Efficacy of different surgical treatments for management of anal fistula: a network meta-analysis.

PURPOSE: Currently, the anal fistula treatment which optimises healing and preserves bowel continence remains unclear. The aim of our study was to compare the relative efficacy of different surgical treatments for AF through a network meta-analysis. METHODS: Systematic searches of MEDLINE, EMBASE and CENTRAL databases up to October 2022 identified randomised controlled trials (RCTs) comparing surgical treatments for anal fistulae. Fistulae were classified as simple (inter-sphincteric or low trans-sphincteric fistulae crossing less than 30% of the external anal sphincter (EAS)) and complex (high trans-sphincteric fistulae involving more than 30% of the EAS). Treatments evaluated in only one trial were excluded from the primary analyses to minimise bias. The primary outcomes were rates of success in achieving AF healing and bowel incontinence. RESULTS: Fifty-two RCTs were included. Of the 14 treatments considered, there were no significant differences regarding short-term (6 months or less postoperatively) and long-term (more than 6 months postoperatively) success rates between any of the treatments in patients with both simple and complex anal fistula. Ligation of the inter-sphincteric fistula tract (LIFT) ranked best for minimising bowel incontinence in simple (99.1% of comparisons; 3 trials, n = 70 patients) and complex anal fistula (86.2% of comparisons; 3 trials, n = 102 patients). CONCLUSIONS: There is insufficient evidence in existing RCTs to recommend one treatment over another regarding their short and long-term efficacy in successfully facilitating healing of both simple and complex anal fistulae. However, LIFT appears to be associated with the least impairment of bowel continence, irrespective of AF classification.

Mobile health technology for remote home monitoring after surgery: a meta-analysis.

BACKGROUND: Mobile health (mHealth) technology has been proposed as a method of improving post-discharge surveillance. Little is known about how mHealth has been used to track patients after surgery and whether its use is associated with differences in postoperative recovery. METHODS: Three databases (PubMed, MEDLINE and the Cochrane Central Registry of Controlled Trials) were searched to identify studies published between January 1999 and February 2021. Mobile health was defined as any smartphone or tablet computer capable of electronically capturing health-related patient information and transmitting these data to the clinical team. Comparable outcomes were pooled via meta-analysis with additional studies compiled via narrative review. The quality of each study was assessed based on Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criteria. RESULTS: Forty-five articles met inclusion criteria. While the majority of devices were designed to capture general health information, others were specifically adapted to the expected outcomes or potential complications of the index procedure. Exposure to mHealth was associated with fewer emergency department visits (odds ratio 0.42, 95 per cent c.i. 0.23 to 0.79) and readmissions (odds ratio 0.47, 95 per cent c.i. 0.29 to 0.77) as well as accelerated improvements in quality of life after surgery. There were limited data on other postoperative outcomes. CONCLUSION: Remote home monitoring via mHealth is feasible, adaptable, and may even promote more effective postoperative care. Given the rapid expansion of mHealth, physicians and policymakers need to understand these technologies better so that they can be integrated into high-quality clinical care.

A systematic review was performed to determine how mobile health (mHealth) technology is being used to track surgical patients after hospital discharge, and whether exposure to mHealth is associated with differences in postoperative recovery. Remote home monitoring via mHealth is feasible and flexible enough to meet the demands of a variety of patients and clinical teams. Exposure to mHealth also appears to be associated with a reduction in both emergency department visits and hospital readmissions as well as accelerated improvements in quality of life. mHealth represents an important next step in postoperative surveillance, although better performance data, targeted incentives and clearer guidelines are still needed.

Does Flexoelectricity Drive Triboelectricity?

The triboelectric effect, charge transfer during sliding, is well established but the thermodynamic driver is not well understood. We hypothesize here that flexoelectric potential differences induced by inhomogeneous strains at nanoscale asperities drive tribocharge separation. Modeling single asperity elastic contacts suggests that nanoscale flexoelectric potential differences of ±1-10 V or larger arise during indentation and pull-off. This hypothesis agrees with several experimental observations, including bipolar charging during stick slip, inhomogeneous tribocharge patterns, charging between similar materials, and surface charge density measurements.

