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Tong Zhang

Publications and source records attributed to Tong Zhang.

At least 73 records · Page 4Linked to original sources
PubMed2005

[Comparison of the quality and toxicity of wastewater after chlorine and chlorine dioxide disinfections].

The effects of chlorine and chlorine dioxide disinfections on quality and toxicity of wastewater were compared. The experiment results showed that chlorine disinfection had no obvious effect on wastewater color, while chlorine dioxide disinfection decreased wastewater color observably. The DOC of wastewater did not change much after chlorine and chlorine dioxide disinfections. Chlorine disinfection significantly increased UV230 of wastewater and chlorine dioxide disinfection slightly decreased UV230 of wastewater. When the disinfectants dosage was 30 mg/L, UV230 increased about 0.7 cm(-1) after chlorine disinfection and decreased about 0.05 cm(-1) after chlorine dioxide disinfection. The acute toxicity of wastewater increased with increasing disinfectants dosage for both chlorine and chlorine dioxide disinfections and the acute toxicity after chlorine disinfection is much stronger than that after chlorine dioxide disinfection. The genotoxicity of wastewater increased slightly after chlorine disinfection and decreased slightly after chlorine dioxide disinfection.

Chlorine↗
PubMed2004

[Effects of three-stage rehabilitation treatment on acute cerebrovascular diseases: a prospective, randomized, controlled, multicenter study].

OBJECTIVE: To evaluate the effect of tertiary rehabilitation treatment on acute cerebrovascular diseases. METHODS: Fifteen tertiary rehabilitation networks were set up throughout the country. 1078 patients with acute cerebrovascular diseases were randomly divided into 2 groups: rehabilitation group and control group, out of which 19 patients died, 157 dropped out, and 7 successive evaluations were completed in 902 patients that. 439 of the remaining 902 patients in the rehabilitation group, 266 males and 173 females, aged 61 +/- 11, 278 cases with cerebral infarction and 161 with cerebral hemorrhage, received routine treatment and early rehabilitation for 28 days in the ward of neurology, and then went home and received community rehabilitation for 6 months or underwent specialized reinforcement training for 2 months and after that went home and received community rehabilitation for 4 months. The 463 patients in the control group, 281 males and 182 females, aged 60 +/- 11, 291 of which with cerebral infarction and 172 with cerebral hemorrhage, received only routine treatment and early rehabilitation for 28 days in the ward of neurology, and then went home to conduct rehabilitation training by themselves or their family members for 6 months. Evaluation was conducted 7 times, with National Institutes of Health Stroke Scale (NIHSS), Fugl-Meyer motor function scale, Barthel index, SF-36 scale, Lowenstein occupational therapy cognitive assessment (LOTCA), Westen aphasia battery, Hamilton depression scale, and modified Ashworth spasm scale, one week after the onset and by the ends of 1, 2, 3, 4, 5, and 6 months after the onset respectively. RESULTS: The scores of clinical neurological impairment, Fugl-Meyer scores, SF-36 scores, incidence of PSD, and modified Ashworth scores (for upper and lower limbs) were lower, and LOTCA scores and Barthel indexes were higher at different time points in the rehabilitation group than in the control group; and the differences were statistically significant since the 2nd month after the onset. By the end of the 6th month, the patients of the rehabilitation group basically re-achieved the ability of self-care in daily activities with a Barthel index of 84 +/- 33. The patients of the control group also recovered to a certain degree, however, to a smaller extent in comparison with the rehabilitation group. CONCLUSION: Tertiary rehabilitation treatment of cerebrovascular diseases is effective in improving motor function, ability of daily living activities, and quality of life and reducing the incidence rates of secondary complications.

Activities of Daily Living↗
PubMed2004

Acute nerve injury induces long-term potentiation of C-fiber evoked field potentials in spinal dorsal horn of intact rat.

