[Occupational hazard analysis of workers exposed to chromate in a steel plant].

Objective: To investigate the occupational damage to workers exposed to chromate in a steel plant. Methods: In January 2021, a retrospective analysis was used to select 850 workers exposed to chromate (observation group) and 598 workers not exposed to chromate (control group) in a steel plant in Shandong Province from 2016 to 2017 as the investigation. We collected their occupational-related information, blood routine, fasting blood sugar, nasal lesions, skin lesions, chest X-rays and other inspection results, compared the differences in the abnormal detection rate of the two groups of respondents, and analyzed the occupational hazards of chromium workers. Results: Incidence of nasal damage, skin lesion, up-regulation of ALT (Alanine aminotransferase), abnormal chest radiograph, abnormal serum biochemical index, and abnormal serum glucose level were observed higher in the exposed group than those in the control group (χ(2)=125.69, 12.25, 5.82, 10.37, 10.46, 20.66, P=0.000, 0.000, 0.016, 0.001, 0.001, 0.000). Among the symptoms, the incidence of erythra, nasal septum deviation, nasal mucosal congestion, nasal mucosal erosion and rhinitis were more frequent than those in the control group (χ(2)=101.54, 4.07, 13.20, 32.05, P=0.000, 0.044, 0.000, 0.000). There was no significant increase in the incidence of work type, age, length of work and the area of nasal mucosa erosion in the observation group compared with the control table, and the difference was not statistically significant (χ(2)=5.31、0.42、0.28, P=0.505, 0.662, 0.871) . Conclusion: Occupational hazards of long-term exposure to chromate cannot be ignored. Attention should be paid to strengthening occupational protection and health education of workers exposed to chromium, and increasing their attention.

Recurrent umbilical varix rupture with hemoperitoneum: a case report and review of literature.

BACKGROUND: Non-traumatic hemoperitoneum was a rare event with the risk of sudden death. Spontaneous rupture of hepatocellular carcinoma is the most intuitive diagnosis when hemoperitoneum occurs in cirrhotic patients who are not regularly followed up. However, other etiologies of hemoperitoneum, such as intra-abdominal varix rupture, should be kept in mind. CASE PRESENTATION: A 44-year-old man with alcoholic liver cirrhosis, Child-Pugh B was sent to our emergency department (ED) because of recurrent abdominal pain and hypovolemic shock. He had similar symptoms one month ago and was diagnosed as hepatocellular carcinoma (HCC) rupture with hemoperitoneum, therefore he underwent trans-arterial embolization (TAE). However, the follow-up magnetic resonance imaging (MRI) showed less possibility of hepatocellular carcinoma. Contrast enhanced abdominal computed tomography (CT) showed possible umbilical vein contrast agent extravasation. Exploratory laparotomy confirmed the diagnosis of rupture umbilical varix with hemoperitoneum. CONCLUSION: Although umbilical varix rupture is a rare cause of hemoperitoneum, it should be kept in mind in cirrhotic patients with unexplained hemoperitoneum.

Hepatocellular carcinoma progression is protected by miRNA-34c-5p by regulating FAM83A.

OBJECTIVE: To elucidate the role of microRNA-34c-5p (miRNA-34c-5p) in the progression of hepatocellular carcinoma (HCC) and the indicated mechanism. PATIENTS AND METHODS: Relative levels of miRNA-34c-5p and FAM83A in HCC tissues and cell lines were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Their influences on clinical features in HCC patients were analyzed. Kaplan-Meier method was introduced for assessing the relationship between miRNA-34c-5p and overall survival in HCC. After overexpression of miRNA-34c-5p in HepG2 and HB611 cells, we detected proliferative, migratory and invasive abilities by cell counting kit-8 (CCK-8) and transwell assay. The interaction between miRNA-34c-5p and FAM83A was explored by Dual-Luciferase reporter assay. Finally, their co-regulation on HCC cell phenotypes was examined. RESULTS: MiRNA-34c-5p was downregulated in HCC tissues, especially stage III+IV cases. Its level was correlated to tumor size, tumor number and TNM staging in HCC. Overexpression of miRNA-34c-5p inhibited proliferative, migratory and invasive abilities in HepG2 and HB611 cells. In addition, miRNA-34c-5p targeted on FAM83A and negatively regulated its level. Overexpression of FAM83A could reverse the inhibitory effects of miRNA-34c-5p on malignant phenotypes of HCC cells. CONCLUSIONS: By negatively regulating FAM83A level, miRNA-34c-5p alleviates the progression of HCC.

