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1.
Zhonghua Yi Shi Za Zhi ; 54(1): 10-16, 2024 Jan 28.
Artigo em Chinês | MEDLINE | ID: mdl-38475680

RESUMO

By systematically examing through Longdan Xiegan Decoction in medical books of the past dynasties, it was found that the Longdan Xiegan Decoction recorded in Lan Shi Mi Cang mainly targeted men's genital odor at frist. After Xue Ji's addition and subtraction, the scope of the prescription was gradually generalized and expanded, and confusion its name, composition and source of the prescription appeared, which was particularly prominent in Jingyue Quanshu and Yifang Jijie.Doctors used to interpret this prescription from the perspective of viscera. In order to better understand the main treatment rules of Longdan Xiegan Decoction, it is necessary to change the perspective and reinterpreted it from the perspective of meridians.Attributing the symptoms of the perineum to Liver Meridian of Foot-Jueyin,hypochondriac pain, deafness and other symptoms to the Gallbladder Meridian of Foot-Shaoyang, and adding or subtracting herbs according to the specific conditions, is not only conducive to a comprehensive and in-depth understanding of the prescription to achieve accurate clinical syndrome differentiation and medication, but also prompts modern researchers to rethink the important role of meridian theory in the formation and development of the theoretical system of traditional Chinese medicine.


Assuntos
Medicamentos de Ervas Chinesas , Meridianos , Masculino , Humanos , Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Tradicional Chinesa , Prescrições
3.
Zhonghua Wai Ke Za Zhi ; 58(12): 942-946, 2020 Dec 01.
Artigo em Chinês | MEDLINE | ID: mdl-33249813

RESUMO

Objective: To explore the feasibility of Ponseti method in treatment of secondary clubfoot in young children with Tethered Cord Syndrome(TCS). Methods: The clinical data of 53 young children with clubfeet treated with Ponseti method from March 2014 to March 2017 at Department of Pediatric Orthopedics, the Third Affiliated Hospital of Zhengzhou University were analyzed retrospectively. These patients were divided into TCS group and Idiopathic group according to the etiology. There were 19 patients (33 feet) in TCS group,with an mean age of 2.8 months(range:0.2 to 24.0 months), including 13 males and 6 females, 5 patients with unilateral clubfeet and 14 patients with bilateral clubfeet. There were 34 patients (45 feet) in idiopathic group, with an mean age of 3.1 months(range: 0.1 to 21.0 months), including 18 males and 16 females, 23 patients with unilateral clubfeet and 11 patients with bilateral clubfeet. All the children received casts correction according to Ponseti method, and were followed up at 3 weeks, 3 months, 6 months and every 6 months after the Achilles tendon tenotomy or the last cast correction. Complications were recorded and therapeutic effect was evaluated of these children by Dimeglio Scoring System and the International Clubfoot Study Group (ICFSG) at the last follow-up. Independent t test, Mann-Witney U test or χ(2) test were used to compare the indicators of the two groups. Results: The number of plaster fixation in TCS group was (6.1±2.0) times, and that of idiopathic group was (4.8±1.0) times(t=3.482, P<0.01).In TCS group, 22 feet treated with Achilles tendon transection and that of idiopathic group was 40 feet(χ(2)=0.279, P=0.598). There were 18 cases recurrence in TCS group and 8 cases in Idiopathic group (t=11.149, P<0.01). In TCS group, 16 cases (27 feet) completed the initial correction, the success rate was 60.6% (27/33), 3 cases (6 feet) could not correct the deformity after 9 to 10 times of plaster fixation, and then underwent soft tissue release.In idiopathic group, 34 cases (45 feet) achieved initial correction after Ponseti treatment(χ(2)=6.488, P=0.011).At the last follow up, there were 5 cases (9 feet) in TCS group and 2 cases (2 feet) in idiopathic group underwent soft tissue release(χ(2)=6.110, P=0.013). The classification grade of ICFSG score of the two groups without soft tissue release were (2.1±0.6) and (1.8±0.7), the difference was not statistically significant (t=1.765, P=0.082). All the children had no skin ulceration, bedsores, skin allergy and other complications. Conclusion: Ponseti method is effective in the treatment of clubfoot secondary to TCS, and the functional recovery is similar to that of children with idiopathic clubfoot.


