共查询到20条相似文献,搜索用时 15 毫秒
1.
Fernández-Delgado M Contreras M García-Amado MA Gueneau P Suárez P 《Revista do Instituto de Medicina Tropical de S?o Paulo》2007,49(6):355-359
The fecal contamination of raw seafood by indicators and opportunistic pathogenic microorganisms represents a public health concern. The objective of this study was to investigate the presence of enteric bacteria colonizing oysters collected from a Venezuelan touristic area. Oyster samples were collected at the northwestern coast of Venezuela and local salinity, pH, temperature, and dissolved oxygen of seawater were recorded. Total and fecal coliforms were measured for the assessment of the microbiological quality of water and oysters, using the Multiple Tube Fermentation technique. Analyses were made using cultures and 16S rRNA gene sequencing. Diverse enrichment and selective culture methods were used to isolate enteric bacteria. We obtained pure cultures of Gram-negative straight rods with fimbriae from Isognomon alatus and Crassostrea rhizophorae. Our results show that P. mirabilis was predominant under our culture conditions. We confirmed the identity of the cultures by biochemical tests, 16S rRNA gene sequencing, and data analysis. Other enterobacteria such as Escherichia coli, Morganella morganii and Klebsiella pneumoniae were also isolated from seawater and oysters. The presence of pathogenic bacteria in oysters could have serious epidemiological implications and a potential human health risk associated with consumption of raw seafood. 相似文献
2.
Invasion of toxic marine cyanobacteria in to the tsunami affected coastal villages of southern India
Muthukumaravel S Padmanabhan V Boopathidoss PS Sadanandane C Srinivasan R Gunasekaran K Sabesan S Balaraman K 《The Journal of communicable diseases》2010,42(2):135-138
This documentation explores the facts about the invasion of marine cyanobacteria in to the tsunami affected coastal villages of Nagapattinam district of Tamilnadu and Karaikkal district of Pondicherry Union Territory (UT) in southern India. Water samples were collected from eight tsunami-hit coastal villages in different open water sources. The collected samples were processed for detecting marine cyanobacterial growth. Totally 110 water samples were processed, three samples were positive for the toxic cyanobacteria, Lyngbya sp., and nine for nontoxic species such as Epithemia sp.,, Johannesbaptistia pellucida, Oscillatoria princeps, Phormidium fragile, Synechocystis sp. Besides posing a public health risk because of the toxic cyanobacteria, the bloom formation by the cyanobacterial species such as Anabaena, Microcystis, Lyngbya, Plectonema, Phormidium contaminated the water bodies and deteriorated the water quality in the tsunami affected villages. The study revealed that another kind of public health risk from the invasion of toxic cyanobacteria to the costal ecosystem during the tsunami. It is necessary, in this context, that the surveillance mechanism, which is geared up during or after natural disasters, should have a provision to monitor the transportation of toxic elements/organisms from marine system to coastal/inland ecosystems and to control such organisms. 相似文献
3.
目的掌握安阳市农村饮用水高砷水源分布,为地方性砷中毒防治提供科学依据。方法根据既往调查资料,在全市重点乡村进行饮水砷含量调查,水砷测定采用原子荧光光度法。结果在全市5个县(市)32个乡(镇)77个自然村采集水样1584份,水砷超标率1.33%(21/1584);发现滑县的9个村饮水砷含量超标,高砷水源呈灶状分布,高砷暴露人口8475人。结论在安阳市首次发现存在高砷水源,今后应继续开展高砷水源筛查和病情调查。 相似文献
4.
饮水型砷中毒病区居民血清尿素氮浓度检测分析 总被引:1,自引:0,他引:1
目的探讨饮用高砷水对机体尿素氮水平的影响。方法以2个地区(高砷区和对照区)的常住成年居民为调查对象,采集晨尿及空腹静脉血,同时采集受访者家中饮用水水样。用原子吸收法测水总砷,用苦味酸比色法检测尿肌酐,采用酶偶联速率法测尿素氮。结果饮水型砷中毒病区居民血清尿素氮平均水平(5.08 mmol/L)高于非高砷区居民(3.60 mmol/L),二者差异显著(P=0.0239);饮水型砷中毒病区居民饮用水总砷浓度与血清尿素氮水平呈正相关关系(r=0.293,P=0.023)。结论饮用高砷水对居民肾脏存在潜在危害。 相似文献
5.