Nerve injury produces a long lasting neuropathic pain, manifested as allodynia, a decrease in pain threshold and hyperalgesia, an increase in response to noxious stimuli. The mechanism underlying the lasting abnormal pain is not well understood. Our previous works have shown that electrical tetanic stimulation of the sciatic nerve induces long-term potentiation (LTP) of C-fiber evoked field potentials in the spinal dorsal horn, which is considered as a synaptic model of pathological pain. In the present study we tested if nerve injury, which is proved to produce neuropathic pain, induced the spinal LTP in intact rats. C-fiber evoked field potentials in spinal dorsal horn produced by electrical stimulation (10-20 V, 0.5 ms, 1/min) of the sciatic nerve were recorded. For induction of LTP of C-fiber evoked field potentials, three types of noxious stimuli were applied. (1) Electrical tetanic stimulation (40 V, 0.5 ms pulses at 100 Hz for 1 s repeated four times at 10 s intervals). (2) Transection of the sciatic nerve at 4-5 mm distal to the stimulation electrode. (3) Crushing the sciatic nerve with a forceps four times at 4-5 mm distal to stimulation electrode (from distal to proximal with 1 mm spacing at 10 s intervals), which simulated electrical tetanic stimulation. Acute nerve injury was made by either transection of the sciatic nerve at the distal to the stimulating electrode or crushing the sciatic nerve. We found that nerve injury by cutting or crushing the sciatic nerve produced LTP of C-fiber evoked field potentials lasting until the end of the experiments (3-9 h), and that pretreatment of the sciatic nerve with lidocaine 10 min prior to the nerve transectoin completely blocked LTP induced by nerve transection. The nerve transection-induced LTP was blocked by NMDA receptor antagonist AP5. LTP produced by nerve transection could not be further potentiated by electrical tetanic stimulation, while LTP induced by single electrical tetanic stimulation could be further potentiated by transection of the sciatic nerve. However, when LTP was saturated by several times of electrical tetanic stimulation, nerve transection did not affect the spinal LTP. We conclude that acute nerve injury induces LTP of C-fiber evoked field potentials in intact animals and that nerve transection is more powerful than electrical tetanic stimulation for induction of the spinal LTP. The results further support the notion that LTP of C-fiber evoked field potentials may underlie neuropathic pain.

Animals↗
PubMed2004

Signaling by higher inositol polyphosphates. Synthesis of bisdiphosphoinositol tetrakisphosphate ("InsP8") is selectively activated by hyperosmotic stress.

Evidence has accumulated that inositol pyrophosphates (diphosphoinositol pentakisphosphate (PP-InsP5) and bisdiphosphoinositol tetrakisphosphate ([PP]2-InsP4)) are intracellular signals that regulate many cellular processes including endocytosis, vesicle trafficking, apoptosis, and DNA repair. Yet, in contrast to the situation with all other second messengers, no one studying multicellular organisms has previously described a stimulus that acutely and specifically elevates cellular levels of PP-InsP5 or [PP]2-InsP4. We now show up to 25-fold elevations in [PP]2-InsP4 levels in animal cells. Importantly, this does not involve classical agonists. Instead, we show that this [PP]2-InsP4 response is a novel consequence of the activation of ERK1/2 and p38MAPalpha/beta kinases by hyperosmotic stress. JNK did not participate in regulating [PP]2-InsP4 levels. Identification of [PP]2-InsP4 as a sensor of hyperosmotic stress opens up a new area of research for studies into the cellular activities of higher inositol phosphates.

Animals↗
PubMed2004

Role of Ca2+/calmodulin-dependent protein kinase II in cardiac hypertrophy and heart failure.

Ca2+/calmodulin-dependent protein kinase II (CaMKII), a critical transducer of Ca2+ signaling, is a multifunctional protein kinase which can phosphorylate a wide range of substrates and regulate numerous cellular functions. The delta isoforms of CaMKII predominate in the heart and two splice variants of CaMKIIdelta, deltaB and deltaC, have been demonstrated to be present in the adult mammalian myocardium. The deltaB isoform contains a nuclear localization signal (NLS) that is absent from deltaC, and consequently, the two isoforms have different subcellular localization. Recent work from our laboratory and others has implicated CaMKII in the development of cardiac hypertrophy and heart failure. The specific roles of these CaMKII isoforms in regulating cardiac function appear to be determined by their subcellular localization. The nuclear deltaB isoform plays a key role in hypertrophic gene expression, whereas the cytoplasmic deltaC isoform can affect excitation-contraction (E-C) coupling through phosphorylation of Ca2+ regulatory proteins and may also transduce signals leading to apoptosis. In addition, the nuclear deltaB and the cytoplasmic deltaC isoforms of CaMKII are differentially regulated in pressure overload-induced cardiac hypertrophy. This review focuses on evidence that CaMKII plays an essential role in transcriptional activation associated with cardiac hypertrophy, as well as the aberrant Ca2+ handling and apoptosis that may contribute to heart failure. The hypothesis that CaMKII isoform selective activation, localization and substrate phosphorylation lead to specificity in the resultant signaling pathways is discussed.