Hyperactive cyclic motor activity in the distal colon after colonic surgery as defined by high-resolution colonic manometry.

BACKGROUND: Recovery after colonic surgery is invariably delayed by disturbed gut motility. It is commonly assumed that colonic motility becomes quiescent after surgery, but this hypothesis has not been evaluated rigorously. This study quantified colonic motility through the early postoperative period using high-resolution colonic manometry. METHODS: Fibre-optic colonic manometry was performed continuously before, during and after surgery in the left colon and rectum of patients undergoing right hemicolectomy, and in healthy controls. Motor events were characterized by pattern, frequency, direction, velocity, amplitude and distance propagated. RESULTS: Eight patients undergoing hemicolectomy and nine healthy controls were included in the study. Colonic motility became markedly hyperactive in all operated patients, consistently dominated by cyclic motor patterns. Onset of cyclic motor patterns began to a minor extent before operation, occurring with increasing intensity nearer the time of surgery; the mean(s.d.) active duration was 12(7) per cent over 3 h before operation and 43(17) per cent within 1 h before surgery (P = 0.024); in fasted controls it was 2(4) per cent (P < 0·001). After surgery, cyclic motor patterns increased markedly in extent and intensity, becoming nearly continuous (active duration 94(13) per cent; P < 0·001), with peak frequency 2-4 cycles per min in the sigmoid colon. This postoperative cyclic pattern was substantially more prominent than in non-operative controls, including in the fed state (active duration 27(20) per cent; P < 0·001), and also showed higher antegrade velocity (P < 0·001). CONCLUSION: Distal gut motility becomes markedly hyperactive with colonic surgery, dominated by cyclic motor patterns. This hyperactivity likely represents a novel pathophysiological aspect of the surgical stress response. Hyperactive motility may contribute to gut dysfunction after surgery, potentially offering a new therapeutic target to enhance recovery.

The Americleft Project: A Proposed Expanded Nasolabial Appearance Yardstick for 5- to 7-Year-Old Patients With Complete Unilateral Cleft Lip and Palate (CUCLP).

OBJECTIVE: To develop a yardstick of reference photographs for nasolabial appearance assessments of 5- to 7-year-old patients with complete unilateral cleft lip and palate (CUCLP). DESIGN: Blind retrospective analysis of clinical records and comparison to historical controls. PATIENTS: Subjects were two groups of 6- to 12-year-olds (n = 124 and n = 135) and one group of 5- to 7-year-olds (n = 149) with nonsyndromic CUCLP from three previous Americleft studies, including cohorts from seven different cleft/craniofacial centers. INTERVENTIONS: All patients received the infant management protocols of their respective centers. Eleven trained and calibrated judges (five participated in all three studies) did blind ratings of nasolabial appearance using the Asher-McDade method. MAIN OUTCOME MEASURES: Patients receiving the most consistent ratings between judges, selected first from the groups of 6- to 12-year-olds, were used to create a pilot yardstick for eventual use in the third study of 5- to 7-year-olds. For each of the Asher-McDade categories, 8 of the 5- to 7-year-old patients receiving the most consistent scores between raters were ranked by 10 judges for a final elimination to leave three per category. RESULTS: Using this method of successive changes in rating methods, a new reference yardstick for nasolabial appearance rating was established and linked to the original Asher-McDade method as well as the single examples in a previously published yardstick for patients with CUCLP. Pilot testing using the yardstick improved reliabilities. CONCLUSIONS: Use of an expanded nasolabial yardstick of reference photographs representative of the range of possibilities of each of the five Asher-McDade categories is now available to see if reliability of these ratings can be improved.

Localization of the gene for Cowden disease to chromosome 10q22-23.

