[Posterior inferior cerebellar artery infarction with episodic postural diplopia as the initial symptom: A case report].

Accurate and timely diagnosis of posterior circulation ischemic stroke is a challenge for emergency neurology clinicians, even MRI scan which is believed to be sensitive to acute ischemic lesions may be negative. It is particularly important to obtain the typical or characteristic symptoms and signs of the patients through comprehensive physical examination. We report a case of posterior inferior cerebellar artery (PICA) territory infarction with "episodic postural diplopia" as the initial symptom, hoping that clinicians notice the vertical diplopia caused by the disfunction of otolith gravity conduction pathway, which is characterized by the degree of diplopia being affected by postural changes. A 44-year-old man was in hospital due to episodic postural diplopia for 4 months, dizziness and unstable walking for 5 days. In the past four months, the patient had endured episodic diplopia attack for 8 times when standing or walking, which could be relieved obviously while lying down and gradually disappeared within 5-10 minutes. He had not seen a doctor since the outbreak of the novel coronavirus. Five days before admission, diplopia worsened accompanying obvious vertigo, nausea and vomiting, left facial numbness, and hiccups. The diplopia could be relieved after taking the supine position, but not completely disappear as before. Physical examination showed a triad of ocular tilt response (OTR), namely static ocular rotation (SOT), skew deviation (SD) and head tilt (HT). And also subjective visual vertical (SVV) deviation was found. Those signs were considered for otolith gravity conduction system involvement. Combined with other clinical signs, such as Horner signs, crossed sensory disorders, ataxia, and MRI scan, it was easy to find the infarction was in the territory of the left PICA. The reasons for the patient's "episodic posi-tional diplopia" in the early stage of the disease were considered as follows: (1) the gravity was less affected in the supine position, the stimulation of the otolith gravity conduction pathway was reduced, so the degree of eye deviation was reduced in the supine position. (2) As an ischemic cerebrovascular disease, the patient experienced a process of transient ischemic attack (TIA) in the posterior circulation, the cerebral blood supply and the hypoperfusion of stenosis were increased after lying down, so the diplopia symptom disappeared. The upright-supine test was recommended for the patients with vertical diplopia. It was recommened to differentiate between otolith pathway involvement and diplopia caused by trochlear nerve palsy.

[Clinical application analysis of a method for locating scalp projection of intracranial lesions based on neuroimaging].

Objective: To explore the feasibility of a method based on neuroimaging and surface markers for locating scalp projection of intracranial lesions. Methods: The clinical data of 46 patients who were used 'double-circle method' for locating scalp projection of intracranial lesions at Department of Neurosurgery,the First Affiliated Hospital of Xiamen University from January to June 2021 were retrospective analyzed. All patients with 2 electrodes(artificial fiducials) randomly attached to scalp had been examed thin-layer brain CT. The distances from the center of each fiducial to the root of the nose and tragus were measured through the images. A compass was used to draw two arcs with the root of nose and the tragus as the center and the pre-measured distance as the radius on patient's scalp. Then two arcs' intersection on the scalp was the fiducial. The method was named 'double-circle method'. Two neurosurgeons were arranged to perform fiducial identification with double-circle method, and record the error between the result and the actual fiducial point.Independent sample t test was used for data comparison, and Kappa test was used to analysis the inter-group consistency. Results: Ninety-two fiducial points of 46 patients were collected. Time consuming of doctor A was (8.1±2.3) minutes(range:5 to 15 minutes)and doctor B was (8.9±3.5) minutes(range:4 to 17 minutes).The positioning error from the doctor A was (4.4±2.4)mm(range:0 to 12 mm) and doctor B was(4.2±2.6) mm(range:0 to 14 mm)(t=-0.575,P=0.567),the difference was not statistically significant. The Kappa value of the consistency test of error between two doctors was 0.517(P=0.001).The consistency was moderate.Eight patients used 'double-circle method' and neuronavigation for locating scalp projection of intracranial lesions at the same time. The diameter of the lesions was (3.8±0.9)cm (range: 2.6 to 5.1 cm), and the positioning error of the 'double-circle method' and navigation was (4.0±1.9) mm(range: 1 to 6 mm), and all patients were confirmed to be accurately located during surgery. Conclusion: 'Double-circle method' is a simple,convenient and accurate way in locating intracranial lesions and has certain clinical significance.

The δ30Si peak value discovered in middle Proterozoic chert and its implication for environmental variations in the ancient ocean.

The silicon isotope composition of chert has recently been used to study the historic evolution of the global ocean. It has been suggested that Precambrian cherts have much higher δ30Si values than Phanerozoic cherts do and that the former show an increasing trend from 3.5 to 0.85 Ga, reflecting a decrease in ocean temperatures. However, cherts have various origins, and their isotopic compositions might be reset by metamorphic fluid circulation; thus, different types of cherts should be distinguished. Here, we present a new set of δ30Si data for cherts from early and middle Proterozoic carbonate rocks from Northern China. We found that cherts of 1.355-1.325 Ga show a peak range of 2.2-3.9‰. Based on these results, we propose that from the Archean to the middle Proterozoic, there was a drastic decrease in silicon content and an increase in the δ30Si value in ocean water due to a temperature decrease and biological activity increase. After that period, the silicon content of the ocean was limited to a low level by a high degree of biological absorption, and their δ30Si values varied in a small range around a significantly lower value.

