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Early detection of human papillomavirus (HPV) is important for the clinical diagnosis of cervical cancer. However, to date, the pathogenesis of cervical cancer is still unclear. Autophagy is a dynamic process that contributes to the maintenance of cellular homeostasis. Here, we investigate whether variants of autophagy genes affect the occurrence of cervical cancer. In this study, our results indicate that single nucleotide polymorphisms (SNPs) of autophagy‑related protein 4 (ATG4), including rs4036579, rs5973822, rs807181, rs807182 and rs807183, have a significant relationship with cervical cancer risk. Furthermore, stratified analysis suggests that the homozygous variant genotype could decrease the risk of cervical cancer and should be considered when investigating the role of HPV in cervical cancer. We aim to investigate whether SNPs of ATG4A contribute to HPV infection in the population of Southwestern China. The association of both single SNPs and SNP‑SNP interactions with HPV was evaluated in a sample of cancer cases and healthy control subjects. The interaction of rs807181 and rs807183 was associated with HPV infection in case and control subjects (combined P=2.00x10‑3 and 3.22x10‑2, respectively). This result showed that ATG4A SNP interactions may affect HPV infection in the population of Southwestern China. Notably, the autophagy gene ATG4A may contribute to cervical cancer. [ABSTRACT FROM AUTHOR]

While adriamycin (adr) offers improvement in survival for breast cancer (BCa) patients, unfortunately, drug resistance is almost inevitable. Mounting evidence suggests that exosomes act as a vehicle for genetic cargo and constantly shuttle biologically active molecules including microRNAs (miRNAs) between heterogeneous populations of tumor cells, engendering a resistance-promoting niche for cancer progression. Our recent study showed that exosomes from docetaxel-resistance BCa cells could modulate chemosensitivity by delivering miRNAs. Herein, we expand on our previous finding and explore the relevance of exosome-mediated miRNA delivery in resistance transmission of adr-resistant BCa sublines. We now demonstrated the selective packing of miRNAs within the exosomes (A/exo) derived from adr-resistant BCa cells. The highly expressed miRNAs in A/exo were significantly increased in recipient fluorescent sensitive cells (GFP-S) after A/exo incorporation. Gene ontology analysis of predicted targets showed that the top 30 most abundant miRNAs in A/exo were involved in crucial biological processes. Moreover, A/exo not only loaded miRNAs for its production and release but also carried miRNAs associated with Wnt signaling pathway. Furthermore, A/exo co-culture assays indicated that miRNA-containing A/exo was able to increase the overall resistance of GFP-S to adr exposure and regulate gene levels in GFP-S. Our results reinforce our earlier reports that adr-resistant BCa cells could manipulate a more deleterious microenvironment and transmit resistance capacity through altering gene expressions in sensitive cells by transferring specific miRNAs contained within exosomes. [ABSTRACT FROM AUTHOR]

Breast cancer (BCa) is one of the major deadly cancers in women. However, treatment of BCa is still hindered by the acquired-drug resistance. It is increasingly reported that exosomes take part in the development, metastasis, and drug resistance of BCa. However, the specific role of exosomes in drug resistance of BCa is poorly understood. In this study, we investigate whether exosomes transmit drug resistance through delivering miR-222. We established an adriamycin-resistant variant of Michigan Cancer Foundation-7 (MCF-7) breast cancer cell line (MCF-7/Adr) from a drug-sensitive variant (MCF-7/S). Exosomes were isolated from cell supernatant by ultracentrifugation. Cell viability was assessed by MTT assay and apoptosis assay. Individual miR-222 molecules in BCa cells were detected by fluorescence in situ hybridization (FISH). Then, FISH was combined with locked nucleic acid probes and enzyme-labeled fluorescence (LNA-ELF-FISH). Individual miR-222 could be detected as bright photostable fluorescent spots and then the quantity of miR-222 per cell could be counted. Stained exosomes were taken in by the receipt cells. MCF-7/S acquired drug resistance after co-culture with exosomes from MCF-7/Adr (A/exo) but did not after co-culture with exosomes from MCF-7/S (S/exo). The quantity of miR-222 in A/exo-treated MCF-7/S was significantly greater than in S/exo-treated MCF-7/S. MCF-7/S transfected with miR-222 mimics acquired adriamycin resistance while MCF-7/S transfected with miR-222 inhibitors lost resistance. In conclusion, exosomes are effective in transmitting drug resistance and the delivery of miR-222 via exosomes may be a mechanism. [ABSTRACT FROM AUTHOR]