[Clinical analysis of 24 cases of occupational chromium rhinopathy].

Occupational chromium rhinopathy is chronic nasal damage caused by chromic anhydride, chromate and dichromate 6-valent chromium compounds. In 2016, 700 people who were exposed to chromium slag in steel plant were checked out. 24 people were found to have nasal injuries. The expert group confirmed 1 case of occupational severe chromium rhinosis and 23 cases of occupational mild chromium rhinosis.There was no significant difference in the incidence, type of work and duration of injury among 24 patients (P>0.05) . Active measures should be taken to prevent chromium rhinopathy and the technological process should be reformed. Occupational health education and occupational health monitoring should be strengthened to avoid exposure of chromium and its compounds through nose and respiratory tract, and to reduce or eliminate the occurrence of chromium rhinosis.

[Association between dietary magnesium and the risk of type 2 diabetes in Harbin residents].

Objective: To investigate the relationship between the magnesium intake and patterns of diary and the risk of type 2 diabetes in Harbin residents. Methods: On April 2010, 24 communities in 7 districts of Harbin were selected as research sites using multi-stage stratified random cluster sampling method. A total of 9 734 residents aged 20-74 years was investigated using general questionnaire survey, dietary survey and biochemical indicators test. A total of 9 376 subjects were included in the study. Factor analysis was used to analyze dietary patterns. According to the quartile of dietary magnesium intake, the subjects were divided into four groups, from Q(1) to Q(4) group. The multivariate logistic regression model was used to analyze the relationship between dietary magnesium intake and the risk of type 2 diabetes within different dietary patterns. Results: A total of 998 subjects with type 2 diabetes were screened. The median age of the diabetic group and the non-diabetic group were 54.8 and 50.8, respectively, and the males accounted for 43.4% (2 896 cases) and 34.6% (433 cases), respectively. The magnesium intake median (P(25), P(75)) of two groups was 336.36 (257.31, 440.65) and 339.50 (264.51, 443.78) mg/d. Four dietary patterns were identified as western dietary mode, savvy dietary mode, traditional dietary mode, and staple food mode. In the western dietary model, the Q(4) group had a higher risk of type 2 diabetes than Q(1) group, with an OR (95%CI) value of 1.56 (1.06 to 2.32). However, in the savvy diet mode, compared with the Q(1) group, the risk of diabetes in the Q(4) group was lower, and the OR (95%CI) value was 0.61 (0.37 to 0.96). There was no statistically significant association between dietary magnesium intake and the risk of type 2 diabetes without considering dietary patterns (P>0.05). Conclusion: Dietary magnesium intake has a different relationship with the risk of type 2 diabetes within different dietary patterns.

Robot-assisted thoracoscopic esophagectomy with extensive mediastinal lymphadenectomy: experience with 114 consecutive patients with intrathoracic esophageal cancer.

