微乳液反应法制备磺胺嘧啶银均匀微晶及其质量评价

目的：应用微乳液反应法制备磺胺嘧啶银均匀微晶,并评价其质量。方法：利用磺胺嘧啶钠微乳和硝酸银微乳混合后反应的方法,制备磺胺嘧啶银均匀微晶,用透射电镜观察其形态和大小,以Ｘ－射线衍射分析、红外光谱、核磁共振、差热分析等手段检测磺胺嘧啶银均匀微晶各种理化特性。结果：磺胺嘧啶银均匀微晶的粒径大小约为２～４μｍ,均匀微晶的结晶性好,纯度高。体外抑菌实验表明该品比市售磺胺嘧啶银具有更好的抑菌效果。结论：用微乳液反应法能获得磺胺嘧啶银均匀微晶。     

Economic costs of functional dyspepsia

Dyspepsia is defined as chronic or recurrent symptoms believed to originate in the upper gastrointestinal tract. When routine investigation results in no identifiable explanation for those symptoms patients are labelled as having functional dyspepsia. In community-based surveys, approximately 30% of the otherwise apparently healthy population report dyspeptic symptoms and the majority are believed to have functional dyspepsia. Although only 1 in 4 or 5 patients make use of healthcare resources, this patient category is one of the largest in ambulatory care (1.6 to 5% of all consultations in general practice). The annual frequency of consultations for functional dyspepsia in Sweden has been estimated at 47 per 1000 population. In consequence of its high prevalence and associated absenteeism, the total costs of functional dyspepsia are considerable. In Sweden in 1981, the costs were estimated at $US55 000 per 1000 population ($US113 630 in 1991 dollars). The most cost-effective management strategy remains to be defined. Evidence is accumulating that the traditional 'wait-and-see' policy with initial empirical therapeutic trials without investigation may not be the most cost conserving strategy.     

Dynamic regulation of middle cerebral artery blood flow velocity in aging and hypertension

BACKGROUND AND PURPOSE: Although aging and hypertension may predispose hypertensive elderly subjects to cerebral hypoperfusion during orthostatic stress, their effects on the acute cerebral autoregulatory response to hypotension are not known. METHODS: Continuous middle cerebral artery blood flow velocity (BFV) (transcranial Doppler ultrasound) and mean arterial pressure (MAP, Finapres) were measured in response to (1) acute hypotension during standing, (2) steady-state sitting and standing, and (3) hypercarbia during CO(2) rebreathing in 10 healthy young subjects (age 24+/-1 years), 10 healthy elderly subjects (age 72+/-3 years), and 10 previously treated hypertensive elderly (age 72+/-2 years) subjects. CO(2) reactivity was computed as the slope of cerebrovascular conductance (CVC=BFV/MAP) versus end-expiratory CO(2). Coherence, transfer magnitudes, and phases between low-frequency MAP and BFV signals were computed from their autospectra during 5 minutes of sitting and standing. RESULTS: MAP fell to a similar extent in all groups by an average of 21 to 26 mm Hg (22% to 26%) within 30 seconds of standing. Mean BFV also fell in all subjects but significantly less in the older subjects (-4.7+/-0. 7 cm/s in hypertensives and -5.3+/-1.2 cm/s in normotensives, P=NS) compared with younger subjects (-10.1+/-1.1 cm/s, P<0.05). CO(2) reactivity was greater in the young subjects (0.19+/-0.01) compared with normotensive (0.14+/-0.01, P<0.05) and hypertensive elderly subjects (0.11+/-0.02, P<0.05) (P=NS between elderly groups). Fewer hypertensive subjects had coherence between MAP and BFV signals; for subjects with coherence, there were no significant group differences in phase or transfer magnitudes in either sitting or standing positions. CONCLUSIONS: Despite reduced CO(2) reactivity, elderly normotensive and previously treated hypertensive subjects retain cerebral autoregulatory capacity in response to acute orthostatic hypotension.     

Involvement of the proliferating cell nuclear antigen (PCNA) in DNA repair induced by alkylating agents and oxidative damage in human fibroblasts

The involvement of the proliferating cell nuclear antigen (PCNA) in the process of DNA repair induced by alkylating agents or by oxidative damage was investigated in human quiescent fibroblasts by immunofluorescence and flow cytometry. Transition from soluble to the DNA-bound form of PCNA, was taken as the parameter to determine its involvement in repair DNA synthesis. Treatment with the alkylating agents methylmethane sulfonate and N-methyl-N'-nitro-N-nitrosoguanidine resulted in the rapid and dose-dependent increase in the nuclear binding of PCNA. Similar results were obtained with compounds such as hydrogen peroxide or tert-butyl hydroperoxide, which are known to induce oxidative DNA damage. Tert-butyl hydroperoxide may also generate malondialdehyde through a reaction of lipid peroxidation. This mutagenic and carcinogenic product has been previously shown to form adducts with DNA. Therefore, the possibility that tert-butyl hydroperoxide could induce DNA damage through this pathway was investigated by incubating cells directly in the presence of malondialdehyde. Such treatment resulted in an increase in immunofluorescence associated with nuclear-bound PCNA. The ability of oxidative and alkylating agents to induce the nuclear binding of PCNA was also assessed in proliferating cells. In these conditions, treatment with hydrogen peroxide or methylmethane sulfonate, resulted in an increase in nuclear-bound PCNA in the G1 and in the G2 + M compartments, but not in S phase. At longer times after treatment, PCNA immunostaining was reduced to basal levels, while an increase in nuclear binding of p21(waf1/cip1) protein was found in concomitance with cell-cycle arrest. These results indicate that agents inducing DNA base alterations in vivo, promote the nuclear binding of PCNA. These lines of evidence support the role of a PCNA-dependent reaction in the base excision repair system.      