Yigitler C Gulec B Aydogan H Ozcan A Kilinc M Yigit T Kozak O Pekcan M 《Journal of gastroenterology and hepatology》2004,19(10):1179-1186
BACKGROUND AND AIM: In inflammatory bowel disease it has been established that enteric microorganisms are present in the final stage of the active inflammatory process. The purpose of the present study was to investigate the effects of mesalazine, and metronidazole-gentamicin combination, on bacterial translocation in an animal colitis model. METHODS: Fifty rats were stratified into five groups. The control group (group NC) was given only 2 mL saline enema and the remaining four groups were given 2 mL acetic acid enema. Group CC was the diseased control group. The treatment regimens started on the fifth day: mesalazine enema in group MesC, metronidazole-gentamicin in group MGC, and mesalazine + metronidazole + gentamicin in group MesMGC. After death on day 10, 2.5-cm colonic segments from all groups were weighed separately. In all rats, histopathological scoring was done, and samples from feces, blood, liver and spleen underwent microbiological analyses. RESULTS: For all diseased rats, both mean weight loss and colonic segment weight/bodyweight ratio was significantly higher than that in the sham group. As compared with other groups, body and colonic segment changes as well as histopathological scoring in rats receiving mesalazine enema either solely or in combination with the antibiotics were lower. No bacterial growth was found in the blood, liver and spleen of the rats in the control group while enteric bacteria, mainly Escherichia coli (35%) were the most common bacteria translocated to that in the latter. Antibiotic combination, alone or in combination with mesalazine was effective in reducing the bacterial translocation while mesalazine administration did not properly influence its regression. CONCLUSIONS: Gram-negative enteric bacteria, predominantly E. coli, was the most common bacteria isolated in bacterial translocation occurring in acetic acid-induced colitis. This trial showed that mesalazine alone did not incorporate the reduction of infectious events, despite its beneficial effect on inflammatory changes in experimental colitis. Metronidazole and gentamicin combination given intraperitoneally was more effective than topical mesalazine in decreasing bacterial translocation. 相似文献
6.
目的掌握郑州市居民饮水砷状况以及是否存在地方性砷中毒。方法根据饮水型地方性砷中毒分布规律,在全市重点地区选择调查点进行饮水砷测定及砷中毒情况调查。结果全市6个县(市)34个乡(镇)286个自然村共采集测定水样622份,水砷在0—0.1860mg/L之间。首次在位于郑州市东部平原地区的中牟县检测出高砷水井6眼,水砷最高为0.1860mg/L,最低为0.056mg/L,高砷水埋深26—40m。其他县(市)水砷均在0.05mg/L以下,全部在国家规定标准以内。在对水砷超标的重点乡走访调查中,未发现砷中毒病人。结论郑州市存在高砷地区,但是尚未发现地方性砷中毒的流行。 相似文献
7.
Lasheras A Boulestreau H Rogues AM Ohayon-Courtes C Labadie JC Gachie JP 《American journal of infection control》2006,34(8):520-525
The reservoir for hospital-acquired Legionnaires' disease has been shown to be the potable water distribution system. The objectives of the present study were as follows: (1) to examine the possible relationship between physical-chemical characteristics of water such as temperature, pH, hardness, conductivity, and residual chlorine and the presence of amoebae as growth-promoting factors for Legionella species and (2) to determine eradication measures for water distribution systems to seek ways of reducing the risk of legionellosis. Ten hospitals in southwest France took part in this study. Water samples were collected from 106 hot water faucets, showers, hot water tanks, and cooling towers. Two analyses were performed to analyze the association between water characteristics and (1) the presence of Legionella species and (2) the proliferation of Legionella species. Of the 106 water samples examined, 67 (63.2%) were positive for Legionella species. Amoebae were detected in 73 of 106 (68.9%) samples and in 56 of 67 (86.6%) Legionella species-positive samples (P < 10(-6)). In these positive samples, conductivity was lower than 500 microOmega(-1).cm(-1) in 58.2% (P = .026), temperature was below 50 degrees C in 80.6% (P = .004), and hardness was significantly higher (P = 002) than in Legionella species-negative samples. Neither Legionella species nor amoebae were isolated from any sampling point in which the water temperature was above 58.8 degrees C. Multivariate analysis shows that high hardness and presence of amoebae were strongly correlated statistically with the presence of Legionella when showers, tanks, pH, and temperature promoted their proliferation. This study shows the importance of water quality evaluation in assessing environmental risk factors and in selecting the most appropriate prevention and control measures in hospital water systems. 相似文献
8.
