Search

The Kuroshio is the most significant current in the western North Pacific Ocean and affects a wide area. This work shows that the intrusion of the oligotrophic upper-layer West Philippine Sea seawater into the South China Sea (SCS) as the branch of Kuroshio reduced the productivity and hence the fluxes of sinking particles in the SCS between 2013 and 2017. Conversely, the productivity in the SCS increased during a large scale Kuroshio intrusion in 1998–2006, indicating that other factors also affected the productivity. Further, the western North Pacific Ocean is acidifying, with the surface seawaters to the west having lower acidification rates. This phenomenon is likely a consequence of enhanced productivity owing to more anthropogenic nutrient inputs from the continent in the west, but needs further investigation. In the East China Sea, the Kuroshio Intermediate Water has increased nutrient concentrations, but decreased in both dissolved oxygen (DO) concentration and pH, most likely owing to reduced ventilation in the North Pacific Intermediate Water. Further warming of the surface oceans would strengthen the stratification of the surface ocean, weakening ventilation. Consequently, DO and pH would continue to decline while nutrients level increases.

Like most other deep basins in Southeast Asia, the deep Sulu Sea (SS) basin is isolated from the neighboring seas by surrounding topography. While the near-surface circulation is mainly governed by the seasonally reversing monsoon winds, below the warm and fresh surface layer, the core of the incoming Subtropical Lower Water from the West Philippine Sea (WPS), by way of the South China Sea (SCS), can be seen, at a depth of around 200 m, to have a distinct salinity maximum. It lies well above the sill depth (420 m) in the Mindoro Strait and thus, its spreading is not hampered by topography. The deep circulation is forced by an inflow of upper North Pacific Intermediate Water (NPIW) from the SCS through the Mindoro Str. Below 1000 m, the physico-chemical properties are remarkably homogeneous. The higher temperature, but lower salinity, oxygen and nutrients, of the deep SS waters, compared to those of the SCS, is indicative of the intrusion of NPIW above the sill depth. The excess, anthropogenic CO2 penetrates the entire water column, because of the over-spill of the excess CO2-laden water from the SCS. It has been reported that the bottom of the SS is CaCO3 rich, relative to the SCS. Previous investigators attribute this to the higher θ in the SS. Indeed, the aragonite does not become undersaturated in the SS until below 1400 m, compared to 600 m in both the WPS and SCS; and the calcite does not become undersaturated until below 3800 m in the SS, compared to 2500 m in the SCS and around 1600 m in the WPS. However, the temperature effect is relatively small. These large differences are, in fact, largely a result of higher CO32− concentrations in the SS, relative to the WPS and SCS. The higher CO32− concentration in the SS, in turn, is mainly caused by the smaller amounts of organic carbon decomposition.

[1] Export of dissolved inorganic carbon (DIC) to adjoining oceans enhances the potential of CO2 sequestration in marginal seas. By using a series of measured DIC depth profiles and reported flow transports, we estimated that the intermediate outflow (100–600 m) from the South China Sea is capable of transporting 6.5 ± 4.1 Tg (1 Tg = 1012g) of biologically mediated carbon (DICbio) annually to the East China Sea (ECS) via the northwardly flowing Kuroshio current. The mixing and transport of these DIC-rich waters would raise 3% and 16% of DIC/TA ratio and the Revelle factor of the adjoining seawaters, respectively. Upon upwelling onto the ECS shelf, these DIC-rich waters would counteract the potential of CO2 uptake of shelf waters that might have been enhanced by the accompanying increase in nutrient inputs, thus complicating assessment of the ECS as a net CO2 source or sink.

To study the protective effects of metanephric mesenchymal cells (MMCs) on acute renal tubular damage and explore its possible mechanism.MMCs were isolated and cultured from 13-day-old embryonic rats and labeled with 5-bromodeoxyuridine. Seventy-two male SD rats were randomly divided into 3 equal groups: MMC group, receiving MMC injection instantaneously when ischemia/reperfusion (I/R) renal injury was induced, I/R group, undergoing I/R to establish acute renal tubular damage models, and sham operation group. Six rats from each group were killed at different time points: 24 h, 48 h, 72 h, and 96 h later. Blood sample was collected from the vena cava inferior, to examine the serum creatinine (SCr) and blood urea nitrogen (BUN). Specimens of kidney underwent microscopy. Apoptosis was conformed by TUNEL assay. Immunohistochemistry was used to detect the protein expression of Bcl-2 and Bax. The distribution of MMCs labeled with 5-bromodeoxyuridine in kidney was observed by immunofluorescence technique.The SCr and BUN levels in different time points of the MMC group were both significantly lower than those of the I/R group (both P0.05), HE staining showed that pathological damage of the MMC group was less than that of the I/R group (P0.05). TUNEL results investigated that the number of apoptosis renal tubular epithelial cells of the MMC group was (13.4 +/- 3.2/HPF), significantly less than that of the I/R group [(25.4 +/- 5.2/HPF)]. In comparison with the I/R group, there were more Bcl-2 positive cells and fewer Bax positive cells in the MMC group. BrdU-labeled MMCs began to occur in the renal tissue (60 +/- 6/HP) In the 72 h subgroup of MMC group, and number of BrdU-labeled MMCs, the 96 h subgroup was (143 +/- 8/HP), significantly higher than that of the 72 h subgroup (P0.05).MMCs have the ability to protect renal function in acute renal tubular damage in rats, migrate and repopulate in the I/R injured renal tubules, and inhibits renal tubular epithelial cell apoptosis. The mechanism may be involved in regulating the expression of Bcl-2 and Bax.

To summarize the clinical experience in video-assisted thoracic surgery (VATS).From December 1993 to December 2005 1264 patients, 894 males and 370 females, aged 38.9 +/- 12.0, underwent VATS, including bullectomy in 622 cases, resection of mediastinal tumor or cyst in 119 cases, resection of esophageal diseases in 107 cases, lobectomy or wedge-shaped lung resection in 215 cases, lung volume reduction surgery (LVRS) in 17 cases, treatment of thoracic injury in 28 cases, treatment of other thoracic diseases in 72 cases, and biopsy in 84 cases. For the resection of esophageal carcinoma VATS was conducted via the right approach, the esophagus was dissociated, the lymph nodes were resected, upper-abdominal incision was made, the stomach was dissociated and drawn up to the neck region, a cervical incision was made to anastomose the stomach and the residue of esophagus.Operation was completed by VATS successfully in 1230 patients, and 34 cases were converted to traditional thoracotomy because of thoracic adhesion or to radically treat the malignant tumors. Major complications occurred in 45 cases (3.56%), including air-leak lasting more than 7 days in 30 cases, post-operative bleeding in 4 cases (3 of which received VATS once more for hemostasis and the other underwent thoracotomy), hydrothorax or pneumothorax in 3 cases that underwent water-closed drainage, esophageal mucous rupture in 4 cases with achalasia and one case with leiomyoma, all of which underwent repair immediately, infection of pleural cavity in one case after the resection of esophageal diverticulum, and pneumonia in one case after LVRS. One patient with spontaneous pneumothorax and respiratory failure died 5 days after the bullectomy. Spontaneous pneumothorax occurred in 10 patients 2 months to 2 years after VATS 3 of which underwent bullectomy and pleurodesis by VATS once more.Spontaneous pneumothorax and some benign thoracic diseases are the major indications of VATS; however, great care should be expended to decide to treat malignant diseases by VATS. It is very important to train the surgeons who are to practice VATS. The practice of VATS should be individualized.