Animals↗
PubMed2004

[A quantitative study of the synaptic alterations in spinal dorsal horn during the induction and maintenance of long-term potentiation].

By using stereological morphometric techniques, we examined the ultrastructure of synapses in lamine II of the spinal dorsal horn of Sprague Dawley rats 30 min, 3 h and 5 h after long-term potentiation (LTP) induction. We found that the numerical density per unit volume (Nv) of total synapses, the thickness of the postsynaptic density (PSD), width of the synaptic cleft increased significantly after the establishment of LTP. (1) Thirty minutes after the formation of LTP, the thickness of the PSD increased from 0.029 +/-0.0064 microm (control) to 0.036 +/-0.009 microm (P<0.05) and the width of the synaptic cleft increased from 0.0181+/-0.0024 microm (control) to 0.0197+/-0.0029 microm (P< 0.05); the number of synaptic vesicles decreased from 0.122 +/-0.011/microm(2) to 0.085 +/-0.010/microm(2) (P<0.05); (2) 3 h after the formation of LTP, the thickness of PSD and the width of the synaptic cleft had no difference compared with those 30 min after LTP. The number of synaptic vesicles increased from 0.122 +/-0.011/microm(2) to 0.138 +/-0.015/microm(2); the curvature of the synaptic interface increased from 1.153+/-0.195 to 1.386 +/-0.311 (P<0.05, compared with control). Nv of negative synapses increased from 0.0187 +/-0.0056 to 0.0543 +/-0.0152 (P<0.05, compared with control), Nv of perforated synapses also increased from 0.0135 +/-0.0053 to 0.0215 +/-0.0076 (P<0.05, compared with control). These data suggest that the increase in thickness of PSD might be the major morphological change during the induction of LTP, while the increase in curvature of the synaptic interface, and the number of perforated synapses might be responsible for the maintenance of the spinal LTP.

Animals↗
PubMed2004

[Role of phospho-calcium/ calmodulin-dependent protein kinase II in the induction and maintenance of long-term potentiation of C-fiber-evoked field potentials in spinal dorsal horn of the rat].

Our previous studies have shown that long-term potentiation (LTP) of C-fiber-evoked field potentials in the spinal dorsal horn is NMDA receptor dependent. It is known that elevation of Ca(2+) in the postsynaptic neurons through NMDA receptor channels during high-frequency stimulation of the afferent fibers is crucial for LTP induction, but how this leads to a prolonged potentiation of synaptic transmission in the spinal dorsal horn is not clear. In the hippocampus, a rise of Ca(2+) activates calcium/calmodulin-dependent protein kinase II (CaMK II) through autophosphorylation. Once this occurs, the kinase remains active, even when Ca(2+) concentration returns to baseline level. Phosphorylated CaMK II potentiates synaptic transmission by enhancement of AMPA receptor channel function via phosphorylation of GluR1 subunit of the receptor and the addition of AMPA receptors to synapses. Up to now, the role of CaMK II in the induction and maintenance of LTP of the C-fiber-evoked field potentials in spinal dorsal horn has not been evaluated. In the present study, we examined the expression of CaMK II and phospho-CaMK II in the lumbar segments (L4-L6) of the rat spinal dorsal horn at 30 min and 3 h after the establishment of LTP induced by tetanic electrical stimulation of the sciatic nerve (40 V, 0.5 ms pulses at 100 Hz for 1 s repeated four times at 10 s intervals) by using Western blot and electrophysiological techniques. To determine the role of the phospho-CaMK II in the induction and maintenance of the spinal LTP, a selective CaMK II inhibitor KN-93 (100 micromol/L) was applied directly onto the spinal cord at the recording segments before and after LTP induction. We found that (1) the protein level of phospho-CaMKII increased at both 30 min and 3 h after LTP induction, while the total protein level of CaMK II increased at 3 h but not at 30 min after LTP induction. (2) Spinal application of KN-93 at 30 min prior to the tetanus blocked both LTP induction and the increase in phospho-CaMK II. (3) 30 min after LTP induction, spinal application of KN-93 depressed LTP and the level of phospho-CaMK II (n=3). (4) Spinal application of KN-93 at 3 h after LTP, however, affected neither the amplitude of the spinal LTP nor the level of phospho-CaMK II in the spinal dorsal horn. These results suggest that activation of CaMK II is probably crucial for the induction and the early-phase maintenance of LTP of C-fiber-evoked field potentials in the spinal dorsal horn.

