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1.
Neurosurgical procedures can result in brain injury by various means including direct trauma, hemorrhage, retractor stretch, and electrocautery. This surgically-induced brain injury (SBI) can cause post-operative complications such as brain edema. By creating a mouse model of SBI, we tested whether NADPH oxidase, an important reactive oxygen species producing enzyme, is involved in SBI using transgenic mice lacking gp91phox subunit of NADPH oxidase (gp91phox KO) and apocynin, a specific inhibitor of NADPH oxidase. Neurological function and brain edema were evaluated at 24 h post-SBI in gp91phox KO and wild-type littermates grouped into SBI and sham-surgery groups. Alternatively, mice were grouped into vehicle- and apocynin-treated (5 mg/kg, i.p. 30 min before SBI) groups. Oxidative stress indicated by lipid peroxidation (LPO) was measured at 3 and 24 h post-SBI. The gp91phox KO mice, but not the apocynin-treated mice showed significantly improved neurological scores. Brain edema was observed in both gp91phox KO and wild-type groups after SBI; however, there was no significant difference between these two groups. Brain edema was also not affected by apocynin-pretreatment. LPO levels were significantly higher in SBI group in both gp91phox KO and wild-type groups as compared to sham group. A trend, although without statistical significance, was noted towards attenuation of LPO in the gp91phox KO animals as compared to wild-type group. LPO levels were significantly attenuated at 3 h post-SBI by apocynin-pretreatment but not at 24 h post-SBI. These results suggest that chronic and acute inhibition of NADPH oxidase activity does not reduce brain edema after SBI. Long-term inhibition of NADPH oxidase, however improves neurological functions after SBI.  相似文献   
2.
Autopsy study of maternal deaths.   总被引:2,自引:0,他引:2  
OBJECTIVES: To obtain an insight into the underlying disorder or pathologies in different organs or systems, and to attempt clinicopathologic correlation in maternal deaths. METHODS: This is a retrospective study of 95 maternal autopsies done from 1993 to 2000 in Sassoon General Hospital, Pune, India. External examination, in situ examination, gross and microscopic examination was done in each case. The cause of death was arrived at after reviewing clinical details, available investigations, morphological findings, and clinicopathologic correlation. RESULTS: Ninety-five (45.02%) out of 211 maternal deaths were autopsied. Out of 95, there were 47 (49.5%) direct obstetric deaths, and 33 (34.7%) indirect obstetric deaths. Fifteen (15.8%) deaths were unrelated to pregnancy, 14 of which were due to infections. CONCLUSIONS: Hypertensive disorders associated with pregnancy (24.2%) and anemia (14.7%) were most common. In the hypertensive group, important findings were disseminated intravascular coagulation, hemorrhages in different organs and thromboemboli. Two cases were HIV seropositive. The autopsy helped to elucidate factors contributing to death and pathology in different organ systems.  相似文献   
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Bacterial biofilms are a cause of contamination in a wide range of medical and biological areas. Ultrasound is a mechanical energy that can remove these biofilms using cavitation and acoustic streaming, which generate shear forces to disrupt biofilm from a surface. The aim of this narrative review is to investigate the literature on the mechanical removal of biofilm using acoustic cavitation to identify the different operating parameters affecting its removal using this method. The properties of the liquid and the properties of the ultrasound have a large impact on the type of cavitation generated. These include gas content, temperature, surface tension, frequency of ultrasound and acoustic pressure. For many of these parameters, more research is required to understand their mechanisms in the area of ultrasonic biofilm removal, and further research will help to optimise this method for effective removal of biofilms from different surfaces.  相似文献   
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Thermoresponsive poly(N-isopropylacrylamide)-grafted silica nanoparticles (SiNPs) have been synthesized and fully characterized by ATR-FTIR, TGA, HRTEM, BET and DLS analysis. Hybrid solid phase extraction (SPE) beds with tuneable pore size and switchable surface chemistry were prepared by packing the polymer-grafted nanoparticles inside SPE cartridges. The cartridges were tested by checking the thermo-regulated elution of model compounds, namely methylene blue, caffeine and amoxicillin. Extraction of the analytes and regeneration of the interaction sites on the sorbent surface was carried out entirely in water solution by changing the external temperature below and above the lower critical solution temperature (LCST) of the polymer. The results demonstrate that the elution of model compounds depends on the temperature-regulated size of the inter-particle voids and on the change of surface properties of the PNIPAM-grafted nanoparticles from hydrophilic to hydrophobic.

Thermoresponsive poly(N-isopropylacrylamide)-grafted silica nanoparticles were synthesized and used to prepare solid phase extraction sorbents with switchable pore size and surface chemistry for temperature-regulated extraction of water pollutants.  相似文献   
9.

Objective

Evidence has linked economic hardship with increased intimate partner violence (IPV) perpetration among males. However, less is known about how economic debt or gender norms related to men''s roles in relationships or the household, which often underlie IPV perpetration, intersect in or may explain these associations. We assessed the intersection of economic debt, attitudes toward gender norms, and IPV perpetration among married men in India.

Methods

Data were from the evaluation of a family planning intervention among young married couples (n=1,081) in rural Maharashtra, India. Crude and adjusted logistic regression models for dichotomous outcome variables and linear regression models for continuous outcomes were used to examine debt in relation to husbands'' attitudes toward gender-based norms (i.e., beliefs supporting IPV and beliefs regarding male dominance in relationships and the household), as well as sexual and physical IPV perpetration.

