A large cross-sectional study to investigate the prevalence and possible modes of transmission of Helicobacter pylori was done in southern China. Serum samples (1727) were collected from Guangzhou city and three rural areas of Guangdong Province, and the prevalence of H. pylori infection was determined using an ELISA. Each subject completed a questionnaire. The overall prevalence of H. pylori infection was 44.2%; a significantly higher prevalence was found in Guangzhou (52.4%) than in the rural areas (38.6%). This difference was generally reflected in the group 0-5 years old, but the rate of increase in seroprevalence for H. pylori over 5 years of age was similar (1%/year). This study provides important new data on the acquisition of H. pylori, particularly in the early years of life, and shows that density of living conditions is a prime determinant in the acquisition of H. pylori.

Permanent magnet synchronous machines (PMSMs) can provide excellent performance in terms of torque density, energy efficiency and controllability. However, PMs on the rotor are prone to the centrifugal force which may break their physical integrity, especially at high-speed operation. Typically, PMs are bound with carbon fiber or retained by alloy sleeves on the rotor surface. This paper is concerned with the design of a rotor retaining sleeve for a 1.12-MW 18-krpm PM machine; its electromagnetic performance is investigated by the 2D finite element method (FEM). Theoretical and numerical analysis of the rotor stress are carried out. For the carbon fiber protective measure, the stresses of three PM configurations and three pole filler materials are compared in terms of operating temperature, rotor speed, retaining sleeve thickness, and interference fit. Then a new hybrid protective measure is proposed and analyzed by the 2D FEM for operational speeds up to 22 krpm (1.2 times the rated). The rotor losses and machine temperatures with the carbon fiber retaining sleeve and the hybrid retaining sleeve are compared and the sleeve design is refined. Two rotors using both designs are prototyped and experimentally tested to validate the effectiveness of the developed techniques for permanent magnet machines. The developed retaining sleeve makes it possible to operate MW PM machines at high speeds of 22 krpm. This opens doors for many high-power high-speed applications such as turbo-generators, aerospace and submarine motor drives.

Electromagnetic design of a 1.12-MW, 18,000-rpm high-speed permanent-magnet motor (HSPMM) is carried out based on the analysis of pole number, stator slot number, rotor outer diameter, air gap length, permanent magnet (PM) material, thickness and pole arc. The no-load and full-load performance of the HSPMM is investigated in this paper by using 2-D finite element method (FEM). In addition, the power losses in the HSPMM including core loss, winding loss, rotor eddy current loss and air friction loss are predicted. Based on the analysis, a prototype motor is manufactured and experimentally tested to verify the machine design.

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The aging-related changes of NADPH-diaphorase (NADPH-d) in the spinal cord were studied in aged dogs. At all levels of the spinal cord examined, NADPH-d activities were present in neurons and fibers in the superficial dorsal horn, dorsal commissure and in neurons around the central canal. In addition, the sympathetic autonomic nucleus in the thoracic and rostral lumbar segments exhibited prominent NADPH-d cellular staining whereas the sacral parasympathetic nucleus (SPN) in the sacral segments was not well stained. Interestingly, we found abundant NADPH-d positive enlarged-diameter fibers termed megaloneurite, which characteristically occurred in the aged sacral segments, distributed in the dorsal gray commissure (DGC), lateral collateral pathway (LCP) the lateral fasciculi and the central canal compared with the cervical, thoracic and lumbar segments. The dense, abnormal NADPH-d megaloneurites occurred in extending from dorsal entry zone through lamina I along with the lateral boundary of the dorsal horn to the region of the SPN. These fibers were prominent in the S1-S3 segments but not in adjacent segments L5-L7 and Cx1 or in thoracolumbar segments and cervical segments. Double staining with GFAP, NeuN, CGRP, MAP2 and Iba1, NADPH-d megaloneurite colocalized with vasoactive intestinal peptide. Presumably, the megaloneurites may represent, in part, visceral afferent projections to the SPN and/or DGC. The NADPH-d megaloneurites in the aged sacral spinal cord indicated some anomalous changes in the neurites, which might account for a disturbance in the aging pathway of the autonomic and sensory nerve in the pelvic visceral organs.