Assuntos
Pé Torto Equinovaro , Defeitos do Tubo Neural/complicações , Procedimentos Ortopédicos/métodos , Pré-Escolar , Pé Torto Equinovaro/etiologia , Pé Torto Equinovaro/cirurgia , Estudos de Viabilidade , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos , Resultado do Tratamento
4.
Eur Rev Med Pharmacol Sci ; 24(17): 8968-8977, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32964986

RESUMO

OBJECTIVE: Renal ischemia-reperfusion injury (IRI) is a clinically common issue and the resulting acute kidney injury (AKI) seriously threatens the patient's life. Therefore, prevention and treatment of renal IRI are the key to alleviating AKI in such patients. The purpose of this study was to explore the effects of VASPIN on mouse renal IRI and human renal proximal tubular epithelial cells (HK-2 cells) to provide a new direction for the treatment of clinical renal IRI. MATERIALS AND METHODS: C57/BL6 mice were used to construct a renal IRI model and recombinant mouse VASPIN was subcutaneously injected to determine whether VASPIN can alleviate renal IRI in mice by histological examination and detection of mouse urine and serum related indicators. In addition, HK-2 cells were cultured and an IRI model was constructed at the cellular level by hypoxia reoxygenation to examine the effect and mechanism of VASPIN on endoplasmic reticulum stress (ERS) in HK-2 cells. RESULTS: Results revealed that in VASPIN-treated mice, edema of renal tubular epithelial cells was significantly improved and renal injury markers netrin-1 and L-FAPB were decreased in urine. In addition, VASPIN also reduced the expression of inflammatory factors in mouse serum and the level of oxidative stress in kidney tissue. The expression of ERS-related molecules (GRP78, ATF6, caspase12, and CHOP) in HK-2 cells treated with VASPIN was significantly reduced and VASPIN decreased the expression of the pro-inflammatory factor HMGB1. Moreover, VASPIN promoted the activity of the Nrf2/ARE/HO-1 signaling pathway and inhibited the NF-кB signaling pathway by inhibiting HMGB1. CONCLUSIONS: VASPIN reduces inflammation and ERS levels in kidney tissue and attenuates renal IRI by activating the Nrf2/ARE/HO-1 signaling pathway and inhibiting the NF-кB signaling pathway via inhibition of HMGB1.


Assuntos
Adipocinas/metabolismo , Células Epiteliais/metabolismo , Proteína HMGB1/metabolismo , Inflamação/metabolismo , Túbulos Renais/metabolismo , Traumatismo por Reperfusão/metabolismo , Serpinas/metabolismo , Animais , Células Cultivadas , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL
5.
Zhonghua Yi Xue Za Zhi ; 98(30): 2418-2423, 2018 Aug 14.
Artigo em Chinês | MEDLINE | ID: mdl-30138987

RESUMO

Objective: To analyze the gene sequencing in eight patients with Glanzmann's thromboasthenia(GT), and combined with clinical manifestations and laboratory findings to investigate the molecular mechanism of GT. Methods: Eight patients who were diagnosed as GT based on platelet aggregation test and flow cytometry were enrolled, as well as 4 pedigrees. Next-generation sequencing was used to analyze all the exons and flanking sequences of αⅡ band ß3 gene and also platelet-type bleeding disorders related genes. Gene polymorphism was excluded by retrievaling HGMD and PubMed databases and relative literature. Mutations were confirmed by sanger sequencing. Results: All the eight patients had relatively normal platelet counts and coagulation profiles. But their platelet response to ADP was impaired, and their platelet response to ristocetin was relatively normal. Flow cytometry showed that of the 8 patients, platelet surface αⅡb/ß3 was lower than 5% of the normal value in 5 cases, and in 2 cases was 5% to 20% of normal value, and in 1 case there was no significant platelet surface αⅡb/ß3 reduction compared with normal level. Gene analysis revealed that five mutations in ITGA2B gene were identified, including c. 1750C>T(p.Arg584Ter), c.1882C>T(p.Arg628Ter), c.814G>C(p.Val272Leu), c.2333A>C(p.Gln778Pro), c.432G>A(p.Trp144Ter). Six mutations in ITGB3 gene, including c. 719G>A(p.Arg240Gln), c.2248C>T(p.Arg750Ter), c.1495T>C(p.Cys499Arg), c.1728delC(p.Ser577ProfsTer92), c.877C>T(p.Gln293Ter), c. 1260G>A were identified. In addition, mutations in genes such as RUNX1, HPS4, MYH9, ACTN1, HPS3 and SETBP1 were identified in patients with GT. Conclusions: Rather than homozygous mutations, heterozygous mutations, especially compound heterozygous mutations, are more common in patients with GT. The pathogenesis of GT may relate to gene mutations such as RUNX1 in addition to the ITGA2B gene and the ITGB3 gene.