Aim and Methods Simvastatin ( SV) is reported to improve cognition and slow the progression of Alzheimer's disease ( AD). This study explored the mechanisms underlying the antiamnesic effect of SV in AD using behavior tests, histological examination, western blot analysis, and electrophysiological recording technique in AD model mice created by intracerebroventricular injection (i.c.v.) of Aβ25-35. Results Chronic administration of SV (40 mg/kg/day) for 11 days after Aβ25-35-injection ameliorated the impairment of acquisition performance and probe trail test in Morris water maze task and alternation behavior in Y maze task in Aβ25-35-mice. Aβ25-35-induced apoptosis of hippocampal CA1 pyramidal cells and Aβ25-35-impaired high-frequency stimulation ( HFS)-dependent long-term potentiation ( LTP) induction in hippocampal Schaffer collaterale- CA1 synapse were rescued by SV-treatment. SV prevented Aβ25-35-inhibited protein kinase B (Akt) and extracellular signal-related kinase-2 ( ERK2) phosphorylation, which was sensitive to α7 nicotinic acetylcholine receptor (α7n AChR) antagonist MLA. SV-induced neuroprotection was attenuated by MLA or phosphatidylinositol-3-kinase ( PI3K) antagonist LY294002. SV-rescued LTP induction was blocked by α7n AChR, PI3K or MAPK/ ERK kinase ( MEK) antagonist. Finally, the antiamnesia of SV in Aβ25-35-mice was attenuated by blockage of SV-induced neuroprotection or SV-rescued LTP induction. Conclusion The antiamnesia of SV in Aβ25-35-mice depends on its neuroprotection and synaptic plasticity improvement. [ABSTRACT FROM AUTHOR]

Background: Tumor abnormal protein (TAP) is now gradually applied for early detection of cancers. The aim of this study was to assess the performance of serum TAP in breast cancer patients with a palpable mass., Methods: TAP from peripheral blood of 217 breast cancer patients and 222 with benign tumors patients were compared. The relationships between TAP value and clinical parameters of breast cancer patients were analyzed. Receiver operating characteristic curve was employed to identify the diagnostic value of TAP., Results: Higher TAP level was found in breast cancer patients compared with benign patients ( P <0.001). TAP was not associated with estrogen receptor, progestogen receptor, her-2 expression, tumor size, and pathological degree, but it was significantly associated with the age, lymph node metastasis, and TNM stage ( P =0.023, 0.017, and 0.031, respectively). At a cut-off TAP value of 121 μm2, sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 59.45%, 63.96%, 61.72%, 61.74%, and 61.73%, respectively., Conclusion: Serum TAP may be used as a biomarker in breast cancer diagnosis, but receiver operating characteristic curve indicates it may be limited by its sensitivity/specificity characteristics., (© 2019 by the Association of Clinical Scientists, Inc.)

