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61.
The intrathecal immune response in 114 patients with clinically diagnosed acute poliomyelitis was studied by measuring poliovirus-specific immunoglobulin M (IgM) antibodies in cerebrospinal fluid (CSF) by a mu-capture immunoassay and by assessing the ratio between levels of poliovirus-neutralizing antibodies in serum and CSF. Fecal specimens were used for attempts to isolate the causative agents. Eighty-five percent of CSF specimens collected during the first 15 days of disease contained virus-specific IgM antibodies. Forty-five of 48 tested children (94%) also showed virus-specific IgM responses in their sera. Later on, the antibody levels decreased, and positive results after 30 days of onset of paralytic symptoms were rare. If the presence of poliovirus-specific IgM antibodies in the CSF was considered diagnostic, more cases were confirmed by this test than by virus isolation. A relative increase in poliovirus-neutralizing antibodies in the CSF was observed in about one-third of the cases; in all but three cases the increase was observed together with the presence of virus-specific IgM antibodies. A systemic virus-specific response can be seen and poliovirus can be isolated from a subclinically infected individual suffering from a concomitant poliomyelitis-like disease, while positive results by the two methods demonstrating an intrathecal immune response are likely to indicate a true causal relationship between infection and disease. Demonstration of poliovirus-specific IgM antibodies in the CSF thus appears to be a sensitive and specific method for laboratory confirmation of clinically diagnosed poliomyelitis.  相似文献   
62.
Isao Oze  Hidemi Ito  Yuriko N. Koyanagi  Sarah Krull Abe  Md. Shafiur Rahman  Md. Rashedul Islam  Eiko Saito  Prakash C. Gupta  Norie Sawada  Akiko Tamakoshi  Xiao-Ou Shu  Ritsu Sakata  Reza Malekzadeh  Ichiro Tsuji  Jeongseon Kim  Chisato Nagata  San-Lin You  Sue K. Park  Jian-Min Yuan  Myung-Hee Shin  Sun-Seog Kweon  Mangesh S. Pednekar  Shoichiro Tsugane  Takashi Kimura  Yu-Tang Gao  Hui Cai  Akram Pourshams  Yukai Lu  Seiki Kanemura  Keiko Wada  Yumi Sugawara  Chien-Jen Chen  Yu Chen  Aesun Shin  Renwei Wang  Yoon-Ok Ahn  Min-Ho Shin  Habibul Ahsan  Paolo Boffetta  Kee Seng Chia  You-Lin Qiao  Nathaniel Rothman  Wei Zheng  Manami Inoue  Daehee Kang  Keitaro Matsuo 《International journal of cancer. Journal international du cancer》2024,154(7):1174-1190
Body fatness is considered a probable risk factor for biliary tract cancer (BTC), whereas cholelithiasis is an established factor. Nevertheless, although obesity is an established risk factor for cholelithiasis, previous studies of the association of body mass index (BMI) and BTC did not take the effect of cholelithiasis fully into account. To better understand the effect of BMI on BTC, we conducted a pooled analysis using population-based cohort studies in Asians. In total, 905 530 subjects from 21 cohort studies participating in the Asia Cohort Consortium were included. BMI was categorized into four groups: underweight (<18.5 kg/m2); normal (18.5-22.9 kg/m2); overweight (23-24.9 kg/m2); and obese (25+ kg/m2). The association between BMI and BTC incidence and mortality was assessed using hazard ratios (HR) and 95% confidence intervals (CIs) by Cox regression models with shared frailty. Mediation analysis was used to decompose the association into a direct and an indirect (mediated) effect. Compared to normal BMI, high BMI was associated with BTC mortality (HR 1.19 [CI 1.02-1.38] for males, HR 1.30 [1.14-1.49] for females). Cholelithiasis had significant interaction with BMI on BTC risk. BMI was associated with BTC risk directly and through cholelithiasis in females, whereas the association was unclear in males. When cholelithiasis was present, BMI was not associated with BTC death in either males or females. BMI was associated with BTC death among females without cholelithiasis. This study suggests BMI is associated with BTC mortality in Asians. Cholelithiasis appears to contribute to the association; and moreover, obesity appears to increase BTC risk without cholelithiasis.  相似文献   
63.
The “delayed infection hypothesis” states that a paucity of infections in early childhood may lead to higher risks of childhood leukemia (CL), especially acute lymphoblastic leukemia (ALL). Using prospectively collected data from six population-based birth cohorts we studied the association between birth order (a proxy for pathogen exposure) and CL. We explored whether other birth or parental characteristics modify this association. With 2.2 × 106 person-years of follow-up, 185 CL and 136 ALL cases were ascertained. In Cox proportional hazards models, increasing birth order (continuous) was inversely associated with CL and ALL; hazard ratios (HR) = 0.88, 95% confidence interval (CI): (0.77–0.99) and 0.85: (0.73–0.99), respectively. Being later-born was associated with similarly reduced hazards of CL and ALL compared to being first-born; HRs = 0.78: 95% CI: 0.58–1.05 and 0.73: 0.52–1.03, respectively. Successive birth orders were associated with decreased CL and ALL risks (P for trend 0.047 and 0.055, respectively). Multivariable adjustment somewhat attenuated the associations. We found statistically significant and borderline interactions between birth weight (p = 0.024) and paternal age (p = 0.067), respectively, in associations between being later-born and CL, with the lowest risk observed for children born at <3 kg with fathers aged 35+ (HR = 0.18, 95% CI: 0.06–0.50). Our study strengthens the theory that increasing birth order confers protection against CL and ALL risks, but suggests that this association may be modified among subsets of children with different characteristics, notably advanced paternal age and lower birth weight. It is unclear whether these findings can be explained solely by infectious exposures.  相似文献   
64.
Ebselen prevents noise-induced excitotoxicity and temporary threshold shift   总被引:1,自引:0,他引:1  
This investigation tested the hypothesis that a noise-induced temporary threshold shift (TTS) can be attenuated by a peroxynitrite scavenger, ebselen (2-phenyl-1,2-benzisoselenazol-3(2H)-one). Guinea pigs received an oral dose of the vehicle or 10 mg/kg ebselen 1 h before exposure to 115 dB SPL 4-kHz octave band noise for 3 h. In controls, auditory brainstem response (ABR) thresholds increased by 25–45 dB immediately after noise and returned to pre-exposure baseline thresholds 7 days later. Ebselen eliminated this ABR threshold shift following noise exposure. In controls, swelling of the afferent dendrites beneath the inner hair cells was evident immediately after noise, whereas ebselen significantly reduced this pathology. These findings suggest that scavenging peroxynitrite can attenuate noise-induced excitotoxicity and, thereby, TTS.  相似文献   
65.
66.
Ebselen attenuates cochlear damage caused by acoustic trauma   总被引:3,自引:0,他引:3  
Ebselen (2-phenyl-1,2-benzisoselenazol-3(2H)-one), a seleno-organic compound, mimics glutathione peroxidase and reacts with peroxynitrite. It is reported to protect against gentamicin- and cisplatin-induced ototoxicity. We investigated whether it protects the cochlea from acoustic trauma. Male pigmented guinea pigs (250-300 g) with normal auditory brainstem response (ABR) thresholds were exposed for 5 h to 125 dB sound pressure level octave band noise centered at 4 kHz. One hour before and 18 h after exposure, they received orally 0.25 ml chloroform solution containing 0, 10, or 30 mg/kg ebselen (n=6, 5 and 5, respectively). The protective effect of ebselen was evaluated by ABR measurement and quantitative hair cell assessment. Treatment significantly (P<0.01) reduced the extent of permanent threshold shifts and outer hair cell loss. Interestingly, the protective effect of a 30 mg/kg dose was less than that of a 10 mg/kg dose. There were no adverse systemic or auditory function effects in three unexposed control subjects given 30 mg/kg ebselen. These findings indicate that ebselen attenuates noise-induced cochlear damage. The concentration that provides optimal protection against such damage has now to be determined.  相似文献   
67.

