Spontaneous conus infarction with "snake-eye appearance" on magnetic resonance imaging: A case report and literature review.

BACKGROUND: Infarction of the conus medullaris is a rare form of spinal cord infarction. The first symptom is usually acute non-characteristic lumbar pain, followed by lower limb pain, saddle numbness, fecal incontinence, and sexual dysfunction. Spontaneous conus infarction with "snake-eye appearance" on magnetic resonance imaging has rarely been reported. CASE SUMMARY: We report a 79-year-old male patient with spontaneous conus infarction who had acute lower extremity pain and dysuria as the first symptoms. He did not have any recent history of aortic surgery and trauma. Magnetic resonance imaging revealed a rare "snake-eye appearance." In addition, we reviewed the literature on 23 similar cases and summarized the clinical features and magnetic resonance manifestations of common diseases related to the "snake-eye sign" to explore the etiology, imaging findings, and prognosis of spontaneous conus infarction. CONCLUSION: We conclude that acute onset of conus medullaris syndrome combined with "snake-eye appearance" should be strongly suspected as conus medullaris infarction caused by anterior spinal artery ischemia. This special imaging manifestation is helpful in the early diagnosis and treatment of conus infarction.

Cofactor-Free Dioxygenases-Catalyzed Reaction Pathway via Proton-Coupled Electron Transfer.

Understanding the general mechanism of the metal-free and cofactor-free oxidases and oxygenases catalyzed activation of triplet O2 is one of the most challenging questions in the field of enzymatic catalysis. Herein, we have performed Quantum Mechanics/Molecular Mechanics (QM/MM) multiscale simulations to reveal the detailed mechanism of the HOD catalyzed (i.e., 1-H-3-hydroxy-4-oxoquinaldine 2,4-dioxygenase from Arthrobacter nitroguajacolicus Rü61a) decomposition of N-heteroaromatic compounds. The complete catalytic mechanism includes four steps: (1) proton transfer from 1-H-3-hydroxy-4-oxoquinaldine (QND) substrate to His251 residue coupled with an electron transfer from QND to triplet O2 (i.e., PCET), (2) formation of C-O bond via an open-shell singlet diradical recombination pathway, (3) ring-closure to form a bicyclic ring, and (4) dissociation of CO. The dissociation of CO is determined as the rate-limiting step, and its calculated energy barrier of 14.9 kcal/mol is consistent with the 15.5 kcal/mol barrier derived from experimental kinetic data. The mechanistic profile is not only valuable for understanding the fundamental pathway of cofactor-free oxidases and oxygenases-catalyzed reactions involving the triplet O2 activation but also discloses a new pathway that undergoes the processes of PCET and open-shell singlet transition state.

Evaluation of visual inspection as the primary screening method in a four-year cervical (pre-) cancer screening program in rural China.

The aim of the study is to evaluate the feasibility of visual inspection with acetic acid/Lugol's iodine (VIA/VILI) as a primary screening method for cervical lesions in low-resource settings in China. Participants underwent VIA/VILI, and, if positive, received colposcopy and direct biopsy of visible lesions. Women who were negative for VIA/VILI or who were diagnosed with cervical intraepithelial neoplasia (CIN) 1 were re-screened the following year with the same procedure. In total, 10,269 women received VIA/VILI (of whom 8263, twice). Overall test positivity was 8.07% (1495/18532) for VIA/VILI, 33.44% (500/1495) for colposcopy, and the incidence of pathology-confirmed CIN1, CIN2/3 and cervical cancer was 0.85% (87/10,269), 0.53% (54/10,269) and 0.02% (2/10,269), respectively. Women aged 30-39 years at screening had higher rates of CIN2+ (include CIN2, CIN3 and cervical cancer). Our study indicates that VIA/VILI is a simple, feasible, and effective primary cervical cancer screening method in an impoverished, rural community that lacks access to standard medical care.

Analysis of the effectiveness of visual inspection with acetic acid/Lugol's iodine in one-time and annual follow-up screening in rural China.