Animals↗
PubMed2004

Myeloid leukemia with promyelocytic features in transgenic mice expressing hCG-NuMA-RARalpha.

Acute promyelocytic leukemia (APL) is characterized by the accumulation of abnormal promyelocytes in the bone marrow (BM), and by the presence of a reciprocal chromosomal translocation involving retinoic acid receptor alpha (RARalpha). To date, five RARalpha partner genes have been identified in APL. NuMA-RARalpha was identified in a pediatric case of APL carrying a translocation t(11;17)(q13;q21). Using a construct containing the NuMA-RARalpha fusion gene driven by the human cathepsin G promoter (hCG-NuMA-RARalpha), two transgenic mouse lines were generated. Transgenic mice were observed to have a genetic myeloproliferation (increased granulopoiesis in BM) at an early age, and rapidly developed a myeloproliferative disease-like myeloid leukemia. This leukemia was morphologically and immunophenotypically indistinguishable from human APL, with a penetrance of 100%. The phenotype of transgenic mice was consistent with a blockade of neutrophil differentiation. NuMA-RARalpha is therefore sufficient for disease development in this APL model.

Animals↗
PubMed2004

SING: a novel strategy for identifying tumor-specific, CTL-recognized tumor antigens.

Traditional methods for identifying T cell-recognized tumor antigens (Ags) are laborious and time-consuming. In an attempt to simplify the procedure, a novel strategy, SING (SIgnal transduction molecule-mediated, NFAT-controlled, GFP expression) was established as a direct approach for cloning T cell-recognized tumor Ags. In the SING system, a mouse T cell line (BW5147) was transduced with a chimeric H-2Kb construct containing T cell-signaling domains and a green fluorescent protein (GFP) reporter gene under the transcriptional control of nuclear factor of activated T cells (NFAT). The resultant BW5147 cells were named BS cells. This cell line could "sense" TCR stimulation through the T cell-signaling domains after coculture with Ag-specific T cells and then become fluorescent (expressing green fluorescence protein, GFP+) in the presence of Ag peptides. The interaction between BS cells and Ag-specific T cells could be enhanced by addition of costimulatory signals. Currently, BS cells have been optimized to "sense" TCR stimulation after being pulsed with the relevant peptides at concentrations as low as 10(-9) M. Endogenous Ag-expressing BS cells could also become fluorescent after coculture with Ag-specific T cells. Our results provide a proof of principle for using the SING system to directly isolate Ag-expressing BS cells from BS cell repertoires, which are retrovirally transduced with tumor-derived cDNA libraries. Once tumor Ag-marked BS cells are identified, the sequences encoding tumor Ags could be easily retrieved by PCR amplification of the genomic DNA using vector-specific primers.

3T3 Cells↗
PubMed2004

Correlation of Epstein-Barr virus DNA in cell-free plasma, functional imaging and clinical course in locally advanced nasopharyngeal cancer: a pilot study.

