[Characteristics and diversity of infectious diarrheal caused by various pathogens]

Objective: To understand the characteristics and differences of diarrhea-related symptoms caused by different pathogens, and the clinical features of various pathogens causing diarrhea. Methods: Etiology surveillance program was conducted among 20 provinces of China from 2010 to 2016. The acute diarrhea outpatients were collected from clinics or hospitals. A questionnaire was used to survey demographics and clinical features. VFeces samples were taken for laboratory detection of 22 common diarrhea pathogens, to detect and analyze the clinical symptom pattern characteristics of the patient's. Results: A total of 38 950 outpatients were enrolled from 20 provinces of China. The positive rates of Rotavirus and Norovirus were the highest among the five diarrhea-causing viruses (Rotavirus: 18.29%, Norovirus: 13.06%). In the isolation and culture of 17 diarrhea-causing bacterial, Escherichia coli showed the highest positive rates (6.25%). The clinical features of bacterial diarrhea and viral diarrhea were mainly reflected in the results of fecal traits and routine examination, but pathogenic Vibrio infection was similar to viral diarrhea. Conclusion: Infectious diarrhea presents different characteristics due to various symptoms which can provide a basis for clinical diagnosis.

Expression of toll-like receptors in hepatic cirrhosis and hepatocellular carcinoma

Toll-like receptors (TLRs) can specifically identify pathogen-associated molecular patterns (PAMPs) by recognizing structural patterns in diverse microbial molecules, and can provide an effective defense against multiple microbial infectious. A variety of TLRs can be expressed on the surface of liver parenchymal as well as nonparenchymal cells. Kupffer cells are a type of hepatic nonparenchymal macrophage, and are positively associated with the severity of liver fibrosis. They play an important role in the synthesis and deposition of the extracellular matrix by upregulating the expression of tissue inhibitor of metalloproteinases and downregulating the activity of matrix metalloproteinases. Cirrhosis, a chronic diffuse lesion usually accompanying extensive liver fibrosis and nodular regeneration, is caused by liver parenchymal cells repeating injury-repair following reconstruction of organizational structure in the hepatic lobules. Hepatocellular carcinoma is caused by repeated and persistent chronic severe liver injury, and partial hepatocytes can eventually transform into hepatoma cells. Multiple TLRs such as TLR2, TLR3, TLR4, and TLR9, as well as other receptors, can be expressed in cirrhosis and hepatocellular carcinoma. About 53 and 85% of hepatocellular carcinoma patients frequently express TLR3 and TLR9, respectively. The chronic and repeated liver injury caused by alcohol, and HBV, HCV, or other pathogens can be recognized by TLRs through the PAMP pathway, which directly increases the risk for hepatic cirrhosis and hepatocellular carcinoma. In this review, we briefly present evidence that the novel cellular molecular mechanisms of TLRs may provide more information about new therapeutics targets of the anti-inflammatory immune response.

Synthesis of Polyhydroxyalkanoate (PHA) from Excess Activated Sludge Under Various Oxidation–Reduction Potentials (ORP) by Using Acetate and Propionate as Carbon Sources

Accumulation of poly hydroxyalkanoate (PHA) from excess activated sludge (EAS) was monitored and controlled via the oxidation-reduction potential (ORP) adjusting process. The ORP was adjusted and controlled by only regulating the gas-flow rate pumped into the cultural broth in which sodium acetate (C2) and propionate (C3) were used as carbon sources. Productivity of PHA and the PHA compositions at various C2 to C3 ratios were also investigated. When ORP was maintained at +30 mV, 35% (w/w) of PHA of cell dry weight obtained when C2 was used as sole carbon source. The PHA copolymer, poly-(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), accumulated by EAS with different 3-hydroxyvalarate (3HV) molar fractions ranged from 8% to 78.0% when C2 and C3 was used as sole carbon source, By using ORP to monitor and control the fermentation process instead DO meter, the ORP system provided more precise control to the PHA accumulation process from EAS under low dissolved oxygen (DO) concentrations. Adjusting the C2 to C3 ratios in the media could control the composition such as the 3HV/3HB ratios of the PHBV. Furthermore, it might be an effective way to adjust the 3HV molar fractions in PHBV by controlling the DO concentration via the ORP monitoring system. The 3HV molar fractions in the PHBV declined with increasing ORP from -30 mV to +100 mV by adjusting the gas-flow rate (i.e. the DO concentration). It is concluded that the DO plays a very important role in the synthesis of 3HV subunits in PHBV co-polymer from the EAS. Therefore, a hypothetic metabolic model for PHA synthesis from EAS was proposed to try to explain the results in this study.

Nutrient release and sediment oxygen demand in a eutrophic land-locked embayment in Hong Kong

Tolo Harbour is a large eutrophic land-locked estuarine embayment in Hong Kong. The rapid urbanization, commercio-industrial activities and lack of legislative control around the Tolo catchment produced large quantities of untreated or partially treated municipal sewage, agricultural wastes and cottage industrial effluents which were discharged into Tolo Harbour via rivers and watercourses. Control measures were implemented to reduce the external nutrient loading into the harbour since the early 1980s. Nutrient data for the period 1982 to 1997 were analyzed for temporal trends. Over the period of observation, the total inorganic nitrogen and total phosphorus both show an increasing trend, despite a decade of efforts in reducing nutrient loading. The release rates of potentially mobile nitrogen (N) and phosphorus (P) from the sediments collected from Tolo Harbour were determined by N and P release experiments under oxic conditions. The experimental results showed that the sediment released significant amount of nutrients, especially orthophosphates and ammonia nitrogen. The maximum release rates were 15.0 and 206.0 mg/m2/day, respectively. Although the external nutrient loading has been reduced, nutrients could gradually be released back into the water column from the contaminated sediments and delay improvement of the water quality.

[Marfan's syndrome with retinal detachment]

14 patients (16 eyes) of Marfan's syndrome are reviewed with regard to retinal detachment. The patients aged a mean 25.1 years; 9 cases were of high myopia, and lens dislocation was found in all. Multiple atrophic retinal holes were detected in 11 eyes (68.8%), and the retina was totally detached in 12 eyes (75.0%). Scleral encircling with external compression performed in 15 eyes achieved retinal reattachment in 14 eyes. The predisposing factors for retinal detachment, the selection of the mode of surgery, the management of the pupil, and the prognosis are discussed.

[Comparative studies on the diagnosis of clonorchiasis by IEST and IFAT]

Both immunoenzymatic staining technique (IEST) and indirect fluorescent antibody test. (IFAT) with frozen sections of adult Clonorchis sinensis as antigen were employed for detecting 51 cases with clonorchiasis and 50 healthy persons. The positive rate was 92% with IEST and 88% with IFAT. The results showed no significant statistic difference (P > 0.05). The false positive rates were 2% with the former and 4% with the latter. When sera from 22 cases with acute schistosomiasis, 20 cases with chronic schistosomiasis and 15 cases with paragonimiasis were examined by IEST and IFAT, cross-reactions were 14%, 5% and 0% with IEST, and 14%, 10% and 0% with IFAT, respectively. The results showed that both IEST and IFAT are useful methods for serological diagnosis of clonorchiasis and the antigen on the gut was well demonstrated, while IEST might be more suitable in field surveys.

[Vitrectomy of vitreal cryoextraction for treatment of intravitreal cysticercosis]

Thirteen (13) patients of intravitreal cysticercosis were treated by vitrectomy (10 patients) or vitreal cryoextraction (3 patients) with successful removal of the parasites. The surgical procedure was described with discussions. Vitrectomy was especially advantageous to late cases of the disease.