Physiologically based pharmacokinetic model (PBPK), a mechanistic mathematic model, which can simulate the absorption, distribution, metabolism and excretion of drugs, is being more widely used in pharmaceutical research and development areas. This article reviews primarily the recent advances in the procedure of establishing a PBPK model, including specifying of the PBPK model structure, specification of the tissue model, writing of equations, set of model parameters, simulation and evaluation. Application significance, major challenges and future developments of PBPK model in pharmaceutical areas are also discussed.
Animals ; Biological Transport ; Computer Simulation ; Humans ; Models, Biological ; Pharmaceutical Preparations ; chemistry ; metabolism ; Pharmacokinetics ; Software ; Tissue Distribution

Objective To explore changes of local renin-angiotensin system(RAS)in renal tissue of rat during short-and mid-term tail suspension,as well as their relations with humoral regulation and renal function induced by real or simulated weightlessness.Methods 1-and 4-week(wk)tail-suspended rat model were used to simulate short-and mid-term weightlessness,respectively.Reverse transcriptase polymerase chain reaction(RT-PCR)was carried out to examine the mRNA expression of components of local RAS in renal tissue.Results Except for angiotensin Ⅱ receptor type 2(AT2),all of the other components of local RAS,including angiotensinogen(AGT),renin,angiotensin converting enzyme(ACE),angiotensin Ⅱ receptor type 1a(AT1a)and angiotensin Ⅱ receptor type 1b(AT1b),were found their expression in renal tissue of Sprague-Dawley rats.After 1 wk of tail suspension,mRNA expression of renin in renal tissue increased significantly(P

BACKGROUND: Cell apoptosis and ventricle reconstitution following myocardial infarction are of mutual cause-effect, and they cause vicious cycle. How to reduce the apoptosis events following myocardial infarction is one of keys to saving heart function.OBJECTIVE: To observe the effect of umbilical cord blood mesenchymal stem cell (UCBSMC) transplantation on remaining myocardial tissue of dogs with acute myocardial infarction.DESIGN: A randomized controlled observation.SETTING: Department of Cardiothoracic Surgery, Xinhua Hospital.MATERIALS: This study was carried out in the Central Laboratory of Xinhua Hospital from October 2005 to May 2007.Thirty-six adult hybrid dogs, male and female in half, were provided by the Animal Experimental Center of Xinhua Hospital.METHODS: Thirty-six dogs were divided into cell transplantation group and control group, with 18 dogs in each according to table of random digit. Mesenchymal stem cells were isolated from the umbilical cord blood of full-term pregnant hybrid dogs, cultured and amplified. Then, they were labeled with Laz gene, in vitro induced with 5-azacytidine, and transplanted into the dogs with acute myocardial infarction in the cell transplantation group. Rats in the control group were injected with the same amount of normal saline. Each dog was euthanized by anesthesia for harvesting myocardial specimen 1,4 and 8 weeks after transplantation.MAIN OUTCOME MEASURES: ① Remaining and apoptosis index detected by TUNEL method. ② Myocardial cell volume and histomorphology detected by confocal microscopy. ③ Histological change of myocardial collagen network detected by haematoxylin-basic fuchsin-picric acid staining.RESULTS: Thirty-six involved experimental dogs all entered the stage of final analysis. ①The apoptosis index in the cell transplantation group was significantly lower than that in the control group 1, 4 and 8 weeks after cell transplantation (P ＜0.05). ② Myocardial cell volume in the cell transplantation group 1, 4 and 8 weeks after cell transplantation was significantly larger than that in the control group (P ＜ 0.05). ③ Collagen fiber in the myocardial tissue of dogs in the cell transplantation group was arranged in order and regularly, and in contrast that in the control group was not, and fibers in the control group fused partially.CONCLUSION: UCBSMC transplantation reduces the apoptosis of myocardial cells, promotes the hypertrophy of remaining myocardial cells, regulates myocardial collagen network and improves heart function.