W. Abu Al-Soud U. Stenram . Ljungh K.-G. Tranberg H.-O. Nilsson T. Wadstrm 《Digestive and liver disease》2008,40(2):126-131
BACKGROUND AND AIM: Gastric and enteric Helicobacter species have been associated with the pathogenesis of some extragastric diseases. METHODS: We retrospectively investigated the presence of DNA of Helicobacter species in samples of the cancer and the surrounding tumour-free liver tissues of patients with hepatocellular carcinoma (HCC, n=12) and cholangiocarcinoma (CC, n=13). The patients were from an area with low liver cancer incidence and with low hepatitis B and C prevalence. Patients with a benign liver disease (n=24) were included as controls. Paraffin-embedded liver samples were examined by a Helicobacter genus-specific PCR assay as well as group-specific PCR assays for Enterobacteriaceae, Bacteroides, Lactobacillus and Enterococcus. PCR products of positive samples were characterised by denaturing gradient gel electrophoresis (DGGE) and DNA sequencing. RESULTS: PCR assay detected Helicobacter DNA in seven of 12 (58%) and eight of 13 (62%) normal liver tissue specimens from HCC and CC patients, respectively. Two cancer samples from HCC patients were Helicobacter-positive but none of the CC cancers. In the control group, three of 24 (12.5%) patients with a benign liver condition were positive for Helicobacter species (p<0.01 compared to results of tumour-free liver tissue from the cancer patients). DGGE and DNA sequence analysis showed that 90% of the detected PCR products were "H. pylori-like". DNA of some other enteric bacteria was detected in the liver of one cancer patient and one control (4% of all patients). CONCLUSION: The presence of DNA of Helicobacter species in liver specimens, but not of other common gut bacteria, was associated with human hepatic carcinogenesis. 相似文献
9.
Wongworapat K Keawvichit R Putsyanant P Khantawa B Silprasert A Karnchanawong S 《The Southeast Asian journal of tropical medicine and public health》2001,32(Z2):236-239
An attempt to use treated wastewater for agriculture in the Chiang Mai area was made, but the re-use process had to be performed under a condition that limited the risks liable to leave pathogens present in the water. The objective of our study was to examine the intestinal parasites and enteric bacteria in the wastewater and treated wastewater from the Chiang Mai University campus as well as the treated wastewater from the Chiang Mai municipality. The raw wastewater (RW), primary treatment effluent water (PE), treated wastewater using the activated sludge system (AS) from the Chiang Mai University campus and treated wastewater using the aerated lagoon (AL) system from the Chiang Mai municipality were examined for intestinal parasites and enteric bacteria by using the centrifugal sedimentation and conventional methods respectively. The ground water (GW) and the irrigation water (IW) were used for comparison. All kinds of water were collected and examined twice a month for 6 months (February to July 2000). None of human intestinal parasites were found from any wastewater, whereas the RW and PE water contained hookworm larva, Ascaris egg and Taenia egg on some occasions. A small amounts of pathogenic bacteria that can cause severe diarrhea were detected. Salmonella enteritidis gr E was isolated from the AL water in April, while Vibrio cholerae type O139 was detected from the PE water in June. Some pathogenic bacteria that might cause gastroenteritis, such as Aerobacter spp, Citrobacter spp, Pseudomonas spp and Escherichia coli were also found in all kinds of water. Between the two types of treated wastewater, the bacteria found in AS water was less than that in AL water in terms of both amount and type of bacteria. The treated wastewater from the city of Chiang Mai, compared to natural water such as irrigation water, appears to be safe to use for agriculture. 相似文献
10.