Aim: To explore the induction effects and mechanism of Solanum lyratum Thumb (ST) on human hepatocellular carcinoma SMMC-7721 cells through the mitochondrial pathway., Methods: The experiments were conducted on three groups: an experimental group (with ST ethanol extracts' concentration being 2.5, 5 and 10 mg/L), a negative control group (with only nutrient solution, 0 mg/L ST ethanol extracts), and a positive control group (2.5 mg/L DDP). The inhibition rate of cell proliferation was checked by using the methyl thiazolyl tetrazolium method, and cell apoptosis was tested by TUNEL method. Furthermore, RT-PCR was used to examine mRNA expression of Fas, FasL, caspase-8, caspase-3, p53 and Bcl-2 genes., Results: Compared with the negative control group, the inhibition and apoptosis rates of the experimental group with different concentrations of ST extracts on human hepatocellular carcinoma SMMC-7721 cells significantly increased ( P < 0.05). Besides, the mRNA expression of FasL and Bcl-2 significantly decreased ( P < 0.05) while the mRNA expression of Fas, caspase-8, caspase-3 and p53 increased significantly. When compared with the positive control group, the experimental groups with 5 mg/L ST ethanol extracts showed effects similar to the positive control group., Conclusion: ST ethanol extracts induced the apoptosis of hepatocellular carcinoma SMMC-7721 cells through up-regulated Fas, caspase-8, caspse-3 and p53, and down-regulated FasL and Bcl-2 in the mitochondrial pathway., Competing Interests: Conflict-of-interest statement: We declare that there are no conflicts of interest to disclose.

While adriamycin (adr) offers improvement in survival for breast cancer (BCa) patients, unfortunately, drug resistance is almost inevitable. Mounting evidence suggests that exosomes act as a vehicle for genetic cargo and constantly shuttle biologically active molecules including microRNAs (miRNAs) between heterogeneous populations of tumor cells, engendering a resistance-promoting niche for cancer progression. Our recent study showed that exosomes from docetaxel-resistance BCa cells could modulate chemosensitivity by delivering miRNAs. Herein, we expand on our previous finding and explore the relevance of exosome-mediated miRNA delivery in resistance transmission of adr-resistant BCa sublines. We now demonstrated the selective packing of miRNAs within the exosomes (A/exo) derived from adr-resistant BCa cells. The highly expressed miRNAs in A/exo were significantly increased in recipient fluorescent sensitive cells (GFP-S) after A/exo incorporation. Gene ontology analysis of predicted targets showed that the top 30 most abundant miRNAs in A/exo were involved in crucial biological processes. Moreover, A/exo not only loaded miRNAs for its production and release but also carried miRNAs associated with Wnt signaling pathway. Furthermore, A/exo co-culture assays indicated that miRNA-containing A/exo was able to increase the overall resistance of GFP-S to adr exposure and regulate gene levels in GFP-S. Our results reinforce our earlier reports that adr-resistant BCa cells could manipulate a more deleterious microenvironment and transmit resistance capacity through altering gene expressions in sensitive cells by transferring specific miRNAs contained within exosomes.

Breast cancer (BCa) is one of the major deadly cancers in women. However, treatment of BCa is still hindered by the acquired-drug resistance. It is increasingly reported that exosomes take part in the development, metastasis, and drug resistance of BCa. However, the specific role of exosomes in drug resistance of BCa is poorly understood. In this study, we investigate whether exosomes transmit drug resistance through delivering miR-222. We established an adriamycin-resistant variant of Michigan Cancer Foundation-7 (MCF-7) breast cancer cell line (MCF-7/Adr) from a drug-sensitive variant (MCF-7/S). Exosomes were isolated from cell supernatant by ultracentrifugation. Cell viability was assessed by MTT assay and apoptosis assay. Individual miR-222 molecules in BCa cells were detected by fluorescence in situ hybridization (FISH). Then, FISH was combined with locked nucleic acid probes and enzyme-labeled fluorescence (LNA-ELF-FISH). Individual miR-222 could be detected as bright photostable fluorescent spots and then the quantity of miR-222 per cell could be counted. Stained exosomes were taken in by the receipt cells. MCF-7/S acquired drug resistance after co-culture with exosomes from MCF-7/Adr (A/exo) but did not after co-culture with exosomes from MCF-7/S (S/exo). The quantity of miR-222 in A/exo-treated MCF-7/S was significantly greater than in S/exo-treated MCF-7/S. MCF-7/S transfected with miR-222 mimics acquired adriamycin resistance while MCF-7/S transfected with miR-222 inhibitors lost resistance. In conclusion, exosomes are effective in transmitting drug resistance and the delivery of miR-222 via exosomes may be a mechanism.