Results

Twenty percent of husbands reported debt. In adjusted linear regression models, debt was associated with husbands'' attitudes supportive of IPV (b=0.015, p=0.004) and norms supporting male dominance in relationships and the household (b=0.006, p=0.003). In logistic regression models adjusted for relevant demographics, debt was associated with perpetration of physical IPV (adjusted odds ratio [AOR] = 1.4, 95% confidence interval [CI] 1.1, 1.9) and sexual IPV (AOR=1.6, 95% CI 1.1, 2.1) from husbands. These findings related to debt and relation to IPV were slightly attenuated when further adjusted for men''s attitudes toward gender norms.

Conclusion

Findings suggest the need for combined gender equity and economic promotion interventions to address high levels of debt and related IPV reported among married couples in rural India.Intimate partner violence (IPV) perpetrated by male partners or husbands occurs in high proportions globally as well as in low- to middle-income countries such as India.1,2 One recent multi-country household study found that 37% of men in India reported having ever perpetrated physical violence against a female intimate partner in their lifetime. The health burden of IPV has been well demonstrated, with significant effects on women''s sexual and reproductive health (e.g., increased sexually transmitted infections, unintended pregnancy, and poor pregnancy outcomes),35 mental health (e.g., anxiety, depression, and substance use),6,7 as well as a multitude of other poor health outcomes among women and their children (e.g., maternal and child malnutrition and infant death).8,9Recent research among women has identified economic hardship (e.g., financial dependence on male partners and economic instability) as increasing women''s vulnerability to IPV.10,11 Although studies have found an association between economic stressors and reports of male IPV perpetration,1216 no research has examined debt in relation to these outcomes.Debt and other economic decisions in the context of marriage, particularly in rural India, are largely under the control of husbands. Taking on debt may be associated with economic hardship, heightening stress levels among men, and, in turn, IPV. Also, previous work documenting the association between economic hardship and increased IPV perpetration by males1215 has largely been explained by perceptions related to men''s roles financially within the family (e.g., men who do not feel that they are providing financially for their families may perceive that they are not fulfilling their roles as husbands/males, and this perception related to lack of role fulfillment may escalate into violence). Given that a decision to take on debt appears to be largely controlled by men in this context and likely tied to their perceived role of providing financially for the family, a man''s decision to take out loans may be determined, in part, by their support of masculine gender norms (e.g., a man''s role in the family and male dominance and control in the household). In addition, given previous work highlighting the association between masculine gender norms and a number of risk behaviors among boys and men (e.g., substance and tobacco use and behaviors resulting in unintentional injury),1721 such gender norms may also be linked to taking on risks associated with debt, as well as debt-acquiring behaviors (e.g., spending money on nonessential goods such as alcohol).Gender norms pertaining to IPV, relationships, and the household are also important driving factors in terms of understanding men''s behaviors related to IPV. Cross-cultural research has shown that societies with greater gender inequities in social norms and policies have a higher prevalence of IPV.21 In the context of India and elsewhere, women''s low status in families and high levels of societal tolerance and acceptance of IPV promote IPV.22More research is needed to understand economic hardship, and debt specifically, in relation to attitudes toward gender norms and IPV perpetration. Many studies have hypothesized that stress related to economic hardship and debts increases IPV perpetration;1215 however, less research has sought to understand the role of attitudes supportive of men''s more traditional gender norms in relationships or households in contributing to decisions to take on debt as well as in terms of explaining its association with increased IPV perpetration. Increased understanding of the mechanisms that explain associations between economic hardship/debt and IPV is needed to inform prevention approaches, particularly given the increasing number of economic promotion interventions being implemented globally and throughout India.Thus, the primary objective of the current study was to assess household debt in relation to husbands'' support of gender-inequitable norms and norms promoting IPV as well as husbands'' use of IPV against wives. The secondary objective of this study was to assess whether or not gender-based attitudes are important factors in debt and IPV, as well as in explaining an association between debt and increased risk for IPV perpetration among husbands.  相似文献   
10.
Rare earth (RE) ions are known to improve the magnetic interactions in spinel ferrites if they are accommodated in the lattice, whereas the formation of a secondary phase leads to the degradation of the magnetic properties of materials. Therefore, it is necessary to solubilize the RE ions in a spinel lattice to get the most benefit. In this context, this work describes the synthesis of Co–Zn ferrite nanoparticles and the Gd3+ doping effect on the tuning of their magnetic properties. The modified sol–gel synthesis approach offered a facile way to synthesize ferrite nanoparticles using water as the solvent. X-ray diffraction with Rietveld refinement confirmed that both pure Co–Zn ferrite and Gd3+ substituted Co–Zn ferrite maintained single-phase cubic spinel structures. Energy dispersive spectroscopy was used to determine the elemental compositions of the nanoparticles. Field and temperature dependent magnetic characteristics were measured by employing a vibration sample magnetometer in field cooled (FC)/zero field cooled (ZFC) modes. Magnetic interactions were also determined by Mössbauer spectroscopy. The saturation magnetization and coercivity of Co–Zn ferrite were improved with the Gd3+ substitution due to the Gd3+ (4f7)–Fe3+ (3d5) interactions. The increase in magnetization and coercivity makes these Gd3+ substituted materials applicable for use in magnetic recording media and permanent magnets.

Rare earth (RE) ions are known to improve the magnetic interactions in spinel ferrites if they are accommodated in the lattice, whereas the formation of a secondary phase leads to the degradation of the magnetic properties of materials.  相似文献   
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