Assuntos
Mutação , Trombastenia , Plaquetas , Proteínas de Transporte , Éxons , Genes Reguladores , Testes Genéticos , Heterozigoto , Homozigoto , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Linhagem , Testes de Função Plaquetária , Complexo Glicoproteico GPIIb-IIIa de Plaquetas , Polimorfismo Genético
6.
Eur Rev Med Pharmacol Sci ; 22(3): 715-720, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29461600

RESUMO

OBJECTIVE: To investigate the safety and effectiveness of the application of high-volume hemofiltration (HVHF) in children with sepsis combined with acute kidney injury. PATIENTS AND METHODS: A total of 76 child patients were enrolled and randomly divided equally (n=38) into control and the observation groups respectively. The control group received conventional volume hemofiltration (the ultrafiltration rate of 35-50 ml/kg/h), and the observation group received HVHF (50-100 ml/kg/h). RESULTS: The serum Interleukin-6 (IL-6), Tumor Necrosis Factor-a (TNF-α) and creatinine levels were significantly lower in the observation group than the control group at 6 h, 12 h, 24 h and 48 h of hemofiltration (p<0.05). The efficacy rate of treatment was improved. The mortality rate and incidence rate of complications were decreased, and the treatment course was significantly shortened (p<0.05). CONCLUSIONS: The application of HVHF in children with sepsis combined with acute kidney injury has a better safety and effectiveness.


Assuntos
Injúria Renal Aguda/terapia , Hemofiltração/métodos , Sepse/terapia , Criança , Pré-Escolar , Feminino , Humanos , Interleucina-6/sangue , Masculino , Fator de Necrose Tumoral alfa/sangue
7.
Eur Rev Med Pharmacol Sci ; 19(22): 4353-61, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26636523

RESUMO

OBJECTIVE: TM7SF4 (transmembrane 7 superfamily member 4) gene encodes a seven-pass transmembrane protein that is primarily expressed in dendritic cells called as dendritic cell-specific expressed seven transmembrane protein (DC-STAMP). This protein regulates immunological functions, osteoclastogenesis and myeloid differentiation. Although the roles of TM7SF4 have been currently studied on Paget's disease of bone and papillary thyroid cancers, it is unclear whether TM7SF4 plays a role in breast cancer. In current study, we investigated the expression of TM7SF4 in human breast cancer cell lines. MATERIALS AND METHODS: In this study, five breast cancer lines were cultured. Small hairpin RNA against TM7SF4 using a lentiviral vector was generated and transfected into MCF-7 breast cancer cells. Effects of down-regulating TM7SF4 in transfected cells were examined by Western blot, RT-PCR, apoptotic rate, colony formation, and cell cycle analyses. RESULTS: The results demonstrated that down-regulation of TM7SF4 led to a decrease in colony formation in MCF-7 cells compared to the control group. This is likely due to a decrease in proliferation and cell cycle and an increase in apoptosis. CONCLUSIONS: To our knowledge, our data demonstrate for the first time that TM7SF4 plays an essential role in regulating cell cycle progression in breast cancer.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Neoplasias da Mama/metabolismo , Ciclo Celular/fisiologia , Proteínas de Membrana/fisiologia , Apoptose/fisiologia , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Progressão da Doença , Feminino , Humanos , Células MCF-7 , RNA Interferente Pequeno/farmacologia , RNA Interferente Pequeno/fisiologia
8.
Clin Exp Dermatol ; 40(3): 309-12, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25545215