To study the genotypes of hepatitis B virus (HBV) in patients from Chongqing district and determine the prevalence of autoantibodies in these patients. HBV genotyping was carried out by restriction fragment length polymorphism analysis of venous blood serum samples from 252 chronic hepatitis B (CHB) patients and 25 healthy controls. Indirect immunofluorescent assay was used to detect autoantibodies, including antinuclear antibody, anti-mitochondrial antibody, anti-smooth muscle (SM) antibody, and anti-liver and kidney microsomal antibody. Immunospot assay was used to detect anti-ribonucleoprotein/anti-SM antibodies, anti-SS-A antibody, anti-SS-B antibody, anti-scl-70 antibody, and anti-Jo-1 antibody. Correlations between the production of autoantibodies and patient age and sex and various genetypes of HBV were analyzed by the Chi-squared test. The most frequent HBV genotype in CHB patients was B (67.3%), followed by genotype C (32.7%). Genotypes A, D, E, F, G and H were not detected in any of the CHB patients. The positive rate of autoantibodies was higher in the CHB patients than in the healthy group (76.98% vs. 12.00%, X2 = 44.60, P less than 0.05). There was no significant differences in the autoantibodies profiles of CHB patients carrying the B or C genotypes ( X2 = 0.0016, P more than 0.05). The main HBV genotypes in CHB patients in the Chongqing district are B and C. Autoantibodies are prevalent among these CHB patients, and are correlated with patient age and course of liver disease but not HBV genotype or patient sex.

Objective: To study the effect of HCV NS5A protein on HCV IRES-dependent translation in HepG2 cells., Methods: HepG2 cells were co-transfected with a plasmid vector containing a bicistronic transcript carrying Renilla luciferase and firefly luciferase genes separated by HCV IRES sequences, and an expressing vector producing the NS5A protein. The luciferase activity and the mRNA of the luciferase gene were then detected. The NS5A expression was confirmed by fluorescence microscopy., Results: HCV NS5A protein was detected in the cytoplasm of the HepG2 cells transfected with pcDNA-NS5A, and the luciferase activity was up-regulated in the presence of the HCV NS5A protein while the expression of luciferase mRNA showed no difference., Conclusion: HCV NS5A protein can upregulate the HCV IRES activity and this effect is dose-dependent with NS5A.

Objectives: To observe the inhibition of HBV replication and antigen expression by RNA interference aimed at different parts of the HBV genome., Methods: Following the rules of shRNA expression vector design and construction, we constructed seven kinds of sequence specific vectors and two kinds of mutant shRNA expression ones. We then cotransfected those shRNA and HBV expression vectors into HepG2 cells using lipofectamine2000. The level of HBV replication was investigated using Southern blot and the antigen expression using ELISA., Results: The replication of HBV DNA was inhibited by many shRNAs, especially the ones against P1, S2, C2, S1 and X. The inhibition rate against P1 was as high as 95%. Results obtained with ELISA showed that the shRNAs targeting C2, C1 and S2 had high rates of inhibition to HBsAg., Conclusion: The replication and antigen expression of HBV could be inhibited by shRNAs aimed at four different open read frames, and higher inhibition rates of HBV replication and surface antigen expression could be obtained by P1 and C2, respectively.