The study aims to report the operative outcomes of robot-assisted thoracoscopic esophagectomy (RATE) with extensive mediastinal lymphadenectomy (ML) for intrathoracic esophageal cancer. We analyzed a prospective database of 114 consecutive patients who underwent RATE with lymph node dissection along recurrent laryngeal nerve (RLN) followed by cervical esophagogastrostomy. The study included 104 men with a mean age of 63.1 ± 0.8 years. Of these, 110 (96.5%) had squamous cell carcinoma, and the location of the tumor was upper esophagus in 7 (6.1%), middle in 62 (54.4%), and lower in 45 (39.5%). Preoperative concurrent chemoradiation was performed in 15 patients (13.2%). All but one patient underwent successful RATE, and R0 resection was achieved in 111 patients (97.4%). Extended ML and total ML were performed in 24 (21.1%) and 90 (78.9%) patients, respectively. Total operation time was 419.6 ± 7.9 minutes, and robot console time was 206.6 ± 5.2 minutes. The mean number of total, mediastinal, and RLN nodes was 43.5 ± 1.4, 24.5 ± 1.0, and 9.7 ± 0.7, respectively. The most common complication was RLN palsy (30, 26.3%), followed by anastomotic leakage (17, 14.9%) and pulmonary complications (11, 9.6%). Median hospital stay was 16 days, and 90-day mortality was observed in three patients (2.5%). On multivariate analysis, preoperative concurrent chemoradiation was a risk factor for pulmonary complications (odds ratio 7.42, 95% confidence interval 1.91-28.8, P = 0.004). RATE with extensive ML could be performed safely with acceptable postoperative outcomes. Long-term survival data should be followed in the future to verify the oncological outcome of the procedure.

Polyphyllin D induces apoptosis in human erythrocytes through Ca²âº rise and membrane permeabilization.

Polyphyllin D (PD) is a potent anticancer agent isolated from a traditional medicinal herb Paris polyphylla that has been used in China for many years to treat cancer. PD is not a substrate of p-glycoprotein, and it can bypass the multi-drug resistance in cancer cell line R-HepG2. However, the effect of PD on the induction of cell death in human erythrocytes remains unknown. Given that PD is a small molecule that can depolarize the mitochondrial membrane potential and release apoptosis-inducing factor (AIF) in isolated mitochondria, we hypothesized that the apoptogenic effect of PD in human erythrocytes devoid of mitochondria would be minimal. This study therefore tried to evaluate the in vitro effect of PD on hemolysis and apoptosis in human erythrocytes. Apoptosis in human red blood cells (RBCs), also known as eryptosis or erythroptosis, after PD treatment was determined by flow cytometry and confocal microscopy for the phosphatidyl-serine externalization and other apoptosis feature events. False to our prediction, PD caused hemolysis and eryptosis/erythroptosis in human RBCs. Mechanistically, elevation in the cytosolic Ca²âº ion level seems to be a key but not the only mediator in the PD-mediated eryptosis/erythroptosis because depletion of the external Ca²âº could not eliminate the PD effect. Also, PD was able to permeabilize the membrane of RBC ghosts in a way similar to digitonin. Taken together, we report here for the first time the toxicity of PD in human RBCs as well as its underlying mechanism for the hemolysis and eryptosis/erythroptosis.

Limits to the control of the human thumb and fingers in flexion and extension.

In humans, hand performance has evolved from a crude multidigit grasp to skilled individuated finger movements. However, control of the fingers is not completely independent. Although musculotendinous factors can limit independent movements, constraints in supraspinal control are more important. Most previous studies examined either flexion or extension of the digits. We studied differences in voluntary force production by the five digits, in both flexion and extension tasks. Eleven healthy subjects were instructed either to maximally flex or extend their digits, in all single- and multidigit combinations. They received visual feedback of total force produced by "instructed" digits and had to ignore "noninstructed" digits. Despite attempts to maximally flex or extend instructed digits, subjects rarely generated their "maximal" force, resulting in a "force deficit," and produced forces with noninstructed digits ("enslavement"). Subjects performed differently in flexion and extension tasks. Enslavement was greater in extension than in flexion tasks (P = 0.019), whereas the force deficit in multidigit tasks was smaller in extension (P = 0.035). The difference between flexion and extension in the relationships between the enslavement and force deficit suggests a difference in balance of spillover of neural drive to agonists acting on neighboring digits and focal neural drive to antagonist muscles. An increase in drive to antagonists would lead to more individualized movements. The pattern of force production matches the daily use of the digits. These results reveal a neural control system that preferentially lifts fingers together by extension but allows an individual digit to flex so that the finger pads can explore and grasp.