BACKGROUND: We evaluated the feasibility of using quantitative real-time polymerase chain reaction (PCR) in monitoring Epstein-Barr virus (EBV) DNA concentrations in cell-free plasma of patients with localized nonmetastatic nasopharyngeal carcinoma (NPC) treated with chemoradiation. METHODS: Cell-free plasma EBV DNA was quantified in six patients with locally advanced, nonmetastatic nasopharyngeal cancer (NPC) who underwent chemoradiation therapy (CRT) and correlated with magnetic resonance imaging (MRI), positron emission tomography (PET) scans, and clinical course. RESULTS: The mean concentration of EBV DNA was 24,610 copies/mL, 682 copies/mL, and 64.5 copies/mL in the pretreatment, posttreatment, and last follow-up samples, respectively. Four of the six patients had normal PET scans and reduction of EBV DNA copy numbers to minimal levels after treatment and, despite equivocal posttreatment MRI scans, are clinically free of recurrent disease. Two of the six patients had elevated EBV DNA copy numbers immediately after treatment, but a metastatic workup was clear at the time; both subsequently relapsed with distant metastases 5 and 11 months later. Although the posttreatment PET scans were abnormal in both of these cases, they were not predictive of the subsequent sites of tumor relapse. CONCLUSIONS: To our knowledge, this is the first report on the correlation between EBV DNA levels and PET scan results in patients with NPC. Reductions in EBV DNA levels and normal PET scans after treatment were consistent among patients who had residual abnormality on MRI images. Persistently elevated EBV DNA levels and abnormal PET scans after treatment suggest residual disease. Further evaluations are required to determine the relative contributions of these two novel techniques in predicting residual disease in locally advanced NPC.

Adult↗
PubMed2004

Quantification of Saccharomyces cerevisiae viability using BacLight.

Yeast viability can be accurately quantified using BacLight, a kit which so far has been used only for bacterial analysis. Upon staining, viable cells can be differentiated from non-viable ones by either confocal laser scanning microscopy (CLSM), epifluorescence microscopy, or flow cytometry. Using Saccharomyces cerevisiae as a model, viabilities quantified by CLSM deviated an average of 1.7% from the actual data, and those determined by flow-cytometry by 1.4%.

Cell Culture Techniques↗
PubMed2004

Transgenic TCR expression: comparison of single chain with full-length receptor constructs for T-cell function.

Genetic modification of T lymphocytes with T-cell receptor (TCR) genes provides a novel tool for adoptive immunotherapy. However, the efficiency of full-length TCR (flTCR)-transduced T cells could be limited by factors such as incorrect pairing between exogenous and endogenous TCR chains and downregulation of the CD3 complex. To overcome these hurdles, one promising strategy is to use three-domain single-chain TCRs (3D-scTCR), in which TCR Valpha and Vbeta chains are joined by a linker with signal transduction domains fused at the carboxyl termini as signal transducers and amplifiers. Our results showed that surface expression of scTCRs on T cells after retroviral transduction was affected by the origin of the transmembrane (TM) region and placement of signaling domains. scTCR-modified T cells were functional as shown by cytokine (IL-2 and IFN-gamma) release in response to antigen stimulation and cytolytic activity against specific target cells. CD8 and CD28, but not the complete CD3 complex, could enhance the scTCR-induced T cell activation. Compared with flTCR-modified T cells and native CTLs, scTCR-modified T cells require higher thresholds of antigen stimulation (approximately 10(-8) M peptide) to be functional. Despite the low efficiency of scTCRs, our data provide insight into further improvements in generating efficient scTCRs for in vivo applications.

Animals↗
PubMed2004

Cardiomyocyte calcium and calcium/calmodulin-dependent protein kinase II: friends or foes?