Objective: To develop a RNAi approach that specifically targets the HCV IRES sequence by vector-expressed short hairpin RNA (shRNA) in vitro, and to assess the inhibitory effect of the shRNA on reporter gene expression., Methods: Eukaryotic expressing plasmids, pIRES-GFP and p5' UTR-Luc containing GFP or luciferase gene controlled by HCV IRES were cotransfected into HepG2 cells with either a RNAi plasmid pshRNA-HCV or a control plasmid pTZU6+1. At 24, 48, 72 hours post transfection, the fluorescence in the transfected cells was studied using fluorescence microscopy. The levels of GFP RNA were determined using RT-PCR and those of protein were determined using Western blot. The activities of luciferase were assayed using a dual luciferase assay system., Results: The introduction of RNAi plasmid efficiently and specifically down-regulated the expression of the reporter gene. RT-PCR showed that the RNAs of GFP gene were distinctly reduced (about 60%) when the pIRES-GFP was cotransfected with pshRNA-HCV, whereas the control vector did not exhibit inhibitory effect on the mRNA level, according to Western blot assay. The luciferase activity also decreased by 60%-70% in comparison to the control plasmid., Conclusion: Our results demonstrate that the shRNA targeting HCV IRES shows a strong inhibitive effect on the expression of the reporter gene controlled by this sequence, suggesting that RNAi-based anti-HCV strategy may represent a potential approach in the therapy of HCV infection.

Aim: To prepare monoclonal antibody (mAb) against Vibrio cholerae O139, which would be used as the gold colloidal reagent strip for rapid detection of O139, and to determine its biological characterization., Methods: BALB/c mice were immunized by inactivated Vibrio cholerae O139. Anti-O139 mAbs were prepared by using hybridoma technique. The specificity of mAb was determined by indirect ELISA and Western blot. The indirect ELISA was used to identify Ig subgroup, detect its titer in ascites and relative affinity, and analyze antigen-binding epitope of mAbs., Results: Two hybridoma cells (O4D7 and O4D10), secreting anti-O139 mAbs were obtained. The Ig subgroups of O4D7 and O4D10 were IgG2b and IgG3, respectively. The mAb's titer in ascites was 1:10(7). The relative affinity of mAb O4D7 was more than 10(5) and that of O4D10 was more than 10(4). The result of additive ELISA showed that two mAbs could recognize different antigen epitopes., Conclusion: The successful preparation of two anti-O139 mAbs provides a powerful tool for the development of a rapid method of detecting Vibrio cholerae O139 infection.

Objective: To study the promoter activity in HepG2 cells of the DNA sequence corresponding to the HCV 5'UTR., Methods: Plasmids, 5'UTR-Luc(+) and 5'UTR-Luc(-) carrying the forward and reverse DNA sequences corresponding to the HCV 5'UTR respectively were constructed, and subsequently transfected into HepaG2 cells. The luciferase activity and the mRNA of the luciferase gene were then detected. The 5'UTR sequence was cloned into a GFP vector to make 5'UTR-EGFP, and then the GFP expression was confirmed by fluorescence microscopy., Results: 5'UTR-Luc(+) had an obvious luciferase activity whereas 5'UTR-Luc(-) had nearly no luciferase activity. The former had a high level of luciferase mRNA while the latter could not be detected. An intense green fluorescence expression was observed in the cells transfected with the plasmid of 5'UTR-EGFP., Conclusion: The forward DNA sequence corresponding to HCV 5'-UTR had an obvious promoter activity in hepG2 cells. It may play an important role in the replication of HCV.

Objective: To synthesize highly pure HBV post-transcriptional regulatory element (HPRE) via transcription in vitro by T7 RNA polymerase., Methods: HPRE gene was amplified by PCR from a template containing HBV complete genomic DNA and cloned into plasmid pGEM-11zf. The cloned DNA sequence was transcribed by T7 RNA polymerase., Results: The construction of HPRE gene recombinant plasmid and production of HPRE via transcription in vitro was successful., Conclusion: In vitro transcription by T7 RNA polymerase can be used to synthesize highly pure HPRE.