Thumb and finger forces produced by motor units in the long flexor of the human thumb.

The uncommonly good proprioceptive performance of the long flexor of the thumb, flexor pollicis longus (FPL), may add significantly to human manual dexterity. We investigated the forces produced by FPL single motor units during a weak static grip involving all digits by spike-triggered averaging from single motor units, and by averaging from twitches produced by intramuscular stimulation. Nine adult subjects were studied. The forces produced at each digit were used to assess how forces produced in FPL are distributed to the fingers. Most FPL motor units produced very low forces on the thumb and were positively correlated with the muscle force at recruitment. Activity in FPL motor units commonly loaded the index finger (42/55 units), but less commonly the other fingers (P < 0.001). On average, these motor units produced small but significant loading forces on the index finger ( approximately 5.3% of their force on the thumb) with the same time-to-peak force as the thumb ( approximately 50 ms), but had no significant effect on other fingers. However, intramuscular stimulation within FPL did not produce significant forces in any finger. Coherence at 2-10 Hz between the thumb and index finger force was twice that for the other finger forces and the coherence to the non-index fingers was not altered when the index finger did not participate in the grasp. These results indicate that, within the long-term coordinated forces of all digits during grasping, FPL motor units generate forces highly focused on the thumb with minimal peripheral transfer to the fingers and that there is a small but inflexible neural coupling to the flexors of the index finger.

Electron-impact ionization of CCl4 and CCl2F2.

Absolute partial and total cross sections for electron-impact ionization of CCl4 and CCl2F2 are reported for electron energies from threshold to 1000 eV. The product ions are mass analyzed using a time-of-flight mass spectrometer and detected with a position-sensitive detector whose output demonstrates that all product ion species are collected with equal efficiency irrespective of their initial kinetic energies. Data are presented for production of CCl3(+), CCl2(+), CCl+, C+, Cl2(+), and CCl3(2+) from CCl4; and for production of CCl(2)F+, CClF2(+), CClF(+), (CCl+ + CF2(+)), Cl+, CF+, F+, and C+ from CCl2F2. Data are also reported for formation of (CCl2(+),Cl+) and (CCl+, Cl+) ion pairs from CCl4. The total cross section for each target is obtained as the sum of the partial cross sections. The overall uncertainty in the absolute cross sections for most of the singly charged ions is +/- 5-7 %. The present partial cross sections for lighter fragment ions are found to be considerably greater than had been previously reported but the most recent total cross section measurements agree well with those reported here. Neither the binary-encounter-Bethe theory nor the Deutsch-Mark theory reproduces the experimental cross sections correctly for both targets.

Expression of heat shock protein 72 in rat cochlea with cisplatin-induced acute ototoxicity.

Cisplatin ototoxicity is known to involve mainly the organ of Corti. Outer hair cells (OHCs). especially in the basal turn, are preferentially involved. One possible mechanism of ototoxicity might be alteration of the antioxidant system causing an increase in free radicals. It has been demonstrated that heat shock proteins (HSPs), which are believed to protect cells by dissolving and refolding misfolded or denatured protein are induced by various form of stress. HSP is also demonstrated to be induced by free radicals. The purpose of this study was to evaluate HSP 72 induction in cochlea following cisplatin injection in the animal model. Sprague-Dawley (SD) rats were injected intraperitoneally with normal saline as control or cisplatin at a dose of 5, 10 or 20 mg/kg. Cochleae were harvested 1, 3, 6 and 12 h after injection and compared with those of controls. Immunocytochemical study with surface preparation and Western blotting were performed to investigate the expression of HSP 72. Auditory brainstem response (ABR) was also recorded to assess functional change according to the dosage of cisplatin and duration after injection. In the 5 and 10 mg/kg groups, immunostaining for HSP 72 in the OHCs reached a plateau level at 3 h, which was maintained until 12 h after injection. The amount of immunoreactive OHCs in the 20 mg/kg group was smaller than those in 5 and 10 mg/kg groups and declined after 6 h. The bands for HSP 72 became less intense as the cisplatin dosage increased from 5 to 10 and 20 mg/kg in Western blotting. The change in ABR threshold was small in the 5 and 10 mg/kg groups and a marked change in threshold was observed in the 20 mg/kg group. Detection of HSP 72 after cisplatin injection could confirm the OHCs as one of the major injured cells in the cochlea. With a lethal dosage of cisplatin (20 mg/kg), HSP 72 expression was less prominent and declined after 6 h.