Cowden disease (CD) (MIM 158350), or multiple hamartoma syndrome, is a rare autosomal dominant familial cancer syndrome with a high risk of breast cancer. Its clinical features include a wide array of abnormalities but the main characteristics are hamartomas of the skin, breast, thyroid, oral mucosa and intestinal epithelium. The pathognomonic hamartomatous features of CD include multiple smooth facial papules, acral keratosis and multiple oral papillomas. The pathological hallmark of the facial papules are multiple trichilemmomas. Expression of the disease is variable and penetrance of the dermatological lesions is assumed to be virtually complete by the age of twenty. Central nervous system manifestations of CD were emphasized only recently and include megalencephaly, epilepsy and dysplastic gangliocytomas of the cerebellum (Lhermitte-Duclos disease, LDD). Early diagnosis is important since female patients with CD are at risk of developing breast cancer. Other lesions include benign and malignant disease of the thyroid, intestinal polyps and genitourinary abnormalities. To localize the gene for CD, an autosomal genome scan was performed. A total of 12 families were examined, resulting in a maximum lod score of 8.92 at theta = 0.02 with the marker D10S573 located on chromosome 10q22-23.

Regulating the retention of T-cell receptor alpha chain variants within the endoplasmic reticulum: Ca(2+)-dependent association with BiP.

Immunoglobulin heavy chain binding protein (BiP, GRP 78) coprecipitates with soluble and membrane-associated variants of the T-cell antigen receptor alpha chain (TCR-alpha) which are stably retained within the ER. Chelation of Ca2+ during solubilization of cells leads to the dissociation of BiP from the TCR-alpha variants, which is dependent upon the availability of Mg2+ and hydrolyzable ATP; this suggests that Ca2+ levels can serve to modulate the association/dissociation of these proteins with BiP. In vivo treatment of cells expressing either the soluble or membrane-anchored TCR-alpha variants with the Ca2+ ionophore, A23187, or an inhibitor of an ER Ca(2+)-ATPase, thapsigargin, or the membrane-permeant Ca2+ chelator BAPTA-AM, results in the redistribution of these proteins out of the ER and their subsequent secretion or cell surface expression. Under the same assay conditions, no movement of BiP out of the ER is observed. Taken together, these observations indicate that decreased Ca2+ levels result in the dissociation of a protein bound to BiP, leading to its release from ER retention. These data suggest that the intracellular fate of newly synthesized proteins stably associated with BiP can be regulated by Ca2+ levels in the ER.

Expression of T cell antigen receptor heterodimers in a lipid-linked form.

The interaction of the T cell receptor for antigen (TCR) with its antigen-major histocompatibility complex ligand is difficult to study because both are cell surface multimers. The TCR consists of two chains (alpha and beta) that are complexed to the five or more nonpolymorphic CD3 polypeptides. A soluble form of the TCR was engineered by replacing the carboxyl termini of alpha and beta with signal sequences from lipid-linked proteins, making them susceptible to enzymatic cleavage. In this manner, TCR heterodimers can be expressed independently of the CD3 polypeptides and in significant quantities (0.5 milligram per week). This technique seems generalizable to biochemical and structural studies of many other cell surface molecules as well.

A calcium ionophore-inducible cellular promoter is highly active and has enhancerlike properties.

We examined the regulatory/promoter sequence of a calcium ionophore-inducible gene isolated from the rat genome. Whereas the promoter of this ubiquitously expressed gene is active under noninduced conditions, after induction by calcium ionophore A23187 this promoter is 10- to 25-fold more active than the simian virus 40 early promoter, as measured by chloramphenicol acetyltransferase activities. Within this regulatory/promoter region, we have identified a DNA fragment with enhancer-like properties immediately 5' to the TATA sequence. This 291-nucleotide fragment acts in cis to enhance expression of the neomycin phosphotransferase (neo) gene driven by the herpes simplex virus thymidine kinase promoter in an orientation-independent manner. In addition, this fragment can confer A23187 inducibility to the neo gene and effectively compete for positive regulatory factors involved in A23187 induction. Sequence analysis of this promoter reveals homology with viral core enhancer sequences, and the apparent organization of direct repeat domains is similar to those observed in viral enhancers.

Whole-Organism Cellular Pathology: A Systems Approach to Phenomics.