Most cases of cervical cancer are the result of infection with specific high-risk types of human papillomavirus (HPV). Investigating the genetic basis of the host immune response, particularly cytokine function, could help further characterize the progression of cervical HPV infection into neoplasia. Prior studies have demonstrated a correlation between genetic variants of tumor necrosis factor alpha (TNF-α, TNF gene) and/or interleukin-10 (IL-10, IL10 gene) and cervical cancer susceptibility. However, some of the results have been contradictory. We sought to resolve these discrepancies by carrying out our study in a large cohort of Chinese women. In order to assess the association of TNF and IL10 genotypes with cervical cancer susceptibility, the polymorphisms in TNF (−238 G/A, −308 G/A) and IL10 (−592 C/A, −819 C/T, −1082 A/G) were genotyped and odds ratios for the genotype and allele frequencies between cervical cancer patients and healthy controls were calculated. Also, the functional relevance of these polymorphisms was evaluated using enzyme-linked immunosorbent assays (ELISAs) and in vitro lymphocyte proliferation assays. The TNF-238 AA genotype frequency was lower in patients than in controls (p < 0.05). TNF-308 AA, IL10-592 CA/AA, and IL10-819 CC/CT genotype frequencies were higher in cervical cancer patients than in controls (p < 0.05). The frequency of the TNF-238 A allele was significantly lower in patients, while the frequency of the −308 A allele was significantly higher (p < 0.05). No significant differences between patients and controls were found in the genotype or allele frequencies of IL10-1082 A/G (p > 0.05). Furthermore, the combinations of TNF-238 GA or GG and IL10-592 CC; TNF-238 GA or GG and IL10-592 CA or AA; TNF-308 AA and IL10-592 CC; and TNF-308 AA and IL10-592 CA or AA in cervical cancer patients were statistically significant (p < 0.0167). Upon stimulation with PHA, peripheral blood mononuclear cells (PBMCs) with the TNF-308AA genotype exhibited significantly higher proliferation rates, elevated IL-4, TGF-β levels, and lower IL-2 levels (p < 0.05). For IL10-592C/A, the AA and CA genotypes were significantly associated with higher proliferation rates, elevated IL-4 and IL-10 levels (p < 0.05). We also found that for TNF-308 G/A or IL10-592 C/A variants, the combination of TNF-308 GG or GA with IL10 CA or AA had an association with the severity of cervical cancer. Taken together, these results suggest that TNF-308 AA and IL10-592 CA/AA genotypes may increase susceptibility to cervical cancer by altering the immune response of an individual.

Background It remains unclear whether retroperitoneal laparoscopic adrenalectomy (RLA) is safe and effective for the treatment of large pheochromocytoma (PHEO). This retrospective study aimed to identify the advantages and disadvantages of RLA compared to open adrenalectomy (OA). Methods This study included 147 patients who underwent RLA ( n = 101) or OA ( n = 46) for PHEO larger than 5 cm. Groups were balanced by propensity score matching (PSM) into 46 pairs. Perioperative variables and long-term follow-up results were compared between the two groups. Results After PSM, patients in the RLA group had a shorter operative time (218 vs. 245 min, P = 0.040), quicker bowel recovery (2 vs. 3 days, P = 0.046), and a shorter hospital stay (8 vs. 9 days, P = 0.010) compared to the OA group. The results of multiple linear regression analyses showed that the operative method (OA vs. RLA) had an influence on the above three postoperative variables ( β = 31.84, P = 0.046; β = 0.76, P = 0.044; and β = 1.25, P = 0.025, respectively). There was no significant difference in the proportion of patients with improved blood pressure (82.61% vs. 69.57%, P = 0.143) between the two groups. Conclusions Both RLA and OA provide similar perioperative and long-term outcomes for the surgical management of large PHEO. RLA is an efficacious and safe surgical method for patients with PHEO larger than 5 cm in diameter.

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