PURPOSE: Via a large population-based survey conducted in rural, southwestern China, we aim to evaluate the effect of visual inspection with acetic acid/Lugol's iodine (VIA/VILI) on diagnosing cases of cervical cancer and of pre-cancerous lesions while exploring the mode of cervical prevention and control in low-resource settings in China. METHODS: Women aged 30-59 years from Chongqing, China were recruited from 2006 to 2009. Participants underwent VIA/VILI, and, if positive, received colposcopy-directed or random biopsies. Women with negative VIA/VILI or biopsy-confirmed cervical intraepithelial neoplasia (CIN) 1 lesions diagnosed in the first round of screening were re-screened in the following year with the same procedure. RESULTS: In total, 10,269 women received VIA/VILI. The average age of participants was 40.9 ± 7.6 years. Overall, 0.85% (87/10,269) of women were diagnosed via pathology-confirmed biopsy with CIN1, 0.25% (26/10,269) with CIN2, 0.27% (28/10,269) with CIN3, and 0.02% (2/10,269) with cervical cancer. Over half (57.7%) of CIN2 lesions, the majority of CIN3 lesions (89.3%), and all cancer cases (100%) were detected in the first round of screening. CONCLUSION: In a rural, low-resource setting in China, one-time VIA/VILI screening detected more than a half of CIN2 cases, most CIN3 cases and all the cervical cancer cases. Detection rates of CIN2 lesions significantly increased with a 1-year follow-up VIA/VILI screen. Therefore, if multiple cervical cancer screenings are not feasible logistically or financially, a one-time VIA/VILI may be the most efficient strategy to detect cervical cancer and most CIN3 lesions in women in low-resource settings.

[Complication of laparoscopic radical hysterectomy and lymphadenectomy: an analysis of 23 cases].

OBJECTIVE: To explore complications of laparoscopic radical hysterectomy and lymphadenectomy in patients with cervical and endometrial carcinoma, and its prevention. METHODS: From July 2000 to December 2004 at our institution, a total of 278 laparoscopic radical hysterectomy and lymphadenectomy procedures were performed in 242 patients with cervical carcinoma and 36 patients with endometrial carcinoma. We reviewed the clinical data of patients who underwent laparoscopic radical hysterectomy and lymphadenectomy to check their complications and other factors related to this open surgical procedure. RESULTS: All but 4 surgical procedures were completed laparoscopically. Paraaortic lymphadenectomy was performed in 108 patients and pelvic lymphadenectomy was performed in all of 278 patients. Major and minor intraoperative complications occurred in 4.7% (13/278) of patients. The overall conversion rate was 1.4% (4/278), consisting of 3 emergency and 1 elective conversions. Vascular injuries occurred in 7 patients, five of them were repaired or treated laparoscopically and one left external iliac vein injury required laparotomy, another patient underwent laparotomy to control bleeding. Operative cystotomies occurred in 4 patients and all were repaired laparoscopically. One patient underwent laparotomy because of hypercapnia. Another patient underwent laparotomy because of ascending colon injury. Postoperative surgery complications occurred in 3.6% (10/278) of patients. Three patients had a ureterovaginal fistula and three patients had a vesicovaginal fistula after the operation that required reoperation. There was one patient with ureterostenosis while three patients with urinary retention. CONCLUSIONS: Laparoscopic radical hysterectomy in combination with lymphadenectomy is becoming a routine procedure in the armamentarium of many gynecologists. Complications that are unique to laparoscopy exist but they decrease with more practice and experience.

[Laparoscopic suture uterosacral ligament hysteropexy for uterine prolapse].

OBJECTIVE: To investigate possibility and effect of laparoscopic suture uterosacral ligament hysteropexy or colpopexy for women with uterine prolapse. METHODS: Thirty-two women with symptomatic uterine prolapse underwent laparoscopic suture uterosacral ligament hysteropexy. At the laparoscopic suture hysteropexy or colpopexy, the pouch of Douglas was closed and the uterosacral ligaments were plicated and reattached to the cervix. All patients were multipara and menopausal with prolapse of anterior wall of vagina. Additionally, 4 patients were with prolapse of posterior wall of vagina, 15 with stress urinary incontinence, and 4 with myomas. RESULTS: All procedures were successfully completed laparoscopically. The mean operating time for the laparoscopic suture hysteropexy or colpopexy alone was (32 +/- 11) min (range 20 approximately 80 min), and the mean blood loss was less than 50 ml. After a mean follow-up of (12 +/- 6) months (range 4 approximately 28 months), 23 women had no symptoms of uterine prolapse and seven had no objective evidence of uterine prolapse. Two women presented recurrence of uterine prolapse 3 months after operation. CONCLUSIONS: The laparoscopy suture hysteropexy or colpopexy is effective and safe in the management of symptomatic uterine prolapse. It may be an appropriate procedure for women with uterine prolapse hoping for uterine preservation.