The effects of experimentally increased perilymphatic pressure on click-evoked otoacoustic emissions in guinea pigs.

We used the IL088 Otodynamic Analyzer system to study click-evoked otoacoustic emissions (CEOAEs) in 30 healthy guinea pigs. The animals were anesthetized and patterns of the CEOAEs were evaluated before manipution, after the tympanic bulla was opened, and after formation of a microfistula on the basal turn of the cochlea. The animals then were divided into three pressure loading groups (10, 20, and 30 cm H2O). CEOAEs were recorded with a capillary manometer at pretest, 5, 10, 20, 30, 45, and 60 min after perilymphatic pressure loading to the basal turn of cochlea, and 10 and 20 min after pressure unloading. As perilymphatic pressure increased, all three pressure groups showed maximum decreases in both echo response and reproducibility 5 min after pressure loading. In the 10 cm H2O pressure group, emissions recovered 10 min after pressure loading, and this tendency continued. However, in the 20 and 30 cm H2O pressure groups, no recovery of emissions was seen throughout the 60 min observation period, except for emissions after pressure unloading. The results suggest that the echo response and reproducibility may be sensitive indicators of cochlear function and perilymphatic pressure regulation capacity.

Contribution of neurons born during embryonic, juvenile, and adult life to the brain of adult canaries: regional specificity and delayed birth of neurons in the song-control nuclei.

Neurogenesis occurs in adult song birds, which suggests that neurons born after hatching may contribute to histogenesis and plasticity of the avian brain. However, little is known about the overall contribution to the mature brain of neurons born in juveniles and adults, and how this process affects different regions of the avian brain. In fact, studies of the histogenesis of the avian forebrain have made the classical assumption that neuronal birth ends before hatching. Here we determined the contribution of neurons born before and after hatching to different regions throughout the adult canary brain. Male canaries were injected with [3H]-thymidine at different times during embryonic, juvenile, and adult life. The position of labeled neurons was mapped in parasagittal brain sections. Because all birds were killed as adults, results indicate the time of birth of neurons that survived to adulthood in different structures of the avian brain. Injection at embryonic day (E) 5 or E9 resulted in labeled neurons in all regions of the neuroaxis. The vast majority of neurons outside of the telencephalon were born before E9. One exception was a discrete region in the dorsal thalamus, a part of the song-control circuit, where neurons continued to be born after E9. Most regions of the telencephalon had a high proportion of its neurons labeled by the embryonic injections. In particular, archistriatum, anterior neostriatum, and the hippocampus had most of their neurons labeled before hatching. This indicates that many of the telencephalic neurons born in the embryo are long lived and are not replaced by other neurons that continue to be added to the telencephalon after hatching. Neurons labeled by [3H]-thymidine injections after hatching were restricted to the telencephalon and contributed importantly to many regions. In particular, the avian striatum (lobus parolfactorius, LPO) received a large number of its neurons during the first 20 days of life, but continued to incorporate new neurons throughout juvenile and adult life. Neurons continued to be added to the telencephalon of adults (even in 4-year-old birds). The distribution of labeled neurons after [3H]-thymidine injections in adults was similar to that observed in latter stages of juvenile development. The contribution of neurons born at different ages from embryonic development to adulthood varied among different anatomical subdivisions of the canary brain. this could, in part, explain differences in the cytoarchitecture and plasticity between brain regions. Neurogenesis after hatching may allow the modification of selected brain circuits as the bird matures and ages.