Phenotype is defined as the state of an organism resulting from interactions between genes, environment, disease, molecular mechanisms, and chance. The purpose of the emerging field of phenomics is to systematically determine and measure phenotypes across biology for the sake of understanding. Phenotypes can affect more than one cell type and life stage, so ideal phenotyping would include the state of every cell type within the context of both tissue architecture and the whole organism at each life stage. In medicine, high-resolution anatomic assessment of phenotype is obtained from histology. Histology's interpretative power, codified by Virchow as cellular pathology, is derived from its ability to discern diagnostic and characteristic cellular changes in diseased tissues. Cellular pathology is observed in every major human disease and relies on the ability of histology to detect cellular change in any cell type due to unbiased pan-cellular staining, even in optically opaque tissues. Our laboratory has shown that histology is far more sensitive than stereomicroscopy for detecting phenotypes in zebrafish mutants. Those studies have also shown that more complete sampling, greater consistency in sample orientation, and the inclusion of phenotypes extending over longer length scales would provide greater coverage of common phenotypes. We are developing technical approaches to achieve an ideal detection of cellular pathology using an improved form of X-ray microtomography that retains the strengths and addresses the weaknesses of histology as a screening tool. We are using zebrafish as a vertebrate model based on the overlaps between zebrafish and mammalian tissue architecture, and a body size small enough to allow whole-organism, volumetric imaging at cellular resolution. Automation of whole-organism phenotyping would greatly increase the value of phenomics. Potential societal benefits would include reduction in the cost of drug development, a reduction in the incidence of unexpected severe drug and environmental toxicity, and more rapid elucidation of the contributions of genes and the environment to phenotypes, including the validation of candidate disease alleles identified in population and personal genetics.

Alternative splicing of the RBP1 gene clusters in an internal exon that encodes potential phosphorylation sites.

We have isolated cDNA and genomic clones for the human retinoblastoma binding protein 1 (RBP1) gene, and have identified alternative splicing of RBP1 clustered within a 207-nucleotide internal exon. Three of the predicted RPB1 peptides share amino-terminal and carboxy-terminal domains, while a fourth species encodes a distinct carboxy-terminal domain. Functional analysis of these peptides demonstrated that they are capable of precipitating retinoblastoma (RB) protein in vitro from K562 cell lysates, but cannot bind to mutant RB protein. However, each of the RBP1 peptides differed within an internal exon that contains potential casein kinase II and p34cdc2 phosphorylation sites. Immunoblot analysis using polyclonal alpha-RBP1 antiserum revealed that the RBP1 protein is expressed in a wide range of cell lines of differing histologic type and migrates on sodium dodecyl sulfate-polyacrylamide gel electrophoresis predominantly as a 200-kDa protein. Immunohistochemical analysis using the alpha-RBP1 antiserum demonstrated a distinct nuclear staining pattern that was eliminated when the antiserum was preabsorbed with RBP1 peptide. The RBP1 gene encodes a widely expressed 200-kDa nuclear protein and undergoes alternative splicing that predicts a family of RB-binding peptides.

Absence of germline p53 mutations in familial lymphoma.

p53, a tumor suppressor gene, is frequently mutated in sporadic human cancer, and inherited mutations in p53 predispose to the early onset of cancer. p53 mutations occur frequently in sporadic lymphoma, and, in mice deficient for p53, lymphoma is the most common type of malignancy. Families with an increased incidence of lymphoma have been described, suggesting an inherited predisposition to lymphoma in these circumstances. To determine whether the predisposition to lymphoma in these families results from germline mutations in p53, we analysed exons 4-11 of the p53 gene in 35 individuals from 19 lymphoma-prone kindreds. We found no germline p53 mutations in any of the individuals tested. However, p53 expression assessed by immunohistochemistry, which suggests mutation, was observed in 35% of the tumor samples from the familial Hodgkin's disease cases and in 13% of the familial non-Hodgkin's lymphoma cases. These results suggest that p53 mutations do not play a critical role in heritable susceptibility to lymphoma. p53 may act by different, non-mutation related mechanisms in this setting, or be involved in late events in the pathogenesis of these tumors.

Platelet-activating factor induced calcium mobilization and phosphoinositide metabolism in cultured bovine cerebral microvascular endothelial cells.