RESUMO

Fibroblastic rheumatism (FR) is a rare condition characterized by symmetrical polyarthritis and multiple cutaneous nodules. Approximately 30 cases have been reported worldwide to date. Laboratory tests are not particular useful to confirm the disease. Diagnosis is mainly dependent on the characteristic histopathological features: thickened collagen fibres with spindle-shaped cell proliferation in the skin lesion. We report a case of a 48-year-old Chinese man with typical clinical features of FR. In addition to the characteristic histopathological findings, multinuclear giant cell infiltration in skin lesions was detected, in this case. The evaluation of microelements revealed a raised blood lead level) of 129 µg/L (normal range 0-99 µg/L) These two features have never been described in the previous medical literature on FR. Thus, we propose that examining the infiltrated cells in detail in histopathological studies and inspecting the levels of lead and other microelements in the blood may increase our understanding of the pathogenesis of FR.


Assuntos
Células Gigantes/patologia , Chumbo/sangue , Doenças Reumáticas/sangue , Doenças Reumáticas/patologia , Dermatopatias/sangue , Dermatopatias/patologia , Colágeno/análise , Humanos , Masculino , Pessoa de Meia-Idade
9.
Environ Technol ; 30(11): 1103-9, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19947142

RESUMO

Kinetic studies on the photocatalytic degradation of aliphatic carboxylic acids were carried out in a slurry photoreactor with in-situ monitoring, employing artificial UV light as the source of energy and nano-TiO2 powder as the catalyst. The influences on the photocatalytic degradation such as the initial concentration of reactant (C0), catalyst dosage (CTiO2), UV intensity (Ia) and pH value have been investigated. Good agreement has been obtained between the value calculated by Langmuir-Freundlich-Hinshelwood (L-F-H) model and experimental data, with coefficient of multiple determination (R2) varying from 0.880 to 0.999. The L-F-H model has been proven to be feasible in describing the kinetic characteristic of the photocatalytic degradation of aliphatic carboxylic acids. Moreover, the apparent reaction rate constant (k) of the photocatalytic degradation of dicarboxylic acids is higher than that of monocarboxylic acids with the same carbon atoms. This shows that the photocatalytic degradation rate is favoured by different chemical structure.


Assuntos
Ácidos Carboxílicos/química , Ácidos Graxos/química , Modelos Químicos , Titânio/química , Poluentes da Água/química , Purificação da Água/métodos , Água/química , Ácidos Carboxílicos/efeitos da radiação , Catálise , Simulação por Computador , Ácidos Graxos/efeitos da radiação , Cinética , Luz , Fotoquímica/métodos , Suspensões , Titânio/efeitos da radiação , Raios Ultravioleta , Poluentes da Água/efeitos da radiação
10.
Br J Pharmacol ; 153(6): 1203-13, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18204477

RESUMO

BACKGROUND AND PURPOSE: The protoberberine alkaloid berberine has been reported to inhibit colonic Cl(-) secretion. However, it is not known if other protoberberine alkaloids share these effects. We have therefore selected another protoberberine alkaloid, palmatine, to assess its effects on active ion transport across rat colonic epithelium. EXPERIMENTAL APPROACH: Rat colonic mucosa was mounted in Ussing chambers and short circuit current (I (SC)), apical Cl(-) current and basolateral K(+) current were recorded. Intracellular cAMP content was determined by an enzyme immunoassay. Intracellular Ca(2+) concentration was measured with Fura-2 AM. KEY RESULTS: Palmatine inhibited carbachol-induced Ca(2+)-activated Cl(-) secretion and the carbachol-induced increase of intracellular Ca(2+) concentration. Palmatine also inhibited cAMP-activated Cl(-) secretion induced by prostaglandin E(2) (PGE(2)) or forskolin. Palmatine prevented the elevation of intracellular cAMP by forskolin. Determination of apical Cl(-) currents showed that palmatine suppressed the forskolin-stimulated, apical cAMP-activated Cl(-) current but not the carbachol-stimulated apical Ca(2+)-activated Cl(-) current. Following permeabilization of apical membranes with nystatin, we found that palmatine inhibited a carbachol-stimulated basolateral K(+) current that was sensitive to charybdotoxin and resistant to chromanol 293B. However, the forskolin-stimulated basolateral K(+) current inhibited by palmatine was specifically blocked by chromanol 293B and not by charybdotoxin. CONCLUSIONS AND IMPLICATIONS: Palmatine attenuated Ca(2+)-activated Cl(-) secretion through inhibiting basolateral charybdotoxin-sensitive, SK4 K(+) channels, whereas it inhibited cAMP-activated Cl(-) secretion by inhibiting apical CFTR Cl(-) channels and basolateral chromanol 293B-sensitive, KvLQT1 K(+) channels.