Objective

To isolate the entomopathogenic fungus Metarhizium anisopliae (M. anisopliae) in the local environment, and evaluate its efficacy against the suspected dengue vector Aedes albopictus in Pakistan.

Methods

According to the standard procedure, M. anisopliae was isolated from the dead mosquitoes which were collected from the field or dead after the collection. Bioassay was performed to determine its efficacy.

Results

The results indicated that M. anisopliae had larvicidal effect with LC50 value 1.09×105 and LC90 value 1.90×1013 while it took 45.41 h to kill 50% of tested population.

Conclusions

Taking long time to kill 50% population when compare with the synthetic insecticides, is the only drawback for the use of entomopathogenic fungus but these bio-pesticides are safe for the use.  相似文献   
68.
AIMS: To compare insulin lispro with soluble human insulin in patients with Type 2 diabetes mellitus fasting during Ramadan, with respect to the rate of hypoglycaemic episodes and postprandial blood glucose values after the main meal after sunset. METHODS: The insulins were compared in an open-label, randomized, cross-over study of 70 outpatients. Hypoglycaemic episodes were recorded by the patients in a self-monitoring diary. Fasting, 1-h and 2-h postprandial blood glucose values were recorded by the patient on three consecutive days at the end of each treatment period. RESULTS: The fasting blood glucose values before sunrise (P>0.4) and after sunset (P>0.6) were similar and did not differ significantly between both treatment groups. The rise in blood glucose after the main meal after sunset was 3.0+/-0.4 mmol/l after 1 h in the insulin lispro treatment group compared to 4.3+/-0.4 mmol/l in the soluble insulin treatment group (P<0.01), and 2.6+/-0.4 mmol/l after 2h with insulin lispro compared to 4.0+/-0.5 mmol/l with soluble insulin (P<0.008). Mean hypoglycaemic episodes per patient over 14 days were 1.3+/-0.1 vs. 2.6+/-0.2, P<0.002, respectively, for insulin lispro and soluble insulin. Most hypoglycaemic episodes occurred during the time period from 6 h after the before sunrise meal until breaking the fast after sunset. CONCLUSIONS: The significantly lower rate of hypoglycaemic episodes combined with better control of postprandial blood glucose suggest insulin lispro may be more suitable prandial insulin for patients treated with Type 2 diabetes who fast during Ramadan.  相似文献   
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