Objective To determine the level of interleukin (IL)-10 in sera and culture supernatants of CD4+CD25+T cells from children with atopic dermatitis (AD),and to evaluate its relationship with clinical course and severity of AD.Methods Totally,46 children with AD and 31 healthy controls were included in the study.All the patients were divided into 3 groups,i.e.,mild (n =10),moderate (n =16) and severe (n =20) group,according to severity scoring of atopic dermatitis (SCORAD) score.Venous blood samples were obtained from the patients and healthy controls.CD4+CD25+ regulatory T cells were separated from the blood samples by magnetic cell sorting (MACS) system in two steps and cultured in vitro.Enzyme linked immunosorbent assay (ELISA) was conducted to quantify the level of IL-10 in sera and culture supernatants of CD4+CD25 + T cells from these subjects.Analysis of variance was carried out to compare the level of supematant and serum IL-10 between the patients and controls,and Pearson correlation analysis to assess the relationship between the level of IL-10 and SCORAD score.Results The patients with mild,moderate and severe AD showed a similar serum IL-10 level compared with the healthy controls ((43.10 ± 25.07) pg/ml,(68.40 ± 36.65) pg/ml and (55.55 ± 41.97) pg/ml vs.(58.27 ± 36.84) pg/ml,all P ＞ 0.05).The level of supernatant IL-10 secreted by CD4+CD25+ T cells from the controls was significantly higher than that from the patients with severe AD ((55.15 ± 11.15) pg/ml vs.(27.25 ± 7.01) pg/ml,P ＜ 0.05),but similar to that from the patients with mild and moderate AD ((52.96 ± 11.69) pg/ml and (49.86 ± 9.18) pg/ml,respectively,both P ＞ 0.05).The level of secreted IL-10 was negatively correlated with SCORAD score (r =－0.757,P ＜ 0.01),whereas the serum level of IL-10 showed no statistical correlation with SCORAD score.Conclusion CD4+CD25+ T cells and IL-10 may be implicated in the development of AD.

Objective To evaluate the potential association of CD4+CD25+ T cells with alopecia areata.Methods Totally,this study enrolled 23 patients with progressive alopecia areata,25 patients with stable alopecia areata,and 25 healthy controls.Peripheral blood was isolated from these subjects followed by isolation of CD4+ CD25+ regulatory T cells,which were then cuhured with the presence of anti-CD3 and-CD28 monoclonal antibodies for four days.Subsequently,enzyme-linked immunosorbent assay was performed to measure the levels of interleukin (IL)-10 and transforming growth factor (TGF)-β1 in the culture supematant of these T cells.Results The levels of IL-10 and TGF-β1 were (31.68 ± 6.78) pg/ml and (32.29 ± 6.8) pg/ml respectively in the culture supernatant of CD4+CD25+ regulatory T cells from patients with progressive alopecia areata,significantly lower than those from the healthy controls ((57.34 ± 14.15) pg/ml and (57.43 ± 15.16) pg/ml,both P ＜ 0.05) and patients with stable alopecia areata ((52.56 ± 13.02) pg/ml and (61.75 ± 14.10) pg/ml,both P ＜ 0.05).However,no significant difference was observed in the supernatant levels of IL-10 or TGF-β1 between the healthy controls and patients with stable alopecia areata.Conclusions The secretion of IL-10 and TGF-β1 by CD4+CD25+ T cells is decreased in patients with progressive alopecia areata,which may contribute to the pathogenesis of alopecia areata.

Objective To report a case of Majocchi's granuloma induced by var. raubitschekii of Trichophyton rubrum, and to evaluate the relationship between deep and superficial fungal infection with genotyping technique. Methods The patient underwent physical, pathological and mycologic examination,which included microscopic observation, fungal culture, and urease reaction. The sequence of intertranscribed spacer (ITS) of rDNA was analysed by PCR and sequencing. Isolates from affected toes and tissue as well as one reference strain and six clinical strains of T. rubrum, were subjected to analysis of the tandem repeat subelement(TRS-1) in nontranscribed spacer(NTS)of rDNA by PCR. Results A 48-year-old female patient presented with a 2-month history of red papules and nodular lesions on the back, buttock and thigh,as well as a 3-year history of onychomycosis which had become more severe after a liver transplantation 9 months before. Pathological and mycologic examinations confirmed the diagnosis of Majocchi's granuloma. The pathogen was identified as var. raubitschekii of T. rubrum by microscopic examination, fungal culture, positive urease reaction and the sequence of ITS. As shown by the amplications of TRS-1 of NTS, the genotypes of strains from affected nails and tissue were identical, but differed from those of other clinical strains of T.rubrum. Conclusions There is a polymorphism in TRS-1 of rDNA NTS of T. rubrum, with the genotypes of isolates from affected nails and tissue being identical, which suggests they are of the same origin.