Assuntos
Alcaloides de Berberina/farmacologia , Cloretos/metabolismo , AMP Cíclico/metabolismo , Canais de Potássio Cálcio-Ativados/efeitos dos fármacos , Animais , Transporte Biológico Ativo/efeitos dos fármacos , Cálcio/metabolismo , Charibdotoxina/farmacologia , Colo/efeitos dos fármacos , Colo/metabolismo , Técnicas In Vitro , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Masculino , Canais de Potássio Cálcio-Ativados/metabolismo , Ratos , Ratos Wistar
11.
J Oral Rehabil ; 34(5): 383-8, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17441879

RESUMO

A series of Ag-Hg and Ag-Pd-Hg phases have been prepared by immersion in mercury and subsequent heat treatment of pure Ag and a series of Ag-Pd alloys. Phase transitions, along with the changes involved in morphology and chemistry, are investigated. Experimental results indicate that when mercury-immersed Ag discs are heat-treated at 90 degrees C for 12 h, large (>50 microm) crystals with Ag/Hg atomic ratios close to those of stoichiometric AgHg(2) form on the Ag surface. Heat treatment for 36 h causes these crystals to disintegrate into smaller (majority <10 microm) Ag(2)Hg(3) (gamma(1)) crystals. After 60 h, the stoichiometric gamma(1) crystals further breakdown into even smaller stoichiometric AgHg(beta(1)) crystals. The oft-referenced beta(1) phase Ag(1.1)Hg(0.9) is not supported in the present study. Addition of Pd to Ag has a dramatic effect on the morphology of the gamma(1) phase. With more addition of Pd, large-faceted and elongated gamma(1) crystals tend to grow in the midst of smaller matrix gamma(1) crystals. All three different Pd-containing crystals have (Ag + Pd)/Hg ratios very close to those of the stoichiometric gamma(1) phase, indicating that added Pd tends to replace Ag, rather than Hg, in the gamma(1) phase.


Assuntos
Ligas Dentárias/química , Paládio/química , Compostos de Prata/química , Prata/química , Temperatura Alta , Imersão , Mercúrio , Microscopia Eletrônica de Varredura , Propriedades de Superfície , Difração de Raios X/métodos
12.
Gene Ther ; 12(12): 999-1010, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15789061

RESUMO

Type 1 T cells are the major components in antitumor immunity. The lack of efficient CD8(+) cytotoxic T (Tc) cell infiltration of tumors is a major obstacle to adoptive Tc-cell therapy. We have previously demonstrated that adenovirus (AdV)-mediated transgene lymphotactin (Lptn) expression by intratumoral AdVLptn injection and intravenous CD4(+) helper T (Th) cell transfer can enhance Tc-cell tumor infiltration and eradication of early stage tumors (5 mm in diameter). In this study, we generated ovalbumin (OVA)-specific Tc1 and Th1 cells in vitro by incubation of OVA-pulsed dendritic cells with naive T cells from T-cell receptor (TCR) transgenic OT I and OT II mice. We then investigated the potential synergy of Th1 help effect and Lptn transgene expression in Tc1-cell therapy of well-established OVA-expressing EG7 solid tumors (7 mm in diameter). Our data showed that a combined adoptive T-cell therapy of Th1 (2.5 x 10(6) cells per mouse) and Tc1 (5 x 10(6) cells per mouse) resulted in regression of all eight (100%) transgene Lptn expressed EG7 tumors, which is significantly higher than four from eight (50%) in AdVLptn/Tc1 group and two from eight (25%) in Tc1/Th1 group (P < 0.05). The amount of transferred Tc1 cells detected in Lptn-expressed tumors with Th1 treatment is 0.72%, which is significantly higher than those of AdVLptn (0.22%), Th1 (0.41%) and the control AdVpLpA (0.09%) treatment groups (P < 0.05). Enhanced Tc1 tumor localization may be derived from the chemotactic effect of Lptn and the proliferative effect of Th1 and Lptn. This novel therapeutic strategy with enhancement of Tc1 tumor localization in the therapy of well-established tumors may become a tool of considerable conceptual interest in the implementation of future clinical objectives.