Background & Objective: RNA interference (RNAi) has been widely used in tumor gene therapy, antivirus, and gene drug selection. Survivin gene is highly expressed in ovarian cancer cell line SKOV3 and drug-resistant cell line SKOV3/ADM, and is an ideal target of gene therapy for ovarian cancer. This study was to explore effect of RNAi-mediated Survivin gene silencing on apoptosis of SKOV3 and SKOV3/ADM cells., Methods: Recombinant plasmid pshRNA-Survivin was transfected into SKOV3 and SKOV3/ADM cells. The expression of Survivin was detected by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. The apoptosis of SKOV3 and SKOV3/ADM cells after transfection were evaluated by AO/EB dyeing, TUNEL, and flow cytometry., Results: After transfection of pshRNA-Survivin, mRNA and protein levels of Survivin gene in SKOV3 and SKOV3/ADM cells were obviously reduced; the apoptosis of SKOV3 and SKOV3/ADM cells were significantly higher in transfection group than in control group (P0.01); 48 h after transfection, the apoptosis rate was 14.05% in SKOV3 cells, and 21.02% in SKOV3/ADM cells, no obvious apoptosis was detected in control cells., Conclusion: pshRNA-Survivin could reduce the expression of Survivin gene, and induce apoptosis of SKOV3 and SKOV3/ADM cells.

Objective: To investigate the differences among various transmission generation of severe acute respiratory syndrome (SARS) by comparing the corresponding clinical data., Methods: The clinical data of 84 patients with SARS were retrospectively studied, 66 women and 18 men, mean age (29.2 +/- 10.3) years old, 96.4% of whom were health care workers. All subjects had exposure to a source patient and the epidemic progressively propagated in a short time. For the infectious chain, we defined these patients who had exposure to a source patient as the primary cases, which included 35 patients (41.7%). Patients who got the disease by exposure to the primary cases were defined as secondary cases, which included 34 patients (40.5%). Similarly, the tertiary cases included 15 patients (17.9%)., Results: (1) No statistical differences in age, sex ratio, incubation period and hospitalization duration among various infectious generations were found (P > 0.05). (2) With descending in infectious generations, the initial temperature lowered, and cases with cough decreased (P < 0.05) with no statistical differences in the peak temperature, other accompanying symptoms and leukopenia (P > 0.05). (3) With descending in infectious generations, the course from the appearance of pulmonary lesions to their resolution shortened (P < 0.05). No differences were found in the maximal involved pulmonary fields, duration from initial fever to appearance of pulmonary lesions and course from the initial pulmonary lesions to their peak among the above three generations (P > 0.05). (4) No statistical differences were found in ways of oxygen therapy and classes of antibiotics prescribed (P > 0.05). With descending in infectious generation, cases treated with methylprednisolone, human gamma-immunoglobulin, interferon-alpha, and antiviral drugs (oral ribavirin or oseltamivir) increased (P < 0.05) and the duration of their use also increased (P < 0.05)., Conclusions: With descending in infectious generations, the clinical features of SARS may become ameliorated.

Background: Severe acute respiratory syndrome (SARS) is characterized by both an atypical pneumonia and efficient nosocomial transmission. However, it remains unknown whether the infectivity and the virulence of the pathogen will change throughout the successive transmission. This study was conducted to compare the clinical features and management regimens of patients with SARS among the multiple generations from nosocomial transmission initiated by a super-spreader., Methods: The clinical data of 84 epidemiologically-linked SARS patients from a hospital outbreak were retrospectively studied. All patients, in whom a clear-cut transmission generation could be noted, had a direct or indirect exposure to the index patient and the epidemic successively propagated through the multiple generations of cases within a short period of time., Results: There were 66 women and 18 men with mean age of (29.2 +/- 10.3) years in this cluster; and 96.4% of whom were health care workers. Detailed contact tracing identified 35 (41.7%) first-generation cases, 34 (40.5%) second-generation cases, and 15 (17.8%) third-generation cases. No statistical differences among the multiple generations of transmission were found in terms of age, gender, incubation period and length of hospital stay. With the advanced transmission generations, the initial temperature lowered, the number of cases with dry cough decreased. There were no statistical differences in the peak temperature and duration of fever, other accompanying symptoms, leucopenia; however, the time from initial pulmonary infiltrates to radiographic recovery shortened (P < 0.05). No differences were found in maximum number of lung fields involved, duration from the onset of fever to the occurrence of pulmonary infiltrates and time from the initial pulmonary infiltrate to its peak among the multiple transmission generations (P > 0.05). No statistical differences were found in modes of oxygen therapy and sorts of antibiotics prescribed among the various transmission generations (P > 0.05); however, as with the advanced transmission generations, the number of cases prescribed with methylprednisolone, human gamma-globulin, interferon-alpha, antiviral drugs (oral ribavirin or oseltamivir) increased (P < 0.05) and time from admission to starting these medication shortened (P < 0.05)., Conclusions: There is no evidence that SARS infection will evolve or transmit within a fashion that permits it to become less powerful throughout the successive transmission within a short time.