Bilirubin ; Child ; Duodenogastric Reflux ; diagnosis ; Esophageal Diseases ; diagnosis ; Esophagus ; metabolism ; Gastroesophageal Reflux ; diagnosis ; Humans

OBJECTIVETo analyze the clinical characteristics of elderly patients with spinal tuberculosis and explore its clinical effects with anti-TB drugs alone.

METHODSFrom January 2008 to July 2010, the data of 36 patients with spinal tuberculosis underwent conservative treatment of anti-TB drugs alone were analyzed. There were 19 males and 17 females with an average age of 73.5 years (ranged, 60 to 85). All patients were in the active phase with high ESR and CRP levels and were treated with 3HRZE/6-9HRE (course from 9 to 12 months). According to clinical symptoms, chemical examination, radiological image to adjust drug and depending on VAS score to evaluate pain.

RESULTSAll the patients were followed up from 8 to 24 months with an average of 15 months. Tuberculose of 31 patients healed after chemotherapy from 9 to 12 months and ESR and CRP recovered normally. Levofloxacin and para-amino salicylic acid were used in 4 cases because of 4 cases occurred drug fast for RFP or INH, after 15 months, their obtained healing. Symptom of 1 case got worse during chemotherapy, and surgical treatment were performed, after 3 months, ESR and CRP recovered normally, X-ray and CT showed spinal osteosclerosis and fusion without significant kyphosis and internal fixation loosening. Cobb angle was respectively(17.6+/-2.3) degrees, (18.1+/-2.7) degrees before treatment and last follow-up (P>0.05). MRI showed abscess was absorbed and spinal inflammation subsidised. VAS score was respectively 6.5+/-1.7, 1.4+/-0.5 before treatment and last follow-up (P<0.05). Seven patients had complications relating with drug adverse reaction,after discontinuation and treated with clinical symptom,the patients recovered normally.

CONCLUSIONAnti-TB drugs alone can obtain satisfactory effects in treating early senile spinal tuberculosis, but strict supervision and individual administration should not be disregardful.

Aged ; Aged, 80 and over ; Antitubercular Agents ; therapeutic use ; Female ; Humans ; Male ; Middle Aged ; Tuberculosis, Spinal ; diagnosis ; drug therapy

OBJECTIVE:To investigate the permeability of lomefloxacin through blood-pancreatic barrier in rats.METHO-DS:Lomefloxacin(20mg/kg body weight) was injected through caudal vein.At the given time points,the samples were collected.The concentrations of lomefloxacin in the serum,pancreatic tissue and liver tissue were measured by HPLC.RESULTS:The concentration-time profiles of lomefloxacin could be described as two-compartment model in rats.The peak concentrations in serum,pancreatic tissue and liver tissue were 65.550?g/ml,48.801?g/g and 84.121?g/g at 5 min post-injection respectively.Then the concentrations decreased quickly in all of them.Concentrations in pancreatic tissue were higher than those in serum at 10 min and even at 480 min post-injection.The permeation ratio (PR) through blood-pancreatic barrier was 0.744 at 5 min and rose to 3.817 at 480min.CONCLUSION:After intravenous injection,lomefloxacin can permeate blood-pancreatic barrier satisfactory,therefore it is worthy of being recommended for prevention and treatment of pancreatic infections.

Rats receiving unilateral nigral injection of 6 OHDA resulted in distinct reduction of DA (-88% ) , DOPAC(-80%) and HVA(-60%) in striatum of lesioned side, and the contents of 5HT and 5HIAA remained almost constant in comparison with that of contralateral striatum, suggesting selective lesion of nigrostriatal dopaminer-gic pathway induced by 6OHDA. Following 6OHDA lesion the rats exhibited circling behaviour after APO challenge. 1-Stephaniae ( 1-STP ) significantly antagonizied the action of APO in circling model in dose-dependent manner. Our results indicate that 1-STP possesses the ability to block DA receptor of central nervous system.