Methane contamination of drinking water accompanying gas-well drilling and hydraulic fracturing 总被引:10,自引:0,他引:10
Osborn SG Vengosh A Warner NR Jackson RB 《Proceedings of the National Academy of Sciences of the United States of America》2011,108(20):8172-8176
Directional drilling and hydraulic-fracturing technologies are dramatically increasing natural-gas extraction. In aquifers overlying the Marcellus and Utica shale formations of northeastern Pennsylvania and upstate New York, we document systematic evidence for methane contamination of drinking water associated with shale-gas extraction. In active gas-extraction areas (one or more gas wells within 1 km), average and maximum methane concentrations in drinking-water wells increased with proximity to the nearest gas well and were 19.2 and 64 mg CH(4) L(-1) (n = 26), a potential explosion hazard; in contrast, dissolved methane samples in neighboring nonextraction sites (no gas wells within 1 km) within similar geologic formations and hydrogeologic regimes averaged only 1.1 mg L(-1) (P < 0.05; n = 34). Average δ(13)C-CH(4) values of dissolved methane in shallow groundwater were significantly less negative for active than for nonactive sites (-37 ± 7‰ and -54 ± 11‰, respectively; P < 0.0001). These δ(13)C-CH(4) data, coupled with the ratios of methane-to-higher-chain hydrocarbons, and δ(2)H-CH(4) values, are consistent with deeper thermogenic methane sources such as the Marcellus and Utica shales at the active sites and matched gas geochemistry from gas wells nearby. In contrast, lower-concentration samples from shallow groundwater at nonactive sites had isotopic signatures reflecting a more biogenic or mixed biogenic/thermogenic methane source. We found no evidence for contamination of drinking-water samples with deep saline brines or fracturing fluids. We conclude that greater stewardship, data, and-possibly-regulation are needed to ensure the sustainable future of shale-gas extraction and to improve public confidence in its use. 相似文献
11.
Anderson AD Heryford AG Sarisky JP Higgins C Monroe SS Beard RS Newport CM Cashdollar JL Fout GS Robbins DE Seys SA Musgrave KJ Medus C Vinjé J Bresee JS Mainzer HM Glass RI 《The Journal of infectious diseases》2003,187(2):303-306
In February 2001, episodes of acute gastroenteritis were reported to the Wyoming Department of Health from persons who had recently vacationed at a snowmobile lodge in Wyoming. A retrospective cohort study found a significant association between water consumption and illness, and testing identified Norwalk-like virus (NLV) in 8 of 13 stool samples and 1 well. Nucleotide sequences from the positive well-water specimen and 6 of the positive stool samples were identical. This multistrain NLV outbreak investigation illustrates the importance of NLV as a cause of waterborne illness and should encourage monitoring for NLVs in drinking water. 相似文献
12.
Quality of potable water and incidence of gastroenteritis in 2 cities in the state of Sonora, Mexico
Based on the fact that drinking-water is of great significance in the transmission of infectious diseases, the incidence of diarrheal disorders was examined in two cities similar in their demographic composition and in their use of health services, but not in the quality of the drinking-water supply. In Navojoa, a city with high incidence of diarrheal diseases (116/1000 pop. in 1985), high rates of drinking-water contamination with fecal coliforms were found (43% of water samples); on the contrary, in Ciudad Obregón, a city with lower rates of diarrheal diseases (49/1000 pop. in 1985), drinking-water contamination with fecal coliforms was also comparatively lower (only 6% of water samples). These data illustrate the need to promote the implementation of drinking-water treatment in those places with signs of fecal contamination and high incidence of diarrheal diseases. To this regard, the General Direction for Research and Technological Development of the Ministry of Health has promoted the development of a chlorination equipment, useful mainly in rural areas, where biological contamination is usually high. These and similar procedures for water treatment should be considered as effective means to decrease the incidence of diarrheal diseases. 相似文献
13.