Assuntos
Transferência Adotiva/métodos , Linfócitos T CD8-Positivos/imunologia , Terapia Genética/métodos , Linfocinas/genética , Neoplasias Experimentais/terapia , Sialoglicoproteínas/genética , Células Th1/imunologia , Adenoviridae/genética , Animais , Linhagem Celular Tumoral , Proliferação de Células , Quimiocinas C , Quimiotaxia de Leucócito , Feminino , Expressão Gênica , Vetores Genéticos/administração & dosagem , Linfócitos/imunologia , Linfócitos do Interstício Tumoral , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Modelos Animais , Neoplasias Experimentais/imunologia , Ovalbumina/imunologia , Receptores de Antígenos de Linfócitos T/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução Genética/métodos , Transgenes
14.
Pediatr Surg Int ; 13(7): 494-6, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9716677

RESUMO

Ten cases of choledochal cyst (CC) were treated by biliary-appendicoduodenostomy. The follow-up comprised a patient interview, ultrasonography (US), and single-proton ejected computerized tomography (SPECT) scanning. In all cases an anti-reflux submucosal tunnel was added to the distal appendico-duodenostomy; all showed an uneventful postoperative course. All the dilated intrahepatic bile ducts had normalized on B-US postoperatively. Four children under went SPECT examination; all of them had patent neo-bile ducts. In the authors' opinion: (1) Anastomosing the cecal end of the appendix to the common hepatic duct seemed more favorable than the other way around, because the cecal end could be easily trimmed to the size of the common hepatic duct, which was more or less dilated in the presence of a CC; (2) It is necessary to add a submucosal tunnel to the distal appendicoduodenostomy to achieve a more reliable anti-reflux effect; and (3) Transposing the vascularized appendix through the retro-transverse colon simplified the procedure and might reduce the risk of retroperitoneal complications if bile leakage should occur.


Assuntos
Apêndice/cirurgia , Procedimentos Cirúrgicos do Sistema Biliar/métodos , Cisto do Colédoco/cirurgia , Pré-Escolar , Cisto do Colédoco/diagnóstico , Feminino , Seguimentos , Humanos , Masculino , Tomografia Computadorizada de Emissão de Fóton Único
15.
Biophys J ; 75(2): 1076-83, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9675209

RESUMO

Using a hard sphere model and numerical calculations, the effect of the hydration force between a conical tip and a flat surface in the atomic force microscope (AFM) is examined. The numerical results show that the hydration force remains oscillatory, even down to a tip apex of a single water molecule, but its lateral extent is limited to a size of a few water molecules. In general, the contribution of the hydration force is relatively small, but, given the small imaging force ( approximately 0.1 nN) typically used for biological specimens, a layer of water molecules is likely to remain "bound" to the specimen surface. This water layer, between the tip and specimen, could act as a "lubricant" to reduce lateral force, and thus could be one of the reasons for the remarkably high resolution achieved with contact-mode AFM. To disrupt this layer, and to have a true tip-sample contact, a probe force of several nanonewtons would be required. The numerical results also show that the ultimate apex of the tip will determine the magnitude of the hydration force, but that the averaged hydration pressure is independent of the radius of curvature. This latter conclusion suggests that there should be no penalty for the use of sharper tips if hydration force is the dominant interaction between the tip and the specimen, which might be realizable under certain conditions. Furthermore, the calculated hydration energy near the specimen surface compares well with experimentally determined values with an atomic force microscope, providing further support to the validity of these calculations.