Effect of the viable-yellow (A(vy)) agouti allele on skin tumorigenesis and humoral hypercalcemia in v-Ha-ras transgenic TGxAC mice

We previously reported that papillomas can arise from the follicular epithelium of v-Ha-ras transgenic TGxAC mice. Since the viable-yellow mutation (A(vy)) of the mouse agouti gene which regulates coat color pigmentation by acting within the micro-environment of the hair follicle has been shown to function as a tumor promoter in the liver, we hypothesized that it may also play a role in TGxAC skin tumorigenesis. Endogenous agouti protein product was detected in the outer root sheath of anagen hair follicles following plucking of the hair shaft, but not in the interfollicular epithelium, in TGxAC mice on an FVB/N genetic background. It was also detected in papillomas from these mice produced by 12-O-tetradecanoylphorbol-13-acetate (TPA) treatment or plucking. Expression of the A(vy) allele in the v-Ha-ras transgenic TGxAC mouse line results in an approximately 2-fold increase in papilloma development compared with controls which did not carry the A(vy) allele following twice-weekly treatment with 1.25, 2.5 or 5.0 microg TPA. In addition, TPA-treated, papilloma-bearing F1 mice which carried the A(vy) allele, but not F1 mice which did not carry the A(vy) allele, exhibited a syndrome of humoral hypercalcemia mediated by parathyroid hormone-related protein (PTHrP) that led to weight loss, hypercalcemia and hypophosphatemia. Thus, we conclude that the A(vy) allele can influence the development of skin tumors and PTHrP-mediated humoral hypercalcemia in v-Ha-ras transgenic TGxAC mice.      

Non-invasive detection of fecal protein kinase C betaII and zeta messenger RNA: putative biomarkers for colon cancer

We have developed a non-invasive method utilizing feces, containing sloughed colonocytes, as a sensitive technique for detecting diagnostic colonic biomarkers. In this study, we used the rat colon carcinogenesis model to determine if changes in fecal protein kinase C (PKC) expression have predictive value in monitoring the neoplastic process. Weanling rats were injected with saline or azoxymethane (AOM) and 36 weeks later fecal samples and mucosa were collected, poly A+ RNA isolated, and quantitative RT-PCR performed using primers to PKC betaII and zeta. Fecal PKC betaII and zeta mRNA levels were altered by the presence of a tumor, with tumor-bearing animals having a 3-fold higher (P < 0.05) PKC betaII expression as compared with animals without tumors. In addition, AOM-injection increased mucosal PKC betaII mRNA expression compared with saline controls. No effect of tumor incidence on mucosal PKC betaII expression was observed. In contrast, fecal PKC zeta expression was 2.5-fold lower (P < 0.05) in animals injected with azoxymethane versus saline. Since tumor incidence exerts a reciprocal effect on fecal PKC betaII and zeta mRNA expression, data were also expressed as the ratio between PKC betaII and zeta. The isozyme ratio was strongly related to tumor incidence, i.e. ratio for animals with tumors was 2.18 +/- 1.25, animals without tumors was 0.50 +/- 0.16, P = 0.025. We demonstrate that the expression of fecal PKC betaII and zeta may serve as a noninvasive marker for development of colon tumors. A sensitive technique for the detection of colon cancer is of importance since early diagnosis can substantially reduce mortality.      

宫颈病变液基细胞学筛查与组织病理学对照观察

目的　探讨液基薄层细胞学(ThinPrepCytologyTest, TCT)技术在妇科门诊人群宫颈病变筛查的准确性。方法　回顾性分析10 980例TCT,与组织学对比观察。结果　　TCTLSIL以上阳性率45. 7% ( 373 /817),组织学检查阳性率50. 1% ( 409 /817 ),两者统计学比较无显著性差异(P>0. 05 )。TCT诊断符合率LSIL75. 8% (191 /252),HSIL98. 1% (101 /103),SCC90. 9% (10 /11),AC85. 7% (6 /7)。鳞状上皮内病变诊断符合率HSIL与LSIL统计学比较有显著性差异(P<0. 01)。结论　液基细胞学检查是宫颈癌早期筛查的有效手段,加强制片技术及诊断质量控制对提高诊断的准确性有重要意义。     

Coexistence of benign phyllodes tumor and invasive ductal carcinoma in distinct breasts: case report

This report describes a rare case of coexistence of benign phyllodes tumor, which measured 9 cm in the right breast, and invasive ductal carcinoma of 6 cm in the left breast, synchronous and independent, in a 66-year-old patient. The patient underwent a bilateral mastectomy due to the size of both lesions. Such situations are rare and usually refer to the occurrence of ductal or lobular carcinoma in situ when associated with malignant phyllodes tumors, and more often in ipsilateral breast or intra-lesional.