Objective: To investigate measures to prevent the outbreak of severe acute respiratory syndrome (SARS) in healthcare workers in isolation units., Methods: The architectural factors and the infection of healthcare workers in different wards in our hospital between 30 January 2003 and 30 March 2003 were analyzed., Results: Four kinds of isolation wards were evaluated, including the ward where the thirty-first bed lied in on the twelfth floor, the laminar flow ward in the intensive care unit (ICU) where the tenth bed lied in on the fifteenth floor, the ward where the twenty-seventh bed lied in on the thirteenth floor of Building A, and thirty wards on the fourteenth to eighteenth floors of Building B. The ratios (m2/m3) of the area of the ventilation windows to the volume of the room were 0, 0, 1:95 and 1:40, respectively. Numbers of SARS cases in the wards mentioned above were 1, 1, 1 and 96, respectively. The total lengths (hour) of hospitalization were 43, 168, 110 and 1,272, respectively. The infection rates of the healthcare workers in the areas mentioned above were 73%, 32%, 28% and 2%, respectively. The difference of the infection rates was of statistical significance., Conclusion: In addition to strict personal protective measures, isolation of SARS cases in wards with high ratio of the area of ventilation windows to the volume of the room and good ventilation may be the key to preventing the outbreak of SARS in healthcare workers in isolation units.

Objective: To describe a hospital outbreak of severe acute respiratory syndrome (SARS) and summarize the clinical features and therapeutic approaches., Methods: Clinical data in this cohort were collected prospectively as they were identified., Results: The outbreak started with a SARS patient from the community on 30 January 2003, followed by a total of 96 people [76 women and 20 men; mean age (29.5 +/- 10.3) years; 93.8% of whom were health care workers] infected in a short period of time after their exposure to this source patient. The incubation period ranged from 1 to 20 days, with a mean of (5.9 +/- 3.5) days. The initial temperature was (38.3 +/- 0.6) degrees C, while the highest was (39.2 +/- 0.6) degrees C (P < 0.001), with a mean fever duration of (9.0 +/- 4.2) days. Other common symptoms included fatigue, cough, mild sputum production, chills, headache, general malaise and myalgia. The radiographic changes were predominantly bilateral and in the middle or lower lung zones. Leukopenia was observed in 67.7% of this cohort. The mean lowest oxygen saturation was (94.8 +/- 3.1)% with supplementary oxygen through a nasal cannula. 68.8% of the patients were treated with methylprednisolone for a mean period l of (4.9 +/- 2.4) days. The initial dose was (67.3 +/- 28.2) mg/d and the maximal dose was (82.4 +/- 30.5) mg/d. Ninety-five patients (99.0%) had a complete clinical recovery, and 1 patient died of progressive acute respiratory distress syndrome. The mean hospitalized duration was (17.2 +/- 8.0) days., Conclusion: SARS appears to be highly contagious and potentially lethal among health care workers, characterized by acute onset and rapid progression. Corticosteroids, antibiotics, human gamma-globulin, interferon-alpha, and antiviral drugs, although used empirically, might be of some benefits in shortening the clinical course.