T Szumilas Z Sobol 《Bulletin of the Institute of Maritime and Tropical Medicine in Gdynia》1990,41(1-4):157-166
The study presents the results of physical-chemical examinations of the coastal water of the Baltic Sea, carried out from 1984-1988 on 18 sampling stations located in the region of Gdynia and Gdańsk, and along the Hel Peninsula. The samples were collected weekly from the surface of water in the distance of about 5 m from the shore during 5 years. The results indicated a considerable physical and chemical pollution of the coastal water of Gdańsk Bay. Noted is the absence of the criteria of sanitary evaluation of the sea water regarding its usability for recreation. Mean concentration values of phosphates, ammonia compounds and nitrites as well as BOD5 in the coastal water of Gdańsk Bay were on the average 5-10 times higher than in the water of the open Baltic Sea. If the level of reference is the open sea water, it must be assumed that the coastal water of the Gdańsk Bay is strongly polluted. Useful seems to be the determination of the level of the physical and chemical pollution of the sea coastal water by comparison of certain indices with the values characteristic for open, clean sea or by relating them to the values making the "background" for the sea area examined. There is a need to elaborate evaluation criteria of physical and chemical pollution of sea coastal waters. 相似文献
14.
Awolola TS Oduola AO Obansa JB Chukwurar NJ Unyimadu JP 《Journal of vector borne diseases》2007,44(4):241-244
BACKGROUND & OBJECTIVE: Urban malaria is on the rise in Nigeria due to rapid industrialisation and developmental activities. A study was undertaken in Lagos, Nigeria to study the Anopheles breeding in polluted water bodies. METHODS: Anopheles larval breeding habitats were surveyed and water samples from 24 larval breeding sites from four strategic areas in urban Lagos were analysed. The relationship between eight abiotic variables (pH, dissolved oxygen, conductivity, hardness, nitrate, total dissolved solids, turbidity and oil) and density of Anopheles larvae were investigated. The levels of heavy metals (Zn, Co, Cu, Pb, Mn, Fe, Hg and Ni) pollution were analysed by Atomic Absorption Spectrophotometry. RESULTS: Morphological and PCR analysis of 2358 anopheline larvae revealed only the presence of two members of the Anopheles gambiae complex consisting of 93.1% Anopheles gambiae s.s. and 6.9% An. arabiensis. Multiple regression analysis revealed a significant association between occurrence of An. arabiensis larvae and two independent variables: pH and turbidity but not for An. gambiae s.s. The levels of three heavy metals: Fe, Cu and Pb from more than half of the sites surveyed were three times higher than the values obtained in natural breeding sites of An. gambiae s.s. from a rural area of Lagos. Over 85% of An. gambiae s.s. larvae were found in water bodies characterised by low dissolved oxygen (<3 mg/L), high conductivity (>900 uS/cm), turbidity (>180 FAU), oil (>11 mg/L) and heavy metals: Fe, Cu, and Pb (>0.4 mg/L). INTERPRETATION & CONCLUSION: These results indicate that An. gambiae s.s. is adapting to a wide range of water pollution in this urban area. The survival of the mosquito in widespread polluted water bodies across Lagos metropolis could be responsible for the rise in the incidence of malaria. 相似文献
15.
Toshihiro Nukiwa 《Respiratory investigation》2012,50(4):124-128
A 9.0-magnitude earthquake, with an epicenter 150 km east of the Tohoku area of Japan in the deep Pacific Ocean, triggered an unexpectedly huge tsunami and caused 19,000 casualties along 500 km of the Pacific coast in northern Japan, as documented by Ozawa et al. [1]. This brief review provides an overview of the tsunami disaster and ensuing respiratory medical conditions, from emergency rescue conditions to chronic stage diseases, leading to a series of reviews, original articles, and case reports. Successive mega-earthquakes in the previous decade around the world may suggest a shift in the Earth's geological state from the stable to the active stage. The “tsunami lung” term is not limited to the near-drowning lung; inhalation of the sandy wave or of the sludge and slime near industrialized areas can cause inflammation and rare semi-acute phase fungal infections. Although the long-term outcomes of tsunami-related respiratory medicine need further analysis, determining how to reduce the extent of damage is a critical and central issue. 相似文献
16.