Calcium (Ca(2+)) is a critical second messenger in cell signaling. Elevated intracellular Ca(2+) can activate numerous Ca(2+)-regulated enzymes. These enzymes have different subcellular localizations and may respond to distinct modes of Ca(2+) mobilization. In cardiac muscle, Ca(2+) plays a central role in regulating contractility, gene expression, hypertrophy, and apoptosis. Many cellular responses to Ca(2+) signals are mediated by Ca(2+)/calmodulin-dependent enzymes, among which is the Ca(2+)/calmodulin-dependent protein kinase II (CaMKII). Putative substrates for CaMKII include proteins involved in regulating Ca(2+) storage and release, transcription factors, and ion channels. The major isoform of CaMKII in the heart is CaMKIIdelta. Two cardiac splice variants, CaMKIIdelta(B) and delta(C), differ in whether they contain a nuclear localization sequence. Our laboratory has examined the hypothesis that the nuclear delta(B) and the cytoplasmic delta(C) isoforms respond to different Ca(2+) stimuli and have distinct effects on hypertrophic cardiac growth and Ca(2+) handling. We have shown that pressure overload-induced hypertrophy differentially affects the nuclear delta(B) and the cytoplasmic delta(C) isoforms of CaMKII. Additionally, using isolated myocytes and transgenic mouse models, we demonstrated that the nuclear CaMKIIdelta(B) isoform plays a key role in cardiac gene expression associated with cardiac hypertrophy. The cytoplasmic CaMKIIdelta(C) isoform phosphorylates substrates involved in Ca(2+) handling. Dysregulation of intracellular Ca(2+) and resulting changes in excitation-contraction coupling characterize heart failure and can be induced by in vivo overexpression of CaMKIIdelta(C) and phosphorylation of its substrates. The differential location of CaMKII isoforms and their relative activation by physiological vs. pathological stimuli may provide a paradigm for exploring and elucidating how Ca(2+)/CaMKII pathways can serve as both friends and foes in the heart.

Animals↗
PubMed2004

Epstein-Barr virus DNA measured in nasopharyngeal brushings in patients with nasopharyngeal carcinoma: pilot study.

OBJECTIVE: We measured the amount of tumour-derived Epstein-Barr virus (EBV) deoxyribonucleic acid (DNA) in the nasal brushings of nasopharyngeal carcinoma (NPC) patients to determine the correlation with tumour load and response to treatment. MATERIALS AND METHODS: Twenty-eight patients with NPC were included in the study. Baseline measurements of EBV from nasopharyngeal brushings were obtained from 26 patients prior to treatment. A follow-up sample was available from 11 of these patients post-treatment and from 2 additional patients who did not have a baseline sample. Quantitative real-time polymerase chain reaction (PCR) using SYBR Green I fluorescent dye was used to detect the EBV DNA copy number. RESULTS: Nasopharyngeal brush biopsies showed a high copy number of EBV DNA in most of the pretreatment samples (median 9714 copies/mL). The highest copy number detected was 14536944 copies/mL in one sample. In the post-treatment follow-up samples, the copy number was significantly lower (median 6 copies/mL). CONCLUSIONS: We have demonstrated that EBV DNA can be detected in the brush biopsies from NPC patients using quantitative real-time PCR. These pilot data suggest that nasopharyngeal brushings with PCR detection of EBV may be an effective tool for determining local tumour response. The potential of this technique as an NPC tumour marker for post-treatment follow-up is being validated with larger patient numbers.

Adult↗
PubMed2004

[Le Fort III osteotomy and medium position distraction for mid-facial hypoplasia].

OBJECTIVE: To probe the possibility of distraction osteogenesis for correction of mid-facial hypplasia using a new technique. METHODS: The distraction system of mid-facial skeleton consisted of a face-bow, the elastic loops and a device that hitched to bone holes made in the aperture rim. Flllowing Le Fort III osteotomy, a bone hole was drilled at each side of the external-inferior rim of the aperture by a dental bur. The traction device was hitched to the holes through the nostrils. Distraction began three days postoperatively, with the force adjusted dependently upon the rate of progress. When the skeleton reached to the planed position, distraction was retained with a minor force for 8 weeks. Three adults with mid-facial hypoplasia underwent this treatment. RESULTS: The mid-facial skeleton showed a balanced advancement. The patients' facial contour and occlusal relationship recovered completely. CONCLUSIONS: Patients with severe mid-facial hypoplasia could be corrected ideally by the new technique, with balanced advancement of mid-facial skeleton, minor trauma. The design of distraction system was reasonable. The manipulation of the procedure was easy.