Platelet-activating factor (PAF) is a powerful lipid autacoid with a variety of biological activities. More and more evidence suggests that PAF might play an important role in modulation of cerebrovascular system function, particularly during ischemia-induced cerebrovascular damage. However, the mechanisms involved in PAF actions on cerebrovascular or other brain cells are virtually unknown. Therefore, this study was designed to investigate PAF receptor-mediated cellular signal transduction in bovine cerebral microvascular endothelial (CME) cells with the aid of a potent PAF antagonist, WEB 2086. PAF induced an immediate and concentration-dependent increase in [Ca2+]i with an EC50 of 4.75 nM. PAF-induced [Ca2+]i mobilization was inhibited by PAF antagonist WEB 2086, in a dose-dependent manner (IC50 = 15.53 nM). The calcium channel blockers diltiazem (10 microM) and verapamil (10 microM) had no effect on the PAF-induced increase in [Ca2+]i, but depletion of Ca2+ from the incubation buffer caused a 45.26% reduction of PAF-induced [Ca2+]i elevation. PAF stimulated phosphoinositide metabolism in a dose-dependent manner with an EC50 of 12.4 nM for IP3 formation, which was also inhibited by the PAF antagonist WEB 2086 in a dose-dependent manner with IC50 value of 16.97 nM for IP3 production. These data indicate that bovine CME cells respond to biologically relevant concentrations of PAF and this response involves activation of phospholipase C and increase in [Ca2+]i via specific PAF receptors. Our results may contribute to further understanding of the mechanism behind PAF actions on cerebrovascular cells.

Expression of growth differentiation factor-5 and bone morphogenic protein-7 in intraocular osseous metaplasia.

BACKGROUND/AIMS: Intraocular bone is seen in a wide spectrum of ocular disorders. The pathogenetic mechanisms of bone formation in the eye are unclear. Growth differentiation factor-5 (GDF-5), bone morphogenic protein-7 (BMP-7), and transforming growth factor beta-1 (TGF beta1) are multifunctional cytokines that have important roles in bone formation. Immunohistochemistry was used to localise GDF-5, BMP-7, and TGF beta1 in the human eye to determine their role in intraocular bone formation. METHODS: Paraffin embedded sections from human eyes included fetal eyes (n = 5), normal adult eyes (n = 4), eyes with osseous metaplasia (n = 8), and eyes with focal fibrous metaplasia of the retinal pigment epithelium (RPE) without osseous metaplasia (n = 2). Immunohistochemistry was performed using indirect immunofluorescence with antibodies to GDF-5, BMP-7, and TGF beta1. The staining intensity was evaluated semiquantitatively in the RPE, retina, ciliary epithelium, and cornea; and analysed statistically. RESULTS: When compared with normal adult eyes, which showed no RPE immunoreactivity, the RPE metaplasia surrounding areas of osseous metaplasia showed mild GDF-5 and moderate BMP-7 (p = 0.004) intracytoplasmic immunoreactivity. In contrast, trace GDF-5 and mild BMP-7 staining was seen in zones of RPE fibrous metaplasia in areas not associated with osseous metaplasia. Mild intracytoplasmic TGF beta1 expression was seen in the RPE metaplasia surrounding the bone when compared with adult eyes. Both fetal and adult eyes showed trace to mild GDF-5 and BMP-7 labelling of the non-pigmented ciliary epithelium which was increased in the eyes with osseous metaplasia. In eyes with osseous metaplasia, a significant decrease in GDF-5 and BMP-7 labelling was noted in fetal keratocytes (p = 0.0159 for both antibodies) when compared to adult eyes. Also, a significant decrease in BMP-7 labelling was seen in keratocytes in eyes with osseous metaplasia (p = 0.0162). CONCLUSIONS: The increase in GDF-5, BMP-7, and TGF beta1 immunoreactivity in zones of RPE metaplasia in eyes with osseous metaplasia suggests that these proteins have an important role in intraocular ectopic bone formation.

Characterization of monoclonal antibodies specific for the V beta 3 family of the human T cell receptor generated using soluble TCR beta-chain.