目的了解河南省饮水型氟中毒病区病情现状,为防治工作提供科学依据。方法按照《河南省2010年地方病防治项目技术方案》要求,在饮水型氟中毒病区抽取10个县(区),在每个县(区)随机抽取10个降氟改水工程,采用分层抽样方法按照轻、中、重原则随机抽取3个病区村。进行水氟含量及8~12岁儿童氟斑牙患病情况监测。结果在10个县(区)共监测100个降氟改水工程,99个能正常运行,改水工程水氟含量超标率21%(21/100)。共调查30个病区村,其中8个为已改水病区村,降氟改水工程水氟含量全部合格,8~12岁儿童氟斑牙的总检出率52.71%(496/941),缺损率5.84%(55/941),氟斑牙指数1.19,流行强度中等;22个为未改水病区村,8~12岁儿童氟斑牙检出率为47.34%(1015/2144),缺损型氟斑牙检出率为13.29%(285/2144),氟斑牙指数为1.15,流行强度中等。结论河南省改水工程水氟含量超标现象依然严重,氟中毒危害仍然较重。因此,应加强改水工程建设的科学论证和竣工时工程验收,杜绝不合格工程投入使用;坚持定期开展水质监测,对水质超标工程及时进行整改。 相似文献
17.
Szewzyk U Szewzyk R Stenström TA 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(5):1810-1813
A borehole drilled to a total depth of 6779 m in granitic rock in Gravberg, Sweden, was sampled and examined for the presence of anaerobic, thermophilic, fermenting bacteria and sulfate-reducing bacteria. Growth in enrichment cultures was obtained only from water samples collected from a specific sampling depth in the borehole (3500 m). The hole was cased down to a depth of 5278 m and open to the formation below that level. All the water below 2000 m in depth standing in the borehole at the time of sampling must have entered at the 5278-m level or below, during a prior pumping operation. A strong salinity stratification certifies that no major amount of vertical mixing had taken place. The depth from which bacteria could be enriched was that of a pronounced local minimum of salinity. Pure cultures of thermophilic, anaerobic, fermenting bacteria were obtained with the following substrates: glucose, starch, xylan, ethanol, and lactate. The morphology and physiology of the glucose- and starch-degrading strains indicate a relationship to Thermoanaerobacter and Thermoanaerobium species. All but one of the newly isolated strains differ however from those by lacking acetate as a fermentation product. The glucose-degrading strain Gluc1 is phylogenetically related to Clostridium thermohydrosulfuricum, with an evolutionary distance based upon rRNA sequence comparisons of 3%. No sulfate-reducing or methanogenic bacteria were found. 相似文献
18.
19.
北京地区肠道致病菌的分布及耐药状况 总被引:24,自引:1,他引:24
目的 监测北京地区肠道致病菌的组成及耐药状况,为本地区的流行病学研究及临床合理用药提供依据。方法 通过常规大便培养,筛选出致病菌后经生化及血清学进一步鉴定到种,群或血清型。结果 肠道病原菌感染,以男性为主,儿童和青年发病为多,6,7月为腹泻发病高峰,病原以志贺菌属居首位,其次是弧菌,各菌属对抗生素的敏感率有差异。结论 北京地区感染性腹泻的病原种类繁多,有性别,年龄,季节的分布特点,耐药性不同,应重视监测。 相似文献
20.
Dr. Frank G. Moody MD Diane Haley-Russell PhD Debra M. Muncy MD 《Digestive diseases and sciences》1995,40(8):1798-1804
Pancreatic infection from gut-derived bacteria has emerged as the major cause of death in necrotizing pancreatitis. Bacterial overgrowth of indigenous enteric organisms as a consequence of gut stasis (ileus) represents a potential initial event in this process. The present study was designed to examine the interrelationships between intestinal transit, enteric bacteriology, and the translocation of bacteria from the gut lumen to mesenteric lymph nodes and splanchnic viscera during experimentally induced acute pancreatitis. Male rats underwent pancreaticobiliary duct ligation (PBDL) or sham surgery and were sacrificed after 24, 48, or 96 hr. Severity of pancreatitis was assessed with histology, tissue water content, and amylase and lipase levels. Intestinal transit was measured with fluorescent tracers. Blood, mesenteric lymph nodes (MLNs), splanchnic organs, and gut luminal contents were subjected to bacteriologic analysis. PBDL was followed by biochemical and histologic evidence of progressive pancreatic injury at each time interval. Enteric bacteria within the gut and in adjacent MLNs increased as intestinal transit decreased after PBDL-induced pancreatic inflammation. Surprisingly, all parameters returned to control levels by 96 hr in spite of progression of pancreatic inflammation. 相似文献