Assuntos
Microscopia de Força Atômica/métodos , Calibragem , Modelos Estruturais , Modelos Teóricos , Reprodutibilidade dos Testes
16.
J Microsc ; 182(Pt 2): 106-13, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8683559

RESUMO

A computer model based on the elastic properties of rubber is introduced for the evaluation of the lateral resolution in atomic force microscopy of deformable specimens. The computational results show that, if the full width at half-height can be defined as the lateral resolution, it is continuously improved at greater probe forces, at the expense of a reduced molecular height, In fact, even for a probe that is bigger than the molecule, the real size of the molecule can be 'recovered' at about 25% compression. This result demonstrates that for a better lateral resolution, a greater probe force can be beneficial, provided that the molecule is not moved or damaged and the response remains elastic. Measurements on isolated low-density lipoproteins (LDL) show that with 26% vertical compression, the lateral size measured in atomic force microscopy is only 72% of the value predicted by a simple convolution, and is only slightly larger (approximately 13%) than the known size of LDL. Therefore, the results on LDL provide a direct support for the conclusions of the computational model.


Assuntos
Simulação por Computador , Microscopia de Força Atômica , Elasticidade , Modelos Moleculares , Borracha
19.
Cancer ; 71(10): 2941-5, 1993 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-7683965

RESUMO

The clinicopathologic characteristics of 104 hepatectomy samples from female patients with primary hepatocellular carcinoma (PHC) were compared with similar samples from 900 male patients with primary hepatocellular carcinoma; results of this comparison were studied. The male-to-female ratio was 8.7:1. The mean age of female patients with PHC was 46.2 years, which was approximately 3 years younger (49.1 years) than that of male patients with PHC. The frequency of associated liver cirrhosis (LC) was 49% in women with PHC and 68.2% in men with PHC (P < 0.01). The mean age of the female patients without LC was 43.2 years, more than 4 years younger (47.9 years) than that of the male patients. The mean ages of female and male patients with LC were 49.1 years and 49.8 years, 6 and 2 years older than that of their corresponding groups without LC, respectively. The positive rates of serum hepatitis B surface antigen (HBsAg) were 70.8% in the men and 59.7% in the women. The 5-year postoperative survival rates were 50% in the women and 25.7% in the men (P < 0.01). It is suggested that the development of PHC in women appears at a younger age than that of PHC in men in China and usually is associated with a lower frequency of LC and a more satisfactory postoperative prognosis.


Assuntos
Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Adulto , Fatores Etários , Carcinoma Hepatocelular/fisiopatologia , China , Feminino , Hepatectomia , Antígenos de Superfície da Hepatite B/análise , Humanos , Neoplasias Hepáticas/fisiopatologia , Masculino , Pessoa de Meia-Idade , Prognóstico , alfa-Fetoproteínas/metabolismo
20.
FEBS Lett ; 311(1): 71-4, 1992 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-1327876

RESUMO

Phorbol 12-myristate 13-acetate (100 nM), a potent protein kinase C and macrophage activator, has a biphasic affect on 25(OH)D3-1 alpha-hydroxylase activity in synovial fluid macrophages from arthritis patients. After 5 h, 1 alpha, 25(OH)D3 synthesis fell from 5.2 +/- 0.1 to 1.6 +/- 0.2 pmol/h per 10(6) cells, however, after 24 h and 48 h, synthesis increased to 17.4 +/- 0.3 and 22.3 +/- 1.4 pmol/h per 10(6) cells, respectively. Although an independent short-term mechanism is suggested, protein kinase C may promote macrophage activation, thus increasing long-term 25(OH)D3-1 alpha-hydroxylase expression. Intracellular calcium and cAMP are unlikely to activate the enzyme, since 0.1 microM of the calcium ionophore, A23187, and 1 mM dibutyryl-cAMP inhibited synthesis by 87% and 79%, respectively, after 24 h.


Assuntos
Artrite/metabolismo , Calcitriol/biossíntese , Macrófagos/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Artrite Gotosa/metabolismo , Artrite Reumatoide/metabolismo , Bucladesina/farmacologia , Calcimicina/farmacologia , Células Cultivadas , Relação Dose-Resposta a Droga , Humanos , Macrófagos/efeitos dos fármacos , Líquido Sinovial/citologia
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