100 nm. The difference between the 100-nm and 50-nm membranes was significant (P = 0.03).

CONCLUSIONS

A corneal implant must have a porosity greater than that provided by 50-nm membranes. The 100-nm membranes used in this study establish the porosity needed to satisfy the nutritional requirements of the cornea.

Carvedilol-liposome interaction: evidence for strong association with the hydrophobic region of the lipid bilayers

Carvedilol (Kredex, Coreg) is a multiple action antihypertensive drug that has been shown to protect cell membranes from lipid peroxidative damages. In this study the physical and structural effects of carvedilol on lipid bilayers are investigated by fluorescence techniques, differential scanning calorimetry and other physical methods. Carvedilol binds to liposomal membranes (9:1 DMPC:DMPG) strongly with an apparent binding constant on the order of 10(4) M-1 in PBS (pH 7.4). The characteristic changes in its intrinsic fluorescence properties when bound to liposomes suggest that this compound is situated in a non-polar environment. The Stern-Volmer and bimolecular quenching constants, determined using nitrate as the fluorescence quencher, for the free and bound carvedilol indicate that the carbazole moiety is at a depth of > 11 A in the lipid bilayer. Fluorescence anisotropy measurements show that, unlike the membrane probes DPH and TMA-DPH, carvedilol is relatively mobile, and does not have a rigidly-defined molecular orientation in the bilayers. Differential scanning calorimetry results indicate that carvedilol is an effective membrane "fluidizer' as it dose-dependently lowers the gel to liquid crystalline transition temperature and broadens the endothermic transition. Comparative studies of interactions of carbazole, 4-OH carbazole and carvedilol with the model liposomal membranes reveal a possible role of membrane-partitioning in their antioxidant efficacy. These findings are discussed in perspective with the membrane biophysical properties of different classes of therapeutic significant lipid antioxidants in mind.

The chemistry of pseudomonic acid. 17. Dual-action C-1 oxazole derivatives of pseudomonic acid having an extended spectrum of antibacterial activity

A series of C-1 oxazole isosteres of pseudomonic acid A (mupirocin) bearing a nitroheterocycle have been synthesized, and significant differences in both spectrum of activity and potency were found between these derivatives and mupirocin. Additionally, the antibacterial potency of two members of this class of compounds against mupirocin-resistant staphylococci could not be accounted for solely by inhibition of the target enzyme isoleucyl-tRNA synthetase (IRS), indicating an additional mode of action. The most potent compound, the nitrofuran 3f (SB 205952), was the most electron affinic derivative prepared and was transformed by NAD(P)H-dependent bacterial reductases at a rate similar to that for nitrofurantoin. The second mode of action of this compound may therefore arise from its reduction to a species with cellular targets other than IRS. In in vivo studies, 3f was shown to be a very effective agent by both the subcutaneous and oral routes of administration.

Structural study of electrolysis-induced degradation of the growth hormone releasing peptide His-D-Trp-Ala-Trp-D-Phe-Lys-NH2

Growth hormone releasing peptide (GHRP, sequence His-D-Trp-Ala-Trp-D-Phe-Lys-NH2) is a synthetic hexapeptide under consideration for transdermal iontophoretic drug delivery. Cyclic voltammetry, controlled-potential electrolysis, HPLC/UV analysis, LC/MS/MS analysis, and EPR spin-trapping studies indicate that the electrolysis-induced oxidative degradation of GHRP is likely to be mediated by electrogenerated oxygen radicals from the electrolysis of water. Within 2 h and up to 2.5 V versus an Ag/AgCl reference electrode, the peptide backbone remains largely intact. The chemical modifications are selectively on imidazole (histidine) and indole (tryptophan). Strategies for alleviating the electrolysis-induced degradation of GHRP are proposed.

Basal and stimulated platelet calcium and sodium in hypertensive versus normotensive black people

To examine further the potential role of intracellular cations in hypertension a nested case-control study was carried out in conjunction with a population-based survey. Based on a house-to-house sampling scheme, 43 hypertensive and 56 normotensive black residents of Maywood, IL, were recruited. Free cytosolic calcium (Cai) and intracellular stores of calcium after stimulation with ionomycin were determined in platelets with the fluoroprobe Indo-I; intracellular sodium (Nai) measured at rest and after incubation with ouabain was estimated with SBFI. Cell sodium content was also assayed in erythrocytes. Resting Cai and Nai were not different in hypertensives compared with normotensives, although ionomycin-stimulated levels of Cai were correlated with systolic blood pressure (r = 0.3; P = 0.04). A consistent set of inter-relations among the various cation parameters was observed, lending support to the hypothesis that the cellular metabolism of sodium and calcium may be linked in the pathophysiological pathway to hypertension.