A soluble, recombinant form of the human T cell receptor (TCR) beta-chain containing the V beta 3.1 sequence has been constructed, expressed in Chinese hamster ovary cells, amplified by dihydrofolate reductase selection, and purified in quantities appropriate for the generation of monoclonal antibodies (mAb). The V beta 3 sequence was chosen because of its reported elevated usage in the synovial T cells of rheumatoid arthritis patients but the approach described should be applicable to other known human V beta gene sequences. By this method, two mAb were prepared which reacted with up to 10% of normal, live peripheral blood T cells but with reactivity varying greatly among individual donors. Both mAb specifically bound to a murine T cell line transfected with a human TCR V beta 3.1 and immunoprecipitated a protein of the expected molecular weight for the TCR beta-chain. Both antibodies were mitogenic for T cells and analysis of peripheral blood lymphocyte cultures stimulated with the mAb suggested that both were specific for the V beta 3.1 subfamily and not D beta or J beta. Clones expressing V beta 3, which were derived from mAb-stimulated peripheral blood lymphocytes of a single individual, preferentially (8/13), but not exclusively, utilized the J beta 2.7 gene segment. The V beta 3.1 usage showed no preference for the CD8+ or CD4+ subpopulations of normal peripheral blood T cells.

Melanogenesis by human uveal melanocytes in vitro.

PURPOSE: To study melanogenesis by cultured human uveal melanocytes, and the relationship between melanin production by uveal melanocytes in vitro with the degree of iris pigmentation in vivo. METHODS: Melanin content, melanin production, and tyrosinase activity of cultured uveal melanocytes derived from eyes of various iris color were measured at different stages of cultivation. RESULTS: Cultured uveal melanocytes maintained a constant level of melanin content, expressed tyrosinase activity, and produced measurable amounts of melanin in vitro. Melanosomes in different stages were seen ultrastructurally. Melanin production correlated directly with the degree of iris pigmentation of the eyes from which the uveal melanocytes were isolated. Tyrosinase activity of cultured uveal melanocytes from black versus white donors was significantly different, but, among white donors, there was no correlation with iris pigmentation or with melanin production in vitro. CONCLUSION: Cultured uveal melanocytes can produce melanin in vitro. Cultured uveal melanocytes isolated from eyes of different iris color maintained their inherent capacity for melanogenesis. Therefore, cultured uveal melanocytes are an excellent model system for studying melanogenesis in uveal melanocytes in vitro.

Familial eosinophilia: clinical and laboratory results on a U.S. kindred.

We describe a five-generation kindred with familial eosinophilia (FE; MIM131400), characterized by the occurrence of sustained eosinophilia of unidentifiable cause in multiple relatives. The inheritance pattern is consistent with an autosomal dominant pattern. Among 52 related subjects studied, 19 were affected and 33 were unaffected. Ten unaffected spouses were also evaluated. Four subjects with sustained eosinophilia were diagnosed with cardiac abnormalities and two of them also had neurologic symptoms. In comparison with the unaffected or spouses, evaluation of complete blood counts showed that the affected relatives had, as expected, significantly higher white cell (P < 0.005) and absolute eosinophil counts (P < 0.001) and lower red cell counts (P < 0.05). Evaluation of serum cytokine levels (IL-5, IL-3, and granulocyte-macrophage colony-stimulating factor (GMCSF) and serology for parasitic helminth infection demonstrated no differences between the affected and unaffected individuals; no individuals studied had serologic evidence for parasitic infection. There were also no differences in anti-nuclear antibody, serum cobalamin (vitamin B12) level, immunoglobulin level, leukocyte alkaline phosphatase, rheumatoid factor, HLA analysis, and stool findings for ova and parasites. Among eight affected persons who had peripheral blood or bone marrow karyotype analysis, two carried the same chromosome abnormality, a pericentric inversion of chromosome 10, inv (10) (p11.2q21.2). A gene mapping study is currently underway to study the underlying genetic mechanism(s) of this syndrome.

NADPH-diaphorase histochemistry of rat choroid plexus blood vessels and epithelium.

Choroid plexus is the major source of cerebrospinal fluid. The hemodynamics and secretory function of this tissue are controlled by multiple endocrine and neural mechanisms. Nitric oxide (NO) has been demonstrated to play an important role in regulating choroidal blood flow. In the present study, performed on adult male Sprague-Dawley rats, we employed a NADPH-diaphorase (NADPH-d) histochemical method to localize nitrergic innervation of choroidal blood vessels. This approach was based on previous observations that NADPH-d colocalizes with NO synthase, a synthetic enzyme for NO, in the central and peripheral nervous systems. NADPH-d-positive nerve fibers were found to accompany both large arteries and veins and blood microvessels (possibly arterioles) located in choroidal stroma. NADPH-d reaction product was also localized to the vascular endothelial lining and choroidal epithelial cells. All the above sources of NO may play important roles in the regulation of secretory and hemodynamic functions of the choroid plexus.