Polyphenols from Rhodiola crenulata.

A novel gallotannin, crenulatin ( 7), has been isolated from RHODIOLA CRENULATA. The structure was elucidated by spectral analyses (including 2D-NMR spectral measurements) and chemical methods. Also six known polyphenols have been isolated and identified.

Evaluation of a nutrition education activity for medical students in China.

In China, where cancers and cardiovascular disease are the major causes of morbidity and mortality, an important role for preventive medicine has emerged. Therefore, preparing China's medical students to tackle contemporary health problems requires attention to nutrition and health promotion in the medical curriculum. To evaluate the effectiveness of a nutrition education activity for medical students, a two-group pre-test/post-test nutrition education program was conducted in a medical university in south-western China (n=300 per group). Students in another south-western Chinese medical university served as controls (n= 150 per group). Special features of the intervention were: (1) nutrition education materials developed from (a) the results of a pre-test survey of medical students and (b) discussions with medical students, faculty, and physicians; and (2) a multi-channel delivery, which included a classroom lecture-discussion; a nutrition knowledge competition; a handout providing a day's dietary allotment; campus radio and movie theatre announcements, and posters. Analysis of variance, chi-square, and t-tests showed a significant increase (P<0.05) in nutrition knowledge, but not in nutrition attitude score. The final nutrition knowledge and attitude scores were also found to be related to the students' increased exposure to the various channels (P<0.001). Also observed was an increase in the consumption of soybean and dairy products (P<0.05). It is concluded that the method is a useful and practical model for designing and developing student nutrition education activities in China, as well as demonstrating nutrition and health education methods among the medical university community.

Cyst fluid proteases.

The precise origin of breast cyst fluid remains obscure. Molina has presented evidence that type II cysts (high Na/K ratio) may be transudative, that is, partly derived from plasma elements which enter through gap junctions, while Type I cysts (high K/Na ratio) are primarily secretory. In transudative cysts, plasma protease inhibitors may be present, but the balance between protease and its inhibitors may fluctuate as a result of as yet undetermined circumstances. An imbalance between the protease activity of cyst fluid and its inhibitors may be involved in the pathogenesis of breast gross cystic disease. Accumulation of protein fragments with resistant bonds would produce an elevated oncotic pressure causing a shift of fluid into the cyst capsule. Albumin is a good substrate for the protease, which may account for its low concentration in cyst fluid. The major protease fraction closely corresponds to the progesterone binding protein (GCDFP-24) described by Haagensen. Affinity columns containing aprotinin or benzamidine ligands retain the protease which can then be eluted with 0.5 M NaCl. The HD1 protease and progesterone binding protein are either tightly complexed or are the same protein. Cyst fluid is a complex mixture of biomolecules. If the progesterone binding protein is a protease, many questions must be answered concerning the influence of cyst fluid steroids, lipids, anions, and cations on enzyme action. Determination of the amino acid sequence of HD1 may help elucidate the source of the enzyme and its relationship to other tissue proteases. Human plasma contains inhibitors of this protease activity. When pooled, dialyzed plasma was mixed with pooled, dialyzed cyst fluid, the ratio of plasma/cyst fluid at which all activity was inhibited was 6/1. A comparison of the rate of cleavage of three 14C-protein substrates shows that cyst fluid proteases cleave in a characteristic manner, distinct from either trypsin or calpain. A simple method for semiquantitative estimation of protease activity in cyst fluid is described which utilizes prestained Coomassie blue-albumin containing agarose gel plates. All cyst fluids tested had protease activity but showed variability in their ability to cleave 14C-albumin by a factor of 4. There is much direct and indirect evidence that proteases are involved in the cancer process. In view of the higher than normal incidence of breast cancer in women who have had gross cystic breast disease, the possibility exists that an imbalance between these proteases and their inhibitors is somehow involved.