Adult↗
PubMed2004

Degradation of phenol in an upflow anaerobic sludge blanket (UASB) reactor at ambient temperature.

A synthetic wastewater containing phenol as sole substrate was treated in a 2.8 L upflow anaerobic sludge blanket (UASB) reactor at ambient temperature. The operation conditions and phenol removal efficiency were discussed, microbial population in the UASB sludge was identified based on DNA cloning, and pathway of anaerobic phenol degradation was proposed. Phenol in wastewater was degraded in an UASB reactor at loading rate up to 18 gCOD/(L x d), with a 1:1 recycle ratio, at 26 +/- 1 degrees C, pH 7.0-7.5. An UASB reactor was able to remove 99% of phenol up to 1226 mg/L in wastewater with 24 h of hydraulic retention time (HRT). For HRT below 24 h, phenol degradation efficiency decreased with HRT, from 95.4% at 16 h to 93.8% at 12 h. It further deteriorated to 88.5% when HRT reached 8 h. When the concentration of influent phenol of the reactor was 1260 mg/L (corresponding COD 3000 mg/L), with the HRT decreasing (from 40 h to 4 h, corresponding COD loading increasing), the biomass yields tended to increase from 0.265 to 3.08 g/(L x d). While at 12 h of HRT, the biomass yield was lower. When HRT was 12 h, the methane yield was 0.308 L/(gCOD removed), which was the highest. Throughout the study, phenol was the sole organic substrate. The effluent contained only residual phenol without any detectable intermediates, such as benzoate, 4-hydrobenzoate or volatile fatty acids (VFAs). Based on DNA cloning analysis, the sludge was composed of five groups of microorganisms. Desulfotomaculum and Clostridium were likely responsible for the conversion of phenol to benzoate, which was further degraded by Syntrophus to acetate and H2/CO2. Methanogens lastly converted acetate and H2/CO2 to methane. The role of epsilon-Proteobacteria was, however, unsure.

Bacteria, Anaerobic↗
PubMed2004

[An evaluation of effects of intervention on maternal and child health in the rural areas of China].

OBJECTIVE: To evaluate the impact of training maternal and child health care providers in the rural areas of China on improvement of health care to pregnant and puerperal women. METHODS: The data originated from the Reproductive Health/Family Planning Project implemented by the State Family Planning Commission and the Ministry of Health from 1998 to 2002, which covered 32 counties in 22 provinces of China. A quasi-experimental design was used. 6 counties were selected from 32 project counties as the intervention group, while 6 non-project counties were taken as the control group with the condition similar to that of the selected project counties in respect to their number of population and economic level. The subjects of the study were mothers with child under 3 years. A total of 348 mothers were interviewed using a structured questionnaire by strictly trained surveyors. It was focused on prenatal care and postpartum follow-up in the survey. INTERVENTION: According to the plan of the project, all maternal and child health care providers at the grass-root level were given a 2-week theoretical training, and some of them were assigned to hospitals where they were gievn a 1-month clinical skills training. RESULTS: With regard to prenatal care, the mothers in intervention group received more prenatal care than those in control group (mean number of obstetric visits: 6.64 vs 5.64, P<0.05). The number of items of examination taken in intervention group was more than that in control group (6.71 versus 5.67, P<0.05). The proportion of the mothers in intervention group who were told that they must visit doctors if they felt uncomfortable in pregnant period, was higher than that in control group (P<0.05). 8 symptoms or signs that possibly occur in pregnant period were listed; in this connection, the mothers in intervention group knew more than those in control group (3.43 vs 2.09, P<0.05). In the postpartum follow-up, more mothers in the intervention group were examined by the doctors. The proportion of mothers who were informed of contraceptive methods was higher in intervention group than in control group (94% vs 78.5%, P<0.05). The descending rate of maternal mortality rate in the intervention areas was much higher than that in the control areas. CONCLUSION: The training of maternal and child health care providers had a significant impact on improving their service skills and quality; consequently, the women covered by their service could receive better maternal and child health care. This indicates that the Reproductive Health/Family Planning Project implemented in the rural areas of China is successful.

Adult↗