Study of crystallization of endogenous surfactant in Eudragit NE30D-free films and its influence on drug-release properties of controlled-release diphenhydramine HCl pellets coated with Eudragit NE30D.

This study investigates the crystallization of the endogenous surfactant nonoxynol 100 in Eudragit NE30D-free films during storage and the influences of nonoxynol 100 on the dissolution of diphenhydramine hydrochloric acid (HCl) pellets coated with Eudragit NE30D before and after aging at ambient conditions. Polarizing light microscopy showed that when Eudragit NE30D-free films were stored at ambient conditions, off-white, flower-shaped crystals formed and increased in the polymer film as storage time increased. Also, x-ray diffraction showed polymer crystals in the aged free film. Thermogravimetric analysis showed no evidence of combined volatile molecules with the polymer molecules, and Fourier transformed infrared spectroscopy (FTIR) data suggested the same chemical composition of the polymer before and after phase separation. Further, from normal light microscopy, the appearance of the melting droplets in the polymer film indicated that the polymer molecules did not form the crystals. After the extraction of nonoxynol 100 by water, the free film formed by the water-extracted Eudragit NE30D was found free of the crystals after aging at the same conditions. The combination of the thermogravimetric analysis, FTIR, and microscopy showed that the origin of the crystals in dry Eudragit NE30D-free films came from nonoxynol 100, and not from the polymer molecules themselves. Monitoring by differential scanning calorimeter, it was found that the rates of crystallization of nonoxynol 100 were faster when the films were stored at 30 degrees C and 40 degrees C than when stored at ambient conditions and 45 degrees C. When stored at -5 degrees C, the crystallization rate was nearly zero. As the temperature got closer to melting temperature, the crystallization rate was very low because the system was in a thermodynamically disfavored state. The rate gradually increased and finally passed through a maximum as the crystallization temperature decreased. As the temperature kept decreasing, the crystallization rate became small again and eventually stopped because the system turned into a kinetically disfavored state. Because the phase transition of nonoxynol 100 in Eudragit NE30D occurred at ambient conditions, its influence on the dissolution of diphenhydramine HCl pellets coated with Eudragit NE30D was studied. Three different levels of nonoxynol 100 were used in Eudragit NE30D dispersions to make 3 different batches of Eudragit NE30D film-coated, controlled-release diphenhydramine HCl pellets. The results showed the dissolution rate increased as the level of nonoxynol 100 increased in the coating formula. Compared to the commonly used water-soluble additive human peripheral mononuclear cell, nonoxynol 100 was more effective in enhancing the dissolution of diphenhydramine HCl from pellets coated with Eudragit NE30D. Further study showed that the phase separation of the surfactant during aging tends to stabilize or slightly increase dissolution rates at higher surfactant levels.

[Effects of calcimycin on platelet adhesion to cultured bovine cerebral microvascular endothelial cells and its antagonism by drugs].

Calcimycin induced rabbit platelet adhesion to cultured bovine cerebral microvascular endothelial cells (CMEC) and its inhibition by triazelodiazepine (WEB 2086), 1,5-bis-(3,4-dimethoxyphenyl)-tetrahydro-(4H)-pyran (DMPP) and tetrandrine (Tet) were investigated. The results showed that calcimycin significantly increased platelet adhesion to CMEC. The platelet adhesion to CMEC was increased by 17.1% vs control after stimulation with calcimycin 0.01 mumol.L-1 for 25 min. WEB 2086 0.1, 1.0 and 10.0 mumol.L-1 or DMPP 0.1, 1.0 and 10.0 mumol.L-1 or Tet 0.1, 1.0 and 10.0 mumol.L-1 inhibited the calcimycin induced platelet adhesion to CMEC by 9.0, 22.9 and 23.1% or 9.7, 15.6 and 22.1% or 7.8, 15.6 and 24.6%, respectively. This indicates that DMPP and Tet may have perspectives in the prevention and treatment of cerebral vascular diseases.