[Impact of atmospheric particulate matter at different period of gestation on low birth weight: a meta-analysis].

Objective: To analyze the influence of atmospheric particulate matters (PM(2.5) and PM(10)) on low-birth-weight (LBW) infants at different periods of gestation. Methods: We conducted a systematic literature search for 2 471 articles related to particulate matter and LBW published from January 1st 2000 to January 1st 2016 using the PubMed, Cochrane Library, Web of Science, Science Direct, Chinese Web of Knowledge, Wanfang and Weipu, and the keywords were" air pollution" , "adverse birth outcomes" , "adverse pregnancy outcomes" , "low birth weight/LBW" . According to criteria, 27 literatures were selected and included. Metafor package of the R 3.1.1 Software was used to check the heterogeneity and merge the effect value of the selected literatures, and sensitivity analysis and publication bias were detected and adjusted. Results: A total of 2 471 studies selected form the databases, 27 enrolled in this analysis according to the inclusion and exclusion criteria. Each 10 µg/m(3) increase in PM(2.5) was associated with combined OR values of 1st trimester, 2nd trimester, 3rd trimester and entire gestation at 1.02(95% CI: 0.87-1.19), 1.03 (95% CI: 0.91-1.16) , 1.07 (95%CI: 1.04-1.11) and 1.09 (95%CI: 1.04-1.15), respectively. And 10 µg/m(3) increase in PM(10) was associated with combined OR values of 1st trimester, 2nd trimester, 3rd trimester and entire gestation at 1.66 (95%CI: 1.06-2.61), 1.58 (95%CI:1.28-1.95) , 1.38 (95%CI: 1.23-1.56) and 1.04 (95%CI: 0.99-1.09), respectively. After adjusting the bias of publication, each 10 µg/m(3) increase in PM(2.5) was associated with the risk of low birth weight at 1.11 (95%CI: 1.02-1.21). Conclusion: This meta analysis supports an adverse impact of maternal exposure to particulate air pollution on low birth weight, varying in effects by exposure period.

The effects of cleanroom noise intensity and frequency on physiological measures and subjective responses.

BACKGROUND: Workplace noise exposure gains growing attention in high tech industry. OBJECTIVE: This study investigated the noise effect on physiological and subjective responses in semiconductor manufacturing clean room environment. METHODS: Twenty subjects including 10 males and 10 females completed all phases of the experiment. Each subject was asked to participate in four treatment combinations of two noise intensities [65 dB(A) and 80 dB(A)] × two frequency levels [high and low]. For each treatment condition, the subject was exposed to the specified noise condition in a sound proof cabin for one hour. The physiological measures included blood pressure and heart rate. The subjective measures included noise sensitivity, fatigue and annoyance. RESULTS: The ANOVA results indicate that long-time noise exposure caused significant increase in blood pressure (p< 0.001). Furthermore, the noise intensity by time interaction effect was found to be significant on annoyance and fatigue. CONCLUSIONS: The findings suggest that prolonged exposure to noise intensity at 80 dB(A) would result in a significant increase in physiological cost and subjective discomfort feeling. Thus, some countermeasures should be taken to reduce noise exposure and to promote health, and quality of working life.

Acupressure treatment for prevention of postoperative nausea and vomiting.

Postoperative nausea and vomiting are still common problems after general anesthesia, especially in ambulatory surgery. Drug therapy is often complicated with central nervous system symptoms. We studied a nonpharmacological method of therapy--acupressure--at the Pericardium 6 (P.6) (Nei-Guan) meridian point. Two hundred consecutive healthy patients undergoing a variety of short surgical procedures were included in a randomized, double-blind study: 108 patients were in the acupressure group (Group 1) and 92 patients were in the control group (Group 2). Spherical beads of acupressure bands were placed at the P.6 points in the anterior surface of both forearms in Group 1 patients, while in Group 2 they were placed inappropriately on the posterior surface. The acupressure bands were placed before induction of anesthesia and were removed 6 h postoperatively. They were covered with a soft cotton wrapping to conceal them from the blinded observer who evaluated the patients for presence of nausea and vomiting and checked the order sheet for any antiemetics prescribed. In both groups, the age, gender, height, weight, and type and duration of surgical procedures were all comparable without significant statistical difference. In Group 1, only 25 of 108 patients (23%) had nausea and vomiting as compared to Group 2, in which 38 of 92 patients (41%) had nausea and vomiting (P = 0.0058). We concluded that acupressure at the P.6 (Nei-Guan) point is an effective prophylaxis for postsurgical nausea and vomiting and therefore a good alternative